FNDC5 and Obesity: Indeed, prior assessments of psoriasis patients showed no statistically significant correlations of serum irisin levels with glucose level [26,28,30], uric acid [30], insulin [28,30], homeostasis model assessment of insulin resistance (HOMA-IR) [27,28,30], lipid parameters [26,27,30], BMI [26,30] and metabolic syndrome and obesity [29], whereas Bulur et al. observed a significant negative correlation between serum irisin concentration and levels of serum triglycerides and LDL cholesterol and a positive correlation with serum HDL cholesterol [28].