MELATONIN TREATMENT PREVENTS THE PROGRESSION OF EXPERIMENTAL AUTOIMMUNE ORCHITIS IN RATS

MÉNDEZ CS; GONZÁLEZ LN; GUALDONI GS; IMSEN M; AMARILLA MS; SOBARZO CM; LUSTIG L; JACOBO P; THEAS MS

Congreso; LXIII Reunión Anual de la Sociedad Argentina de Investigación Clínica; 2018

Testicular inflammation is frequently associated to infertility. Wedeveloped an experimental model of autoimmune orchitis (EAO) inrats. In EAO interstitial lymphomonocytes increased from focal (50-60days, d) to severe EAO (70-80d), concomitantly with apoptosisof post-meiotic germ cells (GC) and pre-meiotic GC cycle arrest,leading to aspermatogenesis. Melatonin (MLT) is a hormone withanti-oxidant, anti-inflammatory and anti-apoptotic functions. The aimof this study was to evaluate whether MLT prevents the progressionof testicular damage and inflammation of rats with focal EAO. AdultWistar rats were immunized with testicular homogenate and adjuvantsor not treated (Normal group, N). 60d after the first immunization,EAO rats were semicastrated and treated daily with MLT (10mg/kg i.p, MLT group) or vehicle (1% methanol in saline, S Group) for20d. Testicular histopathological analysis was performed to determinethe inflammation and orchitis score (EAO=V+T, where V is afactor from 0 to 9 depending on the % of sloughed seminiferous tubules(ST) and T a factor that considers the severity of ST damage).The incidence of orchitis at 60d in the S group was 100% (7/7) andin the MLT group 89% (8/9). N group did not develop orchitis (EAOscore:0.0). EAO and inflammation score was only determined in ratsthat developed EAO at 60d. EAO score significantly increased in the 100% (7/7) of the S group rats (mean±ESM 60d:3.071±0.820,80d: 5.786±1.367, p