tanshinone-ii-a-sodium-sulfonate and Hypertension--Pulmonary

Recent studies have demonstrated the beneficial effects of STS in treating pulmonary hypertension by inhibiting the pulmonary vascular remodeling and suppressing the abnormally elevated proliferation and migration of PASMCs. However, the roles of STS on pulmonary vascular endothelium remain largely known.. In this study, we investigated the effects and mechanisms of STS on pulmonary vascular endothelial dysfunction by using a chronic hypoxia-induced pulmonary hypertension (HPH) rat model, as well as in primarily cultured rat PMVECs and human ESC-ECs cell models.. Firstly, a 21-day treatment of STS significantly prevents the disease development of HPH by normalizing the right ventricular systolic pressure and right ventricular hypertrophy, improving the cardiac output. Then, STS treatment markedly inhibits the hypoxia-induced medial wall thickening of the distal intrapulmonary arteries. Notably, STS significantly inhibits the hypoxia-induced apoptosis in both the pulmonary endothelium of HPH rats and primarily cultured PMVECs, through the stabilization of BMPR2 protein and protection of the diminished BMP9-BMPR2-Smad1/5/9 signaling pathway. In mechanism, STS treatment retrieves the hypoxic downregulation of BMPR2 by stabilizing the BMPR2 protein, inhibiting the BMPR2 protein degradation via lysosome system, and promoting the plasma membrane localization of BMPR2, all of which together reinforcing the BMP9-induced signaling transduction in both PMVECs and human ESC-ECs. However, these effects are absent in hESC-ECs expressing heterozygous dysfunctional BMPR2 protein (BMPR2. STS may exert anti-apoptotic roles, at least partially, via induction of the BMP9-BMPR2-Smad1/5/9 signaling transduction in pulmonary endothelium and PMVECs.

Topics: Animals; Bone Morphogenetic Protein Receptors, Type II; Cells, Cultured; Endothelial Cells; Human Embryonic Stem Cells; Humans; Hypertension, Pulmonary; Hypoxia; Phenanthrenes; Pulmonary Artery; Rats; Signal Transduction; Smad1 Protein

Our laboratory previously showed that sodium tanshinone IIA sulfonate (STS) inhibited store-operated Ca(2+) entry (SOCE) through store-operated Ca(2+) channels (SOCC) via downregulating the expression of transient receptor potential canonical proteins (TRPC), which contribute to the formation of SOCC (Wang J, Jiang Q, Wan L, Yang K, Zhang Y, Chen Y, Wang E, Lai N, Zhao L, Jiang H, Sun Y, Zhong N, Ran P, Lu W. Am J Respir Cell Mol Biol 48: 125-134, 2013). The detailed molecular mechanisms by which STS inhibits SOCE and downregulates TRPC, however, remain largely unknown. We have previously shown that, under hypoxic conditions, inhibition of protein kinase G (PKG) and peroxisome proliferator-activated receptor-γ (PPAR-γ) signaling axis results in the upregulation of TRPC (Wang J, Yang K, Xu L, Zhang Y, Lai N, Jiang H, Zhang Y, Zhong N, Ran P, Lu W. Am J Respir Cell Mol Biol 49: 231-240, 2013). This suggests that strategies targeting the restoration of this signaling pathway may be an effective treatment strategy for pulmonary hypertension. In this study, our results demonstrated that STS treatment can effectively prevent the hypoxia-mediated inhibition of the PKG-PPAR-γ signaling axis in rat distal pulmonary arterial smooth muscle cells (PASMCs) and distal pulmonary arteries. These effects of STS treatment were blocked by pharmacological inhibition or specific small interfering RNA knockdown of either PKG or PPAR-γ. Moreover, targeted PPAR-γ agonist markedly enhanced the beneficial effects of STS. These results comprehensively suggest that STS treatment can prevent hypoxia-mediated increases in intracellular calcium homeostasis and cell proliferation, by targeting and restoring the hypoxia-inhibited PKG-PPAR-γ signaling pathway in PASMCs.

Topics: Animals; Calcium Signaling; Cell Proliferation; Cells, Cultured; Cyclic GMP-Dependent Protein Kinases; Disease Models, Animal; Dose-Response Relationship, Drug; Hypertension, Pulmonary; Hypoxia; Male; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Phenanthrenes; PPAR gamma; Protein Kinase Inhibitors; Pulmonary Artery; Rats, Sprague-Dawley; RNA Interference; Time Factors; Transfection; TRPC Cation Channels; Vascular Remodeling

To investigate the effect of sodium tanshinone IIA sulfonate (STS) on rat right ventricular systolic pressure (RVSP), mean right ventricular pressure (MRVP), right ventricular hypertrophy index [RV/(LV+S)], pulmonary vascular remodeling, and PPARγ protein expression in pulmonary artery smooth muscle of monocrotaline (MCT) induced rat pulmonary hypertension model.. The pulmonary hypertension model was established by subcutaneously injection of MCT, and the rats were treated with or without STS for 21 days. After that, RVSP, mRVP and RV/(LV+S) were measured. Lung histopathological sections were prepared, and the lumen area, the wall thickness and arterial radius of pulmonary arteries were quantified using the Image Pro Plus 6.0 software. PPARγ protein expression in rat pulmonary artery smooth muscle was detected by Western blot.. Compared with control group, the RVSP, mRVP were significantly increased in MCT group (P < 0.05), while in the MCT+STS group, it was decreased from (81.2 ± 1.9) and (28.6 ± 2.0) mmHg to (35.4 ± 8.3) and (14.1 ± 5.4) mmHg, respectively (P < 0.05). The RV/(LV+S) of MCT group was (0.57 ± 0.04), markedly higher than those of control group and control+STS group (0.33 ± 0.02) and (0.34 ± 0.02) , respectively, P < 0.05, while in MCT+STS group, the RV/(LV+S) was (0.43 ± 0.02), lower than that of MCT group (P < 0.05) ;The luminal area/total area of MCT group decreased to (27 ± 6)%compared with control rats (56.00 ± 3.00) % (P < 0.05) . The wall thickness/artery radius (WT%) of MCT group increased from (20 ± 4) % (control group) to (40 ± 3) % (P < 0.05) .In MCT+STS treated rats, luminal area/ total area and WT% were (39.0 ± 2.0) %and (31.0 ± 2.0) %, both statistically different from MCT group (P < 0.05) . The level of PPARγ protein in pulmonary artery smooth muscle of MCT group was (48 ± 4) %, lower than control group (100 ± 0) % (P < 0.05) .In the MCT+STS group, PPARγ protein expression was recovered (102 ± 3) %, (P < 0.05) .. STS markedly decreased RVSP,MRVP, RV/(LV+S) and pulmonary vascular remodeling in MCT induced pulmonary hypertension rat, and PPARγ might be targeted as a key molecule during STS treatment.

Topics: Animals; Hypertension, Pulmonary; Lung; Male; Monocrotaline; Muscle, Smooth, Vascular; Phenanthrenes; PPAR gamma; Pulmonary Artery; Rats; Rats, Sprague-Dawley

Danshen, the dried root of Salvia miltiorrhiza, is widely used in clinics in China for treating various diseases, including cardiovascular diseases. Sodium tanshinone IIA sulfonate (STS), a water-soluble derivative of tanshinone IIA isolated as the major active component from Danshen, was recently reported to be effective in attenuating the characteristic pulmonary vascular changes associated with chronically hypoxic pulmonary hypertension (CHPH); however, the underlying detailed mechanisms are poorly understood. In this study, we investigated the effects of STS on basal intracellular Ca(2+) concentration ([Ca(2+)](i)) and store-operated Ca(2+) entry (SOCE) in distal pulmonary arterial smooth muscle cells (PASMCs) exposed to prolonged hypoxia or isolated from CHPH rats. SOCE measured by Mn(2+) quenching of Fura-2 fluorescence in PASMCs from rats exposed to chronic hypoxia (10% O(2), 21 d) was increased by 59%, and basal [Ca(2+)](i) was increased by 119%; this effect was inhibited by intraperitoneal injection of STS. These inhibitory effects of STS on hypoxic increases of SOCE and basal [Ca(2+)](i) were associated with reduced expression of canonical transient receptor potential (TRPC)1 and TRPC6 in distal pulmonary arterial smooth muscle and decreases on right ventricular pressure, right ventricular hypertrophy, and peripheral pulmonary vessel thickening. In ex vivo cultured distal PASMCs from normoxic rats, STS (0-25 μM) dose-dependently inhibited hypoxia-induced cell proliferation and migration, paralleled with attenuation in increases of basal [Ca(2+)](i), SOCE, mRNA, and protein expression of TRPC1 and TRPC6. STS also relieved right ventricular systolic pressure, right ventricular hypertrophy, and TRPC1 and TRPC6 protein expression in distal pulmonary arteries in a monocrotaline-induced rat model of pulmonary arterial hypertension. These results indicate that STS prevents pulmonary arterial hypertension development likely by inhibiting TRPC1 and TRPC6 expression, resulting in normalized basal [Ca(2+)](i) and attenuated proliferation and migration of PASMCs.

Topics: Animals; Calcium; Calcium Channels; Cell Movement; Cell Proliferation; Drugs, Chinese Herbal; Hemodynamics; Hypertension, Pulmonary; Hypoxia; Male; Muscle, Smooth, Vascular; Phenanthrenes; Phytotherapy; Pulmonary Artery; Rats; Rats, Sprague-Dawley; Salvia miltiorrhiza; Transient Receptor Potential Channels; TRPC Cation Channels

To investigate the effect of sodium tanshinone IIA sulphonate (STS), a water-soluble derivative of tanshinone II A, on hypoxic pulmonary hypertension (HPH) in rats and its underlying mechanisms.. Rats were exposed to hypoxia for two or three weeks, pretreated with or without STS. We detected mean pulmonary arterial pressure (mPAP), the ratio of right ventricle weight to left ventricle with septum weight [RV/(LV+S)], wall thickness and voltage-activated potassium channel (Kv) 2.1 mRNA level of pulmonary arteries (PAs), respectively, and the in vitro effects of STS on proliferation and Kv2.1 expression of cultured pulmonary smooth muscle cells (PASMCs) from normal rats. Cell proliferation was determined by 3-(4,5-dimethylthiazal-2-yl)-2,5-diphenyltetrazoliumbromiede (MTT) assay and direct cell counting. Kv2.1 mRNA and protein level were evaluated by reverse transcription-polymerase chain reaction and Western blot, respectively.. Chronic hypoxia increased values of mPAP and RV/(LV+S) and inhibited Kv2.1 mRNA level in PAs. Three weeks' daily STS pretreatment inhibited the hypoxia-induced increased mPAP and RV/(LV+S), pulmonary arterial thickening and up-regulated Kv2.1 mRNA level in PAs. Further study in vitro showed that STS suppressed significantly hypoxia-induced PASMCs proliferation and inhibition of Kv2.1 expression in PASMCs.. STS might play protective effects on HPH through decreasing mPAP, V/(LV+S) and inhibiting structural remodeling in distal PAs. The mechanism of these effects may be attributed to inhibiting PASMCs proliferation and stimulating Kv2.1 expression.

Topics: Animals; Cells, Cultured; Dose-Response Relationship, Drug; Hypertension, Pulmonary; Hypoxia; Male; Molecular Structure; Myocytes, Smooth Muscle; Phenanthrenes; Pulmonary Artery; Random Allocation; Rats; Rats, Sprague-Dawley; Shab Potassium Channels