把肠道细菌做成特效药

皇后

http://www.popsci.com/gut-bacteria-medicine
Scientists want to turn our gut bacteria into medicine

The bacteria inside our guts—which collectively make up the so-called gutmicrobiome—are incredibly diverse, with countless species and strains. But they also differ depending on the individual, with one person’s microbiome having little to do with another’s. And scientists have found that these differences can relate to our health. A person with diabetes is more likely to have a certain suite of microbes than a person without diabetes, for example. But the mechanisms of this bacterial influence are still pretty mysterious.

In a paper published Wednesday in the journal Nature, scientists took a step towards figuring that out. They found that a molecule produced by certain bacteria can interact with protein receptors in mice—receptors also found in humans—and ultimately improve the rodent’s glucose regulation. The results could help researchers understand how bacteria keep us healthy, and what changes on a bacterial level when we fall prey to disease. And in the future, having that knowledge could allow us to harness naturally occurring microbes to actually treat illness.

“We knew that bugs make molecules that enable them to communicate. And that these molecules target receptors in human cells. Bugs in us are probably making molecules, too. Those molecules might have some effects on us,” says lead author Sean Brady, a microbiologist at the Rockefeller University.

Over the past couple of years, Brady and his team have scoured stool samples to analyze the DNA of microbes living within. All this digging revealed a signaling molecule in the bacteria known as N-acyl amides. In humans, these molecules are involved in a variety of different signaling pathways. For instance, they bind to a group of proteins found on the outside surface of cells known as GPCR. Once bound, they tell the cell to perform certain functions, like release neurotransmitters or other proteins. In essence, they help the body regulate itself.

The researchers zeroed in on the interaction of N-acyl amides with GPR119, which helps control blood sugar regulation in mice. They gave one group of subjects a strain of bacteria containing N-acyl, and left the others without it. They found that the clan of mice that received N-acyl amides had significantly better glucose metabolism than those who didn’t have them. In other words, the mice that got the special bugs were better able to break down and use the energy found in glucose, allowing them to send it to cells and tissues so that it could fuel their bodily functions.

So what does this all mean for humans? We already understand that microbes can have an effect on our health, but how they actually influence us is unclear. If we can identify interactions like the one Brady and his team found—and show that they also occur in humans—we can figure out how to use bacteria as medicine. In theory, such a connection between bacteria and signaling molecules could help regulate blood sugar, control weight, or even prevent autoimmune disease flare-ups.

But this goal is still some years away. For now, all we really know is that a greater variety of gut microbes seems to be beneficial. And the best way to improve gut diversity is to eat a variety of food, including a lot of fruits and vegetables.And fiber. A ton of fiber.

http://jandan.net/2017/09/03/bacteria-medicine.html

肠道里的微生物能让你保持健康，科学家们终于明白了它们是怎么做到的。

在我们的肠道内，分布着各种各样的肠道微生物。而具体什么品种是取决于个人，一个人的肠道菌群和其他人是不一样的。科学家们还发现，这些差异可能与我们的健康息息相关。例如，患有糖尿病的人比没有糖尿病的人更容易携带上某种微生物。目前为止，科学家还没有发现这种细菌是如何对人造成影响的。

于星期三发表在《自然》杂志上的一篇论文中，科学家们取得了一些进展。他们发现，某些细菌产生的一种分子可以与小鼠体内的蛋白受体相互作用(这种受体在人体内也发现了)，并且最终能改善啮齿类动物的葡萄糖调节水平。这些结果可以帮助研究人员了解细菌是如何使我们保持健康的；也让我们知道，当我们生病时，细菌水平发生了什么变化。如果在未来我们掌握了这些知识，就可以利用自然产生的微生物来治疗疾病。

“病菌能产生促使他们自身交流的分子是不争的事实。”这些分子在人体细胞中目的转向了受体。我们人体内的病菌也可能制造分子，并且这些分子可能会对我们有一些影响，”第一作者、来自洛克菲勒大学的微生物学家Brady如是说。

过去的几年中，为分析其中微生物的DNA，Brady和他的团队对粪便样本进行了冲洗。他们在菌体内发现了信号分子酰基酰胺。而在人体中，这些分子构成了各种不同的信号通路。例如，它们与一组细胞表面发现的蛋白质——G蛋白偶联受体相结合。一旦绑定，他们便告诉细胞该执行某些功能，如释放神经递质或其他蛋白质。从本质上说，它们是有助于身体自我调节的。

研究人员把注意力集中在酰基酰胺与GPR119的相互作用上，因为这有助于小白鼠控制血糖调节。他们给其中一组放入含有N-酰基的细菌菌株，而其他对照组不放。结果发现拥有酰基酰胺的小白鼠比没有的小白鼠拥有更强的葡萄糖代谢能力。换句话说，获得这种特殊菌体的老鼠能够更好地分解并利用葡萄糖中的能量，并将其送到细胞和组织中，从而为身体提供能量。

那么这一切对人类来说，意味着什么？我们已经明白微生物对我们的健康会造成影响，但它们到底如何影响我们，还并不清楚。如果我们能够识别像Brady和他的团队发现的那种相互作用，并让它们也发生在人类身上，我们就能找到如何让细菌变为药物的方法了。理论上来说，细菌和信号分子之间的这种联系是有助于调节血糖、控制体重的，甚至还能防止自身免疫疾病。

但是距离实现这个目标还有好几年的时间。就目前来说，肠道微生物种类繁多似乎是有益的。增强肠道多样性的最好方法是吃各种各样的食物，包括大量的水果、蔬菜以及纤维——许许多多的纤维！

weken

祝福小家伙平安健康。

皇后

weken 发表于 2017-10-12 17:05
祝福小家伙平安健康。

哪个小家伙健康