2013/07/09 by Antonio Giordano, Incoronata Murano, Eleonora Mondini +6 · 295 citations
Biochemistry, Genetics and Molecular Biology · Chemistry · Medicine · #Adipokines, Inflammation, and Metabolic Diseases #Anatomy #Apoptosis #Biochemistry #Biology #Cardiovascular Disease and Adiposity #Cell biology #Chemistry #Die (integrated circuit) #Inflammasome and immune disorders #Materials science #Nanotechnology #Programmed cell death #Pyroptosis #Ultrastructure
paper · pdf · doi:10.1194/jlr.m038638
published in Journal of Lipid Research 54(9), 2423-2436 (Elsevier BV)
openalex publication_date 2013/07/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We previously suggested that, in obese animals and humans, white adipose tissue inflammation results from the death of hypertrophic adipocytes; these are then cleared by macrophages, giving rise to distinctive structures we denominated crown-like structures. Here we present evidence that subcutaneous and visceral hypertrophic adipocytes of leptin-deficient (ob/ob and db/db) obese mice exhibit ultrastructural abnormalities (including calcium accumulation and cholesterol crystals), many of which are more common in hyperglycemic db/db versus normoglycemic ob/ob mice and in visceral versus subcutaneous depots. Degenerating adipocytes whose intracellular content disperses in the extracellular space were also noted in obese mice; in addition, increased anti-reactive oxygen species enzyme expression in obese fat pads, documented by RT-PCR and immunohistochemistry, suggests that ultrastructural changes are accompanied by oxidative stress. RT-PCR showed NLRP3 inflammasome activation in the fat pads of both leptin-deficient and high-fat diet obese mice, in which formation of active caspase-1 was documented by immunohistochemistry in the cytoplasm of several hypertrophic adipocytes. Notably, caspase-1 was not detected in FAT-ATTAC transgenic mice, where adipocytes die of apoptosis. Thus, white adipocyte overexpansion induces a stress state that ultimately leads to death. NLRP3-dependent caspase-1 activation in hypertrophic adipocytes likely induces obese adipocyte death by pyroptosis, a proinflammatory programmed cell death.