EFFECT OF TNFRp55 DEFICIENCY ON THE CIRCADIAN PROFILES OF IMMUNOENDOCRINE SIGNALS

RAGUSSA V; ARIAS JL; DE LA VEGA; CASAIS M; DI GENARO MS; RASTRILLA AM; ANZULOVICH A

Puerto Madryn

Congreso; 46th. Annual meeting SAIB; 2010

SAIB

The biological rhythms in the peripheral clocks are regulated byneuroimmunoendocrine signals proceeding, directly or indirectly,from the master clock in the suprachiasmatic nucleus. TNF is apleiotropic inflammatory cytokine and exhibits its biologicalproperties upon binding to its cognate membrane receptorsTNFRp55 and TNFRp75. Our objective was to assess the impact ofTNFRp55 deficiency on the circadian profiles of the rest-activitycycle, IL-17 and progesterone (Pg) levels in C57BL/6 wild typeand TNFRp55-/- mice. Circadian locomotor activity was registeredunder constant darkness during 20 days using the Archron system.IL-17 and Pg levels were determined by ELISA and RIA,respectively. We observed nocturnal activity decreased anddesynchronized in the TNRFp55-/- mice. IL-17 levels varythroughout a day in serum, joint, ovary and liver in the wild typestrain. Pg also showed a circadian profile in the same tissues exceptliver. Interestingly TNFRp55 deficiency phase shifted most ofthose temporal oscillations. These results suggest that TNF wouldplay a role in the circadian modulation of endogenous rhythmsthrough its p55 receptor.