PMID- 28622174 OWN - NLM STAT- MEDLINE DCOM- 20170814 LR - 20200930 IS - 1526-7598 (Electronic) IS - 0003-2999 (Print) IS - 0003-2999 (Linking) VI - 125 IP - 1 DP - 2017 Jul TI - Insufficient Astrocyte-Derived Brain-Derived Neurotrophic Factor Contributes to Propofol-Induced Neuron Death Through Akt/Glycogen Synthase Kinase 3beta/Mitochondrial Fission Pathway. PG - 241-254 LID - 10.1213/ANE.0000000000002137 [doi] AB - BACKGROUND: Growing animal evidence demonstrates that prolonged exposure to propofol during brain development induces widespread neuronal cell death, but there is little information on the role of astrocytes. Astrocytes can release neurotrophic growth factors such as brain-derived neurotrophic factor (BDNF), which can exert the protective effect on neurons in paracrine fashion. We hypothesize that during propofol anesthesia, BDNF released from developing astrocytes may not be sufficient to prevent propofol-induced neurotoxicity. METHODS: Hippocampal astrocytes and neurons isolated from neonatal Sprague Dawley rats were exposed to propofol at a clinically relevant dose of 30 muM or dimethyl sulfoxide as control for 6 hours. Propofol-induced cell death was determined by propidium iodide (PI) staining in astrocyte-alone cultures, neuron-alone cultures, or cocultures containing either low or high density of astrocytes (1:9 or 1:1 ratio of astrocytes to neurons ratio [ANR], respectively). The astrocyte-conditioned medium was collected 12 hours after propofol exposure and measured by protein array assay. BDNF concentration in astrocyte-conditioned medium was quantified using enzyme-linked immunosorbent assay. Neuron-alone cultures were treated with BDNF, tyrosine receptor kinase B inhibitor cyclotraxin-B, glycogen synthase kinase 3beta (GSK3beta) inhibitor CHIR99021, or mitochondrial fission inhibitor Mdivi-1 before propofol exposure. Western blot was performed for quantification of the level of protein kinase B and GSK3beta. Mitochondrial shape was visualized through translocase of the outer membrane 20 staining. RESULTS: Propofol increased cell death in neurons by 1.8-fold (% of PI-positive cells [PI%] = 18.6; 95% confidence interval [CI], 15.2-21.9, P < .05) but did not influence astrocyte viability. The neuronal death was attenuated by a high ANR (1:1 cocultures; fold change [FC] = 1.17, 95% CI, 0.96-1.38, P < .05), but not with a low ANR [1:9 cocultures; FC = 1.87, 95% CI, 1.48-2.26, P > .05]). Astrocytes secreted BDNF in a cell density-dependent way and propofol decreased BDNF secretion from astrocytes. Administration of BDNF, CHIR99021, or Mdivi-1 significantly attenuated the propofol-induced neuronal death and aberrant mitochondria in neuron-alone cultures (FC = 0.8, 95% CI, 0.62-0.98; FC = 1.22, 95% CI, 1.11-1.32; FC = 1.35, 95% CI, 1.16-1.54, respectively, P < .05) and the cocultures with a low ANR (1:9; FC = 0.85, 95% CI, 0.74-0.97; FC = 1.08, 95% CI, 0.84-1.32; FC = 1.25, 95% CI, 1.1-1.39, respectively, P < .05). Blocking BDNF receptor or protein kinase B activity abolished astrocyte-induced neuroprotection in the cocultures with a high ANR (1:1). CONCLUSIONS: Astrocytes attenuate propofol-induced neurotoxicity through BDNF-mediated cell survival pathway suggesting multiple neuroprotective strategies such as administration of BDNF, astrocyte-conditioned medium, decreasing mitochondrial fission, or inhibition of GSK3beta. FAU - Liu, Yanan AU - Liu Y AD - From the Departments of *Anesthesiology and daggerPhysiology, Medical College of Wisconsin, Milwaukee, Wisconsin. FAU - Yan, Yasheng AU - Yan Y FAU - Inagaki, Yasuyoshi AU - Inagaki Y FAU - Logan, Sarah AU - Logan S FAU - Bosnjak, Zeljko J AU - Bosnjak ZJ FAU - Bai, Xiaowen AU - Bai X LA - eng GR - P01 GM066730/GM/NIGMS NIH HHS/United States GR - R01 GM112696/GM/NIGMS NIH HHS/United States GR - R01 HL034708/HL/NHLBI NIH HHS/United States PT - Journal Article PL - United States TA - Anesth Analg JT - Anesthesia and analgesia JID - 1310650 RN - 0 (Anesthetics, Intravenous) RN - 0 (Brain-Derived Neurotrophic Factor) RN - 0 (Culture Media, Conditioned) RN - EC 2.7.10.1 (Ntrk2 protein, rat) RN - EC 2.7.10.1 (Protein-Tyrosine Kinases) RN - EC 2.7.10.1 (Receptor, trkB) RN - EC 2.7.11.1 (Glycogen Synthase Kinase 3 beta) RN - EC 2.7.11.1 (Gsk3b protein, rat) RN - EC 2.7.11.1 (Proto-Oncogene Proteins c-akt) RN - YI7VU623SF (Propofol) SB - IM CIN - Anesth Analg. 2017 Dec;125(6):2165-2166. PMID: 28953497 MH - Anesthetics, Intravenous/*toxicity MH - Animals MH - Animals, Newborn MH - Astrocytes/*drug effects/enzymology/pathology MH - Brain-Derived Neurotrophic Factor/*metabolism MH - Cell Death/drug effects MH - Cells, Cultured MH - Coculture Techniques MH - Culture Media, Conditioned/metabolism MH - Dose-Response Relationship, Drug MH - Glycogen Synthase Kinase 3 beta/*metabolism MH - Hippocampus/*drug effects/enzymology/pathology MH - Mitochondria/*drug effects/enzymology/pathology MH - Mitochondrial Dynamics/*drug effects MH - Neurons/*drug effects/enzymology/pathology MH - Paracrine Communication/*drug effects MH - Propofol/*toxicity MH - Protein-Tyrosine Kinases/metabolism MH - Proto-Oncogene Proteins c-akt/*metabolism MH - Rats, Sprague-Dawley MH - Receptor, trkB MH - Signal Transduction/drug effects PMC - PMC5484590 MID - NIHMS868180 EDAT- 2017/06/18 06:00 MHDA- 2017/08/15 06:00 PMCR- 2018/07/01 CRDT- 2017/06/17 06:00 PHST- 2017/06/18 06:00 [pubmed] PHST- 2017/08/15 06:00 [medline] PHST- 2017/06/17 06:00 [entrez] PHST- 2018/07/01 00:00 [pmc-release] AID - 10.1213/ANE.0000000000002137 [doi] PST - ppublish SO - Anesth Analg. 2017 Jul;125(1):241-254. doi: 10.1213/ANE.0000000000002137.