Soybean Agglutinin Alters the Gut Microbiota and Promotes Inflammation in Lupus-Prone MRL/lpr Mice.

BACKGROUND: Certain foods can trigger flares in patients with systemic lupus erythematosus. Lectins in edible plants have been reported to increase inflammation. OBJECTIVE: This study aimed to determine the effects of 1-time intake of soybean agglutinin (SBA) on the gut microbiota and immune response in lupus-prone MRL/MpJ (MRL)/lpr mice. METHODS: MRL/MpJ-Faslpr/J (MRL/lpr) and MRL mice were randomly assigned into 4 groups (8 mice/group): MRL mice + phosphate-buffered saline (PBS) (CON), MRL mice + SBA (CS), MRL/lpr mice + PBS (LPR), and MRL/lpr + SBA (LS). PBS and SBA were orally administered at 16 wk of age, and all mice were killed 24 h after oral challenge. The disease phenotype, levels of proinflammatory cytokines, and composition of the intestinal microbiota were determined. RESULTS: Interferon-gamma (IFN-γ) in the serum was significantly higher, whereas the level of serum IL-10 was significantly lower in LS mice than in LPR mice [fold change (FC) = 1.31 and FC = 0.36, respectively]. The expression levels of IL-6 and TNF-α in the spleen of LS mice were significantly higher than those in LPR mice (FC = 1.66 and FC = 1.96, respectively). The expression levels of IL-6, TNF-α, and IL-1ß in the kidney were also significantly higher in LS mice than in LPR mice (FC = 2.89, FC = 3.78, and FC = 2.02, respectively). The relative abundances of Erysipelotrichaceae and Turicibacter in LS mice were significantly higher than those in LPR mice (FC = 1.73 and FC = 1.74, respectively). The percentage of Breg cells in the mesenteric lymph nodes was significantly lower in LS mice than in LPR mice (FC = 0.53) (P < 0.05). No change was found between SBA treatment or not in the control (MRL) mice. CONCLUSIONS: One-time intake of SBA can promote the secretion of proinflammatory cytokines, downregulate Breg cells, and alter the intestinal flora in MRL/lpr mice within 24 h of oral challenge, which may contribute to exacerbation of lupus.

Effect of Aspergillus flavus contamination on the fungal community succession, mycotoxin production and storage quality of maize kernels at various temperatures.

Aspergillus flavus, a notorious saprobe and opportunistic plant pathogen, alters mycotoxin contamination and biochemical components in maize kernels during processing and storage, thereby reducing the possibilities of maize end use and compromising food safety. This study explored changes in mycotoxin production, fungal community succession and biochemical components in maize kernels stored at 20, 25 and 30 °C, exposed to A. flavus. Results showed that aflatoxin B1 concentration increased over time, reaching 4.88 µg/kg at 20 °C, 167.23 µg/kg at 25 °C and 349.64 µg/kg at 30 °C after 15 days of storage, whereas the zearalenone production was characterized by an increase followed by a decrease. Correspondingly, the number of molds gradually increased and reached a stable stage after 10 days. High-throughput sequencing of the internal transcribed spacer (ITS) revealed that Eurotium dominated the fungal communities, with A. flavus reaching maximum abundance in maize kernels stored at 30 °C for 15 days. Correlation analysis indicated that the relative abundance of A. flavus was significantly negatively correlated with the content of zein and moisture (P < 0.05). Moreover, the wet milling process of maize effectively eliminated the concentration of aflatoxin B1 and zearalenone from the starch. Pasting temperature and setback value of starch decreased while peak viscosity, final viscosity and breakdown value increased with storage. These findings indicate that interactions between the epiphytic fungal community and A. flavus at elevated storage temperatures aggravate both maize quality deterioration and mycotoxin contamination. Furthermore, they have a discernible impact on the pasting properties of starch. This insight informs strategies to control fungal infections during maize processing and storage.

Nlrp12 deficiency alters gut microbiota and ameliorates Faslpr -mediated systemic autoimmunity in male mice.

NLRP12 has dual roles in shaping inflammation. We hypothesized that NLRP12 would modulate myeloid cells and T cell function to control systemic autoimmunity. Contrary to our hypothesis, the deficiency of Nlrp12 in autoimmune-prone B6.Faslpr/lpr mice ameliorated autoimmunity in males but not females. Nlrp12 deficiency dampened B cell terminal differentiation, germinal center reaction, and survival of autoreactive B cells leading to decreased production of autoantibodies and reduced renal deposition of IgG and complement C3. In parallel, Nlrp12 deficiency reduced the expansion of potentially pathogenic T cells, including double-negative T cells and T follicular helper cells. Furthermore, reduced pro-inflammatory innate immunity was observed, where the gene deletion decreased in-vivo expansion of splenic macrophages and mitigated ex-vivo responses of bone marrow-derived macrophages and dendritic cells to LPS stimulation. Interestingly, Nlrp12 deficiency altered the diversity and composition of fecal microbiota in both male and female B6/lpr mice. Notably, however, Nlrp12 deficiency significantly modulated small intestinal microbiota only in male mice, suggesting that the sex differences in disease phenotype might be gut microbiota-dependent. Together, these results suggest a potential pathogenic role of NLRP12 in promoting systemic autoimmunity in males. Future studies will investigate sex-based mechanisms through which NLRP12 differentially modulates autoimmune outcomes.

Gut microbiota and growth performance of offspring are influenced by wet nurse in pigs using cross-fostering trial.

BACKGROUND: Nursing mom can regulate the gut microbiome succession in offspring. However, it remains unclear whether these effects are long-term and what effect it has on the growth performance of piglets. This study aimed to develop a cross-fostering model of piglets and investigate the effect of maternal environment on gut microbiota, even the growth performance of the offspring, and if this effect could be maintained in the long term. RESULTS: Four groups of piglets were generated as follows (n = 12): Duroc piglets nursed by their birth mom (Dd) or Yorkshire sows (Yd), Yorkshire piglets nursed by Duroc sows (Dy) or their birth mom (Yy). The study found that cross-fostering improved the growth performance of piglets for a long time. The gut microbiota of piglets was mainly determined by the breeds of nursing moms before weaning, and it was more and more influenced by their breeds after weaning, but the influence of birth mom breeds still existed. The linear discriminant analysis (LDA) effect size (LEfSe) analysis and Spearman correlation analysis showed that Sutterella, Butyricimonas and Alistipes, which were affected by nursing mom before weaning, had a strong positive correlation with the growth performance of piglets before weaning. Candidatus_Soleaferrea and Treponema, which were affected by both nursing mom and piglet breed after weaning, were significantly negatively correlated with the growth performance of piglets long after weaning. CONCLUSION: Our results revealed that both the breeds of piglets and their birth moms influence the gut microbiota of piglets for a long time, even after weaning. Additionally, this effect might be related to the growth performance of piglets. © 2022 Society of Chemical Industry.

Ileum tissue single-cell mRNA sequencing elucidates the cellular architecture of pathophysiological changes associated with weaning in piglets.

BACKGROUND: In mammals, transitioning from sole milk uptake to the intake of solid feed results in dramatic developmental changes in intestinal function and immunological status. In fact, weaning stress is often accompanied by intestinal inflammatory processes. To develop effective intervention strategies, it is necessary to characterize the developmental pattern and immune response that occurs on weaning, as we have done in this study for piglets. RESULTS: To comprehensively delineate cell heterogeneity in ileum tissues and the underlying mechanisms in weaning-induced intestinal inflammation of piglets, we have analyzed the transcriptomes of 42,149 cells from ileum mucosa of normally suckling and post-weaned piglets. There were 31 cell subtypes including epithelial, stromal, and immune cells. A bifurcating trajectory was inferred to separate secretory and absorptive lineages. Integrated cross-species datasets showed well-conserved cellular architectures and transcription signatures between human and pig. Comparative analyses of cellular components, cell-cell communications, and molecular states revealed that T cell subpopulations were significantly altered in weaned piglets. We found that T helper (Th) 17 functional plasticity across changes in the cytokine milieu and the enrichment of granzyme B (GZMB)-expressing cytotoxic T cells potentially exacerbate mucosal inflammation via mitochondrial dysfunction in epithelial cells. CONCLUSIONS: Our work has elucidated the single-cell molecular characteristics of the piglet ileum before and after weaning. We have provided an atlas that portrays the landscape of the intestinal pathophysiological inflammatory process associated with weaning, finding a level of conservation between human and pig that support the use of piglets as a model for human infants.

Lactic Acid Bacteria Mixture Isolated From Wild Pig Alleviated the Gut Inflammation of Mice Challenged by Escherichia coli.

Wild pigs usually showed high tolerance and resistance to several diseases in the wild environment, suggesting that the gut bacteria of wild pigs could be a good source for discovering potential probiotic strains. In our study, wild pig feces were sequenced and showed a higher relative abundance of the genus Lactobacillus (43.61% vs. 2.01%) than that in the domestic pig. A total of 11 lactic acid bacteria (LAB) strains including two L. rhamnosus, six L. mucosae, one L. fermentum, one L. delbrueckii, and one Enterococcus faecalis species were isolated. To investigate the synergistic effects of mixed probiotics strains, the mixture of 11 LAB strains from an intestinal ecology system was orally administrated in mice for 3 weeks, then the mice were challenged with Escherichia coli ATCC 25922 (2 × 109 CFU) and euthanized after challenge. Mice administrated with LAB strains showed higher (p < 0.05) LAB counts in feces and ileum. Moreover, alterations of specific bacterial genera occurred, including the higher (p < 0.05) relative abundance of Butyricicoccus and Clostridium IV and the lower (p < 0.05) abundance of Enterorhabdus in mice fed with mixed LAB strains. Mice challenged with Escherichia coli showed vacuolization of the liver, lower GSH in serum, and lower villus to the crypt proportion and Claudin-3 level in the gut. In contrast, administration of mixed LAB strains attenuated inflammation of the liver and gut, especially the lowered IL-6 and IL-1ß levels (p < 0.05) in the gut. Our study highlighted the importance of gut bacterial diversity and the immunomodulation effects of LAB strains mixture from wild pig in gut health.

Phenotypic Drift in Lupus-Prone MRL/lpr Mice: Potential Roles of MicroRNAs and Gut Microbiota.

MRL/lpr mice have been extensively used as a murine model of lupus. Disease progression in MRL/lpr mice can differ among animal facilities, suggesting a role for environmental factors. We noted a phenotypic drift of our in-house colony, which was the progeny of mice obtained from The Jackson Laboratory (JAX; stocking number 000485), that involved attenuated glomerulonephritis, increased splenomegaly, and reduced lymphadenopathy. To validate our in-house mice as a model of lupus, we compared these mice with those newly obtained from JAX, which were confirmed to be genetically identical to our in-house mice. Surprisingly, the new JAX mice exhibited a similar phenotypic drift, most notably the attenuation of glomerulonephritis. Interestingly, our in-house colony differed from JAX mice in body weight and kidney size (both sexes), as well as in splenic size, germinal center formation, and level of anti-dsDNA auto-IgG in the circulation (male only). In addition, we noted differential expression of microRNA (miR)-21 and miR-183 that might explain the splenic differences in males. Furthermore, the composition of gut microbiota was different between in-house and new JAX mice at early time points, which might explain some of the renal differences (e.g., kidney size). However, we could not identify the reason for attenuated glomerulonephritis, a shared phenotypic drift between the two colonies. It is likely that this was due to certain changes of environmental factors present in both JAX and our facilities. Taken together, these results suggest a significant phenotypic drift in MRL/lpr mice in both colonies that may require strain recovery from cryopreservation.

L. reuteri ZJ617 inhibits inflammatory and autophagy signaling pathways in gut-liver axis in piglet induced by lipopolysaccharide.

BACKGROUND: This study investigated the protective effects of L. reuteri ZJ617 on intestinal and liver injury and the underlying mechanisms in modulating inflammatory, autophagy, and apoptosis signaling pathways in a piglet challenged with lipopolysaccharide (LPS). METHODS: Duroc × Landrace × Large White piglets were assigned to 3 groups (n = 6/group): control (CON) and LPS groups received oral phosphate-buffered saline for 2 weeks before intraperitoneal injection (i.p.) of physiological saline or LPS (25 µg/kg body weight), respectively, while the ZJ617 + LPS group was orally inoculated with ZJ617 for 2 weeks before i.p. of LPS. Piglets were sacrificed 4 h after LPS injection to determine intestinal integrity, serum biochemical parameters, inflammatory signaling involved in molecular and liver injury pathways. RESULTS: Compared with controls, LPS stimulation significantly increased intestinal phosphorylated-p38 MAPK, phosphorylated-ERK and JNK protein levels and decreased IκBα protein expression, while serum LPS, TNF-α, and IL-6 concentrations (P < 0.05) increased. ZJ617 pretreatment significantly countered the effects induced by LPS alone, with the exception of p-JNK protein levels. Compared with controls, LPS stimulation significantly increased LC3, Atg5, and Beclin-1 protein expression (P < 0.05) but decreased ZO-1, claudin-3, and occludin protein expression (P < 0.05) and increased serum DAO and D-xylose levels, effects that were all countered by ZJ617 pretreatment. LPS induced significantly higher hepatic LC3, Atg5, Beclin-1, SOD-2, and Bax protein expression (P < 0.05) and lower hepatic total bile acid (TBA) levels (P < 0.05) compared with controls. ZJ617 pretreatment significantly decreased hepatic Beclin-1, SOD2, and Bax protein expression (P < 0.05) and showed a tendency to decrease hepatic TBA (P = 0.0743) induced by LPS treatment. Pretreatment of ZJ617 before LPS injection induced the production of 5 significant metabolites in the intestinal contents: capric acid, isoleucine 1TMS, glycerol-1-phosphate byproduct, linoleic acid, alanine-alanine (P < 0.05). CONCLUSIONS: These results demonstrated that ZJ617 pretreatment alleviated LPS-induced intestinal tight junction protein destruction, and intestinal and hepatic inflammatory and autophagy signal activation in the piglets.

Encapsulated Mixture of Methyl Salicylate and Tributyrin Modulates Intestinal Microbiota and Improves Growth Performance of Weaned Piglets.

Tributyrin and essential oils have been used as alternatives to antimicrobials to improve gut health and growth performance in piglets. This study was to evaluate the effects of a dietary supplement with two encapsulated products containing different combinations of tributyrin with oregano or with methyl salicylate on growth performance, serum biochemical parameters related to the physiological status, intestinal microbiota and metabolites of piglets. A total of 108 weaned crossbred piglets (Yorkshire × Landrace, 21 ± 1 d, 8.21 ± 0.04 kg) were randomly divided into three groups. Piglets were fed with one of the following diets for 5 weeks: a basal diet as the control (CON); the control diet supplemented with an encapsulated mixture containing 30% of methyl salicylate and tributyrin at a dosage of 3 kg/t (CMT); and the control diet supplemented with an encapsulated mixture containing 30% of oregano oil and tributyrin at a dosage of 3 kg/t (COT). At the end of the feeding trial, six piglets from each group were slaughtered to collect blood and gut samples for physiological status and gut microbiological analysis. The study found that the CMT group was larger in feed intake (FI) (p < 0.05), average daily gain (ADG) (p = 0.09), total protein (TP), albumin (ALB), glutathione peroxidase (GSH-PX) (p < 0.05), blood total antioxidant capacity (T-AOC) (p < 0.05), and crypt depth in the ileum (p < 0.05) compared with the CON group. The genus abundance of Tissierella and Campylobacter in the CMT group was significantly decreased compared with the CON group. The CMT group also resulted in significantly higher activity in amino acid metabolism and arginine biosynthesis compared with the CON group. The COT group was larger in T-AOC, and the genus abundance of Streptophyta and Chlamydia was significantly increased in the ileum compared with the CON group. Data analysis found a significantly high correlation between the genus abundance of Chlamydia and that of Campylobacter in the ileum. The genus abundance of Campylobacter was also positively correlated with the sorbitol level. In general, the results indicated that the supplementation of both encapsulated mixtures in diet of weaned piglets could improve the animal blood antioxidant capacity. Additionally, the encapsulated mixture of methyl salicylate plus tributyrin improved the growth performance and resulted in certain corresponding changes in nutrient metabolism and in the genus abundance of ileum microbial community.

Regulation of neonatal IgA production by the maternal microbiota.

Infants are prone to enteric infections due to an underdeveloped immune system. The maternal microbiota, through shaping the neonatal microbiota, helps establish a strong immune system in infants. We and others have observed the phenomenon of enhanced early neonatal immunoglobulin A (IgA) production in preweaning immunocompetent mice nursed by immunodeficient dams. Here, we show that this enhancement of IgA in neonates results from maternally derived microbiota. In addition, we have found that the neonatal IgA production can be induced by Lactobacillus reuteri, which is enriched in the milk of immunodeficient dams. Moreover, we show that while the production of neonatal IgA is dependent on neonatal T cells, the immunodeficient maternal microbiota-mediated enhancement of neonatal IgA has a T cell-independent component. Indeed, this enhancement may be dependent on type 3 innate lymphoid cells in the neonatal small intestinal lamina propria. Interestingly, maternal microbiota-induced neonatal IgA does not cross-react with common enteric pathogens. Future investigations will determine the functional consequences of having this extra IgA.

Gut Microbiota and Bacterial DNA Suppress Autoimmunity by Stimulating Regulatory B Cells in a Murine Model of Lupus.

Autoimmune diseases, such as systemic lupus erythematosus, are characterized by excessive inflammation in response to self-antigens. Loss of appropriate immunoregulatory mechanisms contribute to disease exacerbation. We previously showed the suppressive effect of vancomycin treatment during the "active-disease" stage of lupus. In this study, we sought to understand the effect of the same treatment given before disease onset. To develop a model in which to test the regulatory role of the gut microbiota in modifying autoimmunity, we treated lupus-prone mice with vancomycin in the period before disease development (3-8 weeks of age). We found that administration of vancomycin to female MRL/lpr mice early, only during the pre-disease period but not from 3 to 15 weeks of age, led to disease exacerbation. Early vancomycin administration also reduced splenic regulatory B (Breg) cell numbers, as well as reduced circulating IL-10 and IL-35 in 8-week old mice. Further, we found that during the pre-disease period, administration of activated IL-10 producing Breg cells to mice treated with vancomycin suppressed lupus initiation, and that bacterial DNA from the gut microbiota was an inducer of Breg function. Oral gavage of bacterial DNA to mice treated with vancomycin increased Breg cells in the spleen and mesenteric lymph node at 8 weeks of age and reduced autoimmune disease severity at 15 weeks. This work suggests that a form of oral tolerance induced by bacterial DNA-mediated expansion of Breg cells suppress disease onset in the autoimmune-prone MRL/lpr mouse model. Future studies are warranted to further define the mechanism behind bacterial DNA promoting Breg cells.

Lactobacillus rhamnosus GG Attenuates Lipopolysaccharide-Induced Inflammation and Barrier Dysfunction by Regulating MAPK/NF-κB Signaling and Modulating Metabolome in the Piglet Intestine.

BACKGROUND: Probiotic Lactobacillius rhamnosus GG (LGG) shows beneficial immunomodulation on cultured cell lines in vitro and in mouse models. OBJECTIVE: The aim was to investigate the effects of LGG on intestinal injury and the underlying mechanisms by elucidating inflammatory signaling pathways and metabolomic response to LPS stimulation in the piglet intestine. METHODS: Piglets (Duroc × Landrace × Large White, including males and female; 8.6 ± 1.1 kg) aged 28 d were assigned to 3 groups (n = 6/group): oral inoculation with PBS for 2 wk before intraperitoneal injection of physiological saline [control (CON)] or LPS (25 µg/kg body weight; LPS) or oral inoculation with LGG for 2 wk before intraperitoneal injection of LPS (LGG+LPS). Piglets were killed 4 h after LPS injection. Systemic inflammation, intestinal integrity, inflammation signals, and metabolomic characteristics in the intestine were determined. RESULTS: Compared with CON, LPS stimulation significantly decreased ileal zonula occludens 1 (ZO-1; 44%), claudin-3 (44%), and occludin (41%) expression; increased serum diamineoxidase (73%), D-xylose (19%), TNF-α (43%), and IL-6 (55%) concentrations; induced p38 mitogen-activated protein kinase (p38 MAPK; 85%), extracellular signal-regulated kinase (ERK; 96%), and NF-κB p65 phosphorylation (37%) (P < 0.05). Compared with LPS stimulation alone, LGG pretreatment significantly enhanced the intestinal barrier by upregulating expressions of tight junction proteins (ZO-1, 73%; claudin-3, 55%; occludin, 67%), thereby decreasing serum diamineoxidase (26%) and D-xylose (28%) concentrations, and also reduced serum TNF-α expression (16%) and ileal p38 MAPK (79%), ERK (43%) and NF-κB p65 (37%) phosphorylation levels (P < 0.05). Metabolomic analysis showed clear separation between each group. The concentrations of caprylic acid [fold-change (FC) = 2.39], 1-mono-olein (FC = 2.68), erythritol (FC = 4.62), and ethanolamine (FC = 4.47) significantly increased in the intestine of LGG + LPS piglets compared with the LPS group (P < 0.05). CONCLUSIONS: These data suggest that LGG alleviates gut inflammation, improves intestinal barrier function, and modulates the metabolite profile of piglets challenged with LPS. This trial was registered at the Zhejiang University (http://www.lac.zju.edu.cn) as ZJU20170529.

Parenterally Administered P24-VP8* Nanoparticle Vaccine Conferred Strong Protection against Rotavirus Diarrhea and Virus Shedding in Gnotobiotic Pigs.

Current live rotavirus vaccines are costly with increased risk of intussusception due to vaccine replication in the gut of vaccinated children. New vaccines with improved safety and cost-effectiveness are needed. In this study, we assessed the immunogenicity and protective efficacy of a novel P24-VP8* nanoparticle vaccine using the gnotobiotic (Gn) pig model of human rotavirus infection and disease. Three doses of P24-VP8* (200 µg/dose) intramuscular vaccine with Al(OH)3 adjuvant (600 µg) conferred significant protection against infection and diarrhea after challenge with virulent Wa strain rotavirus. This was indicated by the significant reduction in the mean duration of diarrhea, virus shedding in feces, and significantly lower fecal cumulative consistency scores in post-challenge day (PCD) 1-7 among vaccinated pigs compared to the mock immunized controls. The P24-VP8* vaccine was highly immunogenic in Gn pigs. It induced strong VP8*-specific serum IgG and Wa-specific virus-neutralizing antibody responses from post-inoculation day 21 to PCD 7, but did not induce serum or intestinal IgA antibody responses or a strong effector T cell response, which are consistent with the immunization route, the adjuvant used, and the nature of the non-replicating vaccine. The findings are highly translatable and thus will facilitate clinical trials of the P24-VP8* nanoparticle vaccine.

Pregnancy and lactation interfere with the response of autoimmunity to modulation of gut microbiota.

BACKGROUND: Dysbiosis of gut microbiota exists in the pathogenesis of many autoimmune diseases, including systemic lupus erythematosus (lupus). Lupus patients who experienced pregnancy usually had more severe disease flares post-delivery. However, the possible role of gut microbiota in the link between pregnancy and exacerbation of lupus remains to be explored. RESULTS: In the classical lupus mouse model MRL/lpr, we compared the structures of gut microbiota in pregnant and lactating individuals vs. age-matched naïve mice. Consistent with studies on non-lupus mice, both pregnancy and lactation significantly changed the composition and diversity of gut microbiota. Strikingly, modulation of gut microbiota using the same strategy resulted in different disease outcomes in postpartum (abbreviated as "PP," meaning that the mice had undergone pregnancy and lactation) vs. control (naïve; i.e., without pregnancy or lactation) MRL/lpr females; while vancomycin treatment attenuated lupus in naïve mice, it did not do so, or even exacerbated lupus, in PP mice. Lactobacillus animalis flourished in the gut upon vancomycin treatment, and direct administration of L. animalis via oral gavage recapitulated the differential effects of vancomycin in PP vs. control mice. An enzyme called indoleamine 2,3-dioxygenase was significantly inhibited by L. animalis; however, this inhibition was only apparent in PP mice, which explained, at least partially, the lack of beneficial response to vancomycin in these mice. The differential production of immunosuppressive IL-10 and proinflammatory IFNγ in PP vs. control mice further explained why the disease phenotypes varied between the two types of mice bearing the same gut microbiota remodeling strategy. CONCLUSIONS: These results suggest that pregnancy and lactation interfere with the response of autoimmunity to modulation of gut microbiota. Further studies are necessary to better understand the complex relationship between pregnancy and lupus.

Lactobacillus reuteri ZJ617 Culture Supernatant Attenuates Acute Liver Injury Induced in Mice by Lipopolysaccharide.

BACKGROUND: Lactobacillus rhamnosus GG culture supernatant (LGGs) promotes intestinal integrity and ameliorates acute liver injury induced by alcohol in mice. OBJECTIVES: The aim of this study was to investigate the protective effects and molecular mechanisms of Lactobacillus reuteri ZJ617 culture supernatant (ZJ617s) on acute liver injury induced by lipopolysaccharide (LPS) in mice. METHODS: Male C57BL/6 mice (20 ± 2 g, 8 wk old) were randomly divided into 4 groups (6 mice/group): oral inoculation with phosphate-buffered saline (control), intraperitoneal injection of LPS (10 mg/kg body weight) (LPS), oral inoculation with ZJ617s 2 wk before intraperitoneal injection of LPS (ZJ617s + LPS), or oral inoculation with LGGs 2 wk before intraperitoneal injection of LPS (LGGs + LPS). Systemic inflammation, intestinal integrity, biomarkers of hepatic function, autophagy, and apoptosis signals in the liver were determined. RESULTS: Twenty-four hours after LPS injection, the activities of serum alanine transaminase and aspartate transaminase were 32.2% and 30.3% lower in the ZJ617s + LPS group compared with the LPS group, respectively (P < 0.05). The ZJ617s + LPS group exhibited higher intestinal expression of claudin 3 (62.5%), occludin (60.1%), and zonula occludens 1 (60.5%) compared with the LPS group (P < 0.05). The concentrations of hepatic interleukin-6 and tumor necrosis factor-α were 21.4% and 27.3% lower in the ZJ617s + LPS group compared with the LPS group, respectively (P < 0.05). However, the concentration of interleukin-10 was 22.2% higher in the ZJ617s + LPS group. LPS increased the expression of Toll-like receptor 4 (TLR4; by 50.5%), phosphorylation p38 mitogen-activated protein kinase (p38MAPK; by 57.1%), extracellular signal-regulated kinase (by 77.8%), c-Jun N-terminal kinase (by 42.9%), and nuclear factor-κB (NF-κB; by 36.0%) compared with the control group. Supplementation with ZJ617s or LGGs ameliorated these effects (P < 0.05). Moreover, the hepatic expression of active caspase-3 and microtubule-associated protein 1 light chain 3 II was 23.8% and 28.6% lower in the ZJ617s + LPS group compared with the LPS group, respectively (P < 0.05). CONCLUSIONS: ZJ617s exerts beneficial effects on the mouse liver through suppression of hepatic TLR4/MAPK/NF-κB activation, apoptosis, and autophagy. This trial was registered at Zhejiang University (http://www.lac.zju.edu.cn) as NO.ZJU20170529.