微生物のパターンに対する腸の感覚が 栄養を調節する
Winston W Liu1,2,3,4, Naama Reicher1,3, Emily Alway1,2,3
1Laboratory of Gut Brain Neurobiology, Duke University, Durham, NC, USA.
Nature
|July 23, 2025
まとめ
科学者は神経生物学的感覚と呼ばれる 新しい腸脳の感覚を発見しました この感覚はフラゲリンという 微生物の分子を用いて トール型受容体5 (TLR5) を介して脳に信号を送り 食事の行動を制御します
科学分野:
- 神経科学
- 微生物学
- 胃腸内科
背景:
- 宿主には 寄生した微生物を感知し 反応するメカニズムが必要です
- 腸と脳のコミュニケーションは 宿主の行動や 食事の選択を制御します
- 腸内微生物刺激に対するリアルタイムの感覚メカニズムは以前は知られていなかった.
研究 の 目的:
- 腸内微生物の刺激に 反応する感覚的メカニズムの発見です
- 腸内の微生物の感知に関与する 分子経路を特定する
- この感覚が宿主の行動を 制御する役割を説明する.
主な方法:
- ネズミの腸内ニューロポッド細胞に対するフラゲリンの効果を研究した.
- トール型受容体5 (TLR5) ノックアウトモデルを使用した.
- 試験されたペプチドYY (PYY) の放出とヴァガルノドーズのニューロン活性化.
- フラゲリンに対する反応として 食事の行動と体重増加を評価した.
主要な成果:
- フラゲリンは結腸神経足細胞のTLR5を刺激し,PYYの放出につながります.
- このシグナル伝達経路は 食事の行動を制御し 食事の摂取量を減らします
- ニューロポッド細胞にTLR5が欠けていたマウスは,食物摂取量と体重増加を示した.
- フラゲリン誘発の栄養減少は,免疫反応や微生物群の存在とは無関係です.
結論:
- 神経生物学的感覚という 新しい腸-脳感覚経路が 発見されました
- この感覚は 宿主がフラゲリンのような 微生物の分子パターンに反応して 行動を調整することを可能にします
- 神経生物学的感覚は 腸-脳神経回路を通じて活動し 神経足の細胞と ヴァーガルニューロンが関与しています
関連する概念動画
01:28Microbial Nutrition
304
Organisms exhibit remarkable metabolic diversity, categorized based on how they acquire energy and carbon. These strategies enable survival in various ecological niches and are essential for maintaining energy flow and nutrient cycling within ecosystems.Energy and Carbon SourcesOrganisms are classified as phototrophs or chemotrophs based on energy acquisition. Phototrophs use light as their energy source, while chemotrophs rely on oxidizing chemical compounds. Further differentiation arises...
304
01:30Regulation of Food Intake
472
Short-term regulation of food intake primarily involves neural signals from the gastrointestinal (GI) tract, blood nutrient levels, and GI tract hormones. Communication between the gut and brain via vagal nerve fibers plays a significant role in evaluating the contents of the gut. Clinical studies have shown that protein ingestion produces a more prolonged response in these nerve fibers compared to an equivalent amount of glucose. Additionally, the activation of stretch receptors caused by GI...
472
01:27Microbial Growth Media
256
Microbial growth media are essential tools in microbiology, providing the nutrients and conditions necessary to cultivate and study microorganisms. These media are categorized by their composition, consistency, and functional roles, enabling researchers to investigate microbial physiology, behavior, and interactions.Types and Consistencies of Growth MediaGrowth media can be solid, liquid, or semisolid. Solid media, often agar-based, allow visible colony growth for isolation and enumeration.
256
01:29Methods for Controlling Microbial Growth
496
Microbial growth control refers to various methods employed to inhibit, reduce, or eliminate microorganisms to ensure safety and hygiene across different settings. These methods are categorized based on the target environment and the level of microbial control required.Biocides are versatile agents designed to control microorganisms by either inhibiting their growth or outright killing them. These agents work through various physical, chemical, mechanical, or biological mechanisms. The...
496
01:28Biological Methods for Microbial Control
206
Biological agents offer an effective means of controlling microbial growth by leveraging natural processes like predation, competition, and the secretion of antimicrobial substances.Predatory bacteria such as Bdellovibrio species target and kill pathogens like Salmonella and E. coli. They are widely used in poultry farms to control infections. Myxococcus species help combat plant-pathogenic fungi. These naturally occurring predators serve as eco-friendly alternatives to chemical pesticides and...
206
01:23Stringent Response in E. coli
53
Bacterial growth is closely tied to nutrient availability, with cells proliferating exponentially under favorable conditions and entering a stationary phase when resources become scarce. This transition is mediated by a regulatory mechanism known as the stringent response, which allows bacteria to adapt to nutrient deprivation by modulating gene expression and metabolic activity.During nutrient scarcity, intracellular amino acid levels decline. It results in the accumulation of uncharged tRNAs...
53