The histidine-containing protein (HPr) is the energy coupling protein of the phosphoenolpyruvate-dependent carbohydrate:phosphotransferase system (PTS), which catalyzes the transport of carbohydrates in bacteria. In Bacillus subtilis and close relatives, global regulation of carbon catabolite control occurs on the binding of the complex of CcpA (catabolite control protein A) and P-Ser-HPr (seryl-phosphorylated form of HPr) to the catabolite responsive elements (cre) of the target operons, the constituent genes of which are roughly estimated to number 300. The complex of CcpA and P-Ser-HPr triggers the expression of several genes involved in the formation of acetate and acetoin, major extracellular products of B. subtilis grown on glucose. It also triggers the expression of an anabolic operon (ilv-leu) involved in the biosynthesis of branched-chain amino acids, which subsequently leads to cell propagation. On the other hand, this complex represses many genes and operons, which include an entrance gene for the TCA cycle (citZ), several transporter genes for TCA cycle-intermediates, some respiration genes, and many catabolic and anabolic genes involved in carbon, nitrogen, and phosphate metabolism, as well as for certain extracellular enzymes and secondary metabolites. Furthermore, these bacteria have CcpA-independent catabolite regulation systems, each of which involves a transcriptional repressor of CggR or CcpN. CggR and CcpN are derepressed under glycolytic and gluconeogenic growth conditions, and enhance glycolysis and gluconeogenesis respectively. Another CcpA-independent catabolite repression system involves P-His-HPr (histidyl-phosphorylated form of HPr). P-His-HPr phosphorylates and activates glycerol kinase, whose product is necessary for antitermination of the glycerol utilization operon through GlpP, the antiterminators (LicT and SacT, Y) of several operons for the utilization of less-preferred PTS-sugars, and some transcriptional activators such as LevR for the levan utilization operon. This phosphorylation is reduced due to the decreased level of P-His-HPr during active transport of a preferred PTS-carbohydrate such as glucose, resulting in catabolite repression of the target operons.
Thus CcpA-dependent and independent networks for carbon metabolism play a major role in the coordinate regulation of catabolism and anabolism to ensure optimum cell propagation in the presence and the absence of a preferred PTS-carbohydrate.

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Analysis of products digested by glycosyl hydrolases helps understanding of the hydrolysis mechanism and the substrate recognition in the enzymes. We developed a new universal technique, which consists of ruthenium (II) complex labeling and mass spectrometry analysis, to identify the reducing sugars released from oligosaccharides by enzymatic digestion. This method was applied to enzymatic digestion by chitinase and cellulase of the hyperthermophilic archaea Pyrococcus fusiosus and Pyrococcus horikoshii respectively.

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Dechlorodauricumine (5) and dechloroacutumine (6) were converted to miharumine (7) and dechloroacutumidine (8), respectively, by a cell-free preparation from cultured roots of Menispermum dauricum in the presence of FAD. The structures of 7 and 8 were elucidated on the basis of spectroscopic analyses and chemical conversion.

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This study was designed to determine the morphological and biochemical effects of zinc sulfate and the role of metallothionein in ethanol-induced intestinal injury. Rats received zinc sulfate (100 mg/kg/d) for 3 consecutive d, 2 h prior to the administration of ethanol by gavage. Ethanol administration caused intestinal injury as determined by increased serum lactate dehydrogenase activity, urea, creatinine, uric acid, and sialic acid levels, intestinal lipid peroxidation level, decreased serum catalase activity, intestinal glutathione level, and metallothionein expression. Zinc sulfate pretreatment of the ethanol group caused a decrease in histological damage, serum lactate dehydrogenase activity, urea, creatinine, uric acid, sialic acid levels, and intestinal lipid peroxidation level, but increases in serum catalase activity, intestinal glutathione level, and metallothionein expression. The present study indicates that zinc sulfate has a protective effect against ethanol-induced intestinal injury. In addition, the protective effect of zinc on ethanol-induced intestinal injury might be mediated by metallothionein, as well as having antioxidative potential.

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A thermophilic pectate lyase, Pel SWU, was isolated from a culture filtrate of Bacillus sp. RN1 isolated from a hot spring in Ranong Province, Thailand. The enzyme was purified to homogeneity using cation-exchange and hydrophobic column chromatographies. The molecular mass of Pel SWU was estimated to be 33 kDa. The specific substrate was demethylated galacturonic acid. The enzyme was stable at pH 4.0–10.0 and at temperatures up to 70 °C in the presence of calcium and polygalacturonic acid (PGA). The optimum pH and temperature were 10.0 and 90 °C. The pel gene encoding Pel SWU was 1,023 bp, which corresponds to 341 amino acids. The properties of the recombinant enzyme was similar to those of Bacillus Pel SWU. Unsaturated di- and trigalacturonic acids were formed mainly as the final products of degradation by Pel SWU, as revealed by high-performance anion-exchange chromatography (HPAEC) and electrospray ionization mass spectrometry (ESI-MS) analyses. This thermophilic pectate lyase should be useful in the degradation of pectin networks at high temperature.

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An antihypertensive peptide, Lys-Val-Leu-Pro-Val-Pro (KVLPVP), can reduce blood pressure in hypertensive rats after being orally administered. In this study, the transepithelial transport of intact KVLPVP was examined by Caco-2 monolayers. The results were as follows: (i) The flux was not saturable for apical (AP) to basolateral (BL) or BL-AP transport when the concentration of KVLPVP was 1–8 mM. (ii) Sodium deoxycholate loosened the tight junction in the Caco-2 cells and significantly improved the transport process. (iii) Phenylarsine oxide, a transcytotic process inhibitor, had little effect on the transport process. (iv) The influx and eflux of KVLPVP remained unchanged in the presence of the ATP inhibitor sodium azide. (v) This transport was not inhibited by the peptide transporter substrates Gly-Pro or arphanine A. All these data indicate that paracellular transport diffusion was the major flux mechanism for the intact KVLPVP.

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A cryopreservation condition for D-amino acid oxidase (DAAO)-overexpressing Escherichia coli (E. coli BL21(DE3)/pET-DAAO) was established. Ten percent was the optimum concentration of glycerol as a cryoprotectant, and its diffusion into stationary phase cells was superior to that into log cells. The results also showed that rather than fast cooling, a slow cooling method was appropriate to our recombinant E. coli. In addition, 15 min was the best equilibration period, at which higher than 90% of recovery rates were maintained at all test points. Most importantly, the relative recovery rates, product yield, and fermentation pattern of the cell banks (CBs) constructed according to our cryopreservation method did not change over 12 months, confirming that our method not only permits exceptional cryopreservation, but offers prolonged productivity. Taken together, our results demonstrating a cryopreservation method for E. coli BL21(DE3)/pET-DAAO provide insight into an improvement in the industrial production of DAAO.

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To identify key genes in the regulation of salt tolerance in the mangrove plant Bruguiera gymnorhiza, transcriptome profiling in the lateral and main roots under conditions of salt stress was performed. Statistical analysis revealed that 175 and 403 of 11,997 genes shoewd significantly increased high expression in the lateral and main roots respectively. One hundred and sixty genes were up-regulated in both types of roots in the early time period, 1 to 12 h after salt treatment. Expression vectors for 28 selected salt responsive genes were constructed and transformed in Agrobacterium tumefaciens, and then screened for salt tolerance. A. tumefaciens transformed with genes for lipid transfer, zinc finger, and ankyrin repeat proteins showed enhanced salt tolerance. Transgenic Arabidopsis plants expressing these three genes also exhibited increased tolerance to NaCl. These results indicate that Agrobacterium functional screening is an effective supplemental method of pre-screening genes involved in abiotic stress tolerance.

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Mild oxidative stress is known to induce premature senescence, termed stress-induced premature senescence (SIPS), in normal human diploid cells. We investigated to determine whether mild oxidative stress would trigger SIPS in a human tumor cell line, human lung adenocarcinoma A549. The results showed that sublethal concentrations of H₂O₂ induced SIPS in A549 cells and consequently attenuated, but did not completely eliminate, the tumorigenicity of these cells. We next investigated the reasons for this incomplete impairment of tumorigenicity in A549 cells in SIPS. The results suggested that H₂O₂-treated A549 cells are composed of a heterogeneous cell population: one is sensitive to H₂O₂, and the other is resistant or undergoes reversal; the latter reverted to their original tumorigenic form. The molecular mechanisms determining the cellular fate of tumor cells in SIPS should be identified in order to make use of SIPS and oncogene-induced senescence in tumor cells as methods of tumor suppression.

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Syntaxin is a component of t-soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE), which is responsible for docking membrane vesicles at the target membrane and is highly conserved among eukaryotes. In the fission yeast Schizosaccharomyces pombe, the psy1⁺ gene encoding a syntaxin 1 homolog was originally isolated as a multicopy suppressor of the sporulation-deficient mutant, spo3, but little is known about the way Psy1 is involved in sporulation. Here we report the isolation of a sporulation-defective mutant, psy1-S1, generated by random PCR mutagenesis. psy1-S1 also exhibited temperature sensitivity in growth. In psy1-S1 cells, assembly of the forespore membrane (FSM) initiated near the spindle pole bodies during meiosis II, but subsequent expansion of the membrane was severely impaired. Overproduction of the cognate SNARE proteins, Syb1 and Sec9, suppressed both the temperature sensitivity and sporulation defects of psy1-S1. These results indicate that Psy1 plays an essential role in FSM formation coordinated by Syb1 and Sec9.

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In Escherichia coli, CitA is a membrane-associated sensor histidine kinase that phosphorylates CitB, the response regulator. It is predicated to play a key role in anaerobic citrate catabolism. The citrate-binding site in CitA is located within its periplasmic domain, while the cytoplasmic domain (CitA-C) is involved in autophosphorylation. We found that autophosphorylation in vitro of CitA-C was induced by DTT. Using the whole set of CitA-C derivatives containing Cys-Ala substitution(s), Cys at 529 was found to be essential to the redox-sensing of autophosphorylation. The phosphorylated CitA-C transferred a phosphate to CitB. DNase-I footprinting assay indicated that CitB specifically bound on the intergenic region between the citA and citC genes. These results characterize the molecular mechanism of the CitA-CitB signal transduction system in E. coli.

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The stability of the oxidized and reduced forms of three homologous cytochromes c from two thermophiles and one mesophile was systematically monitored by means of Soret absorption measurements in the presence of various concentrations of a denaturant, guanidine thiocyanate, at pH 7.0 at 25 °C. Thermophilic Hydrogenobacter thermophilus cytochrome c₅₅₂ was the most stable in both redox states, followed by moderately thermophilic Hydrogenophilus thermoluteolus cytochrome c₅₅₂, and then mesophilic Pseudomonas aeruginosa cytochrome c₅₅₁. Further stability and electrochemical analysis of the three proteins and the reciprocal variants, which exhibited a different hydrophobic interaction with the heme, showed that the one with the higher stability in both redox states had the lower redox potential. Consequently, these cytochromes c probably adapted to the cellular environments of the original bacteria with correlated stability and redox potential constraints, which are in part regulated by the hydrophobicity around the heme.

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The gut mucosal immune system is crucial in host defense against infection by pathogenic microbacteria and viruses via the production of IgA. Previous studies have shown that intestinal commensal bacteria enhance mucosal IgA production. However, it is poorly understood how these bacteria induce IgA production and which genera of intestinal commensal bacteria induce IgA production effectively. In this study, we compared the immunomodulatory effects of Bacteroides and Lactobacillus on IgA production by Peyer’s patches lymphocytes. IgA production by Peyer’s patches lymphocytes co-cultured with Bacteroides was higher than with Lactobacillus. In addition, the expression of activation-induced cytidine deaminase increased in co-culture with Bacteroides but not with Lactobacillus. We found that intestinal commensal bacteria elicited IgA production. In particular, Bacteroides induced the differentiation of Peyer’s patches B cell into IgA⁺ B cells by increasing activation-induced cytidine deaminase expression.

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In eukaryotes, the hypoacetylated state of histone N-terminal lysines at many gene-promoters, which is created by histone deacetylases (HDACs), is changed to the hyperacetylated state by the function of histone acetyltransferases (HATs) upon transcription activation. Although much insight has been obtained to date as to how modification of the histone tail regulates gene expression, little is known about how the transition between the unmodified and modified states takes place. In Saccharomyces cerevisiae, the HDAC complex containing Rpd3 (Rpd3L) represses the transcription of several sets of genes through the URS1 cis-element. We found that the histone H3 acetylation level at the URS1 of seven genes (INO1, CAT2, ACS1, YAT1, RIM4, CRC1, and SIP4) was elevated in the presence of Rpd3/HDAC in growth in acetate-containing medium (YPA), suggesting that a mechanism that regulates HDAC activity is present in this organism. The biological significance of this phenomenon is discussed below.

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AmyR is a Zn(II)₂Cys₆ transcriptional activator that regulates expression of the amylolytic genes in Aspergillus species. Subcellular localization studies of GFP-fused AmyR in A. nidulans revealed that the fusion protein preferentially localized to the nucleus in response to isomaltose, the physiological inducer of the amylolytic genes. The C-terminal domains of AmyR, designated MH3 (residues 419–496) and MH4 (residues 516–542), were essential for sensing the inducing stimulus and regulating the subcellular localization. The MH2 domain (residues 234–375) located in the middle of AmyR was required for transcriptional activation of the target genes, and the nuclear localization signals were identified within the N-terminal Zn(II)₂Cys₆ DNA binding motif.

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Unlike the budding yeast Saccharomyces cerevisiae, the fission yeast Schizosaccharomyces pombe synthesizes large outer chains on the N-linked oligosaccharides that consist mainly of D-Gal and D-Man residues. The fission yeast och1⁺ gene product has α1,6-mannosyltransferase activity, and Och1p is the key enzyme in the initiation of outer chain elongation. Although the in vitro substrate specificity of S. pombe Och1p has been reported (Yoko-o et al., FEBS Lett., 489, 75–80 (2001)), the structure of the N-linked oligosaccharides of och1Δ cells has not been investigated. In this study, we report a structural analysis of S. pombe N-linked oligosaccharides. Lectin blot analysis indicated that galactose residues were attached to the cell surface glycoproteins of the och1Δ cells. We conducted a structural analysis of pyridylaminated N-linked oligosaccharides prepared from galactomannoproteins by HPLC and ¹H NMR. These analyses revealed that the N-linked oligosaccharides of the och1Δ cells displayed heterogeneity in the glycan consisting of Hex_11–15GlcNAc₂. The structural heterogeneity arose mainly from the addition of α1,2- and α1,3-Gal residues to the Man₉GlcNAc₂ core structure.

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Steroid hormones are conserved between animals and plants as signaling molecules to control growth and development. Plant steroid hormones, brassinosteroids (BRs), appear to play an important role in plant cell elongation. BRs bind to leucine-rich repeat kinase BRASSINOSTEROID-INSENSITIVE 1 (BRI1) localized to the plasma membrane, activate transcription factors in collaboration with cytosolic kinases and phosphatases, and regulate BR-responsive gene expression, but the details regarding the BR signaling pathway from perception to nuclear events remain unknown. In this study we used chemical genetics to identify an evolutionarily conserved transmembrane protein, Brz-insensitive-long hypocotyls 4 (BIL4), and demonstrated its role as a critical component of plant cell elongation occurring upon BR signaling. A dominant mutation, bil4-1D, showed cell elongation in the presence of the BR-specific inhibitor Brz. Brz suppresses expression of the BIL4 gene in wild-type plants, and overexpression of BIL4 in bil4-1D suppresses the BR deficiency caused by Brz. Our results indicate that BIL4 mediates cell elongation on BR signaling.

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The marine photosynthetic bacterium Rhodovulum sulfidophilum produces nucleic acids extracellularly. We have identified these extracellular RNAs as fully mature sized tRNAs and fragments of 16S and 23S rRNAs. Most of the tRNAs have mature 3′-terminal CCA sequences. In the present study we found that these extracellular tRNAs were not aminoacylated, although almost all intracellular tRNAs are aminoacylated.

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We identified outer membrane vesicle (OMV) production in Vibrio anguillarum O1, a major fish pathogen that causes vibriosis, and characterized the OMVs. They were produced during normal growth, and were appeared as spherical vesicle fractions. The protein profile of the OMVs was similar to that of the outer membrane proteins, and the 38-kDa major protein band of OMV was identified as OmpU. The OMVs had enzyme activity of metalloprotease, hemolysin, and phospholipase, and stimulated the production of proinflammatory cytokines, such as TNF-α, IL-1β, and IL-6 when injected into the flounder.

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Rrs1 has an essential role in 60S ribosomal subunit assembly in Saccharomyces cerevisiae. We isolated a temperature-sensitive kcs1 mutant that suppresses the cold sensitivity of rrs1-1. The kcs1 allele, resulting in truncation of inositol 6 phosphate kinase domain, and kcs1 disruption suppress a defect of rrs1-1 in 60S ribosomal subunit assembly. These results suggest that inositol polyphosphate metabolism affects ribosome biogenesis in yeast.

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Effects of an alginate oligosaccharide mixture (AOM) on Nannochloropsis oculata, a unicellular marine microalga, were investigated. The growth of N. oculata was significantly promoted by AOM in a concentration-dependent manner. The maximum effect was attained at 20 mg/ml, at which the growth rate of the alga became nearly 5 times higher than that of control without AOM. The growth-promoting effect of AOM decreased slightly at 40 mg/ml. Furthermore, the algicidal effect of Cu²⁺ was profoundly alleviated by the addition of AOM. These results suggest that AOM is useful for promoting and/or improving the growth of N. oculata.

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Matriptase is a transmembrane serine protease comprising multiple domains in the extracellular region, including a stem domain and a catalytic domain. Using soluble matriptase variants containing entire extracellular domains or only the catalytic domain, the activity of this protease was found to depend solely on the catalytic domain. The stem domain had no significant effect on the activity.

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In this study, we identified a gene encoding tomato ENGase (Endo-LE) using the gene information of rice ENGase, and expressed the Endo-LE protein in Escherichia coli. The substrate specificity of the recombinant Endo-LE was the same as that of the native enzyme, showing strong activity towards the high-mannose type N-glycans with the Manα1-2Manα1-3Manβ1-4GlcNAcβ1-4GlcNAc unit. Real-time PCR analysis revealed that the gene expression of Endo-LE did not vary significantly with the tomato ripening process, indicating that Endo-LE activity is ubiquitously expressed.

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We discovered markedly differing catabolism of nicotinamide among rat strains. We compared the catabolism of nicotinamide and also that of the other tryptophan-nicotinamide and water-soluble vitamins among the four strains, Wistar, Sprague-Dawley (SD), August-Copenhagen Irish (ACI) and Fischer 344. The major urinary catabolite of nicotinamide was N¹-methyl-4-pyridone-3-carboxamide in Wistar, SD and ACI, and N¹-methylnicotinamide in Fischer rats. This phenomenon was attributed to the enzyme activity involved in the reaction of N¹-methylnicotinamide to N¹-methyl-4-pyridone-3-carboxamide being much lower in Fischer than in the other three strains. With the water-soluble vitamins, this specific phenomenon was only observed in the catabolism of vitamin B₆; the urinary catabolite, 4-pyridoxic acid, was much lower too. It was found for the first time that the activities of oxidase were lower in Fischer than in the other strains. This study showed that Wistar, SD, ACI strains had similar water-soluble vitamin metabolism including nicotinamide catabolism.

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Electrolzyed-reduced water (ERW) is a higher pH and lower oxidation-reduction potential water. In the present study, we examined the enhanced effect of ERW in the apoptosis of leukemia cells (HL-60) induced by glutathione (GSH). An enhanced inhibitory effect on the viability of the HL-60 cells was observed after treatment with a combination of ERW with various concentrations of GSH, whereas no cytotoxic effect in normal peripheral blood mononuclear cells was observed. The results of apoptotic related protein indicated that the induction of HL-60 cell death was caused by the induction of apoptosis through upregulation of Bax and downregulation of Bcl-2. The results of further investigation showed a diminution of intracellular GSH levels in ERW, and combination with GSH groups. These results suggest that ERW is an antioxidant, and that ERW, in combination with GSH, has an enhanced apoptosis-inducing effect on HL-60 cells, which might be mediated through the mitochondria-dependent pathway.

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The effects of an orally administered combination of a glucosamine-chondroitin-quercetin glucoside (GCQG) supplement on the synovial fluid properties of patients with osteoarthritis (OA) and rheumatoid arthritis (RA) were investigated from the clinical nutrition view point. In this study, forty-six OA and twenty-two RA patients were administered with the GCQG supplement orally for 3 months. Several parameters of the knee joints were monitored before and after supplementation. The OA patients showed a significant improvement in pain symptoms, daily activities (walking and climbing up and down stairs), and visual analogue scale, and changes in the synovial fluid properties with respect to the protein concentration, molecular size of hyaluronic acid, and chondroitin 6-sulphate concentration were also observed. However, no such effects were observed in the RA patients. These results suggest that the GCQG supplement exerted a special effect on improving the synovial fluid properties in OA patients.

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Although it is well known that ultraviolet A (UVA) irradiation destroys folate, no definite conclusion for the biological degradation has yet been drawn. In the present study, we determined the effects of UVA exposure on the blood folate concentration in vitro and in vivo. UVA irradiation reduced the synthesized folate pteroylmonoglutamic acid (PGA) content in the blood, but not 5-methyltetrahydrofolate, a major folate form in the blood stream. Exposure to sunlight also decreased the plasma folate concentration in human subjects who took PGA prior to the exposure, but not in subjects who did not take PGA. These results suggest that UVA exposure destroyed PGA but not 5-methyltetrahydrofolate in human blood in vivo.

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The intestinal epithelium is a significant barrier to oral absorption of hydrophilic compounds, and their passage through the intercellular space is restricted by the tight junctions. In this study we found that hyperosmosis is a significant factor altering paracellular transport in Caco-2 cell monolayers. Osmotic regulators, such as sodium chloride, mannitol, and raffinose, decreased transepithelial electrical resistance and enhanced lucifer yellow permeability. The effect of these osmotic regulators on Caco-2 cell monolayers was not likely to be caused by gross cytotoxicity. Although certain amino acids and oligosaccharides have been reported to have specific tight junction-modulating activity, we found that the increased paracellular permeability of Caco-2 monolayers induced by these compounds was at least partly due to the increased osmotic pressure of the test solutions. These findings provide a new potential precaution in the evaluation of paracellular permeability-modulating substances using the Caco-2 cell monolayer system.

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The establishment of a simple technique to determine the concentration of fucoidan was developed by using a monoclonal antibody against fucoidan. This antibody reacted with fucoidans purified from Laminaria japonica Areschoug (Makombu in Japanese) and Kjellmaniella gyrate Miyabe (Gagome), but not with polysaccharides from Undaria pinnatifida Suringar (Wakame). Neither laminarin nor algenic acid, which are constituents in Laminaria japonica, were recognized by the prepared antibody. Application of the enzymed-linked immunosorbent assay (ELISA) inhibition assay increased the specificity of fucoidan in measuring the fucoidan contents. On the basis of these results, it was ascertained that the ELISA inhibition assay of using the anti-fucoidan monoclonal antibody was rapid, accurate, and sensitive in measuring the content of fucoidan. In addition, the localization of fucoidan in Laminaria japonica was investigated. This is the first report of fucoidan being restricted to the outer cortical layer.

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Millet is an important food crop in Asia and Africa, but the health benefits of dietary millet are little known. This study defined the effects of dietary Japanese millet on diabetic mice. Feeding of a high-fat diet containing Japanese millet protein concentrate (JMP, 20% protein) to type 2 diabetic mice for 3 weeks significantly increased plasma levels of adiponectin and high-density lipoprotein cholesterol (HDL cholesterol) and decreased the levels of glucose and triglyceride as compared to control. The starch fraction of Japanese millet had no effect on glucose or adiponectin levels, but the prolamin fraction beneficially modulated plasma glucose and insulin concentrations as well as adiponectin and tumor necrosis factor-α gene expression. Considering the physiological significance of adiponectin and HDL cholesterol levels in type 2 diabetes, insulin resistance, and cardiovascular disease, our findings imply that dietary JMP has the potential to ameliorate these diseases.

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Stroke-prone spontaneously hypertensive rats (SHRSP) deposit plant sterols in their bodies and have a mutation in ATP binding cassette transporter G5 (Abcg5). Lymphatic recovery rates of campesterol and sitosterol in SHRSP rats were comparable to those in Wistar rats, a strain that does not deposit plant sterols in the body and has no mutation in Abcg5. Higher absorption of stigmasterol and sitostanol was observed in SHRSP rats than in Wistar rats, but the differences between SHRSP and Wistar rats were quite small, because the absorbed amounts of these two sterols were much lower than those of campesterol and sitosterol. The in situ uptake of ³H-sitosterol and ¹⁴C-cholesterol solubilized in the bile salt micelle into intestinal mucosa was comparable between SHRSP and Wistar rats. These observations suggest that a mutation in Abcg5 does not greatly influence intestinal absorption of plant sterols in SHRSP rats, at least in comparison with Wistar rats.

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Oxidative stress and inflammation are related to several chronic diseases including cancer and atherosclerosis. Hibiscus sabdariffa Linnaeus has been found to possess antioxidant effects. In this study, polyphenols extracted from Hibiscus sabdariffa L. (HPE) were used to detect anti-inflammatory effects on nitrite and prostaglandin E₂ (PGE₂) in lipopolysaccharide (LPS) treated RAW264.7 cells. Sequentially, an animal model examination was performed to confirm the effects of HPE on LPS-induced hepatic inflammation. The results showed that HPE reduced 94.6% of xanthine oxidase activity in vitro, and decreased nitrite and PGE₂ secretions in LPS-induced cells. In LPS-treated rats, HPE significantly decreased the serum levels of alanine and aspartate aminotransferase. In the liver, lipid peroxidation and liver lesions decreased, and catalase activity and glutathione increased. The study also revealed that down-regulation of cyclooxygenase-2 (COX-2), p-c-Jun N-terminal kinase (p-JNK) and p-P38 might have been involved. In sum, this study found an anti-inflammatory potency of HPE both in vitro and in vivo.

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Chicken collagen hydrolysate was given to 15 mildly hypertensive subjects for 4 weeks. Blood pressure was significantly decreased by 11.8 mmHg (P<0.01). A reduction in plasma renin activity was observed in blood test after intake. A colony assay of endothelial progenitor cells in blood samples from non-smokers revealed an approximately 30% increase in the number of colonies.

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To determine the effects of ingested royal jelly (RJ) on the pituitary in middle-aged female rats, we performed a long-term RJ administration test. Several animals showed age-related increases in pituitary weight, and RJ administration compensated for the increase. RJ tended to down-regulate prolactin mRNA and up-regulated thyroid-stimulating hormone β mRNA in the pituitary. This suggests that RJ compensates for age-associated decline in pituitary functions.

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In this study, we investigated the effects of green tea (−)-epigallocatechin-3-gallate (EGCG) on the mRNA level and promoter activity of uncoupling protein 2 (UCP2), a mitochondrial membrane transporter that regulates energy expenditure and thermogenesis in 3T3-L1 adipocytes. EGCG up-regulated the UCP2 mRNA level in a dose-dependent manner. UCP2 promoter activity was significantly stimulated by EGCG treatment, to an extent similar to that seen in mRNA expression. These results suggest that expression of UCP2 gene is directly regulated by green tea EGCG, which is mediated through the transcriptional activation of its proximal promoter.

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The physiological effect of porphyran, a sulfated polysaccharides from an edible red alga, was studied in human hepatoma HepG2 cells. Porphyran supplementation significantly decreased apolipoprotein B100 secretion, and the reduction was partly associated with suppression of cellular lipid synthesis in HepG2 cells. This is the first study to elucidate the mechanism of the hypolipidemic effect of porphyran.

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The influence of lactic acid bacteria (LAB) on CD4⁺Foxp3⁺ cells has not been investigated, although it has been reported that CD4⁺Foxp3⁺ cells might be involved in the inhibition of allergic symptoms. Hence we examined the effect of orally administered LAB on CD4⁺Foxp3⁺ generation. Oral administration of Lactobacillus plantarum NRIC0380 significantly inhibited antigen-specific IgE production and enhanced the Th1 response, as some other strains reported in previous studies. The ratio of CD4⁺CD25⁺Foxp3⁺ cells in whole CD4⁺ cells was significantly higher in both Peyer’s patch and the spleen of mice that had been fed with LAB than in the control mice.

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Ginsenoside compound K was produced from ginseng root extract using a thermostable recombinant β-glycosidase from Sulfolobus solfataricus. The pH and temperature for maximum production were 5.5 and 90 °C. The half-lives of the enzyme were 66, 30, and 1.7 h at 80, 85, and 90 °C respectively. The ginsenoside-hydrolyzing activity (Rd>Rb₁>Rc>Rb₂) and compound K-producing activity (Rd>Rc>Rb₁>Rb₂) of the β-glycosidase were also determined. At pH 5.5 at 85 °C, 1.63 mg/ml of compound K was produced within 12 h by 40 U/ml of enzyme from 1.9 mg/ml of ginsenoside Rb₁, 0.52 mg/ml of ginsenoside Rb₂, 0.92 mg/ml of ginsenoside Rc, and 0.23 mg/ml of ginsenoside Rd in a 10% (w/v) ginseng root extract via two transformation pathways, Rb₁ or Rb₂ → Rd → F₂ → compound K, and Rc → compound Mc → compound K.

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Cellobiose 2-epimerase (CE, EC 5.1.3.11) catalyzes the reversible epimerization of cellobiose to 4-O-β-D-glucopyranosyl-D-mannose. In this study, we found a CE gene in the genome sequence of non-cellulolytic Bacteroides fragilis NCTC 9343. The recombinant enzyme, expressed in Escherichia coli cells, catalyzed a hydroxyl stereoisomerism at the C-2 positions of the reducing terminal glucose and at the mannose moiety of cello-oligosaccharides, lactose, β-mannobiose (4-O-β-D-mannopyranosyl-D-mannose), and globotriose [O-α-D-galactopyranosyl-(1→4)-O-β-D-galactopyranosyl-(1→4)-D-glucose]. The CE from B. fragilis showed less than 40% identity to reported functional CEs. It exhibited 44–63% identities to N-acyl-D-glucosamine 2-epimerase-like hypothetical proteins of unknown function in bacterial genome sequences of the phyla Firmicutes, Bacteroidetes, Proteobacteria, Chloroflexi, and Verrucomicrobia. On the other hand, it showed less than 26% identity to functional N-acyl-D-glucosamine 2-epimerases. Based on the amino acid homology and phylogenetic positions of the functional epimerases, we emphasize that many genes for putative N-acyl-D-glucosamine 2-epimerases and related hypothetical proteins of unknown function reported to date in the bacterial genomes should be annotated as CE-like proteins or putative CEs.

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