Emily J. Jaehne , Emily J. Antolasic , Kerstin C. Creutzberg , Veronica Begni , Marco A. Riva , Maarten van den Buuse
{"title":"Impaired fear memory in a rat model of the brain-derived neurotrophic factor Val66Met polymorphism is reversed by chronic exercise","authors":"Emily J. Jaehne , Emily J. Antolasic , Kerstin C. Creutzberg , Veronica Begni , Marco A. Riva , Maarten van den Buuse","doi":"10.1016/j.nlm.2023.107779","DOIUrl":null,"url":null,"abstract":"<div><p><span><span>The brain-derived neurotrophic factor (BDNF) Val66Met polymorphism is associated with reduced activity-dependent BDNF release in the brain and has been implicated in fear and anxiety disorders, including post-traumatic stress disorder. Exercise has been shown to have benefits in affective disorders but the role of BDNF Val66Met remains unclear. Male and female BDNF Val66Met rats were housed in automated running-wheel cages from weaning while controls were housed in standard cages. During adulthood, all rats underwent standard three-day fear conditioning testing, with three tone/shock pairings on day 1 (acquisition), and extinction learning and memory (40 tones/session) on day 2 and day 3. Expression of BDNF and stress-related genes were measured in the frontal cortex. Extinction testing on day 2 revealed significantly lower freezing in response to initial cue exposure in control Met/Met rats, reflecting impaired fear memory. This deficit was reversed in both male and female Met/Met rats exposed to exercise. There were no genotype effects on acquisition or extinction of fear, however chronic exercise increased freezing in all groups at every stage of testing. Exercise furthermore led to increased expression of Bdnf in the </span>prefrontal cortex of females and its isoforms in both sexes, as well as increased expression of </span>FK506 binding protein 51 (Fkpb5) in females and decreased expression of Serum/glucocorticoid-regulated kinase (Sgk1) in males independent of genotype. These results show that the Met/Met genotype of the Val66Met polymorphism affects fear memory, and that chronic exercise selectively reverses this genotype effect. Chronic exercise also led to an overall increase in freezing in all genotypes which may contribute to results.</p></div>","PeriodicalId":19102,"journal":{"name":"Neurobiology of Learning and Memory","volume":"203 ","pages":"Article 107779"},"PeriodicalIF":2.2000,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Neurobiology of Learning and Memory","FirstCategoryId":"102","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1074742723000606","RegionNum":4,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"BEHAVIORAL SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
The brain-derived neurotrophic factor (BDNF) Val66Met polymorphism is associated with reduced activity-dependent BDNF release in the brain and has been implicated in fear and anxiety disorders, including post-traumatic stress disorder. Exercise has been shown to have benefits in affective disorders but the role of BDNF Val66Met remains unclear. Male and female BDNF Val66Met rats were housed in automated running-wheel cages from weaning while controls were housed in standard cages. During adulthood, all rats underwent standard three-day fear conditioning testing, with three tone/shock pairings on day 1 (acquisition), and extinction learning and memory (40 tones/session) on day 2 and day 3. Expression of BDNF and stress-related genes were measured in the frontal cortex. Extinction testing on day 2 revealed significantly lower freezing in response to initial cue exposure in control Met/Met rats, reflecting impaired fear memory. This deficit was reversed in both male and female Met/Met rats exposed to exercise. There were no genotype effects on acquisition or extinction of fear, however chronic exercise increased freezing in all groups at every stage of testing. Exercise furthermore led to increased expression of Bdnf in the prefrontal cortex of females and its isoforms in both sexes, as well as increased expression of FK506 binding protein 51 (Fkpb5) in females and decreased expression of Serum/glucocorticoid-regulated kinase (Sgk1) in males independent of genotype. These results show that the Met/Met genotype of the Val66Met polymorphism affects fear memory, and that chronic exercise selectively reverses this genotype effect. Chronic exercise also led to an overall increase in freezing in all genotypes which may contribute to results.
期刊介绍:
Neurobiology of Learning and Memory publishes articles examining the neurobiological mechanisms underlying learning and memory at all levels of analysis ranging from molecular biology to synaptic and neural plasticity and behavior. We are especially interested in manuscripts that examine the neural circuits and molecular mechanisms underlying learning, memory and plasticity in both experimental animals and human subjects.