The effect of chloride channel inhibitor NPPB on proliferation and apoptosis of human trabecular meshwork cells

Objective To study the effect of chloride channel inhibitor NPPB(5-nitro-2-(3-phenyl-propylamino)-benzoic acid) on proliferation, cell cycle and apoptosis of human trabecular meshwork cells. Method Using MTT, flow cytometry, Annexin V-PI and mitochondrial membrane potential, we explored the role of NPPB with different centration (10μM, 50μM, 100μM) in cell proliferation, cell cycle, apoptosis and mitochondrial membrane potential of TMC respectively. Rsults NPPB inhibited proliferation of TMC in a concentration-dependent manner. The proliferation of TMC was inhibited 55.6% by 100μM NPPB, and there was significant difference, P<; 0.01. Cell population increased in G₀/G₁ phase, while decreased in S phase induced by NPPB. NPPB was able to increase the apoptosis induced by 5-FU and reduce the mitochondrial membrane potential in TMC at the time point of 24h and 48h. Conclusion Chloride channel positively correlated with proliferation of TMC and promoted TMC into S phase via G1/S check point. In addition, ClC might be involved in anti-apoptosis mechanism through interfering internal mitochondrial pathway.