Caroline B Quines1, Suzan G Rosa1, Juliana T Da Rocha1, Bibiana M Gai1, Cristiani F Bortolatto1, Marta Maria M F Duarte2, Cristina W Nogueira3. 1. Laboratório de Síntese, Reatividade e Avaliação Farmacológica e Toxicológica de Organocalcogênios, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Santa Maria, CEP 97105-900, Rio Grande do Sul, Brazil. 2. Departamento de Ciências da Saúde, Universidade Luterana do Brasil, Santa Maria, Rio Grande do Sul, Brazil. 3. Laboratório de Síntese, Reatividade e Avaliação Farmacológica e Toxicológica de Organocalcogênios, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Santa Maria, CEP 97105-900, Rio Grande do Sul, Brazil. Electronic address: criswn@quimica.ufsm.br.
Abstract
UNLABELLED: Monosodium glutamate (MSG) has been the target of research due to its toxicological effects. AIMS: We investigated the depressive- and anxiogenic-like behaviors in rats exposed to neonatal subcutaneous injection of MSG. The involvement of the serotonergic system, by measuring [(3)H] serotonin (5-HT) uptake in cerebral cortices, and the hypothalamic pituitary adrenal (HPA) axis, by determining serum adrenocorticotropic hormone (ACTH) and corticosterone levels, was also examined. MATERIALS AND METHODS: Male and female newborn Wistar rats were divided into control and MSG groups, which received, respectively, a daily subcutaneous injection of saline (0.9%) or MSG (4 g/kg/day) from the 1st to 5th postnatal day. The behavioral tests [spontaneous locomotor activity, contextual fear conditioning, and forced swimming test (FST)] were performed from the 60th to 64th postnatal day. MSG-treated animals showed alteration in the spontaneous locomotor activity, an increase in the number of fecal pellets and the number of animal's vocalizations and urine occurrence, and a decrease in the grooming time. KEY FINDINGS: The MSG exposure increased the immobility time in the FST and the freezing reaction in the contextual fear conditioning. Additionally, MSG treatment increased the [(3)H]5-HT uptake in the cerebral cortices of rats and induced a deregulation of HPA axis function (by increasing serum ACTH and corticosterone levels). SIGNIFICANCE: In conclusion MSG-treated rats are more susceptible to develop anxiogenic- and depressive-like behaviors, which could be related to a dysfunction in the serotonergic system.
UNLABELLED: Monosodium glutamate (MSG) has been the target of research due to its toxicological effects. AIMS: We investigated the depressive- and anxiogenic-like behaviors in rats exposed to neonatal subcutaneous injection of MSG. The involvement of the serotonergic system, by measuring [(3)H] serotonin (5-HT) uptake in cerebral cortices, and the hypothalamic pituitary adrenal (HPA) axis, by determining serum adrenocorticotropic hormone (ACTH) and corticosterone levels, was also examined. MATERIALS AND METHODS: Male and female newborn Wistar rats were divided into control and MSG groups, which received, respectively, a daily subcutaneous injection of saline (0.9%) or MSG (4 g/kg/day) from the 1st to 5th postnatal day. The behavioral tests [spontaneous locomotor activity, contextual fear conditioning, and forced swimming test (FST)] were performed from the 60th to 64th postnatal day. MSG-treated animals showed alteration in the spontaneous locomotor activity, an increase in the number of fecal pellets and the number of animal's vocalizations and urine occurrence, and a decrease in the grooming time. KEY FINDINGS: The MSG exposure increased the immobility time in the FST and the freezing reaction in the contextual fear conditioning. Additionally, MSG treatment increased the [(3)H]5-HT uptake in the cerebral cortices of rats and induced a deregulation of HPA axis function (by increasing serum ACTH and corticosterone levels). SIGNIFICANCE: In conclusion MSG-treated rats are more susceptible to develop anxiogenic- and depressive-like behaviors, which could be related to a dysfunction in the serotonergic system.
Authors: Ethel Antunes Wilhelm; Cristiane Luchese; Karline C Rodrigues; Cristiani F Bortolatto; Ketlyn P da Motta; Renata L de Oliveira; Jaini J Paltian; Roberta Krüger; Silvane S Roman; Silvana P Boeira; Diego Alves Journal: Psychopharmacology (Berl) Date: 2021-03-19 Impact factor: 4.530
Authors: Pooja Kumar; A Zarina Kraal; Andreas M Prawdzik; Allison E Ringold; Vicki Ellingrod Journal: Front Psychiatry Date: 2021-01-21 Impact factor: 4.157