Effects of Diazepam Treatment on Neuroinflammation at Hippoccampus in a Chronic Model of Experimental Autoimmune Encephalomyelitis

ZALOSNIK, MARÍA INÉS; ROTH, GERMAN; FABIO, MARIA CAROLINA; DEGANO, ALICIA

Córdoba

Congreso; XXXIII Congreso Anual de la Sociedad Argentina de Investigación en Neurociencias; 2018

Sociedad Argentina de Neurociencias

Experimentalautoimmune encephalomyelitis (EAE) is an inflammatory demyelinating diseasethat mimics many of the clinical and pathological features of multiplesclerosis. Recently, we found that 2 mg/kg of chronic diazepam (Dz) treatmentreversed motor signs of the disease and attenuates mRNA expression ofinflammatory cytokines at hippocampus. In the present study, we aimed toanalyze the mRNA expression of the highly conserved 18-kDa translocator protein(TSPO) at hippocampus as a biomarker of neuroinflammation and as the possiblereceptor that mediates the action of Dz in our experimental model. We also analyzedmicrogliosis and astrogliosis at hippocampus, as the upregulation of TSPO playsa role in the response of astrocytes and microglia during active brain disease.Female mice were immunized with MOG35-55 peptide or adjuvant alone and pertussis toxin.At first symptom, animals were injected with diazepam or saline alone every 48h. After recovery of clinical signs, brains were harvested forimmunofluorescence against Iba1 and GFAP or mRNA expression of TSPO through RT-PCR.We found that Dz ameliorated microgliosis and astrogliosis at hippocampus ofEAE animals. Interestingly, Dz downregulated TSPO expression in both EAE andcontrol animals. Further experiments are needed in order to dilucidate apossible mechanism that could explain diazepam effects on motor signs of thedisease and its anti-inflammatory effect at hippocampus