Alteration of Glycolysis/Pentose phosphate pathway in failing and recovering hearts

Background

Remarkable improvements in myocardial structure and function have been reported in some advanced heart failure (HF) patients undergoing "mechanical unloading" induced by left ventricular assist devices (LVAD). Unlike other HF therapies, which have also been associated with significant myocardial improvement, this tractable and specific LVAD population provides us access to pre-treatment myocardial tissue from both responders and non- responders which has enabled us to start probing the "signature" of myocardium that has the potential to improve. Our central hypothesis is that refining this "signature" will lead to a rational therapeutic approach in severe HF and will reveal broader recovery principles applicable to all stages and severity of HF. We hypothesized that specific metabolic adaptations drive myocardial recovery. Our preliminary data after examining myocardial tissue from normal donors and LVAD patients suggests a post- LVAD mismatch in glycolytic versus mitochondria oxidative phosphorylation that may indicate increased flux through the cardioprotective pentose phosphate pathway. We will employ novel and powerful in vivo metabolic flux studies using stable isotopes, mitochondrial respiratory measurements and metabolomics to test this hypothesis.

This project offers a rare opportunity to closely integrate clinical function, structure and in vivo mechanistic studies in human HF and recovery. Novel biological insights that inform both our clinical and basic science understanding of myocardial recovery has the potential to inform our understanding of HF pathology and potential recovery throughout the continuum of HF severity and will impact our treatment and management of advanced HF patients.

Student Role

The student will be required to take online courses for working with human subject and vaccinated before he/she can assist with myocardial tissue acquisition and 13C-glucose tracing experiments. The student will interact with the clinical personal, postdoctoral fellow and technical specialist in collecting and processing the human samples from the operating room.

The student will be responsible for RNA isolation and protein and metabolite extraction from myocardial tissue samples of control, and test groups for RNA, protein, and metabolomic analysis. The project activities will involve statistical analysis of the gene and protein expression that show significant difference among control, responders and non-responders at pre and post-LVAD unloading. The pathway analysis will include glycolysis and pentosephosphate flux comparison between responders and non-responders during the recovery induced by mechanical unloading. The key enzymes of glycolysis and pentose phosphate pathways (e.g. glucose-6-phosphate dehydrogenase and transketolase) will be evaluated.

Outcomes

A great advantage of working in Dr. Drakos' lab specifically is that student will gain exceptional experiences in different areas of biomedical research, both clinical and basic science. Student will have an opportunity to gain clinical experiences in the operating room and be able to observe the operations performed during the LVAD implantation and heart transplant/LVAD explant in the process of samples acquisition. The student will have plenty of hands-on involvement in conducting laboratory research and learn a great deal about metabolic pathways in understanding mechanisms of actual human disease. This research opportunity is well suited for student who would like to pursue a medical career and research in biomedical science (M.D./ Ph.D). The learning experience from this project will help and encourage the undergraduate student to prepare for research related career and professional development to become a scientist and physician devoted to evidence based medicine.

Stavros Drakos
Associate Professor

Internal Medicine
School of Medicine

Technical skills: The student will be assigned to work closely with a postdoctoral fellow who is responsible for the research project and will initially assist the postdoctoral fellow and technical specialist to perform the assays and experiments. The detail written protocols that are available in the laboratory will help guide the student to perform the assays required for experiments. The trainee are encouraged to operate on their own once they are proficient in performing the experiments. I will counsel the student occasionally to ensure that student understands the hypothesis being tested by experiments and the concluded outcome is correctly evaluated.

Communication skills: Undergraduate trainee is required to participate in a weekly laboratory meeting to learn and discuss the research in progress in my laboratory. The trainee will learn to assist and present the findings of project. I expect the student to develop the skill for presentation preparation, oral communication, and analytical process. The student will be required to present research publication related to the project, which he/she interested in a monthly journal club meeting. My expectation is that student will learn the skills for literature search, scientific critique and reasoning, and communication in preparation for the required final presentation at the Undergraduate Research Summer Symposium.

The undergraduate trainee will be given increasing personal responsibilities and independence in performing the experiments, analysis, and presentation once the student has demonstrated under supervision that he/she proficiently developed those capabilities.