Probiotic mix effective for IBS?

We are already starting to appreciate just how (a) complex and (b) important our gut microbiota are to health and wellbeing outside of the more traditional duties of food digestion and making the odd nutrient or two. Those trillions of beasties which call us home seem to be cropping up everywhere these days in research terms, based on investigations as diverse as obesity (see here) and autoimmunity (see here) even to the point of speculation about involvement in psychological development (see here) (mice, not humans, mice... so far). That and the fact that stability seems to be a good word to describe their bacterial lives* (assuming that you don't swallow a grenade).

That being said, the involvement of gut bacteria whether alone or as part of the triad of gut involvement - gut bacteria, gut permeability and mucosal / systemtic immunity** - in relation to gastrointestinal (GI) illness and/or dysfunction should not get too lost in the dialogue. Indeed, how modification of gut bacteria, whether through diet, medicine or other means (yes, yuck factor 10) remains a real point of interest when it comes to GI conditions.

With that in mind I turn today to the paper by Yoon and colleagues*** who following quite a rigourous trial (double-blind, placebo-controlled) suggested that a mix of probiotics given over 4 weeks might be able to do some positive things to the symptoms of formally diagnosed irritable bowel syndrome (IBS). The "multi-species" mix included various species and strains: Bifidobacterium longum, Bifidobacterium bifidum, Bifidobacterium lactis, Lactobacillus acidophilus, Lactobacillus rhamnosus, and Streptococcus thermophilus. The authors reported that more of those in receipt of the probiotic mix reported greater relief from their IBS symptoms over and above placebo, and when looking at fecal microflora, there were accompanying changes too as a result of the mix. Interestingly even in the placebo group there were some bacterial changes to be had (mind over matter?).

I know that the Yoon paper is not necessarily new news when it comes to probiotics and IBS (see here) but what this paper does add is its suggestion that rather than thinking too narrow about specific bacteria and species affecting specific conditions, we should perhaps be taking a more broad perspective and realising that the whole is greater than the sum of its parts when it comes to the intricate connections between our various passengers residing in the gut.

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* Faith JJ. et al. The long-term stability of the human gut microbiota. Science. 2013 Jul 5;341(6141):1237439. doi: 10.1126/science.1237439.

** Groeger D. et al. Bifidobacterium infantis 35624 modulates host inflammatory processes beyond the gut. Gut Microbes. 2013 Jun 21;4(4).

*** Yoon JS. et al. Effect of multi-species probiotics on irritable bowel syndrome: a randomized, double-blind, placebo-controlled trial. J Gastroenterol Hepatol. 2013 Jul 5. doi: 10.1111/jgh.12322.

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Coeliac disease as a model of autoimmunity

A very short post primarily to link to a recent paper by Kumar and colleagues* (full-text, at least for the moment).

The paper is a sort of 'all you ever wanted to know about coeliac / celiac disease but were afraid to ask' type piece and jolly informative in terms of what we think we know so far about the condition regarding genes, heritability, biochemistry and the like.

Just for good measure, here also are a few other links to some interesting discussions appearing in Nature recently on our gut microbiota and the Barker hypothesis. All I will say is 'all hail our gut bacteria' and onwards with the epigenetic revolution.

Happy reading!

P.S. I know I have been neglecting this blog for a few weeks and apologise. I will hopefully devote more time to it as the year goes on. In the meantime, a link to a peculiar song which has been running through my mind for a few week now.. Gotye and 'Somebody that I used to know' (UK readers might have heard this as an advert for 2Day 2012 from BBC Radio 2).

* Kumar V. et al. From genome-wide association studies to disease mechanisms: celiac disease as a model for autoimmune diseases. Seminars in Immunopathology. May 2012
DOI: 10.1007/s00281-012-0312-1

Probiotics, probiotics, probiotics

Do you ever have one of those days where a certain word seems to keep cropping up again and again no matter where you turn? Well, today is one of those days for me, and today's word is probiotics. Like a good dose of influenza (if there is such a thing as a good dose), I just can't seem to shake that word today.

So here are the papers with that word:

Delzenne and colleagues* (open-access) report on an interesting relationship between gut bacteria and obesity with a specific focus on studies looking to 'alter' the gut microbiota via pre- and probiotics and the various reported outcomes based on anthropometric and biochemical parameters linked to obesity. I talked about something similar a few months back on a sister blog.

Min Tan and colleagues** (open-access) report on the quite positive effects to patients recovering from traumatic brain injury in intensive care following administration of probiotics. Based on a relatively small patient group, patients (n=52) were randomised into either a nutrition + probiotics group or a nutrition alone group. Feeds were administered via a nasogastric tube initially which then progressed to the 'by mouth' route when patients were well enough. Various serum cytokines and related immune markers were analysed over the course of the study which lasted for 21 days.

Unfortunately some of the patients did not make it following their group allocation as sadly might be expected following a serious brain trauma. Other patients developed complications following their accident which did not seem to differ in quantity statistically between the groups aside from the number of pathogens potentially related to infections: fewer pathogens in the probiotic group. The probiotic group (the probiotic including Bifidobacterium longum, Lactobacillus bulgaricus, and Streptococcus thermophilus) did however show an altered immune profile to the control group in terms of indications of the Th1-Th2 slant to the immune system. Although perhaps a little simplistic, Th1 represents the fighting infection side of the immune system and Th2 is the production of antibodies side of things. The probiotic group showed an immune profile more representative of the Th1 response, speculated to be important for their speedier recovery and their less frequent use of antibiotics.

Although the results were not totally astounding in this study, there is an important clinical lesson from this trial in that patients spent statistically less time in intensive care and relied on fewer antibiotics during their recovery as a result of probiotic administration. For patients and physicians alike, this has got to be a good thing.

Finally, ScienceDaily carries an interesting statement from the Annual Scientific Meeting of the American College of Gastroenterology (ACG) regarding probiotics and the potential anti-inflammatory properties of certain types of probiotic. I like to sound of the collected press conference for the studies listed in this release: "Good, bad and ugly bugs: Mother Nature as a treatment for better health in the GI tract". As per the release there are a few headlines including:

• A meta-analysis of studies looking at the use of probiotics used to reduce cases of antibiotic-associated diarrhoea (diarrhea) concluded that yep, probiotics, and particularly that most lovable to yeasts Saccharomyces boulardii, do a pretty good job at curbing your risk of this quite unpleasant condition.
• The use of Bifidobacterium infantis 35624 for those suffering from recurrent abdominal bloating and discomfort did not fare too well in a new randomised-controlled trial. B.infantis 35624 had previously shown some interesting positive results for those with irritable bowel syndrome (IBS).
• Having said that, it was not all bad news for B.infantis 35624 as per another trial which suggested that the probiotic might have some pretty good anti-inflammatory properties when it comes to those dastardly pro-inflammatory cytokines. Indeed that most common of inflammatory markers, C-reactive protein seemed also to be reduced in cases of psoriasis, ulcerative colitis and even in chronic fatigue patients following probiotic administration.

What then can we assume from these collected studies. Well, at least in the short-term under various controlled conditions, probiotics, various probiotics, might just be able to influence our health and ill-health particularly in certain conditions/states. As per my previous post, our collected gut bacteria is a complicated organism which talks to our immune system in ways we are only starting to understand. Like every married couple, sometime the talk is positive and healthy; other times the talk is slightly less healthy... (not in front of the kids!).

Whether in the longer-term, supplementing with probiotics offers any added benefit, I don't know. Speculation (and it is only that) would perhaps suggest that the way probiotics are delivered (those all important enteric coatings), how our immune system recognise bacteria as 'self' or 'not-self' and good old homeostasis (the body's drive to keep harmony) are all factors potentially affecting the ability to make a more permanent shift in our not-so-good bacterial species to those preferred choices. Indeed this last point on what is good and bad gut bacteria perhaps needs a little more research in terms of the effects of individual species, etc on health and wellbeing.

* Delzeene NM. et al. Targeting gut microbiota in obesity: effects of prebiotics and probiotics. Nature Revs. November 2011.

** Min Tan. et al. Effects of probiotics on serum levels of Th1/Th2-cytokine and clinical outcomes in severe traumatic brain-injured patients: a prospective randomized pilot study. Critical Care. December 2011.