Intestinal Microecological Balance Research Articles

Research Progress of Fecal Microbiota Transplantation in Liver Diseases.

A growing body of evidence suggested that gut microbiota is associated with liver diseases through the gut-liver axis. The imbalance of gut microbiota could be correlated with the occurrence, development, and prognosis of a series of liver diseases, including alcoholic liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), viral hepatitis, cirrhosis, primary sclerosing cholangitis (PSC), and hepatocellular carcinoma (HCC). Fecal microbiota transplantation (FMT) seems to be a method to normalize the patient's gut microbiota. This method has been traced back to the 4th century. In recent decade, FMT has been highly regarded in several clinical trials. As a novel approach to reconstruct the intestinal microecological balance, FMT has been used to treat the chronic liver diseases. Therefore, in this review, the role of FMT in the treatment of liver diseases was summarized. In addition, the relationship between gut and liver was explored through the gut-liver axis, and the definition, objectives, advantages, and procedures of FMT were described. Finally, the clinical value of FMT therapy in liver transplant (LT) recipients was briefly discussed.

Amelioration of colitis progression by ginseng-derived exosome-like nanoparticles through suppression of inflammatory cytokines

BackgroundDamage to the healthy intestinal epithelial layer and regulation of the intestinal immune system, closely interrelated, are considered pivotal parts of the curative treatment for inflammatory bowel disease (IBD). Plant-based diets and phytochemicals can support the immune microenvironment in the intestinal epithelial barrier for a balanced immune system by improving the intestinal microecological balance and may have therapeutic potential in colitis. However, there have been only a few reports on the therapeutic potential of plant-derived exosome-like nanoparticles (PENs) and the underlying mechanism in colitis. This study aimed to assess the therapeutic effect of PENs from Panax ginseng, ginseng-derived exosome-like nanoparticles (GENs), in a mouse model of IBD, with a focus on the intestinal immune microenvironment. MethodTo evaluate the anti-inflammatory effect of GENs on acute colitis, we treated GENs in Caco2 and lipopolysaccharide (LPS) -induced RAW 264.7 macrophages and analyzed the gene expression of pro-inflammatory cytokines and anti-inflammatory cytokines such as TNF-α, IL-6, and IL-10 by real-time PCR (RT-PCR). Furthermore, we further examined bacterial DNA from feces and determined the alteration of gut microbiota composition in DSS-induced colitis mice after administration of GENs through 16S rRNA gene sequencing analysis. ResultGENs with low toxicity showed a long-lasting intestinal retention effect for 48 h, which could lead to effective suppression of pro-inflammatory cytokines such as TNF-α and IL-6 production through inhibition of NF-κB in DSS-induced colitis. As a result, it showed longer colon length and suppressed thickening of the colon wall in the mice treated with GENs. Due to the amelioration of the progression of DSS-induced colitis with GENs treatment, the prolonged survival rate was observed for 17 days compared to 9 days in the PBS-treated group. In the gut microbiota analysis, the ratio of Firmicutes/Bacteroidota was decreased, which means GENs have therapeutic effectiveness against IBD. Ingesting GENs would be expected to slow colitis progression, strengthen the gut microbiota, and maintain gut homeostasis by preventing bacterial dysbiosis. ConclusionGENs have a therapeutic effect on colitis through modulation of the intestinal microbiota and immune microenvironment. GENs not only ameliorate the inflammation in the damaged intestine by downregulating pro-inflammatory cytokines but also help balance the microbiota on the intestinal barrier and thereby improve the digestive system.

A Comparative Study of Serum Pharmacochemistry of Kai-Xin-San in Normal and AD Rats Using UPLC-LTQ-Orbitrap-MS.

Kai-Xin-San (KXS) is a classic formula for the treatment of Alzheimer's disease (AD). KXS has been widely used to treat emotional diseases; however, its active components remain unknown. There have been some reports about the efficacy and metabolic analysis of KXS, which are mainly based on studying normal animals. The current work first established an AD rat model by injecting D-galactose into the abdominal cavity and injecting Aβ25-35 into the hippocampus on both sides, followed by intragastric administration of KXS for a consecutive week; then, the analytical method for ethanol extraction from the serum of normal and model rats was developed using UPLC-LTQ-Orbitrap-MS; finally, the transitional components in the blood were systematically compared and analyzed by multivariate statistical analysis. A total of 36 components of KXS were identified in the rat serum of the normal group, including 24 prototype components (including ginsenosides, triterpenoid acids of Poria cocos, polygala saponins, polygala xanthones and polygala ester) and 13 metabolites (including desugar, hydration and oxidation products of ginsenosides, triterpenoid acid hydroxylation, deoxygenation, demethylation, desaturation, and glycine-conjugated products of Poria cocos). Twenty KXS-relevant components were detected in the rat serum of the model group, including 11 prototypes and 9 metabolites. The normal group and the model group shared 12 common components, including 9 prototypes and 3 metabolites. The intestinal microecological balance of the model rats probably was destroyed, affecting the absorption/metabolism of saponins by the body, which resulted in fewer transitional components in the model group. This study reflected the drug-body interaction from an objective and accurate perspective, offering references and insights for elucidating the basis of active components and mechanism of action of KXS for treating AD.

Butyrate ameliorates colorectal cancer through regulating intestinal microecological disorders.

The occurrence and progression of colorectal cancer (CRC) are closely related to intestinal microecological disorders. Butyrate, the representative of short chain fatty acids, possess anti-inflammatory and antioxidant effects, and its antitumor effect has been gradually paid attention to. In this study, azoxymethane/dextran sodium sulfate induced mouse CRC model was used to explore the role and mechanism of butyrate in regulating colon cancer and its intestinal microecological balance. Outcomes exhibited that butyrate alleviated weight loss, disease activity index, and survival in CRC mice and inhibited tumor number and progression. Further research revealed that butyrate restrained the aggregation of harmful while promoting the colonization of beneficial flora, such as Actinobacteriota, Bifidobacteriales and Muribaculacea through 16S rDNA sequence analysis. This study confirmed that butyrate can ameliorate CRC by repairing intestinal microecology, providing ideas and evidence for chemical prophylactic agents, such as butyrate to remedy tumors and regulate tumor microbiota.

Herbal medicine in the treatment of COVID-19 based on the gut-lung axis.

http://links.lww.com/AHM/A33.

Lactobacillus mucosae exerted different antiviral effects on respiratory syncytial virus infection in mice.

Respiratory syncytial virus (RSV) infection is a constant threat to the health of young children, and this is mainly attributed to the lack of effective prevention strategies. This study aimed to determine whether Lactobacillus (L.) mucosae, a potential probiotic, could protect against respiratory viral infection in a mouse model. Naive 3–4-week-old BALB/c mice were orally administered with three L. mucosae strains (2.5 × 108 CFU/mouse) 7 days before RSV infection (105 TCID50/mouse). Results showed that all three strains inhibited RSV replication and reduced the proportions of inflammatory cells, including granulocytes and monocytes in the blood. The L. mucosae M104R01L3 treatment maintained stable weight in mice and increased interferon (IFN)-β and tumor necrosis factor (TNF)-α levels. The L. mucosae DCC1HL5 treatment increased interleukin (IL)-1β and IL-10 levels. Moreover, the M104R01L3 and DCC1HL5 strains increased the proportions of Akkermansia, Alistipes, and Anaeroplasma which contributed to the advantageous modulation of the gut microbiota. Besides, L. mucosae affected the gut levels of short-chain fatty acids (SCFAs) that are important for the antiviral response. L. mucosae 1,025 increased acetate, propionate, and butyrate levels, whereas L. mucosae M104R01L3 increased the level of acetate in the gut. L. mucosae M104R01L3 may protect against viral infection by upregulating the IFN-β levels in the lungs and its antiviral effect may be related to the increase of acetate levels in the gut. In conclusion, the three L. mucosae strains exerted antiviral effects against RSV infection by differentially regulating immune responses and intestinal micro-ecological balance. This study can provide a reference for studying the mechanisms underlying the antiviral effects of L. mucosae.

Research on the correlation between intestinal microecology and leukemia

Intestinal microecology is the largest and most complex microecological community in the human body and is closely related to human health. About 20% of malignancies are associated with microecological dysbiosis. The gut microbiota of patients with leukemia is significantly different from that of the healthy population. The intestinal flora can be involved in the development and progression of leukemia in many ways through regulation of immune cells, stimulation of inflammation, infection by pathogenic bacteria, action of metabolites, influence of body metabolism and genetic mutations. Chemotherapy, allogeneic hematopoietic stem cell transplantation and chimeric antigen receptor T-cell immunotherapy can cause intestinal flora disorders in leukemia patients, and probiotic therapy can reduce the complications associated with the treatment process. The intestinal microecological stability is beneficial to the treatment of leukemia patients, therefore, the in-depth exploration of methods to maintain the intestinal microecological balance is important for the prolongation of survival of leukemia patients.

Combination of microbiome and metabolome to analyze the cross-synergism mechanism of inulin and gut microbiota in vitro and vivo

Inulin can regulate the intestinal micro-ecological balance, but there are few studies on the changes of intestinal microbiota and its metabolites in vitro and vivo, SCFAs and amino acids in particular. In this study, the human fecal microbiota glycolysis model and a mouse model were used to study the mechanism of inulin on intestinal microecology. Combined with metabolism of microbiome and metabolome, the cross-synergism mechanism of inulin-micribiota-metabolites-metabolism was investigated. The results revealed that after inulin was fermented by human intestinal microbiota, the relative abundance of Lactobacillus, Bifidobacterium, Prevotella, Catenibacterium, and Agathobacter increased. In vivo, the concentration of SCFAs increased after inulin was fermented, and the abundance of Parabacteroides, Muribaculaceae and Alloprevotella increased. Both in vivo and in vitro experiments revealed that inulin can regulate the expression of 5 genes involved in Valine, leucine and isoleucine degradation. In addition, the metabolome results confirmed that Valine, leucine and isoleucine degradation, Tyrosine metabolism, and Synthesis and degradation of ketone bodies are regulatory pathways of inulin. More importantly, L−tryptophan, tyrosine, L−fucose, L−ornithine, D−fructose, D−erythrose, and pyruvic acid are hallmark metabolites of inulin metabolized by gut microbiota. The cross-synergism network greatly indicated the microbiota (Streptococcus, Lactobacillus, Muribaculaceae), metabolites (l-tryptophan, pyruvic acid), and metabolism (Lysine degradation, Tryptophan metabolism, Synthesis and degradation of ketone bodies) may be the key factors involved in the mechanisms regulating the in vitro and vivo effects of inulin.

Effect of fresh and spray-dried microalgal diets on the growth, digestive enzymatic activity, and gut microbiota of juvenile winged pearl oyster Pteria penguin

The effects of fresh and spray-dried microalgal diets on the growth, digestive enzymatic activity, and gut microbial community were investigated in juveniles of the winged pearl oyster Pteria penguin. A total of 240 pearl oysters were fed either live or spray-dried unialgal diets of the species Isochrysis zhanjiangensis and Platymonas subcordiformis at a final concentration of 150,000 cells/mL. The experiment was performed over 28 days in triplicate feeding trials under laboratory conditions. At the end of the feeding trials, the hepatopancreas and gut tissue were dissected to quantify the digestive enzymatic activity and analyze the gut bacterial community. The survival rate of the oyster juveniles in all trials was > 90 %. Moreover, the animals fed a spray-dried P. subcordiformis diet exhibited slightly higher shell growth rates. However, the mean shell height and the total wet weight were not significantly different among all experimental groups (P > 0.05). The digestive enzymes amylase, pepsin, and lipase exhibited significantly higher activity levels in oysters fed spray-dried diets than in those provided live microalgae. The different diets also provoked changes in the gut microbiota of the pearl oysters. A total of 27 phyla and 482 genera were detected within all groups examined; the Proteobacteria, Cyanobacteria, Bacteroidetes, and Spirochaetes were the dominant phyla. In general, spray-dried diets exhibited a higher number of operational taxonomic units (OTUs), Chao1, and Simpson and Shannon indices, implying the ability of these diets to promote high microbial biodiversity. Thus, these diets benefitted the maintenance of the intestinal micro-ecological balance and health. The study findings will help optimize intermediate culture technology and management of P. penguin juveniles.

Dietary olive oil enhances the oral tolerance of the food allergen ovalbumin in mice by regulating intestinal microecological homeostasis.

Increasing evidence indicates that intestinal microecological imbalances are strongly associated with food allergen intolerance. This study investigated the effect of olive oil on food allergy susceptibility and intestinal microecology based on an ovalbumin (OVA)-sensitized mouse model. The results indicated that the allergic symptoms of sensitized mice were alleviated when they were supplemented with olive oil at 1-3g/kg per day for 7 weeks. Intestinal epithelium observation showed repaired ileum villi and upregulated tight junction (TJ) protein expression. Furthermore, the levels of the cytokines (e.g., IL-10) secreted by regulatory T cells were increased, whereas T helper 2 (Th2) cell-associated factors were decreased in lamina propria. Furthermore, 16S rRNA sequencing indicated reduced Burkholderiaceae and increased Clostridiaceae in the intestinal microflora. The results suggest that an olive oil-enriched diet may effectively prevent food allergies by regulating the intestinal microecological balance. PRACTICAL APPLICATIONS: Recent studies emphasized that intestinal ecological imbalance, including intestinal immunity and microflora structure, plays an important role in affecting the occurrence and development of food allergy. The present results implied that olive oil, one of the main components of the Mediterranean diet, can effectively ameliorate the symptoms of OVA-induced food allergy by regulating intestinal microecological homeostasis. Therefore, dietary supplementation with olive oil may be an effective strategy for preventing food allergies.

Regulatory Effect of Lactiplantibacillus plantarum 2-33 on Intestinal Microbiota of Mice With Antibiotic-Associated Diarrhea.

Diarrhea is one of the common adverse reactions in antibiotic treatment, which is usually caused by the imbalance of intestinal flora, and probiotics play an important role in the structure of intestinal flora. Therefore, this experiment studied the regulatory effect of Lactiplantibacillus plantarum 2-33 on antibiotic-associated diarrhea (AAD) mice. First, the AAD mice model was established by the mixed antibiotic solution of gentamicin sulfate and cefradine. Then, the physiological indexes and diarrhea of mice were observed and recorded by gastric perfusion of low dose (1.0 × 107 CFU/ml), medium dose (1.0 × 108CFU/ml), and high dose (1.0 × 109 CFU/ml) strain 2-33. 16S rRNA gene V3-V4 regions were sequenced in colon contents of mice in control group, model group, self-healing group, and experimental group, respectively, and the diversity of intestinal flora and gene function prediction were analyzed. The results showed that the intestinal flora of AAD mice was not significantly regulated by gastric perfusion of strain 2-33 to 7 days, but the relative abundance and diversity of intestinal flora of AAD mice were significantly improved by gastric perfusion to 14 days (p < 0.05). In addition, at the genus level, the relative abundance of Lactobacillus increased significantly, and the relative abundance of Enterococcus and Bacillus decreased significantly (p < 0.05). In addition, the regulation of strain 2-33 on intestinal flora of AAD mice was time- and dose-dependent, short-term gastric perfusion, and low dose had no significant effect (p > 0.05). Strain 2-33 can significantly increase the levels of anti-inflammatory cytokines IL-4 and IL-10, significantly decrease the levels of proinflammatory cytokines TNF-α and IFN-γ (p < 0.05), and can also adjust carbohydrate metabolism, amino acid metabolism, and energy metabolism to normal levels, thus accelerating the recovery of intestinal flora structure of AAD mice. In summary, strain 2-33 can improve the structure and diversity of intestinal flora of AAD mice, balance the level of substance and energy metabolism, and play a positive role in relieving diarrhea, maintaining and improving the intestinal microecological balance.

Effect of Oral Chinese Herbal Preparations Regulating Intestinal Flora on Lipid Metabolism Disorders in Patients: A Meta-Analysis of Controlled Clinical Studies.

BackgroundLipid metabolism disorders can damage human health, and the changes in human intestinal flora are closely related to lipid metabolism disorders. Traditional Chinese medicine (TCM) can play a role in regulating intestinal flora and balancing intestinal microecology. In this meta-analysis, the role of oral preparations of TCM that regulate intestinal flora, in the prevention and treatment of lipid metabolism disorders, was systematically evaluated.MethodsThe databases CBM, Pubmed, Embase, CNKI, Wanfang, and Google Scholar were searched by rapid matching of keywords to obtain clinical controlled studies related to oral preparations of TCMs regulating intestinal flora. After screening and quality evaluation, meta-analysis was performed using Review Manager 5.3 software.ResultsTotal of 835 patients were enrolled in the 10 articles included in this study. Meta-analysis showed that TCM intervention could reduce the level of total cholesterol (TC) in patients with abnormal lipid metabolism [mean difference (MD) = −0.61, 95% confidence interval (95%CI) (−0.80, −0.42), p < 0.00001], reduce triacylglycerol (TG) level [MD = −0.46, 95%CI (−0.60, −0.33), p < 0.00001], increase high-density lipoprotein (HDL) level [MD = 0.25, 95%CI (0.17, 0.34), p < 0.00001], reduce the number of intestinal enterobacteria [MD = −0.64, 95%CI (−0.79, −0.49), p < 0.00001], reduce the number of enterococci [MD = −1.14, 95%CI (−1.66, −0.63), p < 0.00001], increase the number of intestinal lactobacillus [MD = 0.41, 95%CI (0.09, 0.74), p = 0.01], and increase the number of intestinal bifidobacteria [MD = 0.94, 95%CI (0.20, 1.68), p = 0.01].ConclusionThe application of oral preparations of TCMs that regulate intestinal flora, in the prevention and treatment of lipid metabolism disorders, can increase the colonization of beneficial bacteria in the intestine of patients, inhibit the growth of harmful bacteria, and restore the intestinal microecological balance, thus indirectly acting on the regulation of blood lipids in patients and contributing to the recovery of dyslipidemia.

Probiotic Effects of Bacillus licheniformis DSM5749 on Growth Performance and Intestinal Microecological Balance of Laying Hens.

This study was conducted to investigate the effects of Bacillus licheniformis DSM5749 on the production performance and intestinal health in laying hens. A total of 32-week-old laying hens (Hyline Brown) were randomly assigned to two dietary groups (10 replicates of 27 laying hens), namely, basal diet and basal diet complemented with 200 g/t B. licheniformis (3.2 × 109 CFU/kg). The trial lasted for 8 weeks, and samples were collected at the last week. Results revealed that B. licheniformis DSM5749 significantly improved laying performance, including an increase in egg production rate and average daily egg yield, and a decrease in the feed-to-egg ratio during the entire 8-week experimental period (P < 0.05). B. licheniformis DSM5749 increased the levels of superoxide dismutase and glutathione peroxidase in the liver and decreased the IL-1 level in the serum (P < 0.05). In addition, the integrity of intestinal morphology (villus height, crypt depth, and villus height/crypt depth), tight junctions (ZO-1, Claudin-1, and Occludin), and lipase vitality in the intestine were potentiated by B. licheniformis DSM5749 in laying hens (P < 0.05). B. licheniformis DSM5749 decreased the Firmicutes/Bacteroidetes ratio (P < 0.05) in the cecum. Furthermore, B. licheniformis DSM5749 modulated the microbiota in the cecum of the laying hens, increased the relative abundance of beneficial bacteria (e.g., Prevotella) at the genus level and decreased the relative abundance of potential pathogens (e.g., Desulfovibrio). In conclusion, B. licheniformis DSM5749 can improve laying performance, promote intestinal health, affect the composition of cecal microorganisms, and regulate the intestinal micro-ecological balance, making B. licheniformis a good probiotic candidate for application in the laying hens industry.

Plant Polysaccharides Modulate Immune Function via the Gut Microbiome and May Have Potential in COVID-19 Therapy.

Plant polysaccharides can increase the number and variety of beneficial bacteria in the gut and produce a variety of active substances, including short-chain fatty acids (SCFAs). Gut microbes and their specific metabolites have the effects of promoting anti-inflammatory activity, enhancing the intestinal barrier, and activating and regulating immune cells, which are beneficial for improving immunity. A strong immune system reduces inflammation caused by external viruses and other pathogens. Coronavirus disease 2019 (COVID-19) is still spreading globally, and patients with COVID-19 often have intestinal disease and weakened immune systems. This article mainly evaluates how polysaccharides in plants can improve the immune system barrier by improving the intestinal microecological balance, which may have potential in the prevention and treatment of COVID-19.

Effective Regulation of Gut Microbiota With Probiotics and Prebiotics May Prevent or Alleviate COVID-19 Through the Gut-Lung Axis.

Coronavirus disease 2019 (COVID-19) can disrupt the gut microbiota balance, and patients usually have intestinal disorders. The intestine is the largest immune organ of the human body, and gut microbes can affect the immune function of the lungs through the gut-lung axis. Many lines of evidence support the role of beneficial bacteria in enhancing human immunity, preventing pathogen colonization, and thereby reducing the incidence and severity of infection. In this article, we review the possible approach of modulating microbiota to help prevent and treat respiratory tract infections, including COVID-19, and discuss the possibility of using probiotics and prebiotics for this purpose. We also discuss the mechanism by which intestinal micro-flora regulate immunity and the effects of probiotics on the intestinal micro-ecological balance. Based on this understanding, we propose the use of probiotics and prebiotics to modulate gut microbiota for the prevention or alleviation of COVID-19 through the gut-lung axis.

Potential Application of Tea Polyphenols to the Prevention of COVID-19 Infection: Based on the Gut-Lung Axis.

Coronavirus disease 2019 (COVID-19) disrupts the intestinal micro-ecological balance, and patients often develop the intestinal disease. The gut is the largest immune organ in the human body; intestinal microbes can affect the immune function of the lungs through the gut-lung axis. It has been reported that tea polyphenols (TPs) have antiviral and prebiotic activity. In this review, we discussed TPs reduced lung-related diseases through gut-lung axis by inhibiting dysbiosis. In addition, we also highlighted the preventive and therapeutic effects of TPs on COVID-19 complications, further demonstrating the importance of research on TPs for the prevention and treatment of COVID-19 in humans. Based on this understanding, we recommend using TPs to regulate the gut microbiota to prevent or alleviate COVID-19 through the gut-lung axis.

Role of Dietary Supplements and Probiotics in Modulating Microbiota and Bone Health: The Gut-Bone Axis.

Osteoporosis is characterized by an alteration of bone microstructure with a decreased bone mineral density, leading to the incidence of fragility fractures. Around 200 million people are affected by osteoporosis, representing a major health burden worldwide. Several factors are involved in the pathogenesis of osteoporosis. Today, altered intestinal homeostasis is being investigated as a potential additional risk factor for reduced bone health and, therefore, as a novel potential therapeutic target. The intestinal microflora influences osteoclasts’ activity by regulating the serum levels of IGF-1, while also acting on the intestinal absorption of calcium. It is therefore not surprising that gut dysbiosis impacts bone health. Microbiota alterations affect the OPG/RANKL pathway in osteoclasts, and are correlated with reduced bone strength and quality. In this context, it has been hypothesized that dietary supplements, prebiotics, and probiotics contribute to the intestinal microecological balance that is important for bone health. The aim of the present comprehensive review is to describe the state of the art on the role of dietary supplements and probiotics as therapeutic agents for bone health regulation and osteoporosis, through gut microbiota modulation.

Optimization of an economical medium composition for the coculture of Clostridium butyricum and Bacillus coagulans

Clostridium butyricum is a spore-forming probiotic which can promote the enhancement of beneficial bacteria and maintain intestinal microecological balance. However, it is difficult to improve the production level of C. butyricum by conventional fermentation process. In this study, a co-fermentation process of C. butyricum DL-1 and Bacillus coagulans ZC2-1 was established to improve the viable counts and spore yield of C. butyricum, and the formula of coculture medium was optimized by flask fermentation. The results showed that the optimum medium composition is 10 g/L bran, 15 g/L corn steep powder, 15 g/L peptone, 1 g/L K2HPO4 and 0.5 g/L MnSO4.Cultured stationarily in the optimal medium for 36 h, the number of viable bacteria of C. butyricum DL-1 reached 1.5 × 108 cfu/mL, Which was 375 times higher than that incubated in the initial medium. The sporulation rate reach 92.6%. The results revealed an economical and effective medium composition for the coculture of C. butyricum and B. coagulans, which achieved a 64.6% cost reduction. The co-fermentation process established in this study provides a new fermentation mode for the industrial production of other absolute anerobic bacteria.

Precision Postbiotics and Mental Health: the Management of Post-COVID-19 Complications.

The health catastrophe originated by COVID-19 pandemic construed profound impact on a global scale. However, a plethora of research studies corroborated convincing evidence conferring severity of infection of SARS-CoV-2 with the aberrant gut microbiome that strongly speculated its importance for development of novel therapeutic modalities. The intense exploration of probiotics has been envisaged to promote the healthy growth of the host, and restore intestinal microecological balance through various metabolic and physiological processes. The demystifying effect of probiotics cannot be defied, but there exists a strong skepticism related to their safety and efficacy. Therefore, molecular signature of probiotics termed as “postbiotics” are of paramount importance and there is continuous surge of utilizing postbiotics for enhancing health benefits, but little is explicit about their antiviral effects. Therefore, it is worth considering their prospective role in post-COVID regime that pave the way for exploring the pastoral vistas of postbiotics. Based on previous research investigations, the present article advocates prospective role of postbiotics in alleviating the health burden of viral infections, especially SARS-CoV-2. The article also posits current challenges and proposes a futuristic model describing the concept of “precision postbiotics” for effective therapeutic and preventive interventions that can be used for management of this deadly disease.

Bacillus Subtilis Promotes the Release of 5-HT to Regulate Intestinal Peristalsis in STC Mice via Bile Acid and Its Receptor TGR5 Pathway.

Slow transit constipation (STC) is caused by intestinal peristalsis dysfunction and is closely associated with disturbance of the intestinal microecological balance. Bacillus subtilis plays a positive role in the treatment of STC, but its mechanism needs to be further explored. The purpose of the present study was to explore the effects and mechanism of B. subtilis on the pathophysiology of STC. A STC mouse model was established with compound diphenoxylate, following which B. subtilis was used to treat STC. The effects and possible mechanism of B. subtilis on STC were investigated by assessing intestinal motility, histology of the colon, release of 5-HT in enterochromaffin cells (ECs) and the TGR5/TRPA1 pathway. Moreover, LC-MS targeted metabolomics was used to analyze the regulation of Bacillus subtilis on bile acid metabolisms in STC mice. Bacillus subtilis significantly increased 24h defecations, fecal moisture and intestinal transport rate of STC mice, improved pathological damage of the colon and showed protective effects on the intestinal tract. The release of 5-HT from ECs and the bile acid receptor TGR5/TRPA1 pathway were significantly increased in STC mice treated with B. subtilis. In addition, the metabolomics results showed that the bile acid contents of STC mice were significantly decreased, and B. subtilis could increase the bile acid composition and content of STC mice. Bacillus subtilis regulates intestinal peristalsis of STC by promoting the release of 5-HT from ECs through bile acid metabolism and its receptor TGR5 pathway and plays a positive role in the treatment of STC.