Molecular mechanisms responsible for microglia-derived protection of Sprague-Dawley rat brain cells during in vitro ischemia.
Microglia-derived protection of brain cells (microglia, astrocytes, and neurons) during in vitro ischemic stress (deprivation of glucose, oxygen, and serum) was determined. Trypan blue exclusion assay, immunoblocking assay, Western blot analysis, and ELISA assay were used to determine the molecular mechanisms responsible for the microglia-derived protection. Results demonstrated that supernatants from the ischemic microglia protected all three cell-types from ischemia-induced damage by releasing the transforming growth factor-beta1 (TGF-beta1) and glial cell line-derived neurotrophic factor (GDNF). The protection of microglia was TGF-beta1 related, whereas astrocytes protection was GDNF-dependent. The protection of neurons was TGF-beta1 and GDNF independent, and the molecular nature responsible for their protection remains to be determined. These results indicate contribution from the surrounding cells and the types of receptors expressed on different brain cells probably also play an important role in determining their fate against ischemia.
Lu
Yen-Zhen
YZ
Department of Life Sciences, National Chung Hsing University, Taichung 40227, Taiwan ROC.
Lin
Chi-Hsin
CH
Cheng
Fu-Chou
FC
Hsueh
Chi-Mei
CM
D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000378:metabolism; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism*; D002545:Brain Ischemia / Q000503:physiopathology*; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D051100:Glial Cell Line-Derived Neurotrophic Factor; D017628:Microglia / Q000378:metabolism*; D009414:Nerve Growth Factors / Q000378:metabolism / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D018696:Neuroprotective Agents / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D016212:Transforming Growth Factor beta / Q000378:metabolism / Q000494:pharmacology
C495041:Gdnf protein, rat; D051100:Glial Cell Line-Derived Neurotrophic Factor; D009414:Nerve Growth Factors; D018696:Neuroprotective Agents; D016212:Transforming Growth Factor beta