LEP and obesity due to melanocortin 4 receptor deficiency: 14 Vuolteenaho Vuolteenaho K K Koskinen Koskinen A A Moilanen Moilanen T T Moilanen Moilanen E. E. Leptin levels are increased and its negative regulators, SOCS-3 and sOb-R are decreased in obese patients with osteoarthritis: a link between obesity and osteoarthritis.