Project description:Identifying secreted mediators driving the cognitive benefits of exercise holds great promise for the treatment of cognitive decline in aging or Alzheimer’s disease (AD). Here, we show that irisin, the cleaved and circulating form of the exercise-induced membrane protein FNDC5, is sufficient to confer the exercise benefits on cognitive function. Genetic deletion of FNDC5/irisin (global F5KO mice) impairs cognitive function in exercise, aging, and AD. Diminished pattern separation in F5KOs can be rescued by delivering irisin directly into the dentate gyrus, suggesting that irisin is the active moiety. In F5KOs, adult-born neurons in the dentate gyrus are morphologically, transcriptionally, and functionally abnormal. Importantly, elevation of circulating irisin levels by peripheral administration, resulting in enrichment of central irisin, was sufficient to improve both the cognitive deficit and neuropathology in AD mouse models. Irisin is a crucial regulator of cognitive benefits of exercise and potential therapeutic for treating cognitive disorders including AD.
Project description:Identifying secreted mediators driving the cognitive benefits of exercise holds great promise for the treatment of cognitive decline in aging or Alzheimer’s disease (AD). Here, we show that irisin, the cleaved and circulating form of the exercise-induced membrane protein FNDC5, is sufficient to confer the exercise benefits on cognitive function. Genetic deletion of FNDC5/irisin (global F5KO mice) impairs cognitive function in exercise, aging, and AD. Diminished pattern separation in F5KOs can be rescued by delivering irisin directly into the dentate gyrus, suggesting that irisin is the active moiety. In F5KOs, adult-born neurons in the dentate gyrus are morphologically, transcriptionally, and functionally abnormal. Importantly, elevation of circulating irisin levels by peripheral administration, resulting in enrichment of central irisin, was sufficient to improve both the cognitive deficit and neuropathology in AD mouse models. Irisin is a crucial regulator of cognitive benefits of exercise and potential therapeutic for treating cognitive disorders including AD.
Project description:Identifying secreted mediators driving the cognitive benefits of exercise holds great promise for the treatment of cognitive decline in aging or Alzheimer’s disease (AD). Here, we show that irisin, the cleaved and circulating form of the exercise-induced membrane protein FNDC5, is sufficient to confer the exercise benefits on cognitive function. Genetic deletion of FNDC5/irisin (global F5KO mice) impairs cognitive function in exercise, aging, and AD. Diminished pattern separation in F5KOs can be rescued by delivering irisin directly into the dentate gyrus, suggesting that irisin is the active moiety. In F5KOs, adult-born neurons in the dentate gyrus are morphologically, transcriptionally, and functionally abnormal. Importantly, elevation of circulating irisin levels by peripheral administration, resulting in enrichment of central irisin, was sufficient to improve both the cognitive deficit and neuropathology in AD mouse models. Irisin is a crucial regulator of cognitive benefits of exercise and potential therapeutic for treating cognitive disorders including AD.
Project description:The current study employed next-generation RNA sequencing to examine gene expression related to brain aging and cognitive decline. Young and aged rats were trained on a spatial episodic memory task. Hippocampal regions CA1, CA3 and the dentate gyrus (DG) were isolated. Poly-A mRNA was examined using two different platforms, Illumina and Ion Proton. The Illumina platform was used to generate lists of genes that were differentially expressed across regions, ages, and in association with cognitive function. The gene lists were then retested using the Ion Proton platform. The results describe regional differences in gene expression and point to regional differences in vulnerability to aging. Aging was associated with increased expression of immune response related genes, particularly in the dentate gyrus. Finally, for the memory task used, impaired performance of aged animals was linked to the regulation of Ca2+ and synaptic function in region CA1.