Assays included the measurement of Trp , kynurenine ( Kyn ) , and their ratio , neopterin , phenylalanine ( Phe ) , Tyr , as biologic markers ; leptin , plasma insulin , glucose , and homeostatic model assessment-insulin resistance ; and interleukin 6 , tumor necrosis factor alpha , and C-reactive protein , as biochemical and inflammatory markers at baseline and after 2 weeks of treatment .