Leptin in septic arthritis: decreased levels during infection and amelioration of disease activity upon its administration

Weight loss is typically found during severe infections, e.g. septic arthri tis. The aim of our study was to evaluate the role of leptin, regulator of food intake and energy expenditure, for the development of Staphylococcus a ureus-triggered arthritis. Leptin production was found to be decreased duri ng murine S. aureus-induced arthritis. Treatment with recombinant leptin ne ither restored the basal leptin levels nor affected the weight loss during the disease, but it significantly decreased the severity of septic arthriti s. Exogenous leptin did not affect the staphylococcal load as measured in b lood, joints and kidneys. Preceding the effects on joint manifestations, se rum levels of interleukin-6 decreased in leptin-treated mice. In conclusion , the treatment with recombinant leptin reduced both the severity of joint manifestations in S. aureus-induced arthritis and the inflammatory response , as measured by serum IL-6 levels, without affecting the survival of bacte ria in vivo.