Word: miceli
(lookup in dictionary)
(lookup stats)
Dates: during 2000-2009
Sort By: most recent first
(reverse)
...study builds on previous research in mice that suggests that heavy bodies may have a different makeup of gut bugs than thin ones. The gut microbiota of obese mice has been shown to have significantly more of one main type of bacteria called Firmicutes and fewer of another kind called Bacteroidetes (both types populate human guts as well); in normal mice, the distribution is the opposite. Jeffrey Gordon at Washington University in St. Louis, Mo., who conducted the previous research, experimented again with mice for the new paper. This time, however, he and his team used human microbiota to colonize...
Researchers started with mice that were specially bred to be germ-free - with no gut microbiota of their own - and to be able to nurture human gut microbiota. Researchers injected the mice with samples of fresh and frozen human feces, the bacteria from which took hold and colonized in the gut of the mice. If that surprises you, it absolutely stunned the researchers. "We were surprised that so much of the diversity present in human microbial communities could be recaptured in mice," says Gordon, who has been studying gut microbiota for more than five years...
...fact that the human gut flora flourished in the rodents was indeed an experimental coup. Since the mice were genetically engineered to be germ-free, lacking a functioning immune system, the scientists could be certain that any bug colonies that took hold in the mouse guts originated entirely from the human sample, not the mice. Being able to recreate the living human gut environment so faithfully in an animal was a welcome prize. (Read "The Year in Medicine 2008: From...
That diversity and its impact came into plain view when the researchers started experimenting with the rodents' diet. When one group of mice was fed a typical Western diet, high in fat and sugars, they tended to gain weight and grow more Firmicutes gut bacteria and fewer Bacteroidetes. In mice given a low-fat plant-based chow, the distribution of the two groups of bugs flipped and the animals remained lean. It's not clear whether the balance of gut bugs causes weight gain or is a result of it, but the findings suggest that a "gut profile" could potentially...
...leanness profile - a vital-stats sheet of the gut world that would help people understand how their bodies are likely to respond to calories. Beyond that, the possibilities are even more exciting. With more research, Gordon sees potential even for applying to agriculture the knowledge gained from these mice - we could grow more foods that are specifically designed to provide the optimal balance of nutrients and energy for various life stages. "This vast universe of microbes that live on and in us is terra incognita, but it is becoming more cognita every day," he says. "We are beginning to develop...