Disturbances in the composition of the human gastrointestinal microbiome are closely related to lifestyle, diet and exposure to stress. The literature shows great progress in the study of the composition of the intestinal microbiome and its impact on autoimmune diseases, colorectal cancer, tooth decay, and the relationship between the microbiome and the brain (impact on depression and autism). The influence of the mother’s microbiome on colonization of the newborn’s organism by the placenta or even on premature birth is also investigated. An important element of the research is to assess the impact of environmental changes on the microbiome and the development of civilization diseases, especially diabetes, obesity and cancer.
In 2015, it was estimated that antibiotic-resistant pathogens cause around 50,000 deaths annually in Europe and the US, and the death toll will increase to 10 million deaths annually worldwide by 2050. These data suggest that we are nearing the end of the antibiotic age. Antibiotics, especially beta-lactam and fluoroquinolones, the use of which lead to diarrhea and colitis, are closely related to changes in the composition and function of the gastrointestinal microbiome. Studies have shown that five days of fluoroquinolone administration eliminated or suppressed about one-third of the stool microbiome after three to four days of antibiotic therapy. Rebuilding the population was possible within a week of completing therapy, but this rebuild was incomplete.
Moreover, it is predicted that the etiology of 15% of neoplastic diseases is associated with bacterial infections. This may be due to the fact that some commensal bacteria are able to convert procarcinogens into DNA damaging compounds (e.g. ethanol, heterocyclic amines) or directly produce carcinogens (e.g. fecapentaenes) and stimulate the production of oxygen free radicals (e.g. Enterococcus faecalis) ), which increases the risk of developing colorectal cancer.
There is an increasing relationship between disturbances in the composition of the gastrointestinal microbiome and obesity. Turnbaugh et al. (2006) proved that the composition of the gut microbiome influences body weight. The authors carried out the transfer of microorganisms from the intestines of homozygous obese ob / ob mice. (mice genetically deficient in leptin due to a nonsense mutation in codon 105 of the ob gene) and normal gut weight mice into germ free mice (free from all detectable microorganisms and parasites). After two weeks, it was observed that mice that had been transplanted into the microbiome from obese mice obtained more calories from their food and showed faster fat deposition. Additionally changes in the gut microbiome induce inflammation and obesity by affecting intestinal epithelial cells, enteroendocrine cells, and intestinal hormone secretion such as glucagon-like peptides 1 and 2 (GLP-1 and GLP-2). GLP-1 stimulates insulin secretion, delays the passage of food through the stomach, induces satiety and weight loss, GLP-2 increases glucose transport from the intestines and lowers the permeability of the intestinal wall. Thus, the microbiome influences metabolism by acting on enteroendocrine cells.
Moreover, intestinal bacteria participate in the maturation and exchange of enterocytes, immunomodulation, gastrointestinal motor activity, drug metabolism, breakdown of toxins and carcinogens present in food (e.g. heterocyclic amines, N-nitroso compounds), fermentation of undigested food components, and the production of essential vitamins (K , B12, folic acid, B1, B6), in the recirculation of bile acids (by the production of bile acid hydrolases), as well as in preventing intestinal colonization by pathogenic bacteria such as Escherichia coli, Vibrio cholerae, Clostridium spp., Salmonella spp. And Shigella spp.
Methodology
In the first stage of the work, the variability of selected groups of microorganisms that make up the fecal microbiome of people: healthy, physically active, declaring not taking antibiotics (for a period of at least 1 year), eating rationally and in accordance with the basic principles of healthy eating, not consuming alcohol ( control group); people over the age of 75; patients 2 weeks after the end of antibiotic therapy; patients after completed chemotherapy and obese people (BMI> 30) and a standardized inoculum simulating the intestinal microbiome was prepared. Standardized inoculation of the intestinal microbiome came from donors from the above-mentioned groups and contained probiotic bacteria (Lactobacillus and Bifidobacterium genus), bacteria (mainly) that stimulated immunity (non-pathogenic E. coli and Enterococcus genus), as well as potentially pathogenic microbiota (proteolytic bacteria, so-called putrefactive). , bacteria of the genus Clostridium and yeast-like fungi of the genus Candida).
The presence and number of microorganisms from a given group varied depending on the origin of the inoculum. Microbiological media appropriate for a given type were used for the isolation and determination of the number of microorganisms.
Results
Picture 1 Effect of a liquid probiotic product on qualitative and quantitative changes intestinal microbiome of healthy people
Legend: blue bars – the number of microorganisms in a standardized inoculum derived from the intestinal microbiome; red bars – the number of microorganisms in a standardized inoculum derived from the intestinal microbiome after in vitro digestion in the presence of a liquid probiotic product
Conclusions
The presence of organic acids in the probiotic product resulted in a significant reduction of undesirable microorganisms of the genus Clostridium and E.coli.
Microbes from other groups remained at a similar level compared to the inoculum, which may indicate that the microbiome from healthy people shows high resistance to organic acids and is characterized by good vitality.
Picture 2. Effect of a liquid probiotic product on qualitative and quantitative changes the gut microbiome of the elderly
Legend: blue bars – the number of microorganisms in a standardized inoculum derived from the intestinal microbiome; red bars – the number of microorganisms in a standardized inoculum derived from the intestinal microbiome after in vitro digestion in the presence of a liquid probiotic product
Conclusions
After the use of the probiotic product, the majority of the determined groups of microorganisms were reduced in the composition of the intestinal microbiome.
In addition, complete elimination of undesirable microorganisms, i.e. proteolytic bacteria and yeast-like fungi, was observed.
The microorganisms that are part of the intestinal microbiome of the elderly may be characterized by reduced vitality and increased sensitivity to organic acids and polyphenols.
Picture nr 3. Effect of a liquid probiotic product on qualitative and quantitative changes intestinal microbiome in people after antibiotic therapy
Legend: blue bars – the number of microorganisms in a standardized inoculum derived from the intestinal microbiome; red bars – the number of microorganisms in a standardized inoculum derived from the intestinal microbiome after in vitro digestion in the presence of a liquid probiotic product
Conclusions
After using the probiotic product, an increase in the number of microorganisms with probiotic potential was observed.
In addition, a reduction of undesirable microorganisms such as bacteria of the genus Clostridium, proteolytic bacteria, and yeast-like fungi was observed.
Picture nr 4. Effect of a liquid probiotic product on qualitative and quantitative changes gut microbiome in people treated with chemotherapeutic drugs
Legend: blue bars – the number of microorganisms in a standardized inoculum derived from the intestinal microbiome; red bars – the number of microorganisms in a standardized inoculum derived from the intestinal microbiome after in vitro digestion in the presence of a liquid probiotic product
Conclusions:
The use of a probiotic product resulted in the complete elimination of yeast-like fungi.
In addition, a reduction in the size of most microbial groups was observed, which may indicate a strong weakening of the vitality of the microbiome that has been exposed to toxic substances (chemotherapeutic agents).
Picture nr 5. Effect of a liquid probiotic product on qualitative and quantitative changes gut microbiome of obese people
Legend: blue bars – the number of microorganisms in a standardized inoculum derived from the intestinal microbiome; red bars – the number of microorganisms in a standardized inoculum derived from the intestinal microbiome after in vitro digestion in the presence of a liquid probiotic product
Conclusions:
The use of the probiotic product resulted in the reduction of all groups of microorganisms, except for Bifidobacterium and proteolytic bacteria.
Increasing the number of bacteria of the genus Bifidobacterium is beneficial because it leads to a qualitative and quantitative equalization between the Firmicutes group (Lactobacillus bacteria) and Bifidobacteriales.
Source: Research on the evaluation of the quality and biofunctionality of the probiotic products of Living Food Sp. z o.o .. Scientific Monograph, 2019.
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