Differences in lipolysis between human subcutaneous and omental adipose tissues.
Level 5 - mechanism / opinion, no new human data
Narrative review synthesizing mechanistic and physiological studies without systematic methodology.
PubMed 8519504 · doi:10.3109/07853899709002451
What was done
This paper reviews in vivo and in vitro literature examining physiological and hormonal mechanisms underlying regional variations in lipolysis across human adipose depots, specifically comparing visceral (omental) fat to subcutaneous (abdominal and femoral/gluteal) fat in non-obese individuals and individuals with upper-body obesity.
What was found
No numerical values, sample sizes, or effect estimates are reported in the abstract. Qualitatively, basal and stimulated lipolysis is lowest in femoral/gluteal subcutaneous fat, intermediate in abdominal subcutaneous fat, and highest in visceral omental fat. Visceral adipocytes show higher activity of lipolytic beta-1, beta-2, and beta-3 adrenoceptors, whereas subcutaneous adipocytes demonstrate higher activity of antilipolytic alpha-2 adrenoceptors, adenosine receptors, and insulin receptors. In upper-body obesity, these differences are reported to be exacerbated by altered hormone-sensitive lipase function and receptor density changes.
Why it matters
Depot-specific regulation of lipolysis helps explain why visceral fat accumulation poses a greater risk for dyslipidemia and metabolic syndrome than peripheral subcutaneous fat accumulation.
Limits
The abstract represents a narrative review rather than a systematic synthesis or original clinical trial, providing no quantitative pooled data or methodology for study selection. Findings are based largely on mechanistic receptor assays, and the abstract text is truncated.
Cited by
- partial Unlike subcutaneous fat, visceral fat lipolysis does not shut down in response to insulin, continually releasing free fatty acids to the liver via the portal vein.