Calpain: a molecule to induce AIF-mediated necroptosis in RGC-5 following elevated hydrostatic pressure
1 Department of Anatomy and Neurobiology, Central South University School of Basic Medical Sciences, 172 Tongzi Po Road, 410013 Changsha, Hunan, China
2 Department of Biochemistry and Molecular Biology, Peking University Health Science Center, 100191 Beijing, China
3 Xiangya School of Medicine, Central South University, 410013 Changsha, Hunan, China
BMC Neuroscience 2014, 15:63 doi:10.1186/1471-2202-15-63Published: 12 May 2014
RIP3 (Receptor-interacting protein 3) pathway was mainly described as the molecular mechanism of necroptosis (programmed necrosis). But recently, non-RIP3 pathways were found to mediate necroptosis. We deliberate to investigate the effect of calpain, a molecule to induce necroptosis as reported (Cell Death Differ 19:245–256, 2012), in RGC-5 following elevated hydrostatic pressure.
First, we identified the existence of necroptosis of RGC-5 after insult by using necrostatin-1 (Nec-1, necroptosis inhibitor) detected by flow cytometry. Immunofluorescence staining and western blot were used to detect the expression of calpain. Western blot analysis was carried out to describe the truncated AIF (tAIF) expression with or without pretreatment of ALLN (calpain activity inhibitor). Following elevated hydrostatic pressure, necroptotic cells pretreated with or without ALLN was stained by Annexin V/PI, The activity of calpain was also examined to confirm the inhibition effect of ALLN. The results showed that after cell injury there was an upregulation of calpain expression. Upon adding ALLN, the calpain activity was inhibited, and tAIF production was reduced upon injury along with the decreased number of necroptosis cells.
Our study found that calpain may induce necroptosis via tAIF-modulation in RGC-5 following elevated hydrostatic pressure.