Construction Of The Express System Carrying Full Length Cdna Fragment Coding Mouse Klotho Protein And The Mechanisms Of Attenuating Hypertention Progression And Heart Damage In Spontaneous Hypertensive Rats

Objective: To construct the recombinant plasmids of pAAV.mKL, todetect KL expression in COS-7. The constructs of AAV vector pAAV-mKLwas then packaged in AAV-293with pHelper and pAAV.RC to producerAAV.mKL. The SHRs were transfected with rAAV.mKL, to study theimpact of KL on blood pressure, myocardial hypertrophy and myocardialfibrosis, to provide the experiment foundation for the gene therapy inhypertention and heart injury.Methods:(1) Total mRNAs were extracted from mouse kidney tissue,the full length of mouse KL cDNA were obtained by RT-PCR and clonedinto pAAV-HnGFP recombinant plasmids. The recombinant plamids weretransfected into COS-7eukaryotic expression cells, and the KL expressionin COS-7cells were detected by fluorescent microscopy, RT-PCR andImmunofluorescence and ELISA;(2) The pAAV-mKL was then transfected into AAV-293with pHelper and pAAV.RC to produce rAAV.mKL;(3)Transfect SHRs with rAAV.mKL, to study the impacts of KL in bloodpressure, myocardial hypertrophy and myocardial fibrosis.Results:(1) The full length of mouse KL cDNA was obtained byRT-PCR, the pAAV.mKL was constructed successfully, the KL expression inCOS-7cells were increased;(2) The rAAV.mKL was produced afterpAAV-mKL transfected into AAV-293with pHelper and pAAV.RC. ThemKL cDNA was amplified from rAAV.mKL DNA;(3) The KL proteinprevents progression of hypertension, decreases heart mess index, inhibitsmyocardial hypertrophy and myocardial fibrosis.Conclusion: The pAAV.mKL could increase the expression of KL inCOS-7cell.The transfection of rAAV.mKL in SHRs prevents progression ofhypertension, decreases heart mass index, and inhibits myocardialhypertrophy and myocardial fibrosis. The KL plays an important role inpreventing progression of spontaneous hypertension and its heart damages.