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Summary: The deacetylation of PGC-1α by the activation of sirtuins (SIRTs) with resveratrol (Res) promotes mitochondrial function and metabolic homeostasis. However, Res may not have the ability to specifically promote the deacetylation of PGC-1α by activating SIRT1. We investigated whether the specific deacetylation of PGC-1α is enhanced by increasing the rate of the enzyme-catalyzed reaction of SIRT1 and affects mitochondrial function and metabolic homeostasis. We previously demonstrated that alkylresorcinols (ARs) raised the Vmax of recombinant SIRT1 for NAD+ and extended the Drosophila melanogaster lifespan. Herein, we observed that treatment with the short alkyl chain-length resorcinol olivetol protected mice against diet-induced obesity with SIRT1 activation for PGC-1α. These olivetol effects were superior to Res for all parameters. Olivetol effects were associated with an induction of genes for lipid metabolism and were largely explained by PGC-1α deacetylation. Olivetol specifically activated PGC-1α deacetylation, increased mitochondrial numbers, and accelerated fat burning.

We evaluated the effect of tomato saponin, containing esculeoside A, a major saponin found in Japanese pink-colored tomato, on collagen-induced arthritis DBA/1J mice. Arthritis scores in collagen-injected mice were markedly lower by tomato saponin supplementation than that of the control throughout the 15-days observation period. Notably, there was a significant negative correlation between the arthritis scores and serum concentrations of esculeogenin A, an aglycon of esculeoside A (R2 = 0.84, p

Indoleamine 2,3-dioxygenase 2 (Ido2) is a recently identified catalytic enzyme in the tryptophan-kynurenine pathway that is expressed primarily in monocytes and dendritic cells. To elucidate the biological role of Ido2 in immune function, we introduced lipopolysaccharide (LPS) endotoxin shock to Ido2 knockout (Ido2 KO) mice, which led to higher mortality than that in the wild type (WT) mice. LPS-treated Ido2 KO mice had increased production of inflammatory cytokines (including interleukin-6; IL-6) in serum and signal transducer and activator of transcription 3 (stat3) phosphorylation in the spleen. Moreover, the peritoneal macrophages of LPS-treated Ido2 KO mice produced more cytokines than did the WT mice. By contrast, the overexpression of Ido2 in the murine macrophage cell line (RAW) suppressed cytokine production and decreased stat3 expression. Finally, RAW cells overexpressing Ido2 did not alter nuclear factor κB (NF-κB) or stat1 expression, but IL-6 and stat3 expression decreased relative to the control cell line. These results reveal that Ido2 modulates IL-6/stat3 signalling and is induced by LPS, providing novel options for the treatment of immune disorders.

The effects of soybean extracts were investigated in senescence-accelerated (SAMP10) mice, a mouse model of brain senescence with cognitive dysfunction. Mature soybeans are usually yellow. However, the green soybean retains green color after being ripened. Cognitive functions were significantly better-preserved in aged mice fed green soybean than age-matched control mice with or without yellow soybean feeding. Molecular mechanisms of the beneficial effect of green soybean on brain functions were examined through transcriptome analysis of SAMP10 hippocampus. The high expression of Ptgds was significantly associated with green soybean diet, which encodes lipocalin-type prostaglandin D2 synthase, a putative endogenous amyloid β(Αβ)-chaperone. In consonance, Aplp1 expression was significantly reduced, a member of amyloid precursor proteins. Furthermore, the amount of Aβ 40 and 42 was reduced in the insoluble fraction of cerebral cortex. These results suggest that the intake of green soybean ameliorates cognitive dysfunction of aged mice through the reduction of Aβ accumulation.

Sirtuins are enzymes that catalyze NAD+ dependent protein deacetylation. The natural polyphenolic compound resveratrol received renewed interest when recent findings implicated resveratrol as a potent SIRT1 activator capable of mimicking the effects of calorie restriction. However, resveratrol directly interacts with fluorophore-containing peptide substrates. It was demonstrated that the SIRT1 activation of resveratrol is affected by the amino acid composition of the substrate. Resveratrol did increase the enzyme activity in cases in which hydrophobic amino acids are at the +1 position to the acetylated lysine in the substrate. Alkylresorcinols (ARs) are compounds that belong to the family of phenolic lipids, and they are found in numerous biological species. Here we show that the natural activators ARs increased the Vmax of recombinant SIRT1 for NAD+ and peptide substrate, and that ARs decreased acetylated histone in human monocyte cells by stimulating SIRT1-dependent deacetylation of substrates. ARs also extended the lifespan of Drosophila melanogaster, which was shown to be dependent on functional Sir2. Our results demonstrated that ARs are natural catalytic activators for sirtuin.

The present study was performed to investigate the immune-modulating activities of extracts from green soybean (Glycine max) in a 2,4-toluene diisocyanate (TDI)-inducing guinea pig rhinitis model and a human trial study for allergic rhinitis. Hot water extracts of green soybean were chosen for animal experimentation on the basis of their ability to regulate the production of B cell-activating factor of the TNF family and a proliferation-inducing ligand in mouse spleen cells. Green soybean extracts significantly decreased the levels of ovalubumin (OVA)-specific IgE in mice and significantly suppressed the TDI-induced nasal mucosa secretion. An open-label human pilot study was performed on 16 subjects, using Japanese cedar pollinosis. The symptom scores for Japanese cedar pollinosis were better in the long-term green soybean extracts intake group than in the withdrawal short-term intake group. Green soybean extracts had great potential as an orally active immune modulator for the treatment of various allergic diseases.

Tea, a product of the leaves and buds of the Camellia sinensis (Theaceae) plant, is one of the world’s most popular beverages. Tea can be broadly classified according to the production method as unfermented (green tea), half-fermented (oolong tea), fully fermented (black tea), or post-fermented (pu-erh tea). Green tea is mainly consumed in Japan and China, whereas black tea is primarily consumed in Western countries, India, and other parts of the world. The global production of green tea accounts for only 20 % of the total amount of tea produced, which is approximately one fourth of that of black tea [1]. However, green tea has been the primary target for investigations on health and nutrition among the various teas as indicated by a search conducted in the PubMed database in January 2015, which showed approximately 6020, 3340, 330, and 100 publications for the keywords “green tea,” “black tea,” “oolong tea,” and “pu-erh tea,” respectively. When combined with cancer, for example, the corresponding numbers of publications were approximately 2000, 670, 40, and 10, respectively.

Ultraviolet (UV) irradiation induces significant changes to skin connective tissues as a result of the degradation of collagen, which is a major structural component of the extracellular matrix. This process may be mediated by matrix metalloproteinases (MMPs). In this study, we examined the protective effect of a polyphenolic flavone, luteolin, on the expression of two matrix metalloproteinases, MMP-1 and MMP-9, in UVA- and UVB-irradiated human dermal fibroblast cells. Luteolin is found in many medicinal plants as well as in a large number of vegetables, fruits and a variety of spices. It has a number of biological activities including anti-cancer, anti-oxidant, anti-inflammatory, antiallergic and immunomodulatory activities. Human dermal fibroblast (HDF) cells were treated with luteolin at 1-10 μM, then irradiated with UVA at 10 J/cm2 and UVB at 200 mJ/cm2. Cells and culture supernatant were harvested 24 h after irradiation. Our results show that luteolin at 1-10 μM dose-dependently suppressed the expression of MMP-1 and MMP-9 genes in UVA and UVB-exposed HDF cells, as measured by quantitative real-time reverse transcription–polymerase chain reaction (qRT-PCR). Luteolin was also found to reduce the production of MMP-1 protein in UVA and UVBexposed HDF cells detected by enzyme-linked immunosorbent assay (ELISA) in a dose-dependent manner. The release of MMP-9 was also reduced by luteolin in UVB-irradiated HDF cells in a dose-dependent manner. Our results indicate that luteolin can inhibit UV-induced MMP-1 and MMP-9 expression in HDF cells. Therefore, they may be potentially useful in the prevention and treatment of skin photoaging.

A PCR-based method was developed to distinguish between durum/common wheat and common wheat by leveraging slight differences of DNA sequence in Starch Synthase II (SS II) coded on wheat A, B and D genomes. A primer pair, SS II ex7-U/L, was designed to hybridize with a conserved DNA sequence region found in SS II-A, B and D genes. Another primer pair, SS II-D 1769U/1889L, was constructed to recognize a unique sequence in the SS II-D gene. The target region of SS II ex7-U/L with the size of 114 bp was amplified from durum and common wheat DNA, while no amplification was observed from any cereals other than those in the wheat genus. A DNA fragment with the size of 121 bp was specifically amplified from common wheat with SS II-D 1769U/1889L. In blended flour prepared from wheat and other cereals, the developed PCR system composed of two primer pairs effectively detected durum/common wheat and common wheat. These results suggested that PCR using two primer pairs is useful for detecting common and/or durum wheat in blended flour and could be utilized to ensure accurate food labeling.

Many biological activities of green tea have been attributed to a major constituent, (minus;)-epigallocatechin gallate (EGCG). We previously reported that EGCG and an EGCG-free fraction derived from green tea modulated the gene expression of gluconeogenic enzymes, glucose-6-phosphatase and phosphoenolpyruvate carboxykinase, in the mouse liver. EGCG is also known to affect the gene expression of enzymes related to lipid metabolism. However, it remains to be examined whether or not a constituent other than EGCG contributes to the change in gene expression of these enzymes. In this study, we prepared an EGCG-free water-soluble fraction (GT-W), and examined its effects on the hepatic gene expression of lipogenic enzymes in mice. The results of quantitative real-time PCR assays indicated that the dietary administration of GT-W for 4 weeks reduced the hepatic gene expression of lipogenic enzymes: fatty acid synthase, hydroxymethylglutaryl coenzyme A reductase, and acetyl-coenzyme A carboxylase alpha. Also, the gene expression of sterol regulatory element-binding transcription factor (Srebf)1 and/or Srebf2 was reduced, suggesting that the reduction of Srebfs contributed to the down-regulation of the lipogenic enzymes, since these transcription factors bind the promoter region to enhance their expression. The plasma levels of triglycerides and cholesterol were reduced with statistical significance in the group given a diet containing GT-W. These results suggest that in addition to EGCG, green tea contains some component(s) which may help to prevent arteriosclerosis and obesity.

Many biological activities of green tea have been attributed to a major constituent, (-)-epigallocatechin gallate (EGCG). We previously reported that EGCG and a catechin-rich green tea beverage modulated the gene expression of gluconeogenic enzymes, glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK), in the mouse liver. However, it remains to be examined whether or not a constituent other than EGCG contributes to the change in gene expression of these enzymes. In this study, we separated the hot water infusion of green tea leaves (GT) into an ethanol-soluble fraction (GT-E) and an EGCG-free water-soluble fraction (GT-W), and examined their effects using rat hepatoma H4IIE cells. The inclusion of GT, GT-E, and GT-W in the culture medium reduced the gene expression of G6Pase and PEPCK. GT-W caused a decrease in expression of the transcription factor HNF4α. Reduced levels of PEPCK and HNF4α proteins were demonstrated in the cells treated with GT-W. GT-W showed an activity similar to insulin, but different from EGCG. Administration of GT-W to mice for 4 weeks reduced the hepatic expression of G6Pase, PEPCK, and HNF4α. These results suggest that green tea contains some component(s) with insulin-like activity distinguishable from EGCG and that drinking green tea may help to prevent diabetes.

Immunoglobulin E (IgE) plays an important role in allergic diseases. In this study, we found that am ethanol extract of leaves of the camphor tree Cinnamomum camphora (C. camphora )r educed the amount of IgE secreted by human myeloma U266 cells. When the methanol extract was fractionated by extraction with organic solvents, the ethyl acetate fraction showed the highest activity. The fraction was further separated into several subfractions by preparative TLC. We identified the component of one of the active subfractions as dimethylmatairesinol. Authentic dimethylmatairesinol exhibited similar activity. Thus, the extract of C. camphora and its components including dimethylmatairesinol have potential as an anti-allergic agent.

Green-mature soybean ( Glycine max) extract (GSE) inhibits the progression of immunoglobulin E-mediated inflammation more than the ordinary yellow-pigmented soybean extract (YSE). The inhibition of nitric oxide (NO) production by GSE in lipopolysaccharide-stimulated RAW264.7 cells has been found to be lower than that by YSE. However, this inhibitory ability became markedly pronounced by visible light irradiation. We investigated the anti-inflammatory effects of GSE and visible light-irradiated GSE (L-GSE) on dextran sodium sulfate (DSS)-induced colitis, immunoglobulin E-independent inflammation, and assessed whether light irradiation affects their anti-inflammatory properties. The severity of DSS-induced colitis was moderated by the ingestion of any of the soybean extracts, and L-GSE was the most effective in moderating the progression in colitis. GSE and L-GSE, except for YSE, inhibited the mRNA expressions of pro-inflammatory cytokines and chemokine in mice colons. All soybean extracts suppressed the mRNA expression of inducible nitric oxide synthase (iNOS), whereas GSE and L-GSE also inhibited the expression of the iNOS protein in the early phase of colitis. These results suggest that GSE is likely to suppress NO production, unlike in vitro results. Unfortunately, a significant difference in the anti-inflammation ability of GSE and L-GSE was not observed in the DSS-induced colitis mice. However, GSE and L-GSE are likely to become new candidate agents for the inhibition of inflammation and excessive NO production.

Inflammation is an immune response against both internal and external antigens in organisms, particularly in mammals, and includes both uncontrolled chronic and low-grade inflammations. Uncontrolled chronic inflammation often leads to severe diseases such as vascular disease, arthritis, cancer, diabete, allergy, and autoimmunity. On the other hand, low-grade inflammation is recognized as a relationship between obesity and risk of metabolic syndrome. Elevated production of pro-inflammatory cytokines and mediators is commonly observed in patients with uncontrolled or low-grade inflammation-associated diseases. Plants have been generated phytochemicals to overcome inflammations and infections through evolution. Phytochemicals belong to alkaloids, polyphenols, flavonoids, coumarins, and terpenoids. The consumption of soybeans plays a role in immune modulation through their components such as isoflavones, saponins, and anthocyanins. Recently, it was reported that the application of phytochemicals into patients with inflammatory diseases improves their symptoms. Therefore, it is important to identify novel phytochemicals with immunomodulatory activities. This review introduces and discusses recent advances and patents regarding soybean or processed soy food compounds which exhibit immunomodulatory activity in immune diseases, particularly allergy, by mediating the suppression of inflammatory pathways.

To elucidate the bioavailability of luteolin and its glycosides in Chrysanthemum morifolium flowers, the absorption and metabolism of luteolin from them was investigated in rats and Caco-2 cells using HPLC and LC-MS. After oral administration of C. morifolium extract (1.7 g/kg body weight (bw), equivalent to 22.8 and 58.3 μmol/kg bw of luteolin and luteolin-7-O-glucoside, respectively) to rats, luteolin and its glycosides were quickly absorbed and luteolin, luteolin monoglucoside, and luteolin monoglucuronide were detected in the plasma. Their levels were highest at 1 h after administration (0.76 ± 0.27 μM). These compounds were also detected in media on the basolateral side from Caco-2 cells treated with the C. morifolium extract. These results suggest that luteolin and luteolin monoglucoside are rapidly absorbed after administration of C. morifolium flower extract and that luteolin, luteolin monoglucoside, and luteolin monoglucuronide may circulate in humans.

Parasite molecules offer unique advantages for the treatment of immunologicical disorders, and several candidate molecules have been shown to be effective. In our studies, it was shown that a factor inducing immunoglobulin E from filarial nematode parasites was suppressive in animal models of immunological disorders such as allergy and insulin dependent diabetes mellitus (IDDM). The Th1/Th2 paradigm of CD4+ T helper cell subsets can provide the basis for the development of new types of drugs and of novel strategies for the treatment of allergic and autoimmune disorders by parasite molecules. In our experimental system, parasite molecules from a filarial nematode parasite led to the down-regulation of the allergic reaction in animal models. In the majority of hosts, infection with helminths is associated with markedly reduced cellular immune reactions and polarization of T cell responses to Th2 and Th3 types. Some studies have suggested that the stimulation of host immunoregulatory networks with parasite molecules leading to the synthesis of anti-inflammatory cytokines (interleukin10, transforming growth factor-beta (TGF-beta and others) can provide new therapy for immunological disorders. It is known that parasites produce some types of molecule that mimic host molecules such as CD40 ligand, TGF-beta and macrophage migration inhibitory factor. These molecules are also candidates for medicinal agents. This review describes many of the latest possibilities in this field and shows how they can be best put to use for the development of medicinal agents, molecular target identification, and for prioritization.

The mucosal immune system provides the first line of defense against inhaled and ingested pathogenic microbacteria and viruses. This defense system, to a large extent, is mediated by the actions of secretory IgA. In this study, we screened 140 strains of lactic acid bacteria for induction of IgA production by murine Peyer's patch cells. We selected one strain and named it Lactobacillus plantarum AYA. We found that L. plantarum AYA-induced production of IL-6 in Peyer's patch dendritic cells, with this production promoting IgA(+) B cells to differentiate into IgA-secreting plasma cells. We also observed that oral administration of L. plantarum AYA in mice caused an increase in IgA production in the small intestine and lung. This production of IgA correlated strongly with protective ability, with the treated mice surviving longer than the control mice after lethal influenza virus infection. Our data therefore reveals a novel immunoregulatory role of the L. plantarum AYA strain which enhances mucosal IgA production and provides protection against respiratory influenza virus infection.

Immune responses to parasitic helminth are usually characterized by quite mysterious phenomena: dominance of Th2-like immunity and antigen-nonspecific IgE secretion. We previously purified a factor from Dirofilaria immitis that induces antigen-nonspecific IgE in rats and named it DiAg. In the presence of IL-4, DiAg induces mouse B cells to secrete IgE, which is antigen-nonspecific polyclonal antibody. We investigated the biochemical characteristics of DiAg as a factor of inducing IgE in this study. Recombinant DiAg (rDiAg) with interleukin (IL)-4 induced IgE synthesis in highly purified human normal B cells in vitro cell culture systems. The addition of recombinant human soluble CD40 IgG fusion protein (rsCD40-Ig) inhibited induction of IgE synthesis by rDiAg with IL-4. Monocyte cells were stimulated with rDiAg and recombinant human soluble CD40L (rsCD40L); IL-12 and TNF-alpha were induced. The addition of rsCD40-Ig to THP-1 cells activated with rDiAg and rsCD40L inhibited the production of IL-12. rDiAg bound to the monocyte cell membrane fraction and recombinant human soluble CD40; this binding of rDiAg was competitively inhibited by addition of rsCD40L. Moreover, in CD40-deficient mice, IgE production and MLN-B cell proliferation by rDiAg were completely absent. Based on these results, we concluded that DiAg is an agonist of CD40.

Parasitic helminth infections are characterized by eosinophilia and markedly elevated levels of circulating antigen-nonspecific immunoglobulin E (IgE), responses from which concern helminth protection. We previously purified a factor from Dirofilaria immitis that induces antigen-nonspecific IgE in mice and rats. Recombinant DiAg (rDiAg) has various biological activities. It is also known that parasitic helminth infection generates tremendous Th2 responses. The nonobese diabetic (NOD) mouse spontaneously develops Th1 cell-dependent autoimmune diabetes. Here we investigated the effects of rDiAg on the initiation and progression of this disease. rDiAg treatment of 6-week-old NOD females (the age at which insulitis typically begins) completely prevented insulitis and diabetes. Thus, rDiAg impaired the islet Ag-specific Th1 cell response in vivo, and the prevention of diabetes by rDiAg was associated with switching of the response from a Th1 to a Th2 profile. Since rDiAg clearly prevented insulitis by inhibiting the development and further accumulation of pathogenic Th1 cells to islets of Langerhans, we conclude that DiAg is a native Th2 inducer in filarial helminth and that Th1 responses are required for early events in the development of spontaneous autoimmune diabetes. In conclusion, the presence of parasitic helminth infections may play an important role as an immunomodulator in some autoimmune diseases or allergies.

Background: High levels of antigen-nonspecific IgE are produced in animals infected with helminth parasites. Generally, the increase in IgE is thought to exacerbate allergic reactions. However, high levels of antigen-nonspecific IgE may alter some features of anaphylactic reactions. To investigate the molecular mechanisms of antigen-nonspecific IgE production induced during filarial infections, we previously constructed rDiAg (recombinant Dirofilaria immitis-derived antigen) in Escherichia coli. In the present study, we examined the effect of rDiAg on the production of antigen-nonspecific IgE and on allergic cutaneous reactions in rats. Methods: Osmotic pumps filled with 200 µg of rDiAg or with 200 µl of PBS (control) were subcutaneously implanted in Wistar rats, and plasma samples were collected weekly thereafter. IgE levels were determined by ELISA. Homologous passive cutaneous anaphylaxis (PCA) reactions with anti-DNP-As IgE were examined 21 days after implantation. 125I-IgE binding assays were examined on peritoneal mast cells from rDiAg-infused rats and control rats. Results: Antigen-nonspecific IgE production was induced in rDiAg-infused rats. PCA reactions were suppressed in rDiAg-infused rats in spite of high levels of IgE and a markedly increased expression of FcΕRI. 125I-IgE did not bind to mast cells derived from rDiAg-infused rats, but it bound dose dependently to mast cells derived from control rats. Conclusion: The present data support the hypothesis that antigen-nonspecific IgE might protect against antigen-specific IgE by means of competition for mast cell receptors. rDiAg is an essential factor to induce antigen-nonspecific IgE in helminth infections.

Indoleamine 2,3-dioxygenase (IDO) 1, that catalyzes the first and rate-limiting step in the degradation of L-tryptophan, has an important immunomodulatory function. The activity of IDO1 increases in various inflammatory diseases, including tumors, autoimmune diseases, and different kinds of inflammation. We evaluated the suppressive effect of plant extracts or phytochemicals on IDO1 induction and activity; sixteen kinds of plants extracts and fourteen kinds of phytochemicals were examined. As a result, the methanol extracts of Myoga flower buds, which are traditional Japanese foods, and labdane-type diterpene galanal derived from Myoga flowers significantly suppressed IDO1 activity. The Lineweaver-Burk plot analysis indicated that galanal is a competitive inhibitor. Galanal attenuated L-kynurenine formation with an IC50 value of 7.7 µM in the assay system using recombinant human IDO1, and an IC50 value of 45 nM in the cell-based assay. Further, mechanistic analysis revealed that galanal interfered with the transcriptional function of the nuclear factor-κB and the interferon-γ signaling pathway. These effects of galanal are important for immune response. Because the inhibitory effect of galanal on IDO1 activity was stronger than that of 1-methyl tryptophan, a tryptophan analog, galanal may have great potential as the novel drug for various immune-related diseases.

We conducted a preliminary investigation of the effects of visible light irradiation on plant extracts and we observed a strong suppressive effect on interleukin (IL) 2 expression with the inhibition of c-Jun amino-terminal kinase (JNK) phosphorylation in Jurkat cells by visible light irradiation to ethanol extract from green soybeans (LIEGS). This effect was produced only by extracts from green soybeans (Glycine max) and not other-color soybeans. LIEGS suppressed the lipopolysaccharide-induced IL-6, IL-12 and TNF-α expression levels in human monocyte THP-1 cells in a concentration-dependent manner. LIEGS was applied for 8 weeks to NC/Nga mice. LIEGS suppressed the development of atopic dermatitis (AD)-like skin lesions and reduced the dermatitis scores of the mice. The light irradiation changed the various types of small-molecule compounds in extracts. Visible light irradiation to daidzein with chlorophyll b induced a novel oxidative product of daidzein. This product suppressed IL-2 expression in Jurkat cells.

To develop a method for detecting GM wheat that may be marketed in the near future, we evaluated the proline-rich protein (PRP) gene as an endogenous reference gene of common wheat (Triticum aestivum L.) and durum wheat (Triticum durum L.). Real-time PCR analysis showed that only DNA of wheat was amplified and no amplification product was observed for phylogenetically related cereals, indicating that the PRP detection system is specific to wheat. The intensities of the amplification products and Ct values among all wheat samples used in this study were very similar, with no nonspecific or additional amplification, indicating that the PRP detection system has high sequence stability. The limit of detection was estimated at 5 haploid genome copies. The PRP region was demonstrated to be present as a single or double copy in the common wheat haploid genome. Furthermore, the PRP detection system showed a highly linear relationship between Ct values and the amount of plasmid DNA, indicating that an appropriate calibration curve could be constructed for quantitative detection of GM wheat. All these results indicate that the PRP gene is a suitable endogenous reference gene for PCR-based detection of GM wheat.

Green tea has been shown to have many beneficial health effects. We have previously reported that dietary (-)-epigallocatechin-3-O-gallate (EGCG), the major polyphenol in green tea, reduced gene expressions of gluconeogenic enzymes, glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK), in the normal mouse liver. In the present study, we examined the effects of intragastrical administration of EGCG on the expression of gluconeogenesis-related genes in the mouse intestine. The results of experiments with the semi-quantitative reverse transcription-polymerase chain reaction indicated that EGCG at 0.6 mg/head caused a reduced expression of G6Pase, PEPCK, hepatocyte nuclear factor 1α (HNF1α), and HNF4α. Experiments using the quantitative real-time polymerase chain reaction confirmed these effects. We then examined the effects of EGCG using human colon carcinoma Caco-2 cells stimulated with dexamethasone and dibutyryl cAMP. The results were generally consistent with those from the experiments in vivo. The present findings suggest EGCG to contribute to the beneficial effects of green tea on diabetes, obesity, and cancer by modulating gene expression in the intestine.

Tea has many beneficial effects. We have previously reported that green tea and a catechin-rich green tea beverage modulated the gene expression of the gluconeogenic enzymes glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK) in the normal murine liver. In the present study, we examined the effects of oral administration of oolong tea on the hepatic expression of gluconeogenesis-related genes in the mouse. The intake of oolong tea for 4 weeks reduced the hepatic expression of G6Pase and PEPCK together with that of the transcription factor hepatocyte nuclear factor (HNF) 4α. When rat hepatoma H4IIE cells were incubated in the presence of oolong tea, the expression of these genes was repressed in accordance with the findings in vivo. The reduced protein expression of PEPCK and HNF4α was also demonstrated. We then fractionated oolong tea by sequential extraction with three organic solvents to give three fractions and the residual fraction (Fraction IV). In addition to organic fractions, Fraction IV, which was devoid of low-molecular-weight catechins such as (-)-epigallocatechin gallate (EGCG), had effects similar to those of oolong tea on H4IIE cells. Fraction IV repressed the gene expression of insulin-like growth factor binding protein 1, as insulin did. This activity was different from that of EGCG. The present findings suggest that drinking oolong tea may help to prevent diabetes and that oolong tea contains a component or components with insulin-like activity distinguishable from EGCG. Identification of such component(s) may open the way to developing a new drug for diabetes.

The mammalian fetuses are semi-allograft for mothers. Therefore the failure of immunological tolerance often causes pregnancy loss. Recently, the effects of helminthes therapy for immune mediated diseases have been reported. In the present study we employed the murine model to examine the therapeutic potential of the recombinant antigen from a nematoda parasite, Dirofilaria immitis for immune mediated pregnancy loss. Recombinant D. immitis polyproteins (rDiAg) had been cloned and selected by us for the strongest immuno-regulatory activities in parasite antigens. Female CBA/J mice were injected with sterilized rDiAg or PBS solution using micro-osmotic pumps before mating. Pregnant CBA/J mice were sacrificed on day 13.5 for scoring the number of resorbed and viable fetuses for histological and immunological analysis. The serum cytokine concentrations were measured using suspension array system. The resorption rate of mock-treated mice was 42.9% (resorbed fetus 12/total fetus 28). The resorption rate was decreased to 11.1% (resorbed fetus 3/total fetus 27) with rDiAg treatments. The IL-4, IL-23 and TNF-α concentrations in serum were significantly lower in rDiAg-treated mice than mock-treated mice. The serum IL-17 level was also reduced in rDiAg-treated mice but the difference was not significant. The rDiAg treatment reduced the resorption rates of CBA/J×DBA/2J mouse model, which mimic human pregnancy failures with allo-immune backgrounds. Our observations suggest as the first time of therapeutic potentials of the rDiAg for pregnancy loss.

BACKGROUND: Lectins are proteins that bind specifically to the carbohydrate moiety of glyco-conjugates. Japanese mistletoe lectin given intragastrically affected cytokine gene expression in the mouse intestine. This study examines the actions of Lens culinaris agglutinin (LCA) on the gene expression of gluconeogenic enzymes in the intestine. RESULTS: The results of quantitative real-time reverse transcription–polymerase chain reaction indicated that LCA caused an up-regulation of the gene expression of glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK). This change was correlated with an increase in the expression of two transcription factors, HNF1α and HNF4α. Experiments using human colonic cancer Caco-2 cells demonstrated that LCA up-regulated the gene expression of G6Pase and PEPCK whereas insulin had the opposite effect. In addition, the observed up-regulation of HNF4α gene expression in the duodenum raises the possibility that the lectin promotes the colorectal cancer. CONCLUSION: Lentil beans should be cooked well to avoid unfavourable effects of LCA. Copyright © 2011 Society of Chemical Industry

Dirofilaria immitispolyproteins (DiAgs) are found as 15-kDa monomeric and 30-kDa dimeric forms in exceretory-secretory products of the adult worm. We evaluated the ability of various types of recombinant DiAg (rDiAg; V1 and V2 as monomers and V1V2, V2V1, V1V1, and V2V2 as dimers) to influence Th1/Th2 immune responses. V1-, V1Vx- and V2-, V2Vx-driven nonspecific immunoglobulin E (IgE) production peaked at 21 and 14 days after administration, respectively. Dimer-induced IgE response was an interesting biphasic pattern with the second peaks on days 35 (V2Vx) or 42 (V1Vx). Absolute amounts of nonspecific IgE production induced with monomers were larger than those observed with dimers at the first peak. The magnitude of cell expansion and interleukin-10 (IL-10) production in mesenteric lymph node (MLN) B-cell induced with rDiAgs was linked to the levels of the first IgE peak in vivo and IgE produced by rDiAg plus IL-4-stimulated B cells in vitro. All rDiAgs failed to augment IgG2c production. V2 and V2Vx elicited IL-4 production by MLN cells more rapidly than V1 and V1Vx. The inhibitory effect of rDiAg on gamma interferon (IFN-γ) production was stronger in monomers than in dimers. Neutralization of IL-10 restored IFN-γ production, whereas the expression of IL-4 and IgE was partly prevented by depletion of IL-10. These results indicate that monomer rather than dimer is an efficient form of DiAg and suggest that the difference of IgE-inducing capacity among these DiAgs is closely associated with the pattern of both B-cell activation and IL-4 production.

We have previously reported that in peripheral blood mononuclear cells (PBMC), the augmented expression of the beta isoform of the human glucocorticoid receptor (hGRbeta), as a putative dominant negative regulator of glucocorticoid action, is associated with glucocorticoid (GC) unresponsiveness of UC patients. In this study, we quantified the levels and serial changes of hGR transcripts in PBMC of IBD patients by a real-time fluorescence monitoring of PCR. As results, relative hGRbeta mRNA expression was significantly higher in the active stage of UC than in inactive periods of UC or CD patients. Longitudinal analysis revealed that hGRbeta mRNA expression in UC was increased after the relapse of inflammation, suggesting that the overproduction of cytokines during inflammation may be responsible. In in vitro culture experiments of human lymphoid cell (CEM) and human PBMC, IL-7, and IL-18 increased hGRbeta mRNA expression in these cells but GC itself did not. Through these analyses, it is indicated that the inflammatory cytokines altered the splicing condition of the primary transcript of hGR gene in IBD patients.

We investigated the effect of recombinantDirofilaria immitispolyprotein (rDiAg) on nitric oxide (NO) production by peritoneal macrophages. rDiAg induced NO production by macrophages from wild-type and lipopolysaccharide-hyporesponsive C3H/HeJ, but not CD40−/−, mice. These results suggest that CD40 is involved in rDiAg-driven NO production by murine macrophages.

Nonspecific immunoglobulin E (IgE) production is an event characteristically observed in parasitic helminth infections, but its mechanisms are still unclear. To define these mechanisms, we prepared a recombinantDirofilaria immitisprotein (rDiAg) and assessed its effect on nonspecific IgE production. rDiAg preferentially induced nonspecific IgE production, without eliciting specific IgE production, as well as a Th2-type cytokine profile (high interleukin-4 [IL-4] and IL-10 production but low gamma interferon production) in BALB/c mice. rDiAg significantly elicited the proliferative response of naive B cells. This response was not abolished by polymyxin B, an inhibitor of lipopolysaccharide (LPS), and rDiAg normally expanded splenic B cells from LPS nonresponder C3H/HeJ mice. Thus, the mitogenic effect of rDiAg was not due to LPS contamination. rDiAg also enhanced levels of CD23 expression on splenic B cells. Splenic B cells produced marked levels of IgE when cultured with the combination of rDiAg and IL-4 (rDiAg-IL-4), whereas peritoneal B cells produced negligible levels of IgE. rDiAg-IL-4-induced IgE production by splenic B cells was synergistically increased by coculture with peritoneal B cells. rDiAg-driven IL-10 secretion was higher in peritoneal B cells than in splenic B cells. IgE production by splenic B cells cocultured with peritoneal B cells was decreased to a level comparable to that by splenic B cells in the presence of a neutralizing anti-IL-10 monoclonal antibody. Collectively, these results suggest that rDiAg-induced polyclonal expansion and IgE class switching of splenic B cells contribute to nonspecific IgE production and that these responses are enhanced by peritoneal B-cell-derived IL-10.

Background & Aims: Recently, the glucocorticoid receptor β (hGRβ) was suggested to play a role as a dominant negative regulator for determining glucocorticoid response. The aim of this study was to clarify whether reverse-transcription polymerase chain reaction (RT-PCR) analysis of hGRβ messenger RNA (mRNA) can predict the response to glucocorticoids in patients with ulcerative colitis. Methods: Total RNA obtained from peripheral blood mononuclear cells (PBMCs) of 23 patients with ulcerative colitis and 20 healthy volunteers was reverse transcribed; the resulting complementary DNA was amplified using specific primers for hGRα and hGRβ. Protein expression of hGR in PBMCs was confirmed by immunoprecipitation–Western blot analysis. Results: The expression of hGRα mRNA (477 base pairs) was detected in all patients and all healthy volunteers. In contrast, a hGRβ mRNA (366 base pairs) was detected in 1 (9.1%) of 11 glucocorticoid-sensitive patients, 10 (83.3%) of 12 glucocorticoid-resistant patients, and 2 (10%) of 20 healthy volunteers. The positive rate of hGRβ mRNA in the resistant group was significantly higher than that in the sensitive group ( P = 0.0019). The hGRβ band could be detected by immunoprecipitation–Western blotting in hGRβ mRNA–positive patients. Conclusions: The results show that the expression of hGRβ mRNA in PBMCs examined by RT-PCR may serve as a novel predictor of glucocorticoid response in ulcerative colitis. GASTROENTEROLOGY 2000;118:859-866