Our Second Brain

We always thought that we are the brain and the brain is us; but we’ll have to change that conception, because that very brain is continuously being manipulated by that second brain — that doughy, yellowish organ in our intestine-specially in the large colon

Just visualize ourselves as a cylindrical tube: a cylindrical wall with two openings. What is around that tube – air? space? There is much more: an infinite ocean of microbes – bacteria and viruses; in fact, the tube cannot escape that ocean, unless it goes into deep intergalactic space .The truth is that those microbes existed long before the tube which can be looked upon as the intruder. From another viewpoint, it is itself a by-product of that ocean of microbes, having been fashioned over millions or billions of years.

Of course, the malefic, toxic, virulent microbes did not want that tube. But one good day they realized that they could allow it to come into existence and use it as a host to propagate themselves — as parasites – and play the evolutionary card. In the process some milder, benevolent microbes also competed to get a place under the sun: they became symbiotic, most probably fashioning the very cells of that tube; so much so it is said that the gene of a placenta is the exact copy of the genome of a virus! And in mammals the tube got cleverer still: did the docile microbes facilitate a womb where the foetus would remain sterile, far from virulent microbes, until it is mature enough to be delivered out to face that ocean of bugs? Perhaps.

And the tube developed all sorts of processes to filter out the bad bacteria and viruses; the outer covering of the tube, the skin, is a wonderful organ. Without it the tube would die a slow death within days; the upper opening otherwise known as the mouth is said to be the ‘dirtiest’ of the tube. Rightly so, because it is exposed to the atmosphere. The tonsils found lower down the mouth would play a definite role, filtering the bugs and eliciting all sorts of immune cells and system to prevent the destruction of the tube and internal organs.

No more yuck

Yet lower down still, inside the tube between the upper and lower openings there is no skin, but the tube survives. The record of millions of years of adaptation is written inside there. All sort of juices and acids have been secreted to control some of the microbes and facilitate food digestion. Both hunger and the pleasure principle associated with food are manipulated by the gut and its hormones and neurotransmitters they secrete. But the wonder of all, discovered in the last decade, is that what has been looked upon with disgust as waste material and faecal matter must now be looked upon as an organ by itself! All the microbes embedded therein, known as the microbiome, seem to be the master of the tube; they literally patrol the gut. They outnumber the cells of the body of the tube, and even weigh more than the brain. New facts are emerging, putting our intelligence to shame for having looked down upon these microbes with disdain and disgust.

Do they control the fat cells of the tube; do they direct the hunger of the host; do they have a say on the allergy suffered by that tube? Yes. Do they control the integrity and health of the inner lining of that tube? Yes. Could they, by their absence or overpopulation, cause all sorts of disease, maybe cancers, to erupt in the body? Yes. Do they have a say in the immune potentiality of the body? Yes. Old patients having continuous high temperature, not responding to any treatment do recover miraculously when faecal material from their children are injected into their gut! And many with inflammatory bowel disease (colitis), suffering from constant diarrhea and bloody motion, are suddenly being cured by this faecal transplant. Even some obese diabetic patients have benefited by this unorthodox prescription. Cases of Parkinsonism or autism have responded positively to such manipulation of the intestinal flora. But as these are isolated cases, a lot of scientific work remains to be done to assess these benefits.

This microbiome is very sensitive to an excess of antibiotics, which leads to a change in internal flora, sometimes triggering more serious health problems. Think of the fat chicken having been fed all sorts of antibiotics — do those antibiotics survive, come into our gut and influence negatively our bacteria, and make us prone to obesity? Or the 70% of all USA antibiotics production being given to farm animals, for the sake of business.

Scientists had known for long that these microbes produce a lot of vitamins and other elements for the host, but that they should have such a potent, far-reaching influence on the human organism and its brain was never thought of. They produce neurotransmitters like serotonin from tryptophan (found mostly in lettuce, banana and eggs), which when converted to melatonin will influence our sleep; even our memory, psychological well- being and mood depend partly on that microbiome in our gut. It even influences our craze for fatty and sugary sweetmeats by sending all sorts of impulses to the brain; they ‘tell’ us what to eat – and send us to the fridge at night when the spouse is snoring. But more important are the variety and relative proportions of bugs found there: they will finally determine even our longevity.

We always thought that we are the brain and the brain is us; but we’ll have to change that conception, because that very brain is continuously being manipulated by that second brain — that doughy, yellowish organ in our intestine-specially in the large colon. They somehow get access to some of our genes and tease them into different directions; could they be responsible for so many of our physical problems? Perhaps. We’ll have to reinvent, yet again, our concept of holistic thinking.

Maternal Role

Mothers play a significant role in passing her microbes to her children; the close association between them will ensure that these bugs will colonize the gut of the newborn and set a trend of life, of thinking and behaviour almost similar to the mater. That’s where the immune system will build up and protect the child. Hence the importance of maternal milk and close contact between child and mother. And those born by caesarean? Not coming through the natural passage, they will get less of the mother’s flora and fauna (from the vagina) and will be prone to develop some allergy later in life; so much so some people are practising ‘vaginal lavage’ on to the new born after a caesarean. But the benefit is yet to be confirmed. But we could start doing away with unnecessary caesareans and antibiotics, so as to promote the intestinal microbiome of the new born.

If we stay together for 4 hours or more in a social gathering, then we start sharing our microbes from every part of our body! That’s why we need well aerated, ventilated surroundings during meetings. But the upshot of such sociability, in collective sports or prayer, is that the more social we are the longer we live, by exchanging bacteria! We sort of not only stabilize our psychology, but we increase our chances of improving our health.

We were most nervous and irritated when our children used to put their toys in their mouth; now the teaching is – let them do it, it is all for the good! One young colleague told us that every time he returns from a party he has a saline gargle so as to avoid catching a sore throat or a cold. Perhaps he will miss out on his immunity as his priority is short term — to be fit for work the following morning.

Yes, we have been very proud of our free will and our cerebrum; but we are realizing that we have a second brain – in our tummy. The vision is that one day our health professionals will analyse our stool, and do bacterial replacement therapy to cure, hopefully, most of our diseases. Already biotechnologically modified bacteria are being used to chase away such virulent villains like pseudomonas aeruginosa from our body. The same process would be used to favour the commensal or friendly bacteria. There is talk of prebiotics, the chemicals in our food, and probiotics, the friendly varied lactobacilli necessary for our health, not forgetting the fibres in our vegetables and fruits.

But as with all human concepts, there is always the other side of the coin – already there is an abuse of this new treatment and approach to our gut! Our well-being depends on so many factors, genetic and environmental, and our microbiome is one of them. It is time we recognize it, and treat our gut, its contents, its flora and bacteria with greater understanding. We cannot change our genes or our brain but we can manipulate our intestinal flora so as to influence positively our first brain and our life.

The tummy, between that upper and lower openings of the tube, harbours a second brain…

* Published in print edition on 13 May 2016