Over the last few years, the science has emerged to prove that there is actually a close relationship between the respiratory, immune and gastrointestinal systems. We now know that a disruption to your biome (those trillions of microorganisms that live in your intestinal tract) can trigger an oversensitivity to allergens in your immune system, which could ultimately make your allergies flare up even more as a result. So, how do we support our gut? One acceptable method is to eat lots of healthy foods that are rich in fibre, as well as fermented products, such as kombucha. Of course, in
Butyric Acid Production
Butyric acid or butyrate (the ester form) is a main short chain fatty acid produced by friendly bacteria in the human gut when they feed off of certain carbohydrates, particularly non-starch fibres as well as resistant fibres. These 4- carbon fatty acids are the preferred source of energy for colonocytes ( colon cells). It is used preferentially over glucose, maintaining colonocyte activity. Butyric acids have some impressive benefits both locally and systemically as it is rapidly absorbed.
Prevent and Treat Leaky Gut
‘Leaky gut’ is the term used to describe what happens when food sensitivities, food allergies, or bacterial infections cause the intestinal wall to no longer do its job in regulating the passage of substances from entering or leaving the body. Butyric acid has been identified as being a key molecule in fortifying the cells of the colon as well as supporting the spaces in between them by creating tight junctions. Butyric acid also supports the production of key antimicrobial peptides in the mucous lining of the colon walls to prevent damage by toxins from other bacterial species. It also regulates the passage of water, preventing diarrhea.
Immune System Support and Regulation of Inflammation
Butyric acid acts on a number of immune cells, one of the key cells are neutrophils. Butyric acid activates a G-protein ( or cell signalling molecule) that causes a cascade that attracts more neutrophils leading to a stronger response. Further, butyric acids and butyrate have direct and systemic anti-inflammatory effects- particularly to prevent the inflammatory cascade ( ie COx2 and prostaglandin formation). Managing this local inflammation makes butyric acid a key therapeutic target for many inflammatory disorders such as inflammatory bowel disease (IBD).
Upregulates brain derived neurotrophic factor (BDNF) which causes growth and repair of neurons and neural plasticity. This factor is important for proper brain functioning and has been linked to improving outcomes in degenerative diseases. Further butyric acid has been shown to improve mitochondrial function for energy production and protection against neuronal cell death.
One of the proposed mechanisms of action for butyrate is the inhibition of molecules (histone deacetylase- HDAC molecules) that tighten DNA. These molecules can block key portions of DNA thereby silencing cell cycle genes. Butyric acid can inhibit these and essentially restart the production of key molecules such as the p53 transcription factor. This molecule is associated with blocking the proliferation of cancer cells and initiation of apoptosis ( or programmed cell death).
Supplementing with Butyrate
In healthy individuals we often see the formation of butyric acid as the result of fermentation by the commensal bacteria. The capacity to produce butyrate is then dependent on a) the types of bacteria present and b) the carbohydrates ingested. Butyrate enemas have also gained some traction as a way to increase the amount of these fatty acids in the GIT. A key type of bacteria that has been identified that facilitate this fermentation are Clostridium butyricum. This bacterium breaks down fibre in the gut to produce butyrate ( butyric acid). This probiotic is difficult to find in most supplements in Canada. Another important probiotic strain is Bacillus mesentericus – which supports the growth of the two aforementioned bacteria and the growth of the most common bacteria in the large intestine; the Bifidobacterium species.
Bourassa, M., Alim, I., Bultman, S., & Ratan, R.R. (2016) Butyrate, neuroepigenetics and the gut microbiome: Can a high fiber diet improve brain health? Neuroscience Letters. Volume 625:56-63. https://pubmed.ncbi.nlm.nih.gov/26868600/
Van Immerseel F, Ducatelle R, De Vos M, Boon N, Van De Wiele T, Verbeke K, Rutgeerts P, Sas B, Louis P, Flint H. (2010) Butyric acid-producing anaerobic bacteria as a novel probiotic treatment approach for inflammatory bowel disease. J. Med. Microbiol. 59(2):141-143 doi:10.1099/jmm.0.017541-0
Rolfe RD. The role of probiotic cultures in the control of gastrointestinal health. J Nutr. 2000 Feb;130(2S Suppl):396S-402S. https://pubmed.ncbi.nlm.nih.gov/19942690/
Seo G, Akimoto Y, Hamashima H, Masuda K, Shiojima K, Sakuma C, Sasatsu M, Arai T. A new factor from Bacillus mesentericus which promotes the growth of Bifidobacterium. Microbios. 2000;101(399):105-14. https://pubmed.ncbi.nlm.nih.gov/10738983/
Song ZF, Wu TX, Cai LS, Zhang LJ, Zheng XD. Effects of dietary supplementation with clostridium butyricum on the growth performance and humoral immune response in Miichthys miiuy. J Zhejiang Univ Sci B. 2006 Jul;7(7):596-602. https://pubmed.ncbi.nlm.nih.gov/16773736/