INS and polycystic ovary syndrome: The level of GDF-15 tends to decrease during the 3 h of saline and intralipid infusions after chronic exercise training; the decrease was significant in saline control group (P = 0.03); co-infusion of insulin reversed this decline in GDF-15 in the saline control group (P = 0.02) and intralipid PCOS women (P = 0.01) (Table 4).