Institute of Occupational Health and Environmental Health, School of Public Health, Lanzhou University, Lanzhou, 730000, China.
Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining, 810008, Qinghai, People's Republic of China.
Appl Microbiol Biotechnol. 2018 Aug;102(15):6739-6751. doi: 10.1007/s00253-018-9097-z. Epub 2018 Jun 3.
The gut microbiota in mammals plays a key role in host metabolism and adaptation. However, relatively little is known regarding to how the animals adapts to extreme environments through regulating gut microbial diversity and function. Here, we investigated the diet, gut microbiota, short-chain fatty acid (SCFA) profiles, and cellulolytic activity from two common pika (Ochotona spp.) species in China, including Plateau pika (Ochotona curzoniae) from the Qinghai-Tibet Plateau and Daurian pika (Ochotona daurica) from the Inner Mongolia Grassland. Despite a partial diet overlap, Plateau pikas harbored lower diet diversity than Daurian pikas. Some bacteria (e.g., Prevotella and Ruminococcus) associated with fiber degradation were enriched in Plateau pikas. They harbored higher gut microbial diversity, total SCFA concentration, and cellulolytic activity than Daurian pikas. Interestingly, cellulolytic activity was positively correlated with the gut microbial diversity and SCFAs. Gut microbial communities and SCFA profiles were segregated structurally between host species. PICRUSt metagenome predictions demonstrated that microbial genes involved in carbohydrate metabolism and energy metabolism were overrepresented in the gut microbiota of Plateau pikas. Our results demonstrate that Plateau pikas harbor a stronger fermenting ability for the plant-based diet than Daurian pikas via gut microbial fermentation. The enhanced ability for utilization of plant-based diets in Plateau pikas may be partly a kind of microbiota adaptation for more energy requirements in cold and hypoxic high-altitude environments.
哺乳动物的肠道微生物群在宿主代谢和适应中起着关键作用。然而，对于动物如何通过调节肠道微生物多样性和功能来适应极端环境，我们知之甚少。在这里，我们研究了来自中国两种常见的高原鼠兔（Ochotona curzoniae）和达乌尔鼠兔（Ochotona daurica）的饮食、肠道微生物群、短链脂肪酸（SCFA）谱和纤维素酶活性。尽管有部分饮食重叠，但高原鼠兔的饮食多样性低于达乌尔鼠兔。一些与纤维降解有关的细菌（如Prevotella 和 Ruminococcus）在高原鼠兔中富集。它们的肠道微生物多样性、总 SCFA 浓度和纤维素酶活性均高于达乌尔鼠兔。有趣的是，纤维素酶活性与肠道微生物多样性和 SCFA 呈正相关。肠道微生物群落和 SCFA 谱在宿主物种之间结构上存在差异。PICRUSt 宏基因组预测表明，参与碳水化合物代谢和能量代谢的微生物基因在高原鼠兔的肠道微生物群中过度表达。我们的研究结果表明，高原鼠兔通过肠道微生物发酵，对植物性饮食具有比达乌尔鼠兔更强的发酵能力。高原鼠兔对植物性饮食的利用能力增强，可能部分是为了在高寒缺氧的高海拔环境中满足更多的能量需求而进行的一种微生物适应。
