Iwao Suzuki

Effect of orally administered β-glucan on macrophage function in mice

Abstract The effect of orally administered SSG, a β-1,3-glucan obtained from the culture filtrate of the fungus Sclerotinia sclerotiorum IFO 9395, on the function of peritoneal macrophages in CDF 1 mice was examined. Oral administration of SSG (20, 40, 80 or 160 mg/kg, daily for 10 consecutive days) enhanced the acid phosphates activity of peritoneal macrophages. The greatest enhancing effect was observed at 80 mg/kg of SSG. Relatively long periods of administration (more than 10 consecutive days) were needed to induce significant enhancing effects. Phagocytic activity, candidacidal activity, hydrogen peroxide (H 2 O 2 ) production and interleukin-1 (IL-1) production of peritoneal macrophages were also enhanced after the administration of SSG by the oral route (80 or 160 mg/kg). However, the durations of the activated state after completion of administration differed depending on the activity. Enhanced activity of lysosomal enzyme (acid phosphatase) was also shown in peritoneal macrophages taken from C3H/HeJ mice, which is a nonresponder strain to bacterial lipopolysaccharide (LPS). These results demonstrate that SSG given by the oral route can activate peritoneal macrophages in mice.

Enhancement of murine alveolar macrophage functions by orally administered β-glucan

The effect of orally administered SSG, a beta-1,3-glucan obtained from the culture filtrate of the fungus Sclerotinia sclerotiorum IFO 9395, on alveolar macrophage (AM) functions of CDF1 mice was examined. SSG administered orally (20, 40, 80 or 160 mg/kg) for 10 consecutive days enhanced the lysosomal enzyme activity of AM. The greatest enhancing effect was observed at 80 mg/kg of SSG. Multiple oral administrations of SSG (10 consecutive days) were needed to induce significant enhancing effects. Phagocytic activity and interleukin-1 (IL-1) production of AM were also augmented by oral administration of SSG, and the kinetics of the activated state differed depending on the kind of activity. However, H2O2 production of AM was not affected by SSG. Orally administered SSG also (40 or 80 mg/kg, 10 consecutive days) increased the number of AM and the greatest increment was observed 14 days after the first administration. On the other hand, the supernatant of Peyers patch (PP) cells from mice administered SSG (80 mg/kg) orally stimulated the lysosomal enzyme activity of AM in vitro, and enhanced colony stimulating activity (CSA) was detected from this supernatant. These results demonstrate that SSG given by the oral route can activate murine AM both qualitatively and quantitatively, and it would mediated, at least in part, by the activation of PP cells in the intestine.

Oral administration of SSG, a β -glucan obtained from Sclerotinia sclerotiorum, affects the function of Peyer's patch cells

The effect of orally administered SSG, a beta-1,3-glucan obtained from the culture filtrate of a fungus, Sclerotinia sclerotiorum IFO 9395, on the function of Peyers patch (PP) cells was investigated in comparison with that on spleen cells in mice. Oral administration of SSG enhanced the proliferative response of PP cells to a T-cell mitogen, concanavalin A (Con A), and a B-cell mitogen, lipopolysaccharide (LPS), although the response of spleen cells was not affected. Peyers patch cells taken from mice which had received oral administration of SSG two days before, showed enhanced plaque-forming cell (PFC) response to sheep red blood cells (SRBC) after antigen (SRBC) stimulation for 5 days in vitro. These results suggest that oral administration of SSG can modulate the mucosal immune response.

Structural characterisation of a neutral antitumour β-d-glucan extracted with hot sodium hydroxide from cultured fruit bodies of Grifola frondosa

Abstract The structural characterisation of an antitumour β- d -glucan (grifolan-7N), obtained from the hot sodium hydroxide extract of Grifola frandosa , is described. Grifolan-7N, purified by digestion with alpha-amylase, precipitation with ethanol, and chromatography on Con A-Sepharose, gave a single and symmetrical peak on gel filtration with Sepharose CL-4B (0.2 m NaOH/8 m urea) and had a molecular weight of ∼1,200,000. The results of methylation analysis, 13 C-n.m.r. spectroscopy, Smith degradation, and enzymic digestion indicated grifolan-7N to be a (1→3)-linked β- d -glucan having a single β- d -glucopyranosyl group attached to position 6 of almost every third backbone unit. Grifolan-7N showed potent activity against the solid Sarcoma 180 in mice.

Voltammetric responsive sensors for organic compounds based on organized self-assembled lipoyl-β-cyclodextrin derivative monolayer on a gold electrode

Abstract Voltammetric responsive sensors based on organized self-assembled β-cyclodextrin derivative monolayers on a gold electrode (β-CD-SME) for electroinactive organic species were studied. Both theoretical considerations and experimental results proved that the reduction in the oxidation peak current of the electroactive marker, ferrocene caboxylic acid, at β-CD-SME was proportional to the concentration of the target molecule and the formation constant of the inclusion complexes with β-CD. The application of the sensor as a detector for ursodeoxycholic and dehydrocholic acids after capillary electrophoresis (CE) separation has been tested. This sensor provides an alternative approach for the detection of electroinactive organic species, and is expected to find application in liquid chromatography (LC) and CE detection.

An Unmediated Hydrogen Peroxide Sensor Based on a Hemoglobin-sds Film Modified Electrode

ABSTRACT An unmediated hydrogen peroxide sensor is designed in this paper by employing a hemoglobin-SDS film modified electrode. Hemoglobin exhibits direct (unmediated) electrochemistry at the modified electrode. The protein also shows elegant catalytic activity towards the electrochemical reduction of hydrogen peroxide. Consequently, a prototype hydrogen peroxide sensor is prepared. Under optimum conditions, this sensor provides a linear response over the hydrogen peroxide concentrations in the range of 1×10-5∼1×10-4 mol/L. The detection limit was 2×10-6 mol/L The relative standard deviation was 4.2% for 6 successive determinations of the hydrogen peroxide at 1×10-5 mol/L. This configuration is shown to be sensitive, stable and easily fabricated. It might be useful in the biological and industrial fields.

Construction of positively-charged layered assemblies assisted by cyclodextrin complexation

A beta-cyclodextrin dimer is found to be effective in preparing a layer-by-layer architecture of positively charged ferrocene-appended poly(allylamine) presumably on the basis of strong beta-cyclodextrin-ferrocene host-guest interaction.

Dansyl-Modified γ-Cyclodextrin as a fluorescent sensor for molecular recognition

Dansyl-Modified γ-Cyclodextrin (1) has been prepared as a sensor for detecting organic compounds.1 shows pure monomer fluorescence whose intensity is decreased or enhanced upon addition of guest species. The value ΔI/I0, whereI andI0 are fluorescence intensities in the presence and absence of a guest and ΔI isI0−I, was used as a parameter of sensitivity.1 exhibits highly sensitive and selective molecular recognition ability, particularly, for ursodeoxycholic acid, chenodeoxycholic acid, and lithocholic acid.

Induction of oral tolerance after feeding of ragweed pollen extract in mice.

The induction of oral tolerance following the feeding of ragweed pollen and its extract was investigated in BALB/c mice. Antibody class-specific immune suppression could be observed, and the IgE response was specifically suppressed, depending on the amount of ragweed pollen extract fed when subsequently immunized with ragweed extract together with A1(OH)3 as an adjuvant. A multiple feeding was more effective than a single feeding of antigen, and the IgE response was completely suppressed when 20 mg of pollen extract was fed for 5 consecutive days. On the other hand, IgG production was not suppressed even though a large amount of ragweed pollen or its extract was fed. Furthermore, no secretion of antigen-specific IgA into saliva was observed in control animals or those fed ragweed pollen extract. Thus, pollen extract feeding may be potentially useful for the prophylaxis or therapy of allergic rhinitis induced by ragweed.

Thiazolidinediones inhibit REG Iα gene transcription in gastrointestinal cancer cells

REG (Regenerating gene) Ialpha protein functions as a growth factor for gastrointestinal cancer cells, and its mRNA expression is strongly associated with a poor prognosis in gastrointestinal cancer patients. We here demonstrated that PPARgamma-agonist thiazolidinediones (TZDs) inhibited cell proliferation and REG Ialpha protein/mRNA expression in gastrointestinal cancer cells. TZDs inhibited the REG Ialpha gene promoter activity, via its cis-acting element which lacked PPAR response element and could not bind to PPARgamma, in PPARgamma-expressing gastrointestinal cancer cells. The inhibition was reversed by co-treatment with a specific PPARgamma-antagonist GW9662. Although TZDs did not inhibit the REG Ialpha gene promoter activity in PPARgamma-non-expressing cells, PPARgamma overexpression in the cells recovered their inhibitory effect. Taken together, TZDs inhibit REG Ialpha gene transcription through a PPARgamma-dependent pathway. The TZD-induced REG Ialpha mRNA reduction was abolished by cycloheximide, indicating the necessity of novel protein(s) synthesis. TZDs may therefore be a candidate for novel anti-cancer drugs for patients with gastrointestinal cancer expressing both REG Ialpha and PPARgamma.