Publications by authors named "Soo Jin Choi"

158 Publications

Interaction between ZnO Nanoparticles and Albumin and Its Effect on Cytotoxicity, Cellular Uptake, Intestinal Transport, Toxicokinetics, and Acute Oral Toxicity.

Nanomaterials (Basel) 2021 Oct 31;11(11). Epub 2021 Oct 31.

Division of Applied Food System, Major of Food Science & Technology, Seoul Women's University, Seoul 01797, Korea.

Zinc oxide (ZnO) nanoparticles (NPs) are used as zinc supplements due to the nutritional value of Zn. The toxicity of ZnO NPs in the food industry is required to be elucidated because they have large surface area and high reactivity compared with bulk-sized materials and have potentials to interact with food matrices, which may lead to different biological responses. In this study, interactions between ZnO NPs and food proteins (albumin, casein, and zein) were evaluated by measuring changes in physicochemical property, fluorescence quenching ratios, and structural protein stability compared with ZnO interaction with glucose, the most interacted saccharide in our previous report. The interaction effects on cytotoxicity, cellular uptake, intestinal transport, toxicokinetics, and acute oral toxicity were also investigated. The results demonstrate that interaction between ZnO and albumin reduced hydrodynamic diameters, but increased cytotoxicity, cellular uptake, and intestinal transport in a similar manner to ZnO interaction with glucose, without affecting primary structural protein stability and toxicokinetic behaviors. Hematological, serum biochemical, and histopathological analysis reveal no toxicological findings after orally administered ZnO NPs interacted with albumin or glucose in rats for 14 consecutive days, suggesting their low oral toxicity. In conclusion, the interactions between ZnO NPs and food proteins modulate in vitro biological responses, but do not affect in vivo acute oral toxicity. Further study is required to ascertain the interaction effects on chronic oral toxicity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/nano11112922DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8625151PMC
October 2021

Characterization and Determination of Nanoparticles in Commercial Processed Foods.

Foods 2021 Aug 28;10(9). Epub 2021 Aug 28.

Division of Applied Food System, Major of Food Science & Technology, Seoul Women's University, Seoul 01797, Korea.

A wide variety of foods manufactured by nanotechnology are commercially available on the market and labeled as nanoproducts. However, it is challenging to determine the presence of nanoparticles (NPs) in complex food matrices and processed foods. In this study, top-down-approach-produced (TD)-NP products and nanobubble waters (NBWs) were chosen as representative powdered and liquid nanoproducts, respectively. The characterization and determination of NPs in TD-NP products and NBWs were carried out by measuring constituent particle sizes, hydrodynamic diameters, zeta potentials, and surface chemistry. The results show that most NBWs had different characteristics compared with those of conventional sparkling waters, but nanobubbles were unstable during storage. On the other hand, powdered TD-NP products were found to be highly aggregated, and the constituent particle sizes less than 100 nm were remarkably observed after dispersion compared with counterpart conventional bulk-sized products by scanning electron microscopy at low acceleration voltage and cryogenic transmission electron microscopy. The differences in chemical composition and chemical state between TD-NPs and their counterpart conventional bulk products were also found by X-ray photoelectron spectroscopy. These findings will provide basic information about the presence of NPs in nano-labeled products and be useful to understand and predict the potential toxicity of NPs applied to the food industry.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/foods10092020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8465140PMC
August 2021

PTX-3 Secreted by Intra-Articular-Injected SMUP-Cells Reduces Pain in an Osteoarthritis Rat Model.

Cells 2021 09 14;10(9). Epub 2021 Sep 14.

Biomedical Research Institute, MEDIPOST Co., Ltd., Seongnam-si 13494, Korea.

Mesenchymal stem cells (MSCs) are accessible, abundantly available, and capable of regenerating; they have the potential to be developed as therapeutic agents for diseases. However, concerns remain in their further application. In this study, we developed a SMall cell+Ultra Potent+Scale UP cell (SMUP-Cell) platform to improve whole-cell processing, including manufacturing bioreactors and xeno-free solutions for commercialization. To confirm the superiority of SMUP-Cell improvements, we demonstrated that a molecule secreted by SMUP-Cells is capable of polarizing inflammatory macrophages (M1) into their anti-inflammatory phenotype (M2) at the site of injury in a pain-associated osteoarthritis (OA) model. Lipopolysaccharide-stimulated macrophages co-cultured with SMUP-Cells expressed low levels of M1-phenotype markers (CD11b, tumor necrosis factor-α, interleukin-1α, and interleukin-6), but high levels of M2 markers (CD163 and arginase-1). To identify the paracrine action underlying the anti-inflammatory effect of SMUP-Cells, we employed a cytokine array and detected increased levels of pentraxin-related protein-3 (PTX-3). Additionally, mRNA silencing was applied to confirm PTX-3 function. silencing in SMUP-Cells significantly decreased their therapeutic effects against monosodium iodoacetate (MIA)-induced OA. Thus, PTX-3 expression in injected SMUP-Cells, applied as a therapeutic strategy, reduced pain in an OA model.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/cells10092420DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8466059PMC
September 2021

Intracerebroventricular injection of human umbilical cord blood mesenchymal stem cells in patients with Alzheimer's disease dementia: a phase I clinical trial.

Alzheimers Res Ther 2021 09 14;13(1):154. Epub 2021 Sep 14.

Departments of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 80 Ilwon-ro, Gangnam-gu, Seoul, 135-710, Republic of Korea.

Backgrounds: Alzheimer's disease is the most common cause of dementia, and currently, there is no disease-modifying treatment. Favorable functional outcomes and reduction of amyloid levels were observed following transplantation of mesenchymal stem cells (MSCs) in animal studies.

Objectives: We conducted a phase I clinical trial in nine patients with mild-to-moderate Alzheimer's disease dementia to evaluate the safety and dose-limiting toxicity of three repeated intracerebroventricular injections of human umbilical cord blood-derived MSCs (hUCB-MSCs).

Methods: We recruited nine mild-to-moderate Alzheimer's disease dementia patients from Samsung Medical Center, Seoul, Republic of Korea. Four weeks prior to MSC administration, the Ommaya reservoir was implanted into the right lateral ventricle of the patients. Three patients received a low dose (1.0 × 10 cells/2 mL), and six patients received a high dose (3.0 × 10 cells/2 mL) of hUCB-MSCs. Three repeated injections of MSCs were performed (4-week intervals) in all nine patients. These patients were followed up to 12 weeks after the first hUCB-MSC injection and an additional 36 months in the extended observation study.

Results: After hUCB-MSC injection, the most common adverse event was fever (n = 9) followed by headache (n = 7), nausea (n = 5), and vomiting (n = 4), which all subsided within 36 h. There were three serious adverse events in two participants that were considered to have arisen from the investigational product. Fever in a low dose participant and nausea with vomiting in another low dose participant each required extended hospitalization by a day. There were no dose-limiting toxicities. Five participants completed the 36-month extended observation study, and no further serious adverse events were observed.

Conclusions: Three repeated administrations of hUCB-MSCs into the lateral ventricle via an Ommaya reservoir were feasible, relatively and sufficiently safe, and well-tolerated. Currently, we are undergoing an extended follow-up study for those who participated in a phase IIa trial where upon completion, we hope to gain a deeper understanding of the clinical efficacy of MSC AD therapy.

Trial Registration: ClinicalTrials.gov NCT02054208. Registered on 4 February 2014. ClinicalTrials.gov NCT03172117. Registered on 1 June 2017.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13195-021-00897-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8439008PMC
September 2021

An anastomosing hemangioma mimicking a renal cell carcinoma in a kidney transplant recipient: a case report.

BMC Nephrol 2021 07 13;22(1):262. Epub 2021 Jul 13.

Department of Internal Medicine, Chonnam National University Medical School, 160 Baekseo-ro, Dong-gu, Gwangju, 61469, South Korea.

Background: Although anastomosing hemangiomas are very rare and benign vascular neoplasms, these tumors are more common among patients with end-stage kidney disease. Incidental finding of these tumors in the kidney or adrenal gland has been reported. Herein, we describe a case in which an anastomosing hemangioma was misdiagnosed as a renal cell carcinoma before kidney transplant.

Case Presentation: A 35-year-old woman with lupus nephritis was admitted to our emergency department for suspected uremic symptoms of nausea and general weakness. She had received hemodialysis due to end-stage kidney disease, and a living-donor kidney transplantation from her father was planned. On pre-operative contrast-enhanced computed tomography and magnetic resonance imaging, a 1.7 cm renal cell carcinoma was observed in the right kidney. On staining after radical nephrectomy, irregularly shaped vascular spaces of various sizes were observed, with these spaces having an anastomosing pattern. As the findings of the anastomosing hemangioma are similar to those of a renal cell carcinoma on imaging, histology examination was necessary to confirm the diagnosis of anastomosing hemangioma and to prevent delay in listing for kidney transplantation. Good kidney function was achieved after transplantation, with no tumor recurrence.

Conclusion: Our case underlines the importance for prompt surgical resection of an enhancing renal mass to confirm diagnosis in patients scheduled for kidney transplantation to avoid any delay.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12882-021-02467-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8278676PMC
July 2021

Determination of Two Differently Manufactured Silicon Dioxide Nanoparticles by Cloud Point Extraction Approach in Intestinal Cells, Intestinal Barriers and Tissues.

Int J Mol Sci 2021 Jun 29;22(13). Epub 2021 Jun 29.

Division of Applied Food System, Major of Food Science & Technology, Seoul Women's University, Seoul 01797, Korea.

Food additive amorphous silicon dioxide (SiO) particles are manufactured by two different methods-precipitated and fumed procedures-which can induce different physicochemical properties and biological fates. In this study, precipitated and fumed SiO particles were characterized in terms of constituent particle size, hydrodynamic diameter, zeta potential, surface area, and solubility. Their fates in intestinal cells, intestinal barriers, and tissues after oral administration in rats were determined by optimizing Triton X-114-based cloud point extraction (CPE). The results demonstrate that the constituent particle sizes of precipitated and fumed SiO particles were similar, but their aggregate states differed from biofluid types, which also affect dissolution properties. Significantly higher cellular uptake, intestinal transport amount, and tissue accumulation of precipitated SiO than of fumed SiO was found. The intracellular fates of both types of particles in intestinal cells were primarily particle forms, but slowly decomposed into ions during intestinal transport and after distribution in the liver, and completely dissolved in the bloodstream and kidneys. These findings will provide crucial information for understanding and predicting the potential toxicity of food additive SiO after oral intake.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms22137035DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8268481PMC
June 2021

Positively Correlated CD47 Activation and Autophagy in Umbilical Cord Blood-Derived Mesenchymal Stem Cells during Senescence.

Stem Cells Int 2021 15;2021:5582792. Epub 2021 Apr 15.

Biomedical Research Institute, MEDIPOST Co., Ltd., Seongnam 13494, Republic of Korea.

Autophagy plays a critical role in stem cell maintenance and is related to cell growth and cellular senescence. It is important to find a quality-control marker for predicting senescent cells. This study verified that CD47 could be a candidate to select efficient mesenchymal stem cells (MSCs) to enhance the therapeutic effects of stem cell therapy by analyzing the antibody surface array. CD47 expression was significantly decreased during the expansion of MSCs in vitro ( < 0.01), with decreased CD47 expression correlated with accelerated senescence phenotype, which affected cell growth. UCB-MSCs transfected with CD47 siRNA significantly triggered the downregulation of pRB and upregulation of pp38, which are senescence-related markers. Additionally, autophagy-related markers, ATG5, ATG12, Beclin1, and LC3B, revealed significant downregulation with CD47 siRNA transfection. Furthermore, autophagy flux following treatment with an autophagy inducer, rapamycin, has shown that CD47 is a key player in autophagy and senescence to maintain and regulate the growth of MSCs, suggesting that CD47 may be a critical key marker for the selection of effective stem cells in cell therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1155/2021/5582792DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8062176PMC
April 2021

Antithrombotic therapy has no beneficial effect in conservative treatment of spontaneous isolated superior mesenteric arterial dissection.

Ann Surg Treat Res 2021 Mar 26;100(3):166-174. Epub 2021 Feb 26.

Division of Vascular and Transplant Surgery, Department of Surgery, Chonnam National University Medical School, Gwangju, Korea.

Purpose: Initial conservative treatment with selective endovascular or surgical intervention has shown successful outcomes in the treatment of spontaneous isolated superior mesenteric artery dissection (SISMAD). However, the benefits of antithrombotic therapy as a part of conservative treatment have not been clarified. This study aimed to investigate the clinical course of SISMAD patients and determine differences in clinical outcomes between the antithrombotic and no-antithrombotic groups.

Methods: We retrospectively reviewed 79 cases of SISMAD that were treated conservatively from January 2004 to December 2019 at Chonnam National University Hospital. Clinical outcomes, including the length of hospital stay, pain resolution time, image remodeling, and maximal remodeling time, were compared between the antithrombotic and no-antithrombotic groups.

Results: There were 30 patients in the no-antithrombotic group and 49 patients in the antithrombotic group. There was no significant difference in clinical characteristics between the 2 groups, except for dyslipidemia (P = 0.011). The follow-up period (32.6 months 14.6 months, P = 0.009) and imaging follow-up period (31.6 months 13.9 months, P = 0.011) were longer in the antithrombotic group than in the no-antithrombotic group. The length of hospital stay (5.1 days 7.7 days, P = 0.002) was significantly shorter in the no-antithrombotic group than in the antithrombotic group because patients in the antithrombotic group required longer hospitalization for warfarin titration.

Conclusion: In patients with SISMAD, conservative treatment without antithrombotic therapy may have clinical benefits such as decreased length of hospital stay compared with conservative treatment with antithrombotic therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4174/astr.2021.100.3.166DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7943285PMC
March 2021

Particle Size and Biological Fate of ZnO Do Not Cause Acute Toxicity, but Affect Toxicokinetics and Gene Expression Profiles in the Rat Livers after Oral Administration.

Authors:
Jin Yu Soo-Jin Choi

Int J Mol Sci 2021 Feb 8;22(4). Epub 2021 Feb 8.

Division of Applied Food System, Major of Food Science and Technology, Seoul Women's University, Seoul 01797, Korea.

Zinc oxide (ZnO) particles have been used as dietary supplements because zinc is an essential trace element for humans. Along with the rapid development of nanotechnology, the use of ZnO nanoparticles (NPs) is increasing in the food industry, but their oral toxicity potential still remains to be answered. In this study, the effects of particle size and biological fate of ZnO on acute toxicity, toxicokinetics, and gene expression profiles in the livers were investigated after oral administration of ZnO NPs (N-ZnO), bulk-sized ZnO (B-ZnO) or Zn ions in rats. The plasma concentration-time profiles after a single-dose oral administration of ZnOs differed depending on particle/ionic forms and particle size, showing high absorption of Zn ions, followed by N-ZnO and B-ZnO, although in vivo solubility did not differ from particle size. No significant acute toxicity was found after oral administration of ZnOs for 14 days in rats. However, transcriptomic responses in the livers were differently affected, showing that metabolic process and metal biding were up-regulated by Zn ions and N-ZnO, respectively, which were not pronounced in the liver treated with B-ZnO. These findings will be useful to predict the potential oral toxicity of ZnO NPs and further mechanistic and long-term exposure studies are required to assume their safety.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms22041698DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7915389PMC
February 2021

Prospects for the therapeutic development of umbilical cord blood-derived mesenchymal stem cells.

World J Stem Cells 2020 Dec;12(12):1511-1528

Biomedical Research Institute, MEDIPOST Co., Ltd., Seongnam 13494, South Korea.

Umbilical cord blood (UCB) is a primitive and abundant source of mesenchymal stem cells (MSCs). UCB-derived MSCs have a broad and efficient therapeutic capacity to treat various diseases and disorders. Despite the high latent self-renewal and differentiation capacity of these cells, the safety, efficacy, and yield of MSCs expanded for clinical applications remains a concern. However, immunomodulatory effects have emerged in various disease models, exhibiting specific mechanisms of action, such as cell migration and homing, angiogenesis, anti-apoptosis, proliferation, anti-cancer, anti-fibrosis, anti-inflammation and tissue regeneration. Herein, we review the current literature pertaining to the UCB-derived MSC application as potential treatment strategies, and discuss the concerns regarding the safety and mass production issues in future applications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.4252/wjsc.v12.i12.1511DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7789129PMC
December 2020

High Integrity and Fidelity of Long-Term Cryopreserved Umbilical Cord Blood for Transplantation.

J Clin Med 2021 Jan 14;10(2). Epub 2021 Jan 14.

Biomedical Research Institute, MEDIPOST Co., Ltd., Seongnam-si, Gyeonggi-do 13494, Korea.

Umbilical cord blood (UCB) is used as a source of donor cells for hematopoietic stem cell (HSC) transplantation. The success of transplantation is dependent on the quality of cord blood (CB) units for maximizing the chance of engraftment. Improved outcomes following transplantation are associated with certain factors of cryopreserved CB units: total volume and total nucleated cell (TNC) count, mononuclear cell (MNC) count, and CD34+ cell count. The role of the storage period of CB units in determining the viability and counts of cells is less clear and is related to the quality of cryopreserved CB units. Herein, we demonstrate the recovery of viable TNCs and CD34+ cells, as well as the MNC viability in 20-year-old cryopreserved CB units in a CB bank (MEDIPOST Co., Ltd., Seongnam-si, Gyeonggi-do, Korea). In addition, cell populations in CB units were evaluated for future clinical applications. The stable recovery rate of the viability of cryopreserved CB that had been stored for up to 20 years suggested the possibility of uses of the long-term cryopreservation of CB units. Similar relationships were observed in the recovery of TNCs and CD34+ cells in units of cryopreserved and fresh CB. The high-viability recovery of long-term cryopreserved CB suggests that successful hematopoietic stem cell (HSC) transplantation and other clinical applications, which are suitable for treating incurable diseases, may be performed regardless of long-term storage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/jcm10020293DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7830419PMC
January 2021

Improving the Stability and Curcumin Retention Rate of Curcumin-Loaded Filled Hydrogel Prepared Using 4αGTase-Treated Rice Starch.

Foods 2021 Jan 13;10(1). Epub 2021 Jan 13.

Department of Biosystems Engineering, Seoul National University, Seoul 08826, Korea.

In this study, 4-α-glucanotransferase (4αGTase)-treated rice starch (GS) was added after 1-h (1 GS) and 96-h (96 GS) treatments to the aqueous phase of a curcumin-loaded emulsion to produce filled hydrogels (1 GS-FH and 96 GS-FH, respectively). The relative protective effects of the FH system, native rice starch-based filled hydrogel (RS-FH), and emulsion without starch (EM), on curcumin were evaluated based on ultraviolet (UV) stability and simulated gastrointestinal studies. The UV stability and curcumin retention after in vitro digestion of the filled hydrogels (FH) samples were greater than those of the EM samples. RS-FH showed a 2.28-fold improvement in UV stability over EM due to the higher viscosity of RS. 1 GS-FH and 96 GS-FH increased curcumin retention by 2.31- and 2.60-fold, respectively, and the microstructure of 96 GS-FH, determined using confocal laser microscopy, remained stable even after the stomach phase. These effects were attributed to the molecular structure of GS, with decreased amylopectin size and amylose content resulting from the enzyme treatment. The encapsulation of lipids within the GS hydrogel particles served to protect and deliver the curcumin component, suggesting that GS-FH can be applied to gel-type food products and improve the chemical stability of curcumin.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/foods10010150DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7828239PMC
January 2021

Senescence-Associated Secretory Phenotype Suppression Mediated by Small-Sized Mesenchymal Stem Cells Delays Cellular Senescence through TLR2 and TLR5 Signaling.

Cells 2021 01 3;10(1). Epub 2021 Jan 3.

Biomedical Research Institute, MEDIPOST Co., Ltd., Seongnam 13494, Korea.

In order to provide a sufficient number of cells for clinical use, mesenchymal stem cells (MSCs) must be cultured for long-term expansion, which inevitably triggers cellular senescence. Although the small size of MSCs is known as a critical determinant of their fate, the main regulators of stem cell senescence and the underlying signaling have not been addressed. Umbilical cord blood-derived MSCs (UCB-MSCs) were obtained using size-isolation methods and then cultured with control or small cells to investigate the major factors that modulate MSC senescence. Cytokine array data suggested that the secretion of interukin-8 (IL-8) or growth-regulated oncogene-alpha (GROa) by senescent cells was markedly inhibited during incubation of small cells along with suppression of cognate receptor (C-X-C motif chemokine receptor2, CXCR2) via blockade of the autocrine/paracrine positive loop. Moreover, signaling via toll-like receptor 2 (TLR2) and TLR5, both pattern recognition receptors, drove cellular senescence of MSCs, but was inhibited in small cells. The activation of TLRs (2 and 5) through ligand treatment induced a senescent phenotype in small cells. Collectively, our data suggest that small cell from UCB-MSCs exhibit delayed cellular senescence by inhibiting the process of TLR signaling-mediated senescence-associated secretory phenotype (SASP) activation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/cells10010063DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7824096PMC
January 2021

Pharmacokinetics and Protective Effects of Tartary Buckwheat Flour Extracts against Ethanol-Induced Liver Injury in Rats.

Antioxidants (Basel) 2020 Sep 24;9(10). Epub 2020 Sep 24.

Division of Applied Food System, Major of Food Science & Technology, Seoul Women's University, Seoul 01797, Korea.

The grains of Tartary buckwheat () are traditionally consumed on a daily basis and are used in the preparation of diverse processed foods owing to the high concentration of rutin, an antioxidant compound. However, rutin is highly concentrated in hull and bran, but not in edible flour fractions. Rutin-enriched TB flour extracts (TBFEs) were obtained by hydrothermal treatment (autoclaving, boiling, or steaming) and their pharmacokinetic profiles were evaluated following a single-dose oral administration in rats. The antioxidant and protective activities of the extracts against alcoholic liver disease (ALD) were investigated after repetitive oral administration of TBFEs for 28 days prior to ethanol ingestion. The results demonstrated that rutin-enriched TBFEs had better oral absorption and was retained longer in the bloodstream than native TBFE or standard rutin. The activities of antioxidant enzymes and intracellular antioxidant levels increased in ALD rats following TBFE treatments, especially following the administration of rutin-enriched TBFEs. The antioxidant activity of TBFEs consequently contributed toward protecting the liver against injury caused by repetitive ethanol administration, as confirmed by analyzing relative liver weight, liver injury markers, lipid peroxidation, and calcium permeability. These results suggest the promising potential of TBFEs as antioxidant-enriched functional foods for human health.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/antiox9100913DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7599602PMC
September 2020

Deceased vs. living donor kidney transplantation in prediction of acute renal allograft rejection using Tc-99m DTPA renal scan.

Ann Nucl Med 2020 Nov 12;34(11):847-855. Epub 2020 Sep 12.

Department of Nuclear Medicine, Chonnam National University Hospital, Gwangju, Korea.

Objectives: No data are available regarding different prognostic values of Tc-99m diethylenetriaminepentaacetic acid (DTPA) renal scan in kidney transplantation (KT) recipients according to two distinct donor types: deceased donor KT (DDKT) and living donor KT (LDKT). We evaluated whether the interpretation of Tc-99m DTPA renal scan should be different by the donor type in predicting acute renal allograft rejection (AR).

Methods: One hundred and seven KT recipients (61 DDKT and 46 LDKT) were included in this study. Tc-99m DTPA renal scan was performed 1 week after KT. AR was defined as pathological evidence of renal allograft rejection during the first 6 months of KT. Clinical factors and Tc-99m DTPA renal scan findings were compared between patients with and without AR. To further analyze the effect of the donor type, they were again compared within DDKT and LDKT recipients, respectively.

Results: AR occurred in 15 patients (7 DDKT and 8 LDKT recipients). Among all patients, time to peak uptake (TTP) of the cortex (TTP) measured by Tc-99m DTPA renal scan was independently predictive of AR. Moreover, TTP (TTP of the whole transplanted kidney) and TTP were the only predictors of AR among DDKT recipients. The most accurate predictors were TTP and kidney area on renal scan for DDKT and LDKT, respectively. However, these parameters could not predict AR for the opposite donor type.

Conclusions: AR could be effectively predicted by Tc-99m DTPA renal scan obtained at 1 week post-KT. Different parameters should be applied according to the donor type in the prediction of AR.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12149-020-01511-5DOI Listing
November 2020

Galectin-3 Secreted by Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Reduces Aberrant Tau Phosphorylation in an Alzheimer Disease Model.

Stem Cells Int 2020 18;2020:8878412. Epub 2020 Jul 18.

Biomedical Research Institute, R&D Center, MEDIPOST Co., Ltd., Gyeonggi-do, Republic of Korea.

The formation of neurofibrillary tangles has been implicated as an important pathological marker for Alzheimer's disease (AD). Studies have revealed that the inhibition of abnormal hyperphosphorylation and aggregation of tau in the AD brain might serve as an important drug target. Using and experimental models, such as the AD mouse model (5xFAD mice), we investigated the inhibition of hyperphosphorylation of tau using the human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs). Administration of hUCB-MSCs not only ameliorated the spatial learning and memory impairments but also mitigated the hyperphosphorylation of tau in 5xFAD mice. Furthermore, experiments in mice and ThT fluorescence assay validated galectin-3 (GAL-3) as an essential factor of hUCB-MSC. Moreover, GAL-3 was observed to be involved in the removal of aberrant forms of tau, by reducing hyperphosphorylation through decrements in the glycogen synthase kinase 3 beta (GSK-3). Our results confirm that GAL-3, secreted by hUCB-MSC, regulates the abnormal accumulation of tau by protein-protein interactions. This study suggests that hUCB-MSCs mitigate hyperphosphorylation of tau through GAL-3 secretion. These findings highlight the potential role of hUCB-MSCs as a therapeutic agent for aberrant tau in AD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1155/2020/8878412DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7383310PMC
July 2020

Determination of the fate and biological responses of food additive silica particles in commercial foods.

Food Chem 2020 Nov 10;331:127304. Epub 2020 Jun 10.

Division of Applied Food System, Major of Food Science & Technology, Seoul Women's University, Seoul 01797, Republic of Korea. Electronic address:

Synthetic amorphous silica (SAS) is widely added to commercial foods as an anticaking agent. Concern about the potential application of nanosized silica in foods has increased as nanomaterials are not intended for use as food additives. This study evaluated the particle size distributions and biological responses of food additive SAS. An accurate, sensitive, and cost-effective analytical method for probing SAS was established, and quantitative analysis of its presence in commercial foods was performed. The results demonstrate that food additive SAS is an aggregated material composed of nanosized particles with nanosized aggregates of silica particles identified in commercial foods. Food additive SAS did not exhibit acute cytotoxicity compared to both general-grade nano (G-nano) and bulk (G-bulk) silica. Moreover, intestinal transport amounts of food additive SAS were significantly lower than for G-nano. Taken together, we find that food additive SAS does not exhibit acute toxicity resulting from nanosized materials.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.foodchem.2020.127304DOI Listing
November 2020

Migration Inhibitory Factor in Conditioned Medium from Human Umbilical Cord Blood-Derived Mesenchymal Stromal Cells Stimulates Hair Growth.

Cells 2020 05 28;9(6). Epub 2020 May 28.

Biomedical Research Institute, MEDIPOST Co., Ltd., Seongnam 13494, Korea.

Conventional therapeutic applications of mesenchymal stromal cells (MSCs) focus on cell replacement and differentiation; however, increasing evidence suggests that most of their therapeutic effects are carried out by their various secretions. This study investigated the application of conditioned medium (CM) from human umbilical cord blood-derived MSCs (hUCB-MSCs) to improve hair growth and developed a method to reliably produce this optimized CM. Primed MSC-derived CM (P-CM) with combinations of TGF-β1 and LiCl was optimized by comparing its effects on the cell viability of dermal papilla cells (DPCs). P-CM significantly increased the viability of DPCs compared to CM. The secretion of vascular endothelial growth factor (VEGF) in DPCs was regulated by the macrophage migration inhibitory factor (MIF) in the P-CM secreted by MSCs. These findings suggest that P-CM can improve the efficacy in hair growth via a paracrine mechanism and that MIF in P-CM exerts hair growth-promoting effects via a VEGF-related β-catenin and p-GSK-3β [SER9] signaling pathway. Furthermore, clinical trials have shown that 5% P-CM improved androgenetic alopecia through producing an increased hair density, thickness, and growth rate, suggesting that this topical agent may be a novel and effective treatment option for patients with androgenetic alopecia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/cells9061344DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7349163PMC
May 2020

A Small-Sized Population of Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Shows High Stemness Properties and Therapeutic Benefit.

Stem Cells Int 2020 28;2020:5924983. Epub 2020 Apr 28.

Biomedical Research Institute, MEDIPOST Co., Ltd., Seongnam 13494, Republic of Korea.

Mesenchymal stem cells (MSCs) represent a promising means to promote tissue regeneration. However, the heterogeneity of MSCs impedes their use for regenerative medicine. Further investigation of this phenotype is required to develop cell therapies with improved clinical efficacy. Here, a small-sized population of human umbilical cord blood-derived MSCs (UCB-MSCs) was isolated using a filter and centrifuge system to analyze its stem cell characteristics. Consequently, this population showed higher cell growth and lower senescence. Additionally, it exhibited diverse stem cell properties including differentiation, stemness, and adhesion, as compared to those of the population before isolation. Using cell surface protein array or sorting analysis, both EGFR and CD49f were identified as markers associated with the small-sized population. Accordingly, suppression of these surface proteins abolished the superior characteristics of this population. Moreover, compared to that with large or nonisolated populations, the small-sized population showed greater therapeutic efficacy by promoting the engraftment potential of infused cells and reducing lung damage in an emphysema mouse model. Therefore, the isolation of this small-sized population of UCB-MSCs could be a simple and effective way to enhance the efficacy of cell therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1155/2020/5924983DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7204153PMC
April 2020

Soluble PTX3 of Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Attenuates Hyperoxic Lung Injury by Activating Macrophage Polarization in Neonatal Rat Model.

Stem Cells Int 2020 23;2020:1802976. Epub 2020 Jan 23.

Biomedical Research Institute, MEDIPOST Co., Ltd., Seongnam 13494, Republic of Korea.

Therapeutic treatment of various inflammation-related diseases using mesenchymal stem cells (MSCs) has increased in recent years because of the paracrine action of these cells but shows several limitations. First, MSC-based therapies exhibit varying efficacies; thus, biomarkers should be determined to identify who may benefit from these candidate therapeutic agents. Second, the mechanism underlying the therapeutic effects is poorly understood. To evaluate the effects of human umbilical cord blood-derived MSCs (UCB-MSCs) on macrophages, the macrophage cell line NR8383 stimulated with lipopolysaccharide (LPS) was cocultured by UCB-MSCs. We found that UCB-MSCs mediated changes in macrophage polarization towards M2 from M1 macrophages. To identify the paracrine action underlying the anti-inflammation effect of UCB-MSCs, the secretion of UCB-MSCs exposed to LPS-stimulated NR8383 cells was tested using a biotin label-based 507 antibody array. Among the secreted proteins, we selected pentraxin-related protein PTX3/tumor necrosis factor-inducible gene 14 protein (PTX3) to investigate its association with UCB-MSCs in macrophage polarization. We found that human PTX3 was secreted from UCB-MSCs under inflammation condition and reinforced the M2 macrophage marker via the Dectin-1 receptor by activating MSK1/2 phosphorylation signaling in NR8383 cells. Accordingly, knockdown of PTX3 in UCB-MSCs significantly attenuated their therapeutic effects in a neonatal hyperoxic lung injury resulting in reduced survival, lung alveolarization, M2 marker expression, Dectin-1 levels, anti-inflammatory cytokines, and improved M1 marker expression and inflammatory cytokines compared to control MSC-injected rats. UCB-MSCs show therapeutic potential by controlling macrophage polarization. Interestingly, higher PTX3 levels in UCB-MSCs induced greater improvement in the therapeutic effects than lower PTX3 levels. Collectively, PTX3 is a potential marker with critical paracrine effects for predicting the therapeutic potential of MSC therapy in inflammatory diseases; quality control assessments using PTX3 may be useful for improving the therapeutic effects of UCB-MSCs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1155/2020/1802976DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7204119PMC
January 2020

Charge-switchable magnetic separation and characterization of food additive titanium dioxide nanoparticles from commercial food.

J Hazard Mater 2020 07 6;393:122483. Epub 2020 Mar 6.

Graduate School of Biotechnology & Department of Food Science and Biotechnology, College of Life Sciences, Kyung Hee University, Yongin, 17104, South Korea. Electronic address:

Growing concerns about the potential health effects of nanoscale titanium dioxide (TiO) have necessitated the need for monitoring the size distribution and physicochemical properties of food additive TiO that are present in commercial food. Acid digestion is by far the most widely used method to remove interfering food matrices, but the highly corrosive nature of the reaction could alter the physicochemical properties of the TiO, which may give a skewed information about the materials. Here, we report an effective approach to extract intact form of food additive TiO nanoparticles from processed food through charge-charge interaction between TiO particles and charge-switchable starch magnetic beads ([email protected]), of which the captured TiO is readily harvested by switching the surface charge of [email protected] to neutral. The size and surface property of extracted TiO were shown to be well maintained due to the mild nature of the reaction. The extracted TiO particles from 10 commercial processed food showed a size distribution from 40 to 250 nm with a mean diameter of 115 nm, of which 22 % of them were less than 100 nm. The extracted TiO did not exhibit short-term cytotoxicity, but induced cellular oxidative stress at high concentration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jhazmat.2020.122483DOI Listing
July 2020

Primary Cilia Mediate Wnt5a/β-catenin Signaling to Regulate Adipogenic Differentiation of Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Following Calcium Induction.

Tissue Eng Regen Med 2020 04 1;17(2):193-202. Epub 2020 Feb 1.

Biomedical Research Institute, MEDIPOST Co. Ltd, 21, Daewangpangyo-ro 644-gil, Bundang-gu, Seongnam-si, Gyeonggi-do, 13494, Korea.

Background: Regeneration of soft tissue defects is essential for adipose tissue pathologies and disease, trauma, or injury-induced damage. Here, we show that umbilical cord blood-derived mesenchymal stem cells could potentially be tailored and used for the reconstruction of specific damaged sites. Adipogenesis can be exploited in soft tissue reconstruction. Also, primary cilia play a role in the control of adipogenesis.

Methods: The adipogenic differentiation capacity of mesenchymal stem cells (MSCs) was shown to influence ciliogenesis. MSCs transfected with intraflagellar transport 88 (IFT88) small interfering RNA (siRNA), which blocks the assembly and maintenance of cilia, were examined to confirm the relationship between adipogenesis and ciliogenesis. Also, 1,2-Bis(2-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid tetrakis(acetoxymethyl ester) (BAPTA-AM), calcium chelator, inhibited the ciliogenesis of MSCs in adipogenic differentiation.

Results: IFT88-knockdown led to decreased cilia formation and limitation of cilia elongation in adipogenesis. Additionally, intracellular calcium triggered cilia formation in MSCs adipogenesis. Interestingly, intracellular calcium cannot overcome the inhibition of adipogenesis caused by low numbers of cilia in MSCs.

Conclusion: Our data suggested that ciliogenesis was negatively regulated by Wnt5a/β-catenin signaling during adipogenesis. Thus, we suggest that calcium induction triggers adipogenesis and ciliogenesis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s13770-019-00237-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7105559PMC
April 2020

Up-Regulation of Superoxide Dismutase 2 in 3D Spheroid Formation Promotes Therapeutic Potency of Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells.

Antioxidants (Basel) 2020 Jan 11;9(1). Epub 2020 Jan 11.

Biomedical Research Institute, MEDIPOST Co., Ltd., Seongnam 13494, Korea.

Umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) are accessible, available in abundance, and have been shown to be a promising source that can regenerate cartilage in patients with osteoarthritis or other orthopedic diseases. Recently, a three-dimensional (3D) cell culture system was developed to mimic the naive tissue microenvironment. However, the efficacy of cells generated from the 3D spheroid culture system has not yet been elucidated. In the present study, we demonstrate the changes in superoxide dismutase 2 (SOD2) gene expression, an indicator of oxidative stress, on 3D spheroid MSCs. Moreover, siRNA transfection and neutralizing antibody investigations were performed to confirm the function of SOD2 and E-cadherin. Overall, we found that SOD2 siRNA transfection in the spheroid form of MSCs increases the expression of apoptotic genes and decreases the clearance of mitochondrial reactive oxygen species (ROS). As a result, we confirm that 3D spheroid formation increases E-cadherin and SOD2 expression, ultimately regulating the phosphoinositide 3-kinase (PI3K/pAkt/pNrf2 and pERK/pNrf2 signaling pathway. Additionally, we show that SOD2 expression on 3D spheroid MSCs affects the regeneration rates of destructive cartilage in an osteoarthritic model. We postulate that the impact of SOD2 expression on 3D spheroid MSCs reduces oxidative stress and apoptosis, and also promotes cartilage regeneration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/antiox9010066DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7023074PMC
January 2020

Fate Determination of ZnO in Commercial Foods and Human Intestinal Cells.

Int J Mol Sci 2020 Jan 9;21(2). Epub 2020 Jan 9.

Division of Applied Food System, Major of Food Science & Technology, Seoul Women's University, Seoul 01797, Korea.

(1) Background: Zinc oxide (ZnO) particles are widely used as zinc (Zn) fortifiers, because Zn is essential for various cellular functions. Nanotechnology developments may lead to production of nano-sized ZnO, although nanoparticles (NPs) are not intended to be used as food additives. Current regulations do not specify the size distribution of NPs. Moreover, ZnO is easily dissolved into Zn ions under acidic conditions. However, the fate of ZnO in commercial foods or during intestinal transit is still poorly understood. (2) Methods: We established surfactant-based cloud point extraction (CPE) for ZnO NP detection as intact particle forms using pristine ZnO-NP-spiked powdered or liquid foods. The fate determination and dissolution characterization of ZnO were carried out in commercial foods and human intestinal cells using in vitro intestinal transport and ex vivo small intestine absorption models. (3) Results: The results demonstrated that the CPE can effectively separate ZnO particles and Zn ions in food matrices and cells. The major fate of ZnO in powdered foods was in particle form, in contrast to its ionic fate in liquid beverages. The fate of ZnO was closely related to the extent of its dissolution in food or biomatrices. ZnO NPs were internalized into cells in both particle and ion form, but dissolved into ions with time, probably forming a Zn-ligand complex. ZnO was transported through intestinal barriers and absorbed in the small intestine primarily as Zn ions, but a small amount of ZnO was absorbed as particles. (4) Conclusion: The fate of ZnO is highly dependent on food matrix type, showing particle and ionic fates in powdered foods and liquid beverages, respectively. The major intracellular and intestinal absorption fates of ZnO NPs were Zn ions, but a small portion of ZnO particle fate was also observed after intestinal transit. These findings suggest that the toxicity of ZnO is mainly related to the Zn ion, but potential toxicity resulting from ZnO particles cannot be completely excluded.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms21020433DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7014048PMC
January 2020

Hydrothermal Treatment Enhances Antioxidant Activity and Intestinal Absorption of Rutin in Tartary Buckwheat Flour Extracts.

Foods 2019 Dec 20;9(1). Epub 2019 Dec 20.

Division of Applied Food System, Major of Food Science & Technology, Seoul Women's University, Seoul 01797, Korea.

Tartary buckwheat () is widely used in the food industry due to its functionality, which is related to its high rutin content. However, rutin is easily converted into quercetin by an endogenous enzyme during processing, resulting in a bitter taste. In this study, rutin-enriched Tartary buckwheat flour extracts (TBFEs) were obtained by hydrothermal treatments (autoclaving, boiling, and steaming), and their antioxidant activity was evaluated in human intestinal cells. The intestinal absorption of the hydrothermally treated TBFEs was also investigated using in vitro models of intestinal barriers and an ex vivo model of intestinal absorption. The results demonstrated that all of the hydrothermally treated TBFEs had increased rutin, total polyphenol, and total flavonoid contents, which enhance the in vitro and intracellular radical scavenging activities. Antioxidant enzyme activity, cellular uptake efficiency, in vitro intestinal transport efficacy, and ex vivo intestinal absorption of the hydrothermally treated TBFEs were also enhanced compared with those of native TBFE or standard rutin. These findings suggest the promising potential of hydrothermally treated TBFEs for a wide range of applications in the functional food industry.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/foods9010008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7022688PMC
December 2019

Decorin Secreted by Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Induces Macrophage Polarization via CD44 to Repair Hyperoxic Lung Injury.

Int J Mol Sci 2019 Sep 27;20(19). Epub 2019 Sep 27.

Biomedical Research Institute, MEDIPOST Co., Ltd., Seongnam 13494, Korea.

Bronchopulmonary dysplasia (BPD), caused by hyperoxia in newborns and infants, results in lung damage and abnormal pulmonary function. However, the current treatments for BPD are steroidal and pharmacological therapies, which cause neurodevelopmental impairment. Treatment with umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) is an efficient alternative approach. To prevent pulmonary inflammation in BPD, this study investigated the hypothesis that a key regulator was secreted by MSCs to polarize inflammatory macrophages into anti-inflammatory macrophages at inflammation sites. Lipopolysaccharide-induced macrophages co-cultured with MSCs secreted low levels of the inflammatory cytokines, IL-8 and IL-6, but high levels of the anti-inflammatory cytokine, IL-10. Silencing decorin in MSCs suppressed the expression of CD44, which mediates anti-inflammatory activity in macrophages. The effects of MSCs were examined in a rat model of hyperoxic lung damage. Macrophage polarization differed depending on the levels of decorin secreted by MSCs. Moreover, intratracheal injection of decorin-silenced MSCs or MSCs secreting low levels of decorin confirmed impaired alveolarization of damaged lung tissues by down-regulation of decorin. In tissues, a decrease in the anti-inflammatory macrophage marker, CD163, was observed via CD44. Thus, we identified decorin as a key paracrine factor, inducing macrophage polarization via CD44, a master immunoregulator in mesenchymal stem cells.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms20194815DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6801980PMC
September 2019

Food Additive Titanium Dioxide and Its Fate in Commercial Foods.

Nanomaterials (Basel) 2019 Aug 16;9(8). Epub 2019 Aug 16.

Division of Applied Food System, Major of Food Science & Technology, Seoul Women's University, Seoul 01797, Korea.

Titanium dioxide (TiO) is one of the most extensively utilized food additives (E171) in the food industry. Along with nanotechnology development, the concern about the presence of nanostructured particles in E171 TiO and commercial food products is growing. In the present study, the physicochemical properties of commercially available E171 TiO particles, including particle size distribution, were investigated, followed by their cytotoxicity and intestinal transport evaluation. The fate determination and quantification of E171 TiO in commercial foods were carried out based on the analytical procedure developed using simulated foods. The results demonstrated that TiO is a material mainly composed of particles larger than 100 nm, but present as an agglomerated or aggregated particle in commercial foods with amounts of less than 1% (wt/wt). Titanium dioxide particles generated reactive oxygen species and inhibited long-term colony formation, but the cytotoxicity was not related to particle size distribution or particle type (food- or general-grade). All TiO particles were mainly transported by microfold (M) cells, but also by intestinal tight junction. These findings will be useful for TiO application in the food industry and predicting its potential toxicity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/nano9081175DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6724087PMC
August 2019

Mesenchymal stem cells prevent the progression of diabetic nephropathy by improving mitochondrial function in tubular epithelial cells.

Exp Mol Med 2019 07 9;51(7):1-14. Epub 2019 Jul 9.

Department of Internal Medicine, University of Ulsan College of Medicine, Seoul, Korea.

The administration of mesenchymal stem cells (MSCs) was shown to attenuate overt as well as early diabetic nephropathy in rodents, but the underlying mechanism of this beneficial effect is largely unknown. Inflammation and mitochondrial dysfunction are major pathogenic factors in diabetic nephropathy. In this study, we found that the repeated administration of MSCs prevents albuminuria and injury to tubular epithelial cells (TECs), an important element in the progression of diabetic nephropathy, by improving mitochondrial function. The expression of M1 macrophage markers was significantly increased in diabetic kidneys compared with that in control kidneys. Interestingly, the expression of arginase-1 (Arg1), an important M2 macrophage marker, was reduced in diabetic kidneys and increased by MSC treatment. In cultured TECs, conditioned media from lipopolysaccharide-activated macrophages reduced peroxisomal proliferator-activated receptor gamma coactivator 1α (Pgc1a) expression and impaired mitochondrial function. The coculture of macrophages with MSCs increased and decreased the expression of Arg1 and M1 markers, respectively. Treatment with conditioned media from cocultured macrophages prevented activated macrophage-induced mitochondrial dysfunction in TECs. In the absence of MSC coculture, Arg1 overexpression in macrophages reversed Pgc1a suppression in TECs. These observations suggest that MSCs prevent the progression of diabetic nephropathy by reversing mitochondrial dysfunction in TECs via the induction of Arg1 in macrophages.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s12276-019-0268-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6802630PMC
July 2019

Alpha-Hederin Nanopore for Single Nucleotide Discrimination.

ACS Nano 2019 02 23;13(2):1719-1727. Epub 2019 Jan 23.

Graduate School of Biotechnology and Department of Food Science and Biotechnology , Kyung Hee University , Yongin 17104 , Republic of Korea.

Various types of biological and synthetic nanopores have been developed and utilized for the high-throughput investigation of individual biomolecules. Biological nanopores made with channel proteins are so far superior to solid-state ones in terms of sensitivity and reproducibility. However, the performance of a biological nanopore is dependent on the protein in the channel structure its dimensions are predetermined and are difficult to modify for broader applications. Here inspired by the cytotoxic mechanisms of a saponin derivative, alpha-hederin, we report a nonproteinaceous nanopore that can be formed spontaneously in a lipid membrane. We propose the pore-forming mechanism of alpha-hederin in a cholesterol-rich lipid membrane and a strategy to control the pore-forming rate by a lipid partitioning method. The small diameter and effective thickness of alpha-hederin nanopores enabled us to discriminate ssDNA homopolymers as well as four types of nucleotides, showing its potential as a DNA sequencing tool.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsnano.8b07797DOI Listing
February 2019

Protein Food Matrix⁻ZnO Nanoparticle Interactions Affect Protein Conformation, but May not Be Biological Responses.

Int J Mol Sci 2018 Dec 7;19(12). Epub 2018 Dec 7.

Major of Food Science & Technology, Division of Applied Food System, Seoul Women's University, Seoul 01797, Korea.

Because of their nutritional value, zinc oxide (ZnO) nanoparticles (NPs) are applied as a dietary source of zinc, by direct addition to complex, multiple-component food matrices. The thereby occurring interactions of NPs with food matrices may have biological or toxic effects. In particular, NP interactions with food protein can lead to structural deformation of the latter, potentially changing its digestive efficiency and gastrointestinal absorption. In this study, interactions between ZnO NPs and a representative complex protein food matrix, skim milk, were compared with those between NPs and individual components of this food matrix (i.e., protein, saccharide, and mineral). The effects of the interactions on biological responses were investigated in terms of cytotoxicity, cellular uptake, intestinal transport, structural deformation for proteins, and digestive efficiency. The results demonstrated that the physicochemical properties of ZnO NPs were strongly influenced by the protein matrix type, leading to an increased dispersion stability in the complex protein matrix. However, these interactions did not affect cell proliferation, membrane damage, cellular uptake, intestinal transportation, or protein digestive efficiency, although a slight conformational change of proteins was observed in the presence of ZnO NPs. In conclusion, no toxic effects were observed, suggesting the safety of NPs when added to complex food matrices.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms19123926DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6321177PMC
December 2018
-->