• The Korean Journal of Physiology and Pharmacology
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• v.26 no.4
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• pp.263-275
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• 2022

There is a paucity of detailed data related to the effect of senescence on the mitochondrial antioxidant capacity and redox state of senescent human cells. Activities of TCA cycle enzymes, respiratory chain complexes, hydrogen peroxide (H₂O₂), superoxide anions (SA), lipid peroxides (LPO), protein carbonyl content (PCC), thioredoxin reductase 2 (TrxR2), superoxide dismutase 2 (SOD2), glutathione peroxidase 1 (GPx1), glutathione reductase (GR), reduced glutathione (GSH), and oxidized glutathione (GSSG), along with levels of nicotinamide cofactors and ATP content were measured in young and senescent human foreskin fibroblasts. Primary and senescent cultures were biochemically identified by monitoring the augmented cellular activities of key glycolytic enzymes including phosphofructokinase, lactate dehydrogenase, and glycogen phosphorylase, and accumulation of H₂O₂, SA, LPO, PCC, and GSSG. Citrate synthase, aconitase, α-ketoglutarate dehydrogenase, succinate dehydrogenase, malate dehydrogenase, isocitrate dehydrogenase, and complex I-III, II-III, and IV activities were significantly diminished in P25 and P35 cells compared to P5 cells. This was accompanied by significant accumulation of mitochondrial H₂O₂, SA, LPO, and PCC, along with increased transcriptional and enzymatic activities of TrxR2, SOD2, GPx1, and GR. Notably, the GSH/GSSG ratio was significantly reduced whereas NAD⁺/NADH and NADP⁺/NADPH ratios were significantly elevated. Metabolic exhaustion was also evident in senescent cells underscored by the severely diminished ATP/ADP ratio. Profound oxidative stress may contribute, at least in part, to senescence pointing at a potential protective role of antioxidants in aging-associated disease.

• Applied Microscopy
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• v.15 no.1
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• pp.13-30
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• 1985

This study was undertaken to investigate the effect of lead on organisms. Mice received 15mg or 30mg of lead acetate per kg body weight every day for 1, 2 or 3 weeks, and the livers and kidneys were removed 24h after repeated injections. The livers and kidneys were used as sources for measurement of enzyme activities and for observation of alterations in ultrastructure. It was observed that body weights of mice treated with lead acetate were decreased when compared with those before treatment. This decrease in body weight was proportional to dose. The enzyme activities of succinate and malate dehydrogenases of experimental group that was treated with lead acetate for 1 week were nearly unchanged when compared with controls, but the enzyme activities of experimental group that was treated with lead acetate for 2 or 3 weeks were lower than those of controls. Changes in the enzyme activities were dependent on, but were not proportional to dose. Histologic examination of livers and kidneys after lead treatment showed that lead compound was accumulated and damaged in nucleus and mitochondria mainly. It was also observed that intranuclear inclusion bodies were formed only in epithelial cell of kidney proximal tubule after lead treatment. The overall changes in the ultrastructure were much greater in the livers than in the kidneys. From the above results, it nay be possible to conclude that the lead results in the decrease in body weight, reduction in the succinate dehydrogenate and malate dehydrogenase activities, and damages in the ultrastructure of kidney and liver in mouse. The presence of intranuclear inclusion bodies only in the kidney implies that these bodies protect the kidney from lead toxicity to some extent.

• BMB Reports
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• v.37 no.4
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• pp.454-459
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• 2004

Experimental hyperoxia represents a suitable in vitro model to study some pathogenic mechanisms related to oxidative stress. Moreover, it allows the investigation of the molecular pathophysiology underlying oxygen therapy and toxicity. In this study, a modified experimental set up was adopted to accomplish a model of moderate hyperoxia (50% $O_2$, 96 h culture) to induce oxidative stress in the human leukemia cell line, U-937. Spectrophotometric measurements of mitochondrial respiratory enzyme activities, NMR spectroscopy of culture media, determination of antioxidant enzyme activities, and cell proliferation and differentiation assays were performed. The data showed that moderate hyperoxia in this myeloid cell line causes: i) intriguing alterations in the mitochondrial activities at the levels of succinate dehydrogenase and succinate-cytochrome c reductase; ii) induction of metabolic compensatory adaptations, with significant shift to glycolysis; iii) induction of different antioxidant enzyme activities; iv) significant cell growth inhibition and v) no significant apoptosis. This work will permit better characterization the mitochondrial damage induced by hyperoxia. In particular, the data showed a large increase in the succinate cytochrome c reductase activity, which could be a fundamental pathogenic mechanism at the basis of oxygen toxicity.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.4
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• pp.457-463
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• 2016

The goal of this work was to investigate the correlations between MyHC mRNA transcription and their corresponding protein expressions in porcine longissimus muscle (LM) during postnatal growth of pigs. Five DLY ($Duroc{\times}Landrace{\times}Yorkshire$) crossbred pigs were selected, slaughtered and sampled at postnatal 7, 30, 60, 120, and 180 days, respectively. Each muscle was subjected to quantity MyHCs protein contents through an indirect enzyme-linked immunosorbent assay (ELISA), to quantity myosin heavy-chains (MyHCs) mRNA abundances using real-time polymerase chain reaction. We calculated the proportion (%) of each MyHC to total of four MyHC for two levels, respectively. Moreover, the activities of several key energy metabolism enzymes were determined in LM. The result showed that mRNA transcription and protein expression of MyHC I, IIa, IIx and IIb in LM all presented some obvious changes with postnatal aging of pigs, especially at the early stage after birth, and their mRNA transcriptions were easy to be influenced than their protein expressions. The relative proportion of each MyHC mRNA was significantly positively related to that of its corresponding protein (p<0.01), and MyHC I mRNA proportion was positively correlated with creatine kinase (CK), succinate dehydrogenase (SDH), malate dehydrogenase (MDH) activities (p<0.05). These data suggested that MyHC mRNA transcription can be used to reflect MyHC expression, metabolism property and adaptive plasticity of porcine skeletal muscles, and MyHC mRNA composition could be a molecular index reflecting muscle fiber type characteristics.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.3
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• pp.423-432
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• 2013

Zi geese (Anser anser domestica) belong to the white geese and are excellent layers with a superior feed-to-egg conversion ratio. Quantitative gene expression analysis, such as Real-time qRT-PCR, will provide a good understanding of ovarian function during egg-laying and consequently improve egg production. However, we still don't know what reference genes in geese, which show stable expression, should be used for such quantitative analysis. In order to reveal such reference genes, the stability of seven genes were tested in five tissues of Zi geese. Methodology/Principal Findings: The relative transcription levels of genes encoding hypoxanthine guanine phosphoribosyl transferase 1 (HPRT1), ${\beta}$-actin (ACTB), ${\beta}$-tubulin (TUB), glyceraldehyde-3-phosphate-dehydrogenase (GADPH), succinate dehydrogenase flavoprotein (SDH), 28S rRNA (28S) and 18S rRNA (18S) have been quantified in heart, liver, kidney, muscle and ovary in Zi geese respectively at different developmental stages (1 d, 2, 4, 6 and 8 months). The expression stability of these genes was analyzed using geNorm, NormFinder and BestKeeper software. Conclusions: The expression of 28S in heart, GAPDH in liver and ovary, ACTB in kidney and HPRT1 in muscle are the most stable genes as identified by the three different analysis methods. Thus, these genes are recommended for use as candidate reference genes to compare mRNA transcription in various developmental stages of geese.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.1
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• pp.95-106
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• 2018

To evaluate appropriate reference genes for the normalization of quantitative reverse transcription PCR (RT-qPCR) data with embryonic and larval samples from Russian sturgeon Acipenser gueldenstaedtii, the expression stability of eight candidate housekeeping genes, including beta-actin (ACTB), elongation factor-1A (EF1A), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), histone 2A (H2A), ribosomal protein L5 (RPL5), ribosomal protein L7 (RPL7), succinate dehydrogenase (SDHA), and ubiquitin-conjugating enzyme E2 (UBE2A), were tested using embryonic samples from 12 developmental stages and larval samples from 11 ontogenic stages. Based on the stability rankings from three statistic software packages, geNorm, NormFinder, and BestKeeper, the expression stability of the embryonic subset was ranked as UBE2A>H2A>SDHA>GAPDH>RPL5>EF1A>ACTB>RPL7. On the other hand, the ranking in the larval subset was determined as UBE2A>GAPDH>SDHA>RPL5>RPL7>H2A>EF1A>AC TB. When the two subsets were combined, the overall ranking was UBE2A>SDHA>H2A>RPL5>GAPDH>EF1A>ACTB>RPL7. Taken together, our data suggest that UBE2A and SDHA are recommended as suitable references for developmental and ontogenic samples of this sturgeon species, whereas traditional housekeepers such as ACTB and GAPDH may not be suitable candidates.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.710-716
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• 2016

Gamma-aminobutyric acid (GABA) is a non-protein amino acid, which is an important inhibitor of neurotransmission in the human brain. GABA is also used as the precursor of biopolymer Nylon-4 production. In this study, the carbon flux from the tricarboxylic acid cycle was directed to the GABA shunt pathway for the production of GABA from glucose. The GABA shunt enzymes succinate-semialdehyde dehydrogenase (GabD) and GABA aminotransferase (GabT) were co-localized along with the GABA transporter (GadC) by using a synthetic scaffold complex. The co-localized enzyme scaffold complex produced 0.71 g/l of GABA from 10 g/l of glucose. Inactivation of competing metabolic pathways in mutant E. coli strains XBM1 and XBM6 increased GABA production 13% to reach 0.80 g/l GABA by the enzymes co-localized and expressed in the mutant strains. The recombinant E. coli system developed in this study demonstrated the possibility of the pathway of the GABA shunt as a novel GABA production pathway.

• Annals of Clinical Neurophysiology
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• v.19 no.1
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• pp.40-45
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• 2017

Background: Telbivudine is a nucleoside analogue used for the treatment of chronic hepatitis B, but it often develops mitochondrial toxicity leading to symptomatic myopathy. In this study, three patients with telbivudine induced myopathy were enrolled in order to investigate the nature and pathogenesis of mitochondrial toxicity caused by long-term use of telbivudine. Methods: Clinical features, laboratory findings, muscle pathology, and quantitation of mitochondrial DNA were studied in three patients. Results: Patients presented with progressive muscle weakness with high serum creatine kinase levels. Light microscopic findings of muscle pathology showed ragged red fibers that reacted strongly with succinate dehydrogenase stain, but negative for cytochrome c oxidase activities. Electron microscopy revealed abnormal mitochondrial accumulation with rod shaped inclusions. The quantitative peroxidase chain reaction showed a depletion of mitochondrial DNA in skeletal muscle of the patients. Conclusions: Nucleoside analogues including telbivudine are potent inhibitors of viral DNA polymerases. However, they are not specific for viral DNA and can disturb mitochondrial replication at the same time. All nucleotide analogues should be used with close clinical observation in order to avoid development of mitochondrial myopathy.

• Biomolecules & Therapeutics
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• v.20 no.2
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• pp.165-170
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• 2012

Cell migration plays a role in many physiological and pathological processes. Reactive oxygen species (ROS) produced in mammalian cells influence intracellular signaling processes which in turn regulate various biological activities. Here, we investigated whether melanoma cell migration could be controlled by ROS production under normoxia condition. Cell migration was measured by wound healing assay after scratching confluent monolayer of B16F10 mouse melanoma cells. Cell migration was enhanced over 12 h after scratching cells. In addition, we found that ROS production was increased by scratching cells. ERK phosphorylation was also increased by scratching cells but it was decreased by the treatment with ROS scavengers, N-acetylcysteine (NAC). Tumor cell migration was inhibited by the treatment with PD98059, ERK inhibitor, NAC or DPI, well-known ROS scavengers. Tumor cell growth as judged by succinate dehydrogenase activity was inhibited by NAC treatment. When mice were intraperitoneally administered with NAC, the intracellular ROS production was reduced in peripheral blood mononuclear cells. In addition, B16F10 tumor growth was significantly inhibited by in vivo treatment with NAC. Collectively, these findings suggest that tumor cell migration and growth could be controlled by ROS production and its downstream signaling pathways, in vitro and in vivo.

• Nutrition Research and Practice
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• v.17 no.4
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• pp.660-669
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• 2023

BACKGROUND/OBJECTIVES: To investigate the effect and regulatory mechanism of resveratrol supplementation on the mitochondrial energy metabolism of rats with exercise-induced fatigue. MATERIALS/METHODS: Forty-eight Sprague-Dawley male rats were divided randomly into a blank control group (C), resveratrol group (R), exercise group (E), and exercise and resveratrol group (ER), with 12 rats in each group. Group ER and group E performed 6-wk swimming training with 5% wt-bearing, 60 min each time, 6 days a wk. Group ER was given resveratrol 50 mg/kg by gavage one hour after exercise; group R was only given resveratrol 50 mg/kg by gavage; group C and group E were fed normally. The same volume of solvent was given by gavage every day. RESULTS: Resveratrol supplementation could reduce the plasma blood urea nitrogen content, creatine kinase activity, and malondialdehyde content in the skeletal muscle, increase the total superoxide dismutase activity in the skeletal muscle, and improve the fatigue state. Resveratrol supplementation could improve the activities of Ca²⁺-Mg²⁺-ATPase, Na⁺-K⁺-ATPase, succinate dehydrogenase, and citrate synthase in the skeletal muscle. Furthermore, resveratrol supplementation could up-regulate the sirtuin 1 (SIRT1)-proliferator-activated receptor gamma coactivator-1α (PGC-1α)-nuclear respiratory factor 1 pathway. CONCLUSIONS: Resveratrol supplementation could promote mitochondrial biosynthesis via the SIRT1/PGC-1α pathway, increase the activity of the mitochondrial energy metabolism-related enzymes, improve the antioxidant capacity of the body, and promote recovery from exercise-induced fatigue.