背景:断奶后是大脑发育和个体生长的关键时期。作为一种重要的药物,食品和饮料,柠檬酸钠(SC)是常见的。尽管已经证明了SC暴露对个体生理的一些影响,断奶后膳食SC暴露对社会行为的潜在长期影响仍然难以捉摸.
方法:断奶后雄性和雌性C57BL/6小鼠均通过饮用水暴露于SC,共3周。一系列的行为测试,包括社会支配能力测试(SDT),社交互动测试(SIT),床上用品偏好测试(BPT)和性偏好测试(SPT),在青春期和成年期进行。经过这些测试,检测血清催产素(OT)水平和肠道菌群。
结果:行为结果显示,断奶后SC暴露降低了成年雄性小鼠和青春期和成年期雌性小鼠的社会优势。SC暴露也降低了男性和女性的性偏好率,虽然它对社会互动行为没有影响。ELISA结果表明,SC暴露降低了女性的血清OT水平,而不是男性。16SrRNA测序分析显示,男性和女性暴露于SC后,β多样性存在显着差异。相关系数表明社会行为之间的相关性,肠道菌群的OT水平和优势属。
结论:我们的研究结果表明,断奶后SC暴露可能对社会行为产生持久和性别依赖的影响,这可能与血清OT水平和肠道菌群组成的改变有关。
BACKGROUND: Postweaning is a pivotal period for brain development and individual growth. As an important chemical used in medicines, foods and beverages, sodium citrate (SC) is commonly available. Although some effects of SC exposure on individual physiology have been demonstrated, the potential long-lasting effects of postweaning dietary SC exposure on social behaviours are still elusive.
METHODS: Both postweaning male and female C57BL/6 mice were exposed to SC through drinking water for a total of 3 weeks. A series of behavioural tests, including social dominance test (SDT), social interaction test (SIT), bedding preference test (BPT) and sexual preference test (SPT), were performed in adolescence and adulthood. After these tests, serum oxytocin (OT) levels and gut microbiota were detected.
RESULTS: The behavioural results revealed that postweaning SC exposure decreased the social dominance of male mice in adulthood and female mice in both adolescence and adulthood. SC exposure also reduced the sexual preference rates of both males and females, while it had no effect on social interaction behaviour. ELISA results indicated that SC exposure decreased the serum OT levels of females but not males. 16S rRNA sequencing analysis revealed a significant difference in β-diversity after SC exposure in both males and females. The correlation coefficient indicated the correlation between social behaviours, OT levels and dominant genera of gut microbiota.
CONCLUSIONS: Our findings suggest that postweaning SC exposure may have enduring and sex-dependent effects on social behaviours, which may be correlated with altered serum OT levels and gut microbiota composition.