RBP4 and gestational diabetes: Another example is the study by Tsiotra et al., in which circulating levels of visfatin, omentin-1, chemerin, RBP4, resistin, adiponectin, leptin, TNF-α, and IL-6 were measured in 23 women with NGT and 15 with GDM, all with a resolution of pregnancy at term, and classified as obese (BMI ≥ 30 kg/m2) and non-obese (BMI < 30 kg/m2).