Aquaporin-4 gene silencing protects injured neurons after early cerebral infarction.
Aquaporin-4 regulates water molecule channels and is important in tissue regulation and water transportation in the brain. Upregulation of aquaporin-4 expression is closely related to cellular edema after early cerebral infarction. Cellular edema and aquaporin-4 expression can be determined by measuring cerebral infarct area and apparent diffusion coefficient using diffusion-weighted imaging (DWI). We examined the effects of silencing aquaporin-4 on cerebral infarction. Rat models of cerebral infarction were established by occlusion of the right middle cerebral artery and siRNA-aquaporin-4 was immediately injected via the right basal ganglia. In control animals, the area of high signal intensity and relative apparent diffusion coefficient value on T2-weighted imaging (T2WI) and DWI gradually increased within 0.5-6 hours after cerebral infarction. After aquaporin-4 gene silencing, the area of high signal intensity on T2WI and DWI reduced, relative apparent diffusion coefficient value was increased, and cellular edema was obviously alleviated. At 6 hours after cerebral infarction, the apparent diffusion coefficient value was similar between treatment and model groups, but angioedema was still obvious in the treatment group. These results indicate that aquaporin-4 gene silencing can effectively relieve cellular edema after early cerebral infarction; and when conducted accurately and on time, the diffusion coefficient value and the area of high signal intensity on T2WI and DWI can reflect therapeutic effects of aquaporin-4 gene silencing on cellular edema.
Department of Radiology, Affiliated Haikou Hospital of Xiangya School of Medicine, Central South University (Department of Radiology, Haikou Municipal People's Hospital), Haikou, Hainan Province, China.
Zhan-Ping
ZP
He
Department of Radiology, Affiliated Haikou Hospital of Xiangya School of Medicine, Central South University (Department of Radiology, Haikou Municipal People's Hospital), Haikou, Hainan Province, China.
Hong
H
Lu
angioedema; aquaporin-4; cerebral ischemia; cytotoxic edema; diffusion-weighted imaging; gene silencing; magnetic resonance imaging; middle cerebral artery occlusion; nerve regeneration