The Change Of Zinc Transporters In Cardiac Hypertrophy And The Effects And Mechanism Of Zinc On Cardiac Hypertrophy

ObjectiveTo study whether zinc transporters changes in cardiac hypertrophy and to explore protective effects and underlying mechanism of zinc on cardiac hypertrophy.MethodsA cell model of hypertrophy was achieved based on Ang II induced H9C2 cardiac cell in this study.In addition,an animal model of hypertrophy was established in a rat with abdominal aortic constriction(AAC).the Real-Time PCR analysis were used to determine the m RNA expression level of hypertrophy markers(ANP??-MHC)and the mRNA expression level of zinc transporters.To assess the role of zinc in cardiac hypertrophy,Wistar rats are divided into four groups:-Sham and normal diet group,AAC and normal diet group(AAC+N),AAC and high-zinc diet group(AAC+H)and AAC and low-zinc diet group(AAC+L).At the end of experiment,the mice were sacrificated and the hearts were taken photos.Heart weight-to-body weight ratios(HW/BW),left ventricle weight-to-body weight ratios(LVW/BW),heart weight-to-tibia length ratios(HW/TL)and left ventricle weight-to tibia length ratios(LVW/TL)were recorded at the time of tissue collection was used to evaluate cardiac hypertrophy.Real-Time PCR analysis were used to determine the mRNA expression level of hypertrophy markers(ANP ??-MHC).The protein levels of I?B-? and NF?B was detected by western-blot assay.Results1.The mRNA levels of Zip8 and Zip14 were significant increased in AngII induced cardiomyocyte hypertrophy.2.The mRNA levels of Zip8,Zip11 and Zip14 were significant increased and ZnT6 was significant decreased in AAC induced cardiac hypertrophy.3.Compared to the Sham group,the HW/BW,LVW/BW,HW/TL and LVW/TL were significantly increased in rats with AAC+N for 6 weeks.Compared to the AAC+N group,high-zinc diet significantly decreased the HW/BW,LVW/BW,HW/TL and LVW/TL,whereas AAC+L group prevented this,indicating that supplemental zinc inhibited cardiac hypertrophy induced by AAC.4.Compared to the Sham group,AAC significantly decreased I?B-? protein levels and increased NF?B protein levels.Compared to the AAC+N group,high-zinc diet significantly increased I?B-? protein levels and decreased NF?B protein levels,whereas AAC+L group prevented this,indicating that supplemental zinc inhibited cardiac hypertrophy through inhibiting the expression of NF?B.5.Compared to the Sham group,AAC significantly increased nuclear NF?B protein levels.Compared to the AAC+N group,high-zinc diet significantly decreased nuclear NF?B protein levels,whereas AAC+L group prevented this,indicating that supplemental zinc inhibited cardiac hypertrophy through inhibiting the nuclear translocation of NF?B.Conclusions1.Zip8 and Zip14 mRNA levels were significant increased in AngII induced cardiomyocyte hypertrophy2.Zip8,Zip11 and Zip14 mRNA levels were significant increased and ZnT6 mRNA levels was significant decreased in AAC induced cardiac hypertrophy.3.Supplemental zinc can inhibit cardiac hypertrophy induced by AAC4.Zinc inhibited cardiac hypertrophy through inhibiting the expression and the nuclear translocation of NF?B.