• The Korea Journal of Herbology
• /
• v.33 no.3
• /
• pp.63-70
• /
• 2018

Objective : Previous studies showed that water extract of Plantago asiatica (Plantaginis asiaticae Folium, PAF) significantly controlled in body weights, adipose tissue weights and blood lipid profiles in obese C57BL/6 mice. To investigate the mechanism of anti-obesity action of PAF, expressions of obesity-related proteins were identified such as p-AMPK and p-ACC in hypothalamus, UCP-1 in brown adipose tissue, p-AMPK, p-ACC, SREBP-1c, $PPAR{\gamma}$, HMGCR and CPT-1 in liver. Method : Five-weeks old male C57BL/6 mice were divided into 5 groups; ND (normal diet + 0.9% saline), HFD (high-fat diet + 0.9% saline), PC (high-fat diet+Garcinia cambogia 500 mg/kg), PAF 100 and 300 (high-fat diet + PAF 100 or 300 mg/kg). PAF was treated orally for 6 weeks. The protein expression of AMPK, p-AMPK, ACC, p-ACC, $PPAR{\gamma}$, SREBP-1c, HMGCR, CPT-1 and UCP-1 were identified by expression levels of proteins through western blot analysis. Result : The results showed that protein expressions on hypothalamic p-AMPK and p-ACC did not differ between the HFD and PAF groups. In addition, PAF did not affect the increase of UCP-1 in brown adipose tissue. The protein expression levels of hepatic p-AMPK, p-ACC and CPT-1 increased in PAF groups compared to HFD group. And those of $PPAR{\gamma}$, SREBP-1c and HMG-CoA decreased in PAF groups compared to HFD group. Conclusion : These results suggest that the PAF administration induce weight loss via inhibition of lipid metabolism-related protein expressions in hepatic tissues. Therefore, PAF could be used as a potent material of anti-obesity products for prevention and treatment of obesity.

• Natural Product Sciences
• /
• v.26 no.3
• /
• pp.200-206
• /
• 2020

The ability of the total extract from Physalis angulata; three fractions after partitioning with n-hexane, ethyl acetate (TBE), and water; and four withanolides (compounds 1 - 4) to phosphorylate 5'-adenosine monophosphate-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) in HepG2 cells was evaluated. The TBE fraction (50 ㎍/mL) activated p-ACC and p-AMPK expression most strongly. Compounds 1 - 4 (10 μM) upregulated p-ACC expression at different levels. Compound 4 induced the most significant changes in p-AMPK expression, followed by 1 and 2. Sterol regulatory element-binding proteins (SREBPs) play a functional role in the transcriptional regulation of the lipogenic pathway, including fatty acid synthase (FAS) and ACC. The effects of compounds 2 and 4 (10 μM) on FAS and SREBP-1c expression under high glucose conditions (30 mM) in HepG2 cells were evaluated further. Both dose-dependently inhibited FAS and SREBP-1c expression as well as lipid accumulation (1 - 10 μM) were compared to high-concentration glucose control, which upregulated FAS and SREBP-1c. These results suggest that compounds 2 and 4 upregulate AMPK, suppress FAS and SREBP-1c, and have potential effects on glucose and lipid metabolism.

• Journal of Ginseng Research
• /
• v.38 no.1
• /
• pp.16-21
• /
• 2014

Ginseng saponins exert various important pharmacological effects with regard to the control of many diseases, including cancer. In this study, the anticancer effect of ginsenosides on human cancer cells was investigated and compared. Among the tested compounds, ginsenoside-Rh2 displays the highest inhibitory effect on cell viability in HepG2 cells. Ginsenoside-Rh2, a ginseng saponin isolated from the root of Panax ginseng, has been suggested to have potential as an anticancer agent, but the underlying mechanisms remain elusive. In the present study, we have shown that cancer cells have differential sensitivity to ginsenoside-Rh2-induced apoptosis, raising questions regarding the specific mechanisms responsible for the discrepant sensitivity to ginsenoside-Rh2. In this study, we demonstrate that AMP-activated protein kinase (AMPK) is a survival factor under ginsenoside-Rh2 treatment in cancer cells. Cancer cells with acute responsiveness of AMPK display a relative resistance to ginsenoside-Rh2, but cotreatment with AMPK inhibitor resulted in a marked increase of ginsenoside-Rh2-induced apoptosis. We also observed that p38 MAPK (mitogen-activated protein kinase) acts as another survival factor under ginsenoside-Rh2 treatment, but there was no signaling crosstalk between AMPK and p38 MAPK, suggesting that combination with inhibitor of AMPK or p38 MAPK can augment the anticancer potential of ginsenoside Rh2.

• Journal of Animal Science and Technology
• /
• v.54 no.5
• /
• pp.369-373
• /
• 2012

AMP-activated protein kinase (AMPK) maintains energy homeostasis in skeletal muscle. Nonetheless, its functional role on protein synthesis with different nutrient availability has not been elucidated. Therefore, the purpose of this study is to examine the effect of AMPK activity on protein content in C2C12 myotubes incubated with low (5 mM; LG) or high (25 mM; HG) glucose media. LG stimulated (p<0.05) AMPK and acetyl CoA carboxylase (ACC) activity compare to those in HG group. Total protein content was higher in myotubes cultured with HG than in those cultured with LG and further increased by AICAR (5-amino-1-${\beta}$-D-ribofuranosyl-imidazole-4-carboxamide). Myotubes cultured with HG showed 7.5% lower UbFL (Ubiquitin Firefly Luciferase)-to-SV40 (Simian virus40) ratio compared to those in LG. Glucose level did not change the phosphorylation level of mammalian target of rapamycin (mTOR). Interestingly, administration of AICAR significantly increased phosphorylation level of mTOR in myotubes cultured with LG but not in those with HG. Overall, this data indicate that AMPK activity and protein turnover are finely regulated in response to different glucose concentration.

• The Korea Journal of Herbology
• /
• v.22 no.2
• /
• pp.155-161
• /
• 2007

Objectives: Evidences suggests that Ginkgo biloba, a widely used traditional medicine, shows a hypoglycemic effect. Thus, we investigatd the effect of G. biloba extract (GB) on glucose uptake in L6 rat skeletal muscle cells. Method : Effect of GB on glucose uptake and phosphatidylinositol (PI) 3-kinase activity were assessed using Glucose uptake assay and PI 3-kinase assay, respectively. Also, AMP-activated protein kinase (AMPK), p38 mitogen activated protein kinase (p38 MAPK) expression were identified by Western blot. Results : Glucose uptake assay revealed that GB increased glucose uptake about 2.5-fold compared to thecontrol. GB stimulated the activity of PI 3-kinase which is a major switch element on the glucose uptake pathway. About a 6.5-fold increase in activity of PI 3-kinase was observed with GB. We then assessed the activity of AMPK, another regulatory molecule on the glucose uptake pathway. The result was that GB increased the phosphorylation level of both AMPK ${\alpha}$l and ${\alpha}$2. The activity of p38 MAPK, a downstream mediator of AMPK, was also increased by CB. Conclusion : These results suggest that GB may stimulate glucose uptake through both PI 3-kinase and AMPK mediated pathways in L6 skeletal muscle cells thereby contributing to glucose homeostasis.

• Journal of Korean Medicine for Obesity Research
• /
• v.14 no.1
• /
• pp.13-23
• /
• 2014

Objectives: This study was performed to evaluate the effects of Metformin and Lonicerae Flos, Agrobacterium Rhizogenes, Coptidis Rhizoma, Atractylodis Rhizoma Alba, Houttuyniae Herba extracs combinations on hypoglycemia in RAW 264.7 cells. Methods: Expressions of Sirt1, p-adenosine monophosphate-activated kinase (p-AMPK), AMPK-alpha, peroxisome proliferator activated receptor (PPAR)-alpha, PPAR-gamma, X-box binding protein 1 (XBP-1), tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 were analyzed by real time polymerase chain reaction and Western blotting analysis. Results: The level of gene expression of Sirt1, p-AMPK, AMPK-alpha, PPAR-alpha and XBP-1 in relation to that of beta-actin were increased or decreased significantly with the Metformin and Lonicerae Flos, Agrobacterium Rhizogenes extracts combination groups. The level of gene expression of TNF-alpha and IL-6 were increased significantly with the Metformin and Houttuyniae Herba, Coptidis Rhizoma extracts combination groups. Conclusions: Metformin and Lonicerae Flos, Agrobacterium Rhizogenes extracts combination groups showed synergistic hypoglycemic effects by increasing AMPK and PPAR gene expression in RAW 264.7 cells.

• Korean Journal of Plant Resources
• /
• v.37 no.3
• /
• pp.247-255
• /
• 2024

In this study, we aimed to verify the anti-obesity activity of R. acicularis leaves (RAL) and elucidate its mechanism of action in 3T3-L1 preadipocytes. RAL dose-dependently inhibited the accumulation of lipid droplets and triacylglycerol. RAL did not affect cell proliferation and survival in undifferentiated 3T3-L1 cells, but it inhibited cell proliferation in differentiating 3T3-L1 cells. RAL increased ATGL, p-HSL, and HSL, and decreased perilipin-1 in differentiating 3T3-L1 cells. In addition, RAL reduced lipid droplet accumulation and increased free glycerol content in differentiated 3T3-L1 cells. RAL increased ATGL and HSL in differentiated 3T3-L1 cells. Also, RAL increased p-AMPK, PPARγ, UCP-1, and PGC-1α in differentiating 3T3-L1 cells. AMPK inhibition by compound C attenuated RAL-mediated increase of ATGL, HSL, PPARγ, and UCP-1 in 3T3-L1 cells. Taken together, it is thought that RAL may inhibit lipid accumulation through lipolysis and thermogenesis via the activation of AMPK in adipocytes.

• BMB Reports
• /
• v.53 no.5
• /
• pp.272-277
• /
• 2020

Protein kinase CK2 downregulation induces premature senescence in various human cell types via activation of the reactive oxygen species (ROS)-p53-p21^Cip1/WAF1 pathway. The transcription factor "nuclear factor erythroid 2-related factor 2" (Nrf2) plays an important role in maintaining intracellular redox homeostasis. In this study, Nrf2 overexpression attenuated CK2 downregulation-induced ROS production and senescence markers including SA-β-gal staining and activation of p53-p21^Cip1/WAF1 in human breast (MCF-7) and colon (HCT116) cancer cells. CK2 downregulation reduced the transcription of Nrf2 target genes, such as glutathione S-transferase, glutathione peroxidase 2, and glutathione reductase 1. Furthermore, CK2 downregulation destabilized Nrf2 protein via inhibiting autophagic degradation of Kelch-like ECH-associated protein 1 (Keap1). Finally, CK2 downregulation decreased the nuclear import of Nrf2 by deactivating AMP-activated protein kinase (AMPK). Collectively, our data suggest that both Keap1 stabilization and AMPK inactivation are associated with decreased activity of Nrf2 in CK2 downregulation-induced cellular senescence.

• The Korea Journal of Herbology
• /
• v.37 no.2
• /
• pp.1-11
• /
• 2022

Objectives : Although the anti-obesity effect of Schizandrae Fructus water extract has been demonstrated, its underlying mechanism is still unclear. Therefore, we aimed to evaluate the anti-obesity effect of Schizandrae Fructus water extract through the p-AMP-activated protein kinase (p-AMPK), sirtuin1 (Sirt1), and peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC-1α) signaling in 60% high-fat diet (HFD)-induced obese mouse model. Methods : Male C57BL/6 mice were divided into four groups. The Normal group was fed a normal diet and the obese groups were fed 60% HFD. Except for the Control group, the GG group was supplemented with 0.5% Garcinia gummigutta and the SCW group was supplemented with 0.5% Schizandrae Fructus water extract. After 6 weeks, obesity-related biomarkers in serum were measured and the expressions of protein for lipid-related factors in liver tissue were analyzed by western blot. Results : Treatment with SCW significantly down-regulated body weight compared to the Control group. SCW down-regulated levels of triglyceride and total cholesterol in serum and significantly increased p-AMPK, Sirt1, and PGC-1α in liver tissue. In addition, the expressions of fatty acid oxidation-related proteins such as peroxisome proliferator-activated receptor α (PPARα), carnitine palmitoyltransferase 1A (CPT-1A), uncoupling protein 1 (UCP1), and uncoupling protein 3 (UCP3) were significantly up-regulated. However, fatty acid synthesis-related proteins including sterol regulatory element-binding protein-1 (SREBP-1), phospho-Acetyl-CoA Carboxylase (p-ACC), and fatty acid synthase (FAS) were significantly down-regulated. Conclusions : Taken together, SCW treatment showed anti-obesity effect by regulating both fatty acid oxidation-related and fatty acid synthesis-related proteins through AMPK/Sirt1/PGC-1α signaling in 60% HFD-induced obese mice.

• Nutrition Research and Practice
• /
• v.14 no.5
• /
• pp.478-489
• /
• 2020

BACKGROUND/OBJECTIVES: Morusin, a marker component of Morus alba L., possesses anti-cancer activity. The objective of this study was to determine autophagy-inducing effect of morusin in non-small cell lung cancer (NSCLC) cells and investigate the underlying mechanism. SUBJECTS/METHODS: Autophagy induction and the expression of autophagy-related proteins were analyzed by LC3 immunofluorescence and western blot, respectively. The role of autophagy and AMP-activated protein kinase (AMPK) was determined by treating NSCLC cells with bafilomycin A1, an autophagy inhibitor, and compound C, an AMPK inhibitor. Cytotoxicity and apoptosis induction were determined by MTT assay, trypan blue exclusion assay, annexin V-propidium iodide (PI) double staining assay, and cell cycle analysis. RESULTS: Morusin increased the formation of LC3 puncta in the cytoplasm and upregulated the expression of autophagy-related 5 (Atg5), Atg12, beclin-1, and LC3II in NSCLC cells, demonstrating that morusin could induce autophagy. Treatment with bafilomycin A1 markedly reduced cell viability but increased proportions of sub-G1 phase cells and annexin V-positive cells in H460 cells. These results indicate that morusin can trigger autophagy in NSCLC cells as a defense mechanism against morusin-induced apoptosis. Furthermore, we found that AMPK and its downstream acetyl-CoA carboxylase (ACC) were phosphorylated, while mammalian target of rapamycin (mTOR) and its downstream p70S6 kinase (p70S6K) were dephosphorylated by morusin. Morusin-induced apoptosis was significantly increased by treatment with compound C in H460 cells. These results suggest that morusin-induced AMPK activation could protect NSCLC cells from apoptosis probably by inducing autophagy. CONCLUSIONS: Our findings suggest that combination treatment with morusin and autophagy inhibitor or AMPK inhibitor might enhance the clinical efficacy of morusin for NSCLC.