Related Experiment Videos
Ethanol-induced growth inhibition: the role of cyclic AMP-dependent protein kinase
1Department of Biochemistry, ECU School of Medicine, Greenville, North Carolina 27858.
Insights
Ethanol exposure in utero causes growth retardation by altering cellular signaling. This study found ethanol disrupts prostaglandin E2 and cyclic AMP pathways, impacting brain development in embryonic chicks.
Area of Science:
- Neuroscience
- Developmental Biology
- Pharmacology
Background:
- Prenatal ethanol exposure is a leading cause of infant growth deficits.
- Molecular mechanisms underlying ethanol's impact on development are under investigation.
- The adenylate cyclase-protein kinase cascade is a potential pathway affected by ethanol.
Purpose of the Study:
- To investigate the effects of ethanol on the adenylate cyclase-protein kinase cascade during early development.
- To explore the relationship between ethanol exposure, prostaglandin E2, cyclic AMP, and brain growth.
- To elucidate the molecular mechanisms of ethanol-induced growth inhibition.
Main Methods:
- Utilizing an embryonic chick model for controlled in vivo ethanol exposure.
- Measuring cellular prostaglandin E2 and cyclic AMP levels.
- Assaying in vitro adenylate cyclase and protein kinase activities.
- Assessing brain adenylate cyclase responsiveness to prostaglandin E2.
- Quantifying brain cytoplasmic cyclic AMP binding protein levels.
Main Results:
- Ethanol exposure increased cellular prostaglandin E2 and cyclic AMP levels, inversely correlated with brain weight.
- Basal adenylate cyclase and protein kinase activities remained unchanged in vitro.
- Ethanol suppressed the responsiveness of brain adenylate cyclase to exogenous prostaglandin E2.
- Cytoplasmic cyclic AMP binding protein levels were significantly reduced by ethanol treatment.
Conclusions:
- Ethanol exposure during embryonic development disrupts prostaglandin E2 and cyclic AMP signaling pathways.
- The observed alterations in signaling molecules correlate with reduced brain weight, suggesting a mechanism for growth retardation.
- Ethanol's impact on cyclic AMP binding protein may contribute to developmental deficits.
Abstract:
Growth retardation is the single most common deficit observed in infants exposed to ethanol in utero, and the molecular mechanisms responsible for this growth inhibition are a focus of ongoing research. Several lines of research have suggested that ethanol-induced changes in the adenylate cyclase-protein kinase cascade may be involved in this process. Using an embryonic chick model, it was demonstrated that ethanol exposure during early development caused increases in cellular prostaglandin E2 and cyclic AMP levels that were inversely correlated with brain weight. Paradoxically, basal adenylate cyclase and protein kinase catalytic activities, assayed in vitro, were not altered by ethanol dosing. Ethanol exposure did suppress the responsiveness of brain adenylate cyclase to exogenous PGE2. Furthermore, ethanol treatment significantly lowered the brain cytoplasmic levels of cyclic AMP binding protein.