Direct inhibitory effect of flaxseed on porcine ovarian granulosa cell functions

Abstract

Flaxseed is useful as a functional food and alternative medicine owing to its beneficial health effects. Its action on ovarian cell functions and interrelationships with the upstream hormonal regulators remain unknown. Our aim was to examine the direct influence of flaxseed extract on basal porcine ovarian functions (proliferation, apoptosis), leptin release, and response to insulinlike growth factor I (IGF-I). First, we examined the effect of flaxseed extract on the accumulation of proliferation (PCNA) and apoptosis (bax) marker and on leptin release in cultured porcine ovarian granulosa cells. Next, granulosa cells were cultured with IGF-I with and without flaxseed extract and analyzed for PCNA and bax accumulation by quantitative immunocytochemistry, whereas leptin was analyzed by RIA. Flaxseeds decreased the accumulation of proliferation marker and increased that of the apoptosis marker at all doses and reduced leptin output at 100 µg/ml. On the contrary, IGF-I promoted PCNA and suppressed bax. Flaxseed did not modify IGF-I action on these parameters.Thus, we showed flaxseed action on porcine reproductive processes, with a direct effect on the ovary and flaxseed ability to affect ovarian cell proliferation, apoptosis, and leptin release. Furthermore, we confirmed the pro-proliferating and anti-apoptosis action of IGF-I, but indicated that flaxseed action on ovarian cell proliferation and apoptosis are not due to changes in their response to IGF-I. The potential direct anti-reproductive action of flaxseed needs to be considered during its application in nutrition, medicine, and animal production. Page 2 of 18 https://mc06.manuscriptcentral.com/apnm-pubs Applied Physiology, Nutrition, and Metabolism D r a f t 3

Influence of Flaxseed (Linum usitatissimum) on Female Reproduction

“…In rats, flaxseed suppressed the production of anti-Mullerian hormone by ovarian cells [32]. Flaxseed reduced leptin levels in womenʼs plasma [52] and leptin release by cultured porcine ovarian granulosa cells [53].…”

“…The addition of flaxseed extract decreased proliferation (accumulation of proliferation marker PCNA) and increased cytoplasmic apoptosis markers (accumulation of Bax) in cultured human ovarian granulosa cells 27 , 43 revealed the ability of a flaxseed diet to induce the apoptosis of chicken ovarian cancer cells. The reported action of flaxseed on intracellular regulators of proliferation and apoptosis in healthy 12 , 53 and cancer 24 , 27 , 43 , 45 ovarian cells suggests that its influence on ovarian state and cell turnover could be mediated by its influence on ovarian cell proliferation: the apoptosis rate.…”

“…In vivo experiments of Dixit et al [27,43] revealed the ability of a flaxseed diet to induce the apoptosis of chicken ovarian cancer cells. The reported action of flaxseed on intracellular regulators of proliferation and apoptosis in healthy [12,53] and cancer [24,27,43,45] ovarian cells suggests that its influence on ovarian state and cell turnover could be mediated by its influence on ovarian cell proliferation: the apoptosis rate.…”

The effects of natural products and bioactive ingredients of traditional Chinese medicine on apoptosis of ovarian granulosa cells

“…Meanwhile, administration of high dose of capsaicin at 100, 150, and 200 μM induced GC apoptosis in 24 and 48 h (Güler & Zik, 2018). Flaxseed ( Linum usitatissimum L.) was reported to decrease the accumulation of proliferating cell nuclear antigen and increase expression of Bax at 1, 10, and 100 μg/ml and reduce leptin output at 100 μg/ml (Štochmal'ová et al, 2019).…”