Analysis of protector mechanism of probiotics using DNA comet assay

Ecology affects human organism by causing breaks in DNA and, therefore, induce mutations and malignant cell formation. Comet assay is a quantitative method that allows to measure DNA damage in eukaryotic cells (Liao, McNutt, & Zhu, 2009). This method is widely used in areas, such as human biomonitoring, genotoxicology, and ecology. Comet assay is also called a single-cell gel electrophoresis. Thus, the products of electrophoresis are analyzed under the fluorescent light, which makes it similar to comets. DNA strand breaks are detected by comparing the intensity of the comet tail relative to the head (Collins, 2004). Probiotics containing Lactobacillus rhamnosus were used, as Lactobacilli probiotics were found to be safe and effective against urogenital diseases, food hypersensitivity, and dental caries (Lebeer, Vanderleyden, & De Keersmaeckler, 2008). The aim of the research was to study DNA protector mechanism for three probiotic products, containing L. rhamnosus

Analysis of protector mechanism of probiotics using DNA comet assay

Ecology affects human organism by causing breaks in DNA and, therefore, induce mutations and malignant cell formation. Comet assay is a quantitative method that allows to measure DNA damage in eukaryotic cells (Liao, McNutt, & Zhu, 2009). This method is widely used in areas, such as human biomonitoring, genotoxicology, and ecology. Comet assay is also called a single-cell gel electrophoresis. Thus, the products of electrophoresis are analyzed under the fluorescent light, which makes it similar to comets. DNA strand breaks are detected by comparing the intensity of the comet tail relative to the head (Collins, 2004). Probiotics containing Lactobacillus rhamnosus were used, as Lactobacilli probiotics were found to be safe and effective against urogenital diseases, food hypersensitivity, and dental caries (Lebeer, Vanderleyden, & De Keersmaeckler, 2008). The aim of the research was to study DNA protector mechanism for three probiotic products, containing L. rhamnosus

Draft genome sequence of Lactobacillus rhamnosus CLS17

The human gut microbiome is an organ that provides primary barrier protection against foreign agents. Most of the microorganisms are different strains of commensal bacteria that are colonized in the gut. Gut flora influence food metabolism and have an antagonistic effect on different pathogens and immunomodulatory properties (1). One of the main species of gut flora is in the genus Lactobacillus...This work was supported by grant 0113PK00783 from the Ministry of Education and Science of the Republic of Kazakhstan

Metagenomic analysis of gut microbial communities from a Central Asian population

OBJECTIVE: Changes in the gut microbiota are increasingly recognised to be involved in many diseases. This ecosystem is known to be shaped by many factors, including climate, geography, host nutrition, lifestyle and medication. Thus, knowledge of varying populations with different habits is important for a better understanding of the microbiome. DESIGN: We therefore conducted a metagenomic analysis of intestinal microbiota from Kazakh donors, recruiting 84 subjects, including male and female healthy subjects and metabolic syndrome (MetS) patients aged 25-75 years, from the Kazakh administrative centre, Astana. We characterise and describe these microbiomes, the first deep-sequencing cohort from Central Asia, in comparison with a global dataset (832 individuals from five countries on three continents), and explore correlations between microbiota, clinical and laboratory parameters as well as with nutritional data from Food Frequency Questionnaires. RESULTS: We observe that Kazakh microbiomes are relatively different from both European and East Asian counterparts, though similar to other Central Asian microbiomes, with the most striking difference being significantly more samples falling within the Prevotella-rich enterotype, potentially reflecting regional diet and lifestyle. We show that this enterotype designation remains stable within an individual over time in 82% of cases. We further observe gut microbiome features that distinguish MetS patients from controls (eg, significantly reduced Firmicutes to Bacteroidetes ratio, Bifidobacteria and Subdoligranulum, alongside increased Prevotella), though these overlap little with previously published reports and thus may reflect idiosyncrasies of the present cohort. CONCLUSION: Taken together, this exploratory study describes gut microbiome data from an understudied population, providing a starting point for further comparative work on biogeography and research on widespread diseases. TRIAL REGISTRATION NUMBER: ISRCTN37346212; Post-results

Effect of Celergen, a marine derivative, on in vitro hepatocarcinogenesis

The aim of this study was to test for a potential anticarcinogenic effect of Celergen, a marine derivative devoid of traceable amounts of inorganic arsenic, on cell proliferation, cell cycle progression and apoptosis in the HepG2 human liver cancer cell line. Celergen significantly inhibited the proliferation of cancer cells in a dose-dependent manner while limiting the cell cycle progression at the G1 phase and significantly inducing apoptosis. Further examination showed that Celergen enhanced expression of the p21CIPl1WAF1, GADD153 genes and downregulated the c-myc gene. These results suggest that Celergen exerts promising chemopreventive properties to be further investigated

Dynamic changes in microbiome composition following Mare's milk intake for prevention of collateral antibiotic effect

INTRODUCTION: Probiotics and prebiotics are widely used for recovery of the human gut microbiome after antibiotic treatment. High antibiotic usage is especially common in children with developing microbiome. We hypothesized that dry Mare's milk, which is rich in biologically active substances without containing live bacteria, could be used as a prebiotic in promoting microbial diversity following antibiotic treatment in children. The present pilot study aims to determine the impacts of dry Mare's milk on the diversity of gut bacterial communities when administered during antibiotic treatment and throughout the subsequent recovery phase. METHODS: Six children aged 4 to 5 years and diagnosed with bilateral bronchopneumonia were prescribed cephalosporin antibiotics. During the 60 days of the study, three children consumed dry Mare's milk whereas the other three did not. Fecal samples were collected daily during antibiotic therapy and every 5 days after antibiotic therapy. Total DNA was isolated and taxonomic composition of gut microbiota was analyzed by 16S rRNA amplicon sequencing. To assess the immune status of the gut, stool samples were analyzed by bead-based multiplex assays. RESULTS: Mare's milk treatment seems to prevent the bloom of Mollicutes, while preventing the loss of Coriobacteriales. Immunological analysis of the stool reveals an effect of Mare’s milk on local immune parameters under the present conditions

Subspecies in the global human gut microbiome

Population genomics of prokaryotes has been studied in depth in only a small number of primarily pathogenic bacteria, as genome sequences of isolates of diverse origin are lacking for most species. Here, we conducted a large-scale survey of population structure in prevalent human gut microbial species, sampled from their natural environment, with a culture-independent metagenomic approach. We examined the variation landscape of 71 species in 2,144 human fecal metagenomes and found that in 44 of these, accounting for 72% of the total assigned microbial abundance, single-nucleotide variation clearly indicates the existence of sub-populations (here termed subspecies). A single subspecies (per species) usually dominates within each host, as expected from ecological theory. At the global scale, geographic distributions of subspecies differ between phyla, with Firmicutes subspecies being significantly more geographically restricted. To investigate the functional significance of the delineated subspecies, we identified genes that consistently distinguish them in a manner that is independent of reference genomes. We further associated these subspecies-specific genes with properties of the microbial community and the host. For example, two of the three Eubacterium rectale subspecies consistently harbor an accessory pro-inflammatory flagellum operon that is associated with lower gut community diversity, higher host BMI, and higher blood fasting insulin levels. Using an additional 676 human oral samples, we further demonstrate the existence of niche specialized subspecies in the different parts of the oral cavity. Taken together, we provide evidence for subspecies in the majority of abundant gut prokaryotes, leading to a better functional and ecological understanding of the human gut microbiome in conjunction with its host

Short-chain fatty acid propionate protects from hypertensive cardiovascular damage

BACKGROUND: Arterial hypertension and its organ sequelae show characteristics of T cell mediated inflammatory diseases. Experimental anti-inflammatory therapies have been shown to ameliorate hypertensive end-organ damage. Recently, the CANTOS study targeting interleukin-1β demonstrated that anti-inflammatory therapy reduces cardiovascular risk. The gut microbiome plays pivotal role in immune homeostasis and cardiovascular health. Short-chain fatty acids (SCFA) are produced from dietary fiber by gut bacteria and affect host immune homeostasis. Here, we investigated effects of the SCFA propionate in two different mouse models of hypertensive cardiovascular damage. METHODS: To investigate the effect of SCFA on hypertensive cardiac damage and atherosclerosis, wild-type NMRI (WT) or ApoE(-/-) deficient mice received propionate (200mM) or control in the drinking water. To induce hypertension, WT mice were infused with Angiotensin (Ang)II (1.44mg/kg/d s.c.) for 14 days. To accelerate the development of atherosclerosis, ApoE(-/-) mice were infused with AngII (0.72mg/kg/d s.c.) for 28 days. Cardiac damage and atherosclerosis were assessed using histology, echocardiography, in vivo electrophysiology, immunofluorescence, and flow cytometry. Blood pressure was measured by radiotelemetry. Regulatory T cell (Treg) depletion using PC61 antibody was used to examine the mode of action of propionate. RESULTS: Propionate significantly attenuated cardiac hypertrophy, fibrosis, vascular dysfunction, and hypertension in both models. Susceptibility to cardiac ventricular arrhythmias was significantly reduced in propionate-treated AngII-infused WT mice. Aortic atherosclerotic lesion area was significantly decreased in propionate-treated ApoE(-/-). Systemic inflammation was mitigated by propionate treatment, quantified as a reduction in splenic effector memory T cell frequencies and splenic T helper 17 cells in both models, and a decrease in local cardiac immune cell infiltration in WT mice. Cardioprotective effects of propionate were abrogated in Treg-depleted AngII-infused mice, suggesting the effect is Treg-dependent. CONCLUSIONS: Our data emphasize an immune-modulatory role of SCFAs and their importance for cardiovascular health. The data suggest that lifestyle modifications leading to augmented SCFA production could be a beneficial non-pharmacological preventive strategy for patients with hypertensive cardiovascular disease