INS and obesity due to melanocortin 4 receptor deficiency: This correlation is supported also by the finding that a monoclonal antibody that targets serum FABP4 lowered fasting blood glucose, increased insulin sensitivity, and reduced fat mass in mouse models (Burak et al. 2015).Thus, high levels of circulating FABP4 are not only to be considered a biomarker of obesity but also the manifestation of a FABP4 chaperonopathy contributing to the causation of the metabolic syndrome.