肠道细菌人造甜味剂与葡萄糖不耐症.docx

Artificial sweeteners - promoted as aids to weight loss and diabetes1 prevention - could actually hasten the development of glucose2 intolerance and metabolic3 disease, and they do so in a surprising way: by changing the composition and function of the gut4 microbiota - the substantial population of bacteria residing in our intestines5. These findings, the results of experiments in mice and humans, were published September 17 in Nature. Dr. Eran Elinav of the Weizmann Institute of Sciences Department of Immunology, who led this research together with Prof. Eran Segal of the Department of Computer Science and Applied6 Mathematics, says that the widespread use of artificial sweeteners in drinks and food, among other things, may be contributing to the obesity7 and diabetes epidemic8 that is sweeping9 much of the world. For years, researchers have been puzzling over the fact that non-caloric artificial sweeteners do not seem to assist in weight loss, with some studies suggesting that they may even have an opposite effect. Graduate student Jotham Suez in Dr. Elinavs lab, who led the study, collaborated10 with lab member Gili Zilberman-Shapira and graduate students Tal Korem and David Zeevi in Prof. Segals lab to discover that artificial sweeteners, even though they do not contain sugar, nonetheless have a direct effect on the bodys ability to utilize11 glucose. Glucose intolerance - generally thought to occur when the body cannot cope with large amounts of sugar in the diet - is the first step on the path to metabolic syndrome12 and adult-onset diabetes. The scientists gave mice water laced with the three most commonly used artificial sweeteners, in amounts equivalent to those permitted by the U.S. Food and Drug Administration (FDA). These mice developed glucose intolerance, as compared to mice that drank water, or even sugar water. Repeating the experiment with different types of mice and different doses of the artificial sweeteners produced the same results - these substances were somehow inducing glucose intolerance. Next, the researchers investigated a hypothesis that the gut microbiota are involved in this phenomenon. They thought the bacteria might do this by reacting to new substances like artificial sweeteners, which the body itself may not recognize as food. Indeed, artificial sweeteners are not absorbed in the gastrointestinal tract13, but in passing through they encounter trillions of the bacteria in the gut microbiota. The researchers treated mice with antibiotics14 to eradicate15 many of their gut bacteria; this resulted in a full reversal of the artificial sweeteners effects on glucose metabolism16. Next, they transferred the microbiota from mice that consumed artificial sweeteners to germ-free, or sterile17, mice - resulting in a complete transmission of the glucose intolerance into the recipient18 mice. This, in itself, was conclusive19 proof that changes to the gut bacteria are directly responsible for the harmful effects to their hosts metabolism. The group even found that incubating the microbiota outside the body, together with artificial sweeteners, was sufficient to induce glucose intolerance in the sterile mice. A detailed20 characterization of the microbiota in these mice revealed profound changes to their bacterial21 populations, including new microbial functions that are known to infer a propensity22 to obesity, diabetes, and complications of these problems in both mice and humans.词汇表：1 diabetes n.糖尿病参考例句：In case of diabetes, physicians advise against the use of sugar.对于糖尿病患者，医生告诫他们不要吃糖。Diabetes is caused by a fault in the insulin production of the body.糖尿病是由体內胰岛素分泌失调引起的。2 glucose n.葡萄糖参考例句：I gave him an extra dose of glucose to pep him up.我给他多注射了一剂葡萄糖以增强他的活力。The doctor injected glucose into his patients veins.医生将葡萄糖注入病人的静脉。3 metabolic adj.新陈代谢的参考例句：Impressive metabolic alternations have been undergone during embryogenesis.在胚胎发生期间经历了深刻的代谢变化。A number of intoxicants are associated with metabolic acidosis.许多毒性物质可引起代谢性酸中毒。4 gut n.pl.胆量；内脏；adj.本能的；vt.取出内脏参考例句：It is not always necessary to gut the fish prior to freezing.冷冻鱼之前并不总是需要先把内脏掏空。My immediate gut feeling was to refuse.我本能的直接反应是拒绝。5 intestines n.肠( intestine的名词复数 )参考例句：Perhaps the most serious problems occur in the stomach and intestines. 最严重的问题或许出现在胃和肠里。 来自辞典例句The traps of carnivorous plants function a little like the stomachs and small intestines of animals. 食肉植物的捕蝇器起着动物的胃和小肠的作用。 来自辞典例句6 applied adj.应用的；v.应用，适用参考例句：She plans to take a course in applied linguistics.她打算学习应用语言学课程。This cream is best applied to the face at night.这种乳霜最好晚上擦脸用。7 obesity n.肥胖，肥大参考例句：One effect of overeating may be obesity.吃得过多能导致肥胖。Sugar and fat can more easily lead to obesity than some other foods.糖和脂肪比其他食物更容易导致肥胖。8 epidemic n.流行病；盛行；adj.流行性的，流传极广的参考例句：That kind of epidemic disease has long been stamped out.那种传染病早已绝迹。The authorities tried to localise the epidemic.当局试图把流行病限制在局部范围。9 sweeping adj.范围广大的，一扫无遗的参考例句：The citizens voted for sweeping reforms.公民投票支持全面的改革。Can you hear the wind sweeping through the branches?你能听到风掠过树枝的声音吗？10 collaborated 合作( collaborate的过去式和过去分词 )； 勾结叛国参考例句：We have collaborated on many projects over the years. 这些年来我们合作搞了许多项目。We have collaborated closely with the university on this project. 我们与大学在这个专案上紧密合作。11 utilize vt.使用，利用参考例句：The cook will utilize the leftover ham bone to make soup.厨师要用吃剩的猪腿骨做汤。You must utilize all available resources.你必须利用一切可以得到的资源。12 syndrome n.综合病症；并存特性参考例句：The Institute says that an unidentified virus is to blame for the syndrome. 该研究所表示,引起这种综合症的是一种尚未确认的病毒。Results indicated that 11 fetuses had Down syndrome. 结果表明有11个胎儿患有唐氏综合征。13 tract n.传单，小册子，大片(土地或森林)参考例句：He owns a large tract of forest.他拥有一大片森林。He wrote a tract on this subject.他曾对此写了一篇短文。14 antibiotics n.（用作复数）抗生素；（用作单数）抗生物质的研究；抗生素，抗菌素( antibiotic的名词复数 )参考例句：the discovery of antibiotics in the 20th century 20世纪抗生素的发现The doctor gave me a prescription for antibiotics. 医生给我开了抗生素。15 eradicate v.根除，消灭，杜绝参考例句：These insects are very difficult to eradicate.这些昆虫很难根除。They are already battling to eradicate illnesses such as malaria and tetanus.他们已经在努力消灭疟疾、破伤风等疾病。16 metabolism n.新陈代谢参考例句：After years of dieting,Carols metabolism was completely out of whack.经过数年的节食，卡罗尔的新陈代谢完全紊乱了。All living matter undergoes a process of metabolism.生物都有新陈代谢。17 sterile adj.不毛的，不孕的，无菌的，枯燥的，贫瘠的参考例句：This top fits over the bottle and keeps the teat sterile.这个盖子严实地盖在奶瓶上，保持奶嘴无菌。The farmers turned the sterile land into high fields.农民们把不毛之地变成了高产田。18 recipient a.接受的,感受性强的 n.接受者,感受者,容器参考例句：Please check that you have a valid email certificate for each recipient. 请检查是否对每个接收者都有有效的电子邮件证书。Colombia is the biggest U . S aid recipient in La