CHRONIC EXPOSURE TO URBAN AIR POLLUTION IN BUENOS AIRES CITY INDUCES OXIDATIVE STRESS, INFLAMMATION AND OLFACTORY ALTERATION OVER TIME IN MICE OLFACTORY BULB

FREIRE AGUSTINA; MARIANA GARCES; REYNOSO SOFIA; OCTAVIO DIANA; MARCHINI TIMOTEO; NAHUEL MENDEZ; MARTINEFSKI, MANUELA; TRIPODI, VALERIA; GOLDSTEIN JORGE; BUCHHOLZ BRUNO; ALVAREZ, SILVIA; MAGNANI NATALIA; EVELSON PABLO

Congreso; Redox Biology in translation annual meeting of the society for free radical research-Europe; 2023

Previous reports indicate that the brain is a target of air pollution, causing tissuedamage and functional alterations. The aim of this work was to study the chroniceffects of urban air pollution on olfactory bulb (OB), focusing on oxidative stressand inflammation as possible mechanisms mediating these effects. BALB/c 8-week-old mice were exposed to filtered air (FA, control) or urban air (UA) insidewhole-body chambers, located in a highly polluted area of Bs. As. city, for up to4w. Regarding OB redox status, UA exposed mice showed a decreased reducedglutathione level (p0.05), while glutathione reductase activity, and glutathioneperoxidase expression, were increased 4 w after exposure. Total superoxidedismutase (SOD) activity was found decrease after 1 w followed by an increaseafter 4 weeks of exposure, due to changes in SOD1 activity (p0.05). In addition,Heme oxygenase-1 expression was augmented in UA exposed group after 4 w(p0.05). NADPH oxidases (NOX) expression, particularly NOX4 and NOX2isoforms, which are predominant in the CNS, were augmented in UA exposedgroup at all the time points evaluated (p0.05). The loss of redox homeostasis ledto oxidative damage in the OB indicated by increases in 4-hydroxynonenal andnitrotyrosine levels after 4 w of exposure (p0.05). The evaluation of the inflammatory response showed an increase in iNOS and GFAP expression levels,TNFa and Ilb mRNA levels after 4w (p0.05). In order to determine if these alterations observed produce changes in tissue functionality, we performed abehavioral tests to evaluate olfactory discrimination and memory, we found thatUA mice had an alteration in the normal habituation/dishabituation pattern andin the medium-term memory. Taken together, these findings suggest that UAinhalation produce alterations in redox metabolism a neuroinflammation, thisresponse might be responsible of the neurotoxicity associated to environmentalPM.