Isorhamnetin Protects Zearalenone-induced Damage via the PI3K/Akt Signaling Pathway in Porcine Granulosa Cells
Abstract Background: Zearalenone (ZEA) is widely derived from moldy cereal grain, which has adverse effects on animal reproduction. In particular, pigs are more sensitive to ZEA-induced toxicity than other animals. Isorhamnetin, a flavonoid has extensive of pharmacological activities. However, little is known about the effects of isorhamnetin on reproduction. Thus, it would be interesting to clarify the effect and the underlying molecular mechanism of isorhamnetin involvement in ZEA-induced cytotoxicity in porcine granulosa cells.Results: Our findings showed that isorhamnetin suppressed ZEA-induced apoptosis by regulating Bcl-2 and Bax protein changes. Changes in intracellular Ca2+ levels and CHOP, ATF6, GRP78 indicated that isorhamnetin rescued ZEA-induced endoplasmic reticulum stress (ERS). Furthermore, isorhamnetin prevented ZEA-induced reactive oxygen species (ROS) via P38 signaling pathway. Mechanistically, isorhamnetin stimulated the expression of PCNA and CyclinD, thereby raising the ratio of S phases cells in response to ZEA-induced apoptosis via PI3K/Akt signaling pathway. Isorhamnetin also recovered ZEA-induced steroidogenesis disorder by regulating steroidogenic enzyme gene and proteins (FSH-R, CYP19A1). Conclusions: Collectively, these findings show that isorhamnetin protects granulosa cells from ZEA-induced damage via the PI3K/Akt signaling pathway, which promotes proliferation, alleviates steroidogenesis disorder, ERS and oxidative stress.