title: Effects of BDNF polymorphism and physical activity on episodic memory in the elderly: a cross sectional study.
abstract: BACKGROUND
  The brain-derived neurotrophic factor (BDNF) concentration is highest in the hippocampus compared with that in other brain structures and affects episodic memory, a cognitive function that is impaired in older adults. According to the neurotrophic hypothesis, BDNF released during physical activity enhances brain plasticity and consequently brain health. However, even if the physical activity level is involved in the secretion of neurotrophin, this protein is also under the control of a specific gene. The aim of the present study was to examine the effect of the interaction between physical activity and BDNF Val66Met (rs6265), a genetic polymorphism, on episodic memory.
  
  
  METHODS
  Two hundred and five volunteers aged 55 and older with a Mini Mental State Examination score ≥ 24 participated in this study. Four groups of participants were established according to their physical activity level and polymorphism BDNF profile (Active Val homozygous, Inactive Val homozygous, Active Met carriers, Inactive Met carriers). Episodic memory was evaluated based on the delayed recall of the Logical Memory test of the MEM III battery.
  
  
  RESULTS
  As expected, the physical activity level interacted with BDNF polymorphism to affect episodic memory performance (p < .05). The active Val homozygous participants significantly outperformed the active Met carriers and inactive Val homozygous participants.
  
  
  CONCLUSIONS
  This study clearly demonstrates an interaction between physical activity and BDNF Val66Met polymorphism that affects episodic memory in the elderly and confirms that physical activity contributes to the neurotrophic mechanism implicated in cognitive health. The interaction shows that only participants with Val/Val polymorphism benefited from physical activity.
authors: Université de Poitiers, Centre de Recherches sur la Cognition et l'Apprentissage, CNRS UMR 7295, Poitiers, France.
authors: Anne
authors: A
authors: Canivet
authors: Université de Poitiers, Centre de Recherches sur la Cognition et l'Apprentissage, CNRS UMR 7295, Poitiers, France ; Institut National Universitaire Champollion, Place Verdun, 81000 Albi, France.
authors: Cédric T
authors: CT
authors: Albinet
authors: Université de Poitiers, Centre de Recherches sur la Cognition et l'Apprentissage, CNRS UMR 7295, Poitiers, France.
authors: Nathalie
authors: N
authors: André
authors: Université de Poitiers, Centre de Recherches sur la Cognition et l'Apprentissage, CNRS UMR 7295, Poitiers, France.
authors: Jean
authors: J
authors: Pylouster
authors: Université de Poitiers, CHU de Poitiers, Laboratoire CiMoTheMA - EA 3808 Groupe « Génétique des maladies rares », Poitiers, France.
authors: Montserrat
authors: M
authors: Rodríguez-Ballesteros
authors: Université de Poitiers, CHU de Poitiers, Laboratoire CiMoTheMA - EA 3808 Groupe « Génétique des maladies rares », Poitiers, France.
authors: Alain
authors: A
authors: Kitzis
authors: Université de Poitiers, Centre de Recherches sur la Cognition et l'Apprentissage, CNRS UMR 7295, Poitiers, France ; Université de Poitiers, Maison des Sciences de l'Homme et de la Société, CNRS USR 3565, Poitiers, France.
authors: Michel
authors: M
authors: Audiffren
keywords: Aging; BDNF Val66Met polymorphism; Cognition; Episodic memory; Physical activity