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da Silva DRF, Bittencourt LO, Aragão WAB, Nascimento PC, Leão LKR, Oliveira ACA, Crespo-López ME, Lima RR. Long-term exposure to lead reduces antioxidant capacity and triggers motor neurons degeneration and demyelination in spinal cord of adult rats. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 194:110358. [PMID: 32151863 DOI: 10.1016/j.ecoenv.2020.110358] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 02/17/2020] [Accepted: 02/18/2020] [Indexed: 06/10/2023]
Abstract
Lead is a toxic metal found in environment with great neurotoxic potential. The main effect is associated with impairments in hippocampus and cerebellum, driving to cognitive and motor dysfunctions, however, there is a lack of evidences about the effects over the spinal cord. In this way, we aimed to investigate in vivo the effects of long-term exposure to lead acetate in oxidative biochemistry and morphology of rats' spinal cord. For this, 36 male Wistar rats (Rattus norvegicus) were divided into the group exposed to 50 mg/kg of lead acetate and control group, which received only distilled water, both groups through intragastric gavage, for 55 days. After the exposure period, the animals were euthanized and the spinal cords were collected to perform the analyses of lead levels quantification, oxidative biochemistry evaluation by levels of malondialdehyde (MDA), nitrites and the antioxidant capacity against peroxyl radicals (ACAP). Besides, morphological evaluation with quantitative analysis of mature and motor neurons and reactivity to myelin basic protein (MBP). Our results showed high levels of lead in spinal cord after long-term exposure; there was a reduction on ACAP level; however, there was no difference observed in MDA and nitrite levels. Moreover, there was a reduction of mature and motor neurons in all three regions, and a reduction of immunolabeling of MBP in the thoracic and lumbar segments. Therefore, we conclude that long-term exposure to lead is able of increasing the levels of the metal in spinal cord, affecting the antioxidant capacity and inducing morphological impairments in spinal cord parenchyma. Our results also suggest that the tissue impairments triggered by lead may be resultant from others molecular mechanisms besides the oxidative stress.
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Affiliation(s)
- Dannilo Roberto Ferreira da Silva
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, State of Pará, Brazil
| | - Leonardo Oliveira Bittencourt
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, State of Pará, Brazil
| | - Walessa Alana Bragança Aragão
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, State of Pará, Brazil
| | - Priscila Cunha Nascimento
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, State of Pará, Brazil
| | - Luana Ketlen Reis Leão
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, State of Pará, Brazil
| | - Ana Carolina Alves Oliveira
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, State of Pará, Brazil
| | - Maria Elena Crespo-López
- Laboratory of Molecular Pharmacology, Institute of Biological Sciences, Federal University of Pará, Belém, State of Pará, Brazil
| | - Rafael Rodrigues Lima
- Laboratory of Functional and Structural Biology, Institute of Biological Sciences, Federal University of Pará, Belém, State of Pará, Brazil.
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Villa-Cedillo SA, Nava-Hernández MP, Soto-Domínguez A, Hernández-Ibarra JA, Perez-Trujillo JJ, Saucedo-Cárdenas O. Neurodegeneration, demyelination, and astrogliosis in rat spinal cord by chronic lead treatment. Cell Biol Int 2019; 43:706-714. [PMID: 30977573 DOI: 10.1002/cbin.11147] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 03/28/2019] [Accepted: 04/06/2019] [Indexed: 12/13/2022]
Abstract
Early exposure to lead (Pb) has been associated with an elevated risk of developing neurodegenerative diseases. There is evidence that neuronal damage in chronic Pb exposure can be caused by the convergence of glial damage. Apoptosis may be a possible mechanism of Pb-induced cell death in the central nervous system. We tested cellular damage and apoptosis in the spinal cord of Wistar rats treated with Pb. Twelve rats were divided into two groups (n = 6): the control group was treated with only drinking water and the other group received 500 ppm of Pb acetate. After 3 months of Pb treatment, all animals were euthanized and spinal cords were extracted. Morphology was evaluated by Nissl and Kluver-Barrera stainings. Apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Specific antibodies were used to evaluate Pb damage in oligodendrocytes, astrocytes, and microglia. A large number of apoptotic bodies was observed in the white matter of the Pb-treated group. The Pb-treated group also showed a reduced number of neurons and oligodendrocytes but had an increased number of astrocytes compared with the nontreated group. Our results demonstrate that chronic Pb treatment induces neurodegeneration, demyelination, and astrogliosis in the rat spinal cord.
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Affiliation(s)
- Sheila Adela Villa-Cedillo
- Departamento de Histología, Facultad de Medicina, Universidad Autónoma de Nuevo León (UANL), Madero y Dr. Aguirre Pequeño, Mitras Centro, 64460, Monterrey, Nuevo León, México
| | - Martha Patricia Nava-Hernández
- Departamento de Biología de la Reproducción, Centro de Investigación Biomédica, Facultad de Medicina, Universidad Autónoma de Coahuila, Calle A. García 198 Sur, 27000, Torreón, Coahuila, México
| | - Adolfo Soto-Domínguez
- Departamento de Histología, Facultad de Medicina, Universidad Autónoma de Nuevo León (UANL), Madero y Dr. Aguirre Pequeño, Mitras Centro, 64460, Monterrey, Nuevo León, México
| | - José Anselmo Hernández-Ibarra
- Departamento de Biología de la Reproducción, Centro de Investigación Biomédica, Facultad de Medicina, Universidad Autónoma de Coahuila, Calle A. García 198 Sur, 27000, Torreón, Coahuila, México
| | - José Juan Perez-Trujillo
- Departamento de Histología, Facultad de Medicina, Universidad Autónoma de Nuevo León (UANL), Madero y Dr. Aguirre Pequeño, Mitras Centro, 64460, Monterrey, Nuevo León, México
| | - Odila Saucedo-Cárdenas
- Departamento de Histología, Facultad de Medicina, Universidad Autónoma de Nuevo León (UANL), Madero y Dr. Aguirre Pequeño, Mitras Centro, 64460, Monterrey, Nuevo León, México.,Departamento de Genética Molecular, Centro de Investigación Biomédica del Noreste, Instituto Mexicano del Seguro Social (IMSS), 2 de abril con San Luis Potosí, Colonia Independencia, 64460, Monterrey, Nuevo León, México
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