Brain effect of insulin and clonazepam in diabetic rats under depressive-like behavior
Diabetes mellitus is characterized by hyperglycemia resulting from defects on insulin secretion, insulin action, or both. It has recently become clear that the central nervous system is not spared from the deleterious effects of diabetes, since diabetic encephalopathy was recognized as a complication of this heterogeneous metabolic disorder. There is a well recognized association between depression and diabetes, once prevalence of depression in diabetic patients is higher than in general population, and clonazepam is being used to treat this complication. Oxidative stress is widely accepted as playing a key mediatory role in the development and progression of diabetes and its complications. In this work we analyzed DNA damage by comet assay and lipid damage in prefrontal cortex, hippocampus and striatum of streptozotocin-induced diabetic rats submitted to the forced swimming test. It was verified that the diabetic group presented DNA and lipid damage in the brain areas evaluated, when compared to the control groups. Additionally, a significant reduction of the DNA and lipid damage in animals treated with insulin and/or clonazepam was observed. These data suggest that the association of these two drugs could protect against DNA and lipid damage in diabetic rats submitted to the forced swimming test, an animal model of depression.
KeywordsBrain Comet assay Depression Diabetes Lipid damage Oxidative stress
We thank Mario Serapião for his technical support. We also appreciate the financial support from Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) and Fundo de Incentivo à Pesquisa e Eventos do Hospital de Clínicas de Porto Alegre (FIPE/HCPA). CRV is the recipient of a CNPq 2 Researcher Productivity Grant. HMTB is the recipient of a CNPq 1C Researcher Productivity Grant, and CAYW and CPM are recipients of fellowships from the CNPq or CAPES.
Conflict of interest
The authors declare that there are no conflicts of interest including any financial, personal or other relationships with other people or organizations.
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