Background

The function of gut microbiota as its role in normal physiology and involvement in brain function has gained a great deal of attention. The potential long-lasting effects of postweaning sodium butyrate (SB) exposure on social behaviors are still unknown; however it acts as one of the metabolites of gut microbiota.

Methods

Male mice (24-day old) were exposed to SB through drinking water for 21 continuous days. A series of behavioral tests, mainly including bedding preference test (BP), sexual preference test (SP), social interaction test (SI), tube dominance test (SDT), forced swimming test (FST), open field test (OFT), novel object recognition task (NOR) were conducted at different time after 21-d SB exposure. Serum Trimethylamine oxide (TMAO) levels were investigated to gain insight into a potential mechanism.

Results

Behavioral results indicated that postweaning SB exposure significantly decreased the social dominance status of low-ranked mice and decreased the sexual preference without affecting social interaction. SB exposure also exerted transient anxiolytic-like effects, while having induced a long-lasting depression-like effect without effects on memory formation. Postweaning SB exposure increased serum TMAO levels in mice, especially in lower-ranked mice, but decreased in higher-ranked mice.

Limitations

Lack of understanding of the underlying mechanism.

Conclusions

These findings provide direct evidence, for the first time, that postweaning SB exposure produces long-term effects on social behaviors in adult mice, mainly referring to sexual orientation, social dominance, and depression-like behaviors, which may be related to the serum TMAO levels, highlighting the long-lasting potential effects of gut-brain interaction on social behaviors.

中文翻译：

---

断奶后丁酸钠暴露对成年小鼠社会行为的长期影响

背景

肠道微生物群在正常生理和大脑功能中的作用已引起广泛关注。断奶后丁酸钠 (SB) 暴露对社会行为的潜在长期影响仍然未知；然而，它是肠道微生物群的代谢产物之一。

方法

雄性小鼠（24 天大）通过饮水连续 21 天暴露于 SB。一系列行为测试，主要包括床上用品偏好测试（BP）、性偏好测试（SP）、社交互动测试（SI）、管优势测试（SDT）、强迫游泳测试（FST）、野外测试（OFT）、在 21 天 SB 暴露后的不同时间进行新的物体识别任务 (NOR)。研究了血清三甲胺氧化物 (TMAO) 水平以深入了解潜在机制。

结果

行为结果表明，断奶后 SB 暴露显着降低了低等级小鼠的社会支配地位，并在不影响社会互动的情况下降低了性偏好。SB 暴露还产生短暂的抗焦虑样作用，同时诱导了持久的抑郁样作用而不影响记忆形成。断奶后 SB 暴露增加了小鼠血清 TMAO 水平，尤其是在低级别小鼠中，但在高级别小鼠中降低。

限制

缺乏对潜在机制的了解。

结论

这些发现首次提供了直接证据表明断奶后SB暴露对成年小鼠的社会行为产生长期影响，主要是指性取向、社会支配地位和抑郁样行为，这可能与血清TMAO有关。水平，突出了肠脑相互作用对社会行为的长期潜在影响。