As a member of the tumor necrosis factor-α-related protein family, complement-1q tumor necrosis factor-α-related protein isoform 5 (CTRP5) has been found to be associated with obesity and insulin resistance (IR).
Overweight/obese individuals (BMI ≥ 25 kg/m<sup>2</sup>) showed a lower serum CTRP5 level than lean subjects (BMI < 25 kg/m<sup>2</sup>) in the study population (124.1 (99.12-147.37) vs. 103.9 (79.15-124.25) <i>μ</i>g/L; <i>P</i> < 0.01).
In children adipocyte C1QTNF5 expression is already strongly related to the degree of obesity and is associated with obesity-related AT alterations, systemic CTRP5 serum levels as well as circulating markers of metabolic disease and is positively regulated by TNFα in vitro.