Cell apoptosis and proliferation in rat brains after intracerebral hemorrhage: role of Wnt/β-catenin signaling pathway

Background/aim: To investigate the role of Wnt/β-catenin signaling pathway in cell apoptosis and proliferation in intracerebral hemorrhage (ICH) in rats. Materials and methods: The ICH rats were established by stereotaxic infusion of 50 μL autologous arterial blood into the right striatum. Pathological characteristics of brain tissue was assessed by hematoxylin and eosin and TUNEL staining, and the expressions of proliferating cell nuclear antigen (PCNA) and Wnt3a/β-catenin/cyclin D1 were investigated by immunohistochemistry or reversetranscription polymerase chain reaction. Results: The number of apoptotic cells and PCNA-positive cells kept increasing from the day following the ICH induction and reached a peak on the 3rd and 14th days, respectively. Some of the PCNA-positive cells could coexpress neurofilament protein-200 or glial fibrillary acidic protein. Wnt3a, β-catenin, cyclin D1, and PCNA mRNAs reached maximal expression levels on the 3rd, 7th, 7th, and 14th days, respectively. Moreover, the number of apoptotic cells was significantly positively correlated with the expressions of Wnt3a and β-catenin mRNAs, and negatively correlated with the number of PCNA-positive cells. Conclusion: Our results suggest that the Wnt/β-catenin signaling pathway is associated with cell apoptosis and expression of PCNA in the ICH rat brain and regulates the balance between cell apoptosis and proliferation.