• Welcome to Crohn's Forum, a support group for people with all forms of IBD. While this community is not a substitute for doctor's advice and we cannot treat or diagnose, we find being able to communicate with others who have IBD is invaluable as we navigate our struggles and celebrate our successes. We invite you to join us.

Evolving Concepts: How Diet and the Intestinal Microbiome Act as Modulators of Breast Malignancy (Very interesting regarding Crohns)

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3800670/


Now this part really got my attention:

"Human research has shown that patients with mutations in Crohn's disease genes such as nucleotide binding oligomerization domain 2 (NOD2) [33] and autophagy related protein 16L-1 (ATG16L1) [34] have decreased numbers of the Firmicutes species of bacteria Faecalibacterium prausnitzii and Roseburia intestinalis in their ileum [35]. This decrease in commensal bacteria is associated with a proportional increase in the pathogenic adherent invasive Escherichia coli and Salmonella typhimurium [36, 37]. The inability of Faecalibacterium and Roseburia to survive in the intestinal microbiome of patients with Crohn's disease deprives these patients of bacteria which produce short chain fatty acids (SCFA) used as nutrition and energy for colonocytes [38]. Decreased SCFA leads to increased colonocyte death, increased cell turnover and may explain in part the 3.2-fold higher lifetime risk of colorectal cancer observed in Crohn's when compared to general population [39, 40]. "

I asked my GI at the last scope if he could sequence my tissue from the ilieum to see what bacteria is present there. He just answered that they don´t do that...:(
 
yea this is very interesting. it seems like it might be a good piece of evidence against the theory that the missing bacteria is the first cause for the disease, but there is lots of evidence of support for this and weak evidence that contradicts it. but this might be evidence to the contrary, so i will understand it better and get back with my analysis to see how well it contradicts that theory.

at first glance, here is the actual reference they derived their statement from
http://www.ncbi.nlm.nih.gov/pubmed/20839241. i need to strictly divide if they are stating a hard observable scientific fact, or another theory or hypothesis they are evaluating.

but they said risk genes were associated with shifts in good(commensal)bacteria, now an association i think is different then a direct correlation or a cause. also, i have already read good studies that show many people have crohsn disease risk genes with no signs of crohns whatsoever, the genes only increase your risk that is all it seems to do. so these studies suggest at least nod2, does not at all guaranty anyone developing crohn's, and AGAIN points towards environment as prime factors to developing crohns disease. but ill still go over all this information to see how solid it is and if it contradicts the theory that the missing/extinct bacteria themselves are the main cause.

thanks again for mentioning this!!


EDIT:
more thoughts- they did a multivariate analysis on 154 people who had their microbiome/bacteria previously analyzed by 16srna sequencing , to try to make any connection between IBD risk genes and specific changes in bacteria and they found some associations between having the genes and having some changes in microbiome.

what they are not saying is that these genes absolutly guaranty people will have dysbiosis which is characteristic of IBD. therefore, this study seems similar to past studys that suggests IBD risk genes only mildy increase your risk of having crohn's or having dysbiosis, THEREFORE, it seems very unlikley that this is a major contributer to the disease, but may play a small role in the disease. there is nothing about this information that proves beyond all doubt that risk genes are the absolute cause of IBD, i guess that is the most important question i have, nor is this absolute conclusive proof that IBD genes are the cause of dysbiosis.

so then the possibility that extinct bacteria are the main cause of crohns, is still there.
 
Last edited:
Top