Fat in flames: influence of cytokines and pattern recognition receptors on adipocyte lipolysis

Abstract

Adipose tissue has the largest capacity to store energy in the body and provides energy through the release of free fatty acids during times of energy need. Different types of immune cells are recruited to adipose tissue under various physiological conditions, indicating that these cells contribute to the regulation of adipose tissue. One major pathway influenced by a number of immune cells is the release of free fatty acids through lipolysis during both physiological (e.g., cold stress) and pathophysiological processes (e.g., obesity, type 2 diabetes). Adipose tissue expansion during obesity leads to immune cell infiltration and adipose tissue remodeling, a homeostatic process that promotes inflammation in adipose tissue. The release of proinflammatory cytokines stimulates lipolysis and causes insulin resistance, leading to adipose tissue dysfunction and systemic disruptions of metabolism. This review focuses on the interactions of cytokines and other inflammatory molecules that regulate adipose tissue lipolysis during physiological and pathophysiological states.

Linoleic acid and the pathogenesis of obesity

“…Additionally, TNF-α is capable of inducing adipocyte lipolysis in both rodents and humans [54], resulting in an increase in circulating free FA, which can lead to insulin resistance and T2DM development [55].This gives rise to the importance of both the reduction of absolute LA and the n-6:n-3 ratio in managing chronic inflammation.…”

Loss of Nlrp3 Does Not Protect Mice from Western Diet-Induced Adipose Tissue Inflammation and Glucose Intolerance

“…However, the molecular mechanisms by which obesity promotes AT inflammation remain poorly understood. Adipocyte hypertrophy in response to caloric excess leads to infiltration of immune cells such as macrophages and T lymphocytes into AT, which can cross-activate one another, hence perpetuating the secretion of inflammatory cytokines from AT [4, 6–8]. AT is viewed as an active immunological organ that controls whole-body metabolism and cardiovascular function through endocrine mechanisms [2–4].…”

Obesity shifts house dust mite-induced airway cellular infiltration from eosinophils to macrophages: effects of glucocorticoid treatment

“…Based on the 2007-2012 National Health and Nutrition Examination Survey (NHANES) more than two-thirds of Americans are overweight or obese [1]. Obesity is characterized by the addition of excess adipose tissue with enhanced immune cell infiltration, which is accompanied by increased production of pro-inflammatory mediators, altered glucose and lipid metabolism, and insulin resistance [2]. This dysfunctional metabolic state has been associated with an increased risk for asthma [3], a complex and heterogeneous condition defined by airway inflammation, remodeling, and hyperreactivity.…”