Adipose cell size: importance in health and disease

Abstract

Adipose tissue is necessary to harbor energy. To handle excess energy, adipose tissue expands by increasing adipocyte size (hypertrophy) and number (hyperplasia). Here, we have summarized the different experimental techniques used to study adipocyte cell size and describe adipocyte size in relation to insulin resistance, type 2 diabetes, and diet interventions. Hypertrophic adipocytes have an impaired cellular function, and inherent mechanisms restrict their expansion to protect against cell breakage and subsequent inflammation. Reduction of large fat cells by diet restriction, physical activity, or bariatric surgery therefore is necessary to improve cellular function and health. Small fat cells may also be dysfunctional and unable to expand. The distribution and function of the entire cell size range of fat cells, from small to very large fat cells, are an important but understudied aspect of adipose tissue biology. To prevent dysmetabolism, therapeutic strategies to expand small fat cells, recruit new fat cells, and reduce large fat cells are needed.

Insulin action is severely impaired in adipocytes of apparently healthy overweight and obese subjects

“…It is well established that increased adipocyte size is associated with insulin resistance . Nevertheless, this factor does not explain our findings.…”

Body fat mass and distribution as predictors of metabolic outcome and weight loss after Roux-en-Y gastric bypass

“…An alternative or additional explanation may be that intrinsic adipocyte factors are of importance for the development of insulin resistance. Large adipocytes are reported to have higher lipolysis rate 84,92 , and more proinflammatory adipokines such as MCP-1 and IL-6 are released from larger adipocytes 166 . These factors contribute to insulin resistance.…”

Neutrophil‐to‐lymphocyte ratio and its relation with pro‐inflammatory mediators, visceral adiposity and carotid intima‐media thickness in population with obesity

“…Atherosclerosis represents a cardiovascular risk, with multi‐aetiological factors like age, dyslipidemia, obesity, hypertension, type 2 Diabetes Mellitus (t2DM) and smoking . Likewise, systemic pro‐inflammatory mediators, the amount of visceral adipose tissue (VAT), the size of its adipocytes, the activation of resident macrophages and the adipokines produced may influence the inflammatory response and potentially regulate the atherogenic process …”

“…1,2 Likewise, systemic pro-inflammatory mediators, the amount of visceral adipose tissue (VAT), the size of its adipocytes, the activation of resident macrophages and the adipokines produced may influence the inflammatory response and potentially regulate the atherogenic process. 3,4 Moreover, early leucocyte recruitment is known to be closely associated with vascular endothelial dysfunction. [5][6][7] Immune cells are involved from earliest fatty streaks to late-stage complex vascular plaques, 5,8 where neutrophils play a role in the progression of atherogenesis and atherosclerosis.…”