Alteration of Immune-Mechanisms by Human Microbiota and Development and Prevention of Human Diseases

Ginseng under forest exerts stronger anti-aging effects compared to garden ginseng probably via regulating PI3K/AKT/mTOR pathway, SIRT1/NF-κB pathway and intestinal flora

BACKGROUND

Ginseng is deemed to be an effective anti-aging therapy. Evidence for differences in representative active ingredients and anti-aging effects between garden ginseng (GG) and ginseng under forest (FG) is insufficient.

PURPOSE

The study was designed to systematically analyze the differences in the mechanistic protective effects of GG and FG on aging mice based on their compositional differences.

METHODS

The chemical ingredients in GG and FG were first determined. In vivo, D-galactose-induced aging mice were orally administered GG or FG (400 mg/kg/day) for 6 weeks. Behavioral parameters of mice were measured by the radial 8-arm maze, and the changes in body weight and organ indices were recorded. Blood, brain tissue, and feces were collected for biochemical analysis, histopathological staining, Western blotting, and 16S rDNA intestinal flora sequencing, respectively.

RESULTS

The absolute contents of total ginsenosides, polyphenols, crude polysaccharides, starch, and protein in GG were 0.71, 0.68, 1.15, 2.27, and 1.08 folds higher than those in FG, respectively; while FG exhibited a higher relative abundance of representative active ingredients (total ginsenosides, polyphenols, crude polysaccharides, and protein) but lower relative content of starch than GG. GG and FG improved hippocampal lesions and poor weight gain, organ indices, and behavioral indices, and prevented excessive oxidative stress and acetylcholinesterase activity in aging mice. What's more, GG and FG treatment ameliorated excessive apoptosis and inflammatory reaction in the aging brain by modulating apoptosis-related proteins, PI3K/AKT/mTOR pathway, and SIRT1/NF-κB pathway. GG and FG also restored the diversity and structure of gut microbiota, up-regulated the relative abundance of beneficial bacteria (e.g., Lactobacillus), and tended to exert key anti-aging effects via the microbiota-gut-brain axis. Notably, in vivo experiments confirmed that FG had a stronger anti-aging activity than GG.

CONCLUSION

FG exerts a more powerful anti-aging effect than GG by regulating oxidative stress, apoptosis, inflammation, and the microbe-gut-brain axis, possibly relying on the higher relative abundance of representative active ingredients (total ginsenosides, polyphenols, crude polysaccharides, and protein) in FG.

Potential Role of Gastrointestinal Microbiota in Growth Regulation of Yellowtail Kingfish Seriola lalandi in Different Stocking Densities

A 90-day study was performed under three different stocking densities, including high density (10,000 fishes/cage), medium density (8000 fishes/cage), and low density (6000 fishes/cage), in a deep-sea net cage for yellowtail kingfish (Seriola lalandi). The physiological characteristics and growth performance were tested, and structural characteristics of the gastrointestinal microbiota were systematically analyzed. The results show that fishes with high density had a lower weight gain rate and a specific growth rate, as well as higher serum cortisol content. The diversity, types and numbers of dominant microbiota with significant differences, and the numbers of shared genera among the different groups all changed. Core genera in the gastrointestinal tract were obtained according to the principles of dominance, commonality, and difference. The changes in the relative abundance of the core genera might be related to the growth and physiological characteristics of the host. The ratio of Firmicutes to Bacteroidetes in the stomach and pyloric caecum, which favors the accumulation of energy by the host from the diet, was higher in the medium-density group than in the other groups. This indicates that the higher density could cause physiological stress and affect growth performance. In order to reduce the resulting growth differences, gastrointestinal microbiota might assist the host in accumulating energy, participating in the energy distribution by adjusting its structure. Based on the growth, physiology, and production practices, the medium density was the appropriate density in this study. This study provides a reference for the improvement of deep-sea culture technology and the promotion of healthy growth through the gastrointestinal microecological regulation of yellowtail kingfish.

Gut Microbiota Variations between Henoch-Schonlein Purpura and Henoch-Schonlein Purpura Nephritis

Background

In China, little is known regarding the differences between children with Henoch-Schonlein purpura (HSP) and Henoch-Schonlein purpura nephritis (HSPN) concerning their gut microbiota.

Methods

We recruited 25 children with HSP, 25 children with HSPN, and 25 healthy children to investigate the differences. Fecal samples were collected and analyzed by sequencing the V3-V4 region of the 16S rRNA gene. The diversity of the fecal gut microbiota was compared between the patient groups.

Results

Rarefaction curves showed that the gut microbial diversity between the three groups differed significantly (P = 0.0224). The top five most abundant gut microbial genera were Bacteroides, Faecalibacterium, Prevotella, Ruminococcaceae, and Megamonas in children with HSP; Bacteroides, Faecalibacterium, Prevotella, Bifidobacterium, and Ruminococcaceae in children with HSPN; and Bacteroides, Prevotella, Faecalibacterium, Ruminococcaceae, and Bifidobacterium in healthy children. Children with HSP had the lowest Bifidobacterium abundance among the three groups (P < 0.05). Children with HSPN had a lower abundance of Akkermansia than children with HSP (P < 0.05), whereas children with HSPN had a higher Alistipes abundance than children with HSP (P < 0.05). Fecal microbial community composition did not differ significantly between groups (ANOSIM, R = -0.002, P = 0.46). Despite the small sample size, our results indicate that children with HSP or HSPN displayed dysbiosis of the gut microbiota.

Conclusion

This study provides valuable insights that will benefit the development of future microbe-based therapies to improve clinical outcomes or prevent the incidence of HSP or HSPN in children.

Coarse Cereals and Legume Grains Exert Beneficial Effects through Their Interaction with Gut Microbiota: A Review

Coarse cereals and legume grains (CCLGs) are rich in specific macro- and functional elements that are considered important dietary components for maintaining human health. Therefore, determining the precise nutritional mechanism involved in exerting the health benefits of CCLGs can help understand dietary nutrition in a better manner. Evidence suggests that gut microbiota play a crucial role in the function of CCLGs via their complicated interplay with CCLGs. First, CCLGs modulate gut microbiota and function. Second, gut microbiota convert CCLGs into compounds that perform different functions. Third, gut microbiota mediate interactions among different CCLG components. Therefore, using gut microbiota to expound the nutritional mechanism of CCLGs is important for future studies. A precise and rapid gut microbiota research model is required to screen and evaluate the quality of CCLGs. The outcomes of such research may promote the rapid discovery, classification, and evaluation of CCLG resources, thereby opening a new opportunity to guide nutrition-based development of CCLG products.

Impact of time and temperature on gut microbiota and SCFA composition in stool samples

Gut dysbiosis has been implicated in the pathophysiology of a growing number of non-communicable diseases. High through-put sequencing technologies and short chain fatty acid (SCFA) profiling enables surveying of the composition and function of the gut microbiota and provide key insights into host-microbiome interactions. However, a methodological problem with analyzing stool samples is that samples are treated and stored differently prior to submission for analysis potentially influencing the composition of the microbiota and its metabolites. In the present study, we simulated the sample acquisition of a large-scale study, in which stool samples were stored for up to two days in the fridge or at room temperature before being handed over to the hospital. To assess the influence of time and temperature on the microbial community and on SCFA composition in a controlled experimental setting, the stool samples of 10 individuals were exposed to room and fridge temperatures for 24 and 48 hours, respectively, and analyzed using 16S rRNA gene amplicon sequencing, qPCR and nuclear magnetic resonance spectroscopy. To best of our knowledge, this is the first study to investigate the influence of storage time and temperature on the absolute abundance of methanogens, and of Lactobacillus reuteri. The results indicate that values obtained for methanogens, L. reuteri and total bacteria are still representative even after storage for up to 48 hours at RT (20°C) or 4°C. The overall microbial composition and structure appeared to be influenced more by laboratory errors introduced during sample processing than by the actual effects of temperature and time. Although microbial activity was demonstrated by elevated SCFA at both 4°C and RT, SCFAs ratios were more stable over the different conditions and may be considered as long as samples are come from similar storage conditions.

Oral Probiotics Alleviate Intestinal Dysbacteriosis for People Receiving Bowel Preparation

Background: Bowel preparation is necessary for successful colonoscopy, while it can seriously affect intestinal microbial composition and damage the intestinal mucosal barriers in humans.

Methods: To figure out whether probiotics can sustain intestinal homeostasis and guard people's health, the probiotic drug of Bifidobacterium Tetragenous viable Bacteria Tablets (P group, n = 16) or placebo (C group, n = 16) was used for volunteers receiving bowel preparation, and high-throughput sequencing method was applied to monitor their intestinal microbial changes.

Results: The present results suggested that bowel preparation obviously reduced the intestinal microbial diversity, while taking probiotics significantly restored it to normal level. In addition, probiotics sharply reduced the abundance of pathogenic Proteobacteria, and obviously lowered the ratio of Firmicutes/Bacteroidetes compared with control group at phylum level (P < 0.05). And probiotics markedly decreased the abundance of pathogenic Acinetobacter and Streptococcus, while greatly enriched the relative abundance of beneficial bacteria Bacteroides, Roseburia, Faecalibacterium, and Parabacteroides at genus level (P < 0.05).

Conclusion: Probiotic drugs, e.g., Bifidobacterium Tetragenous viable Bacteria Tablets, can be used to restore intestinal dysbacteriosis caused by bowel preparation, and reduce side effects during colonoscopy.

The Dynamic Interplay between the Gut Microbiota and Autoimmune Diseases

The human gut-resident commensal microbiota is a unique ecosystem associated with various bodily functions, especially immunity. Gut microbiota dysbiosis plays a crucial role in autoimmune disease pathogenesis as well as in bowel-related diseases. However, the role of the gut microbiota, which causes or influences systemic immunity in autoimmune diseases, remains elusive. Aryl hydrocarbon receptor, a ligand-activated transcription factor, is a master moderator of host-microbiota interactions because it shapes the immune system and impacts host metabolism. In addition, treatment optimization while minimizing potential adverse effects in autoimmune diseases remains essential, and modulation of the gut microbiota constitutes a potential clinical therapy. Here, we present evidence linking gut microbiota dysbiosis with autoimmune mechanisms involved in disease development to identify future effective approaches based on the gut microbiota for preventing autoimmune diseases.

The Dynamic Interplay between the Gut Microbiota and Autoimmune Diseases

The human gut-resident commensal microbiota is a unique ecosystem associated with various bodily functions, especially immunity. Gut microbiota dysbiosis plays a crucial role in autoimmune disease pathogenesis as well as in bowel-related diseases. However, the role of the gut microbiota, which causes or influences systemic immunity in autoimmune diseases, remains elusive. Aryl hydrocarbon receptor, a ligand-activated transcription factor, is a master moderator of host-microbiota interactions because it shapes the immune system and impacts host metabolism. In addition, treatment optimization while minimizing potential adverse effects in autoimmune diseases remains essential, and modulation of the gut microbiota constitutes a potential clinical therapy. Here, we present evidence linking gut microbiota dysbiosis with autoimmune mechanisms involved in disease development to identify future effective approaches based on the gut microbiota for preventing autoimmune diseases.

A randomised trial of probiotics to reduce severity of physiological and microbial disorders induced by partial gastrectomy for patients with gastric cancer

Gastrectomy has been widely used for the treatment of gastric cancer, and the severity of physiological and microbial disorders has greatly harmed the health of patients. In the present study, a probiotic combination containing Bifidobacterium infantis, Lactobacillus acidophilus, Enterococcus faecalis and Bacillus cereus was used to reduce the physiological disorders induced by gastrectomy via monitoring the blood index and microbial diversity using high-throughput sequencing. Our results indicated that the probiotic combination had significantly reduced the inflammation indexes (leukocyte) (p<0.05), while it markedly enhanced the immunity indexes (lymphocyte) and nutrition indexes (albumin and total protein) (p<0.05). In addition, gastric cancer had a strong influence on the microbial diversity of the stomach via enhancing the number of pathogens of Streptococcus, Peptostreptococcus and Prevotella, and reducing the percentage of the probiotic Bifidobacterium. Although partial gastrectomy markedly changed intestinal microbial diversity, the taking of the probiotic combination greatly reduced the ratio of Firmicutes/Bacteroidetes compared with patients taking no probiotics at the phylum level. At the genus level, the probiotic combination significantly enhanced the numbers of the probiotic bacteria Bacteroides, Faecalibacterium and Akkermansia and lowered the richness of Streptococcus. Therefore, we concluded that the taking of the probiotic combination significantly enhances the immune response of patients and reduces the severity of inflammation through modification of gut microbiota.