Editor's Comment: This piece of research directly supports Martin Pall's hypothesis that the production of excess nitric oxide is the basic mechanism behind ME/CFS. According to Pall, the symptoms of ME/CFS and other multi-system illnesses can be explained by a vicious cycle of inflammation created by nitric oxide and its breakdown products. This study also provides an explanation for the gut flora abnormalities and subsequent gastrointestinal problems commonly experienced by people with ME/CFS, IBS, autism, and fibromyalgia.
Host-derived nitrate boosts growth of E. coli in the inflamed gut.
~Source: Science. February 8, 2013.
By SE Winter et al.
Changes in the microbial community structure are observed in individuals with intestinal inflammatory disorders. These changes are often characterized by a depletion of obligate anaerobic bacteria, whereas the relative abundance of facultative anaerobic Enterobacteriaceae increases. The mechanisms by which the host response shapes the microbial community structure, however, remain unknown. We show that nitrate generated as a by-product of the inflammatory response conferred a growth advantage to the commensal bacterium Escherichia coli in the large intestine of mice. Mice deficient in inducible nitric oxide synthase did not support the growth of E. coli by nitrate respiration, suggesting that the nitrate generated during inflammation was host-derived. Thus, the inflammatory host response selectively enhances the growth of commensal Enterobacteriaceae by generating electron acceptors for anaerobic respiration.
Source: Science. 2013 Feb 8;339(6120):708-11. doi: 10.1126/science.1232467. Winter SE, Winter MG, Xavier MN, Thiennimitr P, Poon V, Keestra AM, Laughlin RC, Gomez G, Wu J, Lawhon SD, Popova IE, Parikh SJ, Adams LG, Tsolis RM,Stewart VJ, Bäumler AJ. Department of Medical Microbiology and Immunology, School of Medicine, University of California, Davis, One Shields Avenue, Davis, CA, USA.
Additional information about this study can be found at Science Daily.