• Title/Summary/Keyword: sterol regulatory element binding protein 1

Search Result 149, Processing Time 0.04 seconds

Inhibition of Adipocyte Differentiation through G1 Arrest by Extract of Sophora tonkinensis Gapnep in 3T3-L1 Preadipocytes (산두근 추출물의 세포주기 정지를 통한 3T3-L1 지방전구세포의 분화 억제)

  • Jeong, Hyun-Young;Hyun, Sook-Kyung;Choi, Yung-Hyun;Kim, Byung-Woo;Kwon, Hyun-Ju
    • Journal of Life Science
    • /
    • v.21 no.9
    • /
    • pp.1346-1353
    • /
    • 2011
  • Sophora tonkinensis Gapnep has been used as a traditional herbal medicine in oriental regions since ancient times. In this study, the effect and mechanism of the MeOH extract of Sophora tonkinensis Gapnep (STME) on adipocite differentiation and adipogenesis in 3T3-L1 preadipocites were investigated. Treatment with STME in the concentration range of 0-200 ${\mu}g$/ml significantly inhibited the differentiation of 3T3-L1 preadipocites in a dose-dependent manner, as determined by a decrease in intracellular lipid droplets and lipid contents measured by Oil Red O staining. In association with the inhibitory effect of lipid accumulation, the expressions of the proteins concerned with adipogenesis in 3T3-L1 preadipocites were also investigated. Treatment with STME reduced the expressions of peroxisome proliferator-activated receptor ${\gamma}$ (PPAR${\gamma}$), cytidine-cytidine-adenosine-adenosine-thymine (CCAAT)/enhancer-binding proteins ${\alpha}$ and ${\beta}$ (C/EBP${\alpha}$ and C/EBP${\beta}$) and sterol regulatory element binding protein (SREBP), which are adipocyte specific markers. In flow cytometry analysis, the inhibitory effect of differentiation was caused by G1 arrest and following mitotic clonal expansion cease. Therefore, we also investigated the alteration of G1 phase arrest-related proteins. As a result, the expression of p21 protein was significantly increased, while the expressions of Cdk2, E2F-1 and phospho-Rb were reduced in a dose-dependent manner in STME treated 3T3-L1 cells. According to these results, STME might inhibit differentiation through G1 arrest in 3T3-L1 preadipocytes adipogenesis, and further studies, which are in progress, have to be completed to identify the active compounds.

Inhibition of Lipase Activity and Preadipocyte Differentiation in 3T3-L1 Cells Treated with Sargassum horneri Extract (괭생이모자반 추출물의 리파아제 저해 활성 및 3T3-L1 지방전구세포 분화억제 효과)

  • Hong, Ji Woo;Park, Ha Young;Park, Jae Hyun;Kim, So Hee;Kim, Han A;Kim, Jin-Woo
    • Ocean and Polar Research
    • /
    • v.44 no.1
    • /
    • pp.61-67
    • /
    • 2022
  • In this study, in order to evaluate the anti-obesity effect of sargassum horneri extract, the effects of the extract on lipase activity and preadipocyte differentiation in 3T3-L1 cells were investigated. S. horneri extract between 0.0 and 1.0 mg/mL showed no cytotoxicity and inhibited lipase activity by 68.1%. When S. horneri extract was utilized at levels of 0.25, 0.5, and 1.0 mg/mL in 3T3-L1 cells, preadipocytes differentiation decreased by 11.4, 19.7, and 25.6%, respectively, showing anti-obesity effects. In addition, after treatment with 1.0 mg/mL S. horneri extract, the mRNA expression levels of sterol regulatory element binding proteins-1c (SREBP-1c), peroxisome proliferator activated receptor-γ (PPAR-γ), CCAAT enhancer binding protein-α (CEBP-α), fatty acid synthase (FAS), and stearoyl-CoA desaturase1 (SCD1) in 3T3-L1 cells were significantly decreased (p < 0.05) by 65.2, 54.9, 50.0, 33.8, and 33.8% respectively. These results showed that S. horneri extract suppresses lipase activity and prophylactic preadipocyte differentiation in 3T3-L1, and thus can be used as an anti-obesity agent in functional foods and medicines.

Downregulation of Hepatic De Novo Lipogenesis and Adipogenesis in Adipocytes by Pinus densiflora Bark Extract

  • Ahn, Hyemyoung;Jeong, Jeongho;Moyo, Knowledge Mudhibadi;Ryu, Yungsun;Min, Bokkee;Yun, Seong Ho;Kim, Hwa Yeon;Kim, Wooki;Go, Gwang-woong
    • Journal of Microbiology and Biotechnology
    • /
    • v.27 no.11
    • /
    • pp.1925-1931
    • /
    • 2017
  • Korean red pine (Pinus densiflora) bark extract, PineXol (PX), was investigated for its potential antioxidant and anti-inflammation effects in vitro. It was hypothesized that PX treatment ($25-150{\mu}g/ml$) would reduce the lipid synthesis in HepG2 hepatocytes as well as lipid accumulation in 3T3-L1 adipocytes. Hepatocytes' intracellular triglycerides and cholesterol were decreased in the PX $150{\mu}g/ml$ treatment group compared with the control (p < 0.05). Consequently, de novo lipogenic proteins (acetyl-CoA carboxylase 1, stearoyl-CoA desaturase 1, elongase of very long chain fatty acids 6, glycerol-3-phosphate acyltransferase 1, and sterol regulatory element-binding protein 1) were significantly decreased in hepatocytes by PX $150{\mu}g/ml$ treatment compared with the control (p < 0.05). In differentiated 3T3-L1 adipocytes, the lipid accumulation was significantly attenuated by all PX treatments (p < 0.01). Regulators of adipogenesis, including CCAAT-enhancer-binding proteins alpha, peroxisome proliferatoractivated receptor gamma, and perilipin, were decreased in PX $100{\mu}g/ml$ treatment compared with the control (p < 0.05). In conclusion, PX might have anti-obesity effects by blocking hepatic lipogenesis and by inhibiting adipogenesis in adipocytes.

SAFB1, an RBMX-binding protein, is a newly identified regulator of hepatic SREBP-1c gene

  • Omura, Yasushi;Nishio, Yoshihiko;Takemoto, Tadashi;Ikeuchi, Chikako;Sekine, Osamu;Morino, Katsutaro;Maeno, Yasuhiro;Obata, Toshiyuki;Ugi, Satoshi;Maegawa, Hiroshi;Kimura, Hiroshi;Kashiwagi, Atsunori
    • BMB Reports
    • /
    • v.42 no.4
    • /
    • pp.232-237
    • /
    • 2009
  • Sterol regulatory element-binding protein (SREBP)-1c plays a crucial role in the regulation of lipogenic enzymes in the liver. We previously reported that an X-chromosome-linked RNA binding motif (RBMX) regulates the promoter activity of Srebp-1c. However, still unknown was how it regulates the gene expression. To elucidate this mechanism, we screened the cDNA library from mouse liver by yeast two-hybrid assay using RBMX as bait and identified scaffold attachment factor B1 (SAFB1). Immunoprecipitation assay demonstrated binding of SAFB1 to RBMX. Chromatin immunoprecipitation assay showed binding of both SAFB1 and RBMX to the upstream region of Srebp-1c gene. RNA interference of Safb1 reduced the basal and RBMX-induced Srebp-1c promoter activities, resulting in reduced Srebp-1c gene expression. The effect of SAFB1 overexpression on Srebp-1c promoter was found only in the presence of RBMX. These results indicate a major role for SAFB1 in the activation of Srebp-1c through its interaction with RBMX.

Regulation of PPAR and SREBP-1C Through Exercise in White Adipose Tissue of Female C57BL/6J Mice

  • Jeong, Sun-Hyo
    • Biomedical Science Letters
    • /
    • v.18 no.3
    • /
    • pp.227-236
    • /
    • 2012
  • Previous study showed that swimming improved obesity but was not through $PPAR{\alpha}$ activation in liver and skeletal muscle in high fat diet-fed female mice with functioning ovaries as an animal model of obese premenopausal women. Thus, this study was aimed at investigation of the effects of swimming on the promotion of health and its molecular mechanism in adipose tissue of high fat diet-fed female mice. Eight-week-old female C57BL/6J mice were randomly divided into two groups (a non-swim control group and a swim group, n=8/group). Mice in the swim group swam for 2 h daily for 6 weeks in water bath with temperature of $35{\pm}1^{\circ}C$. All the animals received high fat diet (45% kcal fat) for 6 weeks. Reverse transcription-polymerase chain reaction was used to elucidate the molecular mechanism. Female mice subjected to swimming had significantly decreased body weight gain and white adipose tissue mass compared with the female control mice. Histological studies illustrated that swimming decreases the hepatic lipid accumulation. As expected, swimming did not affect the expression of mRNA levels of peroxisome proliferator-activated receptor (PPAR) ${\alpha}$ and $PPAR{\alpha}$ target genes responsible for mitochondrial fatty acid ${\beta}$-oxidation, such as carnitine palmitoyltransgerase-1 and medium chain acyl-CoA dehydrogenase in the white adipose tissue. However, mice that underwent 6-weeks of swimming exercise had decreased the mRNA expression of lipogenic genes, such as sterol regulatory element-binding proteins-1C and fatty acid synthase in comparison to sedentary control mice, with decreased $PPAR{\gamma}$ target genes involved in adipocyte-specific marker genes, such as adipocyte fatty acid binding protein and leptin in the white adipose tissue. These results suggest that swimming can effectively prevent obesity induced by high fat diet-fed, in part through down-regulation of adipogenesis and lipogenesis in white adipose tissue of female obese mice. Moreover, these results suggest that swimming maybe contributing the promotion of health through regulation of adipogenesis and lipogenesis in overweight premenopausal women.

Conjugated Linoleic Acid as a Key Regulator of Performance, Lipid Metabolism, Development, Stress and Immune Functions, and Gene Expression in Chickens

  • Choi, Yang-Ho
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.22 no.3
    • /
    • pp.448-458
    • /
    • 2009
  • It has been well documented from animal and human studies that conjugated linoleic acid (CLA) has numerous beneficial effects on health. In chickens, CLA exerts many effects on performance ranging from egg quality and yolk lipids to meat quality. Although there are several CLA isomers available, not all CLA isomers have the same incorporation rates into egg yolk: cis-9,trans-11 and trans-10,cis-12 CLA isomers are more favorably deposited into egg yolk than other isomers investigated, but of the two isomers, the former has a higher incorporation rate than the latter. CLA alters the amounts and profiles of lipids in plasma, muscles and liver. Furthermore, increased liver weight was reported in chickens fed dietary CLA. As observed in egg yolk, marked reduction in intramuscular lipids as well as increased protein content was observed in different studies, leading to elevation in protein-to-fat ratio. Inconsistency exists for parameters such as body weight gain, feed intake, feed conversion ratio, egg production rate and mortality, depending upon experimental conditions. One setback is that hard-cooked yolks from CLA-consuming hens have higher firmness as refrigeration time and CLA are increased, perhaps owing to alterations in physico-chemistry of yolk. Another is that CLA can be detrimental to hatchability when provided to breeders: eggs from these breeders have impaired development in embryonic and neonatal stages, and have increased and decreased amounts of saturated fatty acids and monounsaturated fatty acids (MUFAs), respectively. Thus, both problems can be fully resolved if dietary sources rich in MUFAs are provided together with CLA. Emerging evidence suggests that CLA exerts a critical impact on stress and immune functions as it can completely nullify some of the adverse effects produced by immune challenges and reduce mortality in a dose-dependent manner. Finally, CLA is a key regulator of genes that may be responsible for lipid metabolism in chickens. CLA down-regulates both expression of the gene encoding stearoyl-CoA desaturase-1 and its protein activity in the chicken liver while up-regulating mRNA of sterol regulatory element-binding protein-l.

Gene Microarray Analysis for Porcine Adipose Tissue: Comparison of Gene Expression between Chinese Xiang Pig and Large White

  • Guo, W.;Wang, S.H.;Cao, H.J.;Xu, K.;Zhang, J.;Du, Z.L.;Lu, W.;Feng, J.D.;Li, N.;Wu, C.H.;Zhang, L.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.21 no.1
    • /
    • pp.11-18
    • /
    • 2008
  • We created a cDNA microarray representing approximately 3,500 pig genes for functional genomic studies. The array elements were selected from 6,494 cDNA clones identified in a large-scale expressed sequence tag (EST) project. These cDNA clones came from normalized and subtracted porcine adipose tissue cDNA libraries. Sequence similarity searches of the 3,426 ESTs represented on the array using BLASTN identified 2,790 (81.4%) as putative human orthologs, with the remainder consisting of "novel" genes or highly divergent orthologs. We used the gene microarray to profile transcripts expressed by adipose tissue of fatty Chinese Xiang pig (XP) and muscley Large White (LW). Microarray analysis of RNA extracted from adipose tissue of fatty XP and muscley LW identified 81 genes that were differently expressed two fold or more. Transcriptional differences of four of these genes, adipocyte fatty acid binding protein (aP2), stearyl-CoA desaturase (SCD), sterol regulatory element binding transcription factor 1 (SREBF1) and lipoprotein lipase (LPL) were confirmed using SYBR Green quantitative RT-PCR technology. Our results showed that high expression of SCD and SREBF1 may be one of the reasons that larger fat deposits are observed in the XP. In addition, our findings also illustrate the potential power of microarrays for understanding the molecular mechanisms of porcine development, disease resistance, nutrition, fertility and production traits.

The Effects of Hoechunyanggyeok-san on hyperglycemia and Dyslipidemia in db/db mice (회춘양격산(回春凉膈散)이 db/db 마우스의 고혈당 및 지질대사에 미치는 효과)

  • Jang, Soo-Young;Jung, Yu-Sun;Shin, Hyeon-Cheol
    • The Journal of Internal Korean Medicine
    • /
    • v.35 no.1
    • /
    • pp.70-78
    • /
    • 2014
  • Objectives : Hoechunyanggyeok-san (HYS) is a traditional herbal medicine, which has been clinically used for treating febrile and inflammatory diseases. HYS has been reported to be a useful treatment for diabetes, atherosclerosis and hyperlipidemia in the type 1 diabetic model. However, the mechanism of the effects of HYS against hyperglycemia and hyperlipidemia is poorly understood. In the present study, we investigated the underlying mechanism of ameliorative effect of HYS on hyperglycemia and hyperlipidemia in vivo. Methods : HYS (10, 50 mg/kg/day, p.o.) was administered every day for 2 weeks to db/db mice and its effect was compared with vehicle-treated db/db mice. To confirm serum glucose and triglyceride (TG) changes, serological testing was performed. The levels of sterol regulatory element-binding protein-1 (SREBP-1) activity and Sirtuin1 (SIRT1), AMP-activated protein kinase (AMPK), and acetyl-CoA carboxylase ${\alpha}$ ($ACC{\alpha}$) expression were analyzed by western blot analysis. Results : The administration of HYS significantly decreased the elevated serum glucose and TG in db/db mice. HYS administration increased the levels of SIRT1 and AMPK expression compared with the vehicle-treated group. Moreover, HYS treatment significantly inhibited SREBP-1 activity and $ACC{\alpha}$ expression in the liver, while the vehicle-treated group exhibited their increase. Conclusions : In conclusion, HYS is suggested to have an improvement effect on hyperglycemia and hyperlipidemia by activating the SIRT1/AMPK signaling pathway and inhibiting SREBP-1.

Protective Effect of Isoliquiritigenin against Ethanol-Induced Hepatic Steatosis by Regulating the SIRT1-AMPK Pathway

  • Na, Ann-Yae;Yang, Eun-Ju;Jeon, Ju Mi;Ki, Sung Hwan;Song, Kyung-Sik;Lee, Sangkyu
    • Toxicological Research
    • /
    • v.34 no.1
    • /
    • pp.23-29
    • /
    • 2018
  • Ethanol-induced fat accumulation, the earliest and most common response of the liver to ethanol exposure, may be involved in the pathogenesis of liver diseases. Isoliquiritigenin (ISL), an important constituent of Glycyrrhizae Radix, is a chalcone derivative that exhibits antioxidant, anti-inflammatory, and phytoestrogenic activities. However, the effect of ISL treatment on lipid accumulation in hepatocytes and alcoholic hepatitis remains unclear. Therefore, we evaluated the effect and underlying mechanism of ISL on ethanol-induced hepatic steatosis by treating AML-12 cells with 200 mM ethanol and/or ISL ($0{\sim}50{\mu}M$) for 72 hr. Lipid accumulation was assayed by oil red O staining, and the expression of sirtuin1 (SIRT1), sterol regulatory element-binding protein-1c (SREBP-1c), AMP-activated protein kinase (AMPK), and peroxisome proliferator-activated receptor alpha ($PPAR{\alpha}$) was studied by western blotting. Our results indicated that ISL treatment upregulated SIRT1 expression and downregulated SREBP-1c expression in ethanol-treated cells. Similarly, oil red O staining revealed a decrease in ethanol-induced fat accumulation upon co-treatment of ethanol-treated cells with 10, 20, and $50{\mu}M$ of ISL. These findings suggest that ISL can reduce ethanol induced-hepatic lipogenesis by activating the SIRT1-AMPK pathway and thus improve lipid metabolism in alcoholic fatty livers.

Effects of Kisspeptin-10 on Lipid Metabolism in Cultured Chicken Hepatocytes

  • Wu, J.;Fu, W.;Huang, Y.;Ni, Y.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.25 no.9
    • /
    • pp.1229-1236
    • /
    • 2012
  • Our previous studies showed that kisspeptin-10 (Kp-10) injected in vivo can markedly increase lipid anabolism in liver of quails. In order to investigate the direct effect of Kp-10 on lipid metabolism of hepatocytes in birds, cells were separated from embryos livers and cultured in vitro with 0, 100 and 1,000 nM Kp-10, respectively. The results showed that after 24 h treatment, cells viability was not affected by 100 nM Kp-10, but showed a mild decrease with 1,000 nM Kp-10 compared to the control cells. Based on the results of the cell viability, 100 nM dosage of Kp-10 was selected for the further study and analysis. Compared with control cells, total cholesterol (Tch) contents in 100 nM treated cells were increased by 51.23%, but did not reach statistical significance, while the level of triglyceride (TG), high density of lipoprotein-cholesterol (HDL-C) and low density of lipoprotein-cholesterol (LDL-C) were significantly increased. Real-time PCR results showed that ApoVLDL-II mRNA expression had a tendency to increase, genes including sterol regulatory element-binding protein-1 (SREBP-1), acetyl coenzyme A carboxylase ${\alpha}$ ($ACC{\alpha}$), carnitine palmitoyltransferase 1 (CPT1), 3-hydroxyl-3-methylglutaryl-coenzyme A reductases (HMGCR) and stearyl coenzyme A dehydrogenase-1 (SCD1) mRNA in hepatocytes were significantly down-regulated by 100 nM Kp-10. However, contrary to its gene expression, SREBP-1 protein expression was significantly up-regulated by 100 nM Kp-10. Some of the significant correlations in mRNA expression were found between genes encoding hepatic factors or enzymes involved in lipid metabolism in liver of birds. These results indicate that Kp-10 stimulates lipid synthesis directly in primary cultured hepatocytes of chickens.