A Metabolomics Research On The Mechanism Of Liver Injury Induced By Rosiglitazone

Objective:To explore the toxic mechanism of rosiglitazone on liver injury of hyperglycemic mice,via combination investigation of bile acids homeostasis and hepatic lipidomics.Methods:The study of rosiglitazone induced liver injury on hyperglycemic mice:C57BL/6J mice were divided into three groups: normal diet group(ND),high fat diet group(HFD)and rosiglitazone group(RL).Mice of RL group were given rosiglitazone for 22 weeks after hyperglycemia appeared(HFD treated 16 weeks).ND and HFD groups,mice were given an equal volume of 0.1% CMC-Na.At the end of treatments,all the mice were sacrificed,then liver,gallbladder and serum were collected.Liver histopathology was checked by HE staining.TC,LDL-C,ALT levels in serum were measured by commercially kits.Analysis of bile acids levels and related genes expression: bile acids levels in liver,bile,and serum was measured by UPLC-MS.The One-way ANOVA was used for statistic analysis of bile acids levels,and the principal component analysis method was used for data interpretation.Total RNAs of liver were extracted and sequenced in Beijing Genomics Institute(BGI).46 genes,which were related with bile acids balance regulation,were selected for the analysis of the principal component of rosiglitazone toxicities.Lipidomics analysis in mice liver: The liver lipids were extracted and analyzed by UPLC-MS.Lipids signals were identified using Thermo Lipidsearch 4.2 database,and the principal component analysis was used to setting up lipid libraries.The correlation analysis of lipids and genes expression levels were investigated to exploring the mechanisms of rosiglitazone induced liver injury.Results:1.Hyperglycemic mice were given rosiglitazone for 22 weeks,and the blood glucose,TC,LDL-C levels were decreased significantly,while the ALT levels in serum were significantly increased.HE staining results showed that rosiglitazone reduced blood glucose and lipid levels.Also,rosiglitazone treatments could not reserved liver fat accumulation,which induced by high fat diet.2.14 major bile acids levels in liver,bile,and serum were analyszed,and the results showed that rosiglitazone could significantly alter the levels of various kinds of bile acids.Then,DCA,TCA,and TDCA were indentified as main targets regulated by rosiglitazone by the principal component analysis.18 of the 46 bile acid sinaling pathway related genes were significantly changed,and 7 genes of them exhibited2-fold times changing by transcriptional analysis.3.Liver lipids components of three groups showed significantly difference from each other by the heatmap visualization and principal component analysis,and 412 lipids were changed among liver injury process induced by rosiglitazone.Futher analysis results showed that,46 lipids,which belonged to cell membrane lipids,were identified as related targets to liver injury by rosiglitazone,including 6 ceramides(Cer),11 glycerolipids(DG,TC),and 3 lysolecithins(LPC),1 glycerophosphatidic acid(PA),1 sphingosine(SPH),1 bisphosphatidylglycerol(CL),4phosphoethanolamines(PE),and 8 phosphocholines(PC),2 Phosphatidylserine(PS),4 sphingomyelin(SM),5 phosphatidylglycerol(PG).Thousands of genes was found from transcriptional data analysis,which altered by rosiglitazone,then correlation with 46 cell membrane lipids in necrotic hepatocyte was calculated.Results shwoed that series of genes were associated with hepatocyte necrosis including Ifit3 b,Hrh2,Cyp26a1.These genes may play functions on the lipid metabolism,which would be studied in future.Conclusion:Liver DCA was found as the main factor which mediated liver injury induced by rosiglitazone.Meanwhile,correlation analysis of lipidomics and transcriptomics revealed that bile acid metabolism,immune and inflammatory biological pathways may play founctions in the rosiglitazone induced liver injury,which is meaningful to further investigation.