• Molecular & Cellular Toxicology
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• 제4권3호
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• pp.224-229
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• 2008

Eucommia ulmoides (Duchung) is commonly used for treatment of diabetes in Korean traditional medicine. However, the exact mechanism of its anti-diabetic effect has not yet been fully elucidated. In this study, the effect of E. ulmoides extract on glucose uptake was investigated in L6 rat skeletal muscle cells. E. ulmoides extract stimulated the activity of phosphatidylinositol (PI) 3-kinase that is a major regulatory molecule in glucose uptake pathway. Protein kinase B (PKB) and protein kinase C-${\xi}$ (PKC-${\xi}$), downstream mediators of PI 3-kinase, were also activated by E. ulmoides extract. We assessed the activity of AMP-activated protein kinase (AMPK), another regulatory molecule in glucose uptake pathway. Phosphorylation level of AMPK did not change with treatment of E. ulmoides extract. Phosphorylations of p38 mitogen activated protein kinase (p38 MAPK) and acetyl-CoA carboxylase (ACC), downstream mediators of AMPK, were not significantly different. Taken together, our results suggest that E. ulmoides may stimulate glucose uptake through PI 3-kinase but not AMPK in L6 skeletal muscle cells.

• Natural Product Sciences
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• 제26권3호
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• pp.200-206
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• 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.

• 대한한방내과학회지
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• 제39권3호
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• pp.302-312
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• 2018

Objectives: This study was performed to investigate the effects of two herbal medicines, Agastachis Herba and Lysimachiae Herba, on a cellular model of non-alcoholic fatty liver diseases (NFLDs). Methods: HepG2 cells were treated with palmitic acid and with various concentrations of Agastachis Herba (AH) or Lysimachiae Herba (LH) extract in water. The lipotoxicity was assessed using EZ-cytox, and the lipoapoptosis was assessed using cell death detection ELISA. Intracellular lipids were measured by oil red O staining. The efficacy of AH and LH on sterol regulatory element-binding transcription factor-1c (SREBP-1c), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC) in HepG2 cells was measured by reverse transcription polymerase chain reaction (RT-PCR). Results: Both AH and LH extracts increased lipoapoptosis and decreased lipotoxicity and levels of SREBP-1c, ACC, and FAS (SREBP-1c, ACC, and FAS are factors in lipid synthesis). In the oil red O staining experiment, both extracts also reduced intracellular lipid accumulation; in this instance, LH's efficacy was superior to that of AH. Conclusions: According to the results, both AH and LH are likely to contribute to non-alcoholic fatty liver disease, as both interfere with lipid synthesis.

• The Korean Journal of Physiology and Pharmacology
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• 제21권3호
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• pp.279-286
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• 2017

The root bark extract of Aralia taibaiensis is used traditionally for the treatment of diabetes mellitus in China. The total saponin extracted from Aralia Taibaiensis (sAT) has effective combined antihyperglycemic and hypolipidemic activities in experimental type 2 diabetic rats. However, the active compounds have not yet been fully investigated. In the present study, we examined effects of twelve triterpenoid saponins on AMP-activated protein kinase (AMPK) activation, and found that compound 28-O-${\beta}$-D-glucopyranosyl ester (AT12) significantly increased phosphorylation of AMPK and Acetyl-CoA carboxylase (ACC). AT12 effectively decreased blood glucose, triglyceride (TG), free fatty acid (FFA) and low density lipoprotein-cholesterol (LDL-C) levels in the rat model of type 2 diabetes mellitus (T2DM). The mechanism by which AT12 activated AMPK was subsequently investigated. Intracellular ATP level and oxygen consumption were significantly reduced by AT12 treatment. The findings suggested AT12 was a novel AMPK activator, and could be useful for the treatment of metabolic diseases.

• 대한본초학회지
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• 제30권4호
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• pp.21-27
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• 2015

Objectives : In this study, we investigated the biological activities such as anti-obesity using Samwondan ethanol extract (SWD). SWD is a complex with Salicornia herbacea Linnaeus, Saururus chinensis Baill and Houttuynia cordata Thunberg as the main raw material.Methods : The SWD was extracted 80% ethanol. 3T3-L1 preadipocytes were induced adipogenesis by differentiation media with SWD at 1 μg/mL, 10 μg/mL, and 100 μg/mL. Effect of SWD performed using MTT assay, oil red O staining (observation by microscope), and reverse transcription polymerase chain reaction. Also we measured production of triglyceride (TG), fatty acid, and acetyl-CoA carboxylase (ACC).Results : Non-cytotoxicity was in all test group from range of 1 μg/mL to 100 μg/mL on pre-adipocyte. The droplet and production of lipid were decreased significantly by the SWD. And TG was decreased by approximately 89%, 85% and 82%, upon the SWD treatment at concentration of 1 μg/mL, 10 μg/mL, and 100 μg/mL. Moreover, the SWD showed inhibitory effects on the expression of the C/EBP (CCAAT/enhaner binding protein)β, C/EBPα, and peroxisome proliferator-activated receptorγgenes in adipocytes. The SWD at 100 μg/mL concentration showed inhibitory effect on fatty acid production by 79%. Also ACC production were decreased dose-dependently.Conclusions : From the results above, we concluded that the SWD indicated significantly anti-obesity effects.

• Asian-Australasian Journal of Animal Sciences
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• 제25권8호
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• pp.1145-1152
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• 2012

This experiment was conducted with male chicks to investigate the influence of hormones and nutrients on the development of fatty liver syndrome (FLS) as well as the effects of dietary lipotropic factors on hepatic fat accumulation and lipogenic enzyme gene expression. A total of two-hundred sixteen 4-wk-old Hy-Line male chicks were divided into six groups and fed an experimental diet (T1, low-energy diet with low levels of lipotropic factors; T2, high-energy diet with low levels of lipotropic factors; T3 and T5, low-energy diet with high levels of lipotropic factors; T4 and T6, high-energy diet with high levels of lipotropic factors) for six weeks. The chicks in T5 and T6 groups were treated with intramuscular injections of estradiol benzoate for three days prior to biopsy and clinical analysis of FLS. Chicks treated with estrogen had significantly greater liver weights than untreated chicks. The abdominal fat contents were increased in chicks consuming high-energy diets as compared to those consuming low-energy diets. Treatment with estrogen significantly increased the concentrations of serum cholesterol, triacylglycerol and phospholipid (p<0.05). The hepatic triacylglycerol levels were tenfold higher in the estrogen treated chicks than in the untreated chicks. There were no significant differences in malondialdehyde levels between the treatment groups. Estrogen treatment dramatically increased the levels of fatty acid synthetase, acetyl-CoA carboxylase and ApoB mRNA. The results indicated that treatment with exogenous estrogen in growing male chicks induced hepatic fat accumulation, which might be partially due to increased lipogenic enzyme gene expression.

• Asian-Australasian Journal of Animal Sciences
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• 제19권3호
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• pp.412-417
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• 2006

This study evaluated the effectiveness of different arsenical sources on inducing fatty liver, on changes in lipid metabolism and on liver function in mule ducks. Sixty twelve-week-old mule ducks were selected and randomly divided into five treatments, including the control group and four different arsenical sources; Roxarsone (300 mg/kg), arsanilic acid, $As_2O_5$ or $As_2O_3$, containing 85.2 mg/kg arsenic were included in the basal diet. The ducks were fed the medicated basal diet for 3 weeks followed by a one-week drug withdrawal. The results showed Roxarsone treatment decreased body weight, feed intake, liver weight and abdominal fat weight (p<0.05), while it increased the relative liver weight (p<0.05) during medication period ($3^{rd}$ week). The $As_2O_5$ treatment decreased abdominal fat weight and relative abdominal fat weight when compared to the control (p<0.05). Only Roxarsone among the treatment groups increased feed intake, liver weight and relative liver weight, while the $As_2O_3$ group showed the lightest liver weight and relative liver weight among treatment groups during the withdrawal period ($4^{th}$ week). The Roxarsone group decreased (p<0.05) NADP-malic dehydrogenase (MDH) and acetyl-CoA carboxylase (ACC) activities and increased (p<0.05) cholesterol concentration during the medication period, and elevated the MDH and ACC activities during the withdrawal period. All four arsenical treatment groups showed lymphocytic infiltration in liver tissue, while the Roxarsone and $As_2O_3$ treatments showed an increase in aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) activities (p<0.05). During the withdrawal period, arsenical treatments resulted in liver vacuoles. However, the arsenicals differed in effectiveness and mechanisms of inducing fat vacuoles.

• 대한한의학방제학회지
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• 제24권2호
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• pp.100-107
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• 2016

Objectives : The purpose of this study is to evaluate the anti-lipogenic effect of Sobuncheong-eum on non-alcoholic fatty liver disease in free fatty acid induced cellular model. Methods : HepG2 cells were treated with palmitate for 24h to overload intracellular triglyceride (TG) content in the presence or absence of Sobuncheong-eum extract. After palmitate treatment, Intracellular TG content was measured with TG assay kit. Several lipogenesis related markers, including AMP-activated protein kinase (AMPK), sterol regulatory element-binding transcription factor-1c (SREBP-1c), acetyl-CoA carboxylase (ACC), and fatty acid synthase (FAS), were assessed using Western-blot analyses and RT-PCR. Results : Palmitate markedly increased intracellular TG in HepG2 cells, and which were alleviated by coadministered Sobuncheong-eum extract. Sobuncheong-eum extract activated AMPK, which plays a key role in reducing hepatic lipid accumulation, and reduced lipogenic fators, SREBP-1c, ACC, and FAS. Conclusions : Taken together, it is conceivable that Sobuncheong-eum has an potential to alleviate steatosis, and which may be mediated by activating AMPK at least in part.

• Journal of Microbiology and Biotechnology
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• 제21권9호
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• pp.921-929
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• 2011

Stimulation of AMP-activated protein kinase (AMPK) signaling followed by increase of glucose uptake in L6 myotubes were studied with organic solvent extract of Malva verticillata (MV) seeds. Ethanol extract of M. verticillata seeds (MVE) significantly increased the phosphorylation level of AMPK, acetyl-CoA carboxylase (ACC), and glucose uptake in L6 myotube cells. The MVE was fractionated with n-hexane (MVE-H), chloroform (MVE-C), ethylacetate (MVE-E), n-butanol (MVE-B), and water (MVE-W). MVE-H (150 ${\mu}g$/ml) showed the highest phosphorylating activity and increased glucose uptake by 2.3-fold. Oral administration of MVE-H (40 mg/kg) for 4 weeks to type 2 diabetic (db/db) mice reduced non-fasting and fasting blood glucose levels by 17.1% and 23.3%, respectively. Phosphorylation levels of AMPK and ACC in the soleus muscle and liver tissue of db/db mice were significantly increased by the administration of MVE-H. MVE-H was further fractionated using preparative HPLC to identify the AMPK-activating compounds. The NMR and GC-MS analyses revealed that ${\beta}$-sitosterol was a major effective compound in MVE-H. Phosphorylation levels of AMPK and ACC, and glucose uptake were significantly increased by the treatment of MVE-S (${\beta}$-sitosterol) isolated from M. verticillata to L6 cells, and these effects were attenuated by an AMPK inhibitor (Compound C) pretreatment. These results, taken together, demonstrate that increased glucose uptake in L6 myotubes by MVE-H treatment is mainly accomplished through the activation of AMPK. Our finding suggests that the extract isolated from M. verticillata seed would be beneficial for the treatment of metabolic disease including type 2 diabetes and hyperlipidemia.

• 대한본초학회지
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• 제34권6호
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• pp.99-107
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• 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.