Yen-Po Chen

Lactobacillus kefiranofaciens M1 isolated from milk kefir grains ameliorates experimental colitis in vitro and in vivo

Lactobacillus kefiranofaciens M1, isolated from and identified in Taiwanese milk kefir grain, has demonstrated immune-modulating activity. In the present study, we further investigated the effects of Lb. kefiranofaciens M1 on intestinal epithelial cells in vitro and on dextran sodium sulfate (DSS)-induced colitis in vivo. The possible mechanisms regarding the cytokine products and intestinal epithelial barrier restoration as well as the putative receptor for the protective effects of Lb. kefiranofaciens M1 were investigated. In vitro results indicated that Lb. kefiranofaciens M1 could strengthen the epithelial barrier function in vitro by increasing the transepithelial electrical resistance (TEER) and significantly upregulated the level of the chemokine CCL-20 at both the apical and basolateral sites. The in vivo effects of Lb. kefiranofaciens M1 on the regulation of intestinal physiology indicate that this strain could ameliorate DSS-induced colitis with a significant attenuation of the bleeding score and colon length shortening. Production of proinflammatory cytokines was decreased and that of the antiinflammatory cytokine IL-10 was increased in the DSS-treated mice given Lb. kefiranofaciens M1. The putative receptor for the protective effects of Lb. kefiranofaciens M1 was toll-like receptor 2 (TLR2), which was involved in probiotic-induced cytokine production in vitro and in attenuation of the bleeding score and colon length shortening in vivo. In this study, the kefir lactobacillus Lb. kefiranofaciens M1 clearly demonstrated an anticolitis effect. Based on these results, Lb. kefiranofaciens M1 has the potential to be applied in fermented dairy products as an alternative therapy for intestinal disorders.

The antiallergic effect of kefir Lactobacilli.

This study demonstrated that oral feeding of heat-inactivated Lactobacillus (L b.) kefiranofaciens M1 from kefir grains effectively inhibited immunoglobulin (Ig) E production in response to ovalbumin (OVA) in vivo. The pattern of cytokine production by splenocyte cells revealed that the levels of cytokines produced by T helper (Th) 1 cells increased, and those of cytokines produced by Th2 cells decreased in the heat-inactivated M1 feeding group. These findings indicated that Lactobacillus kefiranofaciens M1 in the kefir played an important role in antiallergic activities. By additional analysis using flow cytometry and microarray, the mechanism of suppression of IgE production by oral feeding of the heat-inactivated M1 probably occurs because of upregulation of the expression of Cd2, Stat4, and Ifnr leading to skewing the Th1/Th2 balance toward Th1 dominance, elevation of the CD4(+)CD25(+) regulatory T (Treg) percentage, and reduction of activated CD19(+) B cells. Downregulation of complement system and components was also involved in suppression of IgE production. Practical Application: Kefir has long been considered good for health. Its health benefits include immunoregulatory effects. However, there is a lack of knowledge concerning the immunoregulatory effects induced by kefir lactic acid bacteria (LAB). Our data clearly demonstrated the antiallergic activity of kefir LAB, Lactobacillus (L b.) kefiranofaciens M1. By additional analysis using flow cytometry and microarray, the possible mechanism of suppression of IgE production by oral feeding of the heat-inactivated M1 was also elucidated. Our findings indicated that Lactobacillus kefiranofaciens M1 may have a great potential for utilization in functional food products.

Effects of Lactobacillus kefiranofaciens M1 isolated from kefir grains on enterohemorrhagic Escherichia coli infection using mouse and intestinal cell models

A potential probiotic strain, Lactobacillus kefiranofaciens M1, was previously isolated from kefir grains, which are used to manufacture the traditional fermented drink kefir. The aim of this study was to investigate the effects of Lb. kefiranofaciens M1 on enterohemorrhagic Escherichia coli (EHEC) infection, using mice and intestinal cell models. BALB/c mice were daily administrated with either phosphate buffered saline or Lb. kefiranofaciens M1 at 2×10(8) cfu/mouse per day intragastrically for 7 d. Intragastric challenges with EHEC (2×10(9) cfu/mouse) were conducted on d 0, 4, and 7 after treatment. Administration of Lb. kefiranofaciens M1 was able to prevent EHEC infection-induced symptoms, intestinal damage, renal damage, bacterial translocation, and Shiga toxin penetration. Furthermore, the mucosal EHEC-specific IgA responses were increased after Lb. kefiranofaciens M1 administration in the EHEC-infected mouse system. Additionally, in vitro, Lb. kefiranofaciens M1 was shown to have a protective effect on Caco-2 intestinal epithelial cells and Caco-2 intestinal epithelial cell monolayers; the bacteria limited EHEC-induced cell death and reduced the loss of epithelial integrity. These findings support the potential of Lb. kefiranofaciens M1 treatment as an approach to preventing EHEC infection and its effects.

Effects of Lactobacillus kefiranofaciens M1 isolated from kefir grains on germ-free mice.

Lactobacillus kefiranofaciens M1 is a novel probiotic strain that was isolated from kefir grains. Previously, we have demonstrated the immunoregulatory, anti-allergic, anti-asthmatic and anti-colitis abilities of L. kefiranofaciens M1 in a number of in-vitro and in-vivo experiments. However, whether the effects of L. kefiranofaciens M1 are elicited directly on the host or act by regulating the hosts microbiota remains unknown. A number of studies have used germ-free or gnotobiotic animals to investigate the relationship between probiotics and colitis; therefore the aim of this study was to investigate the effects of L. kefiranofaciens M1 on germ-free mice. Such an approach should help in determining the direct effects of L. kefiranofaciens M1 on the host itself. Four-week-old female germ-free mice were inoculated intragastrically with 2×108 CFU/mouse L. kefiranofaciens M1 once or at 2-day intervals for 14 days. Bacterial colonization, the Th1/Th2 cytokine profile of the mices splenocytes and the anti-colitis effect of L. kefiranofaciens M1 were investigated. The strongest response in terms of splenic Th1 cytokine IFN-γ and IL-12 production upon TLR activation was detected in the continuous treatment group when comparing to the single inoculation group and the germ-free control. In addition, continuous inoculation with L. kefiranofaciens M1 was found to ameliorate the symptoms of DSS-induced colitis in germ-free mice. However, L. kefiranofaciens M1 failed to colonize the host. Thus it would seem that L. kefiranofaciens M1 is likely to act directly on the host and not be involved in microbiota regulation.

Effect of Heat-Inactivated Kefir-Isolated Lactobacillus kefiranofaciens M1 on Preventing an Allergic Airway Response in Mice

In this study, we assessed the anti-asthmatic effects of heat-inactivated Lactobacillus kefiranofaciens M1 (HI-M1) and its fermented milk using different feeding procedures and at various dosage levels. The possible mechanisms whereby HI-M1 has anti-allergic asthmatic effects were also evaluated. Ovalbumin (OVA)-allergic asthma mice that have been orally administrated the HI-M1 samples showed strong inhibition of production of T helper cell (Th) 2 cytokines, pro-inflammatory cytokines, and Th17 cytokines in splenocytes and bronchoalveolar fluid compared to control mice. An increase in regulatory T cell population in splenocytes in the allergic asthma mice after oral administration of H1-M1 was also observed. In addition, all of the features of the asthmatic phenotype, including specific IgE production, airway inflammation, and development of airway hyperresponsiveness, were depressed in a dose-dependent manner by treatment. These findings support the possibility that oral feeding of H1-M1 may be an effective way of alleviating asthmatic symptoms in humans.

The Antiinfective Effects of Velvet Antler of Formosan Sambar Deer (Cervus unicolor swinhoei) on Staphylococcus aureus-Infected Mice

We assayed the effects of velvet antler (VA) of Formosan sambar deer (Cervus unicolor swinhoei) and its extracts on the anti-infective activity against pathogenic Staphylococcus aureus in vitro and in vivo in this study. In vitro data indicated that the VA extracts stimulated the proliferation of resting splenocytes and macrophages in a dose-dependent manner up to the highest concentration used (150 μg mL−1). The production of proinflammatory cytokines (TNF-α, IL-6, IL-12) by lipoteichoic acid was significantly suppressed after being cocultured with the VA extracts in a dose-dependent manner. Animal test in S. aureus-infected mice demonstrated that the numbers of bacteria determined in the kidneys and peritoneal lavage fluid of S. aureus-infected mice were significantly higher than those found in the same organs of mice pretreated with the VA samples. Moreover, the highly enhanced phagocytic activity of macrophages was further verified after in vitro treatment with the VA samples. The protective mechanisms of the VA samples might include an immune enhancer and an inflammatory cytokine suppressor.

Effects of a novel encapsulating technique on the temperature tolerance and anti-colitis activity of the probiotic bacterium Lactobacillus kefiranofaciens M1.

Lactobacillus kefiranofaciens M1 (M1) has been shown to possess many different beneficial health effects including anti-colitis activity. The purpose of this study was to develop a novel and easily scaled-up encapsulating technique that would improve the temperature tolerance of the bacterium and reduce the sensitivity of the organism to gastrointestinal fluid. A mixture of sodium alginate, gellan gum and skim milk powder was used as a coating material to entrap M1. The M1 gel was then directly freeze dried in order to dehydrate the covering and form microcapsules. The viable cell numbers of M1 present only dropped ten folds after the freeze-drying encapsulation process. The viable cell counts remained constant at 5 × 10(7) CFU/g after heating from 25 °C to 75 °C and holding at 75 °C for 1 min. The viable cell counts were reduced to 10(6) CFU/g and 10(5) CFU/g after 8-week storage at 4 °C and subsequent heat treatment with simulated gastrointestinal fluid test (SGFT) and bile salts, respectively. The effect of encapsulated M1 on the organisms anti-colitis activity was evaluated using the dextran sodium sulfate (DSS) induced colitis mouse model. An in vivo study indicated that administration of heat treated encapsulated M1 was able to ameliorate DSS-induced colitis producing a significant reduction in the bleeding score and an attenuation of inflammatory score. These findings clearly demonstrate that encapsulation of M1 using this novel technique is able to provide good protection from temperature changes and SGFT treatment and also does not affect the organisms anti-colitis activity.

Effect of the Velvet Antler of Formosan Sambar Deer (Cervus unicolor swinhoei) on the Prevention of an Allergic Airway Response in Mice

Two mouse models were used to assay the antiallergic effects of the velvet antler (VA) of Formosan sambar deer (Cervus unicolor swinhoei) in this study. The results using the ovalbumin- (OVA-) sensitized mouse model showed that the levels of total IgE and OVA-specific IgE were reduced after VA powder was administrated for 4 weeks. In addition, the ex vivo results indicated that the secretion of T helper cell 1 (Th1), regulatory T (Treg), and Th17 cytokines by splenocytes was significantly increased (P < 0.05) when VA powder was administered to the mice. Furthermore, OVA-allergic asthma mice that have been orally administrated with VA powder showed a strong inhibition of Th2 cytokine and proinflammatory cytokine production in bronchoalveolar fluid compared to control mice. An increase in the regulatory T-cell population of splenocytes in the allergic asthma mice after oral administration of VA was also observed. All the features of the asthmatic phenotype, including airway inflammation and the development of airway hyperresponsiveness, were reduced by treatment with VA. These findings support the hypothesis that oral feeding of VA may be an effective way of alleviating asthmatic symptoms in humans.

Effects of Lactobacillus paracasei 01 fermented milk beverage on protection of intestinal epithelial cell in vitro

BACKGROUND Intestinal protection is an important function of probiotics. However, there is no evidence that the potential probiotic Lactobacillus paracasei 01 is able to improve intestinal function. In the present study, the protective effect and underlying mechanisms of L. paracasei 01 on intestinal epithelial cell in vitro were investigated. RESULTS A fermented milk beverage containing L. paracasei 01 at 3 × 10(8) CFU mL(-1) was made from skim milk powder, glucose, sucrose and isomaltooligosaccharide. Results indicated that L. paracasei 01 fermented milk beverage could reduce macromolecule permeability caused by dextran sodium sulfate-induced damage. Besides, 50 mL L(-1) fermented milk beverage with live L. paracasei 01 in the cell medium could increase intestinal epithelial cell Caco-2 growth, decrease lipopolysaccharide/tumor necrosis factor-α (TNF-α)/interferon-γ (IFN-γ)-induced Caco-2 cell death and chemokine CCL-20 production. The protecting mechanisms involve promoting intestinal epithelial cell growth and intestinal epithelial integrity to strengthen the intestinal barrier against chemical and inflammatory stimuli-induced damage. Inhibition of inflammatory cytokines and chemokine such as IFN-γ, TNF-α and CCL-20 also contributes to the beneficial effects of this product on epithelial function. CONCLUSION Lactobacillus paracasei 01 fermented milk beverage may be a new functional food with intestinal protecting effects in vitro.