Abstract
Aims/Introduction
Defective insulin signaling in the brain may disrupt hippocampal neuroplasticity resulting in learning and memory impairments. Thus, this study investigated the effect of aerobic exercise training on cognitive function and synaptic protein markers in diabetic rats.
Materials and methods
Twenty male Wistar rats (200–250 g), were fed on high-fat diet and received a low dose of streptozotocin (35 mg/kg, i.p) to induce type 2 diabetes. Then diabetic animals were randomly divided into sedentary and training groups. The exercise training program was treadmill running at 27 m/min for 60 min/day for 8 weeks. One day after the last training session, Morris Water Maze (MWM) task was performed to evaluate spatial learning and memory. Then, the hippocamp and prefrontal cortex tissues were instantly dissected for immunoblotting assay of BDNF, GSK-3β, p-GSK-3β, P38, p-P38, ERK1/2, p-ERK1/2, heat shock protein-27 (HSP27), SNAP-25, synaptophysin, and PSD-95. Independent t-test analysis and two-way ANOVA was used to determine the differences under significance level of 0.05 using the 26th version of IBM SPSS statistical software.
Results
The results showed that aerobic exercise improved memory as assessed in the MWM task. Moreover, aerobic exercise up-regulated HSP27 and BDNF protein levels in the prefrontal cortex, and hippocampus coincided with robust elevations in SNAP25 and PSD-95 levels. Moreover, exercise reduced phosphorylated P38, while increased p-ERK1/2 and p-GSK-3β (p).
Conclusion
Our findings suggest that aerobic exercise may debilitate the harmful effects of diabetes on the cognitive function possibly through enhancing synaptic protein markers.
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Data availability
Data are all contained within the article.
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Acknowledgements
We are grateful to the Neurosciences Research Center (NSRC), Tabriz University of Medical Sciences, especially Dr. Farhoudi for their laboratory equipment, exercise facilities, and technical support.
Funding
The fund for this study was provided by Dr. Iraj Sadri. This fund was used to purchase the necessary supplies. Authors also declare that no funds, grants, or other support were received during the preparation of this manuscript from other organizations or institutes.
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I.S. designed and performed research, analyzed data, and wrote the manuscript. S.D.N. contributed new reagents, and analytical tools and analyzed data and reviewed and edited the manuscript. P.K. analyzed data, and contributed to the discussion and reviewed and edited the manuscript. M.K. designed research, analyzed data, contributed to the discussion, and reviewed and edited the manuscript. S.N. Cooperated in running exercise protocol and data extraction, analyzed data, and wrote the manuscript I.S. is the sponsor of this work and has full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
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This study was approved by the research ethics committee (REC) of Tabriz University of Medical Sciences (TUOMS) (IR.TBZMED.REC.1395.1225).
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Sadri, I., Nikookheslat, S.D., Karimi, P. et al. Aerobic exercise training improves memory function through modulation of brain-derived neurotrophic factor and synaptic proteins in the hippocampus and prefrontal cortex of type 2 diabetic rats. J Diabetes Metab Disord (2023). https://doi.org/10.1007/s40200-023-01360-9
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DOI: https://doi.org/10.1007/s40200-023-01360-9