In Vivo Pravastatin Treatment Reverses Hypercholesterolemia Induced Mitochondria-Associated Membranes Contact Sites, Foam Cell Formation, and Phagocytosis in Macrophages

Author(s)

Assis, Leandro Henrique de Paula ; Dorighello, Gabriel de Gabriel ; Rentz, Thiago ; Souza, Jane Cristina de ; Vercesi, Anibal Eugenio ; de Oliveira, Helena Coutinho Franco

• Document type: Journal article
• Source: FRONTIERS IN MOLECULAR BIOSCIENCES; v. 9, p. 17-pg., 2022-03-15.

Abstract

Statins are successful drugs used to treat hypercholesterolemia, a primary cause of atherosclerosis. In this work, we investigated how hypercholesterolemia and pravastatin treatment impact macrophage and mitochondria functions, the key cell involved in atherogenesis. By comparing bone marrow-derived macrophages (BMDM) of wild-type (WT) and LDL receptor knockout (LDLr-/-) mice, we observed hypercholesterolemia increased the number of contact sites at mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs), enhanced mitochondrial hydrogen peroxide release, altered the gene expression of inflammatory markers, and increased oxidized LDL (ox-LDL) uptake and phagocytic activity. Three months of in vivo pravastatin treatment of LDLr-/- mice reversed the number of contact sites at the MAM, ox-LDL uptake, and phagocytosis in LDLr-/- BMDM. Additionally, pravastatin increased BMDM mitochondrial network branching. In peritoneal macrophages (PMs), hypercholesterolemia did not change MAM stability, but stimulated hydrogen peroxide production and modulated gene expression of pro- and anti-inflammatory markers. It also increased mitochondrial branching degree and had no effects on ox-LDL uptake and phagocytosis in PM. Pravastatin treatment increased superoxide anion production and changed inflammation-related gene expression in LDLr-/- PM. In addition, pravastatin increased markedly the expression of the mitochondrial dynamics-related genes Mfn2 and Fis1 in both macrophages. In summary, our results show that hypercholesterolemia and pravastatin treatment affect macrophage mitochondria network structure as well as their interaction with the endoplasmic reticulum (ER). These effects impact on macrophage conversion rates to foam cell and macrophage phagocytic capacity. These findings associate MAM stability changes with known mechanisms involved in atherosclerosis progression and resolution. (AU)

• FAPESP's process: 17/03402-3 - Study of the association of mitochondrial and endoplasmic reticulum membranes in macrophages in the context of hypercholesterolemia: possible relevance for atherosclerosis
• Grantee: Leandro Henrique de Paula Assis
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 17/17728-8 - Mitochondrial function and dysfunction: implications for aging and associated diseases
• Grantee: Aníbal Eugênio Vercesi
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 17/02903-9 - Role of CETP expression in the macrophage redox state: possible consequences to inflammation and atherosclerosis
• Grantee: Gabriel de Gabriel Taffarello Dorighello
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/50615-1 - Cellular and molecular biology facility at the Biology Institute - UNICAMP
• Grantee: Helena Coutinho Franco de Oliveira
• Support Opportunities: Regular Research Grants