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All posts for the month July, 2015

Several of my friends suffer from fibromyalgia. I wondered if there was a possible link between the fatigue and muscle pain (myalgia) they suffer, and I found this interesting article from the Journal of the American Medical Association, authored by Henry C. Lin: “Small intestinal bacterial overgrowth: a framework for understanding irritable bowel syndrome“.

Now, bear with me, this article is not just about irritable bowel syndrome (IBS)- in the abstract it mentions, at the very end, how the distinction between small intestinal bacterial overgrowth and IBS may focus on a specific set of symptoms that exclude fatigue and muscle pain, while diagnoses of chronic fatigue and fibromyalgia are focused mainly on these symptoms. The authors of the article suggest that this distinction may be academic- an artefact of medical training- and put forth the idea that maybe all these various symptoms can be traced to a single cause, namely, gut dysbiosis (here specifically focusing on small intestinal bacterial overgrowth).

This is a hugely important and interesting idea, and taken along with the article I have mentioned in my preceding post, a review of the gut-brain axis (where changes in gut microflora can result in psychological changes), gut dysbiosis (unhealthy gut microflora) may contribute not only to symptoms like muscle pain and fatigue, but to mood disorders as well.

The obvious question for people suffering from these symptoms is, how can I fix my gut microbiome, if it might be unhealthy? This is a hugely important question. Right now research is focusing on finding “good guy bacteria” that can help maintain healthy states, but it’s important to remember that it’s not enough to simply take a probiotic- if you take bacteria and add them to an environment where they can’t grow and establish, they will simply pass right on through your intestines without making much of a change. It’s known that factors such as what you eat, how much and when you exercise, how much and when you sleep, and if you’ve become sick (food poisoning, for example) will all affect the composition of your gut microflora. Establishing a healthy microbiome will probably require that you follow a doctor’s advice with all these factors and do so in a steady, long-term fashion- not that you simply take a probiotic supplement or eat fancy bacteria-containing yogurt.

[UPDATE: There are a TON of quack websites out there which claim to have miracle diets or cures for small intestinal bacterial overgrowth (SIBO): if you read anything like that, stop! It’s fake! It won’t help and might harm you. SIBO treatments have to be custom-tailored for each person. Please take the above cited article and this one to a real medical doctor, not a naturopath, and if you look at websites make sure they are from reputable, accredited medical schools.]

In future, I am hoping that work based on ideas I have might help people whose gut microbiomes are unhealthy and, for whatever reason, can’t take probiotics, or in whom probiotics are not effective (probably because the gut environment is hostile to those added bacteria). Right now I am focusing on an interesting strain of Lactobacillus that helps fight lymphoma, but the lessons I learn from this organism may help me study ways to use other gut bacteria with different kinds of effects on human health, to help a lot more people.

Hello readers! I have downloaded the most interesting- and high quality- review I could find on links between gut bacteria and brain functioning/mood, and it is can be found via this link: “Gut-brain axis: how the microbiome influnces anxiety and depression”. The journal is Cell and the review is written by Jane A. Foster and Karen-Anne McVey Neufeld, both of McMaster University.

I haven’t had time to read all the articles listed in Table 1, which is an outline of different kinds of studies done with mice and the psychological effects of changes in gut microbiota. However, while I plan to discuss these works in more detail in the future, I’d like to direct your attention to Figure 1 in this article: it nicely sums up the different, and interconnected, effects that changes in gut bacterial community composition (or, changes in your gut microbiome) have on your body, including your brain. A change on one partner (your body, or your gut microbiota) will have feedback effects on the other partner, which then leads to additional changes to the first partner.

Figure 1 caption (I’ve added additional notes in italics): Bidirectional (two-way) communication between gut microbiota and components of the gut–brain axis which influence normal homeostasis (the state your body is in when you are healthy, and the systems which maintain that state) and may contribute to risk of disease. Alterations in gastrointestinal (GI), central nervous system (CNS), autonomic nervous system (ANS), and immune systems by microbiota may lead to alterations in (a) fat storage and energy balance (or, you may find yourself prone to changes in weight); (b) GI barrier function (the GI barrier keeps your gut from “leaking” and allowing in antigens that cause inflammatory responses, which if unchecked can lead to disease states like colitis); (c) general low-grade inflammation (GI and systemic, or body-wide); (d) increased stress reactivity (or you are more sensitive to stressors); and (e) increased anxiety and depressive-like behaviors. Each of these mechanisms is implicated in the pathophysiology (disease physiology) of mood and anxiety disorders.

I apologize for not having an explanation of this article ready for consumption today, but please stay tuned for it in coming weeks.

Hello, blog readers! I apologize, for I have sadly neglected you- and I failed to update this blog with summaries of the many interesting articles that have crossed my desk. I have been taking courses in bioinformatics, and travelling- and one of my travels took me to Duke University where I met with one of my collaborators in person for the first time.

While I was there, I received email notification that the small grant I had applied for in June was not going to be funded. I hadn’t expected it to be- only four of those grants are funded out of however many applications they get, and so it is a very competitive program. My co-PI and I still await the reviewers’ commentary on our application.

However, all is not lost- it’s been decided that my Duke collaborator will help me apply for an NIH R21 grant, which would allow everyone (not just the Canadians) to be paid from the grant. My Duke collaborator and I sat down that afternoon and put our heads together, and came up with a marvellously scribble-filled page of notes for the project we think we should do- and it is bigger, better, and if funded will be an amazing piece of science! I am slowly putting all our thoughts into words- slowly because I am still waiting for feedback on our first grant application, which will inform this one, and also slowly because the deadline for this program is in October, though I believe we can apply earlier than that.

So my trip to Duke was not simply an exercise in networking, it was very fruitful and I’m so glad that I was able to do that! Stay tuned for more updates on the R21. Again, these are competitive grants, and it’s possible our application won’t be funded- but it won’t be for lack of our trying, or doing the best job we possibly can.

I hope to post a few more summaries of interesting research articles in the coming weeks- it’s been hard to find the time, as I am responsible for putting together this R21, other personal writing projects have caught my attention and, as always, I still have a full-time job that I have responsibilities toward. Still, every week new and interesting research on the subject of gut bacteria and how they affect their animal hosts is published, much of it not very accessible to the general public. I’d like to share more of these articles with you in hopes that you find the work as interesting and informative as I do.