Scientists continue to study ways to replace the missing metabolites in patients who are prone to inflammatory bowel disease and colorectal cancer (colon cancer). New research, published in the American Journal of Pathology, describes the introduction of histamine-producing intestinal bacteria in mice lacking the enzyme histidine decarboxylase, reduces inflammation and tumor formation. The results indicate that the change in the intestinal microbiome using probiotics may be a new preventive measure for patients at risk for inflammatory bowel disease .
"We have to use the achievements of science microbiome to facilitate the diagnosis and treatment of diseases, - said James Versalovich, professor of pathology and immunology from Houston. - Introducing the necessary microbes, we reduce the risk of developing cancer . "
The researchers conducted a series of experiments on rodents that have lacked the enzyme necessary for the conversion of histidine to histamine. Experimental mice were injected with the probiotic Lactobacillus reuteri 6475 which is capable of converting histidine to histamine, and control animals received placebo. Mice given probiotics before and after administration of chemical agent for tumor formation, after which the tissue was sent for analysis.
Probiotic increased the expression of a bacterial enzyme and the amount of histamine in mice. Using positron-emission tomography (PET) for imaging of tumors, experts have revealed the presence of tumors and increased glucose uptake in the walls of the colon. In mice injected with the probiotic was smaller tumors and significantly decreased glucose absorption region.
Active probiotics reduced inflammation, reduced concentration of cytokine in plasma and prevent an increase in the number of myeloid cells. According to Dr. Versalovicha producing histamine probiotic L. reuteri weakens the colon carcinogenesis. The role of histamine in the formation of cancer in humans is still unclear. When the researchers analyzed data from 2153 patients with colorectal cancer, the results showed better survival in patients with high expression of the histamine receptor. These data show that the probiotics generating histamine in the presence of a sufficient amount of L-histidine protein, may improve the results in patients with cancer. "The results illustrate the role of histamine in the suppression of chronic inflammatory bowel disease and colon cancer," - said Dr. Versalovich.