New eudesmane sesquiterpenoids from Atractylodis Macrocephalae Rhizoma and their inhibitory activities against SREBPs / 中国中药杂志

Three sesquiterpenoids were isolated and purified from the 95% ethanol extract of Atractylodis Macrocephalae Rhizoma by column chromatography on silica gel, Sephadex LH-20, ODS, and high-performance liquid chromatography(HPLC). Their chemical structures were identified on the basis of spectroscopic analysis and physiochemical properties as(7Z)-8β,13-diacetoxy-eudesma-4(15),7(11)-diene(1), 7-oxo-7,8-secoeudesma-4(15),11-dien-8-oic acid(2), and guai-10(14)-en-11-ol(3). Compounds 1 and 2 are new compounds and compound 3 was obtained from Compositae family for the first time. Compounds 1, 2, and 3 showed weak inhibitory activities against sterol regulatory element-binding proteins(SREBPs).

Study on the Effect and Mechanism of Ganoderic Acid C 2 on Lipid Metabolism of Hepatocytes by Regulating S6K/SREBPs Signaling Pathway / 中国药房

OBJECTIVE：To stu dy in vitro lipid-lowering effect of ganoderic acid C 2（GAC2），and to investigate its potential mechanism on the basis of S 6K/SREBPs signaling pathway. METHODS ：Using human liver cells HL- 7702 as objects ，MTT assay was used to test relative cell viability after treated with low ，medium and high doses （5，10，20 μmol/L，hereinafter）of GAC 2. Using lovastatin as positive control ，ELISA method was used to detect the contents of TC and TG in cells after treated with low ， medium and high doses of GAC 2. Nile red staining was used to observe the accumulation of lipids in cells. After transfected SREBPs report gene plasmid ，using 25-HC as positive control ，relative viability of SREBPs luciferase in cells were determined by luciferase assay after treated with low ，medium and high doses of GAC 2. Using 25-HC as positive control ，real-time fluorescent quantitative PCR was used to measure the mRNA expression of SREBPs and their downstream genes in cells after treated with medium and high doses of GAC 2. Using SREBPs inhibitor （25-HC）and S 6K inhibitor （rapamycin）as control ，Western blotting assay was adopted to determine the expression of SREBP- 1 and SREBP- 2（in the case of n-SREBPs ），relative expression ratio of phosphorylated S 6K to S 6K（p-S6K/S6K ratio ）. AutoDock 4.0 and other softwares were used for molecular docking of S 6K and GAC2. RESULTS ：There was no significant effect of low ， 0.05）. Compared with blank control group ，the content of TC qq.com in lovastatin group and GAC 2 high-dose group as well as thecontent of TG in lovastatin group ， GAC2 medium- and 床应用。电话：0371-65962746。E-mail：whui3697@126.com high-dose groups were decreased significantly （P＜0.05 or P＜ 0.01）；the number of lipid droplets in the cells of all medication groups decreased. Compared with blank control group ，relative viability of SREBPs luciferase in 25-HC group ，GAC2 low-，medium- and high-dose groups were decreased significantly ；mRNA expression of HMGCS1，MVK，SCD，HMGCR gene in 25-HC group and GAC 2 medium-，high-dose groups ，mRNA expression of DHCR7 gene in 25-HC group ，mRNA expression of SREBP-2 gene in GAC- 2 high-dose group as well as mRNA expression of DHCR24 and MSMO2 gene in 25-HC group and GAC 2 high-dose group were all decreased significantly ；relative protein expression of n-SREBP- 1 in 25-HC group ，GAC2 low-，medium- and high-dose groups ，relative protein expression of n-SREBP- 2 in 25-HC group and GAC 2 high-dose group as well as p-S 6K/S6K ratio in rapamycin group and GAC 2 groups were decreased significantly （P＜0.05 or P＜0.01）. The molecular docking results showed that GAC 2 could bound to amino acid residues Arg 335，Arg330 and Ala332 of S 6K via hydrogen bond. CONCLUSIONS ：GAC2 can reduce the lipid level of HL- 7702 cells，which may be associated with inhibiting the expression of S 6K/SREBPs signaling pathway.

Role of sterol regulatory element-binding proteins in lipid metabolism-related diseases / 基础医学与临床

Sterol regulatory element-binding proteins(SREBPs),as a major regulator of liposome in vivo,plays an important role in controlling liver lipid synthesis and inducing expression of genes involved in fatty acid,triglyceride and cholesterol synthesis.Part of the traditional Chinese medicine and its derivatives through the SREBP can be tar-get treatment of lipid metabolism related diseases.

The second-generation antipsychotic drugs induced dyslipidemia: a review of research and mechanisms / 中国药学杂志

Chronic administration of the second-generation antipsychotic drugs (SGAs) is associated with elevated risks of weight gain, obesity and other metabolic disorders, which further leads to an increase in incidence of cardiovascular diseases and the reduced life expectancy in patients. Dyslipidemia is a critical causative factor for the metabolic syndrome. In this article, the potential molecular mechanisms in SGA-induced dyslipidemia were focused on SREBPs/AMPKα/PPAR pathways, as well as the induction of insulin resistance in peripheral tissues (liver and white fat tissue).

Petroleum ether sub-fraction of rosemary extract improves hyperlipidemia and insulin resistance by inhibiting SREBPs / 中国天然药物

As a culinary and medicinal herb, rosemary is widely used. The present work aimed to investigate the effects of rosemary extracts on metabolic diseases and the underlying mechanisms of action. Liver cells stably expressing SREBP reporter were used to evaluate the inhibitory effects of different fractions of rosemary extracts on SREBP activity. The obese mice induced by Western-type diet were orally administered with rosemary extracts or vehicle for 7 weeks, the plasma and tissue lipids were analyzed. SREBPs and their target genes were measured by quantitative RT-PCR. We demonstrated that the petroleum ether sub-fraction of rosemary extracts (PER) exhibited the best activity in regulating lipid metabolism by inhibiting SREBPs, while water and n-BuOH sub-fraction showed the SREBPs agonist-effect. After PER treatment, there was a significant reduction of total SREBPs in liver cells. PER not only decreased SREBPs nuclear abundance, but also inhibited their activity, resulting in decreased expression of SREBP-1c and SREBP-2 target genes in vitro and in vivo. Inhibiting SREBPs by PER decreased the total triglycerides and cholesterol contents of the liver cells. In the mice fed with Western-type diet, PER treatment decreased TG, TC, ALT, glucose, and insulin in blood, and improved glucose tolerance and insulin sensitivity. Furthermore, PER treatment also decreased lipid contents in liver, brown adipose tissue, and white adipose tissue. Our results from the present study suggested that petroleum ether fraction of rosemary extracts exhibited the best potential of improving lipid metabolism by inhibiting SREBPs activity.

The Effects of Genistein to Expression of Fatty Acid Synthase in Breast Cancer Cells / 한국유방암학회지

PURPOSE: The relatively low incidence of breast cancer in Asian countries with cultures which traditionally eat a large amount of soy is worth noticing in research fields. Genistein is a isoflavone phytoestrogen found in soy and its consumption may have a role in cancer etiology. We have established a hypothesis that a diet high in soy consumption is related to a low incidence of breast cancer. Fatty acid synthase (FAS) is a multi-protein enzyme responsible for de novo biosynthesis of fatty acids. Recent studies have demonstrated that high levels of FAS occurs in a subset of human cancers, such as breast cancer, ovarian cancer, and prostate cancer. High level of FAS are associated with a poor prognosis. Sterol regulatory element binding proteins (SREBPs) are a family of transcription factors that regulate genes involved in lipid metabolism, including FAS. Recent studies show that expression of SREBP1c is correlates with FAS expression. The aim of this study is to investigate the effect of genistein on the expression of FAS in breast cancer cells. METHODS: We performed immunofluorescent staining to examine the expression of FAS under different concentration of genistein. RT-PCR was also performed to investigate the mRNA expression of FAS and SREBP1c in different conditioned breast cancer cells treated with different concentration of FAS inhibitor and genistein. RESULTS: By immunofluorescent staining, the FAS expression after treatment with the FAS inhibitor, C75, decreased at a micron10 M concentration. However the expression of FAS decreased at all concentrations of genistein (0.5, 1, 5, 10 micronM). The mRNA levels of FAS and SREBP1c after treatment with C75 decreased constantly according to time and concentration. However the effect was noted only after 12 hr. The mRNA level of FAS and SREBP1c following treatment with genistein decreased at only a 10 micronM concentration (p<0.005). CONCLUSION: Genistein may down regulate FAS expression in breast cancer cells through modulation of SREBP-1c. This finding may account for the relatively low incidence of breast cancer in Asians who consume a large amount of soy in their diet.

Regulación del metabolismo del colesterol y ácidos grasos en el síndrome nefrótico experimental por las proteínas que se unen a los elementos regulatorios de esteroles (SREBP's): efecto de la soya / Metabolism of cholesterol and fatty acids in nephrotic syndrome and its regulation by sterol regulatory element brinding proteins (SREBP's): Effect of soy protein consumption

El síndrome nefrótico (SN) cursa con hiperlipidemia. Se conoce que la biosíntesis del colesterol y de los ácidos grasos es regulada por los factores transcripcionales que se unen a los elementos de respuesta a esteroles (SREBP's). El consumo de proteína de soya disminuye la concentración de estos lípidos, aunque su mecanismo de acción no es del todo conocido. El objetivo de este estudio fue conocer si el consumo de la proteína de soya reduce los niveles de colesterol y triglicéridos a través de una regulación de las SREBP 's. Se estudiaron ratas Wistar macho con SN experimental por 64 días. Se observó que las concentraciones plasmáticos de colesterol y triglicéridos plasmáticos, así como de la proteinuria eran significativamente menores en las ratas alimentadas con proteína de soya que aquellas que consumían caseína. Estos cambios se asociaron con disminución de la expresión del ARNm SREBP 1 y de las enzimas de la síntesis de ácidos grasos. Los análisis por Western Blot revelaron que en los núcleos de hepatocitos obtenidos de ratas alimentadas con proteína de soya hubo menor presencia del factor transcripcional SREBP 1. Los resultados de este estudio indican que el consumo de proteína de soya produce efectos benéficos durante el síndrome nefrótico.

Hyperlipidemia occurs during nephrotic syndrome (NS). It is known that cholesterol and fatty acid biosynthesis is controlled by the transcription factors sterol regulatory element binding proteins (SREBPs). Soy protein consumption reduces the concentration of these lipids, although its mechanism of action is not well known. The aim of the present study was to establish whether soy protein consumption reduces cholesterol and triglycerides levels by regulating of SREBPs. Male Wistar rats with experimental NS were studied for 64 days. The results showed that rats fed with soy protein had significantly lower plasma cholesterol and triglyceride concentrations as well as proteinuria than rats fed with casein diet. These decrements were associated with a decrease in the expression of SREBP 1 and fatty acid biosynthetic enzymes. In addition, Western blot analysis revealed that in nuclear extracts from hepatocytes of rats fed with soy protein, there was a lower concentration of SREBP 1 than in rats fed with casein. The results of this study indicate that consumption of a soy protein diet has beneficial effects on nephrotic syndrome.