HOW OBESITY AFFECTS INSULIN RESISTANCE AND THE CONSEQUENCES OF THIS PROCESS.

• DOI: https://doi.org/10.22533/at.ed.1595212512053

• Palavras-chave: obesity, insulin resistance,

• Keywords: obesity, insulin resistance,

• Abstract:

  Introduction. Obesity is a medical condition characterized by the excessive accumulation of body fat, which has become a global concern due to its impact on public health. One of the main problems associated with obesity is insulin resistance, a condition in which the body's cells are less sensitive to the hormone insulin, which is essential for glucose metabolism. People with obesity and type 2 diabetes (T2D) often have lower postprandial insulin levels than individuals without T2DM, and the relative insufficiency of insulin contributes to the hyperglycemia characteristic of these patients. In addition, obesity is related to cardiovascular diseases, which represent significant public health risks, especially in today's Western societies. Objective. The aim of this study was to conduct a literature review to identify new data exploring the relationship between increased adipose tissue and insulin resistance, highlighting the metabolic processes involved in this mechanism. Material and Methods. This review analyzed published studies that address the relationship between obesity, insulin resistance and associated metabolic processes. The search was conducted in the main academic databases, such as PUBMED, SCIELO and LILACS, initially identifying 60 papers using the terms: Inflammation in obesity, Adipokines and resistance, Lipotoxicity and mitochondria, Microbiota and obesity, Hormones and appetite control, Diets and insulin resistance, Pharmacological therapies, Lifestyle and inflammation, Adipose tissue modulation, Oxidative stress. These terms were combined using Boolean operators: "and", "or" and "not". After analysis, 36 studies were selected for the review, based on relevance, methodological quality and timeliness. Discussion. The relationship between obesity and insulin resistance is multifactorial and involves various metabolic, inflammatory and hormonal mechanisms. The increase in adipose tissue, especially in the visceral region, alters the profile of adipokines and inflammatory mediators, such as TNF-α, IL-6 and leptin, which activate intracellular pathways such as NF-κB and JNK, leading to inhibitory phosphorylation of the IRS-1 receptor and insulin resistance (AHMED et al., 2021). In addition, the lipotoxicity caused by excess free fatty acids promotes oxidative stress and mitochondrial dysfunction, aggravating the metabolic condition (YOON et al., 2021). Adipose tissue, in addition to storing fat, functions as an endocrine organ, secreting adipokines that modulate insulin sensitivity and the inflammatory state, factors that favor the development of complications such as cardiovascular diseases (FONSECA- ALANIZ et al., 2006; PALAY & JOHNSON, 2018). Lifestyle interventions, balanced diets and pharmacological strategies have shown potential in reducing inflammation and improving insulin sensitivity, reinforcing the importance of integrated approaches in the treatment of obesity (TRACHTENBERG et al., 2021). However, a thorough understanding of metabolic mechanisms is still essential for the development of more effective therapies.