Twist1 Suppresses The Replicative Senescence Of Human Skin Fibroblasts

Objective:To study the effect and the possible mechanism of Twist1 on the replicative senescence of human skin fibroblasts(HSF)in vitro.Method:1.Human skin fibroblasts(HSF)were extracted by tissue anchored and the replicative senescence model of human skin fibroblasts was established by serial passages.HSF were divided into young group(P3-7)and passage-aged group(P20-25),Senescence-associated-?-gal-staining was used to test the senescence staining rate,the cell proliferation rate was detected by Ed U,and the expression of aging-related protein p21 was measured by Western-blot.These results determined whether the replicative senescence model was successfully established.2.Western-Blot was used to detect the expression of Twist1 in young and passage-aged group.3.Transfected respectively with Si-Twist1 sequence(Si-Twist1 gruop)and its negative control sequence(NC group)in young group,Twist1 protein was downregulated or not by Western-Blot in Si-Twist1 group.The change of Senes-cence-associated-?-gal-staining rate.the cell proliferation rate and p21 protein were detected between Si-Twist1 gruop and NC group.Results:1.Compared with young group,the percentage of positive cells for Senescenceassociated-?-gal-staining was significantly higher,the cell proliferation rate was obviously lower,and the expression of aging-related protein p21 was clearly higher(P<0.05)in passage-aged group.These showed that the replicative senescence model of HSF was successfully established.2.Western-Blot was used to detect the Twist1 protein and the result showed that the expression level of Twist1 protein in young group was evidently higher than that in passage-aged group(P<0.05).3.Senescence-associated-?-gal-staining staining rate was higher,the cell proliferation rate was lower and p21 protein was higher in Si-Twist1 group than in NC group(P<0.05).Conclusion:Twist1 plays a vital role in aging process of HSF,the expression of Twist1 was distinctly down-regulated in passage-aged group.Inhibition of Twist1 expression in vitro can significantly tigger the replicative senescence of HSF and provide a basis for the study of the relationship between Twist1 and senescence of skin fibroblasts.