Myeloid Cell PKM2 Deletion Enhances Efferocytosis and Reduces Atherosclerosis. Issue 9 (11th April 2022)

• Record Type: Journal Article
• Authors: Doddapattar, Prakash; Dev, Rishabh; Ghatge, Madankumar; Patel, Rakesh B.; Jain, Manish; Dhanesha, Nirav; Lentz, Steven R.; Chauhan, Anil K.
• Is Part Of: Circulation research. Volume 130:Issue 9(2022)
• Page Start: 1289
• Page End: 1305
• Publication Date: 2022-04-11
• Subjects: atherosclerosis -- gene expression -- inflammation -- macrophages -- pyruvate kinase; Cardiovascular system -- Periodicals; Blood -- Circulation -- Periodicals; Blood Circulation; Cardiovascular System; Vascular Diseases; Sang -- Circulation -- Périodiques; Appareil cardiovasculaire -- Périodiques; 612.1
• DOI: 10.1161/CIRCRESAHA.121.320704
• Languages: English
• ISSNs: 0009-7330

Abstract

Abstract : Background: The glycolytic enzyme PKM2 (pyruvate kinase muscle 2) is upregulated in monocytes/macrophages of patients with atherosclerotic coronary artery disease. However, the role of cell type-specific PKM2 in the setting of atherosclerosis remains to be defined. We determined whether myeloid cell-specific PKM2 regulates efferocytosis and atherosclerosis. Methods: We generated myeloid cell-specific PKM2 −/− mice on Ldlr (low-density lipoprotein receptor)-deficient background (PKM2 mye-KO Ldlr −/− ). Controls were littermate PKM2 WT Ldlr −/− mice. Susceptibility to atherosclerosis was evaluated in whole aortae and cross sections of the aortic sinus in male and female mice fed a high-fat Western diet for 14 weeks, starting at 8 weeks. Results: PKM2 was upregulated in macrophages of Ldlr −/− mice fed a high-fat Western diet compared with chow diet. Myeloid cell-specific deletion of PKM2 led to a significant reduction in lesions in the whole aorta and aortic sinus despite high cholesterol and triglyceride levels. Furthermore, we found decreased macrophage content in the lesions of myeloid cell-specific PKM2 −/− mice associated with decreased MCP-1 (monocyte chemoattractant protein 1) levels in plasma, reduced transmigration of macrophages in response to MCP-1, and impaired glycolytic rate. Macrophages isolated from myeloid-specific PKM2 −/− mice fed the Western diet exhibited reduced expression of proinflammatory genes, including MCP-1, IL (interleukin)-1β, and IL-12. Myeloid cell-specific PKM2 −/− mice exhibited reduced apoptosis concomitant with enhanced macrophage efferocytosis and upregulation of LRP (LDLR-related protein)-1 in macrophages in vitro and atherosclerotic lesions in vivo. Silencing LRP-1 in PKM2-deficient macrophages restored inflammatory gene expression and reduced efferocytosis. As a therapeutic intervention, inhibiting PKM2 nuclear translocation using a small molecule reduced glycolytic rate, enhanced efferocytosis, and reduced atherosclerosis in Ldlr −/− mice. Conclusions: Genetic deletion of PKM2 in myeloid cells or limiting its nuclear translocation reduces atherosclerosis by suppressing inflammation and enhancing efferocytosis.