JACC Basic Transl Sci. 2025 Aug 15. pii: S2452-302X(25)00286-4. [Epub ahead of print]10(9): 101334
Andrew A Gibb,
Kyle LaPenna,
Ryan B Gaspar,
Nadina R Latchman,
Yinfei Tan,
Carmen Choya-Foces,
Jake E Doiron,
Zhen Li,
Huijing Xia,
Michael P Lazaropoulos,
Mariell Conwell,
Thomas E Sharp,
Traci T Goodchild,
David J Lefer,
John W Elrod.
Heart failure with preserved ejection fraction (HFpEF) accounts for ∼50% of HF cases. The ZSF1-obese rat model recapitulates clinical features of HFpEF including hypertension, obesity, metabolic syndrome, exercise intolerance, and diastolic dysfunction. We utilized a systems-biology approach to define the metabolic and transcriptional signatures to gain mechanistic insight into pathways contributing to HFpEF development. Male ZSF1-obese, ZSF1-lean hypertensive controls, and WKY (wild-type) controls were compared at 14 weeks of age for extensive physiological phenotyping and left ventricle (LV) tissue harvesting for unbiased-metabolomics, RNA-sequencing, and mitochondrial morphology and function. Utilizing ZSF1-lean and WKY controls enabled a distinction between hypertension-driven molecular changes driving HFpEF pathology, versus hypertension + metabolic syndrome. Comparison of ZSF1-lean vs WKY (ie, hypertension-exclusive effects) revealed metabolic remodeling suggesting increased aerobic glycolysis, decreased β-oxidation, and dysregulated purine and pyrimidine metabolism with few transcriptional changes. ZSF1-obese rats displayed worsened metabolic remodeling and robust transcriptional remodeling highlighted by upregulation of inflammatory genes and downregulation of the mitochondrial structure/function and metabolic processes. Integrated network analysis of metabolomic and RNAseq datasets revealed downregulation of most catabolic energy producing pathways, manifesting in a marked decrease in the energetic state (ie, reduced ATP/ADP, PCr/ATP). Cardiomyocyte ultrastructure analysis revealed decreased mitochondrial area, size, and cristae density, as well as increased lipid droplet content in HFpEF hearts. Impaired mitochondrial function was demonstrated by decreased substrate-mediated respiration and dysregulated calcium handling. Collectively, the integrated omics approach applied here provides a framework to uncover novel genes, metabolites, and pathways underlying HFpEF, with an emphasis on mitochondrial energy metabolism as a potential interventional target.
Keywords: HFpEF; cardiac remodeling; heart failure; metabolism; mitochondria