Mahnaz Bayat1, Kristi A Kohlmeier2, Masoud Haghani3, Afshin Borhani Haghighi1, Azadeh Khalili4, Gholamreza Bayat5, Etrat Hooshmandi1, Mohammad Shabani6. 1. Clinical Neurology Research Centre, Shiraz University of Medical Sciences, Shiraz, Iran. 2. Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, 2100, Copenhagen, Denmark. 3. Histomorphometry and Stereology Research Centre, Shiraz University of Medical Sciences, Shiraz, Iran. 4. Evidence-Based Phytotherapy and Complementary Medicine Research Center, Alborz University of Medical Sciences, Karaj, Iran. 5. Department of Physiology and Pharmacology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran. 6. Neuroscience Research Center, Neuropharmacology Institute, Kerman University of Medical Sciences, Kerman, Iran. shabani@kmu.ac.ir.
Abstract
RATIONALE AND OBJECTIVE: Environmental enrichment (EE) has been shown in old rats to improve learning and memory. Vitamin D (VitD) has also been shown to modulate age-related, cognitive dysfunction. As both EE and VitD could work to improve cognition via enhancement of neurotrophic factors, their effects might occlude one another. Therefore, a clinically relevant question is whether noted cognition-promoting effects of EE and VitD can co-occur. METHODS: Aged rats were housed for 6 weeks in one of three housing conditions: environmentally enriched (EE), socially enriched (SE), or standard condition (SC). Further, a 4th group was co-treated with VitD supplementation (400 IU kg-1 daily, 6 weeks) under EE conditions (EE + VitD). RESULTS: Treatment with VitD and EE housing were associated with higher score on measures of learning and memory and exhibited lower anxiety scores compared to EE alone, SE or SC as assayed in the elevated plus maze, Morris water maze, passive avoidance, and open field tasks. Additionally, in the EE + VitD group, mRNA expression levels of NGF, TrkA, BDNF, Nrf2, and IGF-1 were significantly higher compared to expression seen in the EE group. Furthermore, field potential recordings showed that EE + VitD resulted in a greater enhancement of hippocampal LTP and neuronal excitability when compared to EE alone. CONCLUSIONS: These findings demonstrate that in aged rats exposure to EE and VitD results in effects on hippocampal cognitive dysfunction and molecular mechanisms which are greater than effects of EE alone, suggesting potential for synergistic therapeutic effects for management of age-related cognitive decline.
RATIONALE AND OBJECTIVE: Environmental enrichment (EE) has been shown in old rats to improve learning and memory. Vitamin D (VitD) has also been shown to modulate age-related, cognitive dysfunction. As both EE and VitD could work to improve cognition via enhancement of neurotrophic factors, their effects might occlude one another. Therefore, a clinically relevant question is whether noted cognition-promoting effects of EE and VitD can co-occur. METHODS: Aged rats were housed for 6 weeks in one of three housing conditions: environmentally enriched (EE), socially enriched (SE), or standard condition (SC). Further, a 4th group was co-treated with VitD supplementation (400 IU kg-1 daily, 6 weeks) under EE conditions (EE + VitD). RESULTS: Treatment with VitD and EE housing were associated with higher score on measures of learning and memory and exhibited lower anxiety scores compared to EE alone, SE or SC as assayed in the elevated plus maze, Morris water maze, passive avoidance, and open field tasks. Additionally, in the EE + VitD group, mRNA expression levels of NGF, TrkA, BDNF, Nrf2, and IGF-1 were significantly higher compared to expression seen in the EE group. Furthermore, field potential recordings showed that EE + VitD resulted in a greater enhancement of hippocampal LTP and neuronal excitability when compared to EE alone. CONCLUSIONS: These findings demonstrate that in aged rats exposure to EE and VitD results in effects on hippocampal cognitive dysfunction and molecular mechanisms which are greater than effects of EE alone, suggesting potential for synergistic therapeutic effects for management of age-related cognitive decline.
Authors: A Acheson; J C Conover; J P Fandl; T M DeChiara; M Russell; A Thadani; S P Squinto; G D Yancopoulos; R M Lindsay Journal: Nature Date: 1995-03-30 Impact factor: 49.962
Authors: Mamun Al-Amin; DanaKai Bradford; Robert K P Sullivan; Nyoman D Kurniawan; Yeonsil Moon; Seol-Heui Han; Andrew Zalesky; Thomas H J Burne Journal: Hum Brain Mapp Date: 2018-09-25 Impact factor: 5.038