Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen O, Denmark.
Novo Nordisk Foundation Center for Stem Cell Research, Faculty of Health and Medical Science, University of Copenhagen, Copenhagen N, Denmark.
Wiley Interdiscip Rev Dev Biol. 2020 Nov;9(6):e378. doi: 10.1002/wdev.378. Epub 2020 Mar 16.
Multicellular organisms have evolved organs and tissues with highly specialized tasks. For instance, nutrients are assimilated by the gut, sensed, processed, stored, and released by adipose tissues and liver to provide energy consumed by peripheral organ activities. The function of each organ is modified by local clues and systemic signals derived from other organs to ensure a coordinated response accommodating the physiological needs of the organism. The intestine, which represents one of the largest interfaces between the internal and external environment, plays a key role in sensing and relaying environmental inputs such as nutrients and microbial derivatives to other organs to produce systemic responses. In turn, gut physiology and immunity are regulated by multiple signals emanating from other organs including the brain and the adipose tissues. In this review, we highlight physiological processes where the gut serves as a key organ in coupling systemic signals or environmental cues with organism growth, metabolism, immune activity, aging, or behavior. Robust strategies involving intraorgan and interorgan signaling pathways have evolved to preserve gut size in homeostatic conditions and restrict growth during damage-induced regenerative phases. Here we review some of the mechanisms that maintain gut size homeostasis and point out known examples of homeostasis-breaking events that promote gut plasticity to accommodate changes in the external or internal environment. This article is categorized under: Adult Stem Cells, Tissue Renewal, and Regeneration > Tissue Stem Cells and Niches Adult Stem Cells, Tissue Renewal, and Regeneration > Environmental Control of Stem Cells Adult Stem Cells, Tissue Renewal, and Regeneration > Regeneration.
多细胞生物进化出具有高度专门化任务的器官和组织。例如，肠道吸收营养物质，脂肪组织和肝脏感知、处理、储存和释放营养物质，为外周器官活动提供消耗的能量。每个器官的功能都通过来自其他器官的局部线索和系统信号进行修饰，以确保协调的反应，适应生物体的生理需求。肠道是内部和外部环境之间最大的接口之一，它在感知和传递环境输入方面发挥着关键作用，例如营养物质和微生物衍生物，以产生全身反应。反过来，肠道生理学和免疫功能又受到来自其他器官（包括大脑和脂肪组织）的多种信号的调节。在这篇综述中，我们强调了肠道作为将系统信号或环境线索与生物体生长、代谢、免疫活性、衰老或行为联系起来的关键器官的生理过程。涉及器官内和器官间信号通路的强大策略已经进化，以在稳态条件下保持肠道大小，并在损伤诱导的再生阶段限制生长。本文综述了维持肠道大小稳态的一些机制，并指出了一些已知的打破稳态的事件，这些事件促进了肠道可塑性，以适应外部或内部环境的变化。本文属于以下分类： 成体干细胞、组织更新和再生 > 组织干细胞和龛 成体干细胞、组织更新和再生 > 干细胞的环境控制 成体干细胞、组织更新和再生 > 再生。
