Limosilactobacillus johnsoni and Limosilactobacillus mucosae and Their Extracellular Vesicles Alleviate Gut Inflammatory Injury by Mediating Macrophage Polarization in a Lipopolysaccharide-Challenged Piglet Model

Comprehensive cultivation of the broiler gut microbiota guides bacterial isolation from chickens

Chicken gut microbiota plays an important role in maintaining their physiological health. However, the cultivability of chicken gut microbiota is not well understood, limiting the exploration of certain key gut bacteria in regulating intestinal health and nutritional metabolism. This study aimed to examine the cultivability of chicken cecal microbiota and to provide guidance for future chicken gut microbiota cultivation. A total of 58 different culture conditions were applied to culture broiler cecal microbiota, and the culture-dependent (CD; pooled colonies form each plate) and culture-independent (CI; broiler cecal contents) samples were collected for 16S rRNA gene sequencing and microbial analysis. The CD methods detected higher microbial richness (3,636 vs 2,331 OTUs) than CI methods, and the recovery rates of bacterial OTUs and genera reached 43.6% and 68.9%, respectively. The genera of Bacteroides (19.9%), Alistipes (11.0%) and Barnesiella (10.7%) were highly abundant detected by CI methods, however, there occupied a small proportion (<1.0%) of total cultured microbiota in CD methods. We then developed reference figures and tables showing optimal cultivation conditions for different gut bacteria taxa. Moreover, 81 different lactic acid bacteria strains covering 5 genera were isolated, and 15 strains had less than 97.0% similarity to known bacteria in the national center for biotechnology information (NCBI) online database. Overall, this study provides preliminary guidance in culturing specific gut microbiota from chickens, which will contribute to future studies to characterize the biological functions of key microbes in chicken nutritional metabolism and health.

Galactooligosaccharides and Limosilactobacillus reuteri synergistically alleviate gut inflammation and barrier dysfunction by enriching Bacteroides acidifaciens for pentadecanoic acid biosynthesis

Ulcerative colitis (UC) is a debilitating inflammatory bowel disease characterized by intestinal inflammation, barrier dysfunction, and dysbiosis, with limited treatment options available. This study systematically investigates the therapeutic potential of a synbiotic composed of galactooligosaccharides (GOS) and Limosilactobacillus reuteri in a murine model of colitis, revealing that GOS and L. reuteri synergistically protect against intestinal inflammation and barrier dysfunction by promoting the synthesis of pentadecanoic acid, an odd-chain fatty acid, from Bacteroides acidifaciens. Notably, the synbiotic, B. acidifaciens, and pentadecanoic acid are each capable of suppressing intestinal inflammation and enhancing tight junction by inhibiting NF-κB activation. Furthermore, similar reduction in B. acidifaciens and pentadecanoic acid levels are also observed in the feces from both human UC patients and lipopolysaccharide-induced intestinal inflammation in pigs. Our findings elucidate the protective mechanism of the synbiotic and highlight its therapeutic potential, along with B. acidifaciens and pentadecanoic acid, for UC and other intestinal inflammatory disorders.

The emerging role of bacterial extracellular vesicles in human cancers

Bacterial extracellular vesicles (BEVs) have emerged as pivotal mediators between bacteria and host. In addition to being crucial players in host homeostasis, they have recently been implicated in disease pathologies such as cancer. Hence, the study of BEVs represents an intriguing and rapidly evolving field with substantial translational potential. In this review, we briefly introduce the fundamentals of BEV characteristics, cargo and biogenesis. We emphatically summarize the current relationship between BEVs across various cancer types, illustrating their role in tumorigenesis, treatment responses and patient survival. We further discuss the inherent advantages of BEVs, such as stability, abundance and specific cargo profiles, that make them attractive candidates for non-invasive diagnostic and prognostic approaches. The review also explores the potential of BEVs as a strategy for cancer therapy, considering their ability to deliver therapeutic agents, modulate the tumour microenvironment (TME) and elicit immunomodulatory responses. Understanding the clinical significance of BEVs may lead to the development of better-targeted and personalized treatment strategies. This comprehensive review evaluates the current progress surrounding BEVs and poses questions to encourage further research in this emerging field to harness the benefits of BEVs for their full potential in clinical applications against cancer.

Flaxseed Oil Attenuates Intestinal Damage by Regulating Ferroptosis Signaling Pathway Following LPS Challenge in Piglets

SCOPE

Ferroptosis has been demonstrated to play an important role in various tissue injuries and diseases. Flaxseed oil (FO) has been proven to have benefits for intestinal health. This study aims to explore whether FO relieved lipopolysaccharide (LPS)-induced intestinal injury through modulating ferroptosis signaling pathway.

METHODS AND RESULTS

A total of 120 weaned piglets are fed diets with 3% soybean oil (SO) or 3% FO for 4 weeks. At the end of the trial, 24 piglets selected from two dietary treatment groups are used in a 2 × 2 factorial design with oil treatment (3% SO versus 3% FO) and LPS challenge (saline versus LPS). At 4 h postinjection with LPS, 24 piglets are slaughtered and intestinal samples are collected. FO improves growth performance of pigs. After LPS treatment, FO mitigates intestinal morphological damage and functional damage. Notably, FO reverses the typical ultra-morphology and biochemical indexes of ferroptosis involving glutathione, malondialdehyde, and 4-hydroxynonenal contents. Mechanistically, FO ameliorates the changes on mRNA or protein abundance of key ferroptosis signals including transferrin receptor protein 1 (TFR1), recombinant iron responsive element binding protein 2 (IREB2), FTL, HSPB1, ferritin heavy chain 1 (FTH1), ferroportin 1 (FPN1), SLC7A11, solute carrier family 3 member 2 (SLC3A2), glutathione peroxidase 4 (GPX4), and arachidonate-15-lipoxygenase (ALOX15).

CONCLUSIONS

FO improves growth performance and mitigates intestinal structural and functional damage, which is involved in regulating ferroptosis signaling pathway.

Novel mechanism by which extracellular vesicles derived from Lactobacillus murinus alleviates deoxynivalenol-induced intestinal barrier disruption

Deoxynivalenol (DON) is a common environmental pollutant that poses a serious health risk to humans worldwide. This study was aim to explore whether gut microbiota is involved in DON-induced intestinal toxicity as well as to reveal effect of probiotics derived from gut microbiota in protecting intestinal barrier and to elucidate mechanism. We found that DON caused disturbed gut microbiota, particularly Lactobacillus murinus (L. murinus) deficiency. DON enhanced M1 macrophage polarization and decreased tight junction protein expression. Microbiota transplantation experiments showed that transfer of DON-disrupted microbiota to healthy mice resulted in delivery of DON-induced intestinal toxicity. Besides, DON lost its damaging effect on macrophage and intestinal barrier in antibiotic-treated mice. Further intervention experiments revealed that L. murinus induce macrophage conversion from M1 to M2 phenotype through secreted extracellular vesicles (EVs) to alleviate DON-induced intestinal barrier disruption. Mechanistically, EVs activate TLR2 to promote M2 macrophage polarization and release IL-10, which in turn enhances intestinal barrier function. Upon successful translation of its efficacy into clinical practice, EVs created from L. murinus could be a novel possible treatment strategy for DON-induced gut disease.

Effects of extracted oil of fermented Tartary buckwheat on lipid-lowering, inflammation modulation, and gut microbial regulation in mice

This study investigated the composition of Tartary buckwheat oil fermented by Monascus purpureus and extracted under supercritical CO2 conditions (FTBO) and evaluated its effects on lipid-lowering, inflammation modulation, and gut microbial regulation in mice that were fed a high-fat diet (MOD). Compared with the raw oil (TBO), the γ-oryzanol content reached 27.09 mg g-1; the monounsaturated fatty acid (MUFA) content (such as oleic acid and palmitic acid) was elevated; and the antioxidant capacities of DPPH, ABTS, and hydroxyl were improved in FTBO (p < 0.0001). Then, supplementation with FTBO had a remarkable effect on reducing the body weight and visceral obesity as well as alleviating hyperglycemia, dyslipidemia, inflammatory reactions, and liver damage. The TC, TG, and LDL-C levels in the liver and plasma were reduced, and the HDL-C levels in the liver were increased (p < 0.05). In particular, the high-dose group (FTBOH) exhibited the most significant effect on reducing the pro-inflammatory cytokines ET, TNF-α, IL-1β, and IL-6 in the liver, which were 18.85, 570.12, 50.47, and 26.22 pg mL-1, respectively (p < 0.05). Moreover, FTBO reversed intestinal disorders and increased the intestinal microbial diversity and richness. The relative abundance of beneficial bacteria, such as Bifidobacterium, Lactobacillus, Limosilactobacillus, and Lachnospiraceae_UCG-006, were increased, and the relative abundance of the harmful bacteria Staphylococcus and Lachnoclostridium were reduced. In summary, FTBO has potential applications as a dietary supplement or dietary modifier in lowering blood lipids, modulating immune activity, and reversing intestinal disorders. This study provides reference guidance for the subsequent industrialization and development of Tartary buckwheat, the extension of the industrial chain, the development of new products, and the extraction of functional components.