DMH1

Zearalenone (ZEA) is a common mycotoxin found in crops that poses a threat to human health, particularly the female reproductive system. Here, we show that exposing mouse zygotes to ZEA in vitro significantly impairs embryo development, leading to embryo arrest. Remarkably, treatment of ZEA-exposed mouse embryos with melatonin significantly improved the blastocyst rates from approximately 40 % to nearly 80 %. Furthermore, melatonin effectively mitigates the harmful effects of ZEA exposure by reducing reactive oxygen species (ROS) levels, preventing mitochondrial dysfunction, and decreasing cell apoptosis. Following embryo transplantation, the birth rate of offspring increased markedly from 7.2 % to 23.62 %. Further research revealed that the abnormal elevation of bone morphogenetic protein 4 (BMP4) signaling induced by ZEA exposure, coupled with the inhibition of the downstream mitogen-activated protein kinase (MAPK) signaling pathway, contributes to developmental blockade in ZEA-exposed mouse embryos. Melatonin rescued ZEA-induced defects in mouse embryo development by inhibiting BMP4 signaling and regulating the MAPK pathway. Moreover, the Bmp4 inhibitor Noggin or its receptor inhibitor DMH-1 could also effectively ameliorate the ZEA-induced impairment of embryo development. Taken together, these findings underscore the potential of melatonin as a therapeutic intervention for addressing the adverse effects of ZEA exposure on mouse embryos.

To improve the efficiency of induced differentiation of primitive neural epithelial cells derived from human induced pluripotent stem cells (hiPSCs-NECs) into functional midbrain dopaminergic progenitor cells (DAPs).

HiPSCs were cultured in mTeSR^TM medium containing DMH1 (10 μmol/L), SB431542 (10 μmol/L), SHH (200 ng/mL), FGF8 (100 ng/mL), purmorphamine (2 μmol/L), CHIR99021 (3 μmol/L), and N2 (1%) for 12 days to induce their differentiation into primitive neuroepithelial cells (NECs). The hiPSCs-NECs were digested with collagenase Ⅳ and then cultured in neurobasal medium supplemented with 1% N2, 2% B27-A, BDNF (10 ng/mL), GDNF (10 ng/mL), AA, TGF-β, cAMP, and 1% GlutaMax in the presence of different concentrations of Rho kinase inhibitor Y27632, and the culture medium was changed the next day to remove Y27632. Continuous induction was performed until day 28 to obtain DAPs.

Human iPSCs expressed the pluripotency markers OCT4, SOX2, Nanog, and SSEA1 and were positive for alkaline phosphatase staining. The hiPSCs-NECs were obtained on day 13 in the form of neural rosettes expressing neuroepithelial markers SOX2, nestin, and PAX6. In digested hiPSCs-NECs, the addition of 5 μmol/L Y27632 significantly promoted survival of the adherent cells, increased cell viability and the proportion of S-phase cells (P < 0.01), and reduced the rate of apoptotic cells (P < 0.05). On day 28 of induction, the obtained cells highly expressed the specific markers of DAPS (TH, FOXA2, NURR1, and Tuj1).

Treatment with Y27632 (5 μmol/L) for 24 h significantly promotes the survival of human iPSCs-NECs during their differentiation into DPAs without affecting the cell differentiation, which indirectly enhances the efficiency of cell differentiation.