Biosci Biotechnol Biochem [journal]
- Daily consumption of tea catechins improves aerobic capacity in healthy male adults: a randomized double-blind, placebo-controlled, crossover trial. [JOURNAL ARTICLE]
- Biosci Biotechnol Biochem 2016 Aug 26.:1-6.
Our previous studies demonstrated that dietary supplementation with tea catechins combined with exercise improved endurance capacity in mice. This study aimed to demonstrate the effect of daily tea catechin consumption on aerobic capacity in humans. Sixteen Japanese non-athlete male subjects (aged 25-47 years) took 500 mL of a test beverage with or without tea catechins (570 mg) daily for 8 weeks and attended a training program twice a week. Aerobic capacity was evaluated by indirect calorimetry and near-infrared spectroscopy during graded cycle exercise. Catechin beverage consumption was associated with a significantly higher ventilation threshold during exercise and a higher recovery rate of oxygenated hemoglobin and myoglobin levels after graded cycle exercise when compared to subjects receiving the placebo beverage. These results indicate that daily consumption of tea catechins increases aerobic capacity when combined with semiweekly light exercise, which may be due to increased skeletal muscle aerobic capacity.
- Functional analyses of chitinases in the moss Physcomitrella patens: chitin oligosaccharide-induced gene expression and enzymatic characterization. [JOURNAL ARTICLE]
- Biosci Biotechnol Biochem 2016 Aug 26.:1-10.
Plant chitinases play diverse roles including defense against pathogenic fungi. Using reverse-transcription quantitative PCR analysis, we found that six chitinase (PpChi) genes and two genes for chitin elicitor receptor kinases (PpCERKs) are expressed at considerable levels in the moss Physcomitrella patens subsp. patens. The expressed PpChis belonged to glycoside hydrolase family 19 (class I: PpChi-Ia and -Ib; class II: PpChi-IIa and -IIc; and class IV: PpChi-IV) and to glycoside hydrolase family 18 (class V: PpChi-Vb). Treatment with chitin tetramer or hexamer increased the expression of class I and IV PpChi genes and decreased that of class II PpChi genes. Recombinant PpChi-Ia, PpChi-IV, and PpChi-Vb were characterized. PpChi-IV exhibited higher activity against chitin tetramer and pentamer than PpChi-Ia did. PpChi-Vb showed transglycosylation activity and PpChi-Ia inhibited fungal growth. These results suggest that chitinases of different classes play different roles in defense mechanism of moss plant against fungal pathogens.
- Reversible changes of canavalin solubility controlled by divalent cation concentration in crude sword bean extract. [JOURNAL ARTICLE]
- Biosci Biotechnol Biochem 2016 Aug 26.:1-8.
Canavalin is a vicilin-class (7S) storage protein found in sword bean (Canavalia gladiata). Our previous report indicated that canavalin is precipitated by the addition of 20 mM MgCl2 to crude sword bean extract. Here, we examined the solubility changes induced by the addition of Mg(2+) and Ca(2+) at various concentrations. Canavalin tended to be insolubilized at relatively low concentrations of MgCl2 (< 20 mM) and solubilized at relatively high concentrations (> 20 mM). In addition, canavalin was slightly insolubilized in the presence of NaCl. Overall, the results revealed that solubility changes are reversible and depend on the concentration of divalent cations. Therefore, we suggested a reaction scheme that describes the effects of divalent cations on the solubility of canavalin, which would facilitate the study of its physiological function and the application of canavalin in the food processing industry.
- Proteomics of Physcomitrella patens protonemata subjected to treatment with 12-oxo-phytodienoic acid. [JOURNAL ARTICLE]
- Biosci Biotechnol Biochem 2016 Aug 25.:1-8.
12-Oxo-phytodienoic acid (OPDA) is induced by mechanical wounding and suppresses the growth of Physcomitrella patens; OPDA is considered as a signal compound in this moss species. In this study, a proteomic analysis of P. patens protonemata treated with OPDA was performed. The abundance levels of 41 proteins were significantly altered by OPDA, with decreased levels for 40 proteins. The proteins for which abundance decreased in response to OPDA at the protonema developmental stage were mainly involved in the metabolism of proteins and carbohydrates. The effects of inhibition on protein abundance are likely a major physiological function of OPDA in P. patens. OPDA also suppressed the expression of histones at the protein level and gene transcription level. Suppression of histone expression might be an OPDA-specific function in P. patens protonemata. In P. patens, a subset of the physiological responses caused by OPDA is shown to differ between protonema and gametophore developmental stages.
- The amino-terminal hydrophilic region of the vacuolar transporter Avt3p is dispensable for the vacuolar amino acid compartmentalization of Schizosaccharomyces pombe. [JOURNAL ARTICLE]
- Biosci Biotechnol Biochem 2016 Aug 24.:1-7.
Avt3p, a vacuolar amino acid exporter (656 amino acid residues) that is important for vacuolar amino acid compartmentalization as well as spore formation in Schizosaccharomyces pombe, has an extremely long hydrophilic region (approximately 290 amino acid residues) at its N-terminus. Because known functional domains have not been found in this region, its functional role was examined with a deletion mutant avt3((∆1-270)) expressed in S. pombe avt3∆ cells. The deletion of this region did not affect its intracellular localization or vacuolar contents of basic amino acids as well as neutral ones. The defect of avt3Δ cells in spore formation was rescued by the expression of avt3(+) but was not completely rescued by the expression of avt3((∆1-270)). The N-terminal region is thus dispensable for the function of Avt3p as an amino acid exporter, but it is likely to be involved in the role of Avt3p under nutritional starvation conditions.
- Effect of Huperzine A on Aβ-induced p65 of astrocyte in vitro. [JOURNAL ARTICLE]
- Biosci Biotechnol Biochem 2016 Aug 24.:1-4.
Alzheimer's disease (AD) is the most common cause of dementia. Its pathology often accompanies inflammatory action, and astrocytes play important roles in such procedure. Rela(p65) is one of significant message factors in NF-κB pathway which has been reported high expression in astrocyte treated by Aβ. HupA, an alkaloid isolated from Chinese herb Huperzia serrata, has been widely used to treat AD and observations reflected that it improves memory and cognitive capacity of AD patients. To reveal its molecular mechanisms on p65, we cultured astrocytes, built Aβ-induced AD model, treated astrocytes with HupA at different concentrations, assayed cell viability with MTT, and detected p65 expression by immunohistochemistry and PCR. Our results revealed that treatment with 10 μM Aβ1-42 for 24 h induced a significant increase of NF-κB in astrocytes; HupA significantly down-regulated p65 expression induced by Aβ in astrocytes. This study infers that HupA can regulate NF-κB pathway to treat AD.
- Changes in color and texture of wheat noodles during chilled storage. [JOURNAL ARTICLE]
- Biosci Biotechnol Biochem 2016 Aug 19.:1-7.
Wheat noodles cooked for different periods of time were stored at 5 °C, and color changes in their cross sections were quantitatively assessed by digital image analysis. The color of noodles with flattened moisture distributions whitened greatly during the early stages of chilled storage due to the retrogradation of starch, with the color change showing a significant correlation with the changes in noodle fragility. Color changes were also measured for wheat noodles and noodles containing modified starch with internal moisture distributions, and local changes within the noodles were kinetically analyzed. The addition of modified starch significantly reduced the color change in the noodle interior, where the moisture content was relatively low. Scanning calorimetric measurements indicated differences in the gelatinized state of modified starch and original wheat starch at low moisture contents, which affected the rate of color change in the interior of noodles containing modified starch.
- Voluntary exercise increases IgA concentration and polymeric Ig receptor expression in the rat submandibular gland. [JOURNAL ARTICLE]
- Biosci Biotechnol Biochem 2016 Aug 8.:1-7.
Salivary IgA-a primary factor in local immunity of the oral cavity-plays an important role in maintaining local immune function in the oral cavity and prevent upper respiratory tract infections. Oral IgA levels are known to fluctuate in an exercise-dependent manner; thus, we investigated the effects of voluntary exercise on salivary IgA secretion in rats to better understand the mechanism by which this occurs. Six-week-old male Wistar rats were placed in individual cages with or without access to exercise wheels for three weeks. Notably, animals who engaged in voluntary exercise demonstrated significant increases in IgA concentration in saliva and submandibular gland tissue, as well as a markedly higher salivary IgA flow rate. Moreover, active rats also exhibited elevated polymeric Ig receptor (pIgR) mRNA expression in submandibular gland tissue. Collectively, these results suggest that voluntary exercise may increase salivary IgA concentration and boost immune function in the oral cavity.
- Anti-adipogenic effect of Glycoside St-E2 and Glycoside St-C1 isolated from the leaves of Acanthopanax henryi (Oliv.) Harms in 3T3-L1 cells. [JOURNAL ARTICLE]
- Biosci Biotechnol Biochem 2016 Aug 5.:1-10.
Acanthopanax henryi (Oliv.) Harms has been used in the treatment of arthritis, rheumatism, and abdominal pain. This study evaluated whether natural compounds isolated from the leaves of A. henryi (Oliv.) Harms could inhibit adipocyte differentiation by regulating transcriptional factors such as peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα). AMP-activated protein kinase (AMPK) activity was also evaluated. Among the several compounds isolated from the leaves of A. henryi (Oliv.) Harms, Glycoside St-C1 and Glycoside St-E2 significantly decreased lipid accumulation and the expressions of PPARγ and C/EBPα. Glycoside St-C1 and Glycoside St-E2 were found to activate AMPK when they regulated PPARγ and C/EBPα. Results confirmed that Glycoside St-C1 and Glycoside St-E2 isolated from the leaves of A. henryi (Oliv.) Harms can inhibit adipogenesis through the AMPK-PPARγ-C/EBPα mechanism. Thus, this study suggests that Glycoside St-C1 and Glycoside St-E2 have a therapeutic effect due to activation of the AMPKα.
- Tyrosinase inhibitory flavonoid from Juniperus communis fruits. [JOURNAL ARTICLE]
- Biosci Biotechnol Biochem 2016 Aug 5.:1-7.
The fruits of Juniperus communis have been traditionally used in the treatment of skin diseases. In our preliminary experiment, the MeOH extract of J. communis effectively suppressed mushroom tyrosinase activity. Three monoflavonoids and five biflavonoids were isolated from J. communis by bioassay-guided isolation and their inhibitory effect against tyrosinase was evaluated. According to the results of all isolates, hypolaetin 7-O-β-xylopyranoside isolated from J. communis exhibited most potent effect of decreasing mushroom tyrosinase activity with an IC50 value of 45.15 μM. Further study provided direct experimental evidence for hypolaetin 7-O-β-D-xylopyranoside-attenuated tyrosinase activity in α-MSH-stimulated B16F10 murine melanoma cell. Hypolaetin 7-O-β-D-xylopyranoside from the EtOAc fraction of J. communis was also effective at suppressing α-MSH-induced melanin synthesis. This is the first report of the enzyme tyrosinase inhibition by J. communis and its constituent. Therapeutic attempts with J. communis and its active component, hypolaetin 7-O-β-D-xylopyranoside, might be useful in treating melanin pigmentary disorders.