Antioxidant Activity of β-Glucan

β-Glucans extracted from barley, which mainly contains β-(1,3-1,4)-D-glucan, are used extensively as supplements and food additives due to their wide biologic activities, including a reduction in blood lipid level. In this study, the antioxidant activity of β-glucan was examined to assess potential new benefits associated with β-glucan, because oxidative stress is considered one of the primary causal factors for various diseases and aging. β-Glucan extracted from barley was found to possess significant antioxidant activity. The amount of antioxidant activity was influenced by different physiologic properties (e.g., structure and molecular size) of β-glucan, which varied depending on the source and extraction method used. The antioxidant activity of β-glucan was significantly higher than that of various polymers that are used as food additives. These results indicate that β-glucan has promise as a polymeric excipient for supplement and food additive with antioxidant and other benefits, which may contribute to enhancing health and beauty

Action of an endo-β-1,3(4)-glucanase on cellobiosyl unit structure in barley β-1,3:1,4-glucan.

β-1,3:1,4-Glucan is a major cell wall component accumulating in endosperm and young tissues in grasses. The mixed linkage glucan is a linear polysaccharide mainly consisting of cellotriosyl and cellotetraosyl units linked through single β-1,3-glucosidic linkages, but it also contains minor structures such as cellobiosyl units. In this study, we examined the action of an endo-β-1,3(4)-glucanase from Trichoderma sp. on a minor structure in barley β-1,3:1,4-glucan. To find the minor structure on which the endo-β-1,3(4)-glucanase acts, we prepared oligosaccharides from barley β-1,3:1,4-glucan by endo-β-1,4-glucanase digestion followed by purification by gel permeation and paper chromatography. The endo-β-1,3(4)-glucanase appeared to hydrolyze an oligosaccharide with degree of polymerization 5, designated C5-b. Based on matrix-assisted laser desorption/ionization (MALDI) time-of-flight (ToF)/ToF-mass spectrometry (MS)/MS analysis, C5-b was identified as β-Glc-1,3-β-Glc-1,4-β-Glc-1,3-β-Glc-1,4-Glc including a cellobiosyl unit. The results indicate that a type of endo-β-1,3(4)-glucanase acts on the cellobiosyl units of barley β-1,3:1,4-glucan in an endo-manner.This work was supported in part by a grant-in-aid for Scientific Research to T. Kotake [Grant-in-Aid for Scientific Research no. 25514001] from Japan Society of the Promotion of Science; Y. Tsumuraya and T. Kotake [Grant-in-Aid for Scientific Research no. 24114006] from the Ministry of Education, Culture, Sports, Science, and Technology of Japan. Supports were also provided by BBSRC Sustainable Bioenergy Centre: Cell wall sugars program to P. Dupree [grant number BB/G016240/1].This is the final version of the article. It first appeared from Taylor & Francis via http://dx.doi.org/10.1080/09168451.2015.104636

Isolation and characterization of acid-soluble bluefin tuna (Thunnus orientalis) skin collagen

Abstract In this study, we isolated and characterized the acid-soluble skin collagen of Pacific bluefin tuna (PBT, Thunnus orientalis). The PBT skin collagen was composed of two α chains (α1 and α2) and one β chain. The denaturation temperature of PBT collagen was low although it was rich in proline and hydroxyproline. The primary structure of PBT skin collagen was almost identical to that of calf and salmon skin collagen; however, it differed with respect to the epitope recognition of the antibody against salmon type I collagen. These results suggest that the primary structure of skin collagen was highly conserved among animal species, although partial sequences that included the epitope structure differed among collagens

Statins enhances antitumor effect of oxaliplatin in KRAS-mutated colorectal cancer cells and inhibits oxaliplatin-induced neuropathy

Abstract Background KRAS mutations are fraught with the progression of colorectal cancer and resistance to chemotherapy. There are pathways such as extracellular regulated protein kinase 1/2 (ERK1/2) and Akt downstream and farnesylation and geranylgeranylation upstream that are activated upon mutated KRAS. Previous studies have shown that statins, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, are effective to treat KRAS mutated colorectal cancer cells. Increased doses of oxaliplatin (L-OHP), a well-known alkylating chemotherapeutic drug, causes side effects such as peripheral neuropathy due to ERK1/2 activation in spinal cords. Hence, we examined the combinatorial therapeutic efficacy of statins and L-OHP to reduce colorectal cancer cell growth and abrogate neuropathy in mice. Methods Cell survival and confirmed apoptosis was assessed using WST-8 assay and Annexin V detection kit. Detection of phosphorylated and total proteins was analyzed the western blotting. Combined effect of simvastatin and L-OHP was examined the allograft mouse model and L-OHP-induced neuropathy was assessed using cold plate and von Frey filament test. Results In this study, we examined the effect of combining statins with L-OHP on induction of cell death in colorectal cancer cell lines and improvement of L-OHP-induced neuropathy in vivo. We demonstrated that combined administration with statins and L-OHP significantly induced apoptosis and elevated the sensitivity of KRAS-mutated colorectal cancer cells to L-OHP. In addition, simvastatin suppressed KRAS prenylation, thereby enhancing antitumor effect of L-OHP through downregulation of survivin, XIAP, Bcl-xL, and Bcl-2, and upregulation of p53 and PUMA via inhibition of nuclear factor of κB (NF-κB) and Akt activation, and induction of c-Jun N-terminal kinase (JNK) activation in KRAS-mutated colorectal cancer cells. Moreover, simvastatin enhanced the antitumor effects of L-OHP and suppressed L-OHP-induced neuropathy via ERK1/2 activation in vivo. Conclusion Therefore, statins may be therapeutically useful as adjuvants to L-OHP in KRAS-mutated colorectal cancer and may also be useful in the treatment of L-OHP-induced neuropathy

Additional file 2 of Statins enhances antitumor effect of oxaliplatin in KRAS-mutated colorectal cancer cells and inhibits oxaliplatin-induced neuropathy

Additional File 2: Supplementary materials and methods

Additional file 1 of Statins enhances antitumor effect of oxaliplatin in KRAS-mutated colorectal cancer cells and inhibits oxaliplatin-induced neuropathy

Additional file 1: Fig. S1. IC50 values of L-OHP, simvastatin, or fluvastatin in colorectal cancer cell lines. Cell survival was detected by WST-8 assy. IC50 values were computed by using the survival rate data to a logistic curve. Fig. S2. Combination index values of L-OHP and simvastatin or fluvastatin in LoVo and Colon26 cells. Cell survival was detected by WST-8 assy. IC50 values were computed by using the survival rate data to a logistic curve. Fig. S3. Safety of combined treatment with L-OHP and simvastatin in mice. Male Balb/c mice (n=9 per group) were randomized and received three intravenous injections of L-OHP (6 or 10 mg/kg) or vehicle (5% glucose solution) on days 0, 7, and 14; on day 0, simvastatin was administered 12 h after L-OHP administration. Simvastatin was treated orally (p.o.) at a 10 or b 50 mg/kg once a day for 3 weeks. Mice were weighed before the first treatment and every day during the treatment period. Mean values and S.E.M. are shown. Fig. S4. Simvastatin suppressed LOHP-induced mechanical sensitivity in mice. Male Balb/c mice (n=9 per group) were randomized and received three intravenous injections of L-OHP (6 or 10 mg/kg) or vehicle (5% glucose solution) over 3 weeks (Days 0, 7, and 14). On day 0, simvastatin was administered 12 h after L-OHP administration. Simvastatin was treated orally (p.o.) at a 10 or b 50 mg/kg once a day for 3 weeks. Mechanical allodynia was analyzed using the 0.4 g von Frey filaments (Ugo Basile). Pain scores obtained from both hind paws of each mouse for five stimuli were averaged and recorded. Mean values and S.E.M. are shown. Statistical analysis was performed by ANOVA with Dunnett’s, and the difference was considered significant when P < 0.05. Fig. S5. Simvastatin suppressed LOHP-induced mechanical sensitivity in mice. Male Balb/c mice (n=9 per group) were randomized and received three intravenous injections of L-OHP (6 or 10 mg/kg) or vehicle (5% glucose solution) over 3 weeks (Days 0, 7, and 14). On day 0, simvastatin was administered 12 h after L-OHP administration. Simvastatin was treated orally (p.o.) at a 10 or b 50 mg/kg once a day for 3 weeks. Mechanical allodynia was analyzed using the 1.4 g von Frey filaments (Ugo Basile). Pain scores obtained from both hind paws of each mouse for five stimuli were averaged and recorded. Mean values and S.E.M. are shown. Statistical analysis was performed by ANOVA with Dunnett’s, and the difference was considered significant when P < 0.05. Fig. S6. Simvastatin suppressed LOHP-induced ERK1/2 phosphorylation in the lumber spinal cord of mice. Male Balb/c mice (n=5 per group) were randomized and received three intravenous injections of L-OHP (6 or 10 mg/kg) or vehicle (5% glucose solution) over 3 weeks (Days 0, 7, and 14). On day 0, simvastatin was administered 12 h after L-OHP administration. Simvastatin was treated orally (p.o.) at 10 or 50 mg/kg once a day for 3 weeks. After 3 weeks, the lumbar spinal cords of mice were quickly dissected and homogenized, and analyzed by western blot using the anti-phospho-ERK1/2 and anti-ERK1/2 antibodies. The amount of detected proteins were measured based on densitometry. The results are exemplary five independent experiments. Mean values and S.D. are shown. Statistical analysis was performed by ANOVA with Dunnett’s, and the difference was considered significant when P < 0.05

Biocompatible Polymers Modified with d‑Octaarginine as an Absorption Enhancer for Nasal Peptide Delivery

Peptide and protein drugs, which are categorized as biologics, exhibit poor membrane permeability. This pharmacokinetic disadvantage has largely restricted the development of noninvasive dosage forms of biologics that deliver into systemic circulation. We have been investigating the potential use of cell-penetrating peptide-linked polymers as a novel absorption enhancer to overcome this challenge. Since our previous study revealed that biocompatible poly­(<i>N</i>-vinylacetamide-<i>co</i>-acrylic acid) modified with d-octaarginine, a typical cell-penetrating peptide, enhanced in vitro permeation of biomolecules such as plasmid DNA and bovine serum albumin through cell membranes, the present study evaluated whether the polymers enhanced in vivo absorption of biologics applied on the mucosa. Mouse experiments demonstrated that d-octaarginine-linked polymers drastically enhanced nasal absorption of exendin-4, whose injection is clinically used. The mean bioavailability was 20% relative to subcutaneous administration, even though it fell short of 1% when exendin-4 alone was administered nasally. The absorption-enhancing function of the polymers was superior to that of sodium caprate and sodium <i>N</i>-(8-(2-hydroxybenzoyl)­amino) caprylate, which have been used for humans as an absorption enhancer. In vitro experiments using several biologics with different characteristics revealed that biologics interacted with d-octaarginine-linked polymers and were taken up into cells when incubated with the polymers. The interaction and cellular uptake were enhanced as molecular weights of the biologics increased; however, their charge-dependent in vitro performance was not clearly observed. The current data suggested that biologics formulated with our polymers became an alternative to their conventional invasive parenteral formulations