Trypanosoma cruzi INFECTION AFFECTS ADIPOCYTE FUNCTION IN VIVO AND IN VITRO

GONZÁLEZ FLORENCIA, SILVINA VILLAR, JUDITH TONEATTO, FLORENCIA PACINI, LUCIANO D´ATTILIO, OSCAR BOTTASSO, GRACIELA PIWIEN-PILIPUK AND ANA ROSA PÉREZ.

Buenos Aires

Congreso; Reunion Conjunta de Sociedades de Biociencia; 2017

Trypanosoma cruzi INFECTION AFFECTSADIPOCYTE FUNCTION IN VIVO AND IN VITRO GonzálezFlorencia1, Silvina Villar1, Judith Toneatto2,Florencia Pacini1, Luciano D´Attilio3, Oscar Bottasso1,Graciela Piwien-Pilipuk2 and Ana Rosa Pérez1. 1-   Lab.de Estudios en Enfermedad de Chagas ? IDICER CONICET UNR2-    Lab. de Arquitectura Nuclear ? IBYME-CONICET3-   Lab.de Estudios en Tuberculosis ? IDICER CONICET UNR Adipose tissue (AT)influences energy homeostasis and inflammation and also acts as Trypanosoma cruzi (Tc) reservoir. Werecently showed that C57BL/6 mice infected with Tc displayed an exacerbatedpro-inflammatory milieu associated with metabolic abnormalities like manifesthypoglycemia, hypoleptinemia and a markedly loss of AT mass, which may play arole in lethality. Probably, pro-inflammatoryfactors released during infection may be involved in lipolysis and also influenceadipocyte function. In order to characterize AT wasting, we evaluate invivo how Tc infection affects AT histology, features of inflammatory infiltrateand the expression of factors involved in inflammation, lipolysis andadipogenesis. Other series of studies were carried out in vitro using 3T3-L1 adipocytes exposed to plasmas derived fromhealthy (Co) and Tc-infected mice. Results: After 17 days post-infection (17 dpi),adipocyte number and size diminished [size(pixel2x105) media±SEM;Co=2.7±0.2; Tc=1.3±0.1, p<0,05], while plasma glycerol and triglycerideswere increased. Noticeably, blockadeof TNF-α action (using TNF-R1/R2 KO mice) does not prevent loss of body mass orlethality (Relative weight, 17dpi, Co=0,5±0,1; Tc=0,2±0,1 KO=0.6±0.2; KOTc=0.2±0.1). In the AT, Tc mice revealed an increasedproportion of T, CD11b+ and CD11c+ cells and a decreased percentageof Treg cells compared to uninfected ones (all, p<0,05). mRNA levels ofadiponectin and leptin decreased in the AT from Tc animals compared to the Co, whereasTNF-α was increased. On the other hand, in vitro studies using 3T3-L1 adipocytesshowed that Tc-derived plasmas caused a diminution in the expression of C/EBPβ(transcription factor that promotes adipocyte differentiation), adiposetriglyceride lipase, hormone-sensitive lipase and adiponectin compared to Co-derivedplasmas. The results suggested that immune response increases lipolysis rate asa result of a high metabolic demand accompanied by adipocyte dysfunction.   Keywords: Trypanosoma cruzi, adipose tissue, inflammation