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Water is the principal source of human exposure to fluoride (F). The high permeability of the placenta and blood-brain barrier to F during the intrauterine life up to the end of lactation may be crucial to neurological fetus development. Therefore, this study explores the effects of 5 and 10 mg/l F exposure during entire gestation and lactation periods, through neurobehavioral and biochemical tests performed on 90-day-old male offspring rats. The present study shows that pre and peri-natal exposure to F doses that are in the range of those found in groundwater sources in Argentina affects long-term memory and leads to a depressive-like behavior in 90-day-old male pup. Furthermore, the purpose of the investigation was to find out the possible biochemical changes through which the pre and peri-natal F-administration could generate such behavioral variations. We found alterations in transaminases, acetylcholinesterase, and alkaline phosphatase enzymes activity in specific brain areas (the prefrontal cortex, the striatum, and the hippocampus), together with findings regarding misbalanced oxidative stress. In conclusion, F exposure during the early stages of rat development alters brain-oxidative stress markers as well as the activity of enzymes implicated in cholinergic and glutamatergic systems. These molecular changes could contribute to the neurobehavioral alterations described in the present investigation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

Pesticide exposure is associated with cognitive and psychomotor disorders. Glyphosate-based herbicides (GlyBH) are among the most used agrochemicals, and inhalation of GlyBH sprays may arise from frequent aerial pulverizations. Previously, we described that intranasal (IN) administration of GlyBH in mice decreases locomotor activity, increases anxiety, and impairs recognition memory. Then, the aim of the present study was to investigate the mechanisms involved in GlyBH neurotoxicity after IN administration. Adult male CF-1 mice were exposed to GlyBH IN administration (equivalent to 50 mg/kg/day of Gly acid, 3 days a week, during 4 weeks). Total thiol content and the activity of the enzymes catalase, acetylcholinesterase and transaminases were evaluated in different brain areas. In addition, markers of the cholinergic and the nigrostriatal pathways, as well as of astrocytes were evaluated by fluorescence microscopy in coronal brain sections. The brain areas chosen for analysis were those seen to be affected in our previous study. GlyBH IN administration impaired the redox balance of the brain and modified the activities of enzymes involved in cholinergic and glutamatergic pathways. Moreover, GlyBH treatment decreased the number of cholinergic neurons in the medial septum as well as the expression of the α7-acetylcholine receptor in the hippocampus. Also, the number of astrocytes increased in the anterior olfactory nucleus of the exposed mice. Taken together, these disturbances may contribute to the neurobehavioural impairments reported previously by us after IN GlyBH administration in mice., Competing Interests: Declaration of Competing Interest This research was supported by grants from Secretaría General de Ciencia y Tecnología-Universidad Nacional del Sur [PGI 24/B290] to AM and [PGI 24/B278] to CJB. The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)