Abstract:

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 (5.5mmol/L glucose), group B (16.7mmol/L glucose), group C (16.7mmol/L glucose+100μmol/L NaHS) and  group D (5.5mmol/L glucose+100μmol/L NaHS). After treating for 24h, 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(P<0.01)and the mRNA level was also increased in group B(P<0.01). However, COX-2 protein expression was distinctly decreased(P<0.05) as well as mRNA level(P<0.01) 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 (P<0.05), but NaHS could stabilize the cytoplasmic NF-κB protein level (P<0.01). 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.

Key words: High glucose; Hydrogen sulfide; Endothelial cells; Cyclooxygenase-2; Nuclear factor-κB