Non-alcoholic fatty liver disease (NAFLD) is emerging as the most common liver disease in industrialized countries. Recently, natural compounds that may be beneficial for improving NAFLD have received increasing attention. Artemisia annua L. is the source of antimalarial phytomolecule, artemisinin, which has been reported to prevent obesity. However, the effect of A. annua extract on hepatic lipid metabolism remains unclear. This study was performed to determine the protective effect of Artemisia annua extract (AAE) on high-fat diet (HFD)-induced hepatic lipid accumulation, and elucidate the molecular mechanisms behind its effects in vivo and in vitro. We found that HFD-fed mice with AAE administration (50 mg/kg/day) for 8 weeks dramatically reduced hepatic lipid accumulation compared to the control mice taken with HFD alone. The body and liver weights of AAE group were significantly lower than those of HFD group, and oral administration of AAE remarkably suppressed the serum levels of triglyceride (TG), total cholesterol (TC), fasting glucose, alanine transaminase (ALT) and aspartate transaminase (AST) in HFD-fed mice. AAE significantly increased the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) in the liver of HFD-fed mice and HepG2 hepatocytes. Moreover, AAE downregulated the hepatic expression of sterol regulatory element-binding protein-1c (SREBP-1c) and fatty acid synthase (FAS) in HFD-fed mice and high glucose-treated HepG2 cells. In addition, the inhibitory effects of AAE on the overexpression of SREBP-1c and FAS were attenuated by compound C, which is the specific AMPK inhibitor, in high glucose-treated HepG2 cells. These results indicated that AAE may represent a promising approach for the prevention and treatment of obesity-related NAFLD via the activation of AMPK and the regulation of AMPK-dependent lipogenic genes.

본 연구는 12주간 탄력밴드 운동이 체조성, 혈중지질 및 AMPK에 미치는 영향을 구명하기 위해 만 65세 이상 75세 이하의 여성 노인을 대상으로 운동군 12명, 대조군 12명으로 구분하여 실시하였다. 탄력밴드 운동 방법은 주 3회, 60분으로 1-4주는 OMNI-RES 3-4의 저강도, 5-8주는 OMNI-RES 5-6의 중강도, 9-12주는 OMNI-RES 7-8의 고강도로 실시하였다. 탄력밴드 운동 전·후 그룹 및 시기 간 상호작용을 검증하기 위하여 two way repeated measures ANOVA로 처리하였고, 측정된 자료의 그룹 내 차이는 paired t-test, 그룹 간 차이는 independent t-test, 집단 간 오차를 최소화하기 위해 공변량 분석 analysis of covariance ANCOVA를 실시하였으며, 각 항목별 통계적 유의수준은 .05로 설정하였다. 그 결과, 체지방률은 운동군이 유의하게 감소하였으며(p<.05), 골격근량이 유의하게 증가하였다(p<.01). 혈중지질 중 TC, TG, LDL-C는 운동군과 대조군 모두 유의한 차이가 나타나지 않았으며, HDL-C는 대조군이 유의하게 감소하였다(p<.05). AMPK는 운동군이 유의하게 감소하였고(p<.001), 대조군은 유의한 차이가 나타나지 않았으나, 공변량분석 결과에 의하면 운동 후 그룹 간 AMPK는 유의한 차이가 나타났다(p<.05). 이상의 결과를 종합해 볼 때 OMNI 저항운동 척도를 이용한 12주간 탄력밴드 운동이 여성노인의 체조성 및 AMPK에 긍정적인 영향을 미친 것으로 사료된다.

(-)-Epigallocatechin-3-gallate (EGCG) is a major catechin found in green tea. It is reported that EGCG possesses various health benefits including anti-cancer, antioxidant, anti-diabetes, and anti-obesity. The objective of this study was to investigate the effects of EGCG on adipogenesis via activation of AMP-activated protein kinase (AMPK) pathway in 3T3-L1 preadipocytes. In order to determine the effects of EGCG on adipogenesis, preadipocyte differentiation was induced in the presence or absence of EGCG (0~100 μM) for a period of 6 days. EGCG significantly inhibited fat accumulation and suppressed the expression of adipogenic specific proteins including peroxisome proliferator-activated receptor (PPAR)-γ. Also, EGCG markedly increased the activation of AMPK and acetyl-CoA carboxylase (ACC) and the production of intracellular reactive oxygen species (ROS). However, any pretreatment with a specific AMPK inhibitor, compound C, abolished the inhibitory effects of the EGCG on PPARγ expression. This study suggests that EGCG has anti-adipogenic effects through modulation of the AMPK signaling pathway and therefore, may be a promising antiobesity agent.

The effects of Ganoderma lucidum on glucose uptake was studied in L6 rat skeletal muscle cells. Glucose uptake in muscle cell was increased about 6-fold compared to control by mushroom extract treatment. This increasing effect to the glucose uptake was observed in muscle cells cultured with or without insulin. The levels of phosphor-acetyl CoA carboxylase were upregulated by G. lucidum extract treatment in insulinstimulated and basal culture conditions. However, G. lucidum extract did not affect protein kinaseB/Akt(Akt) level. Furthermore, the expression of phosphor-AMPactivated protein kinase(AMPK) was also up-regulated. AMPK is another regulatory protein in the glucose uptake pathway and energy metabolism. Thus, the treatment of G. lucidum extract in skeletal muscle cells increased the phosphorylation levels of AMPK and acetyl-CoA carboxylase, showing that the increase of glucose uptake by G. lucidum extract might be mediated via the activation of AMPK signaling pathway

Background : Non-alcoholic fatty liver disease (NAFLD) is caused by obesity, type 2 diabetes mellitus, dyslipidemia, and genetic factors. Also, hyperinsulinemia directly promotes fat accumulation in hepatocytes. Therefore, it is very important to suppress the most common risks of NAFLD, such as obesity and insulin resistance. In this context, we evaluated for the effects of black ginseng (BG) extract on lipid accumulation inhibition and degradation in hepatocytes. Methods and Results : The aim of this study is to figure out the potential anti-lipogenic effects and the underlying mechanism of BG extract in a cellular-, type 2 diabetes mellitus (T2DM) animal model associated with NAFLD. T2DM animal used C57BL/KsJ db/db mouse (M. 6 wk, n = 56), treated with extract of BG and Red ginseng (RG) (each 100 and 900 ㎎/ ㎏/day, p.o) for 6 weeks. BG markedly reduced palmitate-induced intracellular lipid accumulation in HepG2 cells. On histology of liver tissues of T2DM animal, macrovesicular lipid droplets in cytoplasm of hepatocytes were decreased both RG and BG-treated groups. In liver tissue, BG-treated groups suppressed CCAAT/enhancer binding protein-α (C/EBP-α), sterol regulatory element-binding protein-1c (SREBP-1c) expression, and SREBP-1c mediated induction of acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) proteins related to the induction of adipose differentiation. Futhermore, adenosine monophosphate (AMP)-activated protein kinase (AMPK) activity was significantly increased in BG-treated groups compared to RG-treated groups. It is also found that peroxisome proliferator-activated receptor-α (PPAR-α) highly expressed in BG-treated groups. Conclusion : Our results suggest that black ginseng extract has an anti-adipogenic and anti-lipogenic effects in the liver when administered as a food supplement and has potential as a therapeutic agent for obesity and T2DM induced NAFLD.

In the present study, we investigated the effect of 70% EtOH extract from Hippophae Rhamnoides L. leaves (HRL) on the anti-obesity effect in 3T3-L1 cells. The effects of HRL on lipid accumulation in 3T3-L1 cells were examined using Oil Red O staining. In addition, we examined the gene expression levels by using RT-PCR and western blot. The results of this analysis showed that 100 ㎍/㎖ HRL significantly increased the inhibition of lipid accumulation by 82.25%; significantly decreased the mRNA expression of sterol regulatory element binding protein-1c (SREBP-1c), peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding proteins α (C/EBPα), and fatty acid synthase (FAS) in 3T3-L1 cells as well as the stimulated protein expression of AMP-activated protein kinase (AMPK); and suppressed the expression level of PPARγ. These results suggest that HRL can prevent adipogenesis through activation of AMPKα and inhibition of adipogenesis transcription factors.