ABSTRACT
Objective To explore the effect of hydrogen sulfide (H2S) on the expression of survivin in PC12 cells and the neuroprotective function of H2S on PC12 cells.Methods Different concentrations of sodium hydrosulfide (NaHS) were used to treat the PC12 cells at different times.Dose-effect (50-800 μmol/L) and time-effect (0-180 min) on the expression of survivin were evaluated by Western blotting.Cell viability was tested by using cell counter kit-8.Results NariS treatment at the concentrations from 50 to 200 μmol/L for 30 min could up-regulate the expression of survivin in a dose dependent manner,however,when the concentration of NariS was above that,the expression of survivin decreased gradually;when the concentration of NariS reached 800 μmoi/L,the expression level of survivin was lower than the normal level.Treatment with 400 μmol/L NariS within the range of 0-60 min could promote the expression of survivin in a time dependent manner,but with the extension of time,the expression of survivin was declined.On the other hand,400 μmol/L NaHS preconditioning could enhance the expression of survivin promoted by CoCl2 and reduce the injuries of PC12 cells induced by CoCl2 to increase the cell viability.Conclusion H2S increases the expression ofsurvivin in a dose and time dependent manners at certain degree,which may be related to the protection of PC12 cells against chemical hypoxic damage.
ABSTRACT
<p><b>OBJECTIVE</b>To explore the effect of extracellular signal regulated kinase 1/2 (ERK1/2) on edaravone (EDA)-triggered protection against myocardial toxicity induced by isoprenaline (ISO) in H9c2 myocardial cells (H9c2 cells).</p><p><b>METHODS</b>H9c2 cells were exposed to ISO at different concentrations to establish a cardiac toxicity model induced by persistent excitation of β1 receptor. EDA was added before ISO as a pretreatment. PD-98059, an ERK1/2 inhibitor, was administered 1 h prior to EDA to inhibit the phosphorylation of ERK1/2. Cell viability was measured using cell counter kit (CCK-8). The expressions of p-ERK1/2 and t-ERK1/2 were tested by Western blotting. Mitochondrial membrane potential (MMP) was detected by Rhodamine123 (Rh123) staining and photofluorography.</p><p><b>RESULTS</b>Exposure of H9c2 cells to 80 µmol/L ISO for 24 h down-regulated ERK1/2 phosphorylation and repressed MMP. Pretreatment with 10-40 µmol/L EDA for 1 h inhibited ISO-induced myocardial toxicity and pretreatment of 40 µmol/L EDA partially rescued ERK1/2 phosphorylation and MMP level. PD-98059 abolished cardiac protection of EDA, leading to myocardial toxicity and MMP loss.</p><p><b>CONCLUSION</b>EDA can protect H9c2 cells against myocardial injury induced by ISO by suppressing ISO-triggered inhibition of ERK1/2 activation.</p>