Research pertaining to this grant has evolved toward determining the role of microglia in mediating ethanolapoptotic action on developing R-endorphin neurons involved in regulation ofthe hypothalamic pituitaryadrenal axis (HPA) functions. The work conducted by us during the past funding period of the MERIT awarddemonstrated that alcohol exposure during early life causes activation of microglial cells and releasescytokines and chemokines that impact the physiological functions of hypothalamic neurons. Furthermore,early life exposure of ethanol may program the microglial cell population to produce more inflammatorycytokines following a stress challenge in the adulthood. Also, B-endorphin neurons that regulate the HPAaxis are not only a target of inflammatory cytokines and chemokines but also a modulator of microglial cellfunctions. Given the lack of information how microglia and BEP interact to control stress responses and theavailability of methods of culturing pure B-endorphin neurons from rat neuronal stem cells, we propose totest the following hypotheses: i) alcohol exposures stimulate microglia to produce inflammatory cytokinesincluding TNF-a that activates the nuclear factor-KB (NFKB) pathway and NADPH oxidase to induceapoptotic signaling in developing B-endorphin neurons; ii) li-endorphin neurons influences the ethanol'sability to increase inflammatory cytokines production by altering opioid receptor functions in microglial cells;and iii) early-life alcohol exposures program the microglial cell population to produce more inflammatorycytokines following a stress challenge during the adulthood. We will employ various state-of-the arttechniques involving in vitro differentiated pure B-endorphin cells, primary cultures of microglial cells,neonatal model of alcohol feeding, microarray and proteomic approaches, western blot, realtime PCR,MeDIP assay, double immunocytochemistry, gene knocking-down. We will also use both in vitro and in vivoapproaches. We anticipate these studies will identify whther a bi-directional communication betweenmicroglia and B-endorphin within the hypothalamus may predict risk for stress abnormality in a model ofdevelopmental alcohol exposures.RELEVANCE (See instructions):The proposed series of studies should continue to generate valuable data for better understanding pfethanol's neurotoxic action on developing B-endorphin neurons. Additionally, the proposed research shouldidentify compounds acting on novel targets to inhibit the release of a wide range of proinflammatory factprsfrom overactivated microglia that might be critical for preventing of B-endorphin neuronal death.
|Effective start/end date||8/1/91 → 12/31/18|
- National Institutes of Health (NIH)