The sperm quality in DIO male mice is linked to the NF-κB signaling and Ppp2ca expression in the hypothalamus

Emerging studies have reported a significant correlation between obesity and a decline in sperm quality among males, however, the underlying mechanism remains elusive. In this study, we observed that male mice with diet-induced obesity (DIO) exhibited functional alteration in the hypothalamic-pituitary-gonadal (HPG) axis, as evidenced by disruption of luteinizing hormone (LH) pulse release. This alteration was attributed to the activation of nuclear factor kappa B subunit (NF-κB) signaling in the hypothalamus, which subsequently led to a decline in sperm quality. The application of RNA-seq analysis in the hypothalamic arcuate nucleus (ARC) of DIO male mice has revealed a signaling network implicating protein phosphatase 2 catalytic subunit alpha (Ppp2ca), which is involved in the disruption of LH pulse secretion. Activation of NF-κB signaling increased expression, which decreased the Kiss1 expression through inhibition of Akt kinase (AKT) and cAMP responsive element binding protein 1 (CREB1) activities. Overexpression of the Ppp2ca gene in the hypothalamic ARC resulted in disrupted LH pulse secretion patterns and reduced sperm quality. Collectively, our findings provide novel insights into the molecular mechanisms underlying the decline in sperm quality observed in male DIO mice.