Cells in the body take up nutrients from their environment and metabolize them in a complex set of biochemical reactions to generate energy and replicate. Control of these processes is particularly important for heart cells, which need large amounts of energy to drive blood flow throughout the body. Not surprisingly, the nutritional requirements of heart cells are very different than those of stem cells. This proposal will investigate the metabolism of pluripotent stem cells and how this changes during differentiation to cardiac cells. We will determine which nutrients are important to make functional heart cells and use this information to optimize growth conditions for producing heart cells for regenerative medicine and basic biology applications. We accomplish this by feeding cells nutrients (sugar, fat) labeled with isotopes. As these labeled molecules are consumed, the isotopes are incorporated into different metabolites which we track using mass spectrometry. This advanced technique will allow us to see how sugars and fat are metabolized inside stem cells and cardiac cells obtained through differentiation. We will also study the electrical activity of these heart cells to ensure that adequate nutrients are provided for the generation of cells with optimal function. Ultimately, this project will lead to new methods for producing functional heart cells for regenerative medicine and may also lead to insights into how cardiac cells malfunction in heart disease.
Heart disease is one of the leading causes of death in California. As a result, much of the regenerative medicine community in the state and the many Californians suffering from heart failure are interested in obtaining functional heart cells from stem cells. Our work will identify the most important nutrients required to coax stem cell-derived heart cells to behave like true adult heart cells. This information will make more effective cell models for researchers and companies to study how this disease affects heart cell metabolism. Since enzymes are highly targetable with drugs, the basic scientific findings from our work will be of great interest to California biotechnology companies and can stimulate job growth in the state. Our findings will also provide insight into very specific types of genetic heart disease, and this work may lead to additional grants from federal funding sources, bringing about additional revenue and job growth in California. A better understanding of how different nutrients influence heart cell function may provide guidance into new treatment strategies for heart disease. Finally, this work will highlight the importance of diet, nutrition, and healthy heart function, providing useful information relating to public health.
This Fundamental Mechanisms proposal will test the hypothesis that one can drive both the maturation and specification of human pluripotent stem cell (hPSC)-derived cardiomyocytes through metabolic manipulations. The investigators plan to characterize both metabolism and signaling pathways utilized during differentiation of cardiomyocyte sub-lineages (pacemaker, atrial and ventricular) from hPSC. Next they will identify nutrients critical for specification of these cardiomyocytes. Finally, the group plans to use this information to modulate nutrient conditions in order to stimulate cardiomyocyte maturation and enable sub-lineage specification.
Significance and Innovation
- This proposal makes serious efforts toward resolving a bottleneck in the field, the ability to generate mature cardiomyocytes from stem cells.
- If successful, this research could enable development of better in vitro cardiomyocyte disease and drug screening models .
- The suggested metabolic intervention is an innovative approach to cardiomyocyte differentiation. However, metabolic approaches are unlikely to substitute completely for other differentiation methods.
-The proposal employs innovative tools.
Feasibility and Experimental Design
- Preliminary data support proof of principle for the differentiation approach and the applicant’s ability to perform the proposed studies.
- The application proposes clear deliverables.
- The sophisticated functional metabolic assessment is a strength of the proposal. However, these assessments are likely to be performed using pooled populations of cells. Reviewers suggested this data would be enhanced by the addition of single cell based methods to assess specific cardiac myocyte subpopulations.
- Reviewers would have appreciated preliminary data supporting the applicant’s hypothesis for maturation.
- The PI has access to all necessary facilities and equipment.
Principal Investigator (PI) and Research Team
- The PI is a very accomplished investigator who is well-prepared to lead the proposed studies based on prior experience in stem cell differentiation and metabolomics.
- There are strong collaborators. The co-investigator is a leader in cardiomyocyte biology.
Responsiveness to the RFA
-The proposal very responsive to the RFA. It requires hPSC-derived cells and addresses a mechanistic question.
- Brian Harfe
- Sean Palecek