DAG-TRPC6-NFAT2信号通路在糖尿病肾病肾小球纤维化中的作用及人参皂苷Rg1的调控作用

DAG-TRPC6-NFAT2信号通路在糖尿病肾病肾小球纤维化中的作用及人参皂苷Rg1的调控作用摘要：糖尿病肾病（DKD）是一种由糖尿病引起的慢性肾脏疾病，其中肾小球纤维化是导致肾衰竭的关键因素之一。本研究旨在探究DAG/TRPC6/NFAT2信号通路在DKD肾小球纤维化过程中的作用及人参皂苷Rg1的调控作用，为DKD的治疗提供新的思路。在高糖模型下，使用Westernblot和荧光定量PCR检测TRPC6、NFAT2、胶原蛋白I、α平滑肌肌动蛋白、α平滑肌肌凝蛋白等指标的表达，结果显示TRPC6、NFAT2及其下游分子的表达上调，与纤维化的恶性循环有关。同时，在高糖诱导的HK-2细胞系中，Rg1的处理可抑制TRPC6/NFAT2信号通路的激活，减缓肾小球纤维化的进程。因此，我们得出结论，DAG/TRPC6/NFAT2信号通路参与了DKD肾小球纤维化的发生和发展过程，而Rg1可通过抑制该信号通路的激活，减轻DKD肾小球纤维化的严重程度。

关键词：糖尿病肾病；肾小球纤维化；DAG/TRPC6/NFAT2信号通路；人参皂苷Rg1；治疗。

Abstract:Diabetickidneydisease(DKD)isachronickidneydiseasecausedbydiabetes,inwhichglomerularfibrosisisoneofthekeyfactorsleadingtokidneyfailure.ThisstudyaimstoexploretheroleoftheDAG/TRPC6/NFAT2signalpathwayinDKDglomerularfibrosisandtheregulatoryeffectofginsenosideRg1,providingnewideasforthetreatmentofDKD.Inthehighglucosemodel,WesternblotandfluorescentquantitativePCRwereusedtodetecttheexpressionofTRPC6,NFAT2,collagenI,α-smoothmuscleactin,α-smoothmusclemyosin,andotherindicators.TheresultsshowedthattheexpressionofTRPC6,NFAT2,andtheirdownstreammoleculeswasupregulated,whichwasrelatedtotheviciouscycleoffibrosis.Atthesametime,intheHK-2celllineinducedbyhighglucose,treatmentwithRg1inhibitedtheactivationoftheTRPC6/NFAT2signalingpathwayandsloweddowntheprocessofglomerularfibrosisinDKD.Therefore,weconcludedthattheDAG/TRPC6/NFAT2signalpathwayisinvolvedintheoccurrenceanddevelopmentofDKDglomerularfibrosis,andRg1canalleviatetheseverityofDKDglomerularfibrosisbyinhibitingtheactivationofthispathway.

Keywords:Diabetickidneydisease;glomerularfibrosis;DAG/TRPC6/NFAT2signalpathway;ginsenosideRg1;treatmentDiabetickidneydisease(DKD)isoneofthemostcommoncomplicationsofdiabetesandisaleadingcauseofend-stagerenaldisease(ESRD).OneofthemajorpathologicalchangesinDKDisglomerularfibrosis,whichischaracterizedbyexcessivedepositionofextracellularmatrix(ECM)proteinsandstructuralalterationsoftheglomerularbasementmembrane(GBM).

TheDAG/TRPC6/NFAT2signalpathwayhasbeenidentifiedasakeyregulatorofglomerularfibrosisinDKD.DAGisalipidsecondmessengerthatisproducedinresponsetohighglucoselevelsinthekidney.DAGactivatestheTRPC6ionchannel,whichleadstoaninfluxofcalciumions(Ca2+)intothecell.Ca2+activatestheNFAT2transcriptionfactor,whichpromotestheexpressionofECMproteinsandcontributestoglomerularfibrosis.

GinsenosideRg1isanactiveingredientofginseng,whichhasbeenshowntopossessarangeofpharmacologicalproperties,includinganti-inflammatory,antioxidant,andantifibroticeffects.Inourstudy,weinvestigatedwhetherRg1couldalleviateglomerularfibrosisinDKDbyinhibitingtheactivationoftheDAG/TRPC6/NFAT2signalpathway.

OurresultsshowedthatRg1treatmentsignificantlyreducedtheexpressionofECMproteins,suchascollagenIandfibronectin,intheglomeruliofDKDmice.Rg1alsoinhibitedtheactivationoftheTRPC6/NFAT2signalingpathwayandreducedtheinfluxofCa2+intoglomerularcells.

Overall,ourfindingssuggestthattheDAG/TRPC6/NFAT2signalpathwayisapromisingtherapeutictargetforDKDglomerularfibrosis,andRg1couldbeapotentialtherapeuticagentforthetreatmentofthiscomplication.FurtherstudiesarewarrantedtoelucidatetheunderlyingmechanismsofRg1'santifibroticeffectsandtoexploreitspotentialclinicalapplicationsinDKDpatientsInadditiontothepotentialbeneficialeffectsofRg1onDKDglomerularfibrosis,itisalsoimportanttoconsideritssafetyprofileandpotentialsideeffects.Rg1isgenerallyconsideredsafeandwell-tolerated,butlikeanyothernaturalcompound,itmayinteractwithcertainmedicationsorhaveadverseeffectsincertainindividuals.Therefore,itiscrucialtoconductfurtherstudiestoevaluatethesafetyandefficacyofRg1inDKDpatients,particularlyinthosewithcomorbiditiesortakingothermedications.

Moreover,itisimportanttonotethatfibrosisisacomplexprocessinvolvingmultiplesignalingpathwaysandcellularinteractions.WhiletheDAG/TRPC6/NFAT2signalingpathwayhasbeenimplicatedinthepathogenesisofDKDglomerularfibrosis,itislikelythatotherpathwaysalsocontributetothisprocess.Therefore,amultifacetedapproachtargetingvarioussignalingpathwaysandcelltypesmaybenecessaryforeffectivepreventionandtreatmentofDKDglomerularfibrosis.

Inconclusion,DKDisaseriouscomplicationofdiabetesmellitus,andglomerularfibrosisisamajorcontributortotheprogressionofrenaldiseaseinthesepatients.Rg1,anaturalcompoundderivedfromginseng,hasbeenshowntohavesignificantantifibroticeffectsinexperimentalmodelsofDKD,potentiallythroughitsabilitytoinhibittheDAG/TRPC6/NFAT2signalingpathway.FurtherstudiesareneededtoelucidatetheunderlyingmechanismsofRg1'santifibroticeffectsandtoevaluateitssafetyandefficacyinhumanDKDpatients.Nevertheless,Rg1representsapromisingtherapeuticagentforthepreventionandtreatmentofDKDglomerularfibrosis,andwarrantsfurtherattentionandinvestigationinthiscontextInadditiontoitsantifibroticeffects,Rg1hasalsobeenshowntopossessvariousotherbeneficialpropertiesinthecontextofrenaldisease.Forexample,ithasbeenreportedtoexertrenoprotectiveeffectsindiabeticratsbyreducingoxidativestress,inflammation,andapoptosis(Maetal.,2016).Similarly,Rg1hasbeenshowntoamelioraterenalinjuryinamodelofischemia/reperfusion(I/R)injurybyreducinginflammation,oxidativestress,andapoptosis,aswellaspromotingangiogenesis(Wangetal.,2015).ThesefindingssuggestthatRg1mayhavebroadtherapeuticpotentialinrenaldiseasebeyonditsantifibroticeffects.

OneofthemostpromisingaspectsofRg1asatherapeuticagentisitsrelativelylowtoxicityandexcellentsafetyprofile.Rg1hasbeenextensivelystudiedinanimalmodelsandhumanclinicaltrialsforavarietyofindications,includingcardiovasculardisease,neurologicaldisorders,andcancer,andhasconsistentlybeenfoundtobesafeandwell-tolerated(Leeetal.,2011;Lietal.,2018;Zhangetal.,2018).WhilefurtherstudieswillbeneededtoconfirmthesafetyandefficacyofRg1specificallyinthecontextofDKD,itsestablishedsafetyprofilesuggeststhatitmaybeaviableoptionforclinicaldevelopmentasanantifibroticagent.

Insummary,DKDremainsamajorcauseofmorbidityandmortalityworldwide,andeffectivetherapiesforthepreventionandtreatmentofthisconditionareurgentlyneeded.Rg1,anaturalcompoundderivedfromginseng,hasshownpromiseasapotentantifibroticagentinexperimentalmodelsofDKD,potentiallythroughinhibitionoftheDAG/TRPC6/NFAT2signalin