Alginate and its Two Components Acted Differently Against Dopaminergic Neuronal Loss in Parkinson's Disease Mice Model.

SCOPE: This study aims to investigate and compare the potentially neuroprotective effects and underlying mechanisms for brown seaweed polysaccharides (PS) of Alginate (Alg) and its two components, including polymannuronic acid (PM) and polyguluronic acid (PG), against Parkinson's disease (PD) pathogenesis. METHODS AND RESULTS: Model mice of PD are pretreated with Alg or PM or PG, separately via oral gavage once per day for four weeks. Our results found PM improved motor functions of PD mice, but Alg or PG did not. PM or PG, but not Alg, can prevent dopaminergic neuronal loss by increasing tyrosine hydroxylase (TH) expressions in midbrain of PD mice. The neuroprotective effects of PM rely on its anti-inflammation effects and its ability to improve striatal neurotransmitters (serotonin (5-HT) and 5-hydroxyindole acetic acid (5-HIAA)) levels in PD mice. PM inhibits inflammation, but PG or Alg induces inflammation in systemic circulation of PD mice. The neuroprotection provided by PG might be related to its ability to increase striatal neurotransmitter of 5-hydroxyindole acetic acid levels in PD mice. CONCLUSION: PM plays better than PG to provide neuroprotection, but Alg did not show any neuroprotection against PD. Alg and its two components acted differently in preventing dopaminergic neuronal loss in PD mice.

Polymannuronic acid prevents dopaminergic neuronal loss via brain-gut-microbiota axis in Parkinson's disease model.

The study aims to investigate the potentially neuroprotective effects and underlying mechanisms for brown seaweed polysaccharide of polymannuronic acid (PM) against Parkinson's disease (PD) pathogenesis. PD model mice were pretreated with PM via oral gavage once per day for 4 weeks and the preventative effects of PM against neuronal loss together with its modulation on brain-gut-microbiota axis were systematically explored. The results showed PM administration improved motor functions by preventing dopaminergic neuronal loss in the substantia nigra pars compacta (SNpc) and enhanced contents of striatal homovanillic acid (HVA), serotonin (5-HT), 5-hydroxyindole acetic acid (5-HIAA) and γ-aminobutyric acid (GABA) in PD mice. PM significantly alleviated inflammation in gut, brain and systemic circulation as shown by reduced levels or expressions of pro-inflammatory cytokines concurrently and inhibited mitogen-activated protein kinases (MAPK) signaling pathway in mice colon. Meanwhile, PM greatly improved integrity of intestinal barrier and blood brain barrier (BBB) as indicated by increased expressions of tight junction associated proteins in both mice colon and SNpc. Further studies indicated PM treatment resulted in changes of gut microbial compositions, together with great alterations of digestion and metabolism of dietary proteins and fats, which led to surge increase of fecal short chain fatty acids (SCFAs) in the colon of PD mice. In conclusion, pre-administration of PM could provide neuroprotective effects against PD pathogenesis by suppressing inflammation in gut, brain and systemic circulation, and by improving integrity of intestinal barrier and BBB. PM might modulate brain-gut-microbiota axis, at least in part, via gut microbiota derived SCFAs as mediators.

Native κ-carrageenan induced-colitis is related to host intestinal microecology.

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, has gradually emerged as a public health challenge worldwide. Carrageenan is a popular food additive that has been in use for decades. However, controversy exists regarding to the safety of carrageenan due to its exacerbation of colitis in experimental models. In this study, we studied the effects of vehicle and host intestinal microflora on carrageenan inflammatory properties in C57BL/6 J mice. We found that in high-fat diet model, native carrageenan in drinking water increased the disease activity index (DAI), myeloperoxidase (MPO) activity and the mRNA expression of TLR4 in colon, whereas carrageenan-supplemented diet has no visible effects. However, no signs of colitis were observed under low-fat diet regardless of the mode of vehicle used. Moreover, we discovered that carrageenan-induced colitis in high-fat diet model was robustly correlated with changes in the composition of gut microbiota, specifically Alistipes finegoldii and Bacteroides acidifaciens. Hence, we propose that the inflammatory property of carrageenan is influenced greatly by its intake form via modification of host intestinal microecology.

A Pilot Study on Anti-Obesity Mechanisms of Kappaphycus Alvarezii: The Role of Native κ-Carrageenan and the Leftover Sans-Carrageenan Fraction.

Kappaphycus is a commercially important edible red alga widely cultivated for carrageenan production. Here, we aimed to investigate the anti-obesity mechanism of Kappaphycus alvarezii by comparing the effects of whole seaweed (T), extracted native κ-carrageenan (CGN), and the leftover fraction sans-carrageenan (SCGN) supplementations (5%, w/w) on diet-induced obese C57BL/6J mice. A high-fat diet induced both a raised body fat percentage and serum cholesterol level, increased adipocytes size, abnormal levels of adipocytokines, and promoted gut dysbiosis. Our results showed that, overall, both CGN and SCGN were more effective in reversing obesity and related metabolic syndromes to normal levels than T. Furthermore, these findings suggested that CGN- and SCGN-modulated gut dysbiosis induced by a high-fat diet, which may play an influencing role in adiponectin dysregulation. Our data also showed some evidence that CGN and SCGN have distinct effects on selected genes involved in lipid metabolism. In conclusion, both κ-carrageenan and SCGN have novel anti-obesity potential with possible different mechanisms of action.

Effects of curcumin-based photodynamic treatment on the storage quality of fresh-cut apples.

Photodynamic treatment (PDT) is an innovative technology with non-thermal and environmentally sound merits, but the evaluation on the storage qualities of fresh produce was scarce. In this study, the effects of curcumin-based PDT on the quality of fresh-cut 'Fuji' apple slices during storage at 4 °C were investigated. The impacts on the survival of Escherichia coli, color and weight loss were examined under different curcumin concentrations, illumination time or incubation time. Curcumin-based photodynamic inactivation of E. coli on the surface of apple slices reached 0.95 log. Curcumin-based PDT was proven to prevent browning and weight loss. Additionally, PDT significantly reduced the activity of polyphenol oxidase and peroxidases to 48% and 51%, respectively. Moreover, there were few negative changes in total phenolic, ascorbic acid content and anti-oxidant activity of the treated apples. These results indicated that curcumin-based PDT was a viable and promising non-thermal technology to preserve the quality of fresh produce.

Effect of photodynamic inactivation of Escherichia coli by hypericin.

The present study has focused on the effects of hypericin (Hyp) based photodynamic inactivation (PDI) of Escherichia coli (E. coli). To evaluate the efficiency of Hyp based PDI of E. coli, single factor experiments and response surface optimization experiment were conducted to obtain the optimum parameter values (36 µM Hyp, 5.9 J cm-2 light dose: 16.4 mW cm-2, 60 W, 260 s, 590 nm and 68 min incubation time) and finally achieved a 4.1 log CFU mL-1 decrease of E. coli. Cell-Hyp interaction and intracellular reactive oxygen species (ROS) level were detected by fluorescence spectrometric photometer. Data indicated that Hyp possessed a strong ability to bind with cells. In addition, a significant increase was observed in intracellular ROS level after Hyp-based photosensitization treatment. Therefore, Hyp-based photosensitization seems to be a promising method to efficiently inactivate E. coli. It is expected to be a safe, efficient, low cost and practical method which can be applied in the field of food safety.

Transcriptome analysis revealed anti-obesity effects of the Sodium Alginate in high-fat diet -induced obese mice.

Human obesity and overweight, caused by accumulated of fat, is the most commonly phenomenon from all over the world, especially in Western countries and Chinese mainland during the past three decades. Sodium Alginate, a polysaccharide extracted from brown seaweeds, has been proved its strong ability on body weight loss and anti-inflammatory response. However, no studies have been explored the effects of Sodium Alginate on colonic transcriptome, especially in obese individuals. Therefore, the current study was designed to detect whether Sodium Alginate could remit obesity and ease chronic metabolism disease through strengthening the bio-functionality of the lower intestine, particularly in colon. The data showed after Sodium Alginate gavaged for four weeks, the body weight, fat accumulation, triglyceride and total cholesterol were ameliorated in high fat diet induced obese mice. Sodium Alginate also improved the blood glucose level and lipopolysaccharides in serum. Furthermore, data from RNA sequence indicated that there were significantly changes in several genes, which involved in lipid metabolism and carbohydrate metabolism. In conclusion, these results suggested that Sodium Alginate could effectively suppress obesity and obesity related metabolic syndromes, due to the colonic transcriptome changes.

Polymannuronic acid ameliorated obesity and inflammation associated with a high-fat and high-sucrose diet by modulating the gut microbiome in a murine model.

Polymannuronic acid (PM), one of numerous alginates isolated from brown seaweeds, is known to possess antioxidant activities. In this study, we examined its potential role in reducing body weight gain and attenuating inflammation induced by a high-fat and high-sucrose diet (HFD) as well as its effect on modulating the gut microbiome in mice. A 30-d PM treatment significantly reduced the diet-induced body weight gain and blood TAG levels (P2·0). PM also had a profound impact on the microbial composition in the gut microbiome and resulted in a distinct microbiome structure. For example, PM significantly increased the abundance of a probiotic bacterium, Lactobacillus reuteri (log10 LDA score>2·0). Together, our results suggest that PM may exert its immunoregulatory effects by enhancing proliferation of several species with probiotic activities while repressing the abundance of the microbial taxa that harbor potential pathogens. Our findings should facilitate mechanistic studies on PM as a potential bioactive compound to alleviate obesity and the metabolic syndrome.

Palmatine hydrochloride mediated photodynamic inactivation of breast cancer MCF-7 cells: Effectiveness and mechanism of action.

Breast cancer is one of the commonest malignant tumors threatening to women. The present study aims to investigate the effect of photodynamic action of palmatine hydrochloride (PaH), a naturally occurring photosensitizer isolated from traditional Chinese medicine (TCM), on apoptosis of breast cancer cells. Firstly, cellular uptake of PaH in MCF-7 cells was measured and the cytotoxicity of PaH itself on breast cancer MCF-7 cells was estimated using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Subcellular localization of PaH in MCF-7 cells was observed using confocal laser scanning microscopy (CLSM). For photodynamic treatment, MCF-7 cells were incubated with PaH and then irradiated by visible light (470nm) from a LED light source. Photocytotoxicity was investigated 24h after photodynamic treatment using MTT assay. Cell apoptosis was analyzed 18h after photodynamic treatment using flow cytometry with Annexin V/PI staining. Nuclear was stained using Hoechst 33342 and observed under a fluorescence microscope. Intracellular production of reactive oxygen species (ROS) was studied by measuring the fluorescence of 2, 7-dichlorofluorescein (DCF) using a flow cytometry. Results showed that PaH treatment alone had no or minimum cytotoxicity to MCF-7 cells after incubation for 24h in the dark. After incubation for 40min, the cellular uptake of PaH reached to the maximum, and PaH mainly located in mitochondria and endoplasmic reticulum of MCF-7 cells. Photodynamic treatment of PaH demonstrated a significant photocytotoxicity on MCF-7 cells, induced remarkable cell apoptosis and significantly increased intracellular ROS level. Our findings demonstrated that PaH as a naturally occurring photosensitizer induced cell apoptosis and significantly killed MCF-7 cells.

Photodynamic effect of curcumin on Vibrio parahaemolyticus.

Vibrio parahaemolyticus (V. parahaemolyticus) is currently a major cause of bacterial diarrhoea associated with seafood consumption. The objective of this study was to determine the inactivation effect of curcumin-mediated photodynamic action on V. parahaemolyticus. First of all, V. parahaemolyticus suspended in PBS buffer was irradiated by a visible light from a LED light source with an energy density of 3.6J/cm(2). Colony forming units (CFU) were counted and the viability of V. parahaemolyticus cells was calculated after treatment. Singlet oxygen ((1)O2) production after photodynamic action of curcumin was evaluated using 9,10-Anthracenediyl-bis (methylene) dimalonic acid (ADMA). Bacterial outer membrane protein was extracted and analyzed using electrophoresis SDS-PAGE. DNA and RNA of V. parahaemolyticus were also extracted and analyzed using agarose gel electrophoresis after photodynamic treatment. Finally, the efficacy of photodynamic action of curcumin was preliminarily evaluated in the decontamination of V. parahaemolyticus in oyster. Results showed that the viability of V. parahaemolyticus was significantly decreased to non-detectable levels over 6.5-log reductions with the curcumin concentration of 10 and 20µM. Photodynamic action of curcumin significantly increased the singlet oxygen level with the curcumin concentration of 10µM. Notable damage was found to bacterial outer membrane proteins and genetic materials after photodynamic treatment. Photodynamic action of curcumin reduced the number of V. parahaemolyticus contaminating in oyster to non-detectable level. Our findings demonstrated that photodynamic action of curcumin could be a potentially good method to inactivate Vibrio parahaemolyticus contaminating in oyster.

Photodynamic action of palmatine hydrochloride on colon adenocarcinoma HT-29 cells.

Palmatine hydrochloride (PaH) is a natural active compound from a traditional Chinese medicine (TCM). The present study aims to evaluate the effect of PaH as a new photosensitizer on colon adenocarcinoma HT-29 cells upon light irradiation. Firstly, the absorption and fluorescence spectra of PaH were measured using a UV-vis spectrophotometer and RF-1500PC spectrophotometer, respectively. Singlet oxygen ((1)O2) production of PaH was determined using 1, 3-diphenylisobenzofuran (DPBF). Dark toxicity of PaH was estimated using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Cellular uptake of PaH in HT-29 cells was detected at different time intervals. Subellular localization of PaH in HT-29 cells was observed using confocal laser fluorescence microscopy. For photodynamic treatment, HT-29 cells were incubated with PaH and then irradiated by visible light (470nm) from a LED light source. Photocytotoxicity was investigated 24h after photodynamic treatment using MTT assay. Cell apoptosis was observed 18h after photodynamic treatment using a flow cytometry with Annexin V/PI staining. Results showed that PaH has an absorption peak in the visible region from 400nm to 500nm and a fluorescence emission peak at 406nm with an excitation wavelength of 365nm. PaH was activated by the 470nm visible light from a LED light source to produce (1)O2. Dark toxicity showed that PaH alone treatment had no cytotoxicity to HT-29 cancer cells and NIH-3T3 normal cells after incubation for 24h. After incubation for 40min, the cellular uptake of PaH reached to the maximum and PaH was located in mitochondria. Photodynamic treatment of PaH demonstrated a significant photocytotoxicity on HT-29 cells. The rate of cell death increased significantly in a PaH concentration-dependent and light dose-dependent manner. Further evaluation revealed that the early and late apoptotic rate of HT-29 cells increased remarkably up to 21.54% and 5.39% after photodynamic treatment of PaH at the concentration of 5µM and energy density of 10.8J/cm(2). Our findings demonstrated that PaH as a naturally occurring photosensitizer has potential in photodynamic therapy on colon adenocarcinoma.

The effect of a novel photodynamic activation method mediated by curcumin on oyster shelf life and quality.

In this paper, the effect of photodynamic method mediated by curcumin (PDT) on the shelf life and quality of pacific oysters during storage at 5±1°C were analyzed. In our previous study we investigated the optimal treatment conditions of photodynamic method mediated by curcumin to sterilization were 10uM photosensitizer concentration and 5.4J/cm2 light energy density. Under these conditions, the effect of a novel photodynamic activation method mediated by curcumin on oyster shelf life and quality was researched. The total bacterial counts, TVB-N content and sensory analysis were used to evaluate the effects on oyster shelf life. The oyster shelf life was prolonged from 8days to 12days after photodynamic treatment and the oysters in the treatment group displayed notable odor retention, produced fewer odor corrupting substances when the control group oysters reached the end of their shelf life (day 8). Texture, free amino acid contents and fatty acid levels were applied to estimate the quality of the treated oysters. The texture had no significant change after treated with PDT. At the end of oyster shelf life, compared PDT group (PDT) with control group (control), total free amino acid contents (control: 234.30mg/100g, PDT: 813.02mg/100g) was higher and free fatty acid levels (control: 0.071mEq/L, PDT: 0.0455mEq/L) displayed lower in PDT group. This indicated that the treated oysters oxidized minimally, decayed slowly, decomposed fewer nutrients and had lower metabolic levels of spoilage microorganisms. PDT has a positive effect on prolonging oyster shelf life and its quality.

Virucidal efficacy of treatment with photodynamically activated curcumin on murine norovirus bio-accumulated in oysters.

Norovirus (NoV) is one of the most important seafood- and water-borne viruses, and is a major cause of acute gastroenteritis outbreaks. In the present study we investigated the effect of curcumin as a sensitizer to photodynamic treatment both in buffer and in oysters against murine norovirus 1 (MNV-1), a surrogate of NoV. MNV-1 cultured in buffer and MNV-1 bio-accumulated in oysters were irradiated with a novel LED light source with a wavelength of 470nm and an energy of 3.6J/cm(2). Inactivation of MNV-1 was investigated by plaque assays. After virus was extracted from the gut of oysters treated over a range of curcumin concentrations, the ultrastructural morphology of the virus was observed using electron microscopy, and the integrity of viral nucleic acids and stability of viral capsid proteins were also determined. Results showed that the infectivity of MNV-1 was significantly inhibited by 1-3logPFU/ml, with significant damage to viral nucleic acids in a curcumin dose-dependent manner after photodynamic activation. Virus morphology was altered after the photodynamic treatment with curcumin, presumably due to the change of the viral capsid protein structures. The data suggest that treatment of oysters with photodynamic activation of curcumin is a potentially efficacious and cost-effective method to inactivate food-borne NoV. Further studies are necessary to evaluate the toxicology of this approach in detail and perform sensory evaluation of the treated product.

Establishment of a functional secretory IgA transcytosis model system in vitro for functional food screening.

A characteristic mucosal immune response involves the production of antigen-specific secretory immunoglobulin A (SIgA) antibodies. In order to study transcytosis by mimicking the SIgA secretion and to screen for SIgA secretion-promoting substances, we developed a model system of a transfected Madin-Darby canine kidney (MDCK) cell line that expresses the human polymeric immunoglobulin receptor (pIgR). We thus isolated the human dIgA (dimeric IgA)/pIgA (polymeric IgA) complex as the binding ligands. In the present study, a recombinant vector encoding the human pIgR gene was constructed and infected into MDCK cells. Following reverse transcription polymerase chain reaction (RT-PCR), immunoblotting, and immunofluorescence staining, we confirmed that pIgR was expressed in the transfectant MDCK-pIgR cells and was located at the basolateral side of the cell surface. We also confirmed the coexistence of the dIgA/pIgA complex in the IgA myeloma serum. The covalent dIgA/pIgA complex was then isolated from the serum of an IgA multiple myeloma patient using an ÄKTA purifier operation system with a HiPrep 16/60 Sephacryl S-300 HR column, in order to utilize the complex as transcytosis ligands for human pIgR. Finally, we confirmed the uptake of the isolated human dIgA/pIgA complex into MDCK-pIgR cells. We demonstrated that the human dIgA/pIgA complex was transcytosed into the apical side of the monolayer cells. Therefore, our MDCK-human pIgR cell transcytosis model is an operational system and can be used for screening functional food components that promote dIgA/pIgR transcytosis as well as SIgA secretion.

Dietary squid ink polysaccharide induces goblet cells to protect small intestine from chemotherapy induced injury.

Gastrointestinal mucositis induced by chemotherapy is associated with alterations of intestinal barrier function due to the potential damage induced by anti-cancer drugs on the epithelial cells. Goblet cells, an important epithelial lining in the intestine, contribute to innate immunity by secreting mucin glycoproteins. Employing a mouse model of chemotherapy induced intestinal mucosal immunity injury by cyclophosphamide, we demonstrated for the first time that polysaccharide from the ink of Ommastrephes bartramii (OBP) enhanced Cyto18, which is a mucin expression in goblet cells. The up-regulation of mucins by OBP relied on the augmented quantity of goblet cells, but not on the changes in the ultrastructure of endoplasmic reticulum (ER). Our results may have important implications for enhanced immunopotentiation function of functional OBP on intestinal mucosal immunity against intestinal disorders involving inflammation and infection.

Detection of noroviruses in shellfish and semiprocessed fishery products from a Belgian seafood company.

Shellfish have been implicated in norovirus (NoV) infection outbreaks worldwide. This study presents data obtained from various batches of shellfish and fishery products from a Belgian seafood company over a 6-month period. For the intact shellfish (oysters, mussels, and clams), 21 of 65 samples from 12 of 34 batches were positive for NoVs; 9 samples contained quantitative NoV levels at 3,300 to 14,300 genomic copies per g. For the semiprocessed fishery products (scallops and common sole rolls with scallop fragments), 29 of 36 samples from all eight batches were positive for NoVs; 17 samples contained quantitative NoV levels at 200 to 1,800 copies per g. This convenience study demonstrated the performance and robustness of the reverse transcription quantitative PCR detection and interpretation method and the added value of NoV testing in the framework of periodic control of seafood products bought internationally and distributed by a Belgian seafood processing company to Belgian food markets.

Protective effects of cerebrosides from sea cucumber and starfish on the oxidative damage in PC12 cells.

Neurodegenerative disorders are a class of diseases that have been linked to apoptosis induced by elevated levels of reactive oxygen species (ROS). The present study was undertaken to explore the effect of sea cucumber cerebrosides (SCC) and starfish cerebrosides (SFC) on the hydrogen peroxide (H2O2) and tert-butyl hydroperoxide (t-BHP)-induced oxidative damage in PC12 cells. Cell viability, the leakage of lactate dehydrogenase (LDH), reactive oxygen species (ROS) level and superoxide dismutase (SOD) activity were determined for their effect on oxidative damage. Quantitative real-time PCR was investigated to analyze the mitochondrial genes expression. These results showed that both SCC and SFC decreased the leakage of LDH and intracellular ROS in a dose-dependent manner. SCC and SFC could also increase the SOD activity compared with the model groups. In H2O2 damage model, 400 µg/mL SCC increased the SOD activity by 79%, which was stronger than SFC. The results demonstrated that SCC and SFC exhibited the protective effects, which may be related to their antioxidant action. In addition, SCC and SFC dramatically increased the gene expression of B-cell lymphoma 2 (Bcl-2) but significantly decreased the gene expression of Cytochrome c, caspase9 and caspase3 compared with H2O2 or t-BHP treatment. These results suggested that SCC and SFC might exert a protective function against oxidative damage by inhibiting mitochondria-mediated apoptosis pathway. In conclusion, SCC and SFC played an important protective role in H2O2 and t-BHP-induced damage of PC12 cells, suggesting that the SCC and SFC may be a potential therapeutic agent against nervous system oxidative damage.

Multivalent immune complexes divert FcRn to lysosomes by exclusion from recycling sorting tubules.

The neonatal receptor for immunoglobulin G (IgG; FcRn) prevents IgG degradation by efficiently sorting IgG into recycling endosomes and away from lysosomes. When bound to IgG-opsonized antigen complexes, however, FcRn traffics cargo into lysosomes, where antigen processing can occur. Here we address the mechanism of sorting when FcRn is bound to multivalent IgG-opsonized antigens. We find that only the unbound receptor or FcRn bound to monomeric IgG is sorted into recycling tubules emerging from early endosomes. Cross-linked FcRn is never visualized in tubules containing the unbound receptor. Similar results are found for transferrin receptor, suggesting a general mechanism of action. Deletion or replacement of the FcRn cytoplasmic tail does not prevent diversion of trafficking to lysosomes upon cross-linking. Thus physical properties of the lumenal ligand-receptor complex appear to act as key determinants for sorting between the recycling and lysosomal pathways by regulating FcRn entry into recycling tubules.

Ds-echinoside A, a new triterpene glycoside derived from sea cucumber, exhibits antimetastatic activity via the inhibition of NF-κB-dependent MMP-9 and VEGF expressions.

Ds-echinoside A (DSEA), a non-sulfated triterpene glycoside, was isolated from the sea cucumber Pearsonothuria graeffei. In vitro and in vivo investigations were conducted on the effects of DSEA on tumor cell adhesion, migration, invasion, and angiogenesis. In this study, we found that DSEA inhibited the proliferation of human hepatocellular liver carcinoma cells Hep G2, with a half-maximal inhibitory concentration (IC50) of 2.65 µmol/L, and suppressed Hep G2 cell adhesion, migration, and invasion in a dose-dependent manner. DSEA also reduced tube formation of human endothelial cells ECV-304 on matrigel in vitro and attenuated neovascularization in the chick embryo chorioallantoic membrane (CAM) assay in vivo. Immunocytochemical analysis revealed that DSEA significantly decreased the expression of matrix metalloproteinase-9 (MMP-9), which plays an important role in the degradation of basement membrane in tumor metastasis and angiogenesis. DSEA also increased the protein expression level of tissue inhibitor of metalloproteinase-1 (TIMP-1), an important regulator of MMP-9 activation. From the results of Western blotting, the expressions of nuclear factor-kappa B (NF-κB) and vascular endothelial growth factor (VEGF) were found to be remarkably reduced by DSEA. These findings suggest that DSEA exhibits a significant anti-metastatic activity through the specific inhibition of NF-κB-dependent MMP-9 and VEGF expressions.

Expression of polymeric immunoglobulin receptor mRNA and protein in human paneth cells: Paneth cells participate in acquired immunity.

OBJECTIVE: Paneth cells are important effectors of intestinal innate immunity. It has been generally accepted that Paneth cells do not participate in the synthesis of polymeric immunoglobulin receptor (pIgR) or the secretion of immunoglobulin A (IgA) in the small intestine. However, we have previously shown that pIgR is specifically localized in Paneth cells of the rat small intestine. We therefore investigated the possibility that pIgR is also localized in human Paneth cells. METHODS: Double-labeled fluorescent immunohistochemistry and double-labeled fluorescent in situ hybridization were used to determine RNA and protein expression in normal human small intestine. RESULTS: Both pIgR mRNA and protein were colocalized with lysozyme in normal human Paneth cells. Furthermore, IgA was colocalized with lysozyme in the secretory granules of human Paneth cells. CONCLUSIONS: This is the first study to demonstrate that pIgR and IgA are colocalized in the secretory granules of human Paneth cells. These findings suggest that, in addition to their well-recognized role in innate immunity, Paneth cells are involved in IgA-mediated acquired immunity in the gastrointestinal tract. Furthermore, these results add to accumulating evidence that Paneth cells participate in intestinal inflammation.