• Animal cells and systems
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• v.2 no.2
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• pp.259-267
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• 1998

A deletion of one out of the two copies of 9-bp repeat sequence (CCCCCTCTA), between the cytochrome oxidase II and Iysine tranfer RNA (COII/$tRNA^{Lys}$) genes in human mitochondrial DNA (mtDNA) has been used as a polymorphic anthropological marker for people of east Asian origin, and to lesser extent, Pacific and African populations. We searched for the 9-bp deletion of the intergenic COII/$tRNA^{Lys}$ Lys region in two Korean populations (175 from Seoul and 38 from Cheju) and examine the distibution of this deletion in world populations. The 9-bp deletion was detected directly by electrophoresis of the polymerase chain reaction (PCR)-amplified nucleotide(nt) 8211-8310 mtDNA fragment. The frequencies of the 9-bp deletion were significantly different between the Seoul (16%) and Cheju (8%) populations. Examination of data from the world populations suggests a geographic gradient. The frequency reaches its highest values in some Pacific island populations and decreases along the southeast Asia-Siberia transect. In spite of this geographic gradient, Mongoloid populations including Korean, Chinese, Japanese, and Mongolian populations were relatively homo-geneous with regard to the 9-bp deletion type of the intergenic COII/$tRNA^{Lys}$ region. These results indicate Koreans are genetically related to northeast Asian populations, and have a maternal mongoloid ancestry. Therefore, the 9-bp deletion of the intergenic COII/$tRNA^{Lys}$ region will provide significant information to elucidate the historical patterns of migration of the Mongoloids.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.4
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• pp.537-547
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• 2018

Objective: This study was performed to understand transcriptional changes in the genes involved in gluconeogenesis and glycolysis pathways following castration of bulls. Methods: Twenty Korean bulls were weaned at average 3 months of age, and castrated at 6 months. Liver tissues were collected from bulls (n = 10) and steers (n = 10) of Korean cattle, and hepatic gene expression levels were measured using quantitative real-time polymerase chain reaction. We examined hepatic transcription levels of genes encoding enzymes for irreversible reactions in both gluconeogenesis and glycolysis as well as genes encoding enzymes for the utilization of several glucogenic substrates. Correlations between hepatic gene expression and carcass characteristics were performed to understand their associations. Results: Castration increased the mRNA (3.6 fold; p<0.01) and protein levels (1.4 fold; p<0.05) of pyruvate carboxylase and mitochondrial phosphoenolpyruvate carboxykinase genes (1.7 fold; p<0.05). Hepatic mRNA levels of genes encoding the glycolysis enzymes were not changed by castration. Castration increased mRNA levels of both lactate dehydrogenase A (1.5 fold; p<0.05) and lactate dehydrogenase B (2.2 fold; p<0.01) genes for lactate utilization. Castration increased mRNA levels of glycerol kinase (2.7 fold; p<0.05) and glycerol-3-phosphate dehydrogenase 1 (1.5 fold; p<0.05) genes for glycerol utilization. Castration also increased mRNA levels of propionyl-CoA carboxylase beta (mitochondrial) (3.5 fold; p<0.01) and acyl-CoA synthetase short chain family member 3 (1.3 fold; p = 0.06) genes for propionate incorporation. Conclusion: Castration increases transcription levels of critical genes coding for enzymes involved in irreversible gluconeogenesis reactions from pyruvate to glucose and enzymes responsible for incorporation of glucogenic substrates including lactate, glycerol, and propionate. Hepatic gluconeogenic gene expression levels were associated with intramuscular fat deposition.

• Journal of Aquaculture
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• v.6 no.3
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• pp.221-233
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• 1993

Cell size, DNA content, chromosome and PCR-based mitochondrial 12S rRNA gene analyses were conducted to obtain basic informations for genetic stock identification of spotted flounder (Verasper variegatus) from Yeocheun, Korea. The mean erythrocytic and nuclear volumes of spotted flounder were $211.10{\mu}m^3$ and $23.03{\mu}m^3$, respectively. The haploid DNA content of this species was 0.79 pg/cell which correspond to $46.5\%$ of carp and to $22.6\%$ of mammals. Spotted flounder had the 2n = 46 acrocentric chromosomes but no heteromorphic sex chromosomes was found. Mitochondrial DNA gene for 12S ribosomal RNA was amplified by polymerase chain reaction (PCR) and the PCR products were subjected to digestion with 15 restriction endonucleases. Restriction enzyme analyses revealed that Ava I, Mae II, Sma I and Xba I had one restriction site in the mitochondrial 12S rRNA gene segment of spotted flounder, while Mae I had two. Segments of 12S rRNA gene from mitochondria in spotted flounder were sequenced and compared with channel catfish and human as controls. The 12S rRNA gene of this species was more similar to that of channel catfish than to human's.

• Journal of Nutrition and Health
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• v.54 no.4
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• pp.335-341
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• 2021

Purpose: Muscle mitochondria play a key role in regulating fatty acid and glucose metabolism. Dysfunction of muscle mitochondria is associated with metabolic diseases such as obesity and type 2 diabetes. Isorhamnetin (ISOR), also known as 3-O-methylquercetin, a quercetin metabolite, is a naturally occurring flavonoid in many plants. This study evaluated the effects of ISOR on the regulation of the mitochondrial function of C2C12 muscle cells. Methods: C2C12 muscle cells were differentiated for 5 days, and then treated in various concentrations of ISOR. Cytotoxicity was determined by assessing cell viability using the water-soluble tetrazolium salt-8 assay principle at different concentrations of ISOR and time points. Levels of the mitochondrial DNA (mtDNA) content and gene expression were measured by quantitative real-time polymerase chain reaction. The citrate synthase (CS) activity was quantified by the enzymatic method. Results: ISOR at a concentration of 10 µM did not show any cytotoxic effects. ISOR increased the mtDNA copy number in a time- or dose-dependent manner. The messenger RNA levels of genes involved in mitochondrial function, such as peroxisome proliferator-activated receptor-γ coactivator-1α, and uncoupling protein 3 were significantly stimulated by the ISOR treatment. The CS activity was also significantly increased in a time- or dose-dependent manner. Conclusion: These results suggest that ISOR enhances the regulation of mitochondrial function, which was at least partially mediated via the stimulation of the mtDNA replication, mitochondrial gene expression, and CS activity in C2C12 muscle cells. Therefore, ISOR may be useful as a potential food ingredient to prevent metabolic diseases-associated muscle mitochondrial dysfunction.

• Nutrition Research and Practice
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• v.16 no.2
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• pp.147-160
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• 2022

BACKGROUND/OBJECTIVES: Patients with chronic kidney disease (CKD) have a high concentration of uremic toxins in their blood and often experience muscle atrophy. Indoxyl sulfate (IS) is a uremic toxin produced by tryptophan metabolism. Although an elevated IS level may induce muscle dysfunction, the effect of IS on physiological concentration has not been elucidated. Additionally, the effects of ursolic acid (UA) on muscle hypertrophy have been reported in healthy models; however, it is unclear whether UA ameliorates muscle dysfunction associated with chronic diseases, such as CKD. Thus, this study aimed to investigate whether UA can improve the IS-induced impairment of mitochondrial biogenesis. MATERIALS/METHODS: C2C12 cells were incubated with or without IS (0.1 mM) and UA (1 or 2 μM) to elucidate the physiological effect of UA on CKD-related mitochondrial dysfunction and its related mechanisms using real-time reverse transcription-polymerase chain reaction, western blotting and enzyme-linked immunosorbent assay. RESULTS: IS suppressed the expression of differentiation marker genes without decreasing cell viability. IS decreased the mitochondrial DNA copy number and ATP levels by downregulating the genes pertaining to mitochondrial biogenesis (Ppargc1a, Nrf1, Tfam, Sirt1, and Mef2c), fusion (Mfn1 and Mfn2), oxidative phosphorylation (Cycs and Atp5b), and fatty acid oxidation (Pdk4, Acadm, Cpt1b, and Cd36). Furthermore, IS increased the intracellular mRNA and secretory protein levels of interleukin (IL)-6. Finally, UA ameliorated the IS-induced impairment in C2C12 cells. CONCLUSIONS: Our results indicated that UA improves the IS-induced impairment of mitochondrial biogenesis by affecting differentiation, ATP levels, and IL-6 secretion in C2C12 cells. Therefore, UA could be a novel therapeutic agent for CKD-induced muscle dysfunction.

• Nutrition Research and Practice
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• v.16 no.1
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• pp.14-32
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• 2022

BACKGROUND/OBJECTIVES: Peroxisome proliferator-activated receptor-gamma co-activator-1α (PGC-1α) has a central role in regulating muscle differentiation and mitochondrial metabolism. PGC-1α stimulates muscle growth and muscle fiber remodeling, concomitantly regulating lactate and lipid metabolism and promoting oxidative metabolism. Gynostemma pentaphyllum (Thumb.) has been widely employed as a traditional herbal medicine and possesses antioxidant, anti-obesity, anti-inflammatory, hypolipemic, hypoglycemic, and anticancer properties. We investigated whether G. pentaphyllum extract (GPE) and its active compound, gypenoside L (GL), affect muscle differentiation and mitochondrial metabolism via activation of the PGC-1α pathway in murine C2C12 myoblast cells. MATERIALS/METHODS: C2C12 cells were treated with GPE and GL, and quantitative reverse transcription polymerase chain reaction and western blot were used to analyze the mRNA and protein expression levels. Myh1 was determined using immunocytochemistry. Mitochondrial reactive oxygen species generation was measured using the 2'7'-dichlorofluorescein diacetate assay. RESULTS: GPE and GL promoted the differentiation of myoblasts into myotubes and elevated mRNA and protein expression levels of Myh1 (type IIx). GPE and GL also significantly increased the mRNA expression levels of the PGC-1α gene (Ppargc1a), lactate metabolism-regulatory genes (Esrra and Mct1), adipocyte-browning gene fibronectin type III domain-containing 5 gene (Fndc5), glycogen synthase gene (Gys), and lipid metabolism gene carnitine palmitoyltransferase 1b gene (Cpt1b). Moreover, GPE and GL induced the phosphorylation of AMP-activated protein kinase, p38, sirtuin1, and deacetylated PGC-1α. We also observed that treatment with GPE and GL significantly stimulated the expression of genes associated with the anti-oxidative stress response, such as Ucp2, Ucp3, Nrf2, and Sod2. CONCLUSIONS: The results indicated that GPE and GL enhance exercise performance by promoting myotube differentiation and mitochondrial metabolism through the upregulation of PGC-1α in C2C12 skeletal muscle.

• Journal of Microbiology and Biotechnology
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• v.30 no.12
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• pp.1885-1895
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• 2020

Rumex japonicus Houtt (RJH) is a valuable plant used in traditional medicine to treat several diseases, such as scabies and jaundice. In this study, Jurkat cell growth inhibitory extracts of R. japonicus roots were subjected to bioassay-guided fractionation, resulting in the isolation of three naphthalene derivatives (3-5) along with one anthraquinone (6) and two phenolic compounds (1 and 2). Among these compounds, 2-methoxystypandrone (5) exhibited potent anti-proliferative effects on Jurkat cells. Analysis by flow cytometry confirmed that 2-methoxystypandrone (5) could significantly reduce mitochondrial membrane potential and promote increased levels of mitochondrial reactive oxygen species (ROS), suggesting a strong mitochondrial depolarization effect. Real-time quantitative polymerase chain reaction (qPCR) analysis was also performed, and the results revealed that the accumulation of ROS was caused by reduced mRNA expression levels of heme oxygenase (HO-1), catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD). In addition, 2-methoxystypandrone (5) triggered strong apoptosis that was mediated by the arrest of the G0/G1 phase of the cell cycle. Furthermore, 2-methoxystypandrone (5) downregulated p-IκB-α, p-NF-κB p65, Bcl2, and Bcl-xl and upregulated BAX proteins. Taken together, these findings revealed that 2-methoxystypandrone (5) isolated from RJH could potentially serve as an early lead compound for leukemia treatment involving intracellular signaling by increasing mitochondrial ROS and exerting anti-proliferative effects.

• Nutrition Research and Practice
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• v.17 no.5
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• pp.827-843
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• 2023

BACKGROUND/OBJECTIVES: Mitochondrial DNA leakage leads to inflammatory responses via endosome activation. This study aims to evaluate whether the perennial grass water extract (Pogonatherum panicum) ameliorate mitochondrial DNA (mtDNA) leakage. MATERIALS/METHODS: The major bioactive constituents of P. paniceum (PPW) were investigated by high-performance liquid chromatography, after which their antioxidant activities were assessed. In addition, RAW 264.7 macrophages were stimulated with lipopolysaccharide, resulting in mitochondrial damage. Quantitative polymerase chain reaction and enzyme-linked immunosorbent assay were used to examine the gene expression and cytokines. RESULTS: Our results showed that PPW extract-treated activated cells significantly decrease reactive oxygen species and nitric oxide levels by reducing the p2^phox and iNOS expression and lowering cytokine-encoding genes, including IL-6, TNF-α, IL-1β, PG-E2 and IFN-γ relative to the lipopolysaccharide (LPS)-activated macrophages. Furthermore, we observed that LPS enhanced the mtDNA leaked into the cytoplasm, increasing the transcription of Tlr9 and signaling both MyD88/Irf7-dependent interferon and MyD88/NF-κb p65-dependent inflammatory cytokine mRNA expression but which was alleviated in the presence of PPW extract. CONCLUSIONS: Our data show that PPW extract has antioxidant and anti-inflammatory activities by facilitating mtDNA leakage and lowering the Tlr9 expression and signaling activation.

• Journal of Pharmacopuncture
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• v.15 no.3
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• pp.31-38
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• 2012

Sophorae Radix (SR) plays a role in a number of physiologic and pharmacologic functions in many organs. Objective: The aim of this study was to clarify the potential role for transient receptor potential melastatin 7 (TRPM7) channels in SR-inhibited growth and survival of AGS and MCF-7 cells, the most common human gastric and breast adenocarcinoma cell lines. Methods: The AGS and the MCF-7 cells were treated with varying concentrations of SR. Analyses of the caspase-3 and - 9 activity, the mitochondrial depolarization and the poly (ADPribose) polymerase (PARP) cleavage were conducted to determine if AGS and MCF-7 cell death occured by apoptosis. TRPM7 channel blockers ($Gd^{3+}$ or 2-APB) and small interfering RNA (siRNA) were used in this study to confirm the role of TRPM7 channels. Furthermore, TRPM7 channels were overexpressed in human embryonic kidney (HEK) 293 cells to identify the role of TRPM7 channels in AGS and MCF-7 cell growth and survival. Results: The addition of SR to a culture medium inhibited AGS and MCF-7 cell growth and survival. Experimental results showed that the caspase-3 and -9 activity, the mitochondrial depolarization, and the degree of PARP cleavage was increased. TRPM7 channel blockade, either by $Gd^{3+}$ or 2-APB or by suppressing TRPM7 expression with small interfering RNA, blocked the SR-induced inhibition of cell growth and survival. Furthermore, TRPM7 channel overexpression in HEK 293 cells exacerbated SR-induced cell death. Conclusions: These findings indicate that SR inhibits the growth and survival of gastric and breast cancer cells due to a blockade of the TRPM7 channel activity. Therefore, TRPM7 channels may play an important role in the survival of patients with gastric and breast cancer.

• Journal of Preventive Medicine and Public Health
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• v.45 no.4
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• pp.235-243
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• 2012

Objectives: Nail has been a substitute DNA source for genotyping. To investigate the integrity and consistency of nail DNA amplification for biomarker study, nail clippings from 12 subjects were collected at monthly intervals. The possibility of longer amplification and existence of GAPDH RNA/protein, were also investigated with three nail samples. Methods: Three primer sets were designed for quantitative amplification of nuclear and mitochondrial genes and analysis of their consistency. The mean threshold cycles in amplification of the target genes were compared to test the consistency of polymerase chain reaction (PCR) performance among individual factors including age groups, sex, family, the nail source, and by the size of the amplification segments. Results: The amplification of the target genes from nail DNA showed similar integrity and consistency between the nail sources, and among the serial collections. However, nail DNA from those in their forties showed earlier threshold cycles in amplification than those in their teens or seventies. Mitochondrial DNA (mtDNA) showed better DNA integrity and consistency in amplification of all three targets than did nuclear DNA (nucDNA). Over 9 kb of mtDNA was successfully amplified, and nested quantitative PCR showed reliable copy numbers (%) between the two loci. Reverse transcription PCR for mRNA and immunoblotting for GAPDH protein successfully reflected their corresponding amounts. Regarding the existence of RNA and protein in nails, more effective extraction and detection methods need to be set up to validate the feasibility in biomarker study. Conclusions: Nail DNA might be a feasible intra-individual monitoring biomarker. Considering integrity and consistency in target amplification, mtDNA would be a better target for biomarker research than nucDNA.