Daily exercise improves memory, stimulates hippocampal neurogenesis and modulates immune and neuroimmune cytokines in aging rats

作者：Speisman Rachel B; Kumar Ashok; Rani Asha; Foster Thomas C; Ormerod Brandi K^*

来源：Brain, Behavior, and Immunity, 2013, 28: 25-43.

DOI：10.1016/j.bbi.2012.09.013

• Adult neurogenesis
• Hippocampus
• Running
• Cytokine
• Chemokine
• Biomarker
• Learning
• Memory
• Water maze
• Fisher 344
• Bio-Plex

We tested whether daily exercise modulates immune and neuroimmune cytokines, hippocampus-dependent behavior and hippocampal neurogenesis in aging male F344 rats (18mo upon arrival). Twelve weeks after conditioned running or control group assignment, the rats were trained and tested in a rapid water maze followed by an inhibitory avoidance task. The rats were BrdU-injected beginning 12 days after behavioral testing and killed 3 weeks later to quantify cytokines and neurogenesis. Daily exercise increased neurogenesis and improved immediate and 24 h water maze discrimination index (DI) scores and 24 h inhibitory avoidance retention latencies. Daily exercise decreased cortical VEGF, hippocampal IL-1 beta and serum MCP-1, GRO-KC and leptin levels but increased hippocampal GRO-KC and IL-18 concentrations. Serum leptin concentration correlated negatively with new neuron number and both DI scores while hippocampal IL-1 beta concentration correlated negatively with memory scores in both tasks. Cortical VEGF, serum GRO-KC and serum MCP-1 levels correlated negatively with immediate DI score and we found novel positive correlations between hippocampal IL-18 and GRO-KC levels and new neuron number. Pathway analyses revealed distinct serum, hippocampal and cortical compartment cytokine relationships. Our results suggest that daily exercise potentially improves cognition in aging rats by modulating hippocampal neurogenesis and immune and neuroimmune cytokine signaling. Our correlational data begin to provide a framework for systematically manipulating these immune and neuroimmune signaling molecules to test their effects on cognition and neurogenesis across lifespan in future experiments. Published by Elsevier Inc.

• 出版日期2013-2