ABSTRACT
Farnesoid X receptor (FXR) is a member of the nuclear receptor superfamily of ligand-activated transcription factors. As a metabolic regulator, FXR plays key roles in bile acid and cholesterol metabolism and lipid and glucose homeostasis. Therefore, FXR is a potential drug target for several metabolic syndromes, especially those related to lipidemia disorders. In the present study, we identified small molecule SIPI-7623, a derivative of an extract from Oriental wormwood (Artemisia capillaris), and found that it specifically upregulated the expression of cholesterol-7-alpha-hydroxylase (CYP7A1), downregulated the expression of sterol-regulatory element-binding protein 1c (SREBP-1c) in the liver, and inhibited the expression of ileal bile acid binding-protein (IBABP) in the ileum of rats. We found that inhibition of FXR by SIPI-7623 decreased the level of cholesterol and triglyceride. SIPI-7623 reduced the levels of cholesterol and triglyceride in in vitro HepG2 cell models, ameliorated diet-induced atherosclerosis, and decreased the serum lipid content on rats and rabbits model of atherosclerosis in vivo. Furthermore, SIPI-7623 decreased the extent of atherosclerotic lesions. Our resutls demonstrated that antagonism of the FXR pathway can be employed as a therapeutic strategy to treat metabolic diseases such as hyperlipidemia and atherosclerosis. In conclusion, SIPI-7623 could be a promising lead compound for development of drugs to treat hyperlipidemia and atherosclerosis.
Subject(s)
Animals , Humans , Male , Rabbits , Rats , Artemisia , Chemistry , Atherosclerosis , Drug Therapy , Genetics , Metabolism , Cholesterol , Metabolism , Cholesterol 7-alpha-Hydroxylase , Genetics , Metabolism , Drugs, Chinese Herbal , Hyperlipidemias , Drug Therapy , Genetics , Metabolism , Hypolipidemic Agents , Liver , Metabolism , Rats, Sprague-Dawley , Receptors, Cytoplasmic and Nuclear , Genetics , Metabolism , Sterol Regulatory Element Binding Protein 1 , Genetics , Metabolism , Triglycerides , MetabolismABSTRACT
Farnesoid X receptor (FXR) is a member of the nuclear receptor superfamily of ligand-activated transcription factors. As a metabolic regulator, FXR plays key roles in bile acid and cholesterol metabolism and lipid and glucose homeostasis. Therefore, FXR is a potential drug target for several metabolic syndromes, especially those related to lipidemia disorders. In the present study, we identified small molecule SIPI-7623, a derivative of an extract from Oriental wormwood (Artemisia capillaris), and found that it specifically upregulated the expression of cholesterol-7-alpha-hydroxylase (CYP7A1), downregulated the expression of sterol-regulatory element-binding protein 1c (SREBP-1c) in the liver, and inhibited the expression of ileal bile acid binding-protein (IBABP) in the ileum of rats. We found that inhibition of FXR by SIPI-7623 decreased the level of cholesterol and triglyceride. SIPI-7623 reduced the levels of cholesterol and triglyceride in in vitro HepG2 cell models, ameliorated diet-induced atherosclerosis, and decreased the serum lipid content on rats and rabbits model of atherosclerosis in vivo. Furthermore, SIPI-7623 decreased the extent of atherosclerotic lesions. Our resutls demonstrated that antagonism of the FXR pathway can be employed as a therapeutic strategy to treat metabolic diseases such as hyperlipidemia and atherosclerosis. In conclusion, SIPI-7623 could be a promising lead compound for development of drugs to treat hyperlipidemia and atherosclerosis.
Subject(s)
Animals , Humans , Male , Rabbits , Rats , Artemisia , Chemistry , Atherosclerosis , Drug Therapy , Genetics , Metabolism , Cholesterol , Metabolism , Cholesterol 7-alpha-Hydroxylase , Genetics , Metabolism , Drugs, Chinese Herbal , Hyperlipidemias , Drug Therapy , Genetics , Metabolism , Hypolipidemic Agents , Liver , Metabolism , Rats, Sprague-Dawley , Receptors, Cytoplasmic and Nuclear , Genetics , Metabolism , Sterol Regulatory Element Binding Protein 1 , Genetics , Metabolism , Triglycerides , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To study and compare the anti-inflammatory effect and molecular mechanism of artemisinin and dihydroartemisinin.</p><p><b>METHOD</b>Mouse mononuclear macrophage RAW264.7 cells were stimulated to release inflammatory mediators such as TNF-alpha, IL-6 and NO, in order to assess the drugs' inhibitory effect on macrophage's release of above inflammatory mediators. The levels of TNF-alpha and IL-6 were determined by ELISA and the cytotoxicity was determined by MTT method. The protein expression of iNOS, COX-2 and beta-actin were tested by Western blot. The enzymatic activity of COX-2 was determined by colorimetric method.</p><p><b>RESULT</b>Dihydroartemisinin significantly inhibited LPS-induced release of TNF-alpha, IL-6 and NO from RAW264.7 in mice with the concentration range of 12.5 - 100 micromol x L(-1), and showed good dose dependence. Artemisinin only inhibited the IL-6 release to a certain extent.</p><p><b>CONCLUSION</b>Dihydroartemisinin inhibits macrophages from releasing inflammatory factors TNF-alpha and IL-6 and inflammatory mediators NO by down-regulating iNOS protein. Artemisinin may help dihydroartemisinin to show its anti-inflammatory effect through metabolism.</p>