ANALYTICAL BIOCHEMISTRY
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2025
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IF 2.5
Zi-qing Wang,Li-ping Hao,Zi-xuan Meng,Hao-ran Zhang,Wei-jun Kang,Lian-feng Ai
An LC-MS/MS method was developed and validated for simultaneously quantifying 25-hydroxyvitamin D2, D3, and 1α,25-dihydroxyvitamin D3 in human serum. Protein in 200 μL serum was precipitated with acetonitrile. After centrifugation, the metabolites were derivatized using (diacetoxyiodo)benzene (PIA) and 4-(4-dimethylaminophenyl)-1,2,4-triazolidine-3,5-dione (DMAT) and then quantified by the LC-MS/MS system. The limits of detection (LODs) for the three substances were 10, 10, and 5 pg/mL, and the limits of quantification (LOQs) were 20, 20, and 10 pg/mL. The standard curves for these compounds showed linear regression coefficients (R2)>0.998 over specific concentration ranges. Recoveries were 94.36 %–102.34 % for 25(OH)D2, 92.43 %–103.41 % for 25(OH)D3, and 88.98 %–94.36 % for 1α,25(OH)2D3. The mean serum levels in 109 subjects (consisting of 61 healthy adult males and 59 healthy adult females) were 2.0 ± 1.5 ng/ml (25(OH)D2), 16.4 ± 6.1 ng/ml (25(OH)D3) and 36.6 ± 15.1 pg/ml (1α, 25(OH)2D3).Derivatization of vitamin D metabolites using PIA and DMAT is useful for rapidly determining the serum 25(OH) D2, 25(OH) D3 and 1α,25(OH)2D3 concentrations simultaneously in human serum.
研究领域:
分析化学
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临床医学
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营养学
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产品关联
DOI
PubMed
高影响因子
Stem Cell Research & Therapy
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2021
·Vol. 12
·期 1
·1-13
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IF 6.832
He Qiting,Qin Ruixi,Glowacki Julie,Zhou Shuanhu,Shi Jie,Wang Shaoyi,Gao Yuan,Cheng Lei
Background Vitamin D is important for the mineralization of bones by stimulating osteoblast differentiation of bone marrow mesenchymal stem cells (BMMSCs). BMMSCs are a target of vitamin D action, and the metabolism of 25(OH)D3 to biologically active 1α,25(OH)2D3 in BMMSCs promotes osteoblastogenesis in an autocrine/paracrine manner. Our previous study with human BMMSCs showed that megalin is required for the 25(OH)D3-DBP complex to enter cells and for 25(OH)D3 to stimulate osteoblast differentiation in BMMSCs. Furthermore, we reported that leptin up-regulates megalin in those cells. Leptin is a known inhibitor of PI3K/AKT-dependent chaperone-mediated autophagy (CMA). In this study, we tested the hypothesis that leptin acts synergistically with 25(OH)D3 to promote osteoblastogenesis in rat BMMSCs by a mechanism that entails inhibition of PI3K/AKT-dependent CMA.Methods BMMSCs were isolated from rat bone marrow (4-week-old male SD rats); qRT-PCR and western immunoblots or immunofluorescence were used to evaluate the expression of megalin, ALP, COL1A1, RUNX2, OSX, OSP, and CMA in rBMMSCs. The osteoblast differentiation was evaluated by ALP activity, ALP staining, and calcium deposition. The viability of rBMMSCs was assessed with the CCK-8 kit. Biosynthesis of 1α,25(OH)2D3 was measured by a Rat 1α,25(OH)2D3 ELISA Kit.Results The combination of leptin and 25(OH)D3 treatment significantly enhanced osteoblast differentiation as shown by ALP activity, ALP staining, and calcium deposition, the expression of osteogenic genes ALP, COL1A1, RUNX2, OSX, and OSP by qRT-PCR and western immunoblots in rBMMSCs. Leptin enhanced the expression of megalin and synthesis of 1α,25(OH)2D3 in rBMMSCs. Our data showed that leptin inhibited CMA activity of rBMMSCs by activating PI3K/AKT signal pathway; the ability of leptin to enhance 25(OH)D3 promoted osteoblast differentiation of rBMMSCs was weakened by the PI3K/AKT signal pathway inhibitor.Conclusion sOur data reveal the mechanism by which leptin and 25(OH)D3 promote osteoblast differentiation in rBMMSCs. Leptin promoted the expression of megalin by inhibiting CMA, increased the utilization of 25(OH)D3 by rBMMSCs, and enhanced the ability of 25(OH)D3 to induce osteoblast differentiation of rBMMSCs. PI3K/AKT is at least partially involved in the regulation of CMA. These data indicate the importance of megalin in BMMSCs for vitamin D’s role in skeletal health.
研究领域:
细胞生物学
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分子生物学
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内分泌学
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骨骼生物学
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产品关联
DOI
PubMed
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2026
·
IF 8.8
Yuanyuan Zhao,Yongmao Lu,Tian Yang,Shaohua Hu,Yuanyuan Yan,Xingguo Wang,Wei Wei
Multi-method strategy enhances accuracy in human milk vitamin research. • Mass spectrometry achieved precise 25(OH)D₂/₃ quantification in human milk. • Immunoassays offered rapid screening but showed a 72.98% positive bias. • Liquid chromatography profiled vitamins A and E but lacked sensitivity for D and K. • 25(OH)D₃ increased slightly, while 25(OH)D₂ declined across lactational stages. Accurate analysis of vitamin D in human milk is essential for infant nutrition but remains analytically challenging due to low levels and a complex matrix. This study evaluates a practical multi-method strategy using LC-MS/MS, ELISA, and UPLC-PDA for vitamin D analysis in human milk. LC-MS/MS precisely quantified 25(OH)D₂ and 25(OH)D₃ with assay LOQ of 0.045 ng/mL and 0.100 ng/mL, respectively. ELISA showed a 11.58 ng/mL positive bias of vitamin D which limits use for accurate quantification. UPLC-PDA profiled vitamins A and E effectively but lacked sensitivity for vitamin D. Longitudinally, LC-MS/MS results show 25(OH)D₃ and total 25(OH)D concentrations remained relatively stable, with medians ranging from 0.141 to 0.281 ng/mL and 0.263 to 0.315 ng/mL, respectively, across the study period, while 25(OH)D₂ peaked at 8 weeks before declining. This study establishes LC-MS/MS as the preferred analytical strategy for quantifying 25(OH)D 2 and 25(OH)D 3 in human milk, providing critical data to assess infant nutritional intake and guide clinical interventions. Download: Download high-res image (160KB) Download: Download full-size image
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DOI
高影响因子
Nutrition & Metabolism
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2022
·Vol. 19
·期 1
·1-9
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IF 4.654
Qiu Fubin,Li Rui,Gu Siyu,Zhao Yimin,Yang Linxue
Background Iron and vitamin D (VD) is essential to health. Previous studies have shown that iron homeostasis has a potential effect on VD metabolism, but the mechanism is not fully understood.ObjectivesTo explore the relationship between VD metabolism and iron metabolism, as well as the regulatory mechanism of iron on VD metabolism.Methods 40 male rats were fed adaptively for 7 days and randomly divided into control (C, n = 6 normal diet) group and model (M, n = 24 iron deficient diet) by simple randomization, the latter was used to establish iron deficiency anemia (IDA) model. After 6 weeks of feeding, the M group was randomly divided into: iron deficiency group (DFe), low iron group (LFe), medium iron group (MFe) and high iron group (HFe) by block randomization. Different doses of iron dextran (based on iron content (100 g·bw·d)): 0, 1.1, 3.3 and 9.9 mg) were given respectively. After 4 weeks, the rats were anesthetized with 8% chloral hydrate, Blood (collected from the abdominal aorta), liver and kidney tissues were collected. The serum and tissues were separately packed and frozen at -80℃ for testing.Results The results showed that the levels of hemoglobin (Hb), red blood cell (RBC), serum iron (SI), liver iron, and kidney iron in DFe group were lower than those in the other four groups, while the levels of total iron-binding capacity (TIBC), transferrin (TF) and transferrin receptor (Tfr) in DFe group were higher than those in other groups; The serum levels of 25-(OH)D3 and 1,25-(OH)2D3 in DFe group were significantly lower than those in C group (P < 0.05). The correlation analysis showed that the levels of 25-(OH)D3 and 1,25-(OH)2D3 were negatively correlated with TIBC, TF and Tfr no correlation with SI. Western blotting, immunofluorescence, and q-PCR results showed that compared with C group, the protein and gene expressions of CYP2R1, CYP27A1, and CYP24A1 in DFe group were down-regulated, and the expression of CYP27B1 protein and gene was up-regulated in DFe group.Conclusion Iron may be involved in the metabolism of VD3 by regulating the expression of VD3 hydroxylase, suggesting that appropriate iron supplementation might promote the activation of VD3.
研究领域:
营养学
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生物化学
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药理学
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动物生理学
✓ 已验证
DOI
PubMed
高影响因子
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