Abstract
Overweight and obesity are defined as abnormal or excessive fat accumulation in the body. White adipose tissue produces a variety of hormones and cytokines commonly referred to as adipokines.
Different spectrum and quantity of adipokines produced by adipose tissue of obese patients is involved in many obesity-related pathologies (type 2. diabetes mellitus, cardiovascular disease, inflammatory response). Recently, numerous clinical studies explored hypothesis that visceral adipose tissue of obese patients is a primary site where subclinical inflammation arises.
This hypothesis suggests that the storage capacity of adipocytes of obese individuals for triglycerides is constantly overloaded due to chronically positive energy balance leading to their necrosis. Adipocyte necrosis stimulates the infiltration of visceral adipose tissue by macrophages.
Adipose tissue of obese individuals contains excessive amounts of activated proinflammatory macrophages referred to as M1 subtype. These macrophages produce many pro-inflammatory factors along with low secretion of anti-inflammatory cytokines and adipokines.
Constant release of proinflammatory factors into circulation then causes subclinical systemic inflammatory response which is directly linked to metabolic complications of obesity. Identification of the mechanisms inducing inflammatory response and identification of the types of immune cells involved in this process could contribute to future treatment strategies of metabolic complications of obesity.