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Age-independent Cardiac Protection by Pharmacological Activation of Beclin-1 During Endotoxemia and Its Association with Energy Metabolic Reprograming in Myocardium — A Targeted Metabolomics Study

ABSTRACT: Background: We previously showed that Beclin-1-dependent autophagy is cardiac protective in a rodent model of endotoxemia using young adult mice. In this report, we compared the potential therapeutic effects of pharmacological Beclin-1 activating peptide, TB-peptide, on the cardiac outcomes of young adult and aged mice during endotoxemia. We further examined alterations in myocardial metabolism induced by lipopolysaccharide (LPS) challenge with and without the TB-peptide treatment. Methods and Results: C57BL/6J mice of 10-week and 24-month-old were challenged by LPS at doses at which cardiac dysfunction occurred. Following the treatment of TB-peptide or control vehicle, heart contractility, circulating cytokines, and myocardial autophagy were evaluated. A targeted metabolomics assay was applied to analyze cardiac metabolism. TB-peptide boosted autophagic response, attenuated cytokine production, and improved cardiac performance in both young and aged mice during endotoxemia. A targeted metabolomics assay was designed to detect a pool of 361 known metabolites, of which 156 were detected in at least one of the heart tissue samples. LPS-induced impairments were found in glucose and amino acid (AA) metabolisms in mice of all ages, and TB-peptide provided ameliorative effects to rescue these alterations. However, lipid metabolites were upregulated in the young group but moderately downregulated in the aged by LPS, suggesting an age-dependent response. TB-peptide mitigated LPS-mediated trend of lipids in the young mice but provided little effect on the aged ones. Conclusion: Pharmacological activation of Beclin-1 by TB-peptide protects the heart in both young and aged population during endotoxemia, suggest a therapeutic potential for sepsis-induced cardiomyopathy. Metabolomics analysis suggests that this age-independent protection by TB-peptide is associated with reprograming of energy production via glucose and AA metabolisms.

ORGANISM(S): Mouse Mus Musculus

TISSUE(S): Heart

DISEASE(S): Endotoxemia

SUBMITTER: Qun Zang

PROVIDER: ST002178 | MetabolomicsWorkbench | Mon May 23 00:00:00 BST 2022

REPOSITORIES: MetabolomicsWorkbench

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Age-independent Cardiac Protection by Pharmacological Activation of Beclin-1 During Endotoxemia and Its Association with Energy Metabolic Reprograming in Myocardium — A Targeted Metabolomics Study

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