The Pyk2/MCU Pathway in the Rat Middle Cerebral Artery Occlusion Model of Ischemic Stroke

Publication date: Available online 12 September 2017
Source:Neuroscience Research
Author(s): Kun Zhang, Jiajia Yan, Liang Wang, Xinying Tian, Tong Zhang, Li Guo, Bin Li, Wang Wang, Xiaoyun Liu
Mitochondrial dysfunction caused by Ca²⁺ overload plays an important role in ischemia-induced brain damage. Mitochondrial calcium uniporter (MCU), located on the mitochondrial inner membrane, is the major channel responsible for mitochondrial Ca²⁺ uptake. Activated proline-rich tyrosine kinase 2 (Pyk2) can directly phosphorylate MCU, which enhances mitochondrial Ca²⁺ uptake in cardiomyocytes. It has been suggested that the Pyk2/MCU pathway may be a novel therapeutic target in stress-induced cellular apoptosis. In this study, we explored the role of the Pyk2/MCU pathway in the ischemic brain following a stroke injury. We found that the Pyk2/MCU pathway is activated in a rat cerebral ischemia model, and is responsible for mitochondrial dysfunction and neuronal apoptosis. Inhibiting the Pyk2/MCU pathway with a Pyk2 inhibitor (PF-431396) prevented mitochondrial Ca²⁺ overload, mitochondrial injury, proapoptotic protein release, and cell death. Interestingly, human urinary kallidinogenase (HUK) alleviated neuronal ischemic injury by inhibiting the Pyk2/MCU pathway, suggesting that the Pyk2/MCU pathway may be a protective target for ischemic stroke treatment.



http://ift.tt/2wYYJ4d