That Feeling in Your Gut? Intestinal Flora

"As animals ourselves, we have more than 1000 different kinds of microorganisms living in our guts ...._abcnet

Intestinal microbes can determine the quality of your life, and your perception of it. Your guts are the repository of the majority of your microbial complement. Life without "normal flora" would be a different animal.

Professor Petterson and his colleagues bred a number of mice under normal and germ-free conditions. In stantardised tests of activity, the germ-free mice explored more of an "open-field activity box", rearing up on their hind legs more often, and showed less of the signs associated with anxiety.

In studies of the animals' brains, they showed higher levels of a number of hormones, and even differences in the expression of over 170 genes.

The result does not paint a clear picture of whether the development of the germ-free mice is specifically "better" or "worse" for the animals, Professor Pettersson explained, but is a "very, very interesting" first demonstration that the bugs can have such profound effects even within the brain.

It follows a long line of studies that suggest the bugs are far more involved in mammalian function than just in their digestion. _BBC

Very interesting. The germ-free animals lived longer and seemed more curious, but they were very fragile to stress and various types of injury, compared to animals with normal bacterial and skin flora.

If we are to swim in a sea of bacteria -- as it seems we are destined to do -- it is best that our bacterial partners be sympatico with us. If we wish to avoid chronic intestinal inflammation, fatty liver, obesity, and a wide range of other pathologies and malaise, we need to pay attention to our bacterial friends.

Gut inflammation allows the intrusion of large numbers of various protein intruders which are better kept out of the blood and lymph systems. Yes, we can eat more yoghurt, or take probiotic capsules or powders. Not a bad idea, actually. We may even want to begin to gene-engineer our probiotics for maximal benefit against these ailments. In situations of grave extremis, we may be forced into fecal transplants -- as a last resort.

Al Fin clinical and synth-bio microbiologists recommend genetically engineered probiotics out of all the choices mentioned above: from germ-free environments to fecal transplants. But different situations call for different remedies. Consider each case individually.

Researchers looked in detail at the molecular effects of the engineered bacteria and found that the production of regulatory immune cells, rather than of inflammatory immune cells, was enhanced. "When we treat mice with the new strain, we see more accumulation and generation of cells that produce regulatory proteins, which lure and generate regulatory T cells," says Mohamadzadeh. The regulatory T cells, a type of immune cell, counteract the effects of harmful immune cells that attack the cells lining the gut, he says.

...Mohamadzadeh's team is also exploring engineered probiotics as a treatment for colon cancer. In preliminary studies in mice designed to mimic colon cancer, treatment with the modified bacteria reduced the number of polyps the animals developed by 90 percent. "We observed an average of just three small polyps in treated mice, compared to about 35 to 50," he says.

He adds that the bacteria's ability to reduce inflammation isn't limited to the gut; the regulatory cells migrate throughout the body. That means the microbes may also be able to help treat other diseases linked to inflammation, such as rheumatoid arthritis and psoriasis. _TechnologyReview

Of course, once you start introducing targeted gene-engineered microbes into the gut, the possibilities for treatments and specific optimisations multiply rapidly.

You may be aware that peptic ulcers and gastric cancer are tied to a gastric microbe, helicobacter pylori. The development of counter-bacteria to H. Pylori would allow simple, food-assisted treatment for a number of illnesses specific to that microbe.

The same arguments could be applied to skin bacteria and other parts of the body where normal bacterial flora reside. There are plenty of diseases of multiple systems which are caused or made worse by absent or insufficient symbiotic bacteria.

But once we start applying, ingesting, and inserting engineered microbes for treatment and prophylaxis, we are likely to begin thinking about optimisation. Why take nutritional supplements, for example, when microbes can produce the needed substance just as well? The same applies to particular medications, enzymes, or hormones. And so on...

Now go eat your yoghurt.