The Effectiveness Of Sodium Tanshinone ⅡA Sulfonate Against Hypoxic Pulmonary Hypertension Through SIRT1-FOXO3a

Objective: To study the effect of sodium tanshinone ⅡA sulfonate(STS)on hypoxic pulmonary hypertension and its related mechanism of action via SIRT1-FOXO3 a signal.Methods: The Sprague-Dawley rats from the experimental center of Hebei Medical University were randomly divided into 3 groups(8 in each group): normoxia,hypoxia,and hypoxia plus STS.The normoxic groups were kept in the air and the others were placed in hypoxic chamber with oxygen concentration of(10±0.5)%.All the rats were fed under the same diet.At 8weeks before modeling,the hypoxia+STS groups were treated with daily intraperitoneal injection of 10mg/kg STS and the other groups received the same dosage of normal saline.After modeling,the mean pulmonary arterial pressure(mPAP),right ventricle hypertrophy index(RVHI)and pulmonary small artery morphology of rats in every group were observed and compared to investigate the effect of STS on HPH.Furthermore,the primary culture of human pulmonary artery smooth muscle cells(hPASMCs)was performed.Cells at passage 5 to 8 were applied in the experiments.The hPASMCs were cultivated for 24 h under normoxia(5%CO2 and 95% air),hypoxia(3%O2,5%CO2 and 92%N2),and hypoxia(3%O2,5%CO2 and 92%N2)interfered with different concentrations of STS(0.1μmol/L,1.25μmol/L,12.5μmol/L and25μmol/L).Then,MTT assays were conducted.The cells were divided into 5groups: normoxia,hypoxia,hypoxia plus STS(25μmol/L),hypoxia plus resveratrol(RE,SIRT1 agonists,40μmol/L)And hypoxia plus STS(25μmol/L)plus nicotinamide(NAM,SIRT1 inhibitor,200μmol/L).Then,MTT assays were conducted.The expression of SIRT1,FOXO3 a and PCNA were detected by Western blot and real-time quantitative RT-PCR.Results:The long-term chronic hypoxia can lead to the increase of RVHIand mPAP(P<0.05),and thicken the media of pulmonary artery in the SD rats.After the intervention of STS,the changes of the above indexes can be significantly reduced and HPH can be improved(P<0.05).In cell experiments,the hypoxia can significantly stimulate the proliferation of hPASMCs(P<0.05).The application of STS and RE,a SIRT1 activator,can up-regulate the expression of SIRT1 and FOXO3 a and reduce the expression of PCNA in h PASMCs(P<0.05).Also,the STS and RE intervention can effectively inhibit the hypoxia induced proliferation of h PASMCs(P<0.05).But,when the SIRT1 inhibitor of NAM is applied,the expression of SIRT1 and FOXO3a was decreased(P<0.05),suggesting that NAM weakened the effects of STS on the proliferation of hPASMCs through SIRT1-FOXO3 a pathway to a certain extent.Conclusions: The long-term chronic hypoxia can cause and aggravate the level of pulmonary hypertension.However,the pulmonary hypertension index can be significantly improved by the treatment of STS.It’s suggested that STS can be effective in preventing and treating HPH in a certain extent.Moreover,the proliferation of PASMCs is inhibited through the pathway of SIRT1-FOXO3 a,which may be one of the mechanisms of the above effect played by the STS.