Effect of Lactobacillus reuteri NCIMB 30351 drops on symptoms of infantile functional gastrointestinal disorders and gut microbiota in early infants: Results from a randomized, placebo-controlled clinical trial

Infantile functional gastrointestinal disorders, such as colic, constipation, diarrhea, and gastroesophageal reflux (regurgitation), often occur in early infancy and, representing one of the causes of significant parental anxiety, lead to a significant strain on the healthcare resources. In this study, we aimed to evaluate the effects of Lactobacillus reuteri drops (L. reuteri NCIMB 30351) on the symptoms of infantile colic, constipation, diarrhea, and gastroesophageal reflux, as well as on the levels of intestinal microbiota in full-term newborns during the first months of life. A randomized, placebo-controlled, single-masked (blinded), post-marketing clinical study was conducted in two clinical units-Children's City Clinical Hospital of Moscow and Medical Center "St. Andrew's Hospitals-NEBOLIT" from March 2020 to May 2022 in 90 infants aged from 1 to 4 months (mean age (± SD) 12.3 ± 5.09 weeks; 53.3% females, 46.7% males). Patients with colic, regurgitation (single symptom or combination of several symptoms), and constipation or diarrhea were randomly allocated in two parallel arms to receive either 5 drops (2 × 108 colony forming unit) of L. reuteri NCIMB 30351 (n = 60) or masked placebo (n = 30) for 25 consecutive days. Two treatment arms had equal numbers of patients with constipation and diarrhea (n = 30 each). Daily crying times and their duration, evacuations, and regurgitations were recorded in a structured diary. The levels of gut microbiota were analyzed by deep sequencing of bacterial 16S rRNA gene. Infants with colic receiving supplementary L. reuteri NCIMB 30351 for 25 days had significant reduction in the numbers of colic (change from baseline - 6.3 (7.34) vs - 3.0 (7.29) in placebo, P < 0.05) and numbers of crying cases and mean duration of crying (decrease from baseline - 144 (70.7) minutes, lower in the diarrhea subgroup than in constipation infants, compared with - 80 (58.9) in placebo, P < 0.0001), as well as regurgitation numbers (decreased by - 4.8 (2.49) with L. reuteri vs - 3 (7.74) with placebo). We also observed increased numbers of evacuations in infants with constipation (L. reuteri 2.2 (2.4) vs 0.9 (1.06) in placebo, P < 0.05). There was a remarkable reduction of evacuations in infants with diarrhea, while not statistically significant. The analysis of bacterial 16S rRNA gene in the collected samples showed that L. reuteri positively influences the proportions of prevalent species, while it negatively affects both conditionally pathogenic and commensal microbes. Additional in vitro test for formation of Clostridium colonies in the presence of the probiotic demonstrated that L. reuteri effectively inhibits the growth of pathogenic Clostridium species. No adverse events were reported in this study.   Conclusion: The uptake of L. reuteri NCIMB 30351 leads to a significant reduction in the number of regurgitations, feeding-induced constipations, and diarrhea as well as mean daily numbers of crying and crying duration in infants during the first months of life. Our results suggest that L. reuteri NCIMB 30351 represents a safe and effective treatment for colic in newborns.  Trial registration: ClinicalTrials.gov : NCT04262648. What is Known: • Infantile functional gastrointestinal disorders, such as colic, constipation, diarrhea, and gastroesophageal reflux (regurgitation), often occur in early infancy and, represent one of the causes of significant parental anxiety. • A number of studies have shown that both the composition and diversity of the intestinal microbiota play important roles in the development and function of the gastrointestinal tract. What is New: • The uptake of L. reuteri NCIMB 30351 leads to a significant reduction in the number of regurgitations, feeding-induced constipations, and diarrhea as well as mean daily numbers of crying and crying duration in infants during the first months of life. • L. reuteri positively influences the proportions of prevalent species, while it negatively affects both conditionally pathogenic and commensal microbes in gut microbiota.

Unraveling the Polysaccharide Biosynthesis Potential of Ganoderma lucidum: A Chromosome-Level Assembly Using Hi-C Sequencing

Ganoderma lucidum exhibits the ability to synthesize a diverse range of biologically active molecules with significant pharmaceutical potential, including xylomannan and fucogalactan, which have demonstrated antitumor activity. However, there exists considerable intra-species variability in the capacity to produce these metabolites at high concentrations, likely reflecting the high genomic diversity observed from a limited number of strains sequenced to date. We employed high-throughput shotgun sequencing to obtain the complete genome sequence of G. lucidum strain 5.1, which is distinguished by its remarkable xylomannan synthesis capabilities. Through the utilization of semi-automatic reordering based on conformation capture (Hi-C) data, we substantially enhanced the assembly process, resulting in the generation of 12 chromosome-level scaffolds with a cumulative length of 39 Mbp. By employing both de novo and homology-based approaches, we performed comprehensive annotation of the genome, thereby identifying a diverse repertoire of genes likely involved in polysaccharide biosynthesis. The genome sequence generated in this study serves as a valuable resource for elucidating the molecular mechanisms underlying the medicinal potential of Ganoderma species, discovering novel pharmaceutically valuable compounds, and elucidating the ecological mechanisms of the species. Furthermore, the chromosome contact map obtained for the first time for this species extends our understanding of 3D fungal genomics and provides insights into the functional and structural organization within the fungal kingdom.

Gut Microbiome in Post-COVID-19 Patients Is Linked to Immune and Cardiovascular Health Status but Not COVID-19 Severity

The composition of the gut microbiome stores the imprints of prior infections and other impacts. COVID-19 can cause changes in inflammatory status that persist for a considerable time after infection ends. As the gut microbiome is closely associated with immunity and inflammation, the infection severity might be linked to its community structure dynamics. Using 16S rRNA sequencing of stool samples, we investigated the microbiome three months after the end of the disease/infection or SARS-CoV-2 contact in 178 post-COVID-19 patients and those who contacted SARS-CoV-2 but were not infected. The cohort included 3 groups: asymptomatic subjects (n = 48), subjects who contacted COVID-19 patients with no further infection (n = 46), and severe patients (n = 86). Using a novel compositional statistical algorithm (nearest balance) and the concept of bacterial co-occurrence clusters (coops), we compared microbiome compositions between the groups as well as with multiple categories of clinical parameters including: immunity, cardiovascular parameters and markers of endothelial dysfunction, and blood metabolites. Although a number of clinical indicators varied drastically across the three groups, no differences in microbiome features were identified between them at this follow-up point. However, there were multiple associations between the microbiome features and clinical data. Among the immunity parameters, the relative lymphocyte number was linked to a balance including 14 genera. Cardiovascular parameters were associated with up to four bacterial cooperatives. Intercellular adhesion molecule 1 was linked to a balance including ten genera and one cooperative. Among the blood biochemistry parameters, calcium was the only parameter associated with the microbiome via a balance of 16 genera. Our results suggest comparable recovery of the gut community structure in the post-COVID-19 period, independently of severity or infection status. The multiple identified associations of clinical analysis data with the microbiome provide hypotheses about the participation of specific taxa in regulating immunity and homeostasis of cardiovascular and other body systems in health, as well as their disruption in SARS-CoV-2 infections and other diseases.

Luminal and Tumor-Associated Gut Microbiome Features Linked to Precancerous Lesions Malignancy Risk: A Compositional Approach

Colorectal cancer is the third most commonly diagnosed cancer worldwide. Human gut microbiome plays important roles in protecting against it, as well as contributing to its onset and progression. Identification of specific bacterial taxa associated with early stages of colorectal cancer may help develop effective microbiome-based diagnostics. For precancerous lesions, links of their characteristics to luminal and tumor-associated microbiome composition are to be elucidated. Paired stool and tumor brush biopsy samples were collected from 50 patients with precancerous lesions and early forms of colon cancer; their microbial communities were profiled using high-throughput 16S rRNA sequencing. We showed that the microbiome differences between stool and biopsy samples can be to a high extent computationally corrected. Compositionality-aware statistical analysis of microbiome composition revealed its associations with the number of lesions, lesion type, location and malignization pathway. A major determinant of precancerous lesions malignancy risk-the number of lesions-was positively associated with the abundance of H2S-producing taxa. Our results contribute to the basis for developing early non-invasive colorectal cancer diagnostics via identifying microorganisms likely participating in early stages of cancer pathogenesis.

Characterization of vaginal Lactobacillus species by rplK -based multiplex qPCR in Russian women

We describe a multiplex qPCR assay for identification and quantitative assessment of a set of vaginal Lactobacillus species, including L. acidophilus, L. crispatus, L. gasseri, L. helveticus, L. iners, and L. jensenii. The assay extends the previously developed qPCR method for Lactobacillus detection and total quantification based on targeting the rplK gene. Both assays use only single pair of primers and a set of probes combined in three reactions, comprising a vaginal Lactobacillus diagnostic assay panel. The utility of the diagnostic panel was evaluated by analyzing of vaginal swab specimens from 145 patients with different status of vaginal health. Most frequently, only one Lactobacillus species was dominant (68,9%), mostly L. crispatus (18,6%) or L. iners (33,1%), but two or three Lactobacillus species were also being simultaneously detected (24,9%). The diagnostic panel will facilitate investigations of the role of Lactobacillus species in the health of the female reproductive system and promote studies of variability of the vaginal microbiota.

A novel real-time PCR assay for highly specific detection and quantification of vaginal lactobacilli

PCR detection and quantification of vaginal lactobacilli remains problematic because of the high level of genetic heterogeneity and taxonomic complexity within the genus Lactobacillus. The aim of the present study was to identify conserved sequences among the genomes of major species of vaginal lactobacilli that could be used for the development of a PCR-based method for quantitative determination of vaginal microbiota-specific lactobacilli. Comparative analysis of the genomes of several species of vaginal lactobacilli allowed us to identify conserved regions in the rplK gene, which encodes ribosomal protein L11, and to design group-specific PCR primers and a probe for selected species from the L. acidophilus complex, including major vaginal lactobacilli Lactobacillus crispatus, L. gasseri, L. iners and L. jensenii as well as other species that are less common in vaginal microbiota. The applicability of the new assay in routine diagnostic testing was evaluated using a set of clinical samples. The assay was able to detect and quantify vagina-associated lactobacilli within a wide range of initial DNA template concentrations, indicating promising potential for clinical applications.