ANGPTL8 and obesity due to melanocortin 4 receptor deficiency: These studies show that betatrophin levels were altered in various physiologic conditions, such as the postprandial state [18], and pathological conditions, such as type 2 diabetes [18,23,38,50], type 1 diabetes [22], obesity [18,50], and were associated with metabolic parameters, such as BMI [18,50], glucose [18,38], insulin resistance [38,50], LDL-C [24], HDL-C and triglycerides [50].