Search

The aim of the study was to compare the effects of weekly personal feedback, based on objectively measured physical activity, on daily sleep in breast cancer survivors (BCS) with those of an intervention that also included online supervised physical exercise sessions (OSPES). BCS benefiting from both personal feedback and OSPES (n = 24), from pre-lockdown (T0) to the first month (T1) of the national lockdown, experienced an increase in both total (p ≤ 0.001) and restorative (p ≤ 0.001) sleep time, inverting their trend from the first month of lockdown to its end (total sleeping time T1 vs. T2 0.01 ≤ p <.001, T1 vs. T3 p ≤ 0.001; restorative sleeping time T1 vs. T2 0.05 ≤ p <.01, T1 vs. T3 p ≤ 0.001). Supportive technology, together with the reception of weekly tailored advice and OSPES seems to improve both quality and quantity of sleep. [ABSTRACT FROM AUTHOR]

Due to the association of hormone replacement therapy (HRT) with breast cancer risk, estrogenically active soy isoflavones are considered as an HRT alternative to alleviate menopausal symptoms. However, several recent reports challenged the health benefits of soy isoflavones and associated them with breast cancer promotion. While glyconic isoflavones are the major constituents of soybean seeds, due to their low cell permeability, they are considered to be biologically inactive. The glyconic isoflavones may exert their effects on membrane-bound estrogen receptors or could be converted to aglycones by extracellular b-glucosidases. Therefore, we hypothesized that despite their low cell permeability, soybean cultivars with high glyconic isoflavones may promote breast cancer cell growth. To test this, composition and estrogenic activity of isoflavones from 54 commercial soybean cultivars were determined. Soybean seeds produced in identical climate and growth conditions were used to minimize the effects of extraneous factors on isoflavone profile and concentrations. The glyconic daidzin concentration negatively correlated with genistin and with other aglycones. Relative to control, isoflavone extracts from 51 cultivars were estrogenic and promoted the growth of estrogen receptor positive (ERC) breast cancer cell line MCF-7 from 1.14 to 4.59 folds and other three cultivars slightly reduced the growth. Among these, extracts from three cultivars were highly estrogenic and promoted MCF-7 cell growth by 2.59-4.64 folds (P<0.005). Among six isoflavones, daidzin was positively associated with MCF-7 cell growth (P<0.005, r D 0.13966), whereas the negative correlation between genistin and MCF-7 cell growth was nearly significant (P≤0.0562, r = -0.026141). Furthermore, in drug interaction studies daidzin-rich isoflavone extracts antagonized tamoxifen, an ER+ inhibitor. Taken together, our results suggest that the glyconic daidzin-rich soy isoflavone extracts may exert estrogenic effects and promote ER_ breast cancer growth. [ABSTRACT FROM AUTHOR]

Genistein, a major soy isoflavone having weak estrogenic activities, has been suggested to reduce the risk of breast cancer incidence. However, many studies have yielded inconsistent results. We investigated the effects of dietary genistein on the development of breast cancer using ethyl methanesulphonate (EMS) chemically induced rat model of hormone-dependent mammary carcinoma. Female Wistar King A rats were orally given EMS for 12 wk and fed isoflavone-free NIH-07PLD diets with or without genistein, beginning immediately after weaning period. All EMS-treated rats fed either diet developed estrogen and/or progesterone receptor-positive mammary carcinoma by 24 wk. The addition of either low or high genistein, which produced the plasma concentrations comparable with those observed in humans consuming high soy diets, did not show any preventive activity. Soy-containing pellet food, exhibiting substantial plasma concentrations of isoflavones such as genistein, daidzein, equol, and glycitein, significantly increased the latency periods, compared to either NIH-07PLD diet with low (P = 0.027) or high (P = 0.034) genistein. Body weights, total EMS uptakes, and urinary estradiol concentrations were not significantly different among groups. These data indicate that genistein does not exert clear preventive effects and that isoflavone components other than genistein might be preventive against hormone-dependent mammary carcinogenesis. [ABSTRACT FROM AUTHOR]