• Biomolecules & Therapeutics
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• 제25권5호
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• pp.504-510
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• 2017

Inhibitor of nuclear factor kappa-B kinase beta ($IKK{\beta}$) plays a critical role in cell proliferation and inflammation in various cells by activating $NF-{\kappa}B$ signaling. However, the interrelationship between peroxisome proliferator-activated receptor ${\alpha}$ ($PPAR{\alpha}$) and $IKK{\beta}$ in cell proliferation is not clear. In this study, we investigated the possible role of $PPAR{\alpha}$ in the hepatic cell death in the absence of $IKK{\beta}$ gene using liver-specific Ikkb-null ($Ikkb^{F/F-AlbCre}$) mice. To examine the function of $PPAR{\alpha}$ activation in hepatic cell death, wild-type ($Ikkb^{F/F}$) and $Ikkb^{F/F-AlbCre}$ mice were treated with $PPAR{\alpha}$ agonist Wy-14,643 (0.1% w/w chow diet) for two weeks. As a result of Wy-14,643 treatment, apoptotic markers including caspase-3 cleavage, poly (ADP-ribose) polymerase (PARP) cleavage and TUNEL-positive staining were significantly decreased in the $Ikkb^{F/F-AlbCre}$ mice. Surprisingly, Wy-14,643 increased the phosphorylation of p65 and STAT3 in both Ikkb and $Ikkb^{F/F-AlbCre}$ mice. Furthermore, BrdU-positive cells were significantly increased in both groups after treatment with Wy-14,643. Our results suggested that $IKK{\beta}-derived$ hepatic apoptosis could be altered by $PPAR{\alpha}$ activation in conjunction with activation of $NF-{\kappa}B$ and STAT3 signaling.

• Journal of Microbiology and Biotechnology
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• 제23권11호
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• pp.1569-1576
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• 2013

In mice, supplementation of t10,c12 conjugated linoleic acid (CLA) increases liver mass and hepatic steatosis via increasing uptake of fatty acids released from adipose tissues. However, the effects of t10,c12 CLA on hepatic lipid synthesis and the associated mechanisms are largely unknown. Thus, we tested the hypothesis that gut microbiota-producing t10,c12 CLA would induce de novo lipogenesis and triglyceride (TG) synthesis in HepG2 cells, promoting lipid accumulation. It was found that treatment with t10,c12 CLA ($100{\mu}M$) for 72 h increased neutral lipid accumulation via enhanced incorporation of acetate, palmitate, oleate, and 2-deoxyglucose into TG. Furthermore, treatment with t10,c12 CLA led to increased mRNA expression and protein levels of lipogenic genes including SREBP1, ACC1, FASN, ELOVL6, GPAT1, and DGAT1, presenting potential mechanisms by which CLA may increase lipid deposition. Most strikingly, t10,c12 CLA treatment for 3 h increased phosphorylation of mTOR, S6K, and S6. Taken together, gut microbiota-producing t10,c12 CLA activates hepatic de novo lipogenesis and TG synthesis through activation of the mTOR/SREBP1 pathway, with consequent lipid accumulation in HepG2 cells.

• The Korean Journal of Physiology and Pharmacology
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• 제22권1호
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• pp.23-33
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• 2018

Cushing's syndrome (CS) is a collection of symptoms caused by prolonged exposure to excess cortisol. Chronically elevated glucocorticoid (GC) levels contribute to hepatic steatosis. We hypothesized that histone deacetylase inhibitors (HDACi) could attenuate hepatic steatosis through glucocorticoid receptor (GR) acetylation in experimental CS. To induce CS, we administered adrenocorticotropic hormone (ACTH; 40 ng/kg/day) to Sprague-Dawley rats by subcutaneous infusion with osmotic mini-pumps. We administered the HDACi, sodium valproate (VPA; 0.71% w/v), in the drinking water. Treatment with the HDACi decreased steatosis and the expression of lipogenic genes in the livers of CS rats. The enrichment of GR at the promoters of the lipogenic genes, such as acetyl-CoA carboxylase (Acc), fatty acid synthase (Fasn), and sterol regulatory element binding protein 1c (Srebp1c), was markedly decreased by VPA. Pan-HDACi and an HDAC class I-specific inhibitor, but not an HDAC class II a-specific inhibitor, attenuated dexamethasone (DEX)-induced lipogenesis in HepG2 cells. The transcriptional activity of Fasn was decreased by pretreatment with VPA. In addition, pretreatment with VPA decreased DEX-induced binding of GR to the glucocorticoid response element (GRE). Treatment with VPA increased the acetylation of GR in ACTH-infused rats and DEX-induced HepG2 cells. Taken together, these results indicate that HDAC inhibition attenuates hepatic steatosis through GR acetylation in experimental CS.

• Journal of Ginseng Research
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• 제42권4호
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• pp.419-428
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• 2018

Background: Despite the large number of studies on ginseng, pharmacological activities of ginseng seed oil (GSO) have not been established. GSO is rich in unsaturated fatty acids, mostly oleic and linoleic acids. Unsaturated fatty acids are known to exert a therapeutic effect in nonalcoholic fatty liver disease (NAFLD). In this study, we investigated the protective effect and underlying mechanisms of GSO against NAFLD using in vitro and in vivo models. Methods: In vitro lipid accumulation was induced by free fatty acid mixture in HepG2 cells and by 3 wk of high fat diet (HFD)-feeding in Sprague-Dawley rats prior to hepatocyte isolation. The effects of GSO against diet-induced hepatic steatosis were further examined in C57BL/6J mice fed a HFD for 12 wk. Results: Oil Red O staining and intracellular triglyceride levels showed marked accumulation of lipid droplets in both HepG2 cells and rat hepatocytes, and these were attenuated by GSO treatment. In HFD-fed mice, GSO improved HFD-induced dyslipidemia and hepatic insulin resistance. Increased hepatic lipid contents were observed in HFD-fed mice and it was lowered in GSO (500 mg/kg)-treated mice by 26.4% which was evident in histological analysis. Pathway analysis of hepatic global gene expression indicated that GSO increased the expression of genes associated with ${\beta}$-oxidation (Ppara, Ppargc1a, Sirt1, and Cpt1a) and decreased the expression of lipogenic genes (Srebf1 and Mlxipl), and these were confirmed with reverse transcription and quantitative polymerase-chain reaction. Conclusion: These findings suggest that GSO has a beneficial effect on NAFLD through the suppression of lipogenesis and stimulation of fatty acid degradation pathway.

• 대한생식의학회:학술대회논문집
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• 대한생식의학회 2007년도 제52차 춘계학술대회 초록집
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• pp.9-10
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• 2007

• 대한임상검사과학회지
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• 제47권4호
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• pp.251-258
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• 2015

커큐민(curcumin)은 강황 내 주요 폴리페놀 화합물의 한 성분으로 비만과 관련된 비알코올성 지방간염을 막아 주는 것으로 잘 알려져 있다. 이 연구의 목적은 고지방 식이로 키운 비만 마우스에서 사염화탄소($CCl_4$)로 유발한 간섬유증에 미치는 커큐민의 보호효과를 조사하기 위해 시도하였다. 군간 비교를 위해, 정상 식이와 고지방 식이로 키운 마우스에 7주간 $CCl_4$를 투여하면서 동시에 커큐민을 투여한 것과 투여하지 않은 군으로 나누었으며, 체중이나 혈당과 같은 대사 프로파일이나 지방세포의 크기 및 간섬유증의 변화를 조사하기 위해 혈청 생화학적 검사, 조직학적 검사 및 면역조직화학적 검사를 수행하였다. 또한 간세포 내자멸세포의 관찰을 위해 TUNEL 법을 사용하였다. 그 결과 고지방식이+$CCl_4$ 마우스에 커큐민을 투여한 군에서는 투여하지 않은 군에 비해 체중, 공복혈당 수치, 혈청 AST, ALT 수치가 낮았고, 지방조직 내의 지방세포 크기와 대식세포 및 비만세포 수가 감소하였다. 이와 반대로 정상식이+$CCl_4$ 마우스에 커큐민을 투여한 경우에는 투여하지 않은 군에 비해 체중과 비만세포 수 이외에는 통계학적인 차이가 없었다. 더욱이 커큐민은 간조직의 간실질세포의 자멸세포 수는 줄인 반면 활성 간성상세포 모양의 비실질세포의 자멸세포 수를 증가시켰다. 이 결과를 종합해 볼 때 커큐민은 비만 마우스의 간질환 진행에서 효과적인 항섬유 치료제로서 사용할 수 있을 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제14권5호
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• pp.891-900
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• 2004

UDP-N-Acetylglucosamine(GlcNAc):$\beta$1,4-D-mannoside$\beta$-l ,4N-acetylglucosaminyltransferase-III (GnT-III) and UDP-N-GlcNAc:$\alpha$-6-D-mannosid$\beta$-1,6N-acetylglucosaminyltransferase-V(GnT - V) activities were determined in human hepatoma cell lines and metastatic colon cancer cells, and their activities were compared with those of normal liver cells and fetal hepatocytes. GnT-III activities were higher than those of GnT-V in hepatic carcinoma cells. When the two enzyme activities were assayed in highly metastatic colon cancer cells, GnT - V activities were much higher than those of GnT-III. When GlcN, GlcN-biant-PA and UDP-GlcNAc were used as substrates, the enzymes displayed different kinetic properties between hepatic and colon cancer cells, depending on their metastatic potentials. Normal cells of two origins had characteristically very low levels of GnT-III and -V activities, whereas hepatoma and colon cancer cells contained high levels of activities. These data were supported by RT-PCR and Northern blot analyses, showing that the expression of GnT-III and -V mRNAs were increased in proportion to the enzymatic activities. The increased GnT-III, md -V activities were also correlated with increased glycosylation of the cellular glycoproteins in hepatoma and colon cancer cells, as examined by lectin blotting analysis by using wheat germ glutinin (WGA), erythroagglutinating phytohemagglutinin (E-PHA), leukoagglutinating phytohemagglutinin (L-PHA), and concanavalin A (Con A). Treatment with retinoic acid, a differentiation agent, resulted in decreases of both GnT-III and -V activities of HepG2 and HepG3 cells. In colon carcinoma cells, however, treatment with retinoic acid resulted in a reduction of GnT-V activity, but not with GnT-III activity. Although the mechanism underlying the induction of these mzymes is unclear, oligosaccharides in many glycoproteins have been observed of cancer cells.

• 대한약침학회지
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• 제13권2호
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• pp.13-31
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• 2010

Objective : Bujeonghangam-tang(BH) has been used for cure of tumor as a traditional medicine. This study was carried out to clarify the effect of BH extract on hepatocellular carcinogenesis and hepatic cirrhosis induced by Diethylnitrosamine(DENA) and $CCl_4$ in Rats. Method : Experimental groups were divided into two, 8th and 12th week groups, and subdivided into four; normal group(Nor), cirrhosis and hepatic cancer inducing control group(Con), and BH extract 320 mg/kg/day(BHA) or 640 mg/kg/day(BHB) administered groups to Con. Results: In the 8th week group: The body weight decreased significantly in Con compared with the Nor. The activities of transaminase, alkaline phosphatase(ALP), and lactacte dehydrogenase(LDH) were significantly increased(p<0.05) in the Con compared with Nor, but decreased in the BHA and BHB compared with Con. Alpha fetoprotein(AFP) were the most increased in the Con compared to BHA and BHB. The results of light microscopical observation, a number of hepatocytes were damaged in the Con compared with Nor and BH extract administerd groups. The number of hepatic p53 positive cells was reduced in the BH extract administered groups. According to the electron microscopical observation, hepatocarcinoma cells were observed distinctly in the Con compared with BH extract administered groups. In the 12 weeks group: The results of body were similar to 8th week groups. The activities of transaminase and ALT were significantly increased(p<0.05) in the Con compared with Nor. LDH was significantly(p<0.05) increased in the Con compared with Nor but significantly (p<0.05) decreased in the BHB. Alpha fetoprotein(AFP) were the most increased in the Con among ex perimental groups. The activities of superoxide dismutase(SOD) were significantly (p<0.05) increased in the Con, but the activities of catalase were not increased(p<0.05) compared with Nor. The number of hepatic p53 positive cells was increased in the Con. The results of electron microscopical observation were similar to 8th week groups. Conclusion : These results suggest that ad ministration of BH extract suppress or retard DENA and $CCl_4$-induced hepatocellular carcinogenesis and hepatic cirrhosis in rats.

• 생약학회지
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• 제44권2호
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• pp.110-117
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• 2013

Cirsium japonicum (CJ) leaf (L) alcoholic extracts were investigated for analysis their active components (flavonoids and flavanolignans; silymarins) and inhibitory effect on transforming growth factor (TGF)-${\beta}$ induced hepatic stellate cells (HSCs, LX-2 cells) activation. The CJ root (R) extracts were also analyzed and compared with leaf extracts. Total flavonoid and polyphenol contents of the leaf extracts showed higher than those of the root extracts. The content of each flavonoid compound, which was analyzed by HPLC, in CJ-L extracts was also higher than in CJ-R extracts. The results of flavanolignans content in CJ-L and CJ-R extracts were consistent in flavonoid and polyphenol. We studied inhibitory effect of two extracts against TGF-${\beta}1$ induced HSCs activation. The CJ-L extracts significantly suppressed overexpression of profibrogenic factor, ${\alpha}$-smooth muscle actin and collagen-${\alpha}1$(I). The CJ-R extract also showed inhibitory effect on TGF-${\beta}1$ induced HSCs activation, but the efficacy was lower than in CJ-L extract. These results suggest that CJ-L may contribute to the fibrotic liver treatment.

• Biomolecules & Therapeutics
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• 제30권2호
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• pp.162-169
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• 2022

We utilized Fas21, a resveratrol analog, to modulate the function of hepatic stellate cells (HSCs) and liver sinusoidal endothelial cells (LSECs) during the angiogenic phase of murine liver metastasis by B16 melanoma and 51b colorectal carcinoma. Preangiogenic micrometastases were treated with Fas21 (1 mg/kg/day) or vehicle during the development of intra-angiogenic tracts. Mice treated with Fas21 showed reduced liver tumor foci in both liver metastasis models. Micrometastases were classified immunohistochemically, as well as according to their position coordinates and connection to local microvasculature. The volume of liver occupied by sinusoidal-type foci, containing infiltrating angiogenic capillaries, decreased by ~50% in Fas21-treated mice compared to vehicle-treated ones in both tumor metastasis models. The volume of portal foci, containing peripheral neoangiogenesis within a discontinuous layer of myofibroblasts, was similar in all experimental groups in both tumor metastasis models, but displayed enhanced necrotic central areas devoid of angiogenesis following Fas21 treatment. As a result, sinusoidal tumors from mice treated with Fas21 showed a 50% reduction in desmin(+)/asma(+) HSCs and CD31(+) vessel density, and a 45% reduction in intrametastatic VEGF mRNA compared with sinusoidal tumors from vehicle-treated mice. Necrotic portal metastases increased 2-4-fold in treated mice. In vitro, Fas21 reduced VEGF secretion by HSCs and 51b cells dose-dependently. Additionally, HSCs migration in response to tumor soluble factors was dose-dependently diminished by Fas21, as was LSEC migration in response to HSCs and tumor soluble factors. Resveratrol analog Fas21 inhibits the proangiogenic response of HSCs and LSECs during the development of murine liver metastasis.