Evaluation of the neuroprotective potential of Trans-cinnamaldehyde in female Wistar rat model of insulin resistance

Abstract

Background: Chronic hyperglycemia in type 2 diabetes is associated with altered cognitive function. Trans-cinnamaldehyde (TCA) is one of the active components in cinnamon. It has been reported to have many pharmacological activities such as anti-bacterial and anti-inflammatory properties. Aim and Objectives: This present work evaluates the neuroprotective effects of TCA in the hippocampus of insulin-resistant rats. Material and Methods: Twenty female adult Wistar rats were fed with high fat diet for 8 weeks and then injected with a low dose of streptozotocin (30 mg/kg body weight intraperitoneally). Sixty mg/kg of TCA was orally administered for 4 weeks once daily. Y-maze and Morris water maze tests were employed to test for learning and memory. Fasting blood glucose, serum insulin, hippocampal Tumor Necrosis Factor-α (TNF-α), Nuclear Factor κB (NF‐κB) were assayed. Results: The high fat diet/streptozotocin-induced insulin resistant-rats, characterized by hyperglycemia and hyperinsulinemia performed poorly in the Y-maze and Morris water maze (38.17 ± 1.3 s) when compared with the controls (26.67 ± 1.4 s), suggesting the impairment of learning and memory with corresponding increase in NF‐κB and TNF-α in the hippocampus. Conclusion: Treatment with TCA significantly reversed diabetes‐induced impairment of learning and memory. TCA as a prospective novel therapy in insulin-resistant subjects with dementia could be further explored.

Keywords

• hippocampus
• trans-cinnamaldehyde
• insulin resistance
• neuro-inflammation