Diabetes and Obesity Center, Department of Medicine, University of Louisville, Louisville, Kentucky.
Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee.
Am J Physiol Heart Circ Physiol. 2021 Oct 1;321(4):H784-H797. doi: 10.1152/ajpheart.00411.2021. Epub 2021 Sep 17.
Coenzyme A (CoA) is an essential cofactor required for intermediary metabolism. Perturbations in homeostasis of CoA have been implicated in various pathologies; however, whether CoA homeostasis is changed and the extent to which CoA levels contribute to ventricular function and remodeling during pressure overload has not been explored. In this study, we sought to assess changes in CoA biosynthetic pathway during pressure overload and determine the impact of limiting CoA on cardiac function. We limited cardiac CoA levels by deleting the rate-limiting enzyme in CoA biosynthesis, pantothenate kinase 1 (). We found that constitutive, cardiomyocyte-specific deletion (cm) significantly reduced PANK1 mRNA, PANK1 protein, and CoA levels compared with sufficient littermates (cm) but exerted no obvious deleterious impact on the mice at baseline. We then subjected both groups of mice to pressure overload-induced heart failure. Interestingly, there was more ventricular dilation in cm during the pressure overload. To explore potential mechanisms contributing to this phenotype, we performed transcriptomic profiling, which suggested a role for in regulating fibrotic and metabolic processes during the pressure overload. Indeed, deletion exacerbated cardiac fibrosis following pressure overload. Because we were interested in the possibility of early metabolic impacts in response to pressure overload, we performed untargeted metabolomics, which indicated significant changes to metabolites involved in fatty acid and ketone metabolism, among other pathways. Collectively, our study underscores the role of elevated CoA levels in supporting fatty acid and ketone body oxidation, which may be more important than CoA-driven, enzyme-independent acetylation in the failing heart. Changes in CoA homeostasis have been implicated in a variety of metabolic diseases; however, the extent to which changes in CoA homeostasis impacts remodeling has not been explored. We show that limiting cardiac CoA levels via PANK deletion exacerbated ventricular remodeling during pressure overload. Our results suggest that metabolic alterations, rather than structural alterations, associated with Pank1 deletion may underlie the exacerbated cardiac phenotype during pressure overload.
辅酶 A (CoA) 是中间代谢所必需的辅助因子。CoA 稳态的失调与各种病理有关;然而,在压力超负荷期间,CoA 稳态是否发生变化以及 CoA 水平在多大程度上影响心室功能和重构尚未得到探索。在这项研究中,我们试图评估压力超负荷期间 CoA 生物合成途径的变化,并确定限制 CoA 对心脏功能的影响。我们通过删除 CoA 生物合成的限速酶泛酸激酶 1 (PANK1) 来限制心脏 CoA 水平。我们发现,与足够的同窝仔相比,组成型、心肌细胞特异性的 缺失 () 显著降低了 PANK1 mRNA、PANK1 蛋白和 CoA 水平,但在基线时对小鼠没有明显的有害影响。然后,我们将两组小鼠置于压力超负荷诱导的心力衰竭中。有趣的是,在压力超负荷期间,cm 中的心室扩张更多。为了探索导致这种表型的潜在机制,我们进行了转录组谱分析,该分析表明在压力超负荷期间 可能调节纤维化和代谢过程。事实上, 缺失在压力超负荷后加剧了心脏纤维化。因为我们对压力超负荷后早期代谢影响的可能性感兴趣,所以我们进行了非靶向代谢组学分析,这表明涉及脂肪酸和酮体代谢等途径的代谢物发生了显著变化。总的来说,我们的研究强调了升高的 CoA 水平在支持脂肪酸和酮体氧化中的作用,这在衰竭心脏中可能比 CoA 驱动的、酶非依赖性乙酰化更为重要。CoA 稳态的变化与多种代谢疾病有关;然而,CoA 稳态变化对重构的影响程度尚未得到探索。我们通过 PANK 缺失显示,限制心脏 CoA 水平在压力超负荷期间加剧了心室重构。我们的结果表明,与 Pank1 缺失相关的代谢改变,而不是结构改变,可能是压力超负荷期间心脏表型加剧的基础。