Ethnic Differences in Adipose Tissue Dysfunction in the Development of Insulin Resistance and Type 2 Diabetes

Overview

This pilot study investigates the relationship between type 2 diabetes (T2D) and adipose tissue dysfunction across different ethnic groups. Adipose tissue dysfunction is characterised by abnormal fat distribution, including increased visceral, hepatic, and pancreatic fat, elevated inflammatory biomarkers, and impaired metabolic function. T2D is a chronic metabolic disease characterised by insulin resistance and disrupted glucose regulation. In the UK, its prevalence is significantly higher among South Asian and Black African/Caribbean populations than among White Europeans. Differences in adipose tissue distribution, particularly increased visceral fat accumulation, are thought to contribute to this disparity. Adipose tissue dysfunction, including chronic inflammation and altered adipokine secretion, is also associated with the development and progression of T2D. Previous studies have identified ethnic differences in body fat distribution and metabolic risk. Genetic factors influencing adipose tissue function may partly explain variations in fat storage and susceptibility to T2D across populations. However, the specific contribution of adipose tissue dysfunction to ethnic differences in T2D risk remains unclear. Evidence suggests that South Asians tend to have higher levels of liver and ectopic fat and a reduced capacity for safe subcutaneous fat storage, leading to fat accumulation in metabolically harmful sites. These characteristics are associated with increased insulin resistance and T2D risk. In contrast, Black populations often exhibit lower levels of visceral fat but still experience a high prevalence of T2D, indicating that factors beyond fat quantity may contribute to disease risk. Despite extensive research on ethnic disparities in metabolic health, few studies have directly compared markers of adipose tissue dysfunction across South Asian, Black African/Caribbean, and White European populations within a single study. This study aims to address this gap and improve understanding of the mechanisms linking adipose tissue dysfunction, insulin resistance, and T2D. The findings may help inform more targeted prevention and treatment strategies for ethnically diverse populations in the UK.

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