Mechanisms involved in hydrogen sulfide attenuating high glucose-induced inflammation in endothelial cells

Objective To evaluate the effects of hydrogen sulfide(H2S) on high glucose-induced inflammation of endothelia cells and to explore the possible mechanisms.Methods Human umbilical vein endothelial cells(HUVECs)were randomly divided into 4 groups: group A(5.5 mmol/L glucose),group B(16.7 mmol/L glucose),group C(16.7 mmol/L glucose+100 μmol/L NaHS) and group D(5.5 mmol/L glucose+100 μmol/L NaHS).After treating for 24 h,the expression of nuclear factor-κB(NF-κB) was determined by Western blot,mRNA expression was examined by RT-PCR,and the activation was detected by electromobility shift assay(EMSA).After treating for 48 h,protein and mRNA expressions of cyclooxygenase-2(COX-2) were determined by Western blot and RT-PCR,respectively.Results ① Compared with that of group A,COX-2 protein expression was distinctly increased(P0.01)and the mRNA level was also increased in group B(P0.01).However,COX-2 protein expression was distinctly decreased(P0.05) as well as mRNA level(P0.01) in group C when compared with that of group B.② Compared with that of group A,cytoplasmic NF-κB protein expression was obviously decreased in group B(P0.05),but NaHS could stabilize the cytoplasmic NF-κB protein level(P0.01).There were no significant differences between group A to group D in NF-κB mRNA expression.③ High glucose increased NF-κB activation in group B.Compared with that of group B,decrease in NF-κB activation was observed in group C.There were no differences between group A and group D in NF-κB and COX-2 expressions and NF-κB activity.Conclusion H2S can protect against high glucose-induced inflammation in human umbilical vein endothelial cells,which may be associated with the suppression of COX-2 expression.