• Title/Summary/Keyword: AMPK phosphorylation

Search Result 145, Processing Time 0.023 seconds

Effects of steamed Polygonatum odoratum extract on inhibition of adipocyte differentiation and lowing lipid in 3T3-L1 adipocytes (증자 둥굴레 추출물의 3T3-L1 지방세포에서 분화억제 및 지질강하 효과)

  • Kang, Byung Tae;Choe, Won Kyung;Park, Dong Cheol;Kim, Jong Kuk;Park, Mora;Kim, Sung Ok;Kim, Mi Ryeo
    • The Korea Journal of Herbology
    • /
    • v.29 no.2
    • /
    • pp.15-21
    • /
    • 2014
  • Objectives : The purpose of this study was to investigate inhibitory effects of steamed Polygonatum odoratum extract (POE) on differentiation and adipogenesis in 3T3-L1 adipocytes. Methods : Polygonatum odoratum (P. odoratum) extract was extracted with ethyl acetate. Total phenolic and flavonoid contents in POE were measured for antioxidant activity. The spectrophotometric method was used to determine the DPPH and ABTS radical scavenging activity and ferric-reducing antioxidant potential (FRAP). MTT assay was examined for cell toxicity, oil red O staining was performed for intracelluar adipogenesis in differentiated 3T3-L1 adipocytes. Western blot analysis for measurement of CCAAT/enhancer-binding protein ${\alpha}$ ($C/EBP{\alpha}$), peroxisome proliferator-activated receptor${\gamma}$ ($PPAR{\gamma}$) and AMP-activated protein kinase (AMPK) expressions were performed. Results : The results revealed that POE has antioxidant activities. Contents of total polyphenolics and flavonoids were $50.83{\pm}1.52$ GAE mg/100g dry weight of POE and $17.05{\pm}2.47$ RE mg/100g dry weight of POE, respectively. DPPH radical scavenging activity, and FRAP in 10 mg/ml concentration were $92.1{\pm}0.6%$, $244.8{\pm}9.0{\mu}M$ Fe(II) and ABTS inhibition in 5 mg/ml concentration was $84.8{\pm}4.1%$. Treatment of POE in adipocytes inhibited the differentiation and adipogenesis of 3T3-L1 adipocytes compared to those of vehicle control. Additionally, protein expressions of $C/EBP{\alpha}$ and $PPAR{\gamma}$, major transcription factor for the adipogenic genes, were significantly decreased compared to those of vehicle control (p<0.05). Futhermore, phosphorylation of AMPK was increased in 3T3-L1 adipocytes treated with POE compared to that of vehicle control (p<0.05). Conclusions : we demonstrate that steamed P. odoratum extract (POE) has potentiating antioxidant activities, inhibits differentiation and lipid accumulation and also induces energy expenditure in adipocytes, which may contribute to antiobesity property.

Valproic Acid-induced PPAR-alpha and FGF21 Expression Involves Survival Response in Hepatocytes (Valproic acid에 의해 증가하는 PPAR-alpha 및 FGF21의 발현이 간세포 생존에 미치는 영향)

  • Bakhovuddin Azamov;Yeowon Kang;Chanhee Lee;Wan-Seog Shim;Kwang Min Lee;Parkyong Song
    • Journal of Life Science
    • /
    • v.34 no.4
    • /
    • pp.227-235
    • /
    • 2024
  • Hepatocyte damage caused by medications or herbal products is one of the important problem when these compounds are chronically administrated. Thus, improving hepatocyte survival during treatment offers a wide range of opportunities. Valproic acid (VPA), a branched short-chain fatty acid derived from naturally occurring valeric acid, is commonly used to treat epilepsy and seizures. Although VPA exerts numerous effects in cancer, HIV therapy, and neurodegenerative disease, its effects on the liver and its mechanism of action have not been fully elucidated. Here, we demonstrated that VPA caused moderate liver cell toxicity and apoptosis. Interestingly, VPA treatment increased transcription levels of PPAR alpha (PPAR-α) and fibroblast growth factor 21 (FGF21) in murine (Hepa1c1c7) hepatoma cells in a time and concentration dependent manner. VPA-induced FGF21 expression was significantly weaker under PPAR-α silencing condition than in cells transfected with non-targeting control siRNA. Subsequent experiments showed that cell viability was significantly lowered when the FGF21 signaling pathway was blocked by FGF receptor antagonist. Finally, we further determined that AMPK phosphorylation was not responsible for VPA-induced FGF21 expression and PPAR-a increments. These results indicate that increases of FGF21 expression alleviate VPA-induced hepatic toxicity, thereby making FGF21 a potential biomarker for predicting liver damage during VPA treatments.

Effect of Bisphenol A on Insulin-Mediated Glucose Metabolism In Vivo and In Vitro

  • Ko, Jeong-Hyeon;Kang, Ju-Hee;Park, Chang-Shin;Shin, Dong-Wun;Kim, Ji-Hye;Kim, Hoon;Han, Seung-Baik
    • Molecular & Cellular Toxicology
    • /
    • v.4 no.4
    • /
    • pp.348-354
    • /
    • 2008
  • Bisphenol A (BPA), an environmental endocrine disrupter, enters the human body continuously in food and drink. Young children are likely to be more vulnerable than adults to chemical exposure due to the immaturities of their organ systems, rapid physical development, and higher ventilation, metabolic rates, and activity levels. The direct effect of BPA on peripheral tissue might also be of importance to the development of insulin resistance. However, the influence that BPA has on insulin signaling molecules in skeletal muscle has not been previously investigated. In this study, we examined the effect of BPA on fasting blood glucose (FBG) in post-weaned Wistar rats and on insulin signaling proteins in C2C12 skeletal muscle cells. Subsequently, we investigated the effects of BPA on insulin-mediated Akt phosphorylation in C2C12 myotubes. In rats, BPA treatment (0.1-1,000 ng/mL for 24 hours) resulted in the increase of FBG and plasma insulin levels, and reduced insulin-mediated Akt phosphorylation. Furthermore, the mRNA expression of insulin receptor (IR) was decreased after 24 hours of BPA treatment in C2C12 cells in a dose-dependent manner, whereas the mRNA levels of other insulin signaling proteins, including insulin receptor substrate-1 (IRS-1) and 5'-AMP-dependent protein kinase (AMPK), were unaffected. Treatment with BPA increased GLUT4 expression and protein tyrosine phosphatase 1B (PTP1B) activity in C2C12 myotubes, but not in protein levels. We conclude that exposure to BPA can induce insulin resistance by decreasing IR gene expression, which is followed by a decrease in insulin- mediated Akt activation and increased PTP1B activity.

Effects of Chamaeneron angustifolia Extract on Lipid Metabolism and Differentiation of 3T3-L1 Preadipocyte (Chamaeneron angustifolia 추출물이 3T3-L1 Preadipocyte의 지방대사 및 분화에 미치는 영향)

  • Seul Bi Lee;Moon-Yeol Choi;Mi Hyung Kim;So-Young Kim;Mi Ryeo Kim
    • The Korea Journal of Herbology
    • /
    • v.39 no.4
    • /
    • pp.29-35
    • /
    • 2024
  • Objectives : Obesity is an imbalance between energy intake and consumption due to overeating and lack of exercise, and if it persists, it increases non-infectious diseases such as high blood pressure, diabetes, and hyperlipidemia. In this study, we tried to investigate the possibility of using Chamaeneron angustifolia (CA) as a material for anti-obesity by confirming the effect of inhibiting lipid differentiation. Methods : We measured the effects of CA extract on oil-red-o staining, cell cytotoxicity evaluation activity using 3T3-L1 cells. Additionally, we assessed fat decomposition and metabolism-related protein expression through Western blot analysis. Results : In this study, the anti-obesity effects of CA extract were experimentally assessed. Results showed significant inhibition of adipocyte differentiation and accumulation at concentrations of 0.05, 0.1, and 0.2 mg/ml of oil-red-o staining, with reductions of 80% or more. CA notably increased the phosphorylation of AMPK protein expression compared to the control group across all concentrations. Additionally, phosphorylation of ACC significantly increased at a concentration of 0.2 mg/ml compared to the control. PPAR-γ, which regulates adipogenesis, exhibited a significant decrease compared to the control, while protein expression of CPT-1, involved in fatty acid oxidation, showed a concentration-dependent increase across all groups. Therefore, CA extract demonstrates potential as a functional material for anti-obesity by increasing the expression of proteins related to fat decomposition and synthesis while decreasing others. Conclusions : These results suggest that CA may also be useful as an anti-obesity functional substance.

Korean Red Ginseng attenuates ethanol-induced steatosis and oxidative stress via AMPK/Sirt1 activation

  • Han, Jae Yun;Lee, Sangkyu;Yang, Ji Hye;Kim, Sunju;Sim, Juhee;Kim, Mi Gwang;Jeong, Tae Cheon;Ku, Sae Kwang;Cho, Il Je;Ki, Sung Hwan
    • Journal of Ginseng Research
    • /
    • v.39 no.2
    • /
    • pp.105-115
    • /
    • 2015
  • Background: Alcoholic steatosis is the earliest and most common liver disease, and may precede the onset of more severe forms of liver injury. Methods: The effect of Korean Red Ginseng extract (RGE) was tested in two murine models of ethanol (EtOH)-feeding and EtOH-treated hepatocytes. Results: Blood biochemistry analysis demonstrated that RGE treatment improved liver function. Histopathology and measurement of hepatic triglyceride content verified the ability of RGE to inhibit fat accumulation. Consistent with this, RGE administration downregulated hepatic lipogenic gene induction and restored hepatic lipolytic gene repression by EtOH. The role of oxidative stress in the pathogenesis of alcoholic liver diseases is well established. Treatment with RGE attenuated EtOH-induced cytochrome P450 2E1, 4-hydroxynonenal, and nitrotyrosine levels. Alcohol consumption also decreased phosphorylation of adenosine monophosphate-activated protein kinase, which was restored by RGE. Moreover, RGE markedly inhibited fat accumulation in EtOH-treated hepatocytes, which correlated with a decrease in sterol regulatory element-binding protein-1 and a commensurate increase in sirtuin 1 and peroxisome proliferator-activated receptor-a expression. Interestingly, the ginsenosides Rb2 and Rd, but not Rb1, significantly inhibited fat accumulation in hepatocytes. Conclusion: These results demonstrate that RGE and its ginsenoside components inhibit alcoholic steatosis and liver injury by adenosine monophosphate-activated protein kinase/sirtuin 1 activation both in vivo and in vitro, suggesting that RGE may have a potential to treat alcoholic liver disease.

Inhibitory Effect of Cymbopogon Citratus Ethanol Extracts on Adipogenesis in 3T3-L1 Preadipocytes (레몬그라스 에탄올 추출물의 3T3-L1 지방세포 분화 억제효과)

  • Jo, Yong Seok;Ju, Sung Min;Hwang, Keum Hee;Kim, Min Sook;Kim, Kwang Sang;Jeon, Byung Hun
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.33 no.1
    • /
    • pp.17-24
    • /
    • 2019
  • Cymbopogon citratus, commonly know as lemongrass, prossesses strong antioxidant, anti-tumor and anti-inflammatory properties. Howerver, its anti-obesity activity remains to be elucidated. This study investigated the effect of ethanol extract of Cymbopogon citratus on adipogenesis, and its underlying mechanism, in 3T3-L1 preadipocytes. The results demonstrated that ethanol extracts of Cymbopogon citratus effectively suppressed intercellular lipid accumulation at non-toxic concentrations, and was associated with the down-regulation of adipocyte-specific transcription factors, including $C/EBP{\alpha}$ and $PPAR{\gamma}$, and phosphorylation of $AMPK{\alpha}$. Furthermore, ethanol extracts of Cymbopogon citratus increased p21 and p21 expression, while the expression of CDK2, cyclin A and cyclin B1 was reduced. As a result, ethanol extracts of Cymbopogon citratus seems to induce G0/G1 cell cycle arrest of 3T3-L1 cells. On the other hand, ERK and Akt signaling pathways were not involved in anti-adipogenesis by ethanol extracts of Cymbopogon citratus. Taken together, theses results suggest that ethanol extracts of Cymbopogon citratus inhibits adipocyte differentiation in 3T3-L1 cells and can be used as a safe and efficient natural substance to manage anti-obesity.

Effects of Chaenomelis Fructus Extract on the regulation of myoblasts differentiation and the expression of biogenetic factors in C2C12 myotubes (모과추출물의 C2C12 근육세포에서 근분화 및 에너지대사조절인자 발현 증진 효과 연구)

  • Kang, Seok Yong;Hyun, Sun Young;Kwon, Yedam;Park, Yong-Ki;Jung, Hyo Won
    • The Korea Journal of Herbology
    • /
    • v.34 no.6
    • /
    • pp.99-107
    • /
    • 2019
  • Objective : The present study was conducted to investigate the effects of Chaenomelis Fructus (CF) on the regulation of biogenesis in C2C12 mouse skeletal muscle cells. Methods : C2C12 myoblasts were differentiated into myotubes in 2% horse serum-containing medium for 5 days, and then treated with CF extract at different concentrations for 48 hr. The expression of muscle differentiation markers, myogenin and myosin heavy chain (MHC) and mitochondrial biogenesis-regulating factors, peroxisome proliferator-activated receptor gamma coactivator 1alpha (PGC1α), sirtuin1 (Sirt1), nuclear respiratory factor1 (NRF1) and transcription factor A, mitochondrial (TFAM), and the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) were determined in C2C12 myotubes by reverse transcriptase (RT)-polymerase chain reaction (RT-PCR) and western blot, respectively. The cellular glucose levels and total ATP contents were measured by cellular glucose uptake and ATP assays, respectively. Results : Treatment with CF extract (0.01, 0.02, and 0.05 mg/㎖) significantly increased the expression of MHC protein in C2C12 myotubes compared with non-treated cells. CF extract significantly increased the expression of PGC1α and TFAM in the myotubes. Also, CF extract significantly increased glucose uptake levels and ATP contents in the myotubes. Conclusion : CF extract can stimulate C2C12 myoblasts differentiation into myotubes and increase energy production through upregulation of the expression of mitochondrial biogenetic factors in C2C12 mouse skeletal muscle cell. This suggests that CF can help to improve skeletal muscle function with stimulation of the energy metabolism.

Effects of Vitexin from Mung Bean on 3T3-L1 Adipocyte Differentiation and Regulation According to Adipocytokine Secretion (녹두의 Vitexin이 비만전구세포에서 세포분화 및 아디포사이토카인 분비능에 미치는 영향)

  • Wi, Hae-Ri;Choi, Mun-Ji;Choi, Se-Lim;Kim, Ae-Jung;Lee, Myoung-Sook
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.41 no.8
    • /
    • pp.1079-1085
    • /
    • 2012
  • Obesity is an important issue worldwide as it may associated with increased prevalence of metabolic diseases. Mung bean is known as a functional food for decreasing the glycemic index and lipid profile of plasma. The purpose of this study was to investigate the anti-obesity effects of vitexin from mung bean on the regulation of adipocyte differentiation and adipocytokine secretion. When 3T3-L1 adipocytes were treated with vitexin from days 0 to 14 at various levels of 25, 50, 100, and $200{\mu}M$, there was no change in cell viability. Vitexin treatment at 50, 100, and $200{\mu}M$ decreased triacylglycerol levels in cells, but only $100{\mu}M$ vitexin induced lipolysis. At $200{\mu}M$ of vitexin, phosphorylation of p38 and ERK, which causes secretion of inflammatory adipocytokines, was depressed, whereas there was an increase in expression of $PPAR{\gamma}$, the key regulator of adipocyte differentiation. Phosphorylation of AMPK increased at $100{\mu}M$ vitexin. TNF-${\alpha}$ and aP2 mRNA expression increased at $25{\mu}M$ vitexin, whereas only TNF-${\alpha}$ mRNA expression increased at $200{\mu}M$ vitexin. Further, the mRNA levels of TNF-${\alpha}$ and aP2 decreased at other concentrations in a dose-dependent manner. Since we observed that mRNA expression of C/EBP, SREBP1, and $PPAR{\gamma}$ did not change upon vitexin treatment, our future studies will investigate other genes such as mTOR, which is related with apoptosis signaling, or SIRT1, which is associated with inhibition of adipogenesis. Our results indicate that vitexin at concentrations between 100 and $200{\mu}M$ is suitable in vivo for the development of mung bean as an anti-obesity therapy or functional food.

Immunostimulatory and Anti-Obesity Activity of Lonicera insularis Nakai Extracts in Mouse Macrophages RAW264.7 Cells and Mouse Adipocytes 3T3-L1 Cells (섬괴불나무(Lonicera insularis Nakai) 추출물의 면역자극 및 항비만 활성)

  • Yu, Ju Hyeong;Yeo, Joo Ho;Choi, Min Yeong;Lee, Jae Won;Geum, Na Gyeong;An, Mi-Yun;Jeong, Jin Boo
    • Korean Journal of Plant Resources
    • /
    • v.35 no.4
    • /
    • pp.417-427
    • /
    • 2022
  • In this study, we investigated in vitro immuno-stimulatory and anti-obesity activity of fruit (LIF), leaves (LIL) and stems (LIS) from Lonicera insularis Nakai in mouse macrophages RAW264.7 cells and mouse pre-adipocytes 3T3-L1 cells. LIF, LIL and LIS increased the production of immunostimulatory factors such as nitric oxide (NO), inducible nitric oxide synthase (iNOS), interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α) and activated phagocytosis in RAW264.7 cells. Inhibition of toll-like receptor 2/4 (TLR2/4) partly blocked LIF, LIL and LIS mediated production of immunostimulatory factors. In addition, inhibition of mitogen-activated protein kinases (MAPK) signaling attenuated the production of immunostimulatory factors induced by LIF, LIL and LIS. Based on these results of this study, LIF, LIL and LIS is thought to activate macrophages the production of immunostimulatory factors and phagocytosis through toll-like receptor 2/4 (TLR2/4) and MAPKs signaling pathway. In anti-obesity study, LIF reduced the lipid accumulation in 3T3-L1 cells. LIF increased the protein phosphorylation expressions such as AMP-activated protein kinase (AMPK), hormone sensitive lipase (HSL), adipose triglyceride lipase (ATGL) related to the lipolysis of the adipocytes. In addition, LIF increased the expression of proteins involved in energy metabolism and brown adipose tissues differentiation such as peroxisome proliferator-activated receptor gamma coativator 1α (PGC-1α) and PR domain-containing16 (PRDM16). These results suggest that LIF is involved in lipid accumulation inhibition through expressing the proteins such as lipolysis and differentiation of white adipocytes to brown adipocytes.

Inhibition of Differentiation and Anti-Adipogenetic Effect of the Salvia plebeia R. Br. Ethanol Extract in Murine Adipocytes, 3T3-L1 Cells (배암차즈기 에탄올 추출물의 3T3-L1 지방전구세포 분화 억제 및 지방 축적 저해 효과)

  • Kim, Sung-Ok;Kim, Mi-Ryeo;Hwang, Kyung-A;Park, No-Jin;Jeong, Ji-Suk
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.46 no.4
    • /
    • pp.401-408
    • /
    • 2017
  • Salvia plebeia R. Br. (Lamiaceae) has been used in folk medicines in Asian countries, including Korea and China, to treat inflammatory diseases. The focus of our research was on the anti-adipogenic activity of ethanol extract from Salvia plebeia R. Br. (SPE) in 3T3-L1 adipocytes. This study investigated inhibition of differentiation and lipogenesis upon SPE treatment in 3T3-L1 cells. The results reveal that SPE at non-cytotoxic concentration significantly suppressed triglyceride accumulation and reduced expression of peroxisome proliferator-activated receptor gamma, CCAAT/enhancer-binding protein-alpha, and sterol regulatory element-binding protein as adipogenic transcription factors in 3T3-L1 adipocytes compared to non-treated control cells. Inducible phosphorylation of AMP-activated protein kinase, acetyl CoA carboxylase, and hormone-sensitive lipase as well as carnitine palmitoyltransferase-1 mRNA expression increased upon SPE treatment, which suppressed expression of fatty acid synthase. In conclusion, these results demonstrate that SPE can inhibit expression of adipogenic genes in 3T3-L1 adipocytes. Our study suggests that SPE has potential anti-obesity effects and is a novel therapeutic functional agent with anti-adipogenic activity via reduction of lipogenesis.