A Simplified Questionnaire for the Assessment of Inorganic Arsenic Intake in a Japanese Population

A simplified questionnaire was developed to assess inorganic arsenic (iAs) intake level in a Japanese population. The two page questionnaire included photographs of single serving sizes of rice and cooked hijiki (Hizikia fusiforme: brown algae), and asked subjects about the number of servings of rice and cooked hijiki, two predominant dietary sources of iAs in Japan, they consume in a day. Daily intake of iAs was estimated for 72 Japanese subjects using the questionnaire together with data of iAs content in rice and hijiki seaweed, and the estimated intakes were compared with actual iAs intakes of the subjects as measured for a duplicate diet using liquid chromatography–inductively coupled plasma mass spectrometry. A highly significant correlation was found between the estimated and measured intakes (r = 0.65, p < 0.001); however, the slope of regression indicated a systematic error in the intake estimation. Possible sources of error are discussed herein. It was concluded that this approach is promising if minor improvements are made to the questionnaire.

Anti-Photoaging and Anti-Melanogenesis Effects of Fucoidan Isolated from Hizikia fusiforme and Its Underlying Mechanisms

Previous studies suggested that fucoidan with a molecular weight of 102.67 kDa, isolated from Hizikia fusiforme, possesses strong antioxidant activity. To explore the cosmeceutical potential of fucoidan, its anti-photoaging and anti-melanogenesis effects were evaluated in the present study. The anti-photoaging effect was investigated in ultraviolet (UV) B-irradiated human keratinocytes (HaCaT cells), where fucoidan effectively reduced the intracellular reactive oxygen species level and improved the viability of the UVB-irradiated cells without any cytotoxic effects. Moreover, fucoidan significantly decreased UVB-induced apoptosis in HaCaT cells by regulating the protein expression of Bax, Bcl-xL, PARP, and Caspase-3 in HaCaT cells in a concentration-dependent manner. The anti-melanogenesis effect of fucoidan was evaluated in B16F10 melanoma cells that had been stimulated with alpha-melanocyte-stimulating hormone (α-MSH), and fucoidan treatment remarkably inhibited melanin synthesis in α-MSH-stimulated B16F10 cells. Further studies indicated that fucoidan significantly suppressed the expression of tyrosinase and tyrosinase-related protein-1 and -2 (TRP-1 and-2) in B16F10 cells by down-regulating microphthalmia-associated transcription factor (MITF) through regulation of the ERK–MAPK (extracellular signal regulated kinase-mitogen activated protein kinase) pathway. Taken together, these results suggest that fucoidan isolated from H. fusiforme possesses strong anti-photoaging and anti-melanogenesis activities and can be used as an ingredient in the pharmaceutical and cosmeceutical industries.