The effect of curcumin on brain trpm2 channel gene mRNA expression level in experimental alzheimer's rat model induced by application of intracerebroventricular streptozotocin

Aim: Streptozocin generates insulin-resistant condition in rat brain which forms Alzheimer-like pathology and it has approved successful as experimental rat model. It has been shown that curcumin has protective and therapeutic features as reduced oxidative stress and amyloid plaques in experimental Alzheimer rat models. TRPM2 channel protein has a negative effect on Alzheimer pathology with intrinsic calcium influx into the neurons. It has been reported in recent studies that curcumin could inhibit induced TRPM2 channel protein in vitro. The aim of this study is to investigate the effect of curcumin toTRPM2 gene and Alzheimer pathologyin Alzheimer rat model as in vivo. Material and Method: This study was carried out with 50 Wistar albino male rats. Analysis of experimental Alzheimer rat model performed by Morris water maze. Biochemical analysis like SOD, MDA, GSH with rat brain tissue accomplished by spectrophotometric methods. TRPM2 and MAPT gene expression levels performed by q-real time-PCR in rat hippocampus tissue. Hematoxylin-eosin staining made on brain tissues for histopathological analysis. Results: MDA levels increased in STZ group to STZ+curcumin. It was found GSH levels decreased in STZ group while STZ+curcumin increased (P < 0.05). SOD activities were higher in STZ group comparing to STZ+curcumin (P< 0.05). TRPM2 mRNA levels increased in STZ rats and has lower levels in STZ+curcumin. Histopathologically, STZ group had neurodegeneration and STZ+curcumin had attenuated damage. Conclusion: It has been shown that oxidative stress and neurodegeneration and increased TRPM2 mRNA levels in STZ induced rats. Curcumin has leaded to a reduction in TRPM2 mRNA levels with positive effect on neurodegeneration. Key Words: Alzheimer's disease, curcumin, rat, streptozotocin, TRPM2