期刊：
Cardiovascular & Hematological Disorders - Drug Targets,2012年12(2):- ISSN：1871-529X
作者机构：
Key Laboratory for Atherosclerology of Hunan Province, Institute of Cardiovascular Research, University of South China, Hengyang, Hunan, China<&wdkj&>
摘要：
The role of renal lipoprotein lipase (LPL) per se in kidney diseases is still controversial and obscure. The purpose of this study was to observe the preventive effects of Ibrolipim, a LPL activator, on lipid accumulation and LPL expression in the kidneys of minipigs fed a high-sucrose and high-fat diet (HSFD). Male Chinese Bama minipigs were fed a control diet or HSFD with or without 0.1 g/kg/day Ibrolipim for 5 months. Body weight, plasma glucose, insulin, lipids, LPL activity, and urinary microalbumin were measured. Renal tissue was obtained for detecting LPL activity and contents of triglyceride and cholesterol, observing the renal lipid accumulation by Oil Red O staining, and examining the mRNA and protein expression of LPL by real time PCR, Western Blot and immunohistochemistry. Feeding HSFD to minipigs caused weight gain, hyperglycemia, hyperinsulinemia, hyperlipidemia and microalbuminuria. HSFD increased plasma LPL activity while it decreased the mRNA and protein expression and activity of LPL in the kidney. The increases in renal triglyceride and cholesterol contents were associated with the decrease in renal LPL activity of HSFD-fed minipigs. In contrast, supplementing Ibrolipim into HSFD lowered body weight, plasma glucose, insulin, triglyceride and urinary albumin concentrations while it increased plasma total cholesterol and HDL-C. Ibrolipim suppressed the renal accumulation of triglyceride and cholesterol, and stimulated the diet-induced down-regulation of LPL expression and activity in the kidney. Ibrolipim exerts renoprotective and hypolipidemic effects via the increase in renal LPL activity and expression, and thus the increased expression and activity of renal LPL play a vital role in suppressing renal lipid accumulation and ameliorating proteinuria in diet-induced diabetic minipigs.
作者机构：
[Xiao, Guohua; Wang, Zongbao; Yu, Jian; Zhang, Yali; Zhang, Sujun; Yin, Weidong; Wang, Yueting] Univ S China, Inst Biochem & Mol Biol, Hengyang 421001, Peoples R China.;[Wang, Zongbao] Univ S China, Dept Lab Anim Sci, Hengyang 421001, Peoples R China.;[Zeng, Huaicai] Univ S China, Sch Publ Hlth, Hengyang 421001, Peoples R China.
通讯机构：
[Wang, Zongbao] U;Univ S China, Inst Biochem & Mol Biol, Hengyang 421001, Peoples R China.
摘要：
Objective: Endothelial dysfunction is a key event in the onset and progression of atherosclerosis associated with diabetes. Increasing cell apoptosis may lead to endothelial dysfunction and contribute to vascular complications. Therefore, we aimed to elucidate the possible role and mechanism of ibrolipim in preventing endothelial dysfunction induced by high glucose. Methods: Human umbilical vein endothelial cells (HUVECs) were cultured respectively under normal glucose level (5.5 mM), high glucose level (33 mM), and high glucose level with ibrolipim treatment. Endothelial dysfunction was identified by the expression of ET-1 and vWF through reverse transcription PCR (RT-PCR). HUVECs apoptosis was assessed by fluorescent staining with Hoechst 33258. Akt activity was analyzed by western blot. Results: High glucose condition significantly increased the rate of apoptotic cells, weakened cell viability, and decreased the expression of ET-1 and vWF. Ibrolipim treatment significantly attenuated these alterations of endothelial dysfunction. The lower concentrations (2, 4, 8 μM) of ibrolipim inhibited apoptosis of cultured HUVECs, improved cell viability, down-regulated the mRNA levels of ET-1, vWF, and attenuated the cytotoxicity; however, higher concentration (16, 32 μM) of ibrolipim aggravated the damage of HUVECs cultured under high glucose level. Meanwhile, high glucose induced a decrease of Akt activity which led to apoptosis, and ibrolipim prevented the decrease and attenuated apoptotic effect induced by high glucose. Furthermore, the PI3K inhibitor LY294002 significantly abolished the anti-apoptotic effect of ibrolipim, and decreased Akt phosphorylation. Although, the expression of Akt mRNA and total protein were not altered in cultured HUVECs. Conclusion: Ibrolipim at lower concentrations can inhibit high glucose-induced apoptosis in cultured HUVECs, which might be related to the alternation of Akt activity. Ibrolipim has the potential to attenuate endothelial dysfunction and lower the risk of diabetes-associated vascular diseases. And it might be a therapeutic agent for diabetic vascular complications.
通讯机构：
[Yin, Weidong] U;Univ S China, Life Sci Res Ctr, Inst Cardiovasc Res, Key Lab Atherosclerol Hunan Prov, Hengyang 421001, Hunan, Peoples R China.
摘要：
Insulin resistance and dyslipidemia are both considered to be risk factors for metabolic syndrome. Low levels of IGF1 are associated with insulin resistance. Elevation of low-density lipoprotein cholesterol (LDL-C) concomitant with depression of high-density lipoprotein cholesterol (HDL-C) increase the risk of obesity and type 2 diabetes mellitus (T2DM). Liver secretes IGF1 and catabolizes cholesterol regulated by the rate-limiting enzyme of bile acid synthesis from cholesterol 7 alpha-hydroxylase (CYP7A1). NO-1886, a chemically synthesized lipoprotein lipase activator, suppresses diet-induced insulin resistance with the improvement of HDL-C. The goal of the present study is to evaluate whether NO-1886 upregulates IGF1 and CYP7A1 to benefit glucose and cholesterol metabolism. By using human hepatoma cell lines (HepG2 cells) as an in vitro model, we found that NO-1886 promoted IGF1 secretion and CYP7A1 expression through the activation of signal transducer and activator of transcription 5 (STAT5). Pretreatment of cells with AG 490, the inhibitor of STAT pathway, completely abolished NO1886-induced IGF1 secretion and CYP7A1 expression. Studies performed in Chinese Bama minipigs pointed out an augmentation of plasma IGF1 elicited by a single dose administration of NO-1886. Long-term supplementation with NO-1886 recovered hyperinsulinemia and low plasma levels of IGF1 suppressed LDL-C and facilitated reverse cholesterol transport by decreasing hepatic cholesterol accumulation through increasing CYP7A1 expression in high-fat/high-sucrose/high-cholesterol diet minipigs. These findings indicate that NO-1886 upregulates IGF1 secretion and CYP7A1 expression to improve insulin resistance and hepatic cholesterol accumulation, which may represent an alternative therapeutic avenue of NO-1886 for T2DM and metabolic syndrome. Journal of Endocrinology (2010) 204, 47-56
期刊：
Clinical and Experimental Pharmacology and Physiology,2009年36(9):e32-e39 ISSN：0305-1870
通讯作者：
Liao, Duan-Fang
作者机构：
[Ling, Hong-Yan; Liao, Duan-Fang] Cent S Univ, Dept Pharmacol, Sch Pharmaceut Sci, Changsha, Hunan, Peoples R China.;[Tang, Cao-Ke; Zhang, Liang; Yin, Wei-Dong; Liao, Duan-Fang] Univ S China, Res Ctr Life Sci, Key Lab Atherosclerol Hunan Prov, Hengyang 421001, Hunan, Peoples R China.;[Chen, Lin-Xi; Gao, Zhi-Ping; Zhang, Xiao-Ying; Zhu, Bing-Yang; Ou, He-Sheng; Ling, Hong-Yan; Tuo, Qin-Hui; Liao, Duan-Fang] Univ S China, Res Ctr Life Sci, Key Lab Pharmacoprote Hunan Prov, Inst Pharm & Pharmacol, Hengyang 421001, Hunan, Peoples R China.;[Ling, Hong-Yan] Univ S China, Res Ctr Life Sci, Dept Physiol, Sch Med, Hengyang 421001, Hunan, Peoples R China.;[Feng, Shui-Dong] Univ S China, Res Ctr Life Sci, Sch Publ Hlth, Dept Epidemiol, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Liao, Duan-Fang] U;Univ S China, Res Ctr Life Sci, Key Lab Atherosclerol Hunan Prov, 28 W Chengsheng Rd, Hengyang 421001, Hunan, Peoples R China.
摘要：
Evidences indicate that a complex relationship exists among sleep disorders, obesity and insulin resistance. NEU-P11 is a novel melatonin agonist used in treatment of psychophysiological insomnia, and in animal studies NEU-P11 showed sleep-promoting effect. In this study, we applied NEU-P11 on obese rats to assess its potential melatoninergic effects in vivo. Obese models were established using high-fat/high-sucrose-fed for 5 months. NEU-P11 (10 mg/kg)/melatonin (4 mg/kg)/vehicle were administered by a daily intraperitoneal injection respectively for 8 weeks. Our results showed that NEU-P11 or melatonin inhibited both body weight gain and deposit of abdominal fat with no influence on food intake. The impaired insulin sensitivity and antioxidative potency were improved and the levels of plasma glucose, total cholesterol (TC), triglycerides (TG) decreased with an increased in HDL-cholesterol (HDL-c) after NEU-P11 or melatonin administration. These data suggest that NEU-P11, like melatonin, decreased body weight gain and improved insulin sensitivity and metabolic profiles in obese rats. We conclude that NEU-P11 has a melatoninergic effect on regulating body weight in obese rats and also improving metabolic profiles and efficiently enhancing insulin sensitivity. (C) 2009 Elsevier Ltd. All rights reserved.
