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Background: Vitamin D deficiency is a major public health problem in China while there are seldom reports about vitamin D nutrition status in Chinese college students. The purpose of this study is to explore the vitamin D status of the college freshmen who came from different provinces of China and to comprehensive analyze the effects of diet, physical activity, and UV protection on serum vitamin D levels. Methods: Totally 1,667 freshmen who came from 26 provinces, autonomous districts or municipalities, were recruited into this study. An online questionnaire was used to collect the information including demographic status, diet habit, physical activity, and UV protection of the participants. Serum 25(OH)D3 concentrations were measured using a liquid chromatograph mass spectrometer. Multivariate linear regression analyses were used to explore the comprehensive influence of diet, physical activity, and UV protection on serum 25(OH)D3 levels. Results: The average age of the subjects was18.55±0.90 years, with 23.0% male and 77.0% female. The mean serum 25(OH)D3 was 18.06±6.34ng/mL and the proportion of vitamin D deficiency and insufficiency was 67.5% and 27.8%, respectively. Multivariate linear regression indicated that milk and yogurt intake≥200mL/d, calcium or vitamin D supplements and average time of outdoor activity ≥60 min/day were positively linked to higher serum vitamin D while sweets intake ≥10g/d and higher UV protection index were negatively influenced serum vitamin D after adjusted for age, gender, students’ original residence, latitudes and longitude. Conclusions: Vitamin D deficiency is an important health problem in Chinese college students. Milk and yogurt intake and outdoor activity should be encouraged while sweets intake should be limited for preventing vitamin D deficiency. Public health policies should consider well-balanced guidelines on UV protection and vitamin D food fortification or supplementation.

Background: Typical pseudogenes expressions have been reported to been associated with liver diseases. However, whether pseudogenes contribute to non-alcoholic fatty liver disease (NAFLD) and triglyceride (TG) accumulation and the underlying molecular mechanisms are poorly understood. We aimed to elucidate the role of Gm12664-201 in TG accumulation and the potential mechanism.Method and Results: We identified Gm12664-01 in high-fat diet (HFD) fed mice using microarray and confirmed its expression in both vivo and vitro high fat models with quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Then changed the level of Gm12664-201 in vitro to determine the role of it in TG accumulation, which evaluated by Oil red O staining and enzymatic method. The underlying mechanisms of Gm12664-01 in TG accumulation were investigated by detecting signaling markers BiP, PERK, ATF6, CHOP, eIF2α, XBP1 and ATF4 with qRT-PCR and western blotting. We found that Gm12664-201 was markedly increased in liver tissue of HFD mice and steric acid (SA) incubated AML-12 cells. Gm12664-201 overexpression rendered AML-12 cells susceptible to triglyceride (TG) accumulation, and silencing pseudogene Gm12664-201 expression efficiently alleviated SA-induced TG accumulation. Further studies revealed that Gm12664-201 regulates endoplasmic reticulum stress signaling markers BiP, PERK, ATF6, CHOP, eIF2α, XBP1 and ATF4 expression, which may be responsible for increased TG accumulation in hepatocytes.Conclusions: Upregulation of pseudogene Gm12664-201 induced by HFD promotes triglyceride accumulation and activates ER stress pathway in hepatocytes.

Background: Living at high latitudes is one of the risk factors for vitamin D deficiency in children. However, evidence on vitamin D improvement for this pediatric population to date is limited. This study aims at evaluating the association of different vitamin D intervention methods and outdoor activity on the vitamin D status of children in North China. Methods: In this observational study, a total of 55,925 children aged 1 month to 18 years old were recruited from pediatric outpatient departments from July 2016 to June 2017. Data on demographics, anthropometric measurements, vitamin D intervention (either prescribed by physicians or given by parents) and outdoor activity were recorded. The serum levels of 25-hydroxycholecalciferol (25(OH)D) were determined by high performance liquid chromatography tandem–mass spectrometry. Logistic regression analysis was performed to assess the association of vitamin D intervention or outdoor activity with blood vitamin D status, adjusted for age, gender, BMI for age, and seasons.Results: The overall rate of hypovitaminosis D was 65.60%. Of the children’s outdoor activity, 35.63%, 31.95%, and 32.42% were below 30min/d, 30-60 min/d and over 60min/d, respectively. Furthermore, the proportion of therapeutic intervention, supplementation intervention and no vitamin D intervention among the children was 16.48%, 32.87%, and 50.65%, respectively. After adjusted for confounding factors, vitamin D intervention was associated with a lower risk of hypovitaminosis D, with OR (95% CI) of 0.191 (0.180, 0.202) in children with therapeutic doses and 0.423 (0.404, 0.443) in those with supplementation doses, compared with children without vitamin D intervention. In addition, longer outdoor time was associated with a lower risk of hypovitaminosis D [0.479 (0.456, 0.504) for 60 min/d, 0.737 (0.701, 0.776) for 30–60 min/d], independent of vitamin D intervention. Conclusions: High prevalence of vitamin D deficiency was found in children living at high latitudes. Vitamin D intervention and outdoor activity are all negatively associated with children’s vitamin D deficiency. Routine vitamin D intervention combined with increased outdoor time might be an effective approach to prevent hypovitaminosis D among children, especially those at school, living at high latitudes.

Background: Living at high latitudes is one of the risk factors for vitamin D deficiency in children. However, evidence on vitamin D improvement for this pediatric population to date is limited. This study aims at evaluating the effect of different vitamin D intervention methods and outdoor activity on the vitamin D status of children in North China. Methods: A total of 55,925 children aged 1 month to 18 years old were recruited from pediatric outpatient departments from July 2016 to June 2017. Data on demographics, anthropometric measurements, vitamin D intervention, and outdoor activity were recorded. The serum levels of 25-hydroxycholecalciferol (25(OH)D) were determined by high performance liquid chromatography tandem–mass spectrometry. Logistic regression analysis was performed to assess the association of vitamin D intervention or outdoor activity with blood vitamin D status, adjusted for age, gender, BMI for age, and seasons.Results: The overall rate of hypovitaminosis D was 65.60%. Of the children’s outdoor activity, 35.63%, 31.95%, and 32.42% were below 30min/d, 30-60 min/d and over 60min/d, respectively. Furthermore, the proportion of therapeutic intervention, supplementation intervention and no vitamin D intervention among the children was 16.48%, 32.87%, and 50.65%, respectively. After adjusted for confounding factors, vitamin D intervention was associated with a lower risk of hypovitaminosis D, with OR (95% CI) of 0.191 (0.180, 0.202) in children with therapeutic doses and 0.423 (0.404, 0.443) in those with supplementation doses, compared with children without vitamin D intervention. In addition, longer outdoor time was associated with a lower risk of hypovitaminosis D [0.479 (0.456, 0.504) for 60 min/d, 0.737 (0.701, 0.776) for 30–60 min/d], independent of vitamin D intervention. Conclusions: High prevalence of vitamin D deficiency was found in children living at high latitudes. Vitamin D intervention and outdoor activity are all negatively associated with children’s vitamin D deficiency. Routine vitamin D intervention combined with increased outdoor time might be an effective approach to prevent hypovitaminosis D among children, especially those at school, living at high latitudes.

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Background Living at high latitudes is one of the risk factors for vitamin D deficiency in children. However, evidence on vitamin D improvement for this pediatric population to date is limited. This study aims at evaluating the effect of different supplementation methods and outdoor activity time on the vitamin D status of children in North China. Methods A total of 55,925 children aged 1 month to 18 years old were recruited from pediatric outpatient departments from July 2016 to June 2017. Data on demographics, anthropometric measurements, vitamin D supplementation, and outdoor time were recorded. The serum levels of 25-hydroxycholecalciferol (25(OH)D) were determined by high performance liquid chromatography tandem–mass spectrometry. Logistic regression analysis was performed to assess the association of vitamin D supplementation or outdoor time with blood vitamin D status, adjusted for age, gender, BMI for age, and seasons. Results The overall rate of hypovitaminosis D was 65.60%. Of the children’s outdoor time, 35.63%, 31.95%, and 32.42% were below 30 min/d, 30–60 min/d and over 60 min/d, respectively. Furthermore, the proportion of iatrogenic supplementation, voluntary supplementation and no vitamin D supplementation among the children was 16.48%, 32.87%, and 50.65%, respectively. After adjusted for confounding factors, vitamin D supplementation was associated with a lower risk of hypovitaminosis D, with OR (95% CI) of 0.191 (0.180, 0.202) in children with iatrogenic supplementation and 0.423 (0.404, 0.443) in those with voluntary supplementation, compared with children without vitamin D supplementation. In addition, longer outdoor time was associated with a lower risk of hypovitaminosis D [0.479 (0.456, 0.504) for 60 min/d, 0.737 (0.701, 0.776) for 30–60 min/d], independent of vitamin D supplementation. Conclusions High prevalence of vitamin D deficiency was found in children living at high latitudes. Vitamin D supplementation and outdoor time are all negatively associated with children’s vitamin D deficiency. Routine 25(OH)D testing combined with vitamin D supplementation might be an effective approach to prevent hypovitaminosis D among children living at high latitudes.