Skin whitening and anti-corrugation activities of glycoprotein fractions from liquid extracts of boiled sea cucumber

Objective: To determine skin whitening and wrinkle improvement efficacy, glycoprotein fractions were extracted from liquid extracts of boiled sea cucumber and their effects on tyrosine and elastase inhibitory activities were assayed. Methods: Fractions above and below 50 k Da(>50 kD a and <50 kD a) were extracted via a series of steps invovling: boiling, filtering, desalting and freeze drying. Cytotoxicity, skin whitening and wrinkle-removing effects of boiled liquid were determined. Results: Our MTT data showed that neither glycoprotein fraction of boiled liquid induces cellular cytotoxicity up to a concentration of 10 mg/m L treatment of the mouse melanoma cell line, B16F10, with 10 mg/m L >50 kDa enhanced tyrosinase and elastase inhibitory activities by 50.84% and 28.78%, respectively. Correlations of the >50 kD a concentration with tyrosinase inhibitory(R^2=0.968) and elastase inhibitory(R2=0.983) efficacy were significant. Conclusions: >50 kD a glycoprotein fraction isolated from liquid extracts of boiled sea cucumber, which can serve as a functional cosmetic ingredient for whitening and wrinkle improvement of skin.

Low-intensity treadmill exercise and/or bright light promote neurogenesis in adult rat brain

The hippocampus is a brain region responsible for learning and memory functions. The purpose of this study was to investigate the effects of low-intensity exercise and bright light exposure on neurogenesis and brain-derived neurotrophic factor expression in adult rat hippocampus. Male Sprague-Dawley rats were randomly assigned to control, exercise, light, or exercise ＋ light groups （n = 9 per group）. The rats in the exercise group were subjected to treadmill exercise （5 days per week, 30 minutes per day, over a 4-week period）, the light group rats were irradiated （5 days per week, 30 minutes per day, 10 000 Ix, over a 4-week period）, the exercise ＋ light group rats were subjected to treadmill exercise in combination with bright light exposure, and the control group rats remained sedentary over a 4-week period. Compared with the control group, there was a significant increase in neurogenesis in the hippocampal dentate gyrus of rats in the exercise, light, and exercise ＋ light groups. Moreover, the expression level of brain-derived neurotrophic factor in the rat hippocampal dentate gyrus was significantly higher in the exercise group and light group than that in the control group. Interestingly, there was no significant difference in brain-derived neurotrophic factor expression between the control group and exercise ＋ light group. These results indicate that low-intensity treadmill exercise （first 5 minutes at a speed of 2 m/min, second 5 minutes at a speed of 5 m/min, and the last 20 minutes at a speed of 8 m/min） or bright-light exposure therapy induces positive biochemical changes in the brain. In view of these findings, we propose that moderate exercise or exposure to sunlight during childhood can be beneficial for neural development.

Biochemical Characterization of Soluble Acid and Alkaline Invertases from Shoots of Etiolated Pea Seedlings

Soluble invertase was purified from pea （Pisum sativum L.） by sequential procedures entailing ammonium sulfate precipitation, DEAE-Sepharose column, Con-A- and Green 19-Sepharose affinity columns, hydroxyapatite column, ultra-filtration, and Sephacryl 300 gel filtration. The purified soluble acid （SAC） and alkaline （SALK） invertases had a pH optimum of 5.3 and 7.3, respectively. The temperature optimum of two invertases was 37 ℃. The effects of various concentrations of Tris-HCI, HgCI2, and CuSO4 on the activities of the two purified enzymes were examined. Tris-HCI and HgCI2 did not affect SAC activity, whereas 10 mM Tris-HCI and 0.05 mM HgCI2 inhibited SALK activity by about 50%. SAC and SALK were inhibited by 4.8 mM and 0.6 mM CuSO4 by 50%, respectively. The enzymes display typical hyperbolic saturation kinetics for sucrose hydrolysis. The Kms of SAC and SALK were determined to be 1.8 and 38.6 mM, respectively. The molecular masses of SAC shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting were 22 kDa and 45 kDa. The molecular mass of SALK was 30 kDa. Iso-electric points of the SAC and SALK were estimated to be about pH 7.0 and pH 5.7, respectively.