Effect Of Sulodexide On The Expression Of Podoplanin In Podocytes Of Diabetic Rats

Objective:To observe the expression of podocyte associated moleculesincluding podoplanin, nephrin and podocin on podocytes in diabetic rats andinvestigated the effect of sulodexide on their expression.Methods:Sixty male Spragur–Dawley（SD） rats were randomly dividedinto five groups,normal control group（C）,diabetic group（D）,benazeprilgroup（B）, sulodexide group（S）,and beimzepril combined with sulodexidegroup（B+S）.Diabetes was induced by intraperitoneal injection ofStreptozotocin（STZ，65mg/kg）. The normal control group received injectionsof vehicle only.In the diabetic ones,rats were administered by gavage ofsulodexide(10mg·kg^-1·d^-1)in S group， benazepril(10mg·kg^-1·d^-1)in Bgroup,sulodexide combined with benazepril(10mg·kg^-1·d^-1each)in B+Sgroup,while rats in group C and group D gavaged with equivalent amount ofsaline.At the end of6thand12thweek,the animals were killed and24-hourtotal urine and blood samples were collected to measure urinary totalprotein（UTP）and give hemagglutination analysis.Renal tissues of rats wereharvested for investigate ultrastruction changes by transmission electronmicroscopy and testing the expression of nephrin,podoplanin and podocin byimmunohistochemistry and RT-PCR.Results:（1）At the end of the6thweek,compared to the controlgroup,diabetic rats had increased UTP（65.0±17.22mg/d in groupD,43.4±9.04mg/d in group B,48.4±14.33mg/d in group S and39.83±12.19mg/d in group B+S, P＜0.05）. At the end of the12thweek,diabetic rats had even more UTP excretion compared to those in the6thweek（743.5±150.92mg/d,379.0±49.73mg/d,366±57.00mg/d,293.5±21.38mg/d vs0.33±0.07mg/d,P＜0.05）.Among the diabetic rats, either at the end of the6th week and the12thweek, compared to group D, benapril, sulodexide andbenapril plus sulodexide could decrease UTP, while the combined treatmentgroups got even lower UTP compared to the single treatmentgroups（39.83±12.19mg/d vs43.4±9.04mg/d,48.4±14.33mg/d,293.5±21.38mg/d vs379.0±49.73mg/d,366±57.00mg/d,P＜0.05）.（2）Hemagglutinationstudy showed shortened APTT and higer FIB level in the diabetic groupswhile treatment with sulodexide could improve APTT and FIB（12.25±1.38s,11.4±0.48s vs9.08±0.06s,9.35±0.71s;1.63±0.06g/L,1.69±0.05g/Lvs2.00±0.08g/L,1.91±0.12g/L,P＜0.05）.（3）Ultrastructure study showedthat glomerular basement membrane （GBM） was thicken and podocyte footprocesses wereflatten in group Dcompared with other groups, while B+Sgroup had list lesion.（4）Immunochemistry and RT-PCR studies showed thatthe expression of nephrin、podocin and podoplanin was down-regulated indiabetic groups compared with control group. Treatment with benapril,sulodexide and benapril plus sulodexide could partly restore their expression.This improvement was more significantly in the combined treatment groupthan that of single treatment groups（P＜0.05）.Conclusion:（1） The expressions of podoplanin as well as nephrin,podocin are significantly down-regulated and correlate to podocytes lesion andUTP in diabetic rats. Podoplanin may play a role in podocyte processes fusionand developing urinary protein excretion in diabetic rats.（2） Sulodexide mayimprove podocytes lesion and decrease UTP through restoring the expressionof podocytes associated molecules including podoplanin, nephrin and podocinin diabetic rats.