Title | Complement 3a receptor 1 on macrophages and Kupffer cells is not required for the pathogenesis of metabolic dysfunction-associated steatotic liver disease. |
Publication Type | Journal Article |
Year of Publication | 2025 |
Authors | Homan, EA, Gilani, A, Rubio-Navarro, A, Johnson, MA, Schaepkens, OM, Cortada, E, de Lima, RPereira, Stoll, L, Lo, JC |
Journal | Elife |
Volume | 13 |
Date Published | 2025 Jan 08 |
ISSN | 2050-084X |
Keywords | Animals, Disease Models, Animal, Fatty Liver, Humans, Kupffer Cells, Liver, Macrophages, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Receptors, Complement, Receptors, G-Protein-Coupled |
Abstract | Together with obesity and type 2 diabetes, metabolic dysfunction-associated steatotic liver disease (MASLD) is a growing global epidemic. Activation of the complement system and infiltration of macrophages has been linked to progression of metabolic liver disease. The role of complement receptors in macrophage activation and recruitment in MASLD remains poorly understood. In human and mouse, C3AR1 in the liver is expressed primarily in Kupffer cells, but is downregulated in humans with MASLD compared to obese controls. To test the role of complement 3a receptor (C3aR1) on macrophages and liver resident macrophages in MASLD, we generated mice deficient in C3aR1 on all macrophages (C3aR1-MφKO) or specifically in liver Kupffer cells (C3aR1-KpKO) and subjected them to a model of metabolic steatotic liver disease. We show that macrophages account for the vast majority of C3ar1 expression in the liver. Overall, C3aR1-MφKO and C3aR1-KpKO mice have similar body weight gain without significant alterations in glucose homeostasis, hepatic steatosis and fibrosis, compared to controls on a MASLD-inducing diet. This study demonstrates that C3aR1 deletion in macrophages or Kupffer cells, the predominant liver cell type expressing C3ar1, has no significant effect on liver steatosis, inflammation or fibrosis in a dietary MASLD model. |
DOI | 10.7554/eLife.100708 |
Alternate Journal | Elife |
PubMed ID | 39773465 |
PubMed Central ID | PMC11709426 |
Grant List | DK132879 / NH / NIH HHS / United States 10.58275/aha.23divsup1074485.pc.gr.168377 / / American Heart Association / R01 DK121140 / DK / NIDDK NIH HHS / United States 908952 / / American Heart Association / R01 DK132879 / DK / NIDDK NIH HHS / United States 9-22-PDFPM-01 / / American Diabetes Association / DK121844 / NH / NIH HHS / United States R01 DK121844 / DK / NIDDK NIH HHS / United States T32 HL160520 / HL / NHLBI NIH HHS / United States 5T32HL160520 / NH / NIH HHS / United States DK121140 / NH / NIH HHS / United States |