Publications by authors named "Honami Ogasawara"

Although motor coordination or motor skill learning are improved by taking vitamin D in the animal experiment, muscle function have not been estimated. Here we examined the effect of vitamin D administration on motor coordination and motor skill learning, muscle strength, and muscle volume in mice fed a vitamin D deficient diet. In mice fed a vitamin D deficient diet, serum calcium and 25(OH)D concentrations were measured.

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Recent studies have described that vitamin D deficiency/insufficiency is associated with hypertension, insulin resistance, and dyslipidemia, which are major components of metabolic syndrome causing atherosclerosis. Therefore, we investigated the relationship between serum 25-hydroxyvitamin D [25(OH)D] concentration and atherosclerotic disease risk factors in healthy Japanese adults. In the present cross-sectional study, 1,177 subjects (348 males and 829 females) aged 20-72 y living in Japan (34.

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Avoidance of sunlight and self-restraint due to the COVID-19 pandemic may contribute to reduced vitamin D status. This study provides comparable data on vitamin D status in Japanese young women and assesses the effect of lifestyle, including changes caused by the COVID-19 pandemic, on vitamin D status. In study 1, 39 young healthy Japanese women aged 21-25 y were recruited from May 2016-June 2017.

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Background: Breast milk is considered the optimal source of nutrition during infancy. Although the vitamin D concentration in human breast milk is generally considered poor for infants, vitamin D in breast milk is an important source for exclusively breastfed infants. Increases in vitamin D insufficiency and deficiency in lactating mothers may reduce vitamin D concentrations in breast milk.

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Vitamin D is a fat-soluble vitamin that is metabolized by the liver into 25-hydroxyvitamin D [25(OH)D] and then by the kidney into 1,25-dihydroxyvitamin D [1,25(OH)D], which activates the vitamin D receptor expressed in various cells, including immune cells, for an overall immunostimulatory effect. Here, to investigate whether oral supplementation of 25-hydroxyvitamin D [25(OH)D], a major form of vitamin D metabolite 25(OH)D, has a prophylactic effect on influenza A virus infection, mice were fed a diet containing a high dose of 25(OH)D and were challenged with the influenza virus. In the lungs of 25(OH)D-fed mice, the viral titers were significantly lower than in the lungs of standardly fed mice.

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Vitamin D deficiency (VDD) is associated with an increased risk of various diseases. Serum 25-hydroxyvitamin D [25(OH)D] concentration is the best marker for vitamin D status and its concentration < 20 ng/mL indicates VDD. However, its measurement is not easily applicable for the evaluation of vitamin D status in the general population because of its cost.

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