RESUMO
Hyperlipidemia is a dyslipidemia caused by dyslipidemia of lipid metabolism， which can be divided into primary and secondary types. The current clinical diagnostic criteria are mainly changes in lipid levels， which are the inducers of high-risk cardiovascular diseases such as atherosclerosis， pancreatitis and coronary heart disease. As a key target in lipid metabolism， peroxisome proliferator-activated receptor α （PPARα） is involved in a variety of metabolic activities， including fatty acid degradation， synthesis， transport， storage， lipoprotein metabolism， etc. Activation of PPARα can maintain the balance of lipid metabolism through a variety of ways， which is an important way to treat hyperlipidemia. At present， chemical drugs such as statins and bettes are mainly used in the clinical treatment of hyperlipidemia. Although they can slow down the disease to a certain extent， there are many adverse reactions and drug resistance. By reviewing the literature in recent years， the author found that the activation of PPARα pathway by traditional Chinese medicine in the treatment of hyperlipidemia has significant effect and small adverse reactions. The lipid-lowering active ingredients include flavonoids， alkaloids， phenols， terpenoids and other compounds. These active components mainly affect the expression of downstream effectors through the activation of PPARα pathway， thereby inhibiting the synthesis of total cholesterol and promoting fatty acid oxidation， and play a role in the treatment of hyperlipidemia. In this paper， we systematically reviewed the structure types and mechanism of active components of traditional Chinese medicine that activate PPARα pathway， so as to provide guidance for the rational development and clinical application of lipid-lowering traditional Chinese medicine new drugs.
RESUMO
OBJECTIVE： To study the effects of selenium-enriched Ganoderma lucidum crude extract on lipid metabolism， liver function and inflammatory response in type 2 diabetic model rats. METHODS： Totally 120 rats were randomly divided into normal control group （n＝20， normal saline） and model group （n＝100）. Normal control group was fed with normal diet， and model group was fed with high-fat diet. 4 weeks later， model group was given intraperitoneal injection of Streptozotocin solution （30 mg/kg） to induce T2DM model. After modeling， 90 rats were randomly subdivided into model control group （normal saline）， positive control group （metformin， 200 mg/kg） and selenium-enriched G. lucidum crude extract low-dose， medium-dose and high-dose groups （300， 600， 1 200 mg/kg， calculated by extract）， with 18 rats in each group. They were given medicine intragastrically， once a day， from Monday to Saturday. Half of rats in each group were selected 4， 8 weeks after medication； the serum levels of glucose and insulin were detected， and islet resistance index were calculated. The serum levels of liver function indexes （AST， ALT， AKP）， blood lipid indexes （FFA， TC， TG， LDL-C） and inflammatory factors （TNF-α， IL-6， IL-1β） were detected by ELISA. After HE staining， the histopathological changes of liver tissue were observed by microscopy. mRNA and protein expressions of peroxisome proliferator activated receptor α （PPARα） and peroxidase acyl coenzyme A oxidase 1 （ACOX1） in liver tissue were detected by RT-qPCR and Western blot assay. RESULTS： Compared with normal control group， glucose， insulin serum levels and islet resistance index were significantly increased （P＜0.01）； serum liver function indexes， blood lipid indexes and inflammatory factor levels of model control group were increased significantly in model control group after 4 and 8 weeks medication （P＜0.05 or P＜0.01）. The hepatocyte swelling of model control group was round and the volume was significantly larger than that of blank control group. The liver had different degrees of steatosis and vacuolization， accompanied by a small amount of inflammatory cell infiltration. mRNA and protein expressions of PPARα and ACOX1 in liver tissue were decreased significantly （P＜0.05 or P＜0.01）. Compared with model control group， except that there was no significant decreased in islet resistunce index and AST， ALT， IL-6， IL-1β serum levels after 4 weeks of medication， and glucose， insulin， ALT serum levels after 8 weeks of medication and the levels of 4 blood lipid indexes after 4 and 8 weeks of medication in selenium-enriched G. lucidum crude extract low-dose group （P＞0.05）， above serum indexes of other groups were decreased significantly after 4 and 8 weeks of medication （P＜0.05 or P＜0.01）. After 4 and 8 weeks of medication， the pathological changes of liver tissue in rats were alleviated in varying degrees. protein and mRNA expressions of PPARα and ACOX1 in liver tissue were increased significantly after 4 and 8 weeks of medication （P＜0.05 or P＜0.01）. CONCLUSIONS： Selenium-enriched G. lucidum crude extract can up-regulate protein and mRNA expressions of PPARα and ACOX1 in liver tissue， promote the excretion of accumulated fatty acid and significantly improve fatty acid metabolism， inflammatory response and liver function in T2DM model rats.
RESUMO
AIM@#The potential of Trifolium pratense (red clover) extract in the prevention of lipid disorder has attracted increasing attention in recent years. In this study, the aim was to determine whether and how red clover extract affected the development of murine diet-induced non-alcoholic steatohepatitis.@*METHODS@#Non-alcoholic steatohepatitis was induced in C57BL/6 mice by feeding mice with a methionine-choline-deficient (MCD) diet. Hematoxylin and eosin staining was used for histological analyses. Real-time PCR was used to analyze the mRNA expression levels.@*RESULTS@#Hepatic steatosis and necroinflammation was observed in MCD diet-fed mice, and this diet-induced steatosis was significantly attenuated, whereas liver inflammation was not significantly attenuated, by red clover extract treatment. Consistent with the results of H&E staining, the MCD diet-induced increase of liver triglycerides and cholesterol levels were significantly reduced by red clover extract treatment. However, with the improvement in hepatic steatosis, mRNA levels of acetyl CoA oxidase, carnitine palmitoyl transferase-1, and liver fatty acid-binding protein, three genes regulated by peroxisome proliferator-activated receptor (PPAR) α, were unaffected.@*CONCLUSION@#Red clover extract alleviated MCD diet-induced hepatic steatosis, but did not ameliorate liver inflammation in C57BL/6 mice, and the improvement in hepatic steatosis was not through activating PPARα.