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bioRxiv · 10.1101/2023.08.08.552539

Cardiac function and ECM morphology are altered with high fat diets in Drosophila

Andrews, R. M.·Naik, S.·Pelletier, K.·Jacobs, J. R.
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Abstract

Cardiovascular disease is characterized by aberrant and excessive extracellular matrix (ECM) remodelling, termed fibrosis. Fibrotic remodelling is typically triggered by inflammation, which occurs systemically in obesity. Despite the contribution of fibrosis to adverse clinical outcomes and disease progression, there are no available treatments for this condition. Developing therapeutics for chronic conditions requires an understanding of in vivo ECM regulation, and how the ECM responds to a systemic challenge. We have therefore developed a Drosophila model for obesity via chronic high fat diet feeding and evaluated the response of the cardiac ECM to this metabolic challenge. We found that this model displays a striking disorganization of the cardiac ECM, with corresponding deficits in heart function. Our study shows that different genotypes tolerate varying levels of high fat diets, and that some genotypes may require a different percentage of fat supplementation for achieving an optimal obesity phenotype.

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Andrews, R. M., Naik, S., Pelletier, K., Jacobs, J. R.. 2023-08-09. Cardiac function and ECM morphology are altered with high fat diets in Drosophila. https://doi.org/10.1101/2023.08.08.552539

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