title: Interleukin-6 prevents NMDA-induced neuronal death via Gp130 signaling-dependent IP3R inhibition.
abstract: OBJECTIVE
  To reveal the involvement of inositol 1,4,5-trisphosphate receptors (IP3R) and ryanodine receptors (RyR) in IL-6 prevention from neuronal apoptosis and necrosis induced by N-methyl-D-aspartate (NMDA).
  
  
  METHODS
  Cerebellar granule neurons (CGNs) from 8-day-old rats were exposed to IL-6 for 8 days and then stimulated with NMDA for 30 min. The 2-aminoethoxydiphenyl borate (2-APB) and dantrolene (DAN) were used to antagonize IP3R and RyR, respectively. Anti-gp130 monoclonal antibody (mAb) was employed to neutralize gp130, a 130-kDa signal-transducing β-subunit of IL-6 receptor complex. Neuronal apoptosis and necrosis were determined by TUNEL, fluorometric caspase-3 enzyme activity, annexin V-FITC/PI staining and ELISA. Western blot and real-time PCR measured IP3R1 and RyR2 expression, respectively.
  
  
  RESULTS
  IL-6 prevented the elevation of TUNEL-positive cells and caspase-3 expression and activity, and also suppressed the increase in annexin V-FITC/PI-positive cells and DNA- and histone-associated nucleosomes in cultured CGNs evoked by NMDA. These anti-apoptotic and anti-necrotic effects of IL-6 were larger on DAN-treated cells than on 2-APB-exposed neurons, since 2-APB treatment alone significantly inhibited the neuronal apoptosis and necrosis but DAN exposure alone did not alter the apoptosis and necrosis induced by NMDA. In support of these results, IL-6 downregulated IP3R1 but did not affect RyR2 expression. All these IL-6 effects were blocked by anti-gp130 mAb.
  
  
  CONCLUSIONS
  IL-6 prevention from NMDA-triggered Ca2+-induced Ca2+ release-mediated apoptosis and necrosis in CGNs depends on the inhibition of IP3R channel opening and expression rather than on RyR activity. IL-6 receptor-coupled gp130 signaling mediates this neuroprotection of IL-6 resistance to neuronal apoptosis and necrosis.
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu Province 210029, China. qinghuailiu@163.com.
authors.forename: Ao-Wang
authors.initials: AW
authors.lastname: Qiu
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu Province 210029, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu Province 210029, China.
authors.forename: Song-Tao
authors.initials: ST
authors.lastname: Yuan
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu Province 210029, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Xie
authors.affiliation: Department of Ophthalmology, The First Affiliated Hospital with Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu Province 210029, China. qinghuailiu@163.com.
authors.forename: Qing-Huai
authors.initials: QH
authors.lastname: Liu
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D001896:Boron Compounds / Q000494:pharmacology; D002478:Cells, Cultured; D002531:Cerebellum / Q000166:cytology*; D050822:Cytokine Receptor gp130 / Q000037:antagonists & inhibitors* / Q000276:immunology; D003620:Dantrolene / Q000494:pharmacology; D004347:Drug Interactions; D018690:Excitatory Amino Acid Agonists / Q000633:toxicity; D053496:Inositol 1,4,5-Trisphosphate Receptors / Q000037:antagonists & inhibitors* / Q000378:metabolism; D015850:Interleukin-6 / Q000494:pharmacology*; D009125:Muscle Relaxants, Central / Q000494:pharmacology; D016202:N-Methylaspartate / Q000633:toxicity; D009474:Neurons / Q000166:cytology* / Q000187:drug effects*; D018696:Neuroprotective Agents / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D000911:Antibodies, Monoclonal; D001896:Boron Compounds; D018690:Excitatory Amino Acid Agonists; D053496:Inositol 1,4,5-Trisphosphate Receptors; D015850:Interleukin-6; C488910:Itpr1 protein, rat; D009125:Muscle Relaxants, Central; D018696:Neuroprotective Agents; D050822:Cytokine Receptor gp130; D016202:N-Methylaspartate; C109986:2-aminoethoxydiphenyl borate; D003620:Dantrolene