ABSTRACT
Objective To investigate the effect of smoking and smoking cessation on the phosphorylation of IKK-β in type 2 diabetic rats. Methods Forty-two six-week-old Wistar rats were randomly divided into 4 groups: normal control(NC, n =7), diabetes control (DC, n =7), diabetes with smoking (DS, n = 14) and diabetes with smoking cessation(SC, n = 14). Rats in DS and SC groups were further assigned randomly into 8w and 12w subgroups. DS group was given passive smoking twice a day for 8 or 12 weeks, while SC group ceased passive smoking for 4 weeks after 8 or 12 weeks of smoking . Western blot method was used to detect the level of IKK-13 phosphorylation in skeletal muscle. Results Compared with the NC group,the phosphorylation of IKK-β protein in DC group was increased (0. 16±0. 05 vs 0. 30±0. 08, P < 0. 01). There was an increasing trend with the phosphorylation level of IKK-β in the DS (8w) subgroup, but there was no statistical difference between the DC group and SC(8w) subgroup (0. 40±0. 09 vs 0. 30±0. 08,0. 36±0. 10, P >0. 05). The phosphorylation level of IKK-β in DS(12w) group increased obviously, being significantly higher than that in the DC group and SC (12w) subgroup(0. 74 ± 0. 11 vs 0.30±0.08,0.35±0.07,P < 0.01). Conclusion With the prolongation of smoking duration, the phosphorylation of IKK-β in type 2 diabetic rats increased. After smoking cessation, the phosphorylation of IKK-β decreased. The phosphorylation of IKK-β may be involved in the mechanism by which smoking causes type 2 diabetes.