Lentivirus-Mediated Gene Silencing of Lymphocyte Function-Associated Antigen 1 Inhibits Apoptosis of Hippocampal Neurons in Rats with Acute Cerebral Ischemia After Cerebral Lymphatic Blockage

Abstract

Cerebral ischemia is considered to be the most common cause of stroke with high mortality. It occurs as a result of the damage of the hippocampal neurons with lymphocyte function-associated antigen (LFA)-1 being emphasized to play a role in the biological functions of hippocampal neurons. This study was conducted in order to investigate the effects of specific knockdown of LFA-1 expression by lentivirus had on the apoptosis of the hippocampal neurons, simulated by rat models of acute cerebral ischemia after cerebral lymphatic blockage. A total of 60 Wistar rats were selected as subjects, among which 50 were used to establish models of the acute cerebral ischemia after cerebral lymphatic blockage, while the remaining 10 rats were treated with the sham operation. The underlying regulatory mechanisms regarding LFA-1 were analyzed with the treatment of si-LFA-1 and LFA-1 vector in the hippocampal CA1 area of brain tissues isolated from the rats with acute cerebral ischemia. The brain water content, electrolyte content, and blood-brain barrier permeability located in ischemic area of rats were measured. TUNEL staining and immunochemistry methods were employed in order to determine the apoptosis rate and positive levels of LFA-1, MMP-9, and Caspase-3. The mRNA and protein levels of related genes were also detected by means of RT-qPCR and western blot assay. The brain water content, Na+ and Ca+ contents, blood-brain barrier permeability, apoptosis rate, positive levels of LFA-1, MMP-9, and Caspase-3 were decreased, and the K+ content was increased in ischemic tissues treated with si-LFA-1. The mRNA and protein levels of LFA-1, MMP-9, Caspase-3, and Bax had all decreased, while the mRNA and protein levels of Bcl-2 were elevated in the hippocampal CA1 area of rat brain tissues treated with si-LFA-1. These situations could be reversed through the up-regulation of LFA-1. In conclusion, LFA-1 gene silencing could improve the acute cerebral ischemia after cerebral lymphatic blockage by inhibiting apoptosis of the hippocampal neurons in rats.