Effect Of Diminazene On Lipid Metabolism In Rats With Non-Alcoholic Fatty Liver Disease Induced By High-Fat Diet

Non-alcoholic fatty liver disease(NAFLD)is a clinical pathological synthesis that excludes liver fatty degeneration caused by excessive drinking or other clear damage to the liver,or is characterized by significant liver fat accumulation Sign.Diminazene(DIZE),as an activator of ACE2,can activate the RAS compensation pathway.It has been widely used in clinical treatment of diseases such as pulmonary hypertension,but its role in NAFLD has not been reported.This experiment explored the effect of DIZE on lipid metabolism and biochemical mechanism of NAFLD rats induced by high-fat diet.The experiment includes the following aspects:1.Effect of DIZE on non-alcoholic fatty liver disease induced by high-fat dietThe role of ACE2 activator DIZE in NAFLD rats induced by high-fat diet was explored.In the study,6-week-old male SPF SD rats were selected.Eight rats were randomly selected and fed with common feed as a blank group.The remaining rats were fed with high-fat feed for modeling.After 4 weeks,24 NAFLD rats with successful modeling were randomly divided into 3 groups,and continued to be fed with high-fat diet and treated according to the following methods:1)Model group:intragastric administration of normal saline;2)DIZE group:irrigation Stomach 15mg/kg·d DIZE;3)Lovastatin group(LOV group):Gavage 15mg/kg·d lovastatin.The blank group continued to be fed with common feed,and the same amount of normal saline was intragastrically administered.During the period,orbital blood was collected every 2 weeks,and the content of triglyceride(TG)and total cholesterol(TC)in plasma was determined.After the glucose tolerance test at week 10,all rats were sacrificed,blood was collected,and the contents of biochemical indexes such as TG,TC,HDL-C,LDL-C,ALT,AST,NEFA,AKP,LDH,and TBA were determined.Take the liver,weigh and measure the liver organ index,and take the liver tissue from the same site to make histopathological sections.Results:1)The NAFLD rat model was successfully established.The model rats showed increased body weight and liver index,significantly increased blood lipid levels,severe insulin resistance and hepatic steatosis.2)Compared with the model control group,intragastric DIZE can effectively reduce the body weight and liver index of NAFLD rats,improve insulin resistance,significantly increase the content of HDL-C in plasma of NAFLD rats,and significantly reduce the plasma TG,TC,The content of ALT,AST,NEFA,AKP,LDH and TBA.3)Histopathology of the liver shows that DIZE can significantly reduce the fat deposition in liver cells and improve the steatosis of rat liver cells.Conclusion:Gavage DIZE can obviously alleviate insulin resistance and hepatic steatosis induced by high-fat diet in NAFLD rats,and its related mechanism needs further study.2.DIZE protects liver damage by changing the balance of the two RAS pathwaysTo study the effect of DIZE on the activation of ACE2 in the liver of NAFLD rats and its effect on the balance of the RAS classic pathway and the compensation pathway.The experiment grouping and processing are the same as the previous chapter.The collected liver is used for the following experiments:ELISA method is used to detect the content of AngⅡ and Ang1-7 in liver tissue homogenate,and the change of AngⅡ/Ang1-7 ratio is analyzed;Western blot method was used to detect the change of ACE2 expression in liver tissue,and Western blot method was used to detect the expression level of ACE,ACE2,AT1R and MasR protein in liver tissue of each group of rats,and the change of ACE/ACE2 ratio was analyzed.Results:1)Compared with the blank group,the expression levels of ACE2 gene and protein in the DIZE group were significantly increased;2)The expression of ACE/ACE2 in the liver of NAFLD rats was unbalanced.Significantly increased,both ACE and ATIR proteins were up-regulated,ACE2 protein expression was down-regulated.DIZE intragastrically significantly increased the protein expression levels of ACE2 and MasR,and reduced the content of AngⅡ in liver tissue,down-regulated the protein expression levels of ACE and AT1R,and significantly reduced AngⅡ/in liver tissue of NAFLD rats The ratio of Ang1-7 and ACE/ACE2.Conclusion:DIZE can effectively activate ACE2,and high levels of ACE2 produce Angl-7 by degrading AngⅡ,which makes RAS compensation pathway dominant,and improves insulin resistance and liver fat deposition in NAFLD rats induced by high-fat diet feeding.ACE2 plays an important role in the development of NAFLD lipid metabolism disorders.3.A preliminary study on the biochemical mechanism of ACE2/DIZE regulating liver lipid metabolism disorder in non-alcoholic fatty liver disease ratsThe research in the previous chapter found that DIZE alleviated steatosis and fat deposition in the liver of NAFLD rats by activating ACE2.This chapter will explore the biochemical mechanism of ACE2’s effect on liver lipid metabolism.The experimental grouping and processing are the same as Chapter 3,taking the collected liver to determine the content of TG,TC,HDL-C,LDL-C and NEFA in liver tissue homogenate;RT-qPCR method to detect lipid synthesis and catabolic pathway in liver MRNA expression of key enzymes and regulatory factors;Western blot method was used to detect the protein expression levels of lipid metabolism regulatory factors SREBP1 and PPAR in liver tissues.Results:1)The content of TG,TC and NEFA in the liver tissue of the model group was significantly increased,and the content of HDL-C and LDL-C increased but there was no significant difference.Compared with the model group,the contents of NEFA and LDL-C in the liver tissues of rats in the DIZE group were significantly or significantly reduced,and the contents of HDL-C increased significantly.The TC content decreased but there was no significant difference.2)The key enzymes of lipid synthesis ACC 1,FAS,SCD-1 and ME and the regulatory factor SREBP-lc in the liver tissue of the model group were up-regulated;the key enzyme of lipid catabolism CPT-1,CPT-2,HSL and ACO,and the regulatory factor PPARa genes were all down-regulated.3)DIZE can significantly reduce the protein expression level of SREBP1 in the liver tissue of NAFLD rats,and up-regulate the protein expression level of PPAR.CONCLUSION:Disturbance of lipid metabolism occurs in liver tissue of NAFLD rats.Exogenous stimulant DIZE can inhibit fatty acid synthesis and stimulate fatty acid decomposition by activating the endogenous ACE2 present in the liver,thereby improving steatosis and fat deposition in NAFLD rat liver.In summary,the exogenous stimulant DIZE can activate the endogenous ACE2 in the liver by induction.The activated ACE2 exerts certain anti-hepatic steatosis and other damage effects by affecting the liver lipid metabolism process,and has a certain treatment for NAFLD.effect.DIZE has a similar effect to the anti-fatty liver drug LOV,that is,the experimental results provide a theoretical basis for the development of DIZE as a new NAFLD therapeutic drug.