The P2X7 Receptor Involved in gp120-Induced Cell Injury in BV2 Microglia

Abstract

This study was aimed at exploring the effects of P2X7 receptor on BV2 microglia cell injury induced by glycoprotein gp120 (gp120) and its underlying mechanisms. We used the MTS method to study the influence of different gp120 concentrations on BV2 microglia cells, and to test the degree of cell injury in each gp120 treatment group; quantitative real-time PCR (qPCR) and Western blot were used to detect the P2X7 mRNA and receptor protein expressions. Immunocytochemistry and Western blot were used to detect the P2X7 receptor expression and P65 NF-κB, respectively. We also measured the content of TNFα, IL-1β, nitric oxide (NO) and reactive oxygen species (ROS). We found that the cell survival rate generally decreased as gp120 concentration increased, and the cell survival rate of the gp120 + Brilliant Blue G (BBG) group was higher than that of the gp120 group. Western blot and qPCR results showed that the expressions of P2X7 receptor protein and mRNA were positively dose-dependent with gp120 concentration; the results of immunocytochemistry and Western blot showed that the expressions of P2X7 receptor and P65 NF-κB in the gp120 group increased significantly compared to those of the control (Ctrl) group, but those in the gp120+BBG group decreased. Taken together, these results confirmed that the P2X7 receptor is involved in gp120-induced BV2 microglial cell injury and that the underlying mechanism may be associated with the over-activation of microglia caused by P2X7 receptor up-regulation, which leads to abundant release of inflammatory factors which exert toxic effects on the cells.

Keywords: BV2 microglia; Cell injury; P2X7 receptor; gp120.