Effects of Dietary Grape Seed Meal Bioactive Compounds on the Colonic Microbiota of Weaned Piglets With Dextran Sodium Sulfate-Induced Colitis Used as an Inflammatory Model

Bacillus subtilis JATP3 improved the immunity of weaned piglets by improving intestinal flora and producing citalopram

The purpose of this study was to evaluate the ability of Bacillus subtilis JATP3 to stimulate immune response and improve intestinal health in piglets during the critical weaning period. Twelve 28-day-old weaned piglets were randomly divided into two groups. One group was fed a basal diet, while the other group was fed a basal diet supplemented with B. subtilis JATP3 (1 × 109 CFU/mL; 10 mL) for 28 days. The results revealed a significant increase in the intestinal villus gland ratio of weaned piglets following the inclusion of B. subtilis JATP3 (P < 0.05). Inclusion of a probiotic supplement improve the intestinal flora of jejunum and ileum of weaned piglets. Metabolomics analysis demonstrated a notable rise in citalopram levels in the jejunum and ileum, along with elevated levels of isobutyric acid and isocitric acid in the ileum. The results of correlation analysis show that indicated a positive correlation between citalopram and microbial changes. Furthermore, the probiotic-treated group exhibited a significant upregulation in the relative expression of Claudin, Zonula Occludens 1 (ZO-1), and Interleukin 10 (IL-10) in the jejunum and ileum, while displaying a noteworthy reduction in the relative expression of Interleukin 1β (IL-1β). Overall, these findings suggest that B. subtilis JATP3 can safeguard intestinal health by modulating the structure of the intestinal microbiota and their metabolites, wherein citalopram might be a key component contributing to the therapeutic effects of B. subtilis JATP3.

Review article: The complex interplay between diet and Escherichia coli in inflammatory bowel disease

BACKGROUND

Although no causative microbe has been yet identified or successfully targeted in the treatment of inflammatory bowel disease (IBD), the role of Escherichia coli in the pathogenesis of Crohn's disease has attracted considerable interest.

AIM

In this review, we present a literature overview of the interactions between diet and E. coli and other Proteobacteria in the aetiology, outcomes and management of IBD and suggest future research directions.

METHODS

An extensive literature search was performed to identify in vitro studies and research in animal models that explored mechanisms by which dietary components can interact with E. coli or Proteobacteria to initiate or propagate gut inflammation. We also explored the effect diet and dietary therapies have on the levels of E. coli or Proteobacteria in patients with IBD.

RESULTS

Preclinical data suggest that the Western diet and its components influence the abundance, colonisation and phenotypic behaviour of E. coli in the gut, which may in turn initiate or contribute to gut inflammation. In contrast, the Mediterranean diet and specific dietary fibres may abrogate these effects and protect from inflammation. There are limited data from clinical trials, mostly from patients with Crohn's disease during treatment with exclusive enteral nutrition, with findings often challenging observations from preclinical research. Data from patients with ulcerative colitis are sparse.

CONCLUSIONS

Preclinical and some clinical trial data suggest that E. coli and other Proteobacteria interact with certain dietary components to promote gut inflammation. Well-designed clinical trials are required before dietary recommendations for disease management can be made.

Oral gamma-cyclodextrin-encapsulated tributyrin supplementation in young pigs with experimentally induced colitis

Disruption of intestinal integrity and barrier function due to tissue inflammation has negative implications on overall growth and well-being in young pigs. In this study, we investigated the effects of oral gamma-cyclodextrin-encapsulated tributyrin (TBCD) in young pigs experiencing dextran sodium sulfate (DSS)-induced colitis. Pigs (n = 32 boars) were weaned from the sow at postnatal day (PND) 2, allotted to treatment based on the litter of origin and body weight (BW), and reared artificially over a 26-d feeding period. Treatment groups included: 1) nutritionally adequate (control) milk replacer, no DSS (Control n = 8), 2) control milk replacer plus oral DSS (DSS, n = 7), and 3) control diet supplemented with 8.3 g of TBCD per kg of reconstituted milk replacer plus oral DSS (TBCD + DSS, n = 8). Colitis was induced by administering DSS at 1.25 g of DSS/kg BW daily in a reconstituted milk replacer from PND 14-18. Milk replacer and water were provided ad libitum throughout the 26-d study. All the data were analyzed using a one-way ANOVA using the MIXED procedure of SAS. Control and DSS pigs had similar BW throughout the study, while TBCD + DSS pigs exhibited decreased (P < 0.05) BW starting at approximately PND 15. Additionally, average daily gain (ADG) before and after initiation of DSS dosing, along with over the total study duration, was decreased (P < 0.05) in pigs receiving TBCD + DSS compared with the Control. Milk disappearance was decreased (P < 0.05) in TBCD + DSS pigs when compared with Control and DSS groups. Both the concentration and molar ratio of cecal butyrate concentrations were increased (P < 0.05) in TBCD + DSS pigs compared with the Control group. The DSS and TBCD + DSS treatments also increased (P < 0.05) butyrate concentrations in the luminal contents with the proximal colon compared with Control. TBCD + DSS and DSS pigs had increased (P < 0.05) mucosal width in the distal colon compared with Control, thereby indicating heightened intestinal inflammation. Overall, oral supplementation of encapsulated tributyrin increased the concentration of butyrate in the colon, but was unable to mitigate the negative effects of DSS-induced colitis.

Grape By-Products as Feedstuff for Pig and Poultry Production

Grape by-products are exceptional options for replacement of conventional and unsustainable feed sources, since large amounts are generated every year from the winery industry. However, the majority is wasted with severe environmental and economic consequences. The present review aimed to evaluate the effects of grape by-products on pig and poultry growth performance. The most recent literature was reviewed using ScienceDirect and PubMed databases and the results of a total of 16 and 38 papers for pigs and poultry, respectively, were assessed. Fewer studies are documented for pig, but the incorporation of grape by-products up to 9% feed led to an improvement in growth performance with an increase in average daily gain. Conversely, lower levels (<3% feed) are needed to achieve these results in poultry. The beneficial effects of grape by-products on animal performance are mainly due to their antioxidant, antimicrobial, and gut morphology modulator properties, but their high level of cell wall lignification and content of polyphenolic compounds (e.g., tannin) limits nutrient digestion and absorption by monogastric animals. The use of exogenous enzymes or mechanical/chemical processes can provide additional nutritional value to these products by improving nutrient bioavailability. Overall, the valorization of grape by-products is imperative to use them as feed alternatives and intestinal health promoters, thereby contributing to boost circular agricultural economy.

Nuciferine Regulates Immune Function and Gut Microbiota in DSS-Induced Ulcerative Colitis

Nuciferine, a major aporphine alkaloid obtained from the leaves of Nelumbo nucifera, exhibits anti-cancer and anti-inflammatory properties; however, its protective effects against inflammatory bowel diseases (IBD) has never been explored. In this study, an ulcerative colitis (UC) model was established in BALb/c mice by the continuous administration of 5% dextran sulfate sodium (DSS) in drinking water for 1 week. From day 8 to day 14, the DSS-treated mice were divided into a high-dose and a low-dose nuciferine treatment group and were intraperitoneally injected with the corresponding dose of the drug. Body weight loss, disease activity index (DAI), and colon length were measured. Histological changes were observed using hematoxylin and eosin staining. T lymphocyte proliferation was assessed by MTT assay. The ratio of CD3+, CD4+, CD8+, Th1, Th2, Th17, and Treg cells were estimated by flow cytometry. Finally, 16S rRNA sequencing was performed to compare the composition and relative abundance of the gut microbiota among the different treatment groups. The results showed that nuciferine treatment led to a significant improvement in symptoms, such as histological injury and colon shortening in mice with DSS-induced UC. Nuciferine treatment improved the Th1/Th2 and Treg/Th17 balance in the DSS-induced IBD model, as well as the composition of the intestinal microflora. At the phylum level, compared with the control group, the abundance of Firmicutes and Actinobacteriota was decreased in the model group, whereas that of Bacteroidetes increased. Meanwhile, at the genus level, compared with the control group, the numbers of the genera Lachnospiraceae_Clostridium, Bilophila and Halomonas reduced in the model group, while those of Bacteroides, Parabacteroides, and Paraprevotella increased. Notably, nuciferine administration reversed this DSS-induced gut dysbiosis. These results indicated that nuciferine modulates gut microbiota homeostasis and immune function in mice with DSS-induced UC.

Mesalamine-Mediated Amelioration of Experimental Colitis in Piglets Involves Gut Microbiota Modulation and Intestinal Immune Cell Infiltration

Mesalamine (MES), also known as 5-aminosalicylic acid, is effective in treating mild to moderate ulcerative colitis (UC). The mechanisms of its actions are not fully elucidated. The aim of this study was to investigate the effects of MES treatment on intestinal microbiota and immune system in an dextran sulfate sodium (DSS)-induced UC model in postweaning piglets. Eighteen weaned piglets were assigned randomly to the following treatments: control group (CON, distilled water), DSS group (DSS, 3% DSS), and MES group (MES, 3% DSS + 2 g/day MES). Our results showed that MES treatment alleviates DSS-induced colitis in piglets, as evidenced by a reduced diarrhea index score and increased average daily gain (P < 0.05). This is accompanied by decreased diamine oxidase activity, D-lactate level (P < 0.05), and attenuated mucosal damage. MES treatment also decreased the abundance of Methanogens and reduced colon CD11b⁺ macrophage and CD3⁺ T-cell infiltrations in piglets with DSS-induced colitis (P < 0.05). Collectively, these data indicate that MES treatment-mediated colitis protection may involve microbiota and immune cell alterations.

Medicinal Plants and Their Impact on the Gut Microbiome in Mental Health: A Systematic Review

Background: Various neurocognitive and mental health-related conditions have been associated with the gut microbiome, implicating a microbiome–gut–brain axis (MGBA). The aim of this systematic review was to identify, categorize, and review clinical evidence supporting medicinal plants for the treatment of mental disorders and studies on their interactions with the gut microbiota. Methods: This review included medicinal plants for which clinical studies on depression, sleeping disorders, anxiety, or cognitive dysfunction as well as scientific evidence of interaction with the gut microbiome were available. The studies were reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Results: Eighty-five studies met the inclusion criteria and covered thirty mental health-related medicinal plants with data on interaction with the gut microbiome. Conclusion: Only a few studies have been specifically designed to assess how herbal preparations affect MGBA-related targets or pathways. However, many studies provide hints of a possible interaction with the MGBA, such as an increased abundance of health-beneficial microorganisms, anti-inflammatory effects, or MGBA-related pathway effects by gut microbial metabolites. Data for Panax ginseng, Schisandra chinensis, and Salvia rosmarinus indicate that the interaction of their constituents with the gut microbiota could mediate mental health benefits. Studies specifically assessing the effects on MGBA-related pathways are still required for most medicinal plants.

Polyphenols as modulators of pre-established gut microbiota dysbiosis: State-of-the-art

The human intestine contains an intricate ecological community of bacteria, referred as the gut microbiota, which plays a pivotal role in the host homeostasis. Multiple factors could interfere with this delicate balance, thus causing a disruption of the microbiota equilibrium, the so called dysbiosis. Gut microbiota dysbiosis is involved in gastrointestinal and extra-intestinal metabolic diseases, as obesity and diabetes. Polyphenols, present in a broad range of plant foods, are known to have numerous health benefits; however, their beneficial effect on pre-existing dysbiosis is less clear. Indeed, in most of the conducted animal studies the administration of polyphenols or foods rich in polyphenols occurred simultaneously with the induction of the pathology to be examined, then analyzing the preventive action of the polyphenols on the onset of dysbiosis, while very low studies analyzed the modulatory activity of polyphenols on the pre-existing dysbiosis. For this reason, the present review aims to update the current information about the modulation of the pre-established gut microbiota dysbiosis by dietary phenolic compounds in a broad range of disorders in both animal studies and human trials, distinguishing the preventive or treatment approaches in animal studies. The described studies highlight that dietary polyphenols, exerting prebiotic-like effects, can modulate the pre-existing dysbiosis stimulating the growth of beneficial bacteria and inhibiting pathogenic bacteria in both animal models and humans. Anyway, most of the conducted studies are related to obesity and metabolic syndrome, and so further studies are needed to understand this polyphenols' ability in relation to other pathologies.

Impact of zinc oxide, benzoic acid and probiotics on the performance and cecal microbiota of piglets

Background

Intestinal health remains a key factor in animal production because it is essential for digestion, absorption and bacterial fermentation. Feed additives have been used to attenuate the weaning stress such as Zinc Oxide (ZnO) and benzoic acid (C₇H₆O₂). The objective of this study was to evaluate the impact of of benzoic acid and probiotics (BA + P) on performance, diarrhea and cecal microbiota of piglets in the nursery phase (23 to 65 days).

Results

One hundred and sixty weaned piglets with an initial weight of 6.335 ± 0.698 kg and 23 days of age were submitted to four treatments: supplementation with 2500 ppm of Zinc oxide (ZnO), supplementation with a commercial blend of benzoic acid and probiotics (Bacillus licheniformis, Bacillus subtilis and Enterococcus faecium NCIMB 10415; Vevogut P®) (BA + P), supplementation with Zinc oxide plus benzoic acid and probiotics (ZnO + BA + P), and controls receiving only the basal diet without any supplementation. At 65 days of age, 32 piglets (n = 8 per treatment) were slaughtered for the evaluation of the cecal microbiota. Supplementation with ZnO and BA + P were associated with better feed conversion (P < 0.05) in the early stage (23 to 49 days) and with an improvement in all performance parameters over the entire experimental period. The occurrence of diarrhea was lower (P < 0.05) in the BA + P group. The 4 most abundant phyla along with unclassified bacteria represented 93% of all sequences. Firmicutes dominated the cecal microbiota of all groups, followed by Bacteroidetes. Richness represented by the observed number of genera and by the Chao index were statistically lower in ZnO and ZnO + BA + P supplemented animals compared to controls. The beta diversity analysis that compares similarities between bacterial communities demonstrated formation of two distinct clusters containing samples with and without supplementation with ZnO, confirming a strong influence of ZnO on the intestinal microbiota.

Conclusion

The use of Benzoic acid with probiotics yields similar performance results with lower impact on the gut microbiota compared to ZnO, and it should be considered as a potential alternative in swine production.

Supplementary Information

The online version contains supplementary material available at 10.1186/s42523-021-00151-y.

Dietary Grape Seed Meal Bioactive Compounds Alleviate Epithelial Dysfunctions and Attenuates Inflammation in Colon of DSS-Treated Piglets

Inflammatory Bowel Diseases (IBD) are chronic inflammations associated with progressive degradation of intestinal epithelium and impairment of the local innate immune response. Restoring of epithelial integrity and of the mucosal barrier function, together with modulation of inflammatory and innate immune markers, represent targets for alternative strategies in IBD. The aim of our study was to evaluate the effects of a diet including 8% grape seed meal (GSM), rich in bioactive compounds (polyphenols, polyunsaturated fatty acids (PUFAs), fiber) on the markers of colonic epithelial integrity, mucosal barrier function, pro-inflammatory, and innate immunity in DSS-treated piglets used as animal models of intestinal inflammation. Our results have demonstrated the beneficial effects of bioactive compounds from dietary GSM, exerted at three complementary levels: (a) restoration of the epithelial integrity and mucosal barrier reinforcement by modulation of claudins, Occludin (OCCL) and Zonula-1 (ZO-1) tight junction genes and proteins, myosin IXB (MYO9B) and protein tyrosine phosphatase (PTPN) tight junction regulators and mucin-2 (MUC2) gene; (b) reduction of pro-inflammatory MMP-2 (matrix metalloproteinase-2) and MMP-9 (matrix metalloproteinase-9) genes and activities; and (c) suppression of the innate immune TLR-2 (Toll-like receptor-2) and TLR-4 (Toll-like receptor-4) genes and attenuation of the expression of MyD88 (Myeloid Differentiation Primary Response 88)/MD-2 (Myeloid differentiation factor-2) signaling molecules. These beneficial effects of GSM could further attenuate the transition of chronic colitis to carcinogenesis, by modulating the in-depth signaling mediators belonging to the Wnt pathway.