Impaired phagocytosis of apoptotic cells causes accumulation of bone marrow-derived macrophages in aged mice

• Published in: BMB reports Vol. 50; no. 1; pp. 43 - 48
• Main Authors: Kim, Ok-Hee, Kim, Hyojung, Kang, Jinku, Yang, Dongki, Kang, Yu-Hoi, Lee, Dae Ho, Cheon, Gi Jeong, Park, Sang Chul, Oh, Byung-Chul
• Format: Journal Article
• Language: English
• Published: Korea (South) Korean Society for Biochemistry and Molecular Biology 01.01.2017; 생화학분자생물학회
• Subjects: Aging - metabolism; Aging - pathology; Animals; Anti-Inflammatory Agents - pharmacology; Apoptosis - physiology; Bone Marrow Cells - cytology; Bone Marrow Cells - metabolism; Cell Differentiation - physiology; Cytokines - metabolism; Humans; Inflammation - pathology; Interleukin-10 - metabolism; Jurkat Cells; Lipopolysaccharide Receptors - metabolism; Macrophages - cytology; Macrophages - metabolism; Male; Mice; Mice, Inbred C57BL; Phagocytosis - physiology; 화학
• ISSN: 1976-6696; 1976-670X
• DOI: 10.5483/BMBRep.2017.50.1.167

Accumulation of tissue macrophages is a significant characteristic of disease-associated chronic inflammation, and facilitates the progression of disease pathology. However, the functional roles of these bone marrow-derived macrophages (BMDMs) in aging are unclear. Here, we identified agedependent macrophage accumulation in the bone marrow, showing that aging significantly increases the number of M1 macrophages and impairs polarization of BMDMs. We found that age-related dysregulation of BMDMs is associated with abnormal overexpression of the anti-inflammatory interleukin-10. BMDM dysregulation in aging impairs the expression levels of pro-inflammatory cytokines and genes involved in B-cell maturation and activation. Phagocytosis of apoptotic Jurkat cells by BMDMs was reduced because of low expression of phagocytic receptor CD14, indicating that increased apoptotic cells may result from defective phagocytosis of apoptotic cells in the BM of aged mice. Therefore, CD14 may represent a promising target for preventing BMDM dysregulation, and macrophage accumulation may provide diagnostic and therapeutic clues. [BMB Reports 2017; 50(1): 43-48].