Blood 25-hydroxyvitamin D concentration of Japanese Black cattle at two farms with different rearing environments, Kagoshima prefecture, Japan.

Forty-two Japanese Black cattle on two farms in Kagoshima prefecture, Japan were used in this study. The rearing style of farm A was in a dark barn with a large roof to block sunlight (n=21). The rearing style of farm B was grazing, and exposed to direct sunlight (n=21).

Usefulness of magnifying endoscopy for diagnosis of sessile serrated lesion with dysplasia or carcinoma: Large retrospective study.

Sessile serrated lesions (SSLs) are precursor lesions in the serrated neoplasia pathway that lead to invasive carcinoma from dysplasia arising from SSLs. This study aimed to elucidate the clinicopathological and endoscopic features of SSLs with and without dysplasia or carcinoma. We reviewed the clinicopathological and endoscopic data from all colorectal lesions pathologically diagnosed as SSLs at Juntendo University Hospital, Tokyo, Japan, between 2011 and 2022.

The Role of Intestinal Cytochrome P450s in Vitamin D Metabolism.

Vitamin D hydroxylation in the liver/kidney results in conversion to its physiologically active form of 1,25-dihydroxyvitamin D [1,25(OH)D]. 1,25(OH)D controls gene expression through the nuclear vitamin D receptor (VDR) mainly expressed in intestinal epithelial cells. Cytochrome P450 (CYP) 24A1 is a catabolic enzyme expressed in the kidneys.

Novel physiological analysis using blood flow velocity for colonic polyps: Pilot study.

Real-time visualization of red blood cell flow inside subepithelial microvessels is performed with magnifying endoscopy. However, microvascular blood flow velocity in the colorectum has not been investigated. Here, we aimed to evaluate the blood flow velocity of microvessels of colonic polyps and to compare it with that of surrounding mucosa.

Vitamin D Promotes Not Motor Coordination but Motor Skill Learning without Influence on Muscle Function.

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.

The Association between Atherosclerotic Disease Risk Factors and Serum 25-Hydroxyvitamin D Concentration in Japanese Subjects.

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.

Apelin expression is downregulated in T cells in a murine model of chronic colitis.

Apelin (APL), an endogenous ligand for APJ, has been reported to be upregulated in a murine model of acute colitis induced by sodium dextran sulfate, as well as inflammatory bowel diseases (IBD) in humans. However, the mechanisms and functions of APL/APJ axis in the pathogenesis of IBD are unclear. We herein analyzed CD4 T cells to determine the functions of APL in a murine model of chronic colitis induced in Rag deficient mice (Rag).

Vitamin D Status in Japanese Young Women in 2016-2017 and 2020: Seasonal Variation and the Effect of Lifestyle Including Changes Caused by the COVID-19 Pandemic.

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.

Association between 25-hydroxyvitamin D levels and COVID-19 severity.

Background And Aims: Despite reports on the impact of vitamin D status on coronavirus disease 2019 (COVID-19) severity, the association between low vitamin D status and severe COVID-19 remains unclear. Moreover, researchers have not determined the aforementioned association in Japanese patients. This study aimed to investigate the association between 25-hydroxyvitamin D [25(OH)D] levels and COVID-19 severity in Japanese patients.

Development of a predictive model for vitamin D deficiency based on the vitamin D status in young Japanese women: A study protocol.

Background: Vitamin D deficiency (VDD) is associated with an increased risk for lifestyle-related diseases. In Japan, VDD is quite prevalent in all age groups, with its high risk in young women. Furthermore, its association during pregnancy with gestational hypertension and low birth weight has also been reported.

Immunoglobulin A-specific deficiency induces spontaneous inflammation specifically in the ileum.

Objective: Although immunoglobulin A (IgA) is abundantly expressed in the gut and known to be an important component of mucosal barriers against luminal pathogens, its precise function remains unclear. Therefore, we tried to elucidate the effect of IgA on gut homeostasis maintenance and its mechanism.

Design: We generated various IgA mutant mouse lines using the CRISPR/Cas9 genome editing system.

Elucidation of metabolic pathways of 25-hydroxyvitamin D3 mediated by CYP24A1 and CYP3A using Cyp24a1 knockout rats generated by CRISPR/Cas9 system.

CYP24A1-deficient (Cyp24a1 KO) rats were generated using the CRISPER/Cas9 system to investigate CYP24A1-dependent or -independent metabolism of 25(OH)D3, the prohormone of calcitriol. Plasma 25(OH)D3 concentrations in Cyp24a1 KO rats were approximately twofold higher than in wild-type rats. Wild-type rats showed five metabolites of 25(OH)D3 in plasma following oral administration of 25(OH)D3, and these metabolites were not detected in Cyp24a1 KO rats.

Comparison of Vitamin D and 25-Hydroxyvitamin D Concentrations in Human Breast Milk between 1989 and 2016-2017.

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.

A high-fat diet in the presence of vitamin D deficiency status is associated with a negative influence on calcaneal quantitative ultrasound parameters in young adults: a cross-sectional study.

Vitamin D deficiency and a high-fat diet are considered health problems worldwide. The aims of this study were to examine the prevalence of vitamin D deficiency/insufficiency in young adults, factors related to the vitamin D status, and the influence of vitamin D deficiency and/or a high-fat diet on bone parameters. Here, we investigated the hypothesis that a high-fat diet in the presence of a vitamin D-deficient status would have a more negative influence on bone parameters than a normal-fat diet with such a status.

Vitamin D in the Dietary Reference Intakes for Japanese (DRIs) 2020.

Dietary Reference Intakes for Japanese (DRIs) are revised every five years. In DRIs 2020, major revision has been made on vitamin D (VD). In DRIs, five indices are defined for nutrients; estimated average requirement (EAR), recommended dietary allowance (RDA) and adequate intake (AI) for the prevention of deficiency/insufficiency, tolerable upper intake level (UL) for avoiding excess intake, and tentative dietary goal for preventing life-style related diseases (DG) for the primary prevention of life-style related diseases.

CEACAM1 specifically suppresses B cell receptor signaling-mediated activation.

Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) expressed in T cells may regulate immune responses in the gut. In addition to T cells, B cells are also an important population in the gut-associated lymphoid tissues that orchestrate mucosal homeostasis. However, the role of CEACAM1 in B cells has not been elucidated.

Vitamin D deficiency as the risk of respiratory tract infections in the institutionalized elderly: A prospective 1-year cohort study.

Background & Aims: Respiratory tract infections (RTIs) are one of the major causes of morbidity and mortality in the elderly. Since vitamin D is known to play important roles in immunity, and its deficiency has been reported to be prevalent in the elderly, we have studied the relationship between serum 25-hydroxyvitamin D [25(OH)D] level, which is the most reliable marker for vitamin D status, and the incidence of RTIs in the institutionalized elderly by a prospective observational study.

Methods: From 208 Japanese subjects aged 60 and older fulfilling the inclusion criteria, 148 subjects remained after propensity score matching.

Vitamin K Nutrition and Bone Health.

Vitamin K is essential for blood coagulation and plays an important role in extrahepatic metabolism, such as in bone and blood vessels, and in energy metabolism. This review discusses the assessment of vitamin K sufficiency and the role of vitamin K in bone health. To elucidate the exact role of vitamin K in other organs, accurate tools for assessing vitamin K deficiency or insufficiency are crucial.

Generation of novel genetically modified rats to reveal the molecular mechanisms of vitamin D actions.

Recent studies have suggested that vitamin D activities involve vitamin D receptor (VDR)-dependent and VDR-independent effects of 1α,25-dihydroxyvitamin D (1,25(OH)D) and 25-hydroxyvitamin D (25(OH)D) and ligand-independent effects of the VDR. Here, we describe a novel in vivo system using genetically modified rats deficient in the Cyp27b1 or Vdr genes. Type II rickets model rats with a mutant Vdr (R270L), which recognizes 1,25(OH)D with an affinity equivalent to that for 25(OH)D, were also generated.

25-Hydroxyvitamin D profiles and maternal bone mass during pregnancy and lactation in Japanese women.

Vitamin D deficiency is observed worldwide and represents a health hazard for mothers, infants and elderly persons. We know that many young Japanese women experience vitamin D insufficiency; however, there is a lack of knowledge regarding the serum 25-hydroxyvitamin D [25(OH)D] profile of pregnant Japanese women and of the association between maternal 25(OH)D level and maternal bone mass during pregnancy and lactation. In this longitudinal study, 160 pregnant Japanese women were enrolled; of them, 68 have been followed-up from the first trimester through at least 1 year of breast-feeding.

Indolent T cell lymphoproliferative disorder with villous atrophy in small intestine diagnosed by single-balloon enteroscopy.

Chronic diarrhea is one of the major symptoms in gastroenterology. However, this may be caused by pathologic conditions for which the diagnosis is critical. Villous atrophy, as an endoscopic lesion, accompanied by chronic diarrhea can occasionally be observed in the patients with inflammatory diseases of the gastrointestinal (GI) tract.

Significance of urinary C-megalin excretion in vitamin D metabolism in pre-dialysis CKD patients.

Serum 1,25(OH)D and 24,25(OH)D are decreased in CKD. Megalin in proximal tubular epithelial cells reabsorbs glomerular-filtered 25(OH)D-DBP complex to convert 25(OH)D to 1,25(OH)D and 24,25(OH)D. Urinary C-megalin excretion is increased via exocytosis from injured nephrons overloaded with megalin-mediated protein metabolism.