Influence of administration timing of San-Huang-Xie-Xin-Tang treatment on attenuating Salmonella enterica serovar Typhimurium infection.

Salmonella infections are a serious global health concern, particularly in developing countries, and are further exacerbated by the emergence of antibiotic resistance. San-Huang-Xie-Xin-Tang (SHXXT), a traditional herbal medicine with potent anti-inflammatory properties, has recently gained attention as an alternative treatment. Our study emphasizes on the importance of precise timing in accordance with traditional Chinese medicine principles. A mouse infection model was established while different administration times of SHXXT were recorded for the body weight, clinical scores, bacterial counts in blood, and organs. Additionally, cytokine levels, fatty acids, and amino acids in the serum were also monitored. We found that administering SHXXT 1 day after Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium) infection (T1 group) leads to positive outcomes. This includes restoration of body weight, improved clinical scores, and reduced bacterial counts in blood and vital organs. Interferon-gamma levels remained consistently high across all treatment groups 6 days post-infection. However, the T1 group showed exclusive suppression of serum levels of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1ß). The timing of administration significantly influenced serum fatty acid concentrations, countering Salmonella-induced disruptions, aligning with TNF-α and IL-1ß levels. SHXXT had also restored amino acid profiles disrupted by the infection, with notable effects when administered at the correct timing. Our research highlights SHXXT's potential in treating S. Typhimurium infection, emphasizing the importance of precise timing in line with traditional Chinese medicine principles for effective treatment at different disease stages.

miR-221 confers lapatinib resistance by negatively regulating p27kip1 in HER2-positive breast cancer.

Development of acquired resistance to lapatinib, a dual epidermal growth factor receptor (EGFR)/human epidermal growth factor receptor 2 (HER2) tyrosine kinase inhibitor, severely limits the duration of clinical response in advanced HER2-driven breast cancer patients. Although the compensatory activation of the PI3K/Akt survival signal has been proposed to cause acquired lapatinib resistance, comprehensive molecular mechanisms remain required to develop more efficient strategies to circumvent this therapeutic difficulty. In this study, we found that suppression of HER2 by lapatinib still led to Akt inactivation and elevation of FOX3a protein levels, but failed to induce the expression of their downstream pro-apoptotic effector p27kip1 , a cyclin-dependent kinase inhibitor. Elevation of miR-221 was found to contribute to the development of acquired lapatinib resistance by targeting p27kip1 expression. Furthermore, upregulation of miR-221 was mediated by the lapatinib-induced Src family tyrosine kinase and subsequent NF-κB activation. The reversal of miR-221 upregulation and p27kip1 downregulation by a Src inhibitor, dasatinib, can overcome lapatinib resistance. Our study not only identified miRNA-221 as a pivotal factor conferring the acquired resistance of HER2-positive breast cancer cells to lapatinib through negatively regulating p27kip1 expression, but also suggested Src inhibition as a potential strategy to overcome lapatinib resistance.

Lactobacillus rhamnosus JB3 inhibits Helicobacter pylori infection through multiple molecular actions.

BACKGROUND: Eradication of Helicobacter pylori infection is the most direct and effective way for preventing gastric cancer. Lactic acid bacteria are considered as alternative therapeutic agents against H. pylori infection. METHODS: Effects of Lactobacillus rhamnosus JB3 (LR-JB3) on the virulence gene expression of H. pylori and infection-induced cellular responses of AGS cells were investigated by co-cultivating infected AGS cells with different multiplicity of infections (MOIs) of LR-JB3. RESULTS: LR-JB3, specifically at a MOI of 25, suppressed the association ability of H. pylori and its induced IL-8 levels, as well as the mRNA levels of vacA, sabA, and fucT of H. pylori, infection-induced Lewis (Le)x antigen and Toll-like receptor 4 (TLR4) expressions in AGS cells. However, the apoptosis mediated by infection was inhibited by LR-JB3 in a dose-dependent manner. In addition, autoinducer (AI)-2 was observed to have increased the association ability and fucT expression of H. pylori, and Lex antigen and TLR4 expression of AGS cells. Interestingly, an unknown bioactive cue was hypothesized to have been secreted from LR-JB3 at a MOI of 25 to act as an antagonist of AI-2. CONCLUSIONS: LR-JB3 possesses various means to interfere with H. pylori pathogenesis and infection-induced cellular responses of AGS cells to fight against infection.

Potential effects of allyl isothiocyanate on inhibiting cellular proliferation and inducing apoptotic pathway in human cisplatin-resistant oral cancer cells.

BACKGROUND/PURPOSE: Cisplatin-resistant oral cancer is clinically difficult to manage and the dose-dependent toxicities of cisplatin has been widely concerned. Allyl isothiocyanate (AITC), known as mustard oil, is a plant-derived compound abundant in cruciferous vegetables. It is reported to have anti-cancer potential as a natural dietary chemopreventive compound against a variety of cancers, but the effect of AITC on cisplatin-resistant cancer cells is still little-known. METHODS: Human CAL27-cisplatin-resistant oral cancer cells (CAR cells) were examined to investigate the antitumor properties of AITC. 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay, IncuCyte™ S3 cell proliferation assay, 4',6-diamidino-2-phenylindole (DAPI) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining as well as Western blot analysis were deployed. RESULTS: AITC decreased CAR cell viability, induced cell death of CAR cells and inhibited the confluences of cultured CAR cells. When CAR cells were treated with AITC, activation of caspase-3 and caspase-9 by AITC was observed and could be reversed by Z-VAD-fmk (pan-caspase inhibitor). Furthermore, the protein expressions of phosphorylated protein kinase B (p-AKT) and phosphorylated mammalian target of rapamycin (p-mTOR) were suppressed in AITC-treated CAR cells, whereas protein expressions of Bax, cytochrome c, Apaf-1, cleaved caspase-3, and cleaved caspase-9 were upregulated in AITC-treated CAR cells. CONCLUSION: AITC can inhibit Akt/mTOR proliferation signaling and promote mitochondria-dependent apoptotic pathway through AITC-enhanced activities of caspase-3 and caspase-9 in CAR cells.

Lupeol suppresses migration and invasion via p38/MAPK and PI3K/Akt signaling pathways in human osteosarcoma U-2 OS cells.

Lupeol, one of the common components from the fruits and natural foods, has been reported to exert antitumor activities in many human cancer cell lines; however, its effects on osteosarcoma cell metastasis were not elucidated. In the present study, lupeol at 10-25 µM induced cell morphological changes and decreased total viable cell number in U-2 OS cells. Lupeol (5-15 µM) suppressed cell mobility, migration, and invasion by wound healing and transwell chamber assays, respectively. Lupeol inhibited the activities of MMP-2 and -9 in U-2 OS cells by gelatin zymography assay. Lupeol significantly decreased PI3K, pAKT, ß-catenin, and increased GSK3ß. Furthermore, lupeol decreased the expressions of Ras, p-Raf-1, p-p38, and ß-catenin. Lupeol also decreased uPA, MMP-2, MMP-9, and N-cadherin but increased VE-cadherin in U-2 OS cells. Based on these observations, we suggest that lupeol can be used in anti-metastasis of human osteosarcoma cells in the future.

Cantharidin decreased viable cell number in human osteosarcoma U-2 OS cells through G2/M phase arrest and induction of cell apoptosis.

Cantharidin (CTD), a sesquiterpenoid bioactive substance, has been reported to exhibit anticancer activity against various types of cancer cells. The aim of the present study was to investigate the apoptosis effects and the underlying mechanisms of CTD on osteosarcoma U-2 OS cells. Results showed that CTD induced cell morphologic changes, reduced total viable cells, induced DNA damage, and G2/M phase arrest. CTD increased the production of reactive oxygen species and Ca2+, and elevated the activities of caspase-3 and -9, but decreased the level of mitochondrial membrane potential. Furthermore, CTD increased the ROS- and ER stress-associated protein expressions and increased the levels of pro-apoptosis-associated proteins, but decreased that of anti-apoptosis-associated proteins. Based on these observations, we suggested that CTD decreased cell number through G2/M phase arrest and the induction of cell apoptosis in U-2 OS cells and CTD could be a potential candidate for osteosarcoma treatments.

Pteris multifida, Cortex phellodendri, and probiotics attenuated inflammatory status and immunity in mice with a Salmonella enterica serovar Typhimurium infection.

Pteris multifida (PM) and Cortex phellodendri (CP) are medicinal foods used for gastrointestinal protection. Lactic-acid bacteria are probiotics. Salmonella Typhimurium strain ST21-infected mice were used to examine the alleviative effects of two lactic-acid bacteria (LAB) as well as aqueous extracts of PM and CP for a 4-day treatment. CP and LAB decreased fecal ST counts. CP and PM reduced the ST21 count in the blood, intestine, and liver. LAB lowered the ST21 count in the intestine and spleen. CP and LAB decreased the IFN-gamma level; PM lowered the TNF-alpha level; and both LAB and PM reduced the IL-1beta level in serum. PM and CP lowered the IgG level in serum. The data in a macrophage infection model indicate that TNF-alpha was partial involved in this alleviative effects, other mechanisms might be involved. In sum, these novel findings suggest that PM, CP, and LAB probiotics are potential anti-Salmonellae agents.

Epigallocatechin gallate sensitizes cisplatin-resistant oral cancer CAR cell apoptosis and autophagy through stimulating AKT/STAT3 pathway and suppressing multidrug resistance 1 signaling.

Epigallocatechin gallate (EGCG) is a green tea polyphenol that presents anticancer activities in multiple cancer cells, but no available report was addressed for the underling molecular mechanism of cytotoxic impacts on drug-resistant oral squamous cell carcinoma cells. In the present study, the inhibitory effects of EGCG were experienced on cisplatin-resistant oral cancer CAR cells. EGCG inhibited cell viability in a time- and concentration-dependent manner by a sulforhodamine B (SRB) assay. EGCG induced CAR cell apoptosis and autophagy by 4',6-diamidino-2-phenylindole (DAPI) dye, acridine orange (AO) staining and green fluorescent protein (GFP)-tagged LC3B assay, respectively. EGCG also significantly enhanced caspase-9 and caspase-3 activities by caspase activity assay. EGCG markedly increased the protein levels of Bax, cleaved caspase-9, cleaved caspase-3, Atg5, Atg7, Atg12, Beclin-1, and LC3B-II, as well as significantly decreased the expression of Bcl-2, phosphorylated AKT (Ser473) and phosphorylation of STAT3 on Tyr705 by western blotting in CAR cells. Importantly, the protein and gene expression of multidrug resistance 1 (MDR1) were dose-dependently inhibited by EGCG. Overall, downregulation of MDR1 levels and alterations of AKT/STAT3 signaling contributed to EGCG-induced apoptosis and autophagy in CAR cells. Based on these results, EGCG has the potential for therapeutic effect on oral cancer and may be useful for long-term oral cancer prevention in the future. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 845-855, 2017.

Structure Elucidation of Procyanidins Isolated from Rhododendron formosanum and Their Anti-Oxidative and Anti-Bacterial Activities.

Rhododendron formosanum is an endemic species distributed in the central mountains of Taiwan. In this study, the biological activities of major procyanidins isolated from the leaf extract of R. formosanum were investigated. Four compounds, including two procyanidin dimers, procyanidin A1 (1) and B3 (2), and two procyanidin trimmers, procyanidin C4 (4) and cinnamtannin D1 (5), were isolated and identified on the basis of spectroscopic data. The structure of a new procyanidin dimer, rhodonidin A (3), was elucidated by 2D-NMR, CD spectrum and MS. The procyanidin trimmers and rhodonidin A are reported for the first time in Ericaceae. The biological activities of these procyanidins were evaluated using anti-bacterial and anti-oxidative assays. Only the new compound 3 demonstrated strong anti-bacterial activity against Staphylococcus aureus at an MIC value of 4 µg/mL. All compounds showed pronounced antioxidant activities and the activities are enhanced as the amount of OH groups in procyanidins increased. In conclusion, the pleiotropic effects of procyanidins isolated from the leaves of R. formosanum can be a source of promising compounds for the development of future pharmacological applications.

Biological activity of oleanane triterpene derivatives obtained by chemical derivatization.

Nine new derivatives of oleanane triterpenoids isolated from Fatsia polycarpa Hayata were synthesized through chemical transformations. Acetylation was effected by reaction with acetic anhydride in pyridine to afford compounds 1-5, while compound 6 was obtained using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC·HCl) in CH2Cl2. The others derivatives 7-9 were obtained in reactions of the corresponding triterpenoids with EDC·HCl, 4-N,N-dimethylaminopyridine hydrochloride and 4-N,N-dimethylaminopyridine in CH2Cl2. The structures of 1-9 were elucidated from extensive spectroscopic and HRESIMS data, while the structure of 9 was further confirmed by X-ray diffraction analysis. The cytotoxic, anti-hepatitis B virus (HBV), antibacterial, hypoglycaemic and Wnt signaling activities of these derivatives were evaluated in vitro.

Ex Vivo Model to Evaluate the Antibacterial and Anti-Inflammatory Effects of Gelatin-Tricalcium Phosphate Composite Incorporated with Emodin and Lumbrokinase for Bone Regeneration.

Tricalcium phosphate (TCP) has gained attention due to its interconnected porous structures which promote fibrovascular invasion and bony replacement. Moreover, when gelatin is added and crosslinked with genipin (GGT), TCP exhibits robust biocompatibility and stability, making it an excellent bone substitute. In this study, we incorporated emodin and lumbrokinase (LK) into GGT to develop an antibacterial biomaterial. Emodin, derived from various plants, possesses antibacterial and anti-inflammatory properties. LK comprises proteolytic enzymes extracted from the earthworm Lumbricus rubellus and exhibits fibrinolytic activity, enabling it to dissolve biofilms. Additionally, LK stimulates osteoblast activity while inhibiting osteoclast differentiation. GGT was combined with emodin and lumbrokinase to produce the GGTELK composite. The biomedical effects of GGTELK were assessed through in vitro assays and an ex vivo bone defect model. The GGTELK composite demonstrated antibacterial properties, inhibiting the growth of S. aureus and reducing biofilm formation. Moreover, it exhibited anti-inflammatory effects by reducing the secretion of IL-6 in both in vivo cell experiments and the ex vivo model. Therefore, the GGTELK composite, with its stability, efficient degradation, biocompatibility, and anti-inflammatory function, is expected to serve as an ideal bone substitute.

Ceramide and Toll-like receptor 4 are mobilized into membrane rafts in response to Helicobacter pylori infection in gastric epithelial cells.

Helicobacter pylori infection is thought to be involved in the development of several gastric diseases. Two H. pylori virulence factors (vacuolating cytotoxin A and cytotoxin-associated gene A) reportedly interact with lipid rafts in gastric epithelial cells. The role of Toll-like receptor (TLR)-mediated signaling in response to H. pylori infection has been investigated extensively in host cells. However, the receptor molecules in lipid rafts that are involved in H. pylori-induced innate sensing have not been well characterized. This study investigated whether lipid rafts play a role in H. pylori-induced ceramide secretion and TLR4 expression and thereby contribute to inflammation in gastric epithelial cells. We observed that both TLR4 and MD-2 mRNA and protein levels were significantly higher in H. pylori-infected AGS cells than in mock-infected cells. Moreover, significantly more TLR4 protein was detected in detergent-resistant membranes extracted from H. pylori-infected AGS cells than in those extracted from mock-infected cells. However, this effect was attenuated by the treatment of cells with cholesterol-usurping agents, suggesting that H. pylori-induced TLR4 signaling is dependent on cholesterol-rich microdomains. Similarly, the level of cellular ceramide was elevated and ceramide was translocated into lipid rafts after H. pylori infection, leading to interleukin-8 (IL-8) production. Using the sphingomyelinase inhibitor imipramine, we observed that H. pylori-induced TLR4 expression was ceramide dependent. These results indicate the mobilization of ceramide and TLR4 into lipid rafts by H. pylori infection in response to inflammation in gastric epithelial cells.

Identification of Escherichia coli genes associated with urinary tract infections.

Escherichia coli is the most common cause of urinary tract infections (UTIs). E. coli genes epidemiologically associated with UTIs are potentially valuable in developing strategies for treating and/or preventing such infections as well as differentiating uropathogenic E. coli from nonuropathogenic E. coli. To identify E. coli genes associated with UTIs in humans, we combined microarray-based and PCR-based analyses to investigate different E. coli source groups derived from feces of healthy humans and from patients with cystitis, pyelonephritis, or urosepsis. The cjrABC-senB gene cluster, sivH, sisA, sisB, eco274, and fbpB, were identified to be associated with UTIs. Of these, cjrABC-senB, sisA, sisB, and fbpB are known to be involved in urovirulence in the mouse model of ascending UTI. Our results provide evidence to support their roles as urovirulence factors in human UTIs. In addition, the newly identified UTI-associated genes were mainly found in members of phylogenetic groups B2 and/or D.

Solanum lyratum Extracts Induce Extrinsic and Intrinsic Pathways of Apoptosis in WEHI-3 Murine Leukemia Cells and Inhibit Allograft Tumor.

We investigated the molecular mechanisms of cell cycle arrest and apoptotic death induced by Solanum lyratum extracts (SLE) or diosgenin in WEHI-3 murine leukemia cells in vitro and antitumor activity in vivo. Diosgenin is one of the components of SLE. Our study showed that SLE and diosgenin decreased the viable WEHI-3 cells and induced G(0)/G(1) phase arrest and apoptosis in concentration- or time-dependent manners. Both reagents increased the levels of ROS production and decreased the mitochondrial membrane potential (ΔΨ(m)). SLE- and diosgenin-triggered apoptosis is mediated through modulating the extrinsic and intrinsic signaling pathways. Intriguingly, the p53 inhibitor (pifithrin-α), anti-Fas ligand (FasL) mAb, and specific inhibitors of caspase-8 (z-IETD-fmk), caspase-9 (z-LEHD-fmk), and caspase-3 (z-DEVD-fmk) blocked SLE- and diosgenin-reduced cell viability of WEHI-3 cells. The in vivo study demonstrated that SLE has marked antitumor efficacy against tumors in the WEHI-3 cell allograft model. In conclusion, SLE- and diosgenin-induced G(0)/G(1) phase arrest and triggered extrinsic and intrinsic apoptotic pathways via p53 activation in WEHI-3 cells. SLE also exhibited antitumor activity in vivo. Our findings showed that SLE may be potentially efficacious in the treatment of leukemia in the future.

Capsaicin induces apoptosis in SCC-4 human tongue cancer cells through mitochondria-dependent and -independent pathways.

Although there have been advances in the fields of surgery, radiotherapy, and chemotherapy of tongue cancer, the cure rates are still not substantially satisfactory. Capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide) is the major pungent ingredient of hot chili pepper and has been reported to have an antitumor effect on many human cancer cell types. The molecular mechanisms of the antitumor effect of capsaicin are not yet completely understood. Herein, we investigated whether capsaicin induces apoptosis in human tongue cancer cells. Capsaicin decreased the percentage of viable cells in a dose-dependent manner in human tongue cancer SCC-4 cells. In addition, capsaicin produced DNA fragmentation, decreased the DNA contents (sub-G1 phase), and induced G0/G1 phase arrest in SCC-4 cells. We demonstrated that capsaicin-induced apoptosis is associated with an increase in reactive oxygen species and Ca²âº generations and a disruption of the mitochondrial transmenbrane potential (ΔΨ(m)). Treatment with capsaicin induced a dramatic increase in caspase-3 and -9 activities, as assessed by flow cytometric methods. A possible mechanism of capsaicin-induced apoptosis is involved in the activation of caspase-3 (one of the apoptosis-executing enzyme). Confocal laser microscope examination also showed that capsaicin induced the releases of AIF, ATF-4, and GADD153 from mitochondria of SCC-4 cells.

Helicobacter pylori Targets in AGS Human Gastric Adenocarcinoma: In Situ Proteomic Profiling and Systematic Analysis.

BACKGROUND/AIM: Helicobacter pylori, a gram-negative bacterium, causes chronic stomach diseases in humans. Heat shock proteins (HSPs) are involved in cell integrity, cell growth, and gastric mucosa colonization by H. pylori. This study aimed to investigate HSP expression levels in H. pylori-infected gastric adenocarcinoma AGS cells. MATERIALS AND METHODS: We determined protein expression levels using iTRAQ proteomics analysis. We analyzed the possible network interactions for H. pylori targets in AGS cells using the Ingenuity Pathway Analysis (IPA) software. RESULTS: H. pylori-infected AGS cells potentially targeted EIF2 and BAG2 signaling pathways to regulate cell physiology. In addition, after 3, 6, and 12 h of infection, western blotting revealed significantly decreased HSP70 and HSP105 expression. CONCLUSION: H. pylori decreases HSPs in AGS gastric adenocarcinoma cells, and this is associated with the regulation of EIF2 and BAG2 signaling pathways.

Association of EZH2 Genotypes With Oral Cancer Risk.

BACKGROUND/AIM: The over-expression of enhancer of zeste homolog 2 (EZH2) protein is found in oral cancer tissues. However, the genetic role of the enhancer of EZH2 in the etiology of oral cancer is unknown. The aim of this study was to evaluate the association of EZH2 genotypes with oral cancer risk among Taiwanese. MATERIALS AND METHODS: Three polymorphic variants of EZH2, rs887569 (C to T), rs41277434 (A to C), and rs3757441 (T to C), were analyzed regarding their association with oral cancer risk among 958 oral cancer patients and the same number of healthy controls by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). In addition, the interaction of EZH2 rs887569, rs41277434, and rs3757441 genotypes with personal behaviors such as smoking, alcohol drinking, and betel quid chewing were also examined. RESULTS: The EZH2 genotypes rs887569, rs41277434, and rs3757441, were not significantly associated with oral cancer risk (p for trend=0.1735, 0.5658, and 0.4606, respectively). The analysis of allelic frequency distribution also supported the findings that the variant alleles at EZH2 rs887569, rs41277434, and rs3757441 may not serve as determinants of oral cancer risk (all p>0.05). There was no interaction between EZH2 rs887569, rs41277434, or rs3757441 genotypes with personal smoking, alcohol drinking or betel quid chewing behaviors. CONCLUSION: EZH2 genotypes cannot predict oral cancer risk in Taiwan.

In Silico and In Vitro studies of taiwan chingguan yihau (NRICM101) on TNF-α/IL-1ß-induced human lung cells.

COVID-19 pandemic has been a global outbreak of coronavirus (SARS-CoV-2 virus) since 2019. Taiwan Chingguan Yihau (NRICM101) is the first traditional Chinese medicine (TCM) classic herbal formula and is widely used for COVID-19 patients in Taiwan and more than 50 nations. This study is to investigate in silico target fishing for the components of NRICM101 and to explore whether NRICM101 inhibits cytokines-induced normal human lung cell injury in vitro. Our results showed that network prediction of NRICM101 by a high throughput target screening platform showed that NRICM101 has multiple functions that may affect cytokine regulation to prevent human lung cell injury. In addition, NRICM101 revealed protective effects against TNF-α/IL-1ß-induced normal human lung HEL 299 cell injury through JNK and p38MAPK kinase signaling. Next-generation sequencing (NGS) analysis of NRICM101 on TNF-α/IL-1ß-injured HEL 299 cells indicated that inflammatory pathway, cell movement of macrophages, cellular infiltration by macrophages, and Th1/Th2 immuno-regulation pathways were included. Thus, NRICM101 is a therapeutic agent, and it can improve COVID-19 syndrome to confer beneficial effects through multiple targeting and multiple mechanisms.

Oleanane-type triterpenoids from the leaves and twigs of Fatsia polycarpa.

Seven new oleanane-type triterpenoids (1-7), named fatsicarpains A-G, and the known compounds 3α-hydroxyolean-11,13(18)-dien-28-oic acid (8) and 3α-hydroxyolean-11-en-28,13ß-olide (9) were isolated from the leaves and twigs of Fatsia polycarpa on the basis of bioassay-guided fractionation. The structures of compounds 1-7 were elucidated through spectroscopic analyses and single-crystal X-ray crystallography of 1, 8, and 9. Cytotoxicity against HepG2 2.2.15 and AGS cells and antihepatitis B virus (HBV) and antibacterial activities of 1-9 were also evaluated in vitro.

Antagonistic Activities of Lactobacillus rhamnosus JB3 Against Helicobacter pylori Infection Through Lipid Raft Formation.

Helicobacter pylori is a Gram-negative pathogen that can increase the risk of stomach cancer in infected patients. H. pylori exploits lipid rafts to infect host cells. Infection triggers clustering of Lewis x antigen (Lex) and integrins in lipid rafts to facilitate H. pylori adherence to the gastric epithelium. H. pylori infection can be treated with probiotics containing lactic acid bacteria that offer numerous benefits to the host while lacking the side effects associated with antibiotic therapy. Previously, we showed that the cell-free supernatant (CFS) derived from Lactobacillus rhamnosus JB3 (LR-JB3) at a multiplicity of infection (MOI) of 25 attenuated the pathogenicity of H. pylori. In this study, we established a mucin model to simulate the gastric environment and to further understand the influence of mucin on the pathogenesis of H. pylori. Porcine stomach mucin dramatically upregulated H. pylori virulence gene expression, including that of babA, sabA, fucT, vacA, hp0499, cagA, and cagL, as well as the adhesion and invasion ability of H. pylori and induced increased levels of IL-8 in infected-AGS cells. The CFS derived from LR-JB3 at a MOI of 25 reduced the expression of H. pylori sabA, fucT, and hp0499 in mucin, as well as that of the Lex antigen and the α5ß1 integrin in AGS cells during co-cultivation. These inhibitory effects of LR-JB3 also suppressed lipid raft clustering and attenuated Lewis antigen-dependent adherence, type IV secretion system-mediated cell contact, and lipid raft-mediated entry of VacA to host cells. In conclusion, LR-JB3 could affect H. pylori infection through mediating lipid raft formation of the host cells. The currently unknown cues secreted from LR-JB3 are valuable not only for treating H. pylori infection, but also for treating diseases that are also mediated by lipid raft signaling, such as cancer and aging-associated and neurodegenerative conditions.