Investigation of the Effect of Estrogen on DUX4/β-Katenin/PAX3-7 Protein Levels in Facioscapulohumeral Muscular Dystrophy (FSHD)

Abstract

objective: ln Facioscapulohumeral Dystrophy(FSHD) lt is noteworthy that the findings Progressed at an earlier age in men, and the disease worsens in postmenopausal women. DePending on these observations; the role of estrogen was investigated in the pathophysiology of FSHD, Method: primary FSHD1 myoblast cell lines prepared from biopsies of four individuals(63 and 71 Years old(63yM/71yM)two males; 47 and 58 years old(47yFl58yF) two females) were used. Three different groups i) estradiol untreated control group, ii) 10 nM 3O-minutes and iii) 10 nM 4-hours estradiol treatment were generateğ:'Ceil lysİtes from FSHD'myoblasts in these groups were examined bY western blot for the presence-amount of DUX4, PAX3l7 and B-catenin transcription factors. Results: After estradiol treatment DUX4 protein level reduced to zero in 7J-yM, it wasn't detected in 63yM and 47yF, Because of ineffective attachment in 58yF, proteins Weren't obtained. The level of pcatenin protein increased with estradiol in 71yM, 63yM and 47yF samples. 3 different Protein bands of 80 kDa, 55 kDa and 45 kDa were determined f or PAX3l7 proteins. of these, 80 kDa and 56 kDa forms were observed only in 71yM; after estradiol 80-kDa P^X317 form reduced; 56-kDa P^X3/7 form was expressed at the 4th hour. The 45 kDa form was determined in allsamples; with estradioltreatment this form decreased in 71yM-47yF and increased in 63yM, Conclusion: The decrease in DUX4, the increase in B-catenin, stimulation in the exPression of 56 kDa form of P^x3l7 protein family after 4 hours of estradiol treatment support the protective+ole of estrogen in FSHD pathophysiology. To understand the effect of estradiol on pathophysiologY better and to develop treatment alternatives; extensive studies are needed with each transcriPtionfactor and related target genes; both at mRNA-protein levels.