title: Calpain: a molecule to induce AIF-mediated necroptosis in RGC-5 following elevated hydrostatic pressure.
abstract: BACKGROUND
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  Our study found that calpain may induce necroptosis via tAIF-modulation in RGC-5 following elevated hydrostatic pressure.
authors.forename: Lei
authors.initials: L
authors.lastname: Shang
authors.forename: Ju-Fang
authors.initials: JF
authors.lastname: Huang
authors.forename: Wei
authors.initials: W
authors.lastname: Ding
authors.forename: Shuang
authors.initials: S
authors.lastname: Chen
authors.forename: Li-Xiang
authors.initials: LX
authors.lastname: Xue
authors.forename: Ruo-Fei
authors.initials: RF
authors.lastname: Ma
authors.affiliation: Department of Anatomy and Neurobiology, Central South University School of Basic Medical Sciences, 172 Tongzi Po Road, 410013 Changsha, Hunan, China. xiongkun2001@163.com.
authors.forename: Kun
authors.initials: K
authors.lastname: Xiong
mesh_terms: D017209:Apoptosis; D051033:Apoptosis Inducing Factor / Q000378:metabolism*; D002154:Calpain / Q000378:metabolism*; D002460:Cell Line; D006801:Humans; D006874:Hydrostatic Pressure; D040542:Mechanotransduction, Cellular; D009336:Necrosis / Q000473:pathology / Q000503:physiopathology; D012165:Retinal Ganglion Cells / Q000378:metabolism* / Q000473:pathology*
chemical_list: D051033:Apoptosis Inducing Factor; C494830:AIFM1 protein, mouse; D002154:Calpain