Dead adipocytes, detected as crown-like structures, are prevalent in visceral fat depots of genetically obese mice

• Published in: Journal of lipid research Vol. 49; no. 7; pp. 1562 - 1568
• Main Authors: Murano, I., Barbatelli, G., Parisani, V., Latini, C., Muzzonigro, G., Castellucci, M., Cinti, S.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.07.2008; Elsevier
• Subjects: adipocyte death; Adipocytes - cytology; Adipocytes - metabolism; Animals; Cell Death; Female; Intra-Abdominal Fat - cytology; Intra-Abdominal Fat - metabolism; macrophages; Mice; Mice, Obese; obesity; subcutaneous fat; macrophages; subcutaneous fat; obesity; adipocyte death
• ISSN: 0022-2275; 1539-7262
• DOI: 10.1194/jlr.M800019-JLR200

Accumulation of visceral fat is a key phenomenon in the onset of obesity-associated metabolic disorders. Macrophage infiltration induces chronic mild inflammation widely considered as a causative factor for insulin resistance and eventually diabetes. We previously showed that >90% of macrophages infiltrating the adipose tissue of obese animals and humans are arranged around dead adipocytes, forming characteristic crown-like structures (CLS). In this study we quantified CLS in visceral and subcutaneous depots from two strains of genetically obese mice, db/db and ob/ob. In both strains, CLS were prevalent in visceral compared with subcutaneous fat. Adipocyte size and CLS density exhibited a positive correlation both in visceral and in subcutaneous depots; however, the finding that adipocyte size was smallest and CLS density highest in visceral fat suggests a different susceptibility of visceral and subcutaneous adipocytes to death. Visceral fat CLS density was 3.4-fold greater in db/db than in ob/ob animals, which at the age at which our experimental strain was used are more prone to glucose metabolic disorders.