• Preventive Nutrition and Food Science
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• 제21권4호
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• pp.317-322
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• 2016

Mitochondrial biogenesis is a complex process requiring coordinated expression of nuclear and mitochondrial genomes. The peroxisome proliferator-activated receptor gamma co-activator 1-alpha (PGC-$1{\alpha}$) is a key regulator of mitochondrial biogenesis, and it controls mitochondrial DNA (mtDNA) replication within diverse tissues, including muscle tissue. The aim of this study was to investigate the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on mtDNA copy number and PGC-$1{\alpha}$ promoter activity in $C_2C_{12}$ muscle cells. mtDNA copy number and mRNA levels of genes related to mitochondrial biogenesis such as PGC-$1{\alpha}$, nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (Tfam) were assayed by quantitative real-time PCR. The PGC-$1{\alpha}$ promoter from -970 to +412 bp was subcloned into the pGL3-basic vector, which includes a luciferase reporter gene. Both EPA and DHA significantly increased mtDNA copy number, dose and time dependently, and up-regulated mRNA levels of PGC-$1{\alpha}$, NRF1, and Tfam. Furthermore, EPA and DHA stimulated PGC-$1{\alpha}$ promoter activity in a dose-dependent manner. These results suggest that EPA and DHA may modulate mitochondrial biogenesis, which was partially associated with increased mtDNA replication and PGC-$1{\alpha}$ gene expression in $C_2C_{12}$ muscle cells.

• Applied Microscopy
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• 제51권
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• pp.20.1-20.12
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• 2021

We explored the link between mitochondrial biogenesis and mitochondrial morphology using transmission electron microscopy (TEM) in lymphoblasts of pediatric acute lymphoblastic leukemia (ALL) patients and compared these characteristics between tumors and control samples. Gene expression of mitochondrial biogenesis markers was analysed in 23 ALL patients and 18 controls and TEM for morphology analysis was done in 15 ALL patients and 9 healthy controls. The area occupied by mitochondria per cell and the cristae cross-sectional area was observed to be significantly higher in patients than in controls (p-value=0.0468 and p-value<0.0001, respectively). The mtDNA copy numbers, TFAM, POLG, and c-myc gene expression were significantly higher in ALL patients than controls (all p-values<0.01). Gene Expression of PGC-1α was higher in tumor samples. The analysis of the correlation between PGC-1α expression and morphology parameters i.e., both M/C ratio and cristae cross-sectional area revealed a positive trend (r=0.3, p=0.1). The increased area occupied by mitochondria and increased cristae area support the occurrence of cristae remodelling in ALL. These changes might reflect alterations in cristae dynamics to support the metabolic state of the cells by forming a more condensed network. Ultrastructural imaging can be useful for affirming changes occurring at a subcellular organellar level.

• The Korean Journal of Physiology and Pharmacology
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• 제25권2호
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• pp.167-175
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• 2021

Far-infrared rays (FIR) are known to have various effects on atoms and molecular structures within cells owing to their radiation and vibration frequencies. The present study examined the effects of FIR on gene expression related to glucose transport through microarray analysis in rat skeletal muscle cells, as well as on mitochondrial biogenesis, at high and low glucose conditions. FIR were emitted from a bio-active material coated fabric (BMCF). L6 cells were treated with 30% BMCF for 24 h in medium containing 25 or 5.5 mM glucose, and changes in the expression of glucose transporter genes were determined. The expression of GLUT3 (Slc2a3) increased 2.0-fold (p < 0.05) under 5.5 mM glucose and 30% BMCF. In addition, mitochondrial oxygen consumption and membrane potential (ΔΨm) increased 1.5- and 3.4-fold (p < 0.05 and p < 0.001), respectively, but no significant change in expression of Pgc-1a, a regulator of mitochondrial biogenesis, was observed in 24 h. To analyze the relationship between GLUT3 expression and mitochondrial biogenesis under FIR, GLUT3 was down-modulated by siRNA for 72 h. As a result, the ΔΨm of the GLUT3 siRNA-treated cells increased 3.0-fold (p < 0.001), whereas that of the control group increased 4.6-fold (p < 0.001). Moreover, Pgc-1a expression increased upon 30% BMCF treatment for 72 h; an effect that was more pronounced in the presence of GLUT3. These results suggest that FIR may hold therapeutic potential for improving glucose metabolism and mitochondrial function in metabolic diseases associated with insufficient glucose supply, such as type 2 diabetes.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2008년도 Proceedings of the Convention
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• pp.23-30
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• 2008

Mitochondria biogenesis requires a coordination of two genomes, nuclear DNA (nDNA) and mitochondrial DNA (mtDNA). Disruption of mitochondria function leads to a loss of mitochondrial membrane potential and ATP generating capacity and consequently results in chronic degenerative diseases including insulin resistance, metabolic syndrome and neurodegenerative diseases. Although PPAR-${\gamma}$ coactivator-$1{\alpha}$ (PGC-$1{\alpha}$) was discovered as a central regulator of mitochondria biogenesis and a transcriptional co-activator of nuclear respiratory factor (NRF) and mitochondrial transcription factor A (Tfam), the expressions of PGC-$1{\alpha}$, NRF and Tfam were not significantly altered in tissues showing abnormal mitochondria functions. This observation suggests that there should be another regulator(s) for mitochondria function. Here, we demonstrate microRNAs (miRNAs) can modulate mitochondria function. Overexpression of microRNA dissipated mitochondrial membrane potential and increased ROS production in vitro and in vivo. It will be discussed the target of microRNA and its role in metabolic syndrome.

• The Korean Journal of Physiology and Pharmacology
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• 제21권6호
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• pp.633-641
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• 2017

The aim of this study is to investigate the effects of intermittent ladder-climbing exercise training on mitochondrial biogenesis and ER stress of the cardiac muscle in high fat diet-induced obese middle-aged rats. We induced obesity over 6 weeks of period in 40 male Sprague-Dawley rats around 50 weeks old, and were randomly divided into four experimental groups: chow, HFD, exercise+HFD, and exercise+chow. The exercising groups underwent high-intensity intermittent training using a ladder-climbing and weight exercise 3 days/week for a total of 8 weeks. High-fat diet and concurrent exercise resulted in no significant reduction in body weight but caused a significant reduction in visceral fat weight (p<0.05). Expression of $PPAR{\delta}$ increased in the exercise groups and was significantly increased in the high-fat diet+exercise group (p<0.05). Among the ER stress-related proteins, the expression levels of p-PERK and CHOP, related to cardiac muscle damage, were significantly higher in the cardiac muscle of the high-fat diet group (p<0.05), and were significantly reduced by intermittent ladder-climbing exercise training (p<0.05). Specifically, this reduction was greater when the rats underwent exercise after switching back to the chow diet with a reduced caloric intake. Collectively, these results suggest that the combination of intermittent ladder-climbing exercise training and a reduced caloric intake can decrease the levels of ER stress-related proteins that contribute to cardiac muscle damage in obesity and aging. However, additional validation is required to understand the effects of these changes on mitochondrial biogenesis during exercise.

• Nutrition Research and Practice
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• 제11권2호
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• pp.121-129
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• 2017

BACKGROUND/OBJECTIVES: The study was conducted to evaluate the effects of dietary leucine supplementation on mitochondrial biogenesis and energy metabolism in the liver of normal birth weight (NBW) and intrauterine growth-retarded (IUGR) weanling piglets. MATERIALS/METHODS: A total of sixteen pairs of NBW and IUGR piglets from sixteen sows were selected according to their birth weight. At postnatal day 14, all piglets were weaned and fed either a control diet or a leucine-supplemented diet for 21 d. Thereafter, a $2{\times}2$ factorial experimental design was used. Each treatment consisted of eight replications with one piglet per replication. RESULTS: Compared with NBW piglets, IUGR piglets had a decreased (P < 0.05) hepatic adenosine triphosphate (ATP) content. Also, IUGR piglets exhibited reductions (P < 0.05) in the activities of hepatic mitochondrial pyruvate dehydrogenase (PDH), citrate synthase (CS), ${\alpha}$-ketoglutarate dehydrogenase (${\alpha}$-KGDH), malate dehydrogenase (MDH), and complexes I and V, along with decreases (P < 0.05) in the concentration of mitochondrial DNA (mtDNA) and the protein expression of hepatic peroxisome proliferator-activated receptor-${\gamma}$ coactivator $1{\alpha}$ (PGC-$1{\alpha}$). Dietary leucine supplementation increased (P < 0.05) the content of ATP, and the activities of CS, ${\alpha}$-KGDH, MDH, and complex V in the liver of piglets. Furthermore, compared to those fed a control diet, piglets given a leucine-supplemented diet exhibited increases (P < 0.05) in the mtDNA content and in the mRNA expressions of sirtuin 1, PGC-$1{\alpha}$, nuclear respiratory factor 1, mitochondrial transcription factor A, and ATP synthase, $H^+$ transporting, mitochondrial F1 complex, ${\beta}$ polypeptide in liver. CONCLUSIONS: Dietary leucine supplementation may exert beneficial effects on mitochondrial biogenesis and energy metabolism in NBW and IUGR weanling piglets.

• 생명과학회지
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• 제29권8호
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• pp.837-845
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• 2019

본 연구에서는 고지방식이로 유발된 비만 쥐의 골격근에서 유산소 운동과 레스베라트롤 투여가 미토콘드리아 생합성에 미치는 영향을 조사하였다. 4주령 C57BL/6의 수컷 쥐를 이용하여, 일반 식이 그룹(NC, n=10), 고지방식이 그룹(HR, n=10), 레스베라트롤 투여와 고지방식이 그룹(HRe, n=10), 유산소 운동 그룹(HE, n=10)으로 분류하였다. 유산소 운동은 16주 동안 40~60 min/day 동안 10-14m/min, 0% grade의 강도로 주당 4회 트레드밀 운동을 실시하였고, 레스베라트롤은 16주 동안 1일 1회, 주당 4회 체중 당 25 mg/kg을 투여하였다. COX-IV mRNA 발현은 NC와 HC 그룹 간에 유의한 차이가 있었으며(p<0.05), HE 그룹의 SIRT-3, $PGC-1{\alpha}$ 및 COX-IV mRNA 발현은 HC 및 HRe 그룹에 비해 유의하게 증가하였다(p<0.05). 또한, 오직 HE 그룹의 $PGC-1{\alpha}$ 및 COX-IV mRNA의 발현만이 HC 그룹에 비해 유의하게 증가하였다(p<0.05). 이상의 결과를 종합해보면, 고지방식이로 유발된 비만 쥐는 골격근에서 미토콘드리아 생합성 유전자 발현에 영향을 나타내지 않는 것으로 보인다. 하지만, 유산소 운동 훈련은 고지방식이로 유발된 비만 쥐의 골격근에서 미토콘드리아 생합성 유전자 발현을 증가시키는 것으로 나타났다. 이러한 연구 결과는 레스베라트롤 투여가 아닌 유산소 운동이 고지방식이로 유도된 쥐의 골격근에서 미토콘드리아 생합성에 긍정적인 영향을 미친다는 것을 시사한다.

• 한국발생생물학회지:발생과생식
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• 제14권2호
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• pp.75-82
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• 2010

이 연구는 제2형 당뇨 모델 동물인 Goto-Kakizaki(GK) 흰쥐를 사용하여 운동과 셀레늄 투여가 미토콘드리아 생성과 기능 향상을 조절하는 전사 인자의 발현 변화와 현상학적으로 당뇨의 증상 개선을 유도할 수 있는지를 구명하기 위해 실시하였다. 실험동물은 52주령된 GK 수컷 흰쥐로 24 m/min, 30 min/day, 5 days/week, 총 6주간 트레드밀 런닝을 실시하였다. Sodium selenite(5 umol/kg)는 selenium 집단과 combination 집단에 1주일에 5일씩 6주간 복강에 주입하였다. 운동과 셀레늄 투여는 미토콘드리아의 생성에 관여하는 peroxisome proliferators-activated receptor gamma coactivator-1alpha(PGC-$1{\alpha}$), nuclear respiratory factors(NRF-1), 그리고 mitochondrial transcription factor A(Tfam) 발현을 증가시켰으며, 그 결과로 미토콘드리아량의 지표 단백질인 cytochrome C도 증가를 보였다. 특히, 운동이나 셀레늄의 단독적인 처치보다는 운동과 셀레늄 병행 처치가 미토콘드리아의 생성 및 활성 증가, 그리고 포도당 내성에 긍정적인 효과를 보였다. 따라서, 본 연구에서 수행된 운동과 셀레늄 투여 처치는 당뇨의 개선 효과 및 당뇨 질환과 관련된 미토콘드리아의 기능 향상에 긍정적인 효과를 보이는 것으로 나타났다.

• 생명과학회지
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• 제28권12호
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• pp.1455-1460
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• 2018

최근 들어 급속한 고령화 사회가 진행되고 있으며 이로 인해 골관절염과 골다공증 등의 퇴행성 골질환 환자수도 동반하여 증가하고 있다. 따라서 고령화에 따른 골관련 질환의 새로운 제어와 치료법 개발을 위해 성체줄기세포의 골세포 분화유도를 활용한 재생의학도 활발히 연구되고 있다. 또한 관련 연구에서 줄기세포의 분화과정에서 미토콘드리아의 산화적인산화가 중요하다고 알려지고 있다. 흥미롭게도 최근 연구에서 아스피린의 주성분인 salicylate가 동물세포의 미토콘드리아 생합성을 증진시키는 효과가 보고되었다. 그러나 성체줄기세포에서 salicylate가 골세포분화나 미토콘드리아 생합성을 유도할 수 있는지에 대한 연구결과는 미비한 실정이다. 본 연구에서는 인체 골막 유래의 성체줄기세포를 이용하여 골세포분화나 미토콘드리아 생합성에 대한 salicylate의 영향을 분석하였다. 골막 유래 성체줄기세포의 골세포 분화유도 과정에 동반한 salicylate 처리는 잘 알려진 골세포분화 표지자인 alkaline phosphatase의 활성을 증가시키는 결과를 본 연구에서 얻었다. 이러한 연구결과는 salicylate가 줄기세포로부터 골세포로의 분화를 조절할 수 있는 물질이 될 수 있음을 제시한다. 또한 이러한 골세포 분화과정에서 미토콘드리아 생합성도 salicylate 처리에 의해 증가됨이 관찰되었다. 따라서, 미토콘드리아 생합성이나 기능을 조절하는 물질이 성체줄기세포의 골세포 분화과정에도 영향을 줄 수 있으며, 이러한 물질이 골세포분화나 재생의학의 새로운 조절 물질로 응용될 수 있음을 제시한다.

• 한국식품과학회지
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• 제49권6호
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• pp.685-692
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• 2017

극심한 스트레스, 서구화된 식습관, 불규칙한 생활리듬 등에 의한 부족한 신체활동은 체력을 약화시키고 비만, 당뇨, 고혈압, 우울증, 근감소증 등을 야기한다. 본 연구에서는 ARC가 운동능력 증진에 미치는 효능을 세포 및 동물실험을 통해 검증하였다. ARC를 처리함에 따라 근육 세포 내에서 p-AMPK와 SIRT1 단백질, PGC-$1{\alpha}$, NFR1, TFAM mRNA 발현양과 미토콘드리아 양이 증가하였다. 세포실험에서 ARC는 RGE와 AE단독으로 처리에 비해 ATP 생성을 더 많이 하였으며, 동물실험에서도 RGE군과 AE군에 비해 ARC군에서 운동수행능력이 더 향상시켰다. 세포 실험과 마찬가지로 ARC는 동물의 근육 조직 내에서 미토콘드리아 생합성에 관련된 유전자의 발현을 증가시켰으며, 젖산 발생량 감소 및 산화스트레스 억제로 인해 운동으로 인한 피로를 쉽게 회복시켰다. 따라서, 신선초와 홍삼 복합물에 대한 인체수준에서 과학적인 증거 및 안전성이 확보될 경우, 운동수행능력 향상을 위한 기능성 소재로서의 산업적인 활용이 확대될 것으로 기대된다.