In Vitro and In Vivo Antiglycation Effects of Connarus ruber Extract.

Accumulation of advanced glycation end products (AGEs) of the Maillard reaction has been implicated in the pathogenesis of diabetes and its complications. Connarus ruber has been used as a folk remedy for several diseases, including diabetes; however, its underlying mechanism has not yet been investigated. This study investigated the effects of C. ruber extract against glycation on collagen-linked AGEs in vitro and streptozotocin-induced diabetic rats (STZ-DM rats) in vivo. The antiglycation activities of C. ruber extract and aminoguanidine (AG) were examined using a collagen glycation assay kit. Nonfluorescent AGE, Nε-carboxymethyl lysine (CML), Nω-carboxymethyl arginine, and Nε-carboxyethyl lysine levels were measured via electrospray ionization-liquid chromatography-tandem mass spectrometry. The effect of the extract on the cytotoxicity of methylglyoxal (MG), a precursor of AGEs, was examined in HL60 cells. STZ-DM rats were treated with the extract for 4 wk, and the effect was assessed using biochemical markers in the serum and CML-positive cells in renal tissues. C. ruber extract dose-dependently inhibited the glycation of collagen and formation of nonfluorescent AGEs, which was comparable to AG, and it significantly attenuated MG-induced cytotoxicity in HL60 cells. Furthermore, the glycated albumin levels in STZ-DM rats decreased, the increase in serum lipid levels was reversed, and immunohistochemistry demonstrated that CML deposition in the glomerulus of STZ-DM rats significantly decreased. Although further studies are needed, C. ruber could be a potential therapeutic for preventing and progressing many pathological conditions, including diabetes.

Environmental Impact of Tributyltin-Resistant Marine Bacteria in the Indigenous Microbial Population of Tributyltin-Polluted Surface Sediments.

　We compared the TBT-resistant ability of resting cells prepared from isolates that formed colonies on nutrient agar plates containing 100 µM tributyltin (TBT) chloride, such as Photobacterium sp. TKY1, Halomonas sp. TKY2, and Photobacterium sp. NGY1, with those from taxonomically similar type strains. Photobacterium sp. TKY1 showed the highest ability among those three isolates. The number of surviving Photobacterium sp. TKY1 cells was hardly decreased after 1 h of exposure to 100 µM TBTCl, regardless of the number of resting cells in the range from 109.4 to 104.2 CFU mL-1. In such an experimental condition, the maximum number of TBT molecules available to associate with a single cell was estimated to be approximately 6.0 x 1011.8. Resting cells prepared from type strains Photobacterium ganghwense JCM 12487T and P. halotolerans LMG 22194T, which have 16S rDNA sequences highly homologous with those of Photobacterium sp. TKY1, showed sensitivity to TBT, indicating that TBT-resistant marine bacterial species are not closely related in spite of their taxonomic similarity. We also estimated the impact of TBT-resistant bacterial species to indigenous microbial populations of TBT-polluted surface sediments. The number of surviving TBT-sensitive Vibrio natriegens ATCC 14048T cells, 106.2±0.3 CFU mL-1, was reduced to 104.4±0.4 CFU mL-1 when TBT-resistant Photobacterium sp. TKY1 cells, 109.1±0.2 CFU mL-1, coexisted with 109.4±0.2 CFU mL-1 of V. natriegens ATCC 14048T cells in the presence of 100 µM TBTCl. These results indicate that the toxicity of TBT to TBT-sensitive marine bacterial populations might be enhanced when a TBT-resistant marine bacterial species inhabits TBT-polluted surface sediments.

Inhibitory effects of wasabi isothiocyanates on chemical mediator release in RBL-2H3 rat basophilic leukemia cells.

Wasabi is a plant of Japanese origin. It belongs to the family Brassicaceae and produces various isothiocyanates (ITCs). To clarify the type I allergies inhibited by wasabi ITCs, we investigated the inhibitory effect on chemical mediator release from dinitrophenylated bovine serum albumin (DNP-BSA)-stimulated RBL-2H3 rat basophilic leukemia cells. Allyl ITC (AITC), sec-butyl ITC (s-BuITC), and 3-butenyl ITC (3-BuITC), which have 3 or 4 carbon chains, inhibited histamine release but did not inhibit the release of leukotriene B4 (LTB4) or cysteinyl LTs (CysLTs). 4-Pentenyl ITC (4-PeITC) and 5-hexenyl ITC (5-HeITC), which have 5 or 6 carbon chains and an unsaturated bond at the end, inhibited LTB4 release but did not inhibit the release of histamine or CysLTs. 6-Methylthiohexyl ITC (6-MTITC), 6-methylsulfinylhexyl ITC (6-MSITC), and 6-methylsulfonylhexyl ITC (6-MSFITC), which have a sulfur atom inserted at the end of a 6-carbon chain, inhibited the release of histamine, LTB4, and CysLTs and the elevation in intracellular Ca(2+). These results suggest that wasabi ITCs inhibited type I allergies by inhibiting chemical mediator release and that the inhibitory effects on each chemical mediator were due to differences in the side chain structure of the wasabi ITCs.

Inhibitory effects of autolysate of Leuconostoc mesenteroides isolated from kimoto on melanogenesis.

We investigated the inhibitory effects of the autolysate of Leuconostoc mesenteroides, a lactic acid bacterium isolated from sake mash, on melanogenesis in B16F0 murine melanoma cells and a human skin model. The autolysate: induced a decrease in melanin content in B16F0 murine melanoma cells and a 17%, 36%, 41% and 58% decrease in the human skin model by the application of 0.125, 1.25, 6.25, and 12.5 mg/tissue in total; decreased tyrosinase activity to 71%, 46% and 29% of control in B16F0 cells with 0.1, 0.2 and 0.4 mg/ml-medium respectively, but did not inhibit tyrosinase activity under cell-free conditions; decreased amount of tyrosinase in a dose-dependent manner from 74% with 0.1 mg/ml to 33% with 0.4 mg/ml; and decreased amount of tyrosinase mRNA to 80-90% with 0.2-0.4 mg/ml-medium. As the decrease in tyrosinase mRNA levels could not fully account for the reduction in protein, we suggest that the autolysate had post-transcriptional effects rather than transcription inhibition. Our results indicate that the autolysate of L. mesenteroides has potential therapeutic use as an effective anti-melanogenic agent.

Anti-allergic effect of lactic acid bacteria isolated from seed mash used for brewing sake is not dependent on the total IgE levels.

Lactic acid bacteria (LAB) in fermented foods have attracted considerable attention recently as treatment options for allergic diseases, the incidence of which has been increasing worldwide. Five strains of LAB isolated from kimoto, the traditional seed mash used for brewing sake, were screened for the ability to suppress IgE-mediated hypersensitivity reaction. Leuconostoc mesenteroides and Lactobacillus sakei, the normal microflora in kimoto, significantly suppressed the reaction, but the contaminant Lactobacillus curvatus did not. Next, we examined the effect of L. sakei LK-117 on atopic dermatitis in the NC/Nga mouse model. LK-117 supplementation significantly reduced the development of atopic dermatitis-like skin lesions in a manner independent of the IgE plasma levels. In the in vitro intestinal model constructed using the human intestinal epithelial cell line Caco-2 and murine macrophage cell line RAW 264.7, treatment with L. sakei LK-117, but not L. curvatus, significantly upregulated TNF-α production from RAW264.7 cells. This result indicated that L. sakei on the apical side affected the macrophages on the basolateral side, and this organism may have the ability to improve allergy symptoms mediated by the intestinal immune system.

TLR ligands of Lactobacillus sakei LK-117 isolated from seed mash for brewing sake are potent inducers of IL-12.

Many studies have investigated the immunostimulatory effects of bacteria, such as the anti-allergic effects of lactic acid bacteria (LAB) and LAB-fermented milk. Importantly, these anti-allergic effects have been observed for both viable and nonviable bacteria. However, there are no reported immunological effects of LAB isolated from kimoto, the traditional yeast starter culture used for brewing sake, which also involves spontaneous lactate fermentation. In this study, we determined whether the Leuconostoc mesenteroides and Lactobacillus sakei bacterial strains obtained from kimoto affected the production of interleukin-12 (IL-12), an inducer of the T-helper type-1 immune response. By incubating autoclaved bacteria with J774.1 macrophage-like cells, we found that L. sakei LK-117 induced a sustained increase in IL-12p40 production. The IL-12-inducing ability of LK-117 was unaffected by anti-TLR2 neutralization and was entirely inhibited when the LK-117 cells were treated with RNase. When LK-117 cells were treated with M-1, an N-acetylmuramidase, at varying concentrations and for different periods of time, the ability of the bacteria to induce IL-12 decreased quickly. Although an active fraction could be prepared by chromatography from the soluble products of enzymolysis, the fraction's induction ability was <2% of that of intact organisms, and induction ability disappeared completely upon anti-TLR2 neutralization after treating the active fraction with RNase. These results suggest that single-stranded RNA released from cells that were disrupted by autoclaving might act as a TLR ligand and provide a novel mechanism in which heat-killed LAB could be used to regulate immune activity.

Adsorption of tributyltin by tributyltin resistant marine Pseudoalteromonas sp. cells.

The isolate, Pesudoalteromonas sp. TBT1, could grow to overcome the toxicity of tributyltin chloride (TBTCl) up to 30 microM in the absence of Cl(-) in the medium until the cells reached an exponential phase of growth. The viability, however, was reduced after the cells reached a stationary phase. The degradation products, such as dibutyltin (DBT) and monobutyltin (MBT), were not detected in the growth medium, indicating that the isolate has no ability to degrade TBT into less toxic DBT and MBT. Up to about 10(7.5) TBT molecules were adsorbed by a single cell. The observation of morphological changes with an electron microscope showed that the cell surface became wrinkled after exposure to the lethal concentration of 10 mM TBTCl. These results indicate that the resistance of the isolate toward the toxicity of TBTCl is not related to the unique cell surface, which seems to play an important role in preventing the diffusion of TBTCl into the cytoplasm.

Accelerator analysis of tributyltin adsorbed onto the surface of a tributyltin resistant marine Pseudoalteromonas sp. cell.

Tributyltin (TBT) released into seawater from ship hulls is a stable marine pollutant and obviously remains in marine environments. We isolated a TBT resistant marine Pseudoalteromonas sp. TBT1 from sediment of a ship's ballast water. The isolate (10(9.3 +/- 0.2) colony-forming units mL(-1)) adsorbed TBT in proportion to the concentrations of TBTCl externally added up to 3 mM, where the number of TBT adsorbed by a single cell was estimated to be 10(8.2). The value was reduced to about one-fifth when the lysozyme-treated cells were used. The surface of ethanol treated cells became rough, but the capacity of TBT adsorption was the same as that for native cells. These results indicate that the function of the cell surface, rather than that structure, plays an important role to the adsorption of TBT. The adsorption state of TBT seems to be multi-layer when the number of more than 10(6.8) TBT molecules is adsorbed by a single cell.

Rotenoids and flavonoids with anti-invasion of HT1080, anti-proliferation of U937, and differentiation-inducing activity in HL-60 from Erycibe expansa.

Principal rotenoids (deguelin, tephrosin, rotenone, and 12a-hydroxyrotenone) (3-30microM) isolated from the stems of Erycibe expansa significantly inhibited invasion of human fibrosarcoma HT1080 cells through Matrigel-coated filters and release of proMMPs-2 and 9. In addition, deguelin and tephrosin showed differentiation-inducing activity in human promyelocytic leukemia HL-60 cells. Furthermore, effects of various constituents isolated from the ethyl acetate-soluble fraction on proliferation of human leukemia U937 cells were examined. As a result, most of isoflavones and several flavans as well as rotenoids showed moderate or substantial anti-proliferative activities.

Lethality of shock pressures to a marine Vibrio sp. isolated from a ship's ballast water.

The lethal effects of shock pressure treatment on suspended Vibrio sp. cells were examined. Lethality of shock pressures to the Vibrio sp. cells increased with the increase in the values of maximum shock pressures generated in the cell suspension. When the value was around 114 MPa, the total number of colony-forming cells was reduced from 10(8.5+/-0.1) colony-forming units (CFU) to 10(3.3) - 10(3.4) CFU/ml, and complete loss of colony-forming ability was seen at the maximum value of 282 MPa. Almost all the cells could survive after the exposure to shock pressures including the maximum value of around 189 MPa in the presence of 2% sodium ascorbate (VitC-Na), whereas the total number of colony-forming cells was reduced to 10(1.6)-10(2.1) CFU/ml in the absence of VitC-Na. The surviving cells, however, showed sensitivity to 0.8% sodium cholate, a strong detergent. About 11% of cell-associated proteins had leaked out when the cells were exposed to lethal shock pressures including the maximum value of around 290 MPa in the absence of VitC-Na. These results indicate that the radicals generated in the cell suspension may be closely related to the loss of colony-forming ability of the Vibrio sp. cells. Damage to the outer membrane structure also seems to have occurred by the exposure to shock pressures.

Nuphar alkaloids with immediately apoptosis-inducing activity from Nuphar pumilum and their structural requirements for the activity.

The methanolic extract and its alkaloid fraction from the rhizomes of Nuphar pumilum showed cytotoxic effects on human leukemia cell (U937), mouse melanoma cell (B16F10), and human fibroblast (HT1080). Dimeric sesquiterpene thioalkaloids with the 6-hydroxyl group (6-hydroxythiobinupharidine, 6,6'-dihydroxythiobinupharidine, 6-hydroxythionuphlutine B) showed substantial cytotoxic activity at a concentration of 10 microM, but dimeric sesquiterpene thioalkaloids lacking the 6-hydroxyl group (thiobinupharidine, thionuphlutine B, 6'-hydroxythionuphlutine B, neothiobinupharidine, thionuphlutine B beta-sulfoxide, and neothiobinupharidine beta-sulfoxide) and monomeric sesquiterpene alkaloids (nupharidine, 7-epideoxynupharidine, and nupharolutine) showed weak activity. Next, apoptosis-inducing activity of a principal active constituent, 6-hydroxythiobinupharidine, on U937 was examined using morphological observation and DNA fragmentation assay (TUNEL method). Apoptosis of U937 was immediately observed within 1 h after treatment of 6-hydroxythiobinupharidine at 2.5-10 microM.

In vitro and in vivo anti-allergic activity of soy sauce.

Soy sauce (Shoyu) is a traditional fermented seasoning of Japan and available throughout the world. Polysaccharides were obtained from dialysate of Shoyu, and these Shoyu polysaccharides (SPS) were examined for anti-allergic activity in vitro and in vivo. The SPS originated from partially-degraded polysaccharides of soybeans by mold enzymatic hydrolyses, and Shoyu contained about 1% (w/v) SPS. First, the inhibitory effects of SPS on hyaluronidase, which is known to be related to inflammation and allergic responses, were as potent as those of an anti-allergic medicine, disodium cromoglycate. Second, SPS significantly inhibited the release of histamine from rat basophilic leukemia (RBL-2H3) cells, which had been induced by the antigen. Third, orally administered SPS had a significant suppressive effect on passive cutaneous anaphylaxis induced in the ears of mice. These results suggest that SPS may have anti-allergic activities, and soy sauce is a potentially promising seasoning for the treatment of allergic diseases through food.