Introduction
Inflammatory bowel disease (IBD) which includes Crohn’s disease and ulcerative colitis (UC), are a group of chronic diseases that result from a confluence of genetic and environmental factors (Podolsky, 2005). Although current reviews have summarized some of the evidence regarding the mechanisms behind IBD, these diseases are not yet fully understood.
The WHO defines probiotic bacteria as live organisms which provide a benefit to the host when provided in adequate quantities (FAO/WHO, 2002). The human gastrointestinal immune system could potentially be regulated by intestinal microbiota, and probiotics are currently being evaluated as an alternative means of manipulating this microbiota in patients with chronic inflammation (Madsen et al., 2001). Probiotics have demonstrated their efficacy for a number of inflammatory conditions including arthritis (Bedaiwi and Inman, 2014). Importantly, probiotics have also been associated with the treatment of ulcerative colitis (UC) and Crohn’s disease (CD) (Fujimori et al., 2007).
In addition, it was well-established that several herbal compounds have been used to prevent and treat immune-associated disease in Asian countries. Among them, Astragali Radix (AR; Astragalus) appears to exert immunomodulatory effects by regulating the expression of cytokines such as IL-1α IL-1β, IL-6, inducible nitric oxide synthase (iNOS), and the production of nitric oxide (NO) (Lee et al., 2005). Also, Gleditsia sinensis Lam. has been used in traditional medicine for treatment of swelling, carbuncles, and other skin problems (Chow et al., 2003). The biological activity of these chemical compounds has been shown to be anti-mutagenic, anti-HIV, and anti-tumor (Li et al., 2007; Yi et al., 2015). The mechanism behind the anti-inflammatory effects of G. sinensis, however, remains unclear.
Inflammation is a protective response triggered by infection or tissue injury that is controlled by pro-inflammatory mediators (Bamias et al., 2012). Intestinal epithelial cells (IECs) in particular secrete mediators that are involved in immune responses to potentially pathogenic organisms, including antibacterial peptides such as defensins (Takahashi et al., 2001). Although a number of signaling molecules including NF-κB (commonly consists of the p50 and p65 subunits) and AKT are involved in inflammation, the specific mode of action is currently still unclear. Equally importantly, several in vivo animal models of IBD have been designed, and amongst them the dextran sulfate sodium (DSS)-induced colitis model appears to represent the most accurate model of IBD since it mimics human IBD-like symptoms (Okayasu et al., 1990).
The aim of this study was to evaluate the anti-inflammatory effects of probiotic strains and herbal extracts by measuring NF-κB translocation and AKT phosphorylation levels in LPS stimulated human intestinal epithelial HT-29 cells. In addition, we evaluated the anti-inflammatory effects of probiotics and natural compounds on DSS-induced chronic colitis in mice.
Materials and Methods
Gleditsia sinensis Lam
Fresh Gleditsia sinensis Lam. (GS) was purchased from a local herb mart, the Kyung-Dong market (Korea). The methanol GS extracts were kindly provided by the Natural Product and Metabolomics Laboratory at Korea University. These extracts were dissolved in dimethyl sulfoxide (DMSO) for cell treatment.
Bacteria and cell culture
Lactobacillus brevis KY21 (isolated from Korean infant feces), L. salivarius E4191 (isolated from Egyptian infant feces), and Leuconostoc mesenteroides subsp. mesenterides KDK411 (isolated from Kimchi) used in this study were generated in the Sae Hun Kim group (Food Microbiology Laboratory at Korea University, Korea). The strains were cultured in de Man, Rogosa, and Sharpe (MRS) broth (Difco, USA) at 37℃ for 18 h. The stock cultures were maintained at −80℃, using 50% glycerol as a cryoprotectant. The strains were sub-cultured three times prior to use.
The human epithelial cell line, HT-29, was obtained from the Korea Cell Line Bank (KCLB, Korea). The HT-29 cells were maintained at 37℃ with 5% CO2 in RPMI 1640 medium (HyClone, USA) supplemented with 10% heat-inactivated fetal bovine serum (FBS) (HyClone) and 1% penicillin/streptomycin (P-S; HyClone). The HT-29 cells were seeded on a six-well plate (Palcon, USA) at a density of 1×106 cells/well for western blot and confocal analyses. The HT-29 cells were pre-treated with 100 μg/mL of GS extract or 109 CFU/mL probiotic bacteria for 2 h and cultured with 1 μg/mL of LPS (Escherichia coli strain, 0111:B4, Sigma, USA).
Western blot analysis
The HT-29 cells were harvested, washed with PBS, and treated with cell lysis solution (50 mM Tris, pH 7.2, 150 mM NaCl, 1% Triton X-100) added to 200 μg phenylmethylsulfonyl fluoride/mL, phosphatase inhibitor cocktail (Sigma), and protease inhibitor cocktail (EMD Chemicals. Inc., USA) at 4℃ for 1 h. Lysates were loaded on 10% polyacrylamide and transferred to an immobilon P membrane (Millipore Corporation, USA) and blocked with TBST including 5% skimmed milk (for total AKT) or TBST alone (for pAKT) at room temperature for 1 h. Afterwards, the membranes were incubated with purified total AKT antibody (Cell signaling, USA), pAKT antibody (#9611, Cell Signaling, USA), and then HRP-conjugated anti-mouse or anti-rabbit IgG (Amershamm, USA). Proteins were detected by the super signal Western blotting system and immunoreactive bands were visualized with an ECL system. The β-actin were used as internal control. The gel images were quantified using NIH Image J program (NIH http://rsb.info.nih.gov/ij/) and pAKT activity was determined by the ratio of pAKT/total AKT.
Confocal microscopy
HT-29 cells were seeded onto round coverslips and pretreated with GS extract (100 mg/mL) or probiotic bacteria (109 CFU/mL) for 2 h followed by a PBS wash to remove the unbound bacteria. Cultured HT-29 cells were stimulated by 1 μg/mL of LPS. After 24 h incubation, HT-29 cells were fixed in 4% (w/v) formaldehyde in phosphate-buffered saline (PBS) for 30 min. The cell were permeabilized with 0.2% (w/v) Triton X-100 in PBS for 20 min. And then cells were washed three times with PBS and shaken while incubated with blocking solution (3% bovine serum albumin in PBS) for 1 h at room temperature. The cells were next incubated with primary antibodies to NF-κB p65 (Santa Cruz Biotechnology, 1:200) for 24 h, followed by three PBS washes to remove unbound primary antibody. This was followed by incubation with Alexa fluor 592 conjugated anti-rabbit IgG for 1 h at room temperature, and subsequent staining with 100 ng/mL DAPI in PBS for 30 min. Finally, confocal images were obtained using a LSM5 EXCITER (carl-Zeiss, Germany).
Assessment of inflammation in DSS-induced colitis
Eight-week-old female BALB/c mice were purchased from SamTaKo (Daejeon, Korea). They were acclimatized for one week before the start of the experiment, and were housed individually in a room maintained at 22℃ under a 12 h day/night cycle throughout the study. The mice were divided into six groups as follows and administered using oral gavage: (i) mice fed 4% DSS (molecular weight 5000; Wako Pure Chemical Industries, Ltd, Japan) mixed with water and DSS water ad libitum; (ii) mice fed 4% DSS plus 1 g GS extract/kg; (iii) mice fed DSS plus 109 CFU of L. brevis/kg in PBS; (iv) mice fed 50 mg sulfasalazine/kg (Sigma; positive control); (v) mice fed 4% DSS plus a combination of GS extract and L. brevis KY21; and (vi) mice fed PBS only (negative control).
A daily clinical assessment of DSS-induced colitis was performed, including measurement of food intake, body weight, rectal bleeding, an evaluation of stool condition, and the presence of blood in the stools. The mice were sacrificed on day 14 following the initiation of DSS treatment, and the length and weight of the colon were measured.
Histological evaluation
A histological examination was performed on samples of the distal colon from each animal. The samples were fixed in 10% buffered formalin, dehydrated in ethanol, and then embedded in paraffin. Four micron-thick sections were then prepared and stained with hematoxylin and eosin (H/E). All histological evaluations were performed in a blinded fashion using a validated scoring system (Dieleman et al., 1998). In briefly, the sections were graded with a range from 0 to 3 for total inflammation and 0 to 4 for extent of crypt damage.
Reverse transcription polymerase chain reaction (RT-PCR)
Total cellular RNA was extracted from the mesenteric lymph nodes (MLN) and spleens of the mice using TrizoleTM reagent (Invitrogen, USA) according to the manufacturer’s instructions, and was further purified using acidic phenol/chloroform extraction. cDNA was then generated using SuperScript III reverse transcriptase (Invitrogen). After cDNA synthesis, PCR was performed as follows: denaturation for 30 s at 95℃, annealing for 30 s at 60℃, and extension for 30 s at 72℃ for 35 cycles. The primer sequences used for RT-PCR are listed in Table 1. RT-PCR products were electrophoresed on a 2% agarose gel and visualized by ethidium bromide (EtBr) staining. All results were finalized after correction with GAPDH expression.
Table 1.Oligonucleotides used in this study. f indicates forward primers and r indicates reverse primers
Statistical analysis
Differences between groups in each experiment were determined using Student’s t-tests or ANOVA, followed by Duncan’s test in SAS software package (ver. 9.1; SAS Inc., USA). Each result is representative of at least three independent biological replicates. A p-value of <0.05 in all replicate experiments was considered to be statistically significant.
Results and Discussion
Anti-inflammatory effects of GS extract and L. brevis KY21 on IECs
Inhibition of AKT phosphorylation in HT-29 cells
It has been well-established that pro-inflammatory cytokines including IL-8, a member of the CXC family of chemokines, are potent chemo-attractant that activates neutrophils (Baggiolini et al., 1989). Especially, IL-8 is produced in response to stimulation by TNF-α (Abreu-Martin et al., 1995). Inhibition of these two pathways resulted in a blockage of TNF-α-inducible IL-8 production and also induced apoptosis (Osawa et al., 2002). Importantly, TNF-α-induced IL-8 production was critically correlated with activation of the PI3K/AKT pathways that leading to cell survivals and immune response. Thus, we determined on the regulation of total AKT activity in the presence of GS extract or probiotic strains GS, KY21, KDK414, and E4191 using western blotting. The β-actin was employed as control. Unexpectedly, Western blot results showed that there was no significant difference on the total AKT activity among LPS treatment or GS extract/probiotic strains (ranged from 0.9 to 1.1 with the ration of pAKT/total AKT in all treatment; Fig. 1A).
Fig. 1.Effects of GS extract and LAB strains on LPS-induced phosphorylation of AKT (A) and translocation of nuclear factor (NF)-κB p65 to the nucleus (B). HT-29 cells were pre-treated with either GS extract (100 μg/mL) or probiotic strains E4191, KY21, or KDK411 (109 CFU/mL) for 2 h, and then stimulated with LPS (1 μg/mL, 24 h). The level of AKT phosphorylation (pAKT) was decreased by GS extract in HT-29 cells assayed by Western blot. For p65 assay, HT-29 cells were pre-treated with either GS extract (100 μg/mL) or probiotic strains E4191, KY21, or KDK411 (109 CFU/mL) for 2 h, and then stimulated with 1 μg/mL LPS for 24 h. Immunofluorescence 4',6-Diamidino-2-phenylindole (DAPI) was used to stain the nuclei. Bar scale is 5 mm. The result is representative of at least three independent biological replicates.
Next, to determine the phosphorylation of AKT (pAKT), the cells were immunoblotted with phosphorylated AKT antibodies. As reported in Fig. 1A, the phosphorylation level of AKT was decreased by 4-folds when they exposed to 100 mg/mL of GS extract. However, the probiotic strains KDK414 and E4191 did not have any effect on AKT phosphorylation with the exception of L. brevis KY 21 (3-folds). These results show that GS and L. brevis KY 21 directly affect the regulation of pAKT, and these features can influence on the cascade response in inflammatory associated cytokine networks.
Inhibition of NF-κB translocation in HT-29 cells
In investigating the effects of anti-inflammatory agents on HT-29 cells stimulated by LPS, it is important to note that NF-κB exists in the cytoplasm, primarily as the p50 and p65 subunits and the IκBα inhibitory protein
Anti-inflammatory effects of GS extract and L. brevis KY21 on a DSS-induced colitis model
Body weight and food intake
As shown in Fig 2A, after the initiation of DSS-induced colitis, body weight was significantly lower in the DSS group compared with the DSS plus either 1 g GS extract/kg or 109 CFU L. brevis KY21/kg or combination of GS extract and L. brevis KY21 (GS+ KY21), and the 50 mg/kg sulfasalazine (Sigma)-treated mice. In addition food intake was significantly lower in DSS-treated mice than in DSS plus GS extract, 109 CFU of L. brevis KY21/kg, and 50 mg sulfasalazine/kg (positive control)-treated mice on day 5 after the initiation of DSS treatment (Fig. 2B). Importantly, the combination of GS extract and L. brevis KY21 was most effective in alleviating weight loss and decreased food intake. This suggests that GS and L. brevis KY21 administration may help to prevent severe weight loss in cases of DSS-induced colitis.
Fig. 2.Effects of GS extract and L. brevis KY21 on body weight (A), food intake (B), colon length (C and D) and rectal bleeding (E) in DSS-induced mice. The mice were fed 4% DSS (mixed with water; ad libitum), 4% DSS plus GS extract (1 g/kg), 4% DSS plus 109 CFU/kg L. brevis KY21, 4% DSS plus combination of GS extract and L. brevis KY21, or 4% DSS plus 50 mg kg−1 sulfasalazine (SS; Sigma, USA) during day 14. The weight of each individual mouse was then followed daily. In addition, colon length was determined on day 14 after the start of DSS treatment. The data represent means±SEM. *p<0.05 versus the DSS group, **p<0.01 versus the DSS group, and †p<0.05 versus the untreated group (n=5 mice/group).
Observation of intestinal injury
Consistent with previous reports, oral administration of 4% DSS in drinking water to WT BALB/c mice induced moderate colitis, which was first manifest by diarrhea followed by bloody stools. A common feature of the DSS-induced colitis model is a significant decrease in colon length (Rumi et al., 2004). The length of the colon in DSS with GS, L. brevis KY21, GS+KY21, and sulfasalazine-treated mice was compared to that of DSS plus PBS (Fig. 2C and 2D). The percentage of mice with increased colon length in the DSS with GS group (24%), KY21 group (18%), GS+KY21 group (27%), and sulfasalazine group (34%) were significantly increased compared with DSS alone group. The weight of the colon was evaluated in proportion to colon length. The colonic weight/length ratio was higher in the DSS-treated mice compared with those treated with GS extract, KY21, GS+KY21, and sulfasalazine (data not shown). This ratio is a possible marker of tissue edema (Mizoguchi and Mizoguchi, 2008). In addition, mice supplemented with either GS extract or L. brevis KY21 showed significantly lower susceptibility to DSS-induced colitis than control mice, which was manifest by severe intestinal bleeding (Fig. 2E). Consistent with body weight and food intake, a synergistic impact of GS extract and L. brevis KY21 was observed with respect to protection from intestinal injury. Our findings demonstrate that treatment with GS extract and L. brevis KY21 resulted in significant protection against intestinal injury in cases of DSS-induced colitis.
Histological analysis and scores for intestinal mucosal wounds
A 10 mm colonic tissue sample was used for the histological assessment. Inflammation and crypt damage on H&E-stained sections were assessed using the standard method previously described (Dieleman et al., 1998). Damage to the colonic mucosa is shown by increased histological severity scores and decreased crypt area (Howarth et al., 1998). In the healthy control group, the crypt structure in the mucosal layer was regular, and the thickness of the submucosal and muscular layers was normal. In the UC control group, the crypt structure was irregular because of cryptitis and crypt disappearance, complete crypt loss, destruction of epithelial cells, and severe inflammatory cell infiltration, though the GS extract and GS+KY 21-treated groups did not exhibit these features (Fig. 3A). This result suggests that combined supplementation with GS extract and L. brevis KY21 notably prevented epithelial damage by the exposure of DSS.
Fig. 3.Histological staining (A), scores (B), and mRNA expression of cytokine-encoded genes in mesenteric lymph nodes and the spleens using RT-PCR (C) in cases of DSS-induced colitis supplemented with GS extract, L. brevis KY21, and sulfasalazine. The mice were fed 4% DSS (mixed with water; ad libitum), 4% DSS plus GS extract (1 g/kg), 4% DSS plus 109 CFU/kg L. brevis KY21, 4% DSS plus combination of GS extract and L. brevis KY21, or 4% DSS plus 50 mg kg−1 sulfasalazine (SS; Sigma, USA) during day 14. The colons were excised on day 14 after DSS treatment was initiated and stained with hematoxylin and eosin (H/E). Magnification × 200. The total histological scores were derived from the severity of total inflammation and extent of crypt damage. The data represent means±SEM. *p<0.05 versus the DSS group. L: DNA ladder marker (Invitrogen).
mRNA expression of cytokine encoded genes in mesenteric lymph nodes and the spleen
The mesenteric lymph nodes and spleen were used to evaluate the presence of TNF-α, IFN-γ, and IL-1β. These pro-inflammatory cytokines play an important role in the killing of tumor cells (Mantovani et al., 1992), and were increased by treatment with DSS (Fig. 3C). Cytokines induced by LAB are shown to play key roles in immune-regulation. Several studies have reported that some specific strains of lactobacilli can induce pro-inflammatory cytokines such as interleukin-1 (IL-1), IL-6, IL-12, tumor necrosis factor alpha (TNF-α), and gamma interferon (IFN-γ) as well as anti-inflammatory cytokines such as IL-10 and transforming growth factor β (Christensen et al., 2002). Sulfasalazine blocks the phosphorylation of the inhibitor kB (IkB) (Weber et al., 2000). Similarly, sulfasalazine inhibited all of these cytokines, whereas GS and L. brevis KY21 significantly inhibited the expression of TNF-α, IFN-γ, and IL-1β. Interestingly, the combination of GS extract and L. brevis KY21 was most effective in inhibiting the transcription of pro-inflammatory cytokines genes. This result demonstrated that ingestion of GS extract and L. brevis KY21 were able to inhibit the transcriptions of pro-inflammatory cytokine genes observed in DSS-induced colitis specifically, and prevent the initiation of the inflammatory response.
In conclusion, we investigated the synergic anti-inflammatory effects of GS extract and L. brevis KY21, both in vitro and in vivo. Our results showed that the combination of GS extract and L. brevis KY21 improve the recovery from intestinal damage and prevent reactivation of experimental colitis, supporting the potential use of this new protective or preventive strategy for IBD in the food industry.
References
- Abreu-Martin, M. T., Vidrich, A., Lynch, D. H., and Targan, S. R. (1995) Divergent induction of apoptosis and IL-8 secretion in HT-29 cells in response to TNF-alpha and ligation of Fas antigen. J. Immunol. 155, 4147-4154.
- Baggiolini, M., Walz, A., and Kunkel, S. L. (1989) Neutrophil-activating peptide-1/interleukin 8, a novel cytokine that activates neutrophils. J. Clin. Invest. 84, 1045-1049. https://doi.org/10.1172/JCI114265
- Bamias, G., Corridoni, D., Pizarro, T. T., and Cominelli, F. (2012) New insights into the dichotomous role of innate cytokines in gut homeostasis and inflammation. Cytokine 59, 451-459. https://doi.org/10.1016/j.cyto.2012.06.014
- Bedaiwi, M. K. and Inman, R. D. (2014) Microbiome and probiotics: Link to arthritis. Curr. Opin. Rheumatol. 26, 410-415. https://doi.org/10.1097/BOR.0000000000000075
- Chow, L. M., Chui, C. H., Tang, J. C., Teo, I. T., Lau, F. Y., Cheng, G. Y., Wong, R. S., Leung, T. W., Lai, K. B., Yau, M. Y., Gou, D., and Chan, A. S. (2003) Gleditsia sinensis fruit extract is a potential chemotherapeutic agent in chronic and acute myelogenous leukemia. Oncol. Rep. 10, 1601-1607.
- Christensen, H., Bisgaard, M., Angen, O., and Olsen, J. E. (2002) Final classification of Bisgaard taxon 9 as Actinobacillus arthritidis sp. nov. and recognition of a novel genomo-species for equine strains of Actinobacillus lignieresii. Int. J. Syst. Evol. Microbiol. 52, 1239-1246.
- Dieleman, L. A., Palmen, M. J., Akol, H., Bloemena, E., Peña, A. S., Meuwissen, S. G., and Van Rees, E. P. (1998) Chronic experimental colitis induced by dextran sulphate sodium (DSS) is characterized by Th1 and Th2 cytokines. Clin. Exp. Immunol. 114, 385-391. https://doi.org/10.1046/j.1365-2249.1998.00728.x
- FAO/WHO (2002) Joint FAO/WHO Working Group Report on Drafting Guidelines for the evaluation of Probiotics in Food.
- Fujimori, S., Tatsuguchi, A., and Gudis, K. (2007) High dose probiotic and prebiotic cotherapy for remission induction of active Crohn's disease. J. Gastroenterol. Hepatol. 22, 1199-1204. https://doi.org/10.1111/j.1440-1746.2006.04535.x
- Howarth, G. S., Xian, C. J., and Read, L. C. (1998) Insulin-like growth factor-I partially attenuates colonic damage in rats with experimental colitis induced by oral dextran sulphate sodium. Scand. J. Gastroenterol. 33, 180-190. https://doi.org/10.1080/00365529850166923
- Jamaluddin, M., Casola, A., Garofalo, R. P., Han, Y., Elliott, T., Ogra, P. L., and Brasier, A. R. (1998) The major component of IκBα proteolysis occurs independently of the proteasome pathway in respiratory syncytial virus-infected pulmonary epithelial cells. J. Virol. 72, 4849-4857.
- Lee, Y. S., Han, O. K., Park, C. W., Yang, C. H., Jeon, T. W., Yoo, W. K., Kim, S. H., and Kim, H. J. (2005) Pro-inflammatory cytokine gene expression and nitric oxide regulation of aqueous extracted Astragali radix in RAW 264.7 macrophage cells. J. Ethnopharmacol. 100, 289-294. https://doi.org/10.1016/j.jep.2005.03.009
- Li, W. H., Zhang, X. M., Tian, R. R., Zheng, Y. T., Zhao, W. M., and Qiu, M. H. (2007) A new anti-HIV lupane acid from Gleditsia sinensis Lam. J. Asian Nat. Prod. Res. 9, 551-555. https://doi.org/10.1080/10286020600883419
- Madsen, K. A. C., Soper, P., McKaigney, C. H. J., Yachimec, C., Doyle, J., Jewell, L., and De Simone, C. (2001) Probiotic bacteria enhance murine and human intestinal epithelial barrier function. Gastroenterol. 121, 580-591. https://doi.org/10.1053/gast.2001.27224
- Mantovani, A., Bussolino, F., and Dejana, E. (1992) Cytokine regulation of endothelial cell function. FASEB J. 6, 2591-2599. https://doi.org/10.1096/fasebj.6.8.1592209
- Mizoguchi, A. and Mizoguchi, E. (2008) Inflammatory bowel disease, past, present and future: Lessons from animal models. J. Gastroenterol. 43, 1-17. https://doi.org/10.1007/s00535-007-2111-3
- Okayasu, I., Hatakeyama, S., Yamada, M., Ohkusa, T., Inagaki, Y., and Nakaya, R. (1990) A novel method in the induction of reliable experimental acute and chronic ulcerative colitis in mice. Gastroenterol. 98, 694-702. https://doi.org/10.1016/0016-5085(90)90290-H
- Osawa, Y., Nagaki, M., Banno, Y., Brenner, D. A., Asano, T., Nozawa, Y., Moriwaki, H., and Nakashima, S. (2002) Tumor necrosis factor alpha-induced interleukin-8 production via NF-kappaB and phosphatidylinositol 3-kinase/Akt pathways inhibits cell apoptosis in human hepatocytes. Infect. Immun. 70, 6294-6301. https://doi.org/10.1128/IAI.70.11.6294-6301.2002
- Podolsky, D. K. (2005) Inflammatory bowel disease. N. Engl. J. Med. 358, 1965-1968.
- Rumi, G., Tsubouchi, R., Okayama, M., Kato, S., Mózsik, G., and Takeuchi, K. (2004) Protective effect of lactulose on dextran sulfate sodium-induced colonic inflammation in rats. Dig. Dis. Sci. 49, 1466-1472. https://doi.org/10.1023/B:DDAS.0000042248.48819.ad
- Takahashi, A., Wada, A., Ogushi, K., Maeda, K., Kawahara, T., Mawatari, K., Kurazono, H., Moss, J., Hirayama, T., and Nakaya, Y. (2001) Production of beta-defensin-2 by human colonic epithelial cells induced by Salmonella enteritidis flagella filament structural protein. FEBS Lett. 508, 484-488. https://doi.org/10.1016/S0014-5793(01)03088-5
- Weber, C. K., Liptay, S., Wirth, T., Adler, G., and Schmid, R. M. (2000) Suppression of NF-kB activity by sulfasalazine is mediated by direct inhibition of IkB kinases alpha and beta. Gastroenterol. 119, 1209-1218. https://doi.org/10.1053/gast.2000.19458
- Yi, J. M., Kim, J., Park, J. S., Lee, J., Lee, Y. J., Hong, J. T., Bang, O. S., and Kim, N. S. (2015) In vivo anti-tumor effects of the ethanol extract of Gleditsia sinensis thorns and its active constituent, cytochalasin H. Biol. Pharm. Bull. 38, 909-912. https://doi.org/10.1248/bpb.b14-00647
Cited by
- Anti-inflammatory effect of Man-Pen-Fang, a Chinese herbal compound, on chronic pelvic inflammation in rats vol.208, 2017, https://doi.org/10.1016/j.jep.2017.06.034
- Prophylactic use of probiotic chocolate modulates intestinal physiological functions in constipated rats pp.00225142, 2019, https://doi.org/10.1002/jsfa.9518
- Regulatory Effect of Lactobacillus brevis Bmb6 on Gut Barrier Functions in Experimental Colitis vol.9, pp.7, 2015, https://doi.org/10.3390/foods9070864
- Identification of Spices Promoting the Growth of Lactic Acid Bacteria and Modulation of Tight Junction Protein at mRNA Level by the Fermented Product of Red Pepper (Capsicum annuum L.) in HT-29 Cell vol.50, pp.1, 2015, https://doi.org/10.3746/jkfn.2021.50.1.16
- Bifidobacterium pseudocatenulatum Ameliorates DSS-Induced Colitis by Maintaining Intestinal Mechanical Barrier, Blocking Proinflammatory Cytokines, Inhibiting TLR4/NF-κB Signaling, and Altering vol.69, pp.5, 2021, https://doi.org/10.1021/acs.jafc.0c06329
- Therapeutic Effects of Gleditsia sinensis Thorn Extract Fermented by Lactobacillus casei 3260 in a Type II Collagen-Induced Rheumatoid Arthritis Mouse Model vol.41, pp.3, 2015, https://doi.org/10.5851/kosfa.2021.e13
- Linoleate Isomerase Complex Contributes to Metabolism and Remission of DSS-Induced Colitis in Mice of Lactobacillus plantarum ZS2058 vol.69, pp.29, 2021, https://doi.org/10.1021/acs.jafc.1c02944
- Bifidobacterium longum Ameliorates Dextran Sulfate Sodium-Induced Colitis by Producing Conjugated Linoleic Acid, Protecting Intestinal Mechanical Barrier, Restoring Unbalanced Gut Microbiota, and Regu vol.69, pp.48, 2015, https://doi.org/10.1021/acs.jafc.1c06176