Estrogen has a Protective Role in Cardiac Function during Ischemia
This research focuses in understanding the role estrogen may have in reducing heart disease among females. We are interested in detecting differences in gene expression of apoptosis pathway genes, for estrogen deprived hearts subjected to various times of ischemia. We used a novel mouse model system, the Arko mouse, which does not synthesize estrogen, to study the effects of ischemia/ reperfusion on heart injury in the absence of estrogen. Research has demonstrated an increase in damage at the morphological level in hearts deprived of estrogen. We looked at how ischemia affects heart function at the level of the gene. The Arko hearts have suffered ischemia for five different times. The control Wild Type mouse only suffered a five minute period of ischemia. In this research the main interest is to determine if estrogen is cardio-protective before reperfusion (the restarting of blood flew to the heart) takes place during open heart surgery, during the time of ischemia. Also we are interested in knowing which specific apoptosis genes are differentially expressed over time in hearts deprived of estrogen and undergoing ischemia. We expect to answer the following questions: Does a short period of ischemia alone induce programmed cell death or "apoptosis"? What specific sub-set of genes involves in apoptosis are characteristic of ischemic insult to estrogen deprived cardiac tissue? Techniques such as: RNA Isolation, cDNA Labeling, Hybridization of cDNA and Gene Analysis are used to help us determine early apoptosis gene expression during ischemia alone. Some of our secondary questions were answered. Apoptosis responds in a significant way during the time of ischemia alone. We could observe an increased in apoptosis gene expression in ARKO mice versus the Wild Type mice which did not suffer as severe of a response, even though both of them were submitted to five minutes of ischemia alone. We could conclude that ischemia alone is sufficient to induce changes in genes expression related to pathway of apoptosis. Also that estrogen has a differential effect under the expression of genes during ischemia alone. For further analysis Dr. Bunick's lab will determine which differences in gene expression, due to estrogen, are beneficial in cardiac tissue.
School:
University of Puerto Rico at Bayamón
Department:
Molecular Biology
Research Advisor:
Dave Bunick
Department of Research Advisor:
Veterinary Bioscience
Year of Publication:
2003