The Clinical Study Of Renoprotective Effect Of Peroxisome Proliferator-Activated Receptorγ Agonist And Polymorphism And Transcription Level Of PPAR γ2 Gene

Background: With the morbidity of diabetes mellitus rasing, accompanied that all kinds of complications increased, Diabetic nephropathy is the most common chronic microvascular complications of Type 2 diabete mellius, and the main cause of End Stage Real Disease(ESRD), at the same time one of the reasons that lead the diabetic people to be ill and disability. A lot of researches indicated that the pathogenesy of diabete mellitus was very complicated, refer to biochemistry metabolism, immunity, clotting mechanism, genetic factor and so on. Peroxisome proliferator-activated receptor gamma (PPARγ) was the one member of nuclear hormone superfamily, it binded with ligands and regulated gene transcription, had very closed relation with the metabolism of sugar, lipid and enegy. Up to date, people have discovered that PPARγ play very important action at differentiation of adipocytes, regulation of lipid metabolism, and insulin sensibility. The more recently introduced PPARβγ synthetic agonists thiazolidinediones(TZDs) include rosiglitazone or glitazones were used as the therapeutic alternatives of Type 2 diabete mellitus. Now, more and more investigations manifested that thiazolidinediones not only low blood glucose, but also improve metabolism of glucose and lipid, depress blood pressure, improve vessel Endothelium function, decrease lots of complications and so protect target organs. Therefore, this experiment on the ground of preliminary researches, investigated PPARγ synthetic agonists thiazolidinediones renoprotective action and possible mechanism, and PPARγ2 gene polymorphism assocation with diabetic nephropathy and the distinction of PPARγ2 transcription level.Materials and methods : Collect Harbin medical university endocrine ward, renal ward patients and health examination center healthy people in 2005 and 2006.The diagnosis of Diabetete mellitus : it was according to the diagnostic criteria publicated by WHO in 1999: with the diabetic symptoms, twice and more FPG= 7.0 mmol/L; with the diabetic symptoms ,at any time blood glucose=11.1mmol/L or OGTT 2h blood glucose=11.1mmol/L; without diabetic symptoms, except FPG=7.0mmol/L and OGTT 2h blood glucose=11.1mmol/L [or at any time blood glucose=11.1mmol/L],also other time FPG=7.0mmol/L or OGTT 2h blood glucose=11.1mmol/L.The diagnosis criteria of diabetic nephropathy : diabetic family history; repeated three times observation UAE=30mg/d; urine was major of proteinuria, haematuria was rare; with Retinopathy;without of these criteria, with renal biopsy confirmed.The diagnosis criteria of healthy control subjects:no family history of diabete, hyperte-nsion,with case history,examination, biochemistry, hemanalysis, urinalysis,and ECG, X ray , depleted all kinds diease of heart, cerebral vessels,diabetes, cacergasia of liver and renal.The criteria of depletion: serious hypertension(SBP>160mmHg,DBP>100mmHg); serious metabolic disorder of lipid;diabete complicated with acute complications; in the near future (a month) infectiom,fever,potation and surgical trauma; chronic cardiac failure, unstable angina pectoris,acute myocardial infarction,cerebral apoplexy; serious cacergasia of liver and renal and malignant tumor.All of the diabetic nephropathy patients were divided into two group (medication administration group[MAG] and not[NMAG]) according to whether they use the antidia-betic drug rosiglitazone or not. experiment time limits was 8 weeks, at pre-experiment,4 week and 8 week monitored fast blood glucose(FBG), postmeal blood glucose (PBG),fast insulin (FINS), postmeal insulin (PINS), triglycerides(TG),HDL- cholesterol (HDL-C), LDL- cholesterol(LDL-C),C- peptide(C-P), totalcholesterol(TC), glycosylatedhemoglobin A₁c (HbA_1C), Urine albumin excretion rate, renal function, Creaction protein(CRP), endothelin (ET), plasminogen activetor inhibitor-1 (PAI-1),urine nitric oxide, urine type IV collagen, urine transforming growth factor-beta1, insulin resistance assessed by homeostasis model(HOMA-IR=FBGxFIns/ 22.5, and get its natural logarithm).Accompanied treatment in two groups: on the basis of diet and athletic sports,in orderto decrease the influence of ACEI and ARB to the results, hypotensive drugs select CCB (felodipine),if did not control very added diuretic agent (hydrochlorothiazide)or β-block (metoprolol),aim to control hepertention<140/90mmHg; hypoglucose drugs:gave rosi-glitazone in medication administration group,according to blood glucose two group could use sulphanylureas, biguanides and glucosidase inhibitor, in order to decrease the influence of blood glucose to the results,two group patients blood glucose controlled in the ideal level, the use of traditional Chinese medicine to improve circulation were not controlled.At the same time, selected health people from healthy examination center as control, diabetic patients were divided into single diabete mellitus and diabetic nephropathy, using polymerase chain reaction-restrictive fragment length polymorphism(PCR-RFLP) method to investigate the relation PPARγ2 gene polymorphism with diabetic nephropathy;and real-time PCR examine PPARγ2 transtripation level.Results: In MAG and NMAG,FBG, PBG decreased in 4 week compared to the pre-treament,and remained to finish the experiment,had no statistical value in the two groups . FINS, PINS decreased in 8 week compared to NMAG (P<0.01) ,and the treament time was longer,the level was moer significant (P<0.01) ; otherwise,in Avandia group metabolitic data like TC, TG, HDL-C,LDL-C, HbA1c, C-P varied obviously with the passed ( P<0.05 ) ,among them TG varied more obviously (P<0.01); the influence to systolic blood pressure was increaed with the time passed, and decreased significantly at 8 week(P<0.05 ),had significant statistical value contrasted with the control group( P<0.01 ).But the influence of diastolic blood pressure ,BMI, Cr was not significant in Avandia group(P>0.05) , BMI increased a little, but the difference was not significant (P>0.05) ,the influence of Avandia to UAER exist in earlier peroid (P<0.05) , the time prolonged ,the effect was more obvious (P<0.01) .In Avandia group,at 4 week CRP had no difference compared to pre-experiment,at 8 weeek had significant difference when compared to pre-experiment and control group; PAI- I decreased at 4 week confer to pre-experiment, with statistical value (P<0.05) ,with the time passed,the difference was more obvious; ET decreased when compared to pre-experiment at 8 week( P<0.05 ), more significantly whencompared to the control group (P<0.01) ; urine NO had statistical value at 8 week, more significantly when compared to the control group; urine TGF- β 1 gradually diminished when time went in Avandia group, had statistical value at 8 week compared to the control group and pre-experiment; the varies of urine type IV collagen were not obvious, displayed variability at 8 week, and the control group increased a little.When the patients with diabetic nephropathy developed into IV period,all kinds of datas had no obvious differences when the Avandia group compared to the control group,did not display statistical variability. In diabetic group and diabetic nephropathy group, Ala carriers compared to noncarrier all kinds of biochemical indicators were not different,adjusted with age, sex and smoke, Prol2Al did not have association with diabete and diabetic nephropathy .At the same time,we confirmed that the patients of diabetic nephropathy had the low transcription level confer to the heathy person,the difference had statistic value,diabetic patients increased obviously.Conclusions: Avandia, Peroxisome Proliferator-Activated Receptor γ agonist, depress blood preasure,improve blood glucose ,blood lipid,decrease urine albumin excretion rate.PPAR γ agonist displayed obvious renoprotective action,the mechanism was complicated, it could improve the metabolism of glucose ang lipid, depress blood preasure, protect small vessels endothelium,improve the system activity of blood clotting and fibronolysis, antiinflammation, otherwise the action was more obvious with the time passed, at the early stage the effective was better,so encourage the patients to take the medicine earily; when the patients with the mediate reanl function failure, Avandia did not display significantly renoprotective action, side reaction had no difference compared to the control group,was not necessary to regulate the dose of Avandia.But because of the sample size was small, we needed a biger sample to confirm the results. We confirmed that Prol2Ala had no difference in control case,diabetic nephropathy group and diabete group,In diabetic group and diabetic nephropathy group, Ala carriers compared to noncarrier all kinds of biochemical indicators were not different,Prol2Ala did not have association with diabete and diabetic nephropathy. But because of the sample size was small, weneeded a biger sample to confirm the results.At the same time,we confirmed that the patients of diabetic nephropathy had the low transcription level confer to the heathy person,the difference had statistic value,diabetic patients increased obviously.It suggest that the patients with diabetic nephropathy were gave PPAR γ 2 Agonistand,in order to elevate PPAR γ 2 and increase renoprotective effective.But because of lack of similar expe-riment,the result need to be confirmed.