The P300-ARRDC3 axis participates in maternal subclinical hypothyroidism and is involved in abnormal hepatic insulin sensitivity in adult offspring

Highlights•Maternal subclinical hypothyroidism (SCH) affects glucose metabolism in offspring.•RNA-seq revealed increased ARRDC3 expression in the liver of SCH offspring.•Reduced phosphorylation levels of Akt, GSK-3β, and FoxO1 and elevated expression levels of G6Pase and PEPCK were observed in SCH offspring.•Overexpression of ARRDC3 suppressed the Akt/GSK-3β/FoxO1 pathway in Hepa1-6 cells.•Maternal SCH enhanced acetylation of the ARRDC3 promoter via increased P300 expression.•P300-ARRDC3 pathway mediates decreased insulin sensitivity in offspring of maternal SCH by modulating the Akt/GSK-3β/FoxO1 signaling pathway.AbstractNumerous studies have suggested potential associations between maternal subclinical hypothyroidism (SCH) and adverse metabolic outcomes in offspring, however, the underlying mechanism remains unclear. In this study, we generated a maternal SCH mouse model by administering 50 ppm 6-propyl-2-thiouracil (PTU) in the drinking water of pregnant mice until delivery. This model was used to investigate the mechanisms influencing glucose metabolism in offspring. RNA sequencing (RNA-seq) revealed a substantial increase in ARRDC3 expression in the livers of the offspring of the SCH model mice, which may contribute to insulin resistance. Additionally, the phosphorylation levels of key proteins in the insulin signalling pathway, such as protein kinase B (Akt), glycogen synthase kinase 3 beta (GSK-3β), and Forkhead box protein O1 (FoxO1), were correspondingly reduced in the SCH offspring. Moreover, overexpression of ARRDC3 in Hepa1‒6 cells suppressed the Akt/GSK-3β/FoxO1 signalling pathway and increased the expression of glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK), which was consistent with the molecular changes observed in SCH offspring. Our results also indicated that the upregulation of ARRDC3 in SCH offspring may result from increased H3K27 acetylation of the ARRDC3 promoter region, driven by elevated expression of P300. Importantly, adequate L-T4 supplementation during pregnancy improved insulin sensitivity and reversed the molecular alterations in the insulin signalling pathway observed in SCH offspring. In conclusion, exposure to intrauterine SCH resulted in altering the P300-ARRDC3 axis in offspring and impaired insulin sensitivity by disrupting the Akt/GSK-3β/FoxO1 signalling pathway. Timely L-T4 supplementation during pregnancy is an effective strategy to prevent insulin resistance in offspring of SCH mothers. This study elucidates potential molecular mechanisms behind insulin resistance in SCH offspring and suggests novel therapeutic targets for treating metabolic disorders related to maternal SCH.