ABSTRACT
Objective To observe the effect of different hypoxic time on hydrogen sulfide (H2S), nitric oxide (NO) and Ras homolog gene family,member A/Rho associated coiled coil-forming kinase(RhoA-ROCK) pathway in rat cerebrovascular endothelial cells(EC),and investigate the effect of dermatogenous H2S on the RhoA-ROCK pathway. Methods Rat brain vascular EC was cultured by collagenase digestion. The EC was measured for H2S and NO after hypoxia for 1,2,4,8 and 24 h respectively. G-LISA was used to detect RhoA activity. Proteins expression changes were detected by Western blot. Results After 1 hour of hypoxia,the content of H2S decreased significantly, the NO content decreased significantly after hypoxia of 4 hours,the activity of RhoA increased significantly after hypoxia of 8 h. The expression of CSE protein decreased significantly after 4 h of hypoxia,the expression level of eNOS protein decreased significantly after 8 h of hypoxia,and the expression of ROCK1 and ROCK2 increased significantly at 8 h of hypoxia. Both endogenous and exogenous H2S inhibited RhoA activity. Conclusion During the hypoxic injury of rat cerebrovascular endothelial cells. The decrease of endogenous H2S occurred first, followed by NO,and the activation of RhoA-ROCK pathway occurred later,which may be secondary to the decrease of H2S.
ABSTRACT
<p><b>Objective</b>To investigate the potential role of the RhoA/Rock signaling pathway in the formation of prostate cancer and the effects of the Rock inhibitor fasudil on the invasion, migration and apoptosis of human prostate cancer cells.</p><p><b>METHODS</b>Human prostate cancer cell lines PC3 and DU145 were treated with fasudil at the concentrations of 5, 10, 20, 40, 80, and 160 μmol/L, respectively, and those as negative controls cultured in the Ham's-F12 medium, all for 24 hours. Then, MTT assay was used to measure the cell inhibition rate and half maximal inhibitory concentration (IC50) value of fasudil, with 1/4 of IC50 as the medication dose for further investigation. The expressions of RhoA, RockⅠ, and RockⅡ proteins in the PC3 and DU145 cells were detected by Western blot and immunohistochemistry, and the invasion, migration and apoptosis of the cells were determined using the Transwell chamber, scratch wound healing assay and flow cytometry.</p><p><b>RESULTS</b>Fasudil inhibited the proliferation of the PC3 cells from (9.29±1.23)% at 5 μmol/L to (81.37±3.97)% at 160 μmol/L and that of DU145 from (7.59±1.54)% to (76.53±2.67)%, both in a dose-dependent manner (P<0.05 ). Significantly fewer PC3 and DU145 cells migrated into the lower compartment in the experimental group (39.2±8.4 and 34.2±6.7) than in the negative control (116.8±9.3 and 112.5±10.8) (P<0.05 ). The wound healing rates of the PC3 and DU145 cells were remarkably lower in the former (［37.26±1.17］% and ［32.38±2.73］%) than in the latter (［78.12±4.16］% and ［69.47±6.71］%) (P<0.05 ). Annexin V-FITC/PI double staining showed markedly increased apoptosis rates of PC3 and DU145 cells treated with fasudil (［31.88±2.49］% and ［28.65±2.99］%) as compared with the negative controls (［7.51±2.28］% and ［7.13±1.61］%) (P<0.05 ). The expressions of RockⅠ and RockⅡ were significantly reduced in the fasudil-treated cells in comparison with those of the control group (P<0.05 ) while that of RhoA showed no significant difference between the two groups (P>0.05 ).</p><p><b>CONCLUSIONS</b>The RhoA/Rock signaling pathway may play an important role in the formation of prostate cancer. Fasudil can significantly inhibit the proliferation, migration, and invasion and promote the apoptosis of human prostate cancer PC3 and DU145 cells by reducing RhoA/Rho kinase activity.</p>
Subject(s)
Humans , Male , 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine , Pharmacology , Apoptosis , Cell Line, Tumor , Cell Movement , Cell Proliferation , Prostatic Neoplasms , Drug Therapy , Pathology , Signal Transduction , rho-Associated KinasesABSTRACT
The hepatic portal system is a unique circulatory system that connects two systems of capillary beds ; one in the wall of the small intestine and spleen and the second in the sinusoidal area of the liver.Therefore,alterations in vasoreactivity (vasodilation and vasoconstriction) play a critical role in the pathophysiology of portal hypertension (PHT).The RhoA/ ROCK pathway exerts an important role in the Ca2+-independent mechanism in vascular smooth muscle (VSM).This mechanism not only modulates the constriction of intrahepatic small vessels and hepatic stellate cells (HSCs) but also effects the hyperdynamic circulation due to vascular hyporesponsiveness.Understanding the detailed mechanism and role of the RhoA/ROCK signal pathway in portal hypertension could be of great utility in providing a new target for portal hypertension therapy.
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ObjectiveTo explore the control factor of pulmonary microvascular endothelial cells in pulmonary hemorrhage with the RhoA-Rock pathway inhibitors.MethodsHuman pulmonary rnicrovascular endothelial cells were conventionally cultured,and were divided into four groups:control group,inhibitor group,hypoxia group and hypoxia group with inhibitor.As different fluorescein lsothiocyanate-phalloidin and filamentous actin (F-actin) in cytoplasm combined,it issued red fluorescence.We observed the dynamic changes of F-actin by laser scanning confocal microscope in hypoxia human pulmonary microvascular endothelial cells and recorded the value of fluorescence.ResultsThe mean fluorescence intensity of F-actin of hypoxia group in 1 h,12h and 24 h was (64.3 ±5.5)％,(60.3±4.2)％,and (47.8 ±4.6)％ as compared with the control group;the ratio of hypoxia group with inhibitor was (66.2 ±3.2)％,(67.1 ±6.2)％,and (72.5 ± 6.1 ) ％ as compared with the control group.The mean fluorescence intensity of F-actin decreased obviously after 1 h hypoxia treated to cells,decreasing to (64.3 ± 5.5 ) ％ of the control group (P ＜0.05 ) ;to 24 h,decreasing to (47.8 ±4.6) ％ of the control group(P ＜0.05).The mean fluorescence intensity of F-actin decreased to (66.2 ± 3.2) ％ of the control group after 1 h hypoxia treated in inhibitor group,which was more than 1 h in the hypoxic group.F-actin decreased obviously to (72.5 ± 6.1 ) ％ of the control group after 24 h hypoxia treated in inhibitor group.There was significant difference comparing with the hypoxia group after 24 h hypoxia(P ＜0.05).The mean fluorescence intensity of F-actin of inhibitor group without anoxic was invariant comparing with the control group(P ＞0.05).Cortex-like structure disappeared and the stress fibers arranged disorderly after hypoxia.Actin depolymedzated and broke gradually with the extension of hypoxia time.If to be hypoxic after pretreated with RhoA-Rock pathway inhibitor,cortex-like structure by the composition of pednuclear F-actin reappeared,distribution and arrangement of stress fibers in the cytoplasm tended to rule.ConclusionThe RhoA-Rock pathway mediates the damage on F-actin of pulmonary microvascular endothelial cells after hypoxia.Interfering with the RhoA-Rock pathway inhibitors can provide a new direction for the treatment of neonatal pulmonary hemorrhage.