Task: Question Answering
Input (English): Context: TGF-1 regulates bone metabolism and mediates bone turnover during postmenopause. Sclerostin negatively regulates Wnt signaling pathway and also has an important role in postmenopausal bone loss. Little is known about the relationship between serum TGF-1 and sclerostin during menopause. We compared serum levels of TGF-1 and sclerostin in pre- and postmenopausal women and assessed the potential correlations of these levels with each other and with serum levels of bone turnover markers and bone mineral density. A total of 176 women (58 premenopausal, 62 early postmenopausal, and 56 late postmenopausal) were included in this study. Serum TGF-1 level was significantly higher in early postmenopausal women compared with premenopausal (32.07.19 vs. 26.556.67 ng/ml, p=0.01) and late postmenopausal (32.07.19 vs. 28.657.70 pg/ml, p=0.031) women, and no significant differences in serum sclerostin levels were observed among the 3 groups. There was a significant negative correlation between TGF-1 and sclerostin in early postmenopausal women, but not in other groups of women. Based on multiple regression analysis, only TGF-1 (=-0.362; p=0.007) was an independent predictor of sclerostin during early postmenopause. Our findings suggest that serum TGF-1 level increases during postmenopause and declines in old age. Sclerostin production is inhibited by TGF-1 during early postmenopause. 
 Question: Sclerostin regulates what process?
Output (English): bone metabolism