Publications by authors named "Sameh S Ali"

61 Publications

Plastic wastes biodegradation: Mechanisms, challenges and future prospects.

Sci Total Environ 2021 Aug 19;780:146590. Epub 2021 Mar 19.

Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China. Electronic address:

The growing accumulation of plastic wastes is one of the main environmental challenges currently faced by modern societies. These wastes are considered a serious global problem because of their effects on all forms of life. There is thus an urgent need to demonstrate effective eco-environmental techniques to overcome the hazardous environmental impacts of traditional disposal paths. However, our current knowledge on the prevailing mechanisms and the efficacy of synthetic plastics' biodegradation still appears limited. Under this scope, our review aims to comprehensively highlight the role of microbes, with special emphasis on algae, on the entire plastic biodegradation process focusing on the depolarization of various synthetic plastic types. Moreover, our review emphasizes on the ability of insects' gut microbial consortium to degrade synthetic plastic wastes. In this view, we discuss the schematic pathway of the biodegradation process of six types of synthetic plastics. These findings may contribute to establishing bio-upcycling processes of plastic wastes towards biosynthesis of valuable metabolic products. Finally, we discuss the challenges and opportunities for microbial valorization of degraded plastic wastes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.scitotenv.2021.146590DOI Listing
August 2021

UPLC-PDA-ESI/MS metabolic profiling of dill shoots bioactive fraction; evidence of its antioxidant and hepatoprotective effects in vitro and in vivo.

J Food Biochem 2021 Jun 26;45(6):e13741. Epub 2021 Apr 26.

Pharmacognosy Department, Faculty of Pharmacy, Cairo University, Cairo, Egypt.

Hydroxyl radical ( OH) scavenging capacity of aqueous dill (Anethum graveolens L.) shoot (ADSh) extract was assessed using electron paramagnetic resonance (EPR) spectroscopy. ADSh extract (at concentrations of 0.5 and 10 mg/ml) exerted high (OH) radical scavenging power. ADSh extract was further fractionated on Diaion HP-20 column to yield five fractions. EPR spin-trapping assay revealed fraction 4 (eluted with 75% aq. MeOH) to possess ( OH) radical scavenging capacity over a concentration range (0.01-10 mg/ml), whereas fraction 2 (eluted with 25% aq. MeOH) appeared to be pro-oxidant at concentration 0.01 mg/ml. UPLC-PDA-ESI-MS metabolite profiling of ADSh extract revealed 87 metabolites, of which 64 compounds were identified in fraction 4, the most active fraction. Furthermore, ADSh extract demonstrated a hepatoprotective effect against acetaminophen (APAP)-induced hepatotoxicity in rats. Pretreatment of rats with ADSh extract (200 mg/kg b.wt) markedly attenuated the increased in the serum hepatic enzyme levels. It also increased free glutathione level and total antioxidant capacity in the serum of treated rats. [Correction added on May 3, 2021, after first online publication: "rates" has been changed to "rats" in the previous sentence.] Additionally, levels of (TNF-α and IL-1β) were back to almost normal levels compared to the control group. The above findings suggest that ADSh extract has a protective effect against APAP-induced liver damage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jfbc.13741DOI Listing
June 2021

Efficacy of metal oxide nanoparticles as novel antimicrobial agents against multi-drug and multi-virulent Staphylococcus aureus isolates from retail raw chicken meat and giblets.

Int J Food Microbiol 2021 Apr 24;344:109116. Epub 2021 Feb 24.

Botany Department, Faculty of Science, Tanta University, Tanta 31527, Egypt; Department of Biology, College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia.

Staphylococcus aureus is among the most common zoonotic pathogens originating from animals consumed as food, especially raw chicken meat (RCM). As far as we know, this might be the first report that explores the efficacy of metal oxide nanoparticles (MONPs), such as zinc peroxide nanoparticles (ZnO-NPs), zinc oxide nanoparticles (ZnO-NPs), and titanium dioxide nanoparticles (TiO-NPs) against multidrug resistant (MDR) and/or pandrug resistant (PDR) S. aureus strains with a strong biofilm-producing ability isolated from RCM and giblets. The overall prevalence of coagulase-positive staphylococci was 21%, with a contamination level range between 10 and 10 CFU/g. The incidence of virulence genes See (21/36), pvl (16/36), clfA (15/36), sec (12/36), tst (12/36), and sea (11/36) among S. aureus strains were relatively higher those of seb, sed, fnbA, and fnbB. For antimicrobial resistance gene distribution, most strains harbored the blaZ gene (25/36), aacA-aphD gene (24/36), mecA gene (22/36), vanA gene (20/36), and apmA gene (20/36) confirmed the prevalence of MDR among S. aureus of RCM products. However, cfr (11/36), spc (9/36), and aadE (7/36) showed a relatively lower existence. The data of antibiogram resistance profiles was noticeably heterogeneous (25 patterns) with 32 MDR and four PDR S. aureus strains. All tested strains had a very high MAR index value (>0.2) except the P11 pattern (GEN, MXF, PMB), which showed a MAR index of 0.19. Among the strong biofilm-producing ability (BPA), 14 (70%) strains were isolated from wet markets, while only six strong BPA strains were isolated from supermarkets. The mean values of BPA ranged from 2.613 ± 0.04 to 11.013 ± 0.05. Clearly, ZnO-NPs show significant inhibitory activity against S. aureus strains compared with those produced by the action of ZnO-NPs and TiO-NPs. The results of anti-inflammatory activity suggest ZnO-NPs as a lead compound for designing an alternative antimicrobial agent against drug-resistant and strong biofilm-producing S. aureus isolates from retail RCM and giblets.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijfoodmicro.2021.109116DOI Listing
April 2021

Corrigendum to "Enhanced anaerobic digestion performance by two artificially constructed microbial consortia capable of woody biomass degradation and chlorophenols detoxification" [J. Hazard. Mater 389 (2020) 122076].

J Hazard Mater 2021 Mar 24;405:124326. Epub 2020 Oct 24.

Botany Department, Faculty of Science, Tanta University, Tanta 31527, Egypt; Department of Biology, College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jhazmat.2020.124326DOI Listing
March 2021

Autism spectrum disorder (ASD)-associated mitochondrial deficits are revealed in children's platelets but unimproved by hyperbaric oxygen therapy.

Free Radic Res 2021 Jan 6:1-15. Epub 2021 Jan 6.

Center for Aging and Associated Diseases, Helmy Institute of Medical Sciences, Zewail City of Science and Technology, Giza, Egypt.

Mitochondrial and immune dysfunctions are often implicated in the aetiology of autism spectrum disorder (ASD). Here, we studied for the first time the relationship between ASD severity measures and mitochondrial respiratory rates in freshly isolated platelets as well as the activity of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) in isolated neutrophils. We also verified the impact of hyperbaric oxygen therapy (HBOT) on mitochondrial and immune functions as well as on ASD severity measures. Blood samples were collected from three age-matched male groups (Control (Norm-N), autistic (Aut-N), and autistic + HBOT (Aut-H); =10 per group). Using high resolution respirometry, we found that routine basal respiration, complex I- and complex I + II-dependent oxidative phosphorylation rate were significantly impaired in Aut-N platelets. Similarly, deficits in immune response of neutrophils were evidenced through lower rates of oxygen consumption and reactive oxygen species (ROS) production by phagocytic NOX. ASD-related behavioural outcomes were found to moderately correlate with platelets' mitochondrial bioenergetic parameters as well as with NOX-mediated activity in neutrophils. HBOT was not able to improve mitochondrial dysfunctions or to counteract ASD-related behavioral deficits. Although HBOT improved one measure of the immune response; namely, NOX-mediated superoxide burst, this was not associated with significant changes in trends of recurrent infections between groups. Taken together, our data suggest that ASD-associated mitochondria and immune deficits are detectable in platelets and neutrophils. We also found no evidence that HBOT confers any significant improvement of ASD-associated physiological or behavioural phenotypes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/10715762.2020.1856376DOI Listing
January 2021

Corrigendum to "Construction of novel microbial consortia CS-5 and BC-4 valued for the degradation of catalpa sawdust and chlorophenols simultaneously with enhancing methane production" [Bioresource Technol. 301(2020), 122720].

Bioresour Technol 2021 Jan 6;320(Pt A):124355. Epub 2020 Nov 6.

Botany Department, Faculty of Science, Tanta University, Tanta 31527, Egypt; Department of Biology, College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.biortech.2020.124355DOI Listing
January 2021

Corrigendum: Acidic Alkaline Bacterial Degradation of Lignin Through Engineered Strain BL21(Lacc): Exploring the Differences in Chemical Structure, Morphology, and Degradation Products.

Front Bioeng Biotechnol 2020 11;8:868. Epub 2020 Aug 11.

Biofuels Institute, School of Environmental Science and Safety Engineering, Jiangsu University, Zhenjiang, China.

[This corrects the article DOI: 10.3389/fbioe.2020.00671.].
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fbioe.2020.00868DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7433319PMC
August 2020

Acidic Alkaline Bacterial Degradation of Lignin Through Engineered Strain BL21(Lacc): Exploring the Differences in Chemical Structure, Morphology, and Degradation Products.

Front Bioeng Biotechnol 2020 30;8:671. Epub 2020 Jun 30.

Biofuels Institute, School of Environmental Science and Safety Engineering, Jiangsu University, Zhenjiang, China.

There is increasing interest in research on lignin biodegradation compounds as potential building blocks in applications related to renewable products. More attention is necessary to evaluate the effects of the initial pH conditions during the bacterial degradation of lignin. In this study we performed experiments on lignin biodegradation under acidic and mild alkaline conditions. For acidic biodegradation, lignin was chemically pretreated with hydrogen peroxide. Alkaline biodegradation was achieved by developing the bacterial growth on Luria and Bertani medium with alkali lignin as the sole carbon source. The mutant strain BL21(Lacc) was used to carry out lignin biodegradation over 10 days of incubation. Results demonstrated that under acidic conditions there was a predominance of aliphatic compounds of the C-C type. Alkaline biodegradation was produced in the context of oxidative stress, with a greater abundance of aryl compounds. The final pH values of acidic and alkaline biodegradation of lignin were 2.53 and 7.90, respectively. The results of the gas chromatography mass spectrometry analysis detected compounds such as crotonic acid, lactic acid and 3-hydroxybutanoic acid for acidic conditions, with potential applications for adhesives and polymer precursors. Under alkaline conditions, detected compounds included 2-phenylethanol and dehydroabietic acid, with potential applications for perfumery and anti tumor/anti-inflammatory medications. Size-exclusion chromatography analysis showed that the weight-average molecular weight of the alkaline biodegraded lignin increased by 6.75-fold compared to the acidic method, resulting in a repolymerization of its molecular structure. Lignin repolymerization coincided with an increase in the relative abundance of dehydroabietic acid and isovanillyl alcohol, from 2.70 and 3.96% on day zero to 13.43 and 10.26% on 10th day. The results of the Fourier-transformed Infrared spectroscopy detected the presence of C = O bond and OH functional group associated with carboxylic acids in the acidic method. In the alkaline method there was a greater preponderance of signals related to skeletal aromatic structures, the amine functional group and the C - O - bond. Lignin biodegradation products from BL21(Laccase), under different initial pH conditions, demonstrated a promising potential to enlarge the spectrum of renewable products for biorefinery activities.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fbioe.2020.00671DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7344149PMC
June 2020

Anti-inflammatory and antioxidant effects of Apium graveolens L. extracts mitigate against fatal acetaminophen-induced acute liver toxicity.

J Food Biochem 2020 Jul 26:e13399. Epub 2020 Jul 26.

Pharmacognosy Department, Faculty of Pharmacy, Cairo University, Cairo, Egypt.

In the present work, antioxidant activity, total phenolics (TP), and total flavonoids (TF) contents of aqueous and methanol extracts of celery were determined, in addition to untargeted metabolites profiling its methanol celery root extract (MCRE) via UPLC-MS. Although MCRE exhibited the lowest TPC and TFC levels, it presented the most potential hydroxyl radical quenching effect using electron paramagnetic resonance spin trapping technique. Treatment of Acetaminophen-induced hepatotoxicity (AAH) rats with MCRE lowered serum levels of AST, ALT, ALP, TNF-α, and IL-1β significantly. Additionally, MCRE significantly increased total antioxidant capacity (TAC) and glutathione (GSH) levels relative to AAH rats. Strikingly, Kaplan-Meier survival analysis of all groups revealed a 100% prevention of acetaminophen-induced mortality of rats by MCRE pretreatment (100 mg/kg/day). MCRE prevented AAH-associated severe weight loss and elicited normal behavior in the rescued rats. Our results suggest that pretreatment with MCRE can mitigate against overdosed acetaminophen-induced acute liver failure and warrant further investigations on the potential of postinjury intervention. PRACTICAL APPLICATIONS: Acetaminophen-induced hepatotoxicity (AAH) accounts for alerting numbers of overdose-related acute liver failure and liver transplant cases with increased morbidity and mortality rates. Currently proposed mechanisms implicate mitochondria-mediated oxidative stress and inflammation in the pathogenesis of AAH, which underline current interventions employing antioxidants to combat liver damage by over-dosed acetaminophen. The present work uncovers potent protective effects of some celery extracts (and their fractions) against acetaminophen-induced oxidative stress and inflammation. Treatment of rats with fatal liver injury with methanol extract of celery root significantly reduced secretion of liver enzymes and markedly decreased inflammatory as well as oxidative stress markers in these animals. This, in turn, rescued challenged rats exposed to fatal doses of acetaminophen completely, which establishes methanol extracts of celery roots as effective therapeutic intervention against AAH. The antioxidant capacity of the extracts was determined using EPR technique, and the secondary metabolites related to antioxidant activity were characterized via UPLC-MS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/jfbc.13399DOI Listing
July 2020

Ecofriendly biodegradation of Reactive Black 5 by newly isolated Sterigmatomyces halophilus SSA1575, valued for textile azo dye wastewater processing and detoxification.

Sci Rep 2020 07 23;10(1):12370. Epub 2020 Jul 23.

Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Xuefu Rd. 301, Zhenjiang, 212013, China.

A total of seven yeast strains from 18 xylanolytic and/or xylose-fermenting yeast species isolated from the wood-feeding termite Reticulitermes chinenesis could efficiently decolorize various azo dyes under high-salt conditions. Of these strains, a novel and unique azo-degrading and halotolerant yeast, Sterigmatomyces halophilus SSA1575, has been investigated in this study. This strain could significantly decolorize four combinations of a mixture of dyes. It showed a high capability for decolorizing Reactive Black 5 (RB5) even at 1,500 mg L. The strain SSA1575 still showed a high capability for decolorizing a 50 mg L RB5 with a salt mixing at a NaCl concentration of up to 80 g L. It also exhibited significant ability to decolorize repeated additions of dye aliquots, with a reduction in time of up to 18 h. Most of the tested carbon and nitrogen sources could significantly enhance a RB5 decolorization. However, this process was inhibited by the addition of sucrose and sodium nitrate. NADH-dichlorophenol indophenol (NADH-DCIP) reductase and lignin peroxidase were determined as the key reductase and oxidase of S. halophilus SSA1575. Finally, strain SSA1575, can effectively detoxify RB5 into non-toxic products. Overall, S. halophilus SSA1575, might be a promising halotolerant yeast valued for the treatment of various textile effluents with high salinity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-020-69304-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7378048PMC
July 2020

ATR-IR and EPR spectroscopy for following the membrane restoration of isolated cortical synaptosomes in aluminium-induced Alzheimer's disease - Like rat model.

Chem Phys Lipids 2020 09 30;231:104931. Epub 2020 Jun 30.

Center for Aging and Associated Diseases, Helmy Institute of Medical Sciences, Zewail City of Science and Technology, Giza, Egypt; Children's Cancer Hospital 57357, Cair, Egypt. Electronic address:

Synaptosomal membrane peroxidation and alteration in its biophysical properties are associated with Aluminium (Al) toxicity that may lead to cognitive dysfunction and Alzheimer's disease (AD) like pathogenesis. Here we investigated the therapeutic potential of Lepedium sativum (LS) as a natural anti-inflammatory, antioxidant and as acetyl cholinesterase inhibitor in treating Al induced AD-like in rat model. We utilized ATR-IR spectroscopy to follow the restoration in the damaged membrane structure of isolated rat cortical synaptosomes and its biophysical properties, electron paramagnetic resonance (EPR) spin trapping to follow NADPH oxidase activity (NOX), and EPR spin labelling in response to LS treatment after Al intoxication. We measured the concentration of Ca ions in rat cortical tissue by inductively coupled plasma (ICP), the brain atrophy/curing and hydrocephalus by magnetic resonance imaging (MRI) besides light microscope histopathology. Our results revealed significant increase in synaptosomal membrane rgidification, order, lipid packing, reactive oxygen species (ROS) production and Ca ion concentration as a result of Al intoxication. The dramatic increase in Ca ion concentration detected in AD group associated with the increase in synaptic membrane polarity and EPR-detected order S-parameter suggest that release of synaptic vesicles into synaptic cleft might be hindered. LS treatment reversed these changes in synaptic membranes, and rescued an observed deficit in the exploratory behaviour of AD group. Our results also strongly suggest that the synaptosomal membrane phospholipids that underwent free radical attacks mediated by AlCl3, due to greater NOX activity, was prevented in the LS group. The results of ATR-IR and EPR spectroscopic techniques recommend LS as a promising therapeutic agent against synaptic membrane alterations opening a new window for AD drug developers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chemphyslip.2020.104931DOI Listing
September 2020

A novel study on the inhibitory effect of marine macroalgal extracts on hyphal growth and biofilm formation of candidemia isolates.

Sci Rep 2020 06 9;10(1):9339. Epub 2020 Jun 9.

Botany Department, Faculty of Science, Tanta University, Tanta, 31527, Egypt.

Biofilm formation and hyphal growth are considered to be the most serious virulence factors of Candida species in blood causing candidemia infections, which are difficult to treat due to the spread of resistant Candida isolates to most antifungal drugs. Therefore, in this study, we investigated the effect of different types and concentrations of selected macroalgal extracts from Cladostephus spongiosus (Phaeophyta), Laurencia papillosa (Rhodophyta), and Codium arabicum (Chlorophyta) in inhibiting those virulence factors of the isolated Candida. Acetone extract of C. spongiosus (AECS) showed a stronger anticandidal activity against the selected strains than ethanol extract. Candida krusei was the highest biofilm producer among the selected isolates. AECS showed an inhibition of C. krusei biofilm formation as well as a reduction in the viability of preformed biofilms. Also, AECS reduced various sugars in the candidal exo-polysaccaride layer (EPS). Scanning electron microscopy (SEM) and light microscopic images revealed an absence of hyphae and an alteration in the morphology of biofilm cells when treated with AECS. Moreover, AECS downregulated the expression of hyphal specific genes, hyphal wall protein 1 (HWP1), Agglutinin-like protein 1 (ALS1) and fourth secreted aspartyl proteinase (SAP4), which confirmed the inhibitory effect of AECS on hyphal growth and biofilm formation. Gas chromatography-mass spectrophotometer (GC-MS) analysis of AECS showed three major compounds, which were non-existent in the ethanol extract, and might be responsible for the anticandidal activity; these revealed compounds were 4-hydroxy-4-methyl-2-pentanone, n-hexadecenoic acid, and phenol, 2-methoxy-4-(2-propenyl). These active compounds of AECS may be promising for future pharmaceutical applications in the treatment of candidemia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-020-66000-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7283248PMC
June 2020

Human-stimulated oocyte extract induces genetic and mitochondrial reprogramming of mesenchymal stromal cells.

PLoS One 2020 26;15(5):e0232759. Epub 2020 May 26.

Center of Excellence for Stem Cells and Regenerative Medicine, Zewail City of Science and Technology, Cairo, Egypt.

Summary: Reprogramming autologous adult cells to pluripotent cells allows for relatively safe cell replacement therapy. This can be achieved by nuclear transfer, cell fusion, or induced pluripotent stem cell technology However, the epigenetic memory of the cell is considered as a great challenge facing the complete reprograming of cells by these methods. Introducing oocyte-specific factors into differentiated cells may present a promising approach by mimicking cellular reprogramming during fertilization.

Methods: Human bone marrow mesenchymal stromal cells (hBM-MSCs) were cultured with different concentrations of human metaphase II (M II) oocyte extract (0.1, 1, 5, 10, 30 ng/μl). Reprogramming was assessed at various exposure times (1, 4, 7 days). Cells were tested for their proliferation rate, morphological changes, expression of pluripotency markers, expression of mesenchymal to epithelial transition markers, and mitochondrial rejuvenation. (mitochondrial localization, morphological changes, bioenergetics, transmembrane potential, and levels of reactive oxygen species, ROS).

Results: Treatment of human BM-MSCs with 10 ng/μl oocyte extract resulted in increased cell proliferation, which was associated with the upregulation of the pluripotency genes OCT-4, NANOG, and SOX-2 and a concomitant downregulation of mesenchymal-specific genes. MSCs exhibited small, immature round mitochondria with few swollen cristae localized proximal to the cell nucleus. This was accompanied by morphological cell changes, a metabolic shift towards oxidative phosphorylation, a high mitochondrial membrane potential, and increased ROS production.

Conclusion: These data show that treatment with 10 ng/μl human MII-phase oocyte extract induced genetic and mitochondrial reprogramming of human BM-MSCs to a more embryonic phenotype.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0232759PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7250418PMC
July 2020

Molecular characterization of virulence and drug resistance genes-producing Escherichia coli isolated from chicken meat: Metal oxide nanoparticles as novel antibacterial agents.

Microb Pathog 2020 Jun 19;143:104164. Epub 2020 Mar 19.

Botany Department, Faculty of Science, Tanta University, Tanta, 31527, Egypt.

Escherichia coli is a major global foodborne pathogen, infecting a wide range of animals and contaminating their meat products. E. coli, can lead to high morbidity and mortality with a huge economic loss especially if foodborne diseases are associated with multidrug resistant (MDR)- and multivirulent-producing pathogens. Due to the increased resistance to common antimicrobials used to treat livestock animals and human infections, the discovery of new and innovative nanomaterials are in high demand. Recently, metal oxides can be considered as effective inorganic agents with antimicrobial features. Hence, this study might be the first to evaluate the efficiency of metal oxide nanoparticles (MO-NPs) as novel antibacterial agents against MDR/multivirulent E. coli pathogens isolated from chicken meat. The occurrence of pathogenic E. coli was determined in fresh warm chicken meat parts (breast, thigh, liver and gizzard). Ninety-one of 132 (69%) chicken meat parts were Escherichia -positive with E. coli as the only species isolated. Out of identified 240 E. coli strains, 72.5% (174/240) were classified as MDR E. coli strains. Fifty-five profile patterns were obtained. From each pattern, one strain was randomly selected for further analysis of virulence and resistance genes. Extracted DNA was assessed for the presence of antibiotic resistance genes (bla, bla, bla, bla, bla, tetA, aadA, and aac(3)-IV) and virulence genes (stx1, stx2, hlyA, eaeA, aggR, eltB, estIb, papA, afa and hlyD). Clustering analyses revealed that 10 E. coli harboring the highest number of virulence and resistance genes were shifted together into one cluster designated as cluster X. The average activities of zinc peroxide nanoparticles (ZnO-NPs) were higher than that of zinc oxide nanoparticles (ZnO-NPs) and titanium dioxide nanoparticles (TiO-NPs) by 20% and 29%, respectively. The anti-inflammatory activity of ZnO-NPs in comparison with aspirin was assessed using membrane stabilization, albumin denaturation, and proteinase inhibition methods. Significant anti-inflammatory activity of ZnO-NPs was achieved at concentration levels of 500-1000 μg/ml. It seems that MO-NPs are effective alternative agents, since they exhibited a competitive antibacterial capability against MDR/multivirulent-producing E. coli pathogens isolated from chicken meat. Hence, ZnO-NPs are a promising nanoparticles-based material for controlling foodborne pathogens, thereby valued for food safety applications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.micpath.2020.104164DOI Listing
June 2020

Enhanced anaerobic digestion performance by two artificially constructed microbial consortia capable of woody biomass degradation and chlorophenols detoxification.

J Hazard Mater 2020 05 22;389:122076. Epub 2020 Jan 22.

Botany Department, Faculty of Science, Tanta University, Tanta, 31527, Egypt; Biology Department, Faculty of Science, Taif University, Saudi Arabia.

Catalpa sawdust (CSW) is a promising biomass-based biofuel. However, the complex lignocellulosic structure limits its efficient utilization in biorefinery applications. It is even more so when chlorophenols (CPs), highly toxic organic substances widely used as wood preservatives, are present. Hence, it is crucial to develop effective and eco-friendly approaches to attain deconstruction of lignocellulose and chlorophenols simultaneously as well as to improve methane (CH) production efficiently. This study might be the first to explore the performance of the novel constructed microbial consortia CS-5 and BC-4 on woody biomass degradation and CPs detoxification simultaneously with CH production. After the degradation of CSW and CPs for 15 days by C5-5 or BC-4, significant reduction in lignocellulosic components and CPs mixture was realized with a total weight loss of 69.2 and 56.3 % and CPs degradation of 89 and 95 %, respectively. The toxicity of individual or mixed CPs after 15 days of degradation was reduced by approximately 90 %. The synergistic action of CS-5 and BC-4 enhanced biogas and CH yields over 76 and 64 % respectively, higher than control. Furthermore, CH production increased by 113.7 % at the peak phase of AD process. Methanosataceae represented 45.1 % of the methanogenic Archaea in digester G-III.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jhazmat.2020.122076DOI Listing
May 2020

Roem. & Schult.: A new bioactive antimicrobial and antioxidant agent to combat multi-drug/pan-drug resistant pathogens of wound burn infections.

J Tradit Complement Med 2020 Jan 12;10(1):13-25. Epub 2019 Jan 12.

Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China.

The Multidrug Drug Resistance (MDR) and Pan-Drug Resistance (PDR) remain an intractable challenge issue in public health, worldwide. Plant extracts-based biological macromolecules containing a diverse array of secondary metabolites could be potentially used as alternative approaches to control or limit MDR/PDR infections. Plants of the Solanaceae family exhibit a wide variety of secondary metabolites with antioxidant and antimicrobial properties, which render them a significant role in food and pharmaceutical applications. To our knowledge, this is the first report on phytochemical constituents, antioxidant, antimicrobial activities and toxicological safety of leaf extracts. Results revealed that phenolics and flavonoids were found to be the most abundant compounds in all extracts. Antioxidant activity of extracts was measured using DPPH and ABTS assays and the methanol extract displayed superior scavenging activity (IC = 0.06 and 0.007 mg/mL for DPPH and ABTS, respectively). Results of the GC-MS analysis revealed the identity of 10 compounds. Moreover, toxicological assessment can confirm the safety of for use. Overall, leaves are a promising natural source for the development of novel antimicrobial and antioxidant agents that could potentially combat clinical MDR/PDR pathogens.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jtcme.2019.01.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6957848PMC
January 2020

Construction of novel microbial consortia CS-5 and BC-4 valued for the degradation of catalpa sawdust and chlorophenols simultaneously with enhancing methane production.

Bioresour Technol 2020 Apr 2;301:122720. Epub 2020 Jan 2.

Botany Department, Faculty of Science, Tanta University, Tanta 31527, Egypt; Biology Department, Faculty of Science, Taif University, Saudi Arabia.

This study might be the first to explore the novel constructed microbial consortia CS-5 and BC-4 for enhancing methane (CH) production during anaerobic digestion (AD) with simultaneous degradation of catalpa sawdust and chlorophenols (CPs). Significant reduction in cellulose, hemicellulose and lignin contents was achieved after the biodegradation of catalpa sawdust for 15 days by CS-5 and BC-4, with a total weight loss of 69.2 and 56.3%, respectively. The synergistic microbial consortia enhanced cumulative biogas and CH yields by 76.3 and 64.3%, respectively higher than the corresponding control at the end of AD. More than 90% of CH was produced within 18 days of AD as a result of microbial pretreatment of catalpa sawdust. These consortia resulted in remarkably higher energy conversion efficiency of 44.3% (218.1 L CH/kg TS) over the control. CS-5 and BC-4 removed more than 69 and 77% of the total amount of CPs tested after 15 days.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.biortech.2019.122720DOI Listing
April 2020

Enzymes immobilization onto magnetic nanoparticles to improve industrial and environmental applications.

Methods Enzymol 2020 22;630:481-502. Epub 2019 Nov 22.

Botany Department, Faculty of Science, Tanta University, Tanta, Egypt.

Enzymes as specific natural biocatalysts are present in all living organisms and they play a key role in the biochemical reactions inside, as outside the cell. Despite the wide range of environmental, medical, agricultural, and food applications, the high cost, non-reusability, and limited stability of soluble (non-immobilized) enzymes are considered barriers to their commercial application. Immobilization techniques are an effective strategy for solving problems associated with free enzymes in terms of improving the efficiency and stability of catalytic enzymes, as well as enhancing their separation and reusability in continuous industrial applications. Out of different supporting materials, magnetic nanoparticles are considered as the future trend for enzyme immobilization due to their exceptional properties regarding stabilization, easy recovery and reuse. Some recent techniques of enzyme immobilization on magnetic nanoparticles will be detailed hereafter in the chapter.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/bs.mie.2019.11.006DOI Listing
December 2020

ATR-IR and EPR spectroscopy for detecting the alterations in cortical synaptosomes induced by aluminium stress.

Spectrochim Acta A Mol Biomol Spectrosc 2020 Mar 6;228:117535. Epub 2019 Nov 6.

Center for Aging and Associated Diseases, Helmy Institute of Medical Sciences, Zewail City of Science and Technology, Giza, Egypt; Children's Cancer Hospital, 57357, Cairo, Egypt. Electronic address:

Aluminium (Al) is reported to promote free radical production, decrease the antioxidant enzyme status and disturb the enzyme activity involved in acetylcholine metabolism leading to cognitive dysfunction that are strongly associated with Alzheimer's disease (AD) pathogenesis. This work aimed at investigating the effect of Al-toxicity on synaptosomal membrane biophysical properties and lipid peroxidation during 65 days. We utilized ATR-IR spectroscopy to study the changes in membrane biochemical structure and biophysical properties of isolated rat cortical synaptosomes, and EPR spin trapping and labeling to follow NADPH oxidase activity and changes of membrane order parameter, respectively. The results showed increase in membrane fluidity and disorder in early 21d of AlCl treatment, while after 42d the membrane rigidity, packing, and order increased. The late (65d) an increase in the amount of unsaturated fatty acids, the accumulation of lipid peroxide end products, and ROS production were detected in rat cortex synaptosomes mediated by Al toxicity and oxidative stress (OS). A dramatic increase was also detected in Ca level, synaptic membrane polarity, and EPR-detected order S-parameter. These outcomes strongly suggest that the synaptosomal membrane phospholipids underwent free radical attacks mediated by AlCl due to greater NOX activity, and the release of synaptic vesicles into synaptic cleft might be hindered. The adopted spectroscopic techniques have shed light on the biomolecular structure and membrane biophysical changes of isolated cortical synaptosomes for the first time, allowing researchers to move closer to a complete understanding of pathological tissues.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.saa.2019.117535DOI Listing
March 2020

Scaled-up biodiesel synthesis from Chinese Tallow Kernel oil catalyzed by Burkholderia cepacia lipase through ultrasonic assisted technology: A non-edible and alternative source of bio energy.

Ultrason Sonochem 2019 Nov 24;58:104658. Epub 2019 Jun 24.

Department of Engineering, University of Perugia, Via G. Duranti 67, 06125 Perugia, Italy.

In East Asia, for thousands of years, the fruit of Chinese tallow tree (Sapium sebiferum) has been used for multiple purposes because of its chemical composition; the presence of high amounts of lipids is remarkable, showing potential to be used as substrate for biodiesel synthesis. Previously have been reported the use of alkaline and enzymatic catalysts, microwave technology and the use of ionic liquids as co-solvents with the lipids of this tree species to produce biodiesel. This study shows the results of the use of Burkholderia cepacia lipase as enzymatic catalyst for transesterification of Chinese Tallow Kernel oil (CTK), extracted from the fruit of Chinese tallow tree, into biodiesel, with the use of ultrasonic assisted technology and without the usage of solvents. The optimal operational parameters were determined and the reactions were developed in a batch reactor with the use of ultrasonic irradiation and emulsification to enhance the mass transfer. The scaled-up experiments, in an especially designed 3 L capacity reactor, showed promising results, obtaining 55.20% biodiesel and a kinematic viscosity of 10.31 mm.s in only 4 h, in comparison with previously published (in vitro) methods. The valorization of this non-edible source of oil represents an opportunity to use as an alternative source for bioenergy and also to tackle the uncontrolled expansion of this oleaginous tree species in some ecologically fragile ecosystems.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ultsonch.2019.104658DOI Listing
November 2019

L.: Traditional herbal medicine against A and A toxin genes-producing drug resistant .

J Tradit Complement Med 2020 Jul 15;10(4):366-377. Epub 2019 May 15.

Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, China.

The Pan-Drug Resistant (PDR), remains an intractable challenge in public health worldwide and this pathogenicity is mainly due to the presence of a cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA). On the other hand, plant extracts such as contain a diverse array of secondary metabolites, which could be potentially used to combat pathogens. To our knowledge, this is the first report on the biomedical potential of extract against cytotoxin-associated genes producing PDR . In this investigation, out of 45 gastric antral biopsy specimens of dyspeptic patients, 20 strains were confirmed as Eight (40%) out of 20 strains were PDR while the rest of the strains were Multi-Drug Resistant (MDR) strains. Genotypic analyses of PDR strains showed that and genes were found to be 75% and 87.5%, respectively and was the most common subtype of gene. showed a significant higher anti- activity compared to that of and . Eugenol was the major phenolic compound (28.14%) detected in the methanolic extract of . Clearly, results of the toxicological assessment confirmed the safety of for use. Hence, these results suggest that could be a new useful natural antimicrobial agent that could potentially combat cytotoxin genes-producing drug-resistant . Moreover, these findings provide a scientific basis for the development of antimicrobial agents from traditional herbal medicines for gastroprotection against gastric ulcer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jtcme.2019.05.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7365789PMC
July 2020

Pharmaceutical Potential of a Novel Chitosan Derivative Schiff Base with Special Reference to Antibacterial, Anti-Biofilm, Antioxidant, Anti-Inflammatory, Hemocompatibility and Cytotoxic Activities.

Pharm Res 2018 Nov 7;36(1). Epub 2018 Nov 7.

Botany Department, Faculty of Science, Tanta University, Tanta, 31527, Egypt.

Purpose: Chitosan and its derivatives possess several unique properties relevant in the field of pharmaceutics and medicinal chemistry. This study aimed to evaluate the pharmaceutical performance of an innovative chitosan derivative, methyl acrylate chitosan bearing p-nitrobenzaldehyde (MA*CS*pNBA) Schiff base.

Methods: The antibacterial activity of MA*CS*pNBA was tested against multi-drug resistant (MDR) Gram-negative and Gram-positive bacteria using agar-well diffusion method. Anti-biofilm formation was analyzed using a microtitre plate. Antioxidant assays were performed to assess the scavenging activity of MA*CS*pNBA using DPPH, hydrogen peroxide, superoxide together with its reducing power activity. Anti-inflammatory activity was evaluated by albumin denaturation, membrane stabilization, and proteinase inhibition methods. MA*CS*pNBA was tested for its hemolytic efficiency on human erythrocytes. Cytotoxicity of MA*CS*pNBA was evaluated by MTT assay.

Results: MA*CS*pNBA showed a significant performance as an antibacterial candidate against MDR bacteria, anti-biofilm, antioxidant and anti-inflammatory biomaterial, evidencing hemocompatibility and no cytotoxicity. It exhibited a significant negative correlation with biofilm formation by the MDR-PA-09 strain. Biological activities were found to be significantly concentration-dependent.

Conclusions: the newly chitosan derivative MA*CS*pNBA showed to be promising for pharmaceutical applications, expanding the treatment ways toward skin burn infections since it allied excellent antibacterial, anti-biofilm, antioxidant, anti-inflammatory, hemocompatibility and absence of cytotoxic activities.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11095-018-2535-xDOI Listing
November 2018

Synthesis, characterization and biomedical applications of a novel Schiff base on methyl acrylate-functionalized chitosan bearing p-nitrobenzaldehyde groups.

Int J Biol Macromol 2019 Feb 4;122:833-843. Epub 2018 Nov 4.

Botany Department, Faculty of Science, Tanta University, Tanta 31527, Egypt.

Amino-functionalization has gained significant attention in the chemical modification of carbohydrate polymers due to their potential biomedical applications. Here, the preparation of innovative functionalized chitosan bearing amino-containing groups and equipped with p-nitrobenzaldehyde groups, resulting in an aminated chitosan bearing p-nitrobenzaldehyde (AmCs-pNBA) was described for the first time. The most important advantage of the chitosan functionalization was the success of its preparation at room temperature, avoiding the polymerization of methyl acrylate and instead it reacted entirely with chitosan. The resulting methyl acrylate chitosan was subsequently improved by the synthesized AmCs-pNBA Schiff base via the condensation of aldehyde groups with aminated chitosan. The structural characteristics of AmCs-pNBA were examined by FT-IR, XRD, TGA, SEM, and elemental analysis techniques. The antimicrobial, antioxidant, and anti-biofilm activities of AmCs-pNBA were assessed in vitro. The results revealed that this newly synthesized chitosan derivative displayed significant superior antibacterial, antioxidant, and anti-biofilm activities over the original chitosan. Besides, cytotoxicity and hemolytic analysis of the AmCs-pNBA were also evaluated. Results indicated that AmCs-pNBA support cell viability and proliferation without obvious hemolysis. These results show the potential of synthesizing the novel biomaterial candidate, AmCs-pNBA, with improved antibacterial, anti-biofilm, and antioxidant properties that may open a new perspective in biomedical applications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijbiomac.2018.11.005DOI Listing
February 2019

Corrigendum to "Resolving Contributions of Oxygen-Consuming and ROS-Generating Enzymes at the Synapse".

Oxid Med Cell Longev 2017 28;2017:1710632. Epub 2017 Dec 28.

Center for Aging and Associated Diseases, Helmy Institute of Medical Sciences, Zewail City of Science and Technology, Giza, Egypt.

[This corrects the article DOI: 10.1155/2016/1089364.].
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1155/2017/1710632DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5763140PMC
December 2017

Drug resistance profile and molecular characterization of extended spectrum beta-lactamase (ESβL)-producing Pseudomonas aeruginosa isolated from burn wound infections. Essential oils and their potential for utilization.

Microb Pathog 2018 Mar 3;116:301-312. Epub 2018 Feb 3.

Abbasia Chest Hospital, Ministry of Health, 11765 Cairo, Egypt.

Objectives: Pseudomonas aeruginosa producing extended spectrum β-lactamase (ESβL) enzyme had the ability for antimicrobial resistance mechanisms and its multidrug-resistant (MDR) phenotype, has been increasingly reported as a major clinical concern worldwide. The aim of this study was to (i) characterize ESβL-producing MDR P. aeruginosa isolated from burn wound infections phenotypically and molecularly, (ii) evaluate the antibacterial activity of some essential oils (EOs) against selected ESβL-producing drug resistant P. aeruginosa and (iii) characterize a promising EO.

Methods: Identification and antibiotic susceptibility tests were performed for all isolates. ESβL production was detected phenotypically by an initial screening test (IST) and a phenotypic confirmatory test (PCT). Additionally, ESβL-producing isolates were also characterized molecularly. The antibacterial activity was detected using a disc diffusion method. Mechanisms of antibacterial action, the fatty acid profile, and functional groups characterization of the promising EO were analyzed using scanning and transmission electron microscopy (SEM & TEM), gas chromatography-mass spectrometry (GC-MS), and Fourier transform infrared (FTIR) spectroscopy, respectively.

Results: A total of 50 non duplicated P. aeruginosa isolates from the wound samples of burn patients were identified. Of these, MDR and pan-drug resistance (PDR) showed a high prevalence in 38 (76%) isolates obtained from 10 clusters, while 21 (42%) were identified as ESβL-producing MDR or PDR P. aeruginosa isolates. Phenotypic detection of ESβL production showed that 20% were considered positive ESβL-producing P. aeruginosa using the IST, and were increased to 56% by the PCT. The most prevalent ESβL-encoding gene was bla (60.7%), followed by bla (53.6%) and bla (42.8%). Ginger oil is the most efficient antibacterial agent and its antibacterial action mechanism is attributed to the morphological changes in bacterial cells. The oil characterization revealed that 9,12-Octadecadienoic acid methyl ester is the major fatty acid (50.49%) identified.

Conclusion: The high incidence of drug-resistance in ESβL-producing P. aeruginosa isolated from burn wounds is alarming. As proven in vitro, EOs may represent promising natural alternatives against ESβL-producing PDR or MDR P. aeruginosa isolates.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.micpath.2018.02.005DOI Listing
March 2018

The diabetic brain and cognition.

J Neural Transm (Vienna) 2017 11 1;124(11):1431-1454. Epub 2017 Aug 1.

The Center for Successful Aging with Diabetes, Endocrinology Institute, Gertner Institute, Sheba Medical Center, Epidemiology D., Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.

The prevalence of both Alzheimer's disease (AD) and vascular dementia (VaD) is increasing with the aging of the population. Studies from the last several years have shown that people with diabetes have an increased risk for dementia and cognitive impairment. Therefore, the authors of this consensus review tried to elaborate on the role of diabetes, especially diabetes type 2 (T2DM) in both AD and VaD. Based on the clinical and experimental work of scientists from 18 countries participating in the International Congress on Vascular Disorders and on literature search using PUBMED, it can be concluded that T2DM is a risk factor for both, AD and VaD, based on a pathology of glucose utilization. This pathology is the consequence of a disturbance of insulin-related mechanisms leading to brain insulin resistance. Although the underlying pathological mechanisms for AD and VaD are different in many aspects, the contribution of T2DM and insulin resistant brain state (IRBS) to cerebrovascular disturbances in both disorders cannot be neglected. Therefore, early diagnosis of metabolic parameters including those relevant for T2DM is required. Moreover, it is possible that therapeutic options utilized today for diabetes treatment may also have an effect on the risk for dementia. T2DM/IRBS contribute to pathological processes in AD and VaD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00702-017-1763-2DOI Listing
November 2017

From Human Mesenchymal Stem Cells to Insulin-Producing Cells: Comparison between Bone Marrow- and Adipose Tissue-Derived Cells.

Biomed Res Int 2017 11;2017:3854232. Epub 2017 May 11.

Urology and Nephrology Center, Mansoura, Egypt.

The aim of this study is to compare human bone marrow-derived mesenchymal stem cells (BM-MSCs) and adipose tissue-derived mesenchymal stem cells (AT-MSCs), for their differentiation potentials to form insulin-producing cells. BM-MSCs were obtained during elective orthotopic surgery and AT-MSCs from fatty aspirates during elective cosmetics procedures. Following their expansion, cells were characterized by phenotyping, trilineage differentiation ability, and basal gene expression of pluripotency genes and for their metabolic characteristics. Cells were differentiated according to a Trichostatin-A based protocol. The differentiated cells were evaluated by immunocytochemistry staining for insulin and c-peptide. In addition the expression of relevant pancreatic endocrine genes was determined. The release of insulin and c-peptide in response to a glucose challenge was also quantitated. There were some differences in basal gene expression and metabolic characteristics. After differentiation the proportion of the resulting insulin-producing cells (IPCs), was comparable among both cell sources. Again, there were no differences neither in the levels of gene expression nor in the amounts of insulin and c-peptide release as a function of glucose challenge. The properties, availability, and abundance of AT-MSCs render them well-suited for applications in regenerative medicine. . BM-MSCs and AT-MSCs are comparable regarding their differential potential to form IPCs. The availability and properties of AT-MSCs render them well-suited for applications in regenerative medicine.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1155/2017/3854232DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5444016PMC
March 2018

Effective bio-pretreatment of sawdust waste with a novel microbial consortium for enhanced biomethanation.

Bioresour Technol 2017 Aug 1;238:425-432. Epub 2017 Apr 1.

Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, 212013 Zhenjiang, China. Electronic address:

Anaerobic digestion (AD) is considered an efficient cost-effective technology for sustainable biogas production from lignocellulosic wastes. A novel lignocellulosic degradation microbial consortium (LCDC) was isolated from rotten sawdust, and further used for sawdust pretreatment prior to AD. Results showed that pretreatment of sawdust for 10days led to significant reduction in cellulose, hemicelluloses, and lignin contents by 37.5%, 39.6%, and 56.7%, respectively, with respect to the control. In addition, the pretreatment enhanced cumulative biogas yield, which reached its maximum value of 312.0LkgVS after 28days of AD (25.6% higher than the corresponding control). Moreover, the maximum significant cumulative methane yield was recorded after 28days of AD of the pretreated sawdust (155.2LkgVS), which represented 72.6% higher than the corresponding control. Significantly higher biomethane yield from sawdust pretreated with LCDC confirms that this process is more economical than the previous reports.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.biortech.2017.03.187DOI Listing
August 2017

Hypoxia-inducible factor-1α activation improves renal oxygenation and mitochondrial function in early chronic kidney disease.

Am J Physiol Renal Physiol 2017 Aug 22;313(2):F282-F290. Epub 2017 Mar 22.

Division of Nephrology and Hypertension, Department of Medicine, University of California, San Diego, and VA San Diego Healthcare System, San Diego, California;

The pathophysiology of chronic kidney disease (CKD) is driven by alterations in surviving nephrons to sustain renal function with ongoing nephron loss. Oxygen supply-demand mismatch, due to hemodynamic adaptations, with resultant hypoxia, plays an important role in the pathophysiology in early CKD. We sought to investigate the underlying mechanisms of this mismatch. We utilized the subtotal nephrectomy (STN) model of CKD to investigate the alterations in renal oxygenation linked to sodium (Na) transport and mitochondrial function in the surviving nephrons. Oxygen delivery was significantly reduced in STN kidneys because of lower renal blood flow. Fractional oxygen extraction was significantly higher in STN. Tubular Na reabsorption was significantly lower per mole of oxygen consumed in STN. We hypothesized that decreased mitochondrial bioenergetic capacity may account for this and uncovered significant mitochondrial dysfunction in the early STN kidney: higher oxidative metabolism without an attendant increase in ATP levels, elevated superoxide levels, and alterations in mitochondrial morphology. We further investigated the effect of activation of hypoxia-inducible factor-1α (HIF-1α), a master regulator of cellular hypoxia response. We observed significant improvement in renal blood flow, glomerular filtration rate, and tubular Na reabsorption per mole of oxygen consumed with HIF-1α activation. Importantly, HIF-1α activation significantly lowered mitochondrial oxygen consumption and superoxide production and increased mitochondrial volume density. In conclusion, we report significant impairment of renal oxygenation and mitochondrial function at the early stages of CKD and demonstrate the beneficial role of HIF-1α activation on renal function and metabolism.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1152/ajprenal.00579.2016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5582905PMC
August 2017

Sex-specific differences in mitochondria biogenesis, morphology, respiratory function, and ROS homeostasis in young mouse heart and brain.

Physiol Rep 2017 Mar;5(6)

Center for Aging and Associated Diseases, Helmy Institute of Medical Sciences, Zewail City of Science and Technology, Giza, Egypt

Sex-specific differences in mitochondrial function and free radical homeostasis are reported in the context of aging but not well-established in pathogeneses occurring early in life. Here, we examine if sex disparity in mitochondria function, morphology, and redox status starts early and hence can be implicated in sexual dimorphism in cardiac as well as neurological disorders prevalent at young age. Although mitochondrial activity in the heart did not significantly vary between sexes, female brain exhibited enhanced respiration and higher reserve capacity. This was associated with lower HO production in female cardiac and brain tissues. Using transmission electron microscopy, we found that the number of female cardiac mitochondria is moderately greater (117 ± 3%,  = 0.049,  = 4) than male's, which increased significantly for cortical mitochondria (134 ± 4%,  = 0.001,  = 4). However, male's cardiac mitochondria exhibited fragmented, circular, and smaller mitochondria relative to female's mitochondria, while no morphologic sex-dependent differences were observed in cortical mitochondria. No sex differences were detected in Nox2 and Nox4 proteins or O-consuming/HO-producing activities in brain homogenate or synaptosomes. However, a strong trend of increased EPR-detected NOX superoxide in male synaptosomes hinted at higher superoxide dismutase activity in female brains, which was confirmed by two independent protocols. We also provide direct evidence that respiring mitochondria generally produce an order-of-magnitude lower reactive oxygen species (ROS) proportions than currently estimated. Our results indicate that sex differences in mitochondrial biogenesis, bioenergetics, and morphology may start at young age and that sex-dependent SOD capacity may be responsible for differences in ROS homeostasis in heart and brain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14814/phy2.13125DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5371549PMC
March 2017