Chronic Lead Exposure Results in Auditory Deficits and Disruption of Hair Cells in Postweaning Rats
| Autor: | Shi-Zhong Cai, Shou-Sen Hu, Xiang-Zhen Kong |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Aging
medicine.medical_specialty Article Subject Glutathione reductase medicine.disease_cause Biochemistry Superoxide dismutase chemistry.chemical_compound Internal medicine Hair Cells Auditory medicine Evoked Potentials Auditory Brain Stem otorhinolaryngologic diseases Animals lcsh:QH573-671 Cochlea Spiral ganglion chemistry.chemical_classification biology lcsh:Cytology Glutathione peroxidase Cell Biology General Medicine Glutathione Rats medicine.anatomical_structure Endocrinology chemistry Lead Lead acetate Chronic Disease biology.protein sense organs Oxidative stress Research Article |
| Zdroj: | Oxidative Medicine and Cellular Longevity Oxidative Medicine and Cellular Longevity, Vol 2019 (2019) |
| ISSN: | 1942-0900 |
| DOI: | 10.1155/2019/4289169 |
| Popis: | Objective.The effects of lead exposure on cognitive function have been studied intensively over the past decade, but less attention has focused on its impact on auditory function. This study is aimed at investigating the effect of lead on the cochlea and the molecular mechanisms responsible for its actions.Methods.0.2% lead acetate was administered to rats in drinking water for 30, 60, and 90 days. Brainstem auditory evoked responses (ABR) were recorded, and morphological changes in the hair cells were observed. We also measured glutathione (GSH) and malondialdehyde (MDA) concentrations and antioxidant enzyme activities such as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione reductase (GR) activities in the cochlea.Results.Lead exposure increased the ABR threshold and slightly prolonged the latencies of wave II and wave IV in rats. Abnormally shaped hair cells and loss of hair cells were found in the cochlea basilar membrane, together with degenerative changes in spiral ganglion neurons following lead exposure. The activities of some antioxidant enzymes were also reduced in association with upregulation of MDA expression. These effects may be caused by impaired catalytic function of the enzymes as a result of lead interaction.Conclusion.The antioxidant system of the cochlea in the immature rat brain is highly vulnerable to developmental lead exposure. Oxidative stress may therefore represent a possible mechanism for lead-induced auditory deficits. |
| Databáze: | OpenAIRE |
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