Oxytocin may promote hippocampal neurogenesis in ischemic stroke rats via a pathway related to DNMT1-mediated Wnt3a/β-catenin

DNA methylation plays a pivotal role in neuroprotection after ischemic stroke. Oxytocin, a neuropeptide renowned for its involvement anti-inflammatory and antioxidant activities, emerges as a promising candidate for the treatment of stroke. Here, we employed a transient middle cerebral artery occlusion (tMCAO) rat model to explore the underlying mechanisms of oxytocin's therapeutic potential. We utilized the Morris Water Maze, novel object recognition, and intruder tests to assess spatial memory, cognitive memory, and social memory abilities in rats, respectively. RNA sequencing and Western blotting were employed to detect alterations in mRNA expression and protein expression levels in the hippocampus. Daily oxytocin administration (0.1 and 1.0 mg/kg, subcutaneous) for seven days significantly reduced infarct volume, restored the expression of 1100 genes, including NQO1 and HO1, and robustly promoted hippocampal neurogenesis in tMCAO rats. These effects translated into enhanced neurological function and improved learning and memory abilities. Remarkably, our findings reveal that oxytocin-induced neurogenesis is intimately linked to the activation of the Wnt3a/β-catenin signaling pathway with Nrf2 as a key downstream target. Furthermore, it is possible that oxytocin, acting through its receptors, inhibited the tMCAO-induced binding of DNMT1 to MeCP2, thereby preventing the increase in DNA methylation at the Wnt3a gene. In summary, our study implies a possible involvement of oxytocin in the activation of the DNMT1-mediated Wnt3a/β-catenin signaling pathway. It may contribute to enhancing hippocampal neurogenesis and ameliorating memory impairments in rats with ischemic stroke. This hints that oxytocin holds great promise as a potential therapeutic agent for promoting post-stroke neurogenesis.