Durán-Carabali L E, Arcego D M, Sanches E F, Odorcyk F K, Marques M R, Tosta A, Reichert L, Carvalho A S, Dalmaz C, Netto C A
Post-Graduation Program of Physiology, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
Department of Biochemistry, Instituto de Ciências Básicas da Saúde (ICBS), Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
Behav Brain Res. 2019 Feb 1;359:485-497. doi: 10.1016/j.bbr.2018.11.036. Epub 2018 Nov 26.
Environmental enrichment (EE) at early stages of neurodevelopment attenuates HI-induced behavioral, histological and cellular damage. However, the effects of EE exposure during gestational or early postnatal period and the possible influence of sexual dimorphism on EE protection are not fully understood. Present study evaluated the effects of pre-natal and postnatal EE, as well as their combination, in male and female rats submitted to neonatal HI at postnatal day (PND) 3. Wistar rats were housed in EE or in standard condition (SC) during all pregnancy. At PND1, the litters were randomly allocated to the same prenatal environment during lactation (SC + SC or EE + EE) or housed in a new environment until weaning (SC + EE or EE + SC). Behavioral tasks were performed from PND 60-75. Then, animals were euthanized for biochemical and histological analysis. Prenatal and early postnatal EE alone improved performance of HI males in the Water Maze spatial memory task, while HI females were most benefited from early postnatal stimulation. Moreover, EE attenuated HI-induced lower anxiety-like behavior in rats of both sexes and decreased hyperlocomotion in HI females. Hippocampus tissue preservation and higher VEGF and TrkB levels were observed in all HI groups exposed to EE. Interestingly, HI males exposed to prenatal or postnatal EE alone exhibited higher GFAP levels and additional tissue preservation. Therefore, both prenatal and early postnatal environmental enrichment cause attenuation of HI-induced impairments, revealing their preventive and therapeutic actions, possibly due to VEGF and astrocyte activity; some of these effects are sex-specific.
神经发育早期的环境富集(EE)可减轻缺氧缺血(HI)诱导的行为、组织学和细胞损伤。然而,孕期或出生后早期暴露于EE的影响以及性别差异对EE保护作用的可能影响尚未完全明确。本研究评估了产前和产后EE及其联合作用对出生后第3天经历新生儿HI的雄性和雌性大鼠的影响。所有孕期,Wistar大鼠被饲养在EE环境或标准条件(SC)下。在出生后第1天,将幼崽随机分配到与产前相同的哺乳环境(SC + SC或EE + EE),或饲养在新环境中直至断奶(SC + EE或EE + EE)。在出生后第60 - 75天进行行为测试。然后,对动物实施安乐死以进行生化和组织学分析。单独的产前和产后早期EE改善了HI雄性大鼠在水迷宫空间记忆任务中的表现,而HI雌性大鼠从产后早期刺激中获益最多。此外,EE减轻了HI诱导的两性大鼠的低焦虑样行为,并减少了HI雌性大鼠的运动亢进。在所有暴露于EE的HI组中均观察到海马组织保存以及更高的血管内皮生长因子(VEGF)和酪氨酸激酶受体B(TrkB)水平。有趣的是,单独暴露于产前或产后EE的HI雄性大鼠表现出更高的胶质纤维酸性蛋白(GFAP)水平和额外的组织保存。因此,产前和产后早期的环境富集均减轻了HI诱导的损伤,揭示了它们的预防和治疗作用,这可能归因于VEGF和星形胶质细胞的活性;其中一些作用具有性别特异性。