Publications by authors named "Moo-Ho Won"

610 Publications

Comparison of Neuronal Death, Blood-Brain Barrier Leakage and Inflammatory Cytokine Expression in the Hippocampal CA1 Region Following Mild and Severe Transient Forebrain Ischemia in Gerbils.

Neurochem Res 2021 May 29. Epub 2021 May 29.

Department of Biomedical Science, Research Institute of Bioscience and Biotechnology, Hallym University, Chuncheon, Gangwon, 24252, Republic of Korea.

Transient ischemia in the brain causes blood-brain barrier (BBB) breakdown and dysfunction, which is related to ischemia-induced neuronal damage. Leakage of plasma proteins following transient ischemia is one of the indicators that is used to determine the extent of BBB dysfunction. In this study, neuronal damage/death, leakage of albumin and IgG, microgliosis, and inflammatory cytokine expression were examined in the hippocampal CA1 region, which is vulnerable to transient ischemia, following 5-min (mild) and 15-min (severe) ischemia in gerbils induced by transient common carotid arteries occlusion (tCCAo). tCCAo-induced neuronal damage/death occurred earlier and was more severe after 15-min tCCAo vs. after 5-min tCCAo. Significant albumin and IgG leakage (albumin and IgG immunoreactivity) took 1 or 2 days to begin, and immunoreactivity was markedly increased 5 days after 5-min tCCAo. While, albumin and IgG leakage began to increase 6 h after 15-min tCCAo and remained significantly higher over time than that seen in 5-min tCCAo. IgG immunoreactivity was observed in degenerating neurons and activated microglia after tCCAo, and microglia were activated to a greater extent after 15-min tCCAo than 5-min tCCAo. In addition, following 15-min tCCAo, pro-inflammatory cytokines [tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β)] immunoreactivity was significantly higher than that seen following 5-min tCCAo, whereas immunoreactivity of anti-inflammatory cytokines (IL-4 and IL-13) was lower in 15-min than 5-min tCCAo. These results indicate that duration of tCCAo differentially affects the timing and degree of neuronal damage or loss, albumin and IgG leakage and inflammatory cytokine expression in brain tissue. In addition, more severe BBB leakage is closely related to acceleration of neuronal damage through increased microglial activation and pro-inflammatory cytokine expression in the ischemic hippocampal CA1 region.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11064-021-03362-6DOI Listing
May 2021

Effects of hypothermia on inflammatory cytokine expression in rat liver following asphyxial cardiac arrest.

Exp Ther Med 2021 Jun 15;21(6):626. Epub 2021 Apr 15.

Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea.

Hypothermic treatment is known to protect against cardiac arrest (CA) and improve survival rate. However, few studies have evaluated the CA-induced liver damage and the effects of hypothermia on this damage. Therefore, the aim of the present study was to determine possible protective effects of hypothermia on the liver after asphyxial CA. Rats were subjected to a 5-min asphyxial CA followed by return of spontaneous circulation (ROSC). The body temperature was controlled at 37±0.5˚C (normothermia group) or 33±0.5˚C (hypothermia group) for 4 h after ROSC. Livers were examined at 6, 12 h, 1 and 2 days after ROSC. Histopathological examination was performed by H&E staining. Alterations in the expression levels of pro-inflammatory (TNF-α and interleukin IL-2) and anti-inflammatory cytokines (IL-4 and IL-13) were investigated by immunohistochemistry. Sinusoidal dilatation and vacuolization were observed after asphyxial CA by histopathological examination. However, these CA-induced structural alterations were prevented by hypothermia. In immunohistochemical examination, the expression levels of pro-inflammatory cytokines were reduced in the hypothermia group compared with those in the normothermia group while the expression levels of anti-inflammatory cytokines were increased in the hypothermia group compared with those in the normothermia group. In conclusion, hypothermic treatment for 4 h following asphyxial CA in rats inhibited the increase of pro-inflammatory cytokines and stimulated the expression of anti-inflammatory cytokines compared with the normothermic group. The results of the present study suggested that hypothermic treatment after asphyxial CA reduced liver damage via the regulation of inflammation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3892/etm.2021.10058DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8097226PMC
June 2021

Arginase II protein regulates Parkin-dependent p32 degradation that contributes to Ca2+-dependent eNOS activation in endothelial cells.

Cardiovasc Res 2021 May 8. Epub 2021 May 8.

Department of Biological Sciences.

Aims: Arginase II (ArgII) plays a key role in the regulation of Ca2+ between the cytosol and mitochondria in a p32-dependent manner. p32 contributes to endothelial nitric oxide synthase (eNOS) activation through the Ca2+/CaMKII/AMPK/p38MAPK/Akt signaling cascade. Therefore, we investigated a novel function of ArgII in the regulation of p32 stability.

Methods And Results: mRNA levels were measured by qRT-PCR, and protein levels and activation were confirmed by western blot analysis. Ca2+ concentrations were measured by FACS analysis and a vascular tension assay was performed. ArgII bound to p32, and ArgII protein knockdown using siArgII facilitated the ubiquitin-dependent proteasomal degradation of p32. β-lactone, a proteasome inhibitor, inhibited the p32 degradation associated with endothelial dysfunction in a Ca2+-dependent manner. The amino acids Lys154, Lys 180, and Lys220 of the p32 protein were identified as putative ubiquitination sites. When these sites were mutated, p32 was resistant to degradation in the presence of siArgII, and endothelial function was impaired. Knockdown of Pink/Parkin as an E3-ubiquitin ligase with siRNAs resulted in increased p32, decreased [Ca2+]c, and attenuated CaMKII-dependent eNOS activation by siArgII. SiArgII-dependent Parkin activation was attenuated by KN93, a CaMKII inhibitor. Knockdown of ArgII mRNA and its gene, but not inhibition of its activity, accelerated the interaction between p32 and Parkin and reduced p32 levels. In aortas of ArgII-/- mice, p32 levels were reduced by activated Parkin and inhibition of CaMKII attenuated Parkin-dependent p32 lysis. SiParkin blunted the phosphorylation of the activated CaMKII/AMPK/p38MAPK/Akt/eNOS signaling cascade. However, ApoE-/- mice fed a high-cholesterol diet had greater ArgII activity, significantly attenuated phosphorylation of Parkin, and increased p32 levels. Incubation with siArgII augmented p32 ubiquitination through Parkin activation, and induced signaling cascade activation.

Conclusion: The results suggest a novel function for ArgII protein in Parkin-dependent ubiquitination of p32 that is associated with Ca2+-mediated eNOS activation in endothelial cells.

Translational Perspective: In many vascular disorders, the downregulation of ArgII has been shown to be beneficial. This enzyme plays a crucial role in the regulation Ca2+ concentrations in a p32-dependent manner and activates the eNOS activation signaling cascade. In this study, we discovered that ArgII downregulation, inhibition of its activity, and gene knockout/down, induced the activation of Parkin (an E3-ubiquitin ligase) through a CaMKII-dependent mechanism. ArgII protein, as a p32 binding partner, prevented Parkin-dependent p32 ubiquitination, but inhibition of ArgII activity had no effect on ubiquitination. These novel findings have the potential to be translated into future therapeutic strategies to treat vascular diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/cvr/cvab163DOI Listing
May 2021

Neuroprotective Effects of Salicin in a Gerbil Model of Transient Forebrain Ischemia by Attenuating Oxidative Stress and Activating PI3K/Akt/GSK3β Pathway.

Antioxidants (Basel) 2021 Apr 20;10(4). Epub 2021 Apr 20.

Department of Biomedical Science, Research Institute for Bioscience and Biotechnology, Hallym University, Chuncheon 24252, Gangwon, Korea.

Salicin is a major natural compound of willow bark and displays diverse beneficial biological properties, such as antioxidant activity. However, little information available for the neuroprotective potential of salicin against ischemic brain injury has been reported. Thus, this study was performed to investigate the neuroprotective potential of salicin against ischemia and reperfusion (IR) injury and its mechanisms in the hippocampus using a gerbil model of 5-min transient ischemia (TI) in the forebrain, in which a massive loss (death) of pyramidal neurons cells occurred in the subfield Cornu Ammonis 1 (CA1) among the hippocampal subregions (CA1-3) at 5 days after TI. To examine neuroprotection by salicin, gerbils were pretreated with salicin alone or together with LY294002, which is a phosphatidylinositol 3-kinase (PI3K) inhibitor, once daily for 3 days before TI. Treatment with 20 mg/kg of salicin significantly protected CA1 pyramidal neurons against the ischemic injury. Treatment with 20 mg/kg of salicin significantly reduced the TI-induced increase in superoxide anion generation and lipid peroxidation in the CA1 pyramidal neurons after TI. The treatment also reinstated the TI-induced decrease in superoxide dismutases (SOD1 and SOD2), catalase, and glutathione peroxidase in the CA1 pyramidal cells after TI. Moreover, salicin treatment significantly elevated the levels of phosphorylation of Akt and glycogen synthase kinase-3β (GSK3β), which is a major downstream target of PI3K, in the ischemic CA1. Notably, the neuroprotective effect of salicin was abolished by LY294002. Taken together, these findings clearly indicate that salicin protects against ischemic brain injury by attenuating oxidative stress and activating the PI3K/Akt/GSK3β pathway.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/antiox10040629DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8074613PMC
April 2021

Ischemia-Reperfusion under Hyperthermia Increases Heme Oxygenase-1 in Pyramidal Neurons and Astrocytes with Accelerating Neuronal Loss in Gerbil Hippocampus.

Int J Mol Sci 2021 Apr 12;22(8). Epub 2021 Apr 12.

Department of Biomedical Science and Research Institute for Bioscience and Biotechnology, Hallym University, Chuncheon 24252, Gangwon, Korea.

It has been studied that the damage or death of neurons in the hippocampus is different according to hippocampal subregions, cornu ammonis 1-3 (CA1-3), after transient ischemia in the forebrain, showing that pyramidal neurons located in the subfield CA1 (CA1) are most vulnerable to this ischemia. Hyperthermia is a proven risk factor for brain ischemia and can develop more severe and extensive brain damage related with mortality rate. It is well known that heme oxygenase-1 (HO-1) activity and expression is increased by various stimuli in the brain, including hyperthermia. HO-1 can be either protective or deleterious in the central nervous system, and its roles depend on the expression levels of enzymes. In this study, we investigated the effects of hyperthermia during ischemia on HO-1 expression and neuronal damage/death in the hippocampus to examine the relationship between HO-1 and neuronal damage/death following 5-min transient ischemia in the forebrain using gerbils. Gerbils were assigned to four groups: (1) sham-operated gerbils with normothermia (Normo + sham group); (2) ischemia-operated gerbils with normothermia (Normo + ischemia group); (3) sham-operated gerbils with hyperthermia (39.5 ± 0.2 °C) during ischemia (Hyper + sham group); and (4) ischemia-operated gerbils with hyperthermia during ischemia (Hyper + ischemia group). HO-1 expression levels in CA1-3 of the Hyper + ischemia group were significantly higher than those in the Normo + ischemia group. HO-1 immunoreactivity in the Hyper + ischemia group was significantly increased in pyramidal neurons and astrocytes with time after ischemia, and the immunoreactivity was significantly higher than that in the Normo + ischemia group. In the Normo + Ischemia group, neuronal death was shown in pyramidal neurons located only in CA1 at 5 days after ischemia. However, in the Hyper + ischemia group, pyramidal neuronal death occurred in CA1-3 at 2 days after ischemia. Taken together, our findings showed that brain ischemic insult during hyperthermic condition brings up earlier and severer neuronal damage/death in the hippocampus, showing that HO-1 expression in neurons and astrocytes is different according to brain subregions and temperature condition. Based on these findings, we suggest that hyperthermia in patients with ischemic stroke must be taken into the consideration in the therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms22083963DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8068892PMC
April 2021

Therapeutic Effects of Decursin and Nakai Root Extract in Gerbil Brain after Transient Ischemia via Protecting BBB Leakage and Astrocyte Endfeet Damage.

Molecules 2021 Apr 9;26(8). Epub 2021 Apr 9.

Department of Biomedical Science and Research Institute for Bioscience and Biotechnology, Hallym University, Chuncheon 24252, Korea.

Nakai root contains decursin which exerts beneficial properties such as anti-amnesic and anti-inflammatory activities. Until now, however, the neuroprotective effects of decursin against transient ischemic injury in the forebrain have been insufficiently investigated. Here, we revealed that post-treatment with decursin and the root extract saved pyramidal neurons in the hippocampus following transient ischemia for 5 min in gerbil forebrain. Through high-performance liquid chromatography, we defined that decursin was contained in the extract as 7.3 ± 0.2%. Based on this, we post-treated with 350 mg/kg of extract, which is the corresponding dosage of 25 mg/kg of decursin that exerted neuroprotection in gerbil hippocampus against the ischemia. In addition, behavioral tests were conducted to evaluate ischemia-induced dysfunctions via tests of spatial memory (by the 8-arm radial maze test) and learning memory (by the passive avoidance test), and post-treatment with the extract and decursin attenuated ischemia-induced memory impairments. Furthermore, we carried out histochemistry, immunohistochemistry, and double immunohistofluorescence. Pyramidal neurons located in the subfield cornu ammonis 1 (CA1) among the hippocampal subfields were dead at 5 days after the ischemia; however, treatment with the extract and decursin saved the pyramidal neurons after ischemia. Immunoglobulin G (IgG, an indicator of extravasation), which is not found in the parenchyma in normal brain tissue, was apparently shown in CA1 parenchyma from 2 days after the ischemia, but IgG leakage was dramatically attenuated in the CA1 parenchyma treated with the extract and decursin. Furthermore, astrocyte endfeet, which are a component of the blood-brain barrier (BBB), were severely damaged at 5 days after the ischemia; however, post-treatment with the extract and decursin dramatically attenuated the damage of the endfeet. In brief, therapeutic treatment of the extract of Nakai root and decursin after 5 min transient forebrain ischemia protected hippocampal neurons from the ischemia, showing that ischemia-induced BBB leakage and damage of astrocyte endfeet was significantly attenuated by the extract and decursin. Based on these findings, we suggest that Nakai root containing decursin can be employed as a pharmaceutical composition to develop a therapeutic strategy for brain ischemic injury.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules26082161DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8069195PMC
April 2021

Korean Red ginseng prevents endothelial senescence by downregulating the HO-1/NF-κB/miRNA-155-5p/eNOS pathway.

J Ginseng Res 2021 Mar 14;45(2):344-353. Epub 2020 Aug 14.

Department of Molecular and Cellular Biochemistry, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do 24341, South Korea.

Background: Korean Red ginseng extract (KRGE) has beneficial effects on the cardiovascular system by improving endothelial cell function. However, its pharmacological effect on endothelial cell senescence has not been clearly elucidated. Therefore, we examined the effect and molecular mechanism of KRGE on the senescence of human umbilical vein endothelial cells (HUVECs).

Methods: HUVECs were grown in normal or KRGE-supplemented medium. Furthermore, they were transfected with heme oxygenase-1 (HO-1) gene or treated with its inhibitor, a NF-B inhibitor, and a miR-155-5p mimic or inhibitor. Senescence-associated characteristics of endothelial cells were determined by biochemical and immunohistochemical analyses.

Results: Treatment of HUVECs with KRGE resulted in delayed onset and progression of senescence-associated characteristics, such as increased lysosomal acidic β-galactosidase and decreased telomerase activity, angiogenic dysfunction, and abnormal cell morphology. KRGE preserved the levels of anti-senescent factors, such as eNOS-derived NO, MnSOD, and cyclins D and A: however, it decreased the levels of senescence-promoting factors, such as ROS, activated NF-B, endothelial cell inflammation, and p21 expression. The beneficial effects of KRGE were due to the induction of HO-1 and the inhibition of NF-B-dependent biogenesis of miR-155-5p that led to the downregulation of eNOS. Moreover, treatment with inhibitors of HO-1, NF-B, and miR-155-5p abolished the anti-senescence effects of KRGE.

Conclusion: KRGE delayed or prevented HUVEC senescence through a signaling cascade involving the induction of HO-1, the inhibition of NF-B-dependent miR-155-5p biogenesis, and the maintenance of the eNOS/NO axis activity, suggesting that it may protect against vascular diseases associated with endothelial senescence.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jgr.2020.08.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8020293PMC
March 2021

Comparison of age-dependent alterations in thioredoxin 2 and thioredoxin reductase 2 expressions in hippocampi between mice and rats.

Lab Anim Res 2021 Mar 6;37(1):11. Epub 2021 Mar 6.

Department of Biomedical Science and Research Institute for Bioscience and Biotechnology, Hallym University, 24252, Chuncheon, Gangwon, Republic of Korea.

Background: Aging is one of major causes triggering neurophysiological changes in many brain substructures, including the hippocampus, which has a major role in learning and memory. Thioredoxin (Trx) is a class of small redox proteins. Among the Trx family, Trx2 plays an important role in the regulation of mitochondrial membrane potential and is controlled by TrxR2. Hitherto, age-dependent alterations in Trx2 and TrxR2 in aged hippocampi have been poorly investigated. Therefore, the aim of this study was to examine changes in Trx2 and TrxR2 in mouse and rat hippocampi by age and to compare their differences between mice and rats.

Results: Trx2 and TrxR2 levels using Western blots in mice were the highest at young age and gradually reduced with time, showing that no significant differences in the levels were found between the two subfields. In rats, however, their expression levels were the lowest at young age and gradually increased with time. Nevertheless, there were no differences in cellular distribution and morphology in their hippocampi when it was observed by cresyl violet staining. In addition, both Trx2 and TrxR2 immunoreactivities in the CA1-3 fields were mainly shown in pyramidal cells (principal cells), showing that their immunoreactivities were altered like changes in their protein levels.

Conclusions: Our current findings suggest that Trx2 and TrxR2 expressions in the brain may be different according to brain regions, age and species. Therefore, further studies are needed to examine the reasons of the differences of Trx2 and TrxR2 expressions in the hippocampus between mice and rats.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s42826-021-00088-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7937215PMC
March 2021

Transient forebrain ischemia under hyperthermic condition accelerates memory impairment and neuronal death in the gerbil hippocampus by increasing NMDAR1 expression.

Mol Med Rep 2021 04 4;23(4). Epub 2021 Feb 4.

Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea.

Altered expression levels of N‑methyl‑D‑aspartate receptor (NMDAR), a ligand‑gated ion channel, have a harmful effect on cellular survival. Hyperthermia is a proven risk factor of transient forebrain ischemia (tFI) and can cause extensive and severe brain damage associated with mortality. The objective of the present study was to investigate whether hyperthermic preconditioning affected NMDAR1 immunoreactivity associated with deterioration of neuronal function in the gerbil hippocampal CA1 region following tFI via histological and western blot analyses. Hyperthermic preconditioning was performed for 1 h before tFI, which was developed by ligating common carotid arteries for 5 min. tFI‑induced cognitive impairment under hyperthermia was worse compared with that under normothermia. Loss (death) of pyramidal neurons in the CA1 region occurred fast and was more severe under hyperthermia compared with that under normothermia. NMDAR1 immunoreactivity was not observed in the somata of pyramidal neurons of sham gerbils with normothermia. However, its immunoreactivity was strong in the somata and processes at 12 h post‑tFI. Thereafter, NMDAR1 immunoreactivity decreased with time after tFI. On the other hand, NMDAR1 immunoreactivity under hyperthermia was significantly increased in the somata and processes at 6 h post‑tFI. The change pattern of NMDAR1 immunoreactivity under hyperthermia was different from that under normothermia. Overall, accelerated tFI‑induced neuronal death under hyperthermia may be closely associated with altered NMDAR1 expression compared with that under normothermia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3892/mmr.2021.11895DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7893780PMC
April 2021

CD200 Change Is Involved in Neuronal Death in Gerbil Hippocampal CA1 Field Following Transient Forebrain Ischemia and Postischemic Treatment with Risperidone Displays Neuroprotection without CD200 Change.

Int J Mol Sci 2021 Jan 23;22(3). Epub 2021 Jan 23.

Department of Pharmacy, College of Pharmacy, Dankook University, Cheonan 31116, Chungnam, Korea.

It has been reported that CD200 (Cluster of Differentiation 200), expressed in neurons, regulates microglial activation in the central nervous system, and a decrease in CD200 expression causes an increase in microglial activation and neuronal loss. The aim of this study was to investigate time-dependent changes in CD200 expression in the hippocampus proper (CA1, 2, and 3 fields) after transient forebrain ischemia for 5 min in gerbils. In this study, 5-min ischemia evoked neuronal death (loss) of pyramidal neurons in the CA1 field, but not in the CA2/3 fields, at 5 days postischemia. In the sham group, CD200 expression was found in pyramidal neurons of the CA1 field, and the immunoreactivity in the group with ischemia was decreased at 6 h postischemia, dramatically increased at 12 h postischemia, decreased (to level found at 6 h postischemia) at 1 and 2 days postischemia, and significantly increased again at 5 days postischemia. At 5 days postischemia, CD200 immunoreactivity was strongly expressed in microglia and GABAergic neurons. However, in the CA3 field, the change in CD200 immunoreactivity in pyramidal neurons was markedly weaker than that in the CA1 field, showing there was no expression of CD 200 in microglia and GABAergic neurons. In addition, treatment of 10 mg/kg risperidone (an atypical antipsychotic drug) after the ischemia hardly changed CD200 immunoreactivity in the CA1 field, showing that CA1 pyramidal neurons were protected from the ischemic injury. These results indicate that the transient ischemia-induced change in CD200 expression may be associated with specific and selective neuronal death in the hippocampal CA1 field following transient forebrain ischemia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms22031116DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7865463PMC
January 2021

Experimental pretreatment with YES-10, a plant extract rich in scutellarin and chlorogenic acid, protects hippocampal neurons from ischemia/reperfusion injury via antioxidant role.

Exp Ther Med 2021 Mar 7;21(3):183. Epub 2021 Jan 7.

Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea.

(L.) PERS (EALP) and RUPR. (CMR) have been used in traditional remedies due to their medicinal effects. Recently, we reported that pretreatment with 200 mg/kg of YES-10 (a combination of extracts from leaves of EALP and CMR) displayed neuroprotective effects against brain ischemia and reperfusion injury. The present study analyzed the major ingredients of YES-10 and investigated whether neuroprotection from YES-10 was dependent upon antioxidant effects in the cornu ammonis 1 (CA1) field in the gerbil hippocampus, after transient forebrain ischemia for 5 min. YES-10 was demonstrated to predominantly contain scutellarin and chlorogenic acid. Pretreatment with YES-10 significantly increased protein levels and the immunoreactivity of copper/zinc-superoxide dismutase (SOD1) and manganese-superoxide dismutase (SOD2) was in the pyramidal neurons of the hippocampal CA1 field when these were examined prior to transient ischemia induction. The increased SODs in CA1 pyramidal neurons following YES-10 treatment were maintained after ischemic injury. In this case, the CA1 pyramidal neurons were protected from ischemia-reperfusion injury. Oxidative stress was significantly attenuated in the CA1 pyramidal neurons, and this was determined by 4-hydroxy-2-nonenal immunohistochemistry and dihydroethidium histofluorescence staining. Taken together, the results indicated that YES-10 significantly attenuated transient ischemia-induced oxidative stress and may be utilized for developing a protective agent against ischemic insults.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3892/etm.2021.9614DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7812581PMC
March 2021

Increased Calbindin D28k Expression via Long-Term Alternate-Day Fasting Does Not Protect against Ischemia-Reperfusion Injury: A Focus on Delayed Neuronal Death, Gliosis and Immunoglobulin G Leakage.

Int J Mol Sci 2021 Jan 11;22(2). Epub 2021 Jan 11.

Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Korea.

Calbindin-D28k (CB), a calcium-binding protein, mediates diverse neuronal functions. In this study, adult gerbils were fed a normal diet (ND) or exposed to intermittent fasting (IF) for three months, and were randomly assigned to sham or ischemia operated groups. Ischemic injury was induced by transient forebrain ischemia for 5 min. Short-term memory was examined via passive avoidance test. CB expression was investigated in the Cornu Ammonis 1 (CA1) region of the hippocampus via western blot analysis and immunohistochemistry. Finally, histological analysis was used to assess neuroprotection and gliosis (microgliosis and astrogliosis) in the CA1 region. Short-term memory did not vary significantly between ischemic gerbils with IF and those exposed to ND. CB expression was increased significantly in the CA1 pyramidal neurons of ischemic gerbils with IF compared with that of gerbils fed ND. However, the CB expression was significantly decreased in ischemic gerbils with IF, similarly to that of ischemic gerbils exposed to ND. The CA1 pyramidal neurons were not protected from ischemic injury in both groups, and gliosis (astrogliosis and microgliosis) was gradually increased with time after ischemia. In addition, immunoglobulin G was leaked into the CA1 parenchyma from blood vessels and gradually increased with time after ischemic insult in both groups. Taken together, our study suggests that IF for three months increases CB expression in hippocampal CA1 pyramidal neurons; however, the CA1 pyramidal neurons are not protected from transient forebrain ischemia. This failure in neuroprotection may be attributed to disruption of the blood-brain barrier, which triggers gliosis after ischemic insults.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms22020644DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7827208PMC
January 2021

Therapeutic hypothermia reduces inflammation and oxidative stress in the liver after asphyxial cardiac arrest in rats.

Acute Crit Care 2020 Nov 30;35(4):286-295. Epub 2020 Nov 30.

Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Korea.

Background: Few studies have evaluated the effects of hypothermia on cardiac arrest (CA)-induced liver damage. This study aimed to investigate the effects of hypothermic therapy on the liver in a rat model of asphyxial cardiac arrest (ACA).

Methods: Rats were subjected to 5-minute ACA followed by return of spontaneous circulation (RoSC). Body temperature was controlled at 33°C±0.5°C or 37°C±0.5°C for 4 hours after RoSC in the hypothermia group and normothermia group, respectively. Liver tissues in each group were collected at 6 hours, 12 hours, 1 day, and 2 days after RoSC. To examine hepatic inflammation, mast cells were stained with toluidine blue. Superoxide anion radical production was evaluated using dihydroethidium fluorescence straining and expression of endogenous antioxidants (superoxide dismutase 1 [SOD1] and SOD2) was examined using immunohistochemistry.

Results: There were significantly more mast cells in the livers of the normothermia group with ACA than in the hypothermia group with ACA. Gradual increase in superoxide anion radical production was found with time in the normothermia group with ACA, but production was significantly suppressed in the hypothermia group with ACA relative to the normothermia group with ACA. SOD1 and SOD2 levels were higher in the hypothermia group with ACA than in the normothermia group with ACA.

Conclusions: Experimental hypothermic treatment after ACA significantly inhibited inflammation and superoxide anion radical production in the rat liver, indicating that this treatment enhanced or maintained expression of antioxidants. Our findings suggest that hypothermic therapy after CA can reduce mast cell-mediated inflammation through regulation of oxidative stress and the expression of antioxidants in the liver.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4266/acc.2020.00304DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7808856PMC
November 2020

Neuronal Death in the CNS Autonomic Control Center Comes Very Early after Cardiac Arrest and Is Not Significantly Attenuated by Prompt Hypothermic Treatment in Rats.

Cells 2021 Jan 2;10(1). Epub 2021 Jan 2.

Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon 24341, Korea.

Autonomic dysfunction in the central nervous system (CNS) can cause death after recovery from a cardiac arrest (CA). However, few studies on histopathological changes in animal models of CA have been reported. In this study, we investigated the prevalence of neuronal death and damage in various brain regions and the spinal cord at early times after asphyxial CA and we studied the relationship between the mortality rate and neuronal damage following hypothermic treatment after CA. Rats were subjected to 7-8 min of asphyxial CA, followed by resuscitation and prompt hypothermic treatment. Eight regions related to autonomic control (the cingulate cortex, hippocampus, thalamus, hypothalamus, myelencephalon, and spinal cord) were examined using cresyl violet (a marker for Nissl substance) and Fluoro-Jade B (a marker for neuronal death). The survival rate was 44.5% 1 day post-CA, 18.2% 2 days post-CA and 0% 5 days post-CA. Neuronal death started 12 h post-CA in the gigantocellular reticular nucleus and caudoventrolateral reticular nucleus in the myelencephalon and lamina VII in the cervical, thoracic, lumbar, and sacral spinal cord, of which neurons are related to autonomic lower motor neurons. In these regions, Iba-1 immunoreactivity indicating microglial activation (microgliosis) was gradually increased with time after CA. Prompt hypothermic treatment increased the survival rate at 5 days after CA with an attenuation of neuronal damages and death in the damaged regions. However, the survival rate was 0% at 12 days after CA. Taken together, our study suggests that the early damage and death of neurons related to autonomic lower motor neurons was significantly related to the high mortality rate after CA and that prompt hypothermic therapy could increase the survival rate temporarily after CA, but could not ultimately save the animal.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/cells10010060DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7824613PMC
January 2021

Chemical Composition of a Novel Distillate from Fermented Mixture of Nine Anti-Inflammatory Herbs and Its UVB-Protective Efficacy in Mouse Dorsal Skin via Attenuating Collagen Disruption and Inflammation.

Molecules 2020 Dec 29;26(1). Epub 2020 Dec 29.

Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Korea.

Since ancient times, various herbs have been used in Asia, including Korea, China, and Japan, for wound healing and antiaging of the skin. In this study, we manufactured and chemically analyzed a novel distillate obtained from a fermented mixture of nine anti-inflammatory herbs (, , , , , , ., , and ). The fermentation of natural plants possesses beneficial effects in living systems. These activities are attributed to the chemical conversion of the parent plants to functional constituents which show more potent biological activities. In our current study, the distillate has been manufactured after fermenting the nine oriental medical plants with , followed by distilling. We analyzed the chemical ingredients involved in the distillate and evaluated the effects of topical application of the distillate on ultraviolet B (UVB)-induced skin damage in Institute of Cancer Research (ICR) mice. Topical application of the distillate significantly ameliorated the macroscopic and microscopic morphology of the dorsal skin against photodamage induced by UVB radiation. Additionally, our current results showed that topical application of the distillate alleviated collagen disruption and reduced levels of proinflammatory cytokines (tumor necrosis factor alpha and interleukin 1 β expressions) in the dorsal skin against UVB radiation. Taken together, our current findings suggest that the distillate has a potential to be used as a material to develop a photoprotective adjuvant.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules26010124DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7795019PMC
December 2020

Topical Application of Extract Rich in Chlorogenic Acid and Rutin Reduces UVB-Induced Skin Damage via Attenuating Collagen Disruption in Mice.

Molecules 2020 Oct 7;25(19). Epub 2020 Oct 7.

Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Korea.

, a black chokeberry, contains high levels of phenolic acids and polyphenolic flavonoids and displays antioxidative and anti-inflammatory effects. Through high-performance liquid chromatography for extracts from , we discovered that the extract contained chlorogenic acid and rutin as major ingredients. In this study, we examined the protective effects of the extract against ultraviolet B- (UVB)-induced photodamage in the dorsal skin of institute of cancer research (ICR) mice. Their dorsal skin was exposed to UVB, thereafter; the extract was topically applied once a day for seven days. Photoprotective properties of the extract in the dorsal skin were investigated by clinical skin severity score for skin injury, hematoxylin and eosin staining for histopathology, Masson's trichrome staining for collagens. In addition, we examined change in collagen type I and III, and matrix metalloproteinase (MMP)-1 and MMP-3 by immunohistochemistry. In the UVB-exposed mice treated with the extract, UVB-induced epidermal damage was significantly ameliorated, showing that epidermal thickness was moderated. In these mice, immunoreactivities of collagen type I and III were significantly increased, whereas immunoreactivities of MMP-1 and 3 were significantly decreased compared with those in the UVB-exposed mice. These results indicate that treatment with extract attenuates UV-induced photodamage by attenuating UVB-induced collagen disruption: these findings might be a result of the chlorogenic acid and rutin contained in the extract. Based on the current results, we suggest that can be a useful material for developing photoprotective adjuvant.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules25194577DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7582310PMC
October 2020

Circulating miRNAs Associated with Dysregulated Vascular and Trophoblast Function as Target-Based Diagnostic Biomarkers for Preeclampsia.

Cells 2020 08 31;9(9). Epub 2020 Aug 31.

Departments of Molecular and Cellular Biochemistry, School of Medicine, Kangwon National University, Chuncheon, Gangwon-do 24341, Korea.

Preeclampsia (PE) is a pregnancy-specific disorder associated with hypertension and proteinuria. Since there is no proven method to treat PE, early prediction and accurate diagnosis are essential for appropriate management of the disease. Thus, reliable biomarkers for diagnosing PE need to be identified and evaluated. We analyzed serum-soluble factors and miRNAs in 92 patients with PE and an equal number of healthy controls to identify new useful biomarkers for PE. Serum miR-31-5p, miR-155-5p, and miR-214-3p levels were significantly elevated in these patients and highly correlated with clinical symptoms of hypertension and proteinuria, whereas the miR-1290-3p level was decreased. The increased miRNAs were upregulated in an NF-κB-dependent manner and suppressed endothelial nitric oxide synthase (eNOS) and placental growth factor (PlGF) expression. The level of each miRNA had greater than 90% diagnostic accuracy, which was further increased by analyzing its ratio relative to that of miR-1290-3p. Taken together, the ratios of miR-31-5p, miR-155-5p, or miR-214-3p to miR-1290-3p may serve as reliable diagnostic or prognostic tools for PE, thereby providing evidence that these miRNAs are promising mechanism-based targets for designing therapeutic and preventive strategies for the clinical management of PE.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/cells9092003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7565195PMC
August 2020

High fat diet accelerates and exacerbates microgliosis and neuronal damage/death in the somatosensory cortex after transient forebrain ischemia in gerbils.

Lab Anim Res 2020 20;36:28. Epub 2020 Aug 20.

Department of Emergency Medicine, and Institute of Medical Sciences, Kangwon National University Hospital, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341 Republic of Korea.

Obesity has been known as an independent risk factor for stroke. Effects of high-fat diet (HFD)-induced obesity on neuronal damage in the somatosensory cortex of animal models of cerebral ischemia have not been studied yet. In this study, HFD-induced obesity was used to study the impact of obesity on neuronal damage/loss and microgliosis in the somatosensory cortex of a gerbil model of 5-min transient forebrain ischemia. We used gerbils fed normal diet (ND) and HFD and chronologically examined microgliosis (microglial cell activation) by ionized calcium-binding adapter molecule 1 (Iba-1) immunohistochemistry. In addition, we examined neuronal damage or death by using neuronal nuclear protein (NeuN, a neuronal marker) immunohistochemistry and Fluoro-Jade B (F-J B, a marker for neuronal degeneration) histofluorescence staining. We found that ischemia-induced microgliosis in ND-fed gerbils was increased from 2 days post-ischemia; however, ischemia-mediated microgliosis in HFD-fed gerbils increased from 1 day post-ischemia and more accelerated with time than that in the ND-fed gerbils. Ischemia-induced neuronal death/loss in the somatosensory cortex in the ND-fed gerbils was apparently found at 5 days post-ischemia. However, in the HFD-fed gerbils, neuronal death/loss was shown from 2 days post-ischemia and progressively exacerbated at 5 days post-ischemia. Our findings indicate that HFD can evoke earlier microgliosis and more detrimental neuronal death/loss in the somatosensory cortex after transient ischemia than ND evokes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s42826-020-00061-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7439675PMC
August 2020

Pycnogenol Supplementation Attenuates Memory Deficits and Protects Hippocampal CA1 Pyramidal Neurons via Antioxidative Role in a Gerbil Model of Transient Forebrain Ischemia.

Nutrients 2020 Aug 17;12(8). Epub 2020 Aug 17.

Department of Anatomy, College of Korean Medicine, Dongguk University, Gyeongju, Gyeongbuk 38066, Korea.

Pycnogenol (an extract of the bark of French maritime pine tree) is used for dietary supplement and known to have excellent antioxidative efficacy. However, there are few reports on neuroprotective effect of Pycnogenol supplementation and its mechanisms against ischemic injury following transient forebrain ischemia (TFI) in gerbils. Now, we examined neuroprotective effect and its mechanisms of Pycnogenol in the gerbils with 5-min TFI, which evokes a significant death (loss) of pyramidal cells located in the cornu ammonis (CA1) region of gerbil hippocampus from 4-5 days post-TFI. Gerbils were pretreated with 30, 40, and 50 mg/kg of Pycnogenol once a day for 7 days before TFI surgery. Treatment with 50 mg/kg, not 30 or 40 mg/kg, of Pycnogenol potently protected learning and memory, as well as CA1 pyramidal cells, from ischemic injury. Treatment with 50 mg/kg Pycnogenol significantly enhanced immunoreactivity of antioxidant enzymes (superoxide dismutases and catalase) in the pyramidal cells before and after TFI induction. Furthermore, the treatment significantly reduced the generation of superoxide anion, ribonucleic acid oxidation and lipid peroxidation in the pyramidal cells. Moreover, interestingly, its neuroprotective effect was abolished by administration of sodium azide (a potent inhibitor of SODs and catalase activities). Taken together, current results clearly indicate that Pycnogenol supplementation can prevent neurons from ischemic stroke through its potent antioxidative role.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/nu12082477DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7468866PMC
August 2020

Effects of Decursin and Nakai Root Extract on Hair Growth in Mouse Dorsal Skin via Regulating Inflammatory Cytokines.

Molecules 2020 Aug 13;25(16). Epub 2020 Aug 13.

Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Korea.

This current study investigates the facilitative effects and mechanisms of decursin, a major component of Nakai (AGN), and AGN root extract on hair growth in mice. We perform high-performance liquid chromatography on AGN extract to show it contains 7.3% decursin. Hairs in mouse dorsal skin are shaved distilled in water, 0.15% decursin, and 2% AGN root extract (0.15% decursin in the diluted extract) and topically applied twice a day for 17 days. Hematoxylin and eosin staining are done to examine the morphological changes in the hair follicles. To compare the effects of decursin and AGN extract on inflammatory cytokines in the dorsal skin, Western blot analysis and immunohistochemistry for tumor necrosis factor α (TNF-α) and interleukin (IL)-1β as pro-inflammatory cytokines, and IL-4 and IL-13 as anti-inflammatory cytokines are conducted. The results show that the application of decursin and AGN extract confer effects on hair growth. Hair growth is significantly facilitated from seven days after the treatments compared to that in the control group, and completely grown hair was found 17 days after the treatments. The protein levels and immunoreactivity of TNF-α and IL-1β in this case are significantly decreased, whereas the IL-4 and IL-13 levels and immunoreactivity are significantly increased compared to those in the control group. Additionally, high-mobility group box 1, an inflammatory mediator, is elevated by the topical application of decursin and AGN extract. Taken together, the treatment of mouse dorsal skin with AGE root extract containing decursin promotes hair growth by regulating pro- and/or anti-inflammatory cytokines. We, therefore, suggest that AGN root extract as well as decursin can be utilized as materials for developing hair growth-facilitating treatments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules25163697DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7464339PMC
August 2020

Experimental Pretreatment with Chlorogenic Acid Prevents Transient Ischemia-Induced Cognitive Decline and Neuronal Damage in the Hippocampus through Anti-Oxidative and Anti-Inflammatory Effects.

Molecules 2020 Aug 6;25(16). Epub 2020 Aug 6.

Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Korea.

Chlorogenic acid (CGA), an ester of caffeic acid and quinic acid, is among the phenolic acid compounds which can be naturally found in green coffee extract and tea. CGA has been studied since it displays significant pharmacological properties. The aim of this study was to investigate the effects of CGA on cognitive function and neuroprotection including its mechanisms in the hippocampus following transient forebrain ischemia in gerbils. Memory and learning following the ischemia was investigated by eight-arm radial maze and passive avoidance tests. Neuroprotection was examined by immunohistochemistry for neuronal nuclei-specific protein and Fluoro-Jade B histofluorescence staining. For mechanisms of the neuroprotection, alterations in copper, zinc-superoxide dismutase (SOD1), SOD2 as antioxidant enzymes, dihydroethidium and 4-hydroxy-2-nonenal as indicators for oxidative stress, and anti-inflammatory cytokines (interleukin (IL)-4 and IL-13) and pro-inflammatory cytokines (tumor necrosis factor α (TNF-α) and IL-2) were examined by Western blotting and/or immunohistochemistry. As a result, pretreatment with 30 mg/kg CGA attenuated cognitive impairment and displayed a neuroprotective effect against transient forebrain ischemia (TFI). In Western blotting, the expression levels of SOD2 and IL-4 were increased due to pretreatment with CGA and, furthermore, 4-HNE production and IL-4 expressions were inhibited by CGA pretreatment. Additionally, pretreated CGA enhanced antioxidant enzymes and anti-inflammatory cytokines and, in contrast, attenuated oxidative stress and pro-inflammatory cytokine expression. Based on these results, we suggest that CGA can be a useful neuroprotective material against ischemia-reperfusion injury due to its antioxidant and anti-inflammatory efficacies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules25163578DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7463954PMC
August 2020

NF-κB-dependent miR-31/155 biogenesis is essential for TNF-α-induced impairment of endothelial progenitor cell function.

Exp Mol Med 2020 08 7;52(8):1298-1309. Epub 2020 Aug 7.

Department of Molecular and Cellular Biochemistry, Kangwon National University School of Medicine, Chuncheon, Gangwon-do, 24341, South Korea.

Endothelial progenitor cell (EPC) dysfunction impairs vascular function and remodeling in inflammation-associated diseases, including preeclampsia. However, the underlying mechanism of this inflammation-induced dysfunction remains unclear. In the present study, we found increases in TNF-α and miR-31/155 levels and reduced numbers of circulating EPCs in patients with preeclampsia. Patient-derived mononuclear cells (MNCs) cultured in autologous serum had decreased endothelial nitric oxide synthase (eNOS) expression, nitric oxide production, and differentiation into EPCs with angiogenic potential, and these effects were inhibited by a TNF-α-neutralizing antibody and miR-31/155 inhibitors. Moreover, TNF-α treatment of normal MNCs increased miR-31/155 biogenesis, decreased eNOS expression, reduced EPC differentiation, and impaired angiogenic potential. The TNF-α-induced impairment of EPC differentiation and function was rescued by NF-κB p65 knockdown or miR-31/155 inhibitors. In addition, treatment of MNCs with synthetic miR-31/155 or an eNOS inhibitor mimicked the inhibitory effects of TNF-α on eNOS expression and EPC functions. Moreover, transplantation of EPCs that had been differentiated from TNF-α-treated MNCs decreased neovascularization and blood perfusion in ischemic mouse hindlimbs compared with those of normally differentiated EPCs. These findings suggest that NF-κB activation is required for TNF-α-induced impairment of EPC mobilization, differentiation, and function via miR-31/155 biogenesis and eNOS downregulation. Our data provide a new role for NF-κB-dependent miR-31/155 in EPC dysfunction under the pathogenic conditions of inflammation-associated vascular diseases, including preeclampsia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s12276-020-0478-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8080610PMC
August 2020

Brain Factor-7® improves learning and memory deficits and attenuates ischemic brain damage by reduction of ROS generation in stroke in vivo and in vitro.

Lab Anim Res 2020 29;36:24. Epub 2020 Jul 29.

Department of Neurobiology, School of Medicine, Kangwon National University, 1 Kangwondaehak-gil, Chuncheon, Gangwon 24341 Republic of Korea.

Brain Factor-7® (BF-7), silk fibroin peptide, is known to be effective in improvement of memory and learning ability. In this study, the effects of BF-7 (10 mg/kg, p.o., pre-treatment for 7 days and post-treatment for 7 days) on neuroprotection and memory and learning functions were investigated in a rat model of transient focal cerebral ischemia and a gerbil model of transient global forebrain ischemia. Furthermore, to find the mechanism of BF-7, we examined the neuroprotective and antioxidative effects of BF-7 in vitro using neuroblastoma (SH-SY5Y) cells. In vivo model, treatment with BF-7 significantly reduced the number of errors in 8-arm maze test and significantly increased latency time in passive avoidance test at 7 days after focal ischemia compared to those in the vehicle-treated group. In addition, treatment with BF-7 significantly decreased the infarct size or neuronal death at 7 day following transient ischemia compared to that in the vehicle-treated group. In vitro model, 10 or 20 μg/ml of BF-7 treatment significantly increased cell viability in dose-dependent manner. In addition, oxidative stress was significantly attenuated in the ischemic cells, showing that 10 or 20 μg/ml of BF-7 treatment significantly reduced the generation of reactive oxygen species (ROS) compared to that in the ischemic cells. These results indicate that BF-7 treatment can attenuate ischemic damages and improve memory deficits via reduction of ROS generation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s42826-020-00057-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7391609PMC
July 2020

Overexpressed p32 localized in the endoplasmic reticulum and mitochondria negatively regulates calcium‑dependent endothelial nitric oxide synthase activit.

Mol Med Rep 2020 Sep 6;22(3):2395-2403. Epub 2020 Jul 6.

Department of Biological Sciences, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea.

The p32 protein plays a crucial role in the regulation of cytosolic Ca2+ concentrations ([Ca2+]c) that contributes to the Ca2+‑dependent signaling cascade. Using an adenovirus and plasmid p32‑overexpression system, the aim of the study was to evaluate the role of p32 in the regulation of [Ca2+] and its potential associated with Ca2+‑dependent endothelial nitric oxide synthase (eNOS) activation in endothelial cells. Using electron and confocal microscopic analysis, p32 overexpression was observed to be localized to mitochondria and the endoplasmic reticulum and played an important role in Ca2+ translocation, resulting in increased [Ca2+] in these organelles and reducing cytosolic [Ca2+] ([Ca2+]c). This decreased [Ca2+]c following p32 overexpression attenuated the Ca2+‑dependent signaling cascade of calcium/calmodulin dependent protein kinase II (CaMKII)/AKT/eNOS phosphorylation. Moreover, in aortic endothelia of wild‑type mice intravenously administered adenovirus encoding the p32 gene, increased p32 levels reduced NO production and accelerated reactive oxygen species (ROS) generation. In a vascular tension assay, p32 overexpression decreased acetylcholine (Ach)‑induced vasorelaxation and augmented phenylephrine (PE)‑dependent vasoconstriction. Notably, decreased levels of arginase II (ArgII) protein using siArgII were associated with downregulation of overexpressed p32 protein, which contributed to CaMKII‑dependent eNOS phosphorylation at Ser1177. These results indicated that increased protein levels of p32 caused endothelial dysfunction through attenuation of the Ca2+‑dependent signaling cascade and that ArgII protein participated in the stability of p32. Therefore, p32 may be a novel target for the treatment of vascular diseases associated with endothelial disorders.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3892/mmr.2020.11307DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7411372PMC
September 2020

Long-Term Alternating Fasting Increases Interleukin-13 in the Gerbil Hippocampus, But Does Not Protect BBB and Pyramidal Neurons From Ischemia-Reperfusion Injury.

Neurochem Res 2020 Oct 15;45(10):2352-2363. Epub 2020 Jul 15.

Department of Biomedical Science and Research Institute for Bioscience and Biotechnology, Hallym University, Chuncheon, Gangwon, 24252, Republic of Korea.

It is questionable whether intermittent fasting (IF) protects against brain ischemic injury. This study examined whether IF increased anti-inflammatory cytokines and protected neurons from ischemia-reperfusion injury in the gerbil hippocampus. Gerbils were subjected to 1-day alternating fasting as IF for 1, 2, or 3 months and assigned to sham or 5 min of transient ischemia. We examined the changes in anti-inflammatory cytokines (IL-4 and IL-13), neurons and IgG by immunohistochemistry or immunofluorescence staining in the cornu ammonis 1 (CA1) region of the hippocampus before and after ischemia. IF increased IL-13 immunoreactivity in the CA1 region before ischemia, but did not affect IL-4 immunoreactivity. After ischemia, IL-13 and 4 immunoreactivities in the CA1 region were significantly lower in IF gerbils than in non-IF gerbils. In the IF gerbils, the CA1 pyramidal neurons were not protected from ischemic injury; in these gerbils, strong IgG immunoreactivity was seen in the CA1 parenchyma, indicating leakage of the BBB. In brief, IF increased IL-13 in the CA1 region, but these neurons were not protected from transient ischemic injury evidenced by IgG immunoreactivity in the CA1 parenchyma. This study indicates that IF increased some anti-inflammatory cytokines but did not afford neuroprotection against ischemic insults via BBB disruption.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11064-020-03094-zDOI Listing
October 2020

Laminarin Attenuates Ultraviolet-Induced Skin Damage by Reducing Superoxide Anion Levels and Increasing Endogenous Antioxidants in the Dorsal Skin of Mice.

Mar Drugs 2020 Jun 30;18(7). Epub 2020 Jun 30.

Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Korea.

A number of studies have demonstrated that marine carbohydrates display anti-oxidant, anti-melanogenic, and anti-aging activities in the skin. Laminarin (LA), a low-molecular-weight polysaccharide, is found in brown algae. The benefits of LA in ultraviolet B (UVB) induced photodamage of the skin have not been reported. The aim of this study was to investigate the effects of pre-treated LA on histopathological changes and oxidative damage in mouse dorsal skin on day 5, following repeated UVB exposure. Histopathology, Western blot analysis and immunohistochemical studies showed that epidermal thickness in the UVB group was significantly increased; however, the thickness in the UVB group treated with LA (LA/UVB group) was less compared with that of the UVB group. Collagen fibers in the dermis of the UVB group were significantly decreased and destroyed, whereas, in the LA/UVB group, the density of collagen fibers was significantly increased compared with that of the UVB group. Oxidative stress due to superoxide anion production measured via dihydroethidium fluorescence staining was dramatically increased in the UVB group, whereas in the LA/UVB group, the oxidative stress was significantly decreased. Expressions of SOD1, glutathione peroxidase and catalase were markedly reduced in the UVB group, whereas in the LA/UVB group, they were significantly higher along with SOD2 than in the control group. Taken together, our results indicate that LA pretreatment prevents or attenuates skin damage, by decreasing oxidative stress and increasing antioxidant enzymes in mouse dorsal skin.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/md18070345DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7401269PMC
June 2020

Age‑dependent alterations in the immunoreactivity of macrophage inflammatory protein‑3α and its receptor CCR6 in the gerbil hippocampus.

Mol Med Rep 2020 Aug 9;22(2):1317-1324. Epub 2020 Jun 9.

Department of Pharmacy, College of Pharmacy, Dankook University, Cheonan, Chungcheongnam 31116, Republic of Korea.

Neuroinflammation is a primary characteristic of the aging brain. During normal aging, macrophage inflammatory protein‑3α (MIP‑3α) and its receptor C‑C chemokine receptor type 6 (CCR6) serve pivotal roles in the neuroinflammatory process in the brain. The aim of the present study was to investigate age‑dependent alterations in the immunoreactivity of MIP‑3α and CCR6 in the gerbil hippocampus at postnatal month (PM) 1, 6, 12 and 24 via immunohistochemistry. In the PM 1 group, both MIP‑3α and CCR6 immunoreactivity were observed primarily in the stratum pyramidale in the hippocampus proper and in the granule cell layer in the dentate gyrus. In the PM 6 and PM 12 groups, MIP‑3α in the stratum pyramidale and granule cell layer was decreased compared with the PM 1 group, and CCR6 immunoreactivity in both layers was faint. In the PM 24 group, MIP‑3α expression in the stratum pyramidale and granule cell layer was higher than that in the PM 1 group, and CCR6 immunoreactivity in both layers was increased compared with the PM 12 group; however, it was decreased compared with the PM 1 group. In conclusion, MIP‑3α and CCR6 immunoreactivity were altered in the hippocampus during normal aging. The results of the current study suggested that age‑dependent alterations of MIP‑3α and CCR6 may be associated with age‑related neuroinflammation in the hippocampus.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3892/mmr.2020.11216DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7339448PMC
August 2020

Reduced Fecal Calprotectin and Inflammation in a Murine Model of Atopic Dermatitis Following Probiotic Treatment.

Int J Mol Sci 2020 May 31;21(11). Epub 2020 May 31.

Department of Dermatology, School of Medicine, Kangwon National University, Kangwon National University Hospital, Chuncheon 24341, Korea.

Atopic dermatitis (AD) is one of the most common skin diseases with inflammation, chronic relapses, and intense pruritus. Its pathogenesis includes genetic susceptibility, an abnormal epidermal lipid barrier, and an increased production of IgE due to immune dysregulation. Recently, AD has been reported to be associated with intestinal inflammation and dysbiosis in human and murine models. Various probiotics are being used to control intestinal dysbiosis and inflammatory reactions. However, it is difficult to predict or determine the therapeutic effects of the probiotics, since it is rare for clinicians to use the probiotics alone to treat AD. It is also difficult to check whether the intestinal inflammation in patients with AD has improved since probiotic treatment. The aim of the present study was to determine whether mice with induced atopic dermatitis had any changes in fecal calprotectin, an indicator of intestinal inflammation, after probiotic administration. Our results showed that the fecal calprotectin levels in mice with induced dermatitis decreased significantly after the administration of probiotics. In addition, epidermal skin lesions were attenuated and inflammatory-related cytokines were downregulated after the administration of probiotics in mice with induced dermatitis. These results suggest that changes in fecal calprotectin levels could be used to assess the effectiveness of a probiotic strain as an adjuvant treatment for AD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms21113968DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7312066PMC
May 2020

Comparison of neuronal death and expression of TNF‑α and MCT4 in the gerbil hippocampal CA1 region induced by ischemia/reperfusion under hyperthermia to those under normothermia.

Mol Med Rep 2020 Aug 22;22(2):1044-1052. Epub 2020 May 22.

Department of Pharmacy, College of Pharmacy, Dankook University, Cheonan, Chungcheongnam 31116, Republic of Korea.

Monocarboxylate transporter 4 (MCT4) is a high‑capacity lactate transporter in cells and the alteration in MCT4 expression harms cellular survival. The present study investigated whether hypothermia affects tumor necrosis factor‑α (TNF‑α) and MCT4 immunoreactivity in the subfield cornu ammonis 1 (CA1) following cerebral ischemia/reperfusion (IR) in gerbils. Hypothermia was induced for 30 min before and during ischemia. It was found that IR‑induced death of pyramidal neurons was markedly augmented and occurred faster under hyperthermia than under normothermia. TNF‑α immunoreactivity in the pyramidal cells started to increase at 3 h after IR and peaked at 1 day after IR under normothermia. However, in hyperthermic control and sham operated gerbils, TNF‑α immunoreactivity was significantly increased compared with the normothermic gerbils, and IR under hyperthermia caused a more rapid and significant increase in TNF‑α immunoreactivity in pyramidal neurons than under normothermia. In addition, in the normothermic gerbils, MCT4 immunoreactivity began to decrease in pyramidal neurons from 3 h after IR and markedly increased at 1 and 2 days after IR. On the other hand, MCT4 immunoreactivity in pyramidal neurons of the hyperthermic gerbils was significantly increased from 3 h after IR, maintained until 1 day after IR and markedly decreased at 2 days after IR. These results indicate that acceleration of IR‑induced neuronal death under hyperthermia might be closely associated with early alteration of TNF‑α and MCT4 protein expression in the gerbil hippocampus after IR.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3892/mmr.2020.11182DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7339721PMC
August 2020

Laminarin Pretreatment Provides Neuroprotection against Forebrain Ischemia/Reperfusion Injury by Reducing Oxidative Stress and Neuroinflammation in Aged Gerbils.

Mar Drugs 2020 Apr 15;18(4). Epub 2020 Apr 15.

Department of Neurobiology, School of Medicine, Kangwon National University, Chuncheon, Gangwon 24341, Korea.

Laminarin is a polysaccharide isolated from brown algae that has various biological and pharmacological activities, such as antioxidant and anti-inflammatory properties. We recently reported that pretreated laminarin exerted neuroprotection against transient forebrain ischemia/reperfusion (IR) injury when we pretreated with 50 mg/kg of laminarin once a day for seven days in adult gerbils. However, there have been no studies regarding a neuroprotective effect of pretreated laminarin against IR injury in aged animals and its related mechanisms. Therefore, in this study, we intraperitoneally inject laminarin (50 mg/kg) once a day to aged gerbils for seven days before IR (5-min transient ischemia) surgery and examine the neuroprotective effect of laminarin treatment and the mechanisms in the gerbil hippocampus. IR injury in vehicle-treated gerbils causes loss (death) of pyramidal neurons in the hippocampal CA1 field at five days post-IR. Pretreatment with laminarin effectively protects the CA1 pyramidal neurons from IR injury. Regarding the laminarin-treated gerbils, production of superoxide anions, 4-hydroxy-2-nonenal expression and pro-inflammatory cytokines [interleukin(IL)-1β and tumor necrosis factor-α] expressions are significantly decreased in the CA1 pyramidal neurons after IR. Additionally, laminarin treatment significantly increases expressions of superoxide dismutase and anti-inflammatory cytokines (IL-4 and IL-13) in the CA1 pyramidal neurons before and after IR. Taken together, these findings indicate that laminarin can protect neurons from ischemic brain injury in an aged population by attenuating IR-induced oxidative stress and neuroinflammation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/md18040213DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7230782PMC
April 2020