Lactobacillus sakei K17, an inducer of IL-10 expression in antigen-presenting cells, attenuates TNBS-induced colitis in mice.

To understand the anti-colitic effects of probiotics that up-regulate interleukin (IL)-10 expression in dendritic cells (DCs) and macrophages, we isolated Lactobacillus sakei K17, which potently induced IL-10 expression in DCs and peritoneal macrophages in vitro, among the lactic acid bacteria strains collected from kimchi and investigated its anti-inflammatory effect in mice with 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. Oral administration of K17 (2 × 109 CFU·mouse-1·day-1) in mice with TNBS-induced colitis suppressed colon shortening and myeloperoxidase activity, as well as infiltration of CD86+ cells into the colon. Treatment with K17 also increased TNBS-suppressed expression of tight junction proteins and IL-10, but inhibited activation of nuclear factor-kappaB (NF-κB) and mitogen-activated protein kinases and expression of tumor necrosis factor α and IL-17. Its effect was comparable with that of sulfasalazine (50 mg/kg), a positive commercial ant-colitic drug. Furthermore, treatment with K17 (1 × 105 CFU/mL) potently inhibited lipopolysaccharide (LPS)-stimulated NF-κB activation in DCs and peritoneal macrophages and restored tight junction protein expression in LPS-stimulated Caco-2 cells. These findings suggest that Lactobacillus sakei K17 may ameliorate colitis by up-regulating the expression of IL-10 and tight junction proteins and inhibiting NF-κB activation.

Lactobacillus pentosus var. plantarum C29 ameliorates memory impairment and inflammaging in a D-galactose-induced accelerated aging mouse model.

Aging is associated with Alzheimer's disease (AD), cardiovascular disease and cancer. Oxidative stress is considered as a major factor that accelerates the aging process. To understand the ability of lactic acid bacteria to ameliorate memory impairment caused by aging, we investigated the effect of Lactobacillus pentosus var. plantarum (C29), which is known to protect against scopolamine-induced memory impairment, on oxidative stress (D-galactose)-induced memory impairment in mice. D-Galactose was subcutaneously injected to 20-week old male C57BL/6J mice for 10 weeks, with oral administration of C29 for the final 5 weeks. Excessive intake of D-galactose not only impaired memory, which was indicated by passive avoidance, Y-maze, and Morris water-maze tasks, but also reduced the expression of brain-derived neurotrophic factor (BDNF) and hippocampal doublecortin (DCX) and the activation of cAMP response element-binding protein (CREB). C29 treatment ameliorated D-galactose-induced memory impairment and reversed the suppression of BDNF and DCX expression and CREB activation. Moreover, C29 decreased the expression of a senescence marker p16 and inflammation markers p-p65, p-FOXO3a, cyclooxygenase (COX)-2, and inducible NO synthase (iNOS). C29 treatment inhibited D-galactose-induced expression of M1 polarization markers tumor necrosis factor-α and arginase II, and attenuated the d-galactose-suppressed expression of M2 markers IL-10, arginase I and CD206. Taken together, these findings suggest that C29 may ameliorate memory impairment and M1 macrophage-polarized inflammation caused by aging.

Lactobacillus casei HY7213 ameliorates cyclophosphamide-induced immunosuppression in mice by activating NK, cytotoxic T cells and macrophages.

Lactic acid bacteria (LAB) have recently attracted considerable attention as treatment options for immune diseases, the incidence of which has been increasing worldwide. The ability of tumor necrosis factor-α producing LAB isolated from cheese to inhibit NF-κB activation in lipopolysaccharide (LPS)-stimulated peritoneal macrophages was investigated. Among the tested LAB, Lactobacillus casei HY7213 inhibited NF-κB activation most potently. Therefore, we measured its immunopotentiating effect in cyclophosphamide (CP)-immunosuppressed mice. When HY7213 was orally administered for 5 or 15 d, it reversed the CP immunosuppressant effect by increasing body and spleen weights, blood red and white blood cells levels, and splenocyte and bone marrow cells counts. Treatment with CP in mice markedly reduced concanavalin A (ConA)-induced T cell proliferation to 54% compared to the normal group. Oral administration of HY7213 in CP-immunosuppressed mice reversed that value to 95% of the normal group on day 15. Furthermore, oral administration of HY7213 to CP-treated mice significantly enhanced the expression of IL-2 and IFN-γ in ConA-induced splenic cytotoxic T cells, restored the CP-impaired phagocytosis of macrophage, and increased the cytotoxicity of natural killer (NK) and cytotoxic T cells derived from spleen and bone marrow against YAC-1. Based on these findings, we suggest that HY7213 may promote the recovery of immunosuppression caused by chemotherapeutic agents, such as CP, by activating NK cells, cytotoxic T cells and macrophages.

Lactobacillus gasseri NK109 and Its Supplement Alleviate Cognitive Impairment in Mice by Modulating NF-κB Activation, BDNF Expression, and Gut Microbiota Composition.

Aging-related gut microbiota dysbiosis initiates gut inflammation and microbiota dysbiosis, which induce the occurrence of psychiatric disorders including dementia. The alleviation of gut microbiota dysbiosis by probiotics is suggested to be able to alleviate psychiatric disorders including cognitive impairment (CI). Therefore, to understand how probiotics could alleviate CI, we examined the effects of anti-inflammatory Lactobacillus gasseri NK109 and its supplement (NS, mixture of NK109 and soybean embryo ethanol extract) on cognitive function in aged (Ag), 5XFAD transgenic (Tg), or mildly cognition-impaired adult fecal microbiota (MCF)-transplanted mice. Oral administration of NK109 or NS decreased CI-like behaviors in Ag mice. Their treatments suppressed TNF-α and p16 expression and NF-κB-activated cell populations in the hippocampus and colon, while BDNF expression was induced. Moreover, they partially shifted the ß-diversity of gut microbiota in Ag mice to those of young mice: they decreased Bifidobacteriaceae, Lactobacillaceae, and Helicobacteriaceae populations and increased Rikenellaceae and Prevotellaceae populations. Oral administration of NK109 or NS also reduced CI-like behaviors in Tg mice. Their treatments induced BDNF expression in the hippocampus, decreased hippocampal TNF-α and Aß expression and hippocampal and colonic NF-κB-activated cell populations. NK109 and NS partially shifted the ß-diversity of gut microbiota in Tg mice: they decreased Muribaculaceae and Rhodospiraceae populations and increased Helicobacteriaceae population. Oral administration of NK109 or NS decreased MCF transplantation-induced CI-like behaviors in mice. NK109 and NS increased hippocampal BDNF expression, while hippocampal and colonic TNF-α expression and NF-κB-activated cell populations decreased. These findings suggest that dementia can fluctuate the gut microbiota composition and NK109 and its supplement NS can alleviate CI with systemic inflammation by inducing BDNF expression and suppressing NF-κB activation and gut microbiota dysbiosis.

Rice yogurt with various beans fermented by lactic acid bacteria from kimchi.

In this study, the rice yogurt with various beans was developed using a mixture of rice saccharification solution as an artificial sweetener substitute and bean milk as a milk substitute. Rice yogurt was fermented with lactic acid bacteria isolated from kimchi. The lactic acid bacteria count in rice yogurt with various beans had the highest range of 9.37- 9.54 log CFU/g at 12 h fermentation. Also, at 12 h fermentation, pH ranged from 4.05 to 4.20. Rice yogurt with seoritae had the highest brix (15.52°Bx) and DPPH radical scavenging activity (41.86%). In the sensory evaluation, rice yogurt with seoritae received high preference scores in most categories, including flavor, sweet taste, sour taste, mouthfeel and overall preference. These findings suggest that the optimum fermentation time may be 12 h, and rice saccharification solution is an appropriate sugar substitute. Seoritae milk is suitable for the development of rice yogurt with beans.

Anti-scratching behavioral effect of Lactobacillus plantarum PM008 isolated from kimchi in mice.

To isolate antipruritic lactic acid bacteria (LAB) from kimchi, a traditional Korean food, we investigated the interleukin (IL)-4 production-inhibitory effect in the colon of mice for previously isolated LAB. Orally administered Lactobacillus plantarum PM008 potently inhibited the expression of IgE-switching cytokine, IL-4, and of proinflammatory cytokines, IL-1ß and TNF-α, in the colon of mice. Its inhibitory effect was dependent on the dosage and administration period. When PM008 was orally administered to mice, the number of PM008 detected in the intestine and feces by polymerase chain reaction (PCR) and fluorescence in situ hybridization (FISH) methods was dependent on the administration dosage and period. The number of PM008 attached in the intestine was gradually decreased with increasing time after completion of its oral administration. PM008 dose-dependently inhibited the scratching behavior induced by histamine or compound 48/80. PM008 treated at a dose of 1 × 10(10) CFU for 14 days inhibited the histamine- and compound 48/80-induced scratching behaviors by 32.8% and 48.6%, respectively. This inhibitory effect continued, although reduced, at 7 days after stopping the oral administration of PM008 attached in the intestine. Based on these findings, L. plantarum PM008 may improve pruritus by inhibiting IL-4 expression.

DW2009 Elevates the Efficacy of Donepezil against Cognitive Impairment in Mice.

Lactobacillus plantarum C29 and DW2009 (C29-fermented soybean) alleviate cognitive impairment through the modulation of the microbiota-gut-brain axis. Therefore, we examined whether combining donepezil, a well-known acetylcholinesterase inhibitor, with C29 or DW2009 could synergistically alleviate cognitive impairment in mice. Oral administration of donepezil combined with or without C29 (DC) or DW2009 (DD) alleviated lipopolysaccharide (LPS)-induced cognitive impairment-like behaviors more strongly than treatment with each one alone. Their treatments significantly suppressed the NF-κB+/Iba1+ (activated microglia) population, NF-κB activation, and tumor necrosis factor-α and interleukin-1ß expression in the hippocampus, while the brain-derived neurotropic factor (BDNF)+/NeuN+ cell population and BDNF expression increased. Their treatments strongly suppressed LPS-induced colitis. Moreover, they increased the Firmicutes population and decreased the Cyanobacteria population in gut microbiota. Of these, DD most strongly alleviated cognitive impairment, followed by DC. In conclusion, DW2009 may synergistically or additively increase the effect of donepezil against cognitive impairment and colitis by regulating NF-κB-mediated BDNF expression.

Lactobacillus plantarum and Bifidobacterium bifidum alleviate dry eye in mice with exorbital lacrimal gland excision by modulating gut inflammation and microbiota.

In order to understand the efficacy of probiotics against dry eye syndrome, we selected anti-inflammatory probiotics Lactobacillus plantarum NK151 and Bifidobacterium bifidum NK175, which increased the ratio of IL-10 to TNF-α expression, from the human gut bacteria collection and examined their effects on tear secretion and cornea/conjunctiva inflammation in mice with excision of the unilateral exorbital lacrimal gland and 1% atropine and 0.1% benzalkonium chloride solution (ELA)-induced dry eye. Exposure to ELA significantly reduced tear secretion in mice, assessed by the phenol red thread tear test. However, oral gavage of NK151 and/or NK175 significantly increased ELA-suppressed tear secretion, IL-10 expression, and goblet cell population and decreased the ELA-induced corneal fluorescein-staining score, IL-1ß and TNF-α expression in the conjunctiva. They also suppressed ELA-induced myeloperoxidase, IL-1ß, and TNF-α expression. In particular, they increased the ratio of IL-10 to TNF-α expression in the colon. Their treatments increased ELA-induced α-diversity reduction to that of the control group and partially restored ELA-shifted ß-diversity to that of the control group. Oral gavage of NK151 and/or NK175 reduced ELA-induced Verrucomicrobia and Actinobacteria populations at the phylum level. Furthermore, they reduced ELA-induced Bacteroidaceae, Akkemansiaceae, and AC160630_f populations and increased ELA-suppressed Lactobacillaceae and Muribaculaceae populations at the family level. These gut bacteria populations exhibited significant correlation with the tear secretion volume. In conclusion, NK151 and/or NK175 alleviated dry eye by modulating the expression ratio of pro-inflammatory cytokines such as TNF-α and anti-inflammatory cytokines such as IL-10 and gut microbiota composition.

Effects of Red and Fermented Ginseng and Ginsenosides on Allergic Disorders.

Both white ginseng (WG, dried root of Panax sp.) and red ginseng (RG, steamed and dried root of Panax sp.) are reported to exhibit a variety of pharmacological effects such as anticancer, antidiabetic, and neuroprotective activities. These ginsengs contain hydrophilic sugar-conjugated ginsenosides and polysaccharides as the bioactive constituents. When taken orally, their hydrophilic constituents are metabolized into hydrophobic ginsenosides compound K, Rh1, and Rh2 that are absorbable into the blood. These metabolites exhibit the pharmacological effects more strongly than hydrophilic parental constituents. To enforce these metabolites, fermented WG and RG are developed. Moreover, natural products including ginseng are frequently used for the treatment of allergic disorders. Therefore, this review introduces the current knowledge related to the effectiveness of ginseng on allergic disorders including asthma, allergic rhinitis, atopic dermatitis, and pruritus. We discuss how ginseng, its constituents, and its metabolites regulate allergy-related immune responses. We also describe how ginseng controls allergic disorders.

A Probiotic Lactobacillus gasseri Alleviates Escherichia coli-Induced Cognitive Impairment and Depression in Mice by Regulating IL-1ß Expression and Gut Microbiota.

Excessive expression of interleukin (IL)-1ß in the brain causes depression and cognitive dysfunction. Herein, we investigated the effect of Lactobacillus gasseri NK109, which suppressed IL-1ß expression in activated macrophages, on Escherichia coli K1-induced cognitive impairment and depression in mice. Germ-free and specific pathogen-free mice with neuropsychiatric disorders were prepared by oral gavage of K1. NK109 alleviated K1-induced cognition-impaired and depressive behaviors, decreased the expression of IL-1ß and populations of NF-κB+/Iba1+ and IL-1R+ cells, and increased the K1-suppressed population of BDNF+/NeuN+ cells in the hippocampus. However, its effects were partially attenuated by celiac vagotomy. NK109 treatment mitigated K1-induced colitis and gut dysbiosis. Tyndallized NK109, even if lysed, alleviated cognitive impairment and depression. In conclusion, NK109 alleviated neuropsychiatric disorders and colitis by modulating IL-1ß expression, gut microbiota, and vagus nerve-mediated gut-brain signaling.

IL-10 Expression-Inducing Gut Bacteria Alleviate High-Fat Diet-Induced Obesity and Hyperlipidemia in Mice.

In the present study, we examined the effects of interleukin (IL)-10 expression-inducing bacteria Bifidobacterium adolescentis HP1, Lactobacillus mucosae HP2, and Weissella cibaria HP3 on high-fat diet (HFD)-induced obesity and liver steatosis in mice. Oral gavage of HP1, HP2, and HP3 reduced HFD-induced bodyweight gain, triglycerides, and total cholesterol levels in the blood and liver. They also suppressed HFD-induced colitis and the fecal δ,γ-Proteobacteria population. Of the tested bacteria, HP2, which most potently inhibited IL-10 expression, also suppressed HFD-induced bodyweight gain, liver steatosis, and colitis most effectively. These findings suggest that IL-10 expression-inducing gut bacteria can suppress obesity and liver steatosis.

The fermentation characteristics of soy yogurt with different content of d-allulose and sucrose fermented by lactic acid bacteria from Kimchi.

In this study, to understand whether d-allulose, an ultra-low calorie sweetener, was available in soy yogurt fermentation, we isolated Leuconostoc mesenteroides and Lactobacillus plantarum from kimchi and fermented in soymilk at various contents of d-allulose and sucrose. The lactic acid bacteria counts in soy yogurt had the highest range of 9.23-9.49 log CFU/g at 24 h fermentation and then decreased. At 48 h fermentation, the pH showed 4.31 and 4.52 in the samples containing 75% and 100% d-allulose as sweetener. DPPH radical scavenging activity showed a decreasing tendency as the amount of d-allulose increased. Soy yogurt samples containing d-allulose had higher scores in sweet taste, sour taste and overall preference in sensory evaluation. These findings suggest that d-allulose is beneficial for the development of a low calorie soy yogurt.

Fermented red ginseng and ginsenoside Rd alleviate ovalbumin-induced allergic rhinitis in mice by suppressing IgE, interleukin-4, and interleukin-5 expression.

BACKGROUND: To increase the pharmacological effects of red ginseng (RG, the steamed root of Panax ginseng Meyer), RG products modified by heat process or fermentation have been developed. However, the antiallergic effects of RG and modified/fermented RG have not been simultaneously examined. Therefore, we examined the allergic rhinitis (AR)-inhibitory effects of water-extracted RG (wRG), 50% ethanol-extracted RG (eRG), and bifidobacteria-fermented eRG (fRG) in vivo. METHODS: RBL-2H3 cells were stimulated with phorbol 12-myristate-13-acetate/A23187. Mice with AR were prepared by treatment with ovalbumin. Allergic markers IgE, tumor necrosis factor-α, interleukin (IL)-4, and IL-5 were assayed in the blood, bronchoalveolar lavage fluid, nasal mucosa, and colon using enzyme-linked immunosorbent assay. Mast cells, eosinophils, and Th2 cell populations were assayed using a flow cytometer. RESULTS: RG products potently inhibited IL-4 expression in phorbol 12-myristate-13-acetate/A23187-stimulated RBL-2H3 cells. Of tested RG products, fRG most potently inhibited IL-4 expression. RG products also alleviated ovalbumin-induced AR in mice. Of these, fRG most potently reduced nasal allergy symptoms and blood IgE levels. fRG treatment also reduced IL-4 and IL-5 levels in bronchoalveolar lavage fluid, nasal mucosa, and reduced mast cells, eosinophils, and Th2 cell populations. Furthermore, treatment with fRG reduced IL-4, IL-5, and IL-13 levels in the colon and restored ovalbumin-suppressed Bacteroidetes and Actinobacteria populations and ovalbumin-induced Firmicutes population in gut microbiota. Treatment with ginsenoside Rd significantly alleviated ovalbumin-induced AR in mice. CONCLUSION: fRG and ginsenoside Rd may alleviate AR by suppressing IgE, IL-4, IL-5, and IL-13 expression and restoring the composition of gut microbiota.

Lactobacillus plantarum NK3 and Bifidobacterium longum NK49 Alleviate Bacterial Vaginosis and Osteoporosis in Mice by Suppressing NF-κB-Linked TNF-α Expression.

Excessive expression of TNF-α worsens bacterial vaginosis (BV) and osteoporosis. Therefore, to understand whether probiotics could alleviate vaginosis and osteoporosis, we isolated anti-inflammatory Lactobacillus plantarum NK3 and Bifidobacterium longum NK49 from kimchi and human fecal lactic acid bacteria collection and examined their effects on Gardnerella vaginalis (GV)-induced vaginosis and ovariectomy-induced osteoporosis in female mice. Oral gavage of NK3 and/or NK49 significantly alleviated GV-induced vaginosis; these inhibited NF-κB activation and TNF-α expression in the vagina and uterus, and decreased the GV population in the vagina. Furthermore, treatment with NK3 and/or NK49 alleviated ovariectomy-induced osteoporosis and obesity; these increased blood calcium, phosphorus, and osteocalcin levels and suppressed body weight. GV-induced vaginosis and ovariectomy increased colonic myeloperoxidase activity, TNF-α expression, and fecal Proteobacteria population. NK3 and/or NK49 treatments reduced TNF-α expression and NF-κB activation in the colon. NK3 and NK49 treatment also restored GV- or ovariectomy-disrupted gut microbiota composition. In conclusion, NK3 and NK49 may simultaneously alleviate BV and osteoporosis by suppressing NF-κB-linked TNF-α expression through the regulation of gut microbiota population.

Lactobacillus plantarum LC27 and Bifidobacterium longum LC67 simultaneously alleviate high-fat diet-induced colitis, endotoxemia, liver steatosis, and obesity in mice.

Long-term feeding of a high-fat diet (HFD) induces endotoxemia and gastrointestinal inflammation by disturbing gut microbiota composition and membrane permeability, resulting in the acceleration of obesity. Some probiotics exhibit anti-inflammatory effects in vitro and in vivo. Therefore, we hypothesized that anti-inflammatory probiotics could lead to the simultaneous attenuation of endotoxemia, liver steatosis, obesity, and colitis in mice with HFD-induced obesity. Herein, we examined whether Lactobacillus plantarum LC27 and/or Bifidobacterium longum LC, which significantly suppressed NF-κB activation in lipopolysaccharide- or fecal lysate-stimulated Caco-2 cells, could simultaneously alleviate liver steatosis and colitis in mice with HFD-induced obesity. Oral administration of LC27, LC67, or their (3:1) mixture (LM) reduced HFD-induced aspartate transaminase, alanine transaminase, triglyceride, total cholesterol, and lipopolysaccharide levels in the blood and liver. Their treatments also suppressed HFD-induced NF-κB activation and increased AMP-activated protein kinase (AMPK) activation and claudin-1 and occludin expression in the liver and colon. Moreover, LC27, LC67, or LM treatment reduced HFD-induced Firmicutes and Proteobacteria populations in gut microbiota and fecal lipopolysaccharide production. The hypothesis was supported by the findings that anti-inflammatory LC27 and/or LC67 simultaneously alleviated liver steatosis, obesity, and colitis by regulating NF-κB and AMPK activation through the inhibition of gut microbiota lipopolysaccharide production.

Blackcurrant (Ribes nigrum) Prevents Obesity-Induced Nonalcoholic Steatohepatitis in Mice.

OBJECTIVE: With increasing prevalence of nonalcoholic steatohepatitis (NASH), effective strategies to prevent NASH are needed. This study investigated whether the consumption of blackcurrant (Ribes nigrum) can prevent the development of obesity-induced NASH in vivo. METHODS: Male C57BL/6J mice were fed a low-fat control diet, a low-fat diet with 6% whole blackcurrant powder, an obesogenic high-fat/high-sucrose control diet (HF), or a high-fat/high-sucrose diet containing 6% whole blackcurrant powder (HF-B) for 24 weeks. RESULTS: HF significantly increased, whereas HF-B markedly decreased, liver weights and triglyceride. Furthermore, blackcurrant attenuated obesity-induced infiltration of macrophages in the liver, in particular, the M1 type, and also suppressed the hepatic expression of fibrogenic genes and fibrosis. Flow cytometric analysis showed that HF significantly increased the percentages of monocytes of total splenocytes, which was markedly attenuated by blackcurrant. HF-B decreased lipopolysaccharide-stimulated mRNA expression of interleukin 1ß and tumor necrosis factor α in splenocytes, compared with those from HF controls. Moreover, the levels of circulating and hepatic miR-122-5p and miR-192-5p, known markers for nonalcoholic fatty liver disease, were significantly increased by HF but decreased by HF-B. CONCLUSIONS: The study's findings indicate that blackcurrant consumption prevents obesity-induced steatosis, inflammation, and fibrosis in the liver.

Lactobacillus plantarum C29 Alleviates TNBS-Induced Memory Impairment in Mice.

In a preliminary study, Lactobacillus plantarum C29 was found to suppress 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in mice. Therefore, to understand whether an anti-colitic probiotic C29 could attenuate memory impairment, we examined the effects of C29 on TNBS-induced memory impairment in mice. Orally administered Lactobacillus plantarum C29 attenuated TNBS-induced memory impairment in mice in the Y-maze, noble object, and passive avoidance task tests. C29 treatment increased TNBS-suppressed hippocampal brain-derived neurotrophic factor expression and inhibited TNBS-induced hippocampal NF-kappaB activation and blood LPS levels. Moreover, C29 restored the TNBS-disturbed gut microbiota composition. These findings suggest that C29 can alleviate memory impairment presumably by restoring the gut microbiota composition.

Lactobacillus plantarum LC27 and Bifidobacterium longum LC67 mitigate alcoholic steatosis in mice by inhibiting LPS-mediated NF-κB activation through restoration of the disturbed gut microbiota.

Long-term exposure to ethanol simultaneously causes gastrointestinal inflammation, liver injury, and steatosis. In the present study, we investigated the effects of Bifidobacterium longum LC67, Lactobacillus plantarum LC27, and their mixture (LM) against ethanol-induced steatosis in mice. Exposure to ethanol caused liver damage: it increased ALT, AST, TG, TC, and lipopolysaccharide levels in the blood and induced NF-κB activation in the liver. Oral administration of LC27, LC67, or LM in mice reduced ethanol-induced ALT, AST, TG, and TC levels in the blood and liver. These also suppressed ethanol-induced NF-κB activation and α-smooth muscle actin expression in the liver and increased ethanol-suppressed AMPK activation. Treatment with LC27, LC67, or LM increased ethanol-suppressed alcohol dehydrogenase and acetaldehyde dehydrogenase activities in the liver, as well as tight junction protein expression in the liver and colon. Moreover, treatment with LC27, LC67, or LM restored the ethanol-disturbed gut microbiota composition, such as the increased population of Proteobacteria, and inhibited fecal and blood lipopolysaccharide levels. These inhibited NF-κB activation and increased tight junction protein expression in ethanol- or lipopolysaccharide-stimulated Caco-2 cells. These findings suggest that LC27, LC67, and LM can alleviate alcoholic steatosis by inhibiting LPS-mediated NF-κB activation through restoration of the disturbed gut microbiota.

Simultaneous Amelioratation of Colitis and Liver Injury in Mice by Bifidobacterium longum LC67 and Lactobacillus plantarum LC27.

Disturbances in the gut microbiota composition are associated with chronic inflammatory diseases of the intestine and the liver. In a preliminary study, Lactobacillus plantarum LC27 and Bifidobacterium longum LC67 could inhibit Escherichia coli growth and lipopolysaccharide-induced NF-κB activation linked to gut inflammation. Here, we investigated their effects on 2,4,6-trinitrobenzesulfonic acid (TNBS)-induced colitis and liver damage in mice. First, oral administration of LC27 or LC67 (1 × 109 CFU/mouse) inhibited TNBS-induced colon shortening [F(5,30) = 100.66, P < 0.05] and myeloperoxidase activity [F(5,30) = 56.48, P < 0.05]. These probiotics restored TNBS-induced disturbance of gut microbiota, leading to the suppression of Proteobacteria to Bacteroidetes ratio and fecal and blood lipopolysaccharide levels. Second, LC27 and LC67 inhibited TNBS-induced NF-κB activation, reversed TNBS-suppressed tight junction protein expression, and restored Th17/Treg balance. Also, treatment with LC27 or LC67 significantly decreased TNBS-induced alanine transaminase [ALT, F(5,30) = 3.50, P < 0.05] and aspartate transaminase [AST, F(5,30) = 12.81, P < 0.05] levels in the blood, as well as t-butylhydroperoxide-induced ALT and AST levels. Finally, the mixture of LC27 and LC67 (0.5 × 109 CFU/mouse, respectively) synergistically attenuated TNBS- or t-butylhydroperoxide-induced colitis and liver damage. The capability of LC27 and LC67 to reverse TNBS-mediated microbiota shift and damage signals suggests that these probiotics may synergistically attenuate colitis and liver injury by alleviating gut microbiota imbalance.

Evidence for interplay among antibacterial-induced gut microbiota disturbance, neuro-inflammation, and anxiety in mice.

The aim of the present study was to determine whether there is the mechanistic connection between antibacterial-dependent gut microbiota disturbance and anxiety. First, exposure of mice to ampicillin caused anxiety and colitis and increased the population of Proteobacteria, particularly Klebsiella oxytoca, in gut microbiota and fecal and blood lipopolysaccharide levels, while decreasing lactobacilli population including Lactobacillus reuteri. Next, treatments with fecal microbiota of ampicillin-treated mouse (FAP), K. oxytoca, or lipopolysaccharide isolated from K. oxytoca (KL) induced anxiety and colitis in mice and increased blood corticosterone, IL-6, and lipopolysaccharide levels. Moreover, these treatments also increased the recruitment of microglia (Iba1+), monocytes (CD11b+/CD45+), and dendritic cells (CD11b+/CD11c+) to the hippocampus, as well as the population of apoptotic neuron cells (caspase-3+/NeuN+) in the brain. Furthermore, ampicillin, K. oxytoca, and KL induced NF-κB activation and IL-1ß and TNF-α expression in the colon and brain as well as increased gut membrane permeability. Finally, oral administration of L. reuteri alleviated ampicillin-induced anxiety and colitis. These results suggest that ampicillin exposure can cause anxiety through neuro-inflammation which can be induced by monocyte/macrophage-activated gastrointestinal inflammation and elevated Proteobacteria population including K. oxytoca, while treatment with lactobacilli suppresses it.