Monday, 4 April 2011

All hail the gut bacteria

'Flash, ah-ahh'. Flash Gordon. You remember him, and that fantastic film in 1980 with the soundtrack by Queen. Max von Sydow played Ming the Merciless who ruled Mongo with a iron fist. 'All hail Ming, Ruler of the Universe' was the chant from his (dis)loyal subjects. Well, Ming might well have been Ruler of the Cosmos, but us humans may very well bow down to another Ruler - or should I say a couple of trillion Rulers - our endogenous gut bacteria.

Despite my previous posts examining a possible relationship between some cases of autism spectrum conditions and 'abnormal' gut bacteria, this post is a little different. Different because it is not looking at gut bacteria in relation to autism per se, but rather some wider research.

Before I start, I want to acknowledge a few sources of information including Emily Deans over at Evolutionary Psychiatry, Maff at the Environmental Illness Resource and the Neurophilosophy blog (I don't want any charges of plagiarism levelled against me).

My attention was turned to two papers published recently on a possible bi-directional relationship between gut bacteria and behaviour in mice. By bi-directional, I mean that gut bacteria could influence behaviour and behaviour could influence gut bacteria. OK I hear you cry, fine if you are a mouse - and you would be absolutely right. But remember that mice are used to build a variety of different models of human functioning including that related to autism (see special edition of the Autism Research journal on mouse models).

Both the papers highlighted have generated quite a bit of discussion on their various implications.
The paper suggesting that behaviour (in this case, stress) can affect gut bacterial populations implies a few things: (a) gut bacterial populations are dynamic and responsive to our psychology and/or behaviour as well as more physiologically-determined variables such as medication or diet, (b) where gastrointestinal conditions are present and potentially tied into gut bacteria (IBS for example), the mechanism for psychosocial stress impinging on symptoms may well be tied in. This last point in particular may have some relevance for specific cases of autism spectrum conditions where stress and arousal seem to be common. Think also to my recent post covering probably the most undesirable therapy ever invented, fecal transplantation and the implications of a comment posted in jest on the EP blog "..if you ever have a fecal transplant, make sure it is from a slender, non-asthmatic, happy person!".

The other paper detailing the effect of gut bacteria (or lack of it) on behaviour seems to tie in with the growing interest in such a relationship related to autism. Remember that study from Richard Sandler and colleagues from 2000 where short-term administration of a powerful antimicrobial acting on gut bacteria (I assume!) led to some short-term positive behavioural changes in children with autism?

As per the ethos of this blog I have tried to tie the work back to autism, but really these papers potentially show some applicability to lots of different areas. ME/CFS perhaps? How about what happens when we try and change/affect our gut bacterial populations? What happens to behaviour?

This paper was published a few years back and tried just that. Using a double-blind, placebo-controlled methodology, the authors looked at what happened to anxiety symptoms in participants with CFS when a probiotic preparation was taken. The results: a rise in the 'good' bacteria (aerobic predominantly) and a decrease in anxiety symptoms when taking the probiotic over the placebo. Let's be straight though. I am not saying that such an intervention will help everyone with every condition. But all these papers tell us that perhaps we should be looking at our gut bacterial populations a little more closely from a research perspective.

All hail the gut bacteria, ruler of OUR Cosmos!