Study On Protective Effect Of Oligomeric Proantho Cyanidins Against Cd-induced Diabetic Nephropathy Mice And Its Possible Mechanism

The pathogeny of diabetic nephropathy is complex,almost 20% of diabetic patients will get diabetic nephropathy.In the process of deterioration of diabetes,the increasing of mesangial cells and their outer matrix and the thickness of basement membrane in glomerular structure result in glomerular sclerosis.Metabolomics,which is a simple and stable test method,can effectively capture the changes of metabolites of the organism after stimulation or lesion.It can qualitatively or quantitatively analyze the changes of metabolites in vivo.It is helpful to find potential biomarkers and explore the relevant access of physiological and pathological changes and provide basis to sort of design of therapeutic drugs.In order to construct diabetic nephropathy model,the mice were fed by chromic chloride combined with high fat and sugar diet in this study.The model was verified by physiological and biochemical index,gas chromatography-mass spectrometry measurement technique was used to detect plasma and the metabolite of control group,diabetic nephropathy model group and the oligomeric proantho cyanidins group were analyzed by metabonomics research method to find biomarkers which may induce diabetic nephropathy.The pathogeny of diabetic nephropathy induced by chromic and the protection of oligomeric proantho cyanidins were discussed and provide experimental evidence for clinical diagnosis and medicinal development for diabetic nephropathy.（1）The construction of diabetic nephropathy and detection of physiological and biochemical index.The Cd combined with high fat and sugar diet method was used to construct diabetic nephropathy method.Measuring physiological and biochemical index and observing histomorphology of different groups.The results show that the blood glucose and kidney coefficient of diabetic nephropathy group is obviously higher than that of control group（*P<0.05,*P<0.05）,the weight is obviously lower than control group（***P<0.001）.Compared to control group,the content of TG and TC significantly changed（*P<0.05,*P<0.05）.The HDL-C is obviously lower than control group（*P<0.05）,LDL-C is extremely higher than control group（**P<0.01）.The content of CRE of plasma is extremely higher than control group（***P<0.001）,while the content of CRE is extremely low in urine（**P<0.01）.The content of mALB in urine is extremely higher than control group（**P<0.01）.After OPC treatment,weight,kidney coefficient,TG,TC,LDL-C,CRE of plasma and urine and mALB were significantly enhanced.（2）Plasma metabolite analysis of diabetic nephropathy mice pre-and after OPC treatmentUsing GC-MS test method and metabonomics research method,comparing metabolite of plasma in control group,diabetic nephropathy model group and the oligomeric proantho cyanidins group.The results indicate that the content of galactose,monolinoleoylglycerol and octadecatrienoic acid in diabetic nephropathy model group are obviously lower control group（*P<0.05,**P<0.01,**P<0.01）,while the content of cholesterol is obviously higher than control group（*P<0.05）.After OPC treatment,galactose is obviously higher than model group（#P<0.05）,cholesterol is obviously lower than model group（#P<0.05）,monolinoleoylglycerol and octadecatrienoic acid have not clearly change.（3）Research of pathogeny for diabetic nephropathy miceKidney’s GSH,SOD,PCO,MDA and NO of different groups were detected.The results prove GSH and SOD of model group are clearly lower than control group（*P<0.05,**P<0.01）,PCO and MDA are clearly higher than control group（**P<0.01,**P<0.01）,NO is higher than control group（*P<0.05）.After OPC treatment,compared to model group,the activity of GSH and SOD increase（#P<0.05）and the increasement of PCO and MDA are efficiently compressed（##P<0.01）.Kidney elements Cd²⁺,Cu²⁺,Zn²⁺,Fe²⁺ and Ca²⁺ of different groups were detected.The results prove Cd²⁺,Fe²⁺ and Ca²⁺ of model group are clearly higher than control group（**P<0.01,*P<0.05,**P<0.01）,Cu²⁺ and Zn²⁺ are clearly lower than control group（*P<0.05,*P<0.05）.After OPC treatment,compared to model group,the concentration of Fe²⁺ and Ca²⁺ are notably reduced（#P<0.05,#P<0.05）,while the concentration of Cu²⁺ and Zn²⁺ are remarkably increased（#P<0.05,#P<0.05）.Kidney’s MAPK,ERK,p38,Nrf2,Keap1 and NQO1 protein of different groups were detected.The results prove MAPK and p38 of model group increase（*P<0.05,**P<0.01）,ERK is not significant difference.The amount of Nrf2 decreases（*P<0.05）with the increasing content of Keap1（*P<0.05）,the content of NQO1 increases（**P<0.01）.