Khakisahneh Saeid, Zhang Xue-Ying, Nouri Zahra, Wang De-Hua
State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China.
mSystems. 2020 Oct 20;5(5):e00514-20. doi: 10.1128/mSystems.00514-20.
Ambient temperature ( ) is an important factor in shaping phenotypic plasticity. Plasticity is generally beneficial for animals in adapting to their environments. Gut microbiota are crucial in regulating host physiological and behavioral processes. However, whether the gut microbiota play a role in regulating host phenotypic plasticity under the conditions of repeated fluctuations in environmental factors has rarely been examined. We used intermittent acclimations to test the hypothesis that the plasticity of gut microbiota confers on the host a metabolic adaptation to fluctuations. Mongolian gerbils () were acclimated to intermittent 5°C to 23°C, 37°C to 23°C or 23°C to 23°C conditions for 3 cycles (totally 3 months). Intermittent acclimations induced variations in resting metabolic rate (RMR), serum thyroid hormones, and core body temperature ( ). We further identified that the β-diversity of the microbial community varied with and showed diverse responses during the 3 cycles. Some specific bacteria were more sensitive to and were associated with host dynamic metabolic plasticity during acclimations. In addition, depletion of gut microbiota in antibiotic-treated gerbils impaired metabolic plasticity, particularly at low , whereas supplementation with propionate as an energy resource improved the inhibited thermogenic capacity and increased the survival rate in the cold. These findings demonstrate that both gut microbiota and their host were more adaptive after repeated acclimations, and dynamic gut microbiota and their metabolites may confer host plasticity in thermoregulation in response to fluctuations. It also implies that low is a crucial cue in driving symbiosis between mammals and their gut microbiota during evolution. Whether gut microbiota play a role in regulating host phenotypic plasticity in small mammals living in seasonal environments has rarely been examined. The present study, through an intermittent temperature acclimation model, indicates that both gut microbiota and their host were more adaptive after repeated acclimations. It also demonstrates that dynamic gut microbiota confer host plasticity in thermoregulation in response to intermittent temperature fluctuations. Furthermore, low temperature seems to be a crucial cue in driving the symbiosis between mammals and their gut microbiota during evolution.
环境温度（ ）是塑造表型可塑性的一个重要因素。可塑性通常有利于动物适应其环境。肠道微生物群在调节宿主生理和行为过程中起着关键作用。然而，在环境因素反复波动的条件下，肠道微生物群是否在调节宿主表型可塑性方面发挥作用，这一点很少被研究。我们采用间歇性驯化来检验肠道微生物群的可塑性赋予宿主对波动的代谢适应性这一假设。将蒙古沙鼠（ ）分别置于5°C至23°C、37°C至23°C或23°C至23°C的间歇性条件下驯化3个周期（共3个月）。间歇性驯化诱导了静息代谢率（RMR）、血清甲状腺激素和核心体温（ ）的变化。我们进一步发现，微生物群落的β多样性随 而变化，并在3个周期中表现出不同的反应。一些特定细菌对 更敏感，并与驯化期间宿主的动态代谢可塑性相关。此外，抗生素处理的沙鼠肠道微生物群的耗竭损害了代谢可塑性，尤其是在低温时，而补充丙酸盐作为能量来源可改善受抑制的产热能力并提高在寒冷环境中的存活率。这些发现表明，经过反复驯化后，肠道微生物群及其宿主都具有更强的适应性，动态的肠道微生物群及其代谢产物可能赋予宿主在体温调节方面的可塑性以应对 的波动。这也意味着低温是在进化过程中驱动哺乳动物与其肠道微生物群共生的关键线索。在生活于季节性环境中的小型哺乳动物中，肠道微生物群是否在调节宿主表型可塑性方面发挥作用很少被研究。本研究通过间歇性温度驯化模型表明，经过反复驯化后，肠道微生物群及其宿主都具有更强的适应性。它还表明，动态的肠道微生物群赋予宿主在体温调节方面的可塑性以应对间歇性温度波动。此外，低温似乎是在进化过程中驱动哺乳动物与其肠道微生物群共生的关键线索。
