Effects of creatine supplementation on learning, memory retrieval, and apoptosis in an experimental animal model of Alzheimer disease

Background: Alzheimer disease is the main cause of dementia in middle-aged and elderly people. Considering the improving effects of creatine supplementation on cognitive performance, this study aimed to determine the effects of creatine supplementation on learning, memory, and apoptosis in an experimental model of Alzheimer’s disease. Methods: Thirty-two male Wistar rats each weighing 250±50 grams were divided into four groups. The AdCr+ (A&beta injection, creatine supplementation) and AdCr- groups (A&beta injection, no creatine supplementation) were injected bilaterally with amyloid beta (A&beta) (0.2µg in each CA1 area), and the sham group was injected with normal saline in the same area. After the injection, the AdCr+ group received a diet of 2% creatine for six weeks. The control group underwent no surgical or dietary intervention. After six weeks the Morris Water Maze (MWM) test was administered, to measure learning and memory retrieval. After sacrificing the animals, TUNEL staining for an anti-apoptosis assay was performed for the sham, AdCr+, and AdCr- groups. All groups were compared by independent t-test using SPSS software. Results: Results of MWM show that rats in sham and control groups performed better than those in the AdCr- and AdCr+ groups. Compared to sham group, AdCr+ and AdCr- groups had more TUNEL positive neurons count.  Results indicated no differences between the AdCr+ and AdCr- groups in learning, memory retrieval, and percentage of TUNEL positive neurons. Conclusion: After A&beta injection, creatine supplementation had no effect on learning, memory retrieval, or neuron apoptosis in male Wistar rats.