Functional membrane microdomains (FMMs) that are mainly composed of scaffold proteins and polyisoprenoids play important roles in diverse cellular physiological processes in bacteria. The aim of this study was to identify the correlation between MK-7 and FMMs and then regulate the MK-7 biosynthesis through FMMs. Firstly, the relationship between FMMs and MK-7 on the cell membrane was determined by fluorescent labeling. Secondly, we demonstrated that MK-7 is a key polyisoprenoid component of FMMs by analyzing the changes in the content of MK-7 on cell membrane and the changes in the membrane order before and after destroying the integrity of FMMs. Subsequently, the subcellular localization of some key enzymes in MK-7 synthesis was explored by visual analysis, and the intracellular free pathway enzymes Fni, IspA, HepT and YuxO were localized to FMMs through FloA to achieve the compartmentalization of MK-7 synthesis pathway. Finally, a high MK-7 production strain BS3AT was successfully obtained. The production of MK-7 reached 300.3 mg/L in shake flask and 464.2 mg/L in 3 L fermenter.
Bacillus subtilis/metabolism* ; Vitamin K 2/metabolism* ; Bioreactors/microbiology* ; Membrane Microdomains/metabolism*

Objective To investigate the effect of 1, 25-(OH)₂-VitD3 (VitD3) on renal tubuleinterstitial fibrosis in diabetic kidney disease. Methods NRK-52E renal tubular epithelial cells were divided into control group (5.5 mmol/L glucose medium treatment), high glucose group (25 mmol/L glucose medium treatment) and high glucose with added VitD3 group (25 mmol/L glucose medium combined with 10^-8 mmol/L VitD3). The mRNA and protein expression of Snail1, SMAD3, SMAD4, α-SMA and E-cadherin in NRK-52E cells were detected by real-time quantitative PCR and Western blot analysis respectively. The expression and localization of Snail1, SMAD3 and SMAD4 were detected by immunofluorescence cytochemical staining. The binding of Snail1 with SMAD3/SMAD4 complex to the promoter of Coxsackie-adenovirus receptor (CAR) was detected by chromatin immunoprecipitation. The interaction among Snail1, SMAD3/SMAD4 and E-cadherin were detected by luciferase assay. Small interfering RNA (siRNA) was used to inhibit the expression of Snail1 and SMAD4, and the expression of mRNA of E-cadherin was detected by real-time quantitative PCR. SD rats were randomly divided into control group, DKD group and VitD3-treated group. DKD model was established by injection of streptozotocin (STZ) in DKD group and VitD3-treated group. After DKD modeling, VitD3-treated group was given VitD3 (60 ng/kg) intragastric administration. Control group and DKD group were given normal saline intragastric administration. In the DKD group and VitD3-treated group, insulin (1-2 U/kg) was injected subcutaneously to control blood glucose for 8 weeks. The mRNA and protein levels of Snail1, SMAD3, SMAD4, α-SMA and E-cadherin in renal tissues were detected by real-time quantitative PCR and Western blot analysis respectively. Immunohistochemistry was used to detect the expression and localization of Snail1, SMAD3, SMAD4, α-SMA and E-cadherin in renal tissue. Results Compared with the control group, the mRNA and protein expressions of Snail1, SMAD3, SMAD4 and α-SMA in NRK-52E cells cultured with high glucose and in DKD renal tissues were up-regulated, while E-cadherin expression was down-regulated. After the intervention of VitD3, the expression levels of Snail1, SMAD3, SMAD4, α-SMA and E-cadherin in the DKD model improved to be close to those in the control group. Chromatin immunoprecipitation showed that Snail1 and SMAD3/SMAD4 bound to CAR promoter IV, while VitD3 prevented Snail1 and SMAD3/SMAD4 from binding to CAR promoter IV. Luciferase assay confirmed the interaction among Snail1, SMAD3/SMAD4 and E-cadherin. After the mRNA of Snail1 and SMAD4 was inhibited by siRNA, the expression of E-cadherin induced by high glucose was up-regulated. Conclusion VitD3 could inhibit the formation of Snail1-SMAD3/SMAD4 complex and alleviate the renal tubulointerstitial fibrosis in DKD.
Animals ; Rats ; Cadherins/genetics* ; Diabetes Mellitus/pathology* ; Diabetic Nephropathies/pathology* ; Epithelial-Mesenchymal Transition ; Fibrosis/pathology* ; Glucose/pharmacology* ; Kidney/pathology* ; Rats, Sprague-Dawley ; RNA, Messenger ; RNA, Small Interfering ; Transforming Growth Factor beta1/metabolism* ; Vitamin D/pharmacology*

OBJECTIVES: The excretion of urinary vitamin D-binding protein (uVDBP) is related to the occurrence and development of early-stage renal damage in patients with Type 2 diabetes (T2DM). This study aims to explore the significance of detecting uVDBP in T2DM patients and its relationship with renal tubules, and to provide a new direction for the early diagnosis of T2DM renal damage. METHODS: A total of 105 patients with T2DM, who met the inclusion criteria, were included as a patient group, and recruited 30 individuals as a normal control group. The general information and blood and urine biochemical indicators of all subjects were collected; the levels of uVDBP, and a marker of tubular injury [urine kidney injury molecule 1 (uKIM-1), urine neutrophil gelatinase-associated lipocalin (uNGAL) and urine retinol-binding protein (uRBP)] were detected by enzyme-linked immunosorbent assay. The results were corrected by urinary creatinine (Cr) to uVDBP/Cr, uKIM-1/Cr, uNGAL/Cr and uRBP/Cr. The Pearson's and Spearman's correlation tests were used to analyze the correlation between uVDBP/Cr and urine albumin-to-creatinine ratio (UACR), estimated glomerular filtration rate (eGFR) and markers of tubular injury, and multivariate linear regression and receiver operating characteristic curve were used to analyze the correlation between uVDBP/Cr and UACR or eGFR. RESULTS: Compared with the normal control group, the uVDBP/Cr level in the patient group was increased (P<0.05), and which was positively correlated with UACR (r=0.774, P<0.01), and negatively correlated with eGFR (r=-0.397, P<0.01). There were differences in the levels of uKIM-1/Cr, uNGAL/Cr, and uRBP/Cr between the 2 groups (all P<0.01). The uVDBP/Cr was positively correlated with uKIM-1/Cr (r=0.752, P<0.01), uNGAL/Cr (r=0.644, P<0.01) and uRBP/Cr (r=0.812, P<0.01). The sensitivity was 90.0% and the specificity was 82.9% (UACR>30 mg/g) for evaluation of uVDBP/Cr on T2DM patients with early-stage renal damage, while the sensitivity was 75.0% and the specificity was 72.6% for evaluation of eGFR on T2DM patients with early-stage renal damage. CONCLUSIONS The uVDBP/Cr can be used as a biomarker in early-stage renal damage in T2DM patients.
Humans ; Diabetes Mellitus, Type 2/complications* ; Creatinine ; Vitamin D-Binding Protein/urine* ; Lipocalin-2/urine* ; Kidney/metabolism* ; Glomerular Filtration Rate ; Biomarkers

OBJECTIVE: To detect variants of the MMACHC gene among 110 ethnic Han Chinese pedigrees affected with metabolic deficiency methylmalonic acidemia (MMA) of cobalamin C (cblC). METHODS: Peripheral blood samples were collected from the probands and their parents. Following DNA extraction, the coding regions of the MMACHC gene were subjected to PCR amplification, Sanger sequencing and quantitative PCR assaying. For 48 pedigrees, chorionic villus samples were taken for prenatal genetic diagnosis. RESULTS: Thirty five types of variants were detected among the 110 pedigrees, which included missense, nonsense, frameshifting, splicing variants and exonic deletions. Most variants have occurred in exons 4 (73.18%). The detection rate for c.609G>A (p.Trp203Ter) variant was the highest (33.64%), followed by c.658_660delAAG (12.27%), c.567dupT (9.09%) and c.80A>G (6.82%). Two variants, namely c.57_58insT (p.Gly20Trpfs*14) and c.505_506delAT (p.Ile169Argfs*12), were unreported previously and both were of frameshifting types. For the 48 pedigrees undergoing prenatal diagnosis, 14 fetuses were found to be normal, 24 have carried heterozygous variants, the remaining 10 have carried compound heterozygous or homozygous variants. CONCLUSION The discovery of the two novel variants has expanded the spectrum of the MMACHC gene variants among ethnic Han population. Above finding has provide a basis for the prenatal diagnosis and genetic counseling for the affected pedigrees.
Amino Acid Metabolism, Inborn Errors/genetics* ; China ; DNA ; Female ; Humans ; Mutation ; Oxidoreductases/genetics* ; Pedigree ; Pregnancy ; Prenatal Diagnosis ; Vitamin B 12/genetics*

OBJECTIVES: To study the level of serum vitamin K₂ (VitK₂) and its association with bone metabolism markers osteocalcin (OC), type I procollagen amino-terminal peptide (PINP), and type I collagen carboxy-terminal peptide (CTX) in children. METHODS: A prospective analysis was performed on 1 732 children who underwent routine physical examination from October 2020 to October 2021. The serum levels of VitK₂ and 25-hydroxy vitamin D [25(OH)D] were measured. According to age, they were divided into four groups: <1 year, 1-3 years group, >3-6 years group, and >6-14 years. A total of 309 children with 25(OH)D≥50 nmol/L were screened out, and serum levels of OC, PINP, and CTX were measured to investigate the correlation of the serum levels of OC, PINP, and CTX with serum VitK₂ levels in different age groups. RESULTS: The prevalence rate of serum VitK₂ deficiency was 52.31% (906/1 732). The VitK₂ deficiency group had higher prevalence rates of overweight/obesity and growth pain (≥3 years of age) than the normal VitK₂ group (P<0.05). There were differences in the prevalence rate of serum VitK₂ deficiency (P<0.0083) and the serum level of VitK₂ (P<0.05) between the 1-3 years group and the >6-14 years group. The <1 year group had a higher serum level of CTX and a lower serum level of PINP than the >3-6 years group and the >6-14 years group (P<0.05). The <1 year group had a lower serum level of OC than the >6-14 years group (P<0.05). Serum VitK₂ level was positively correlated with OC level (r_s=0.347, P<0.01), and CTX level was negatively correlated with PINP level (r_s=-0.317, P<0.01). CONCLUSIONS Serum VitK₂ deficiency may be associated with overweight/obesity. Serum VitK₂ may affect the level of OC and even bone health.
Child ; Humans ; Infant ; Biomarkers/metabolism* ; Collagen Type I/metabolism* ; Obesity/complications* ; Osteocalcin/metabolism* ; Overweight/complications* ; Peptide Fragments/metabolism* ; Peptides/metabolism* ; Procollagen/metabolism* ; Vitamin K/blood* ; Child, Preschool ; Adolescent ; Bone and Bones/metabolism*

With the rapid dissemination of information in modern society, Chinese residents pay more attention to the scientific concept of childcare, which makes the child prevention and health care industry develop rapidly. The law of children's growth and development is extremely complex, so it is necessary to detect different biomarkers according to different growth and development evaluation angles. Human growth hormone(hGH), insulin-like growth factor-1(IGF-1), insulin-like growth factor binding protein-3(IGFBP-3), thyroid hormone, sex hormone, anti-müllerian hormone(AMH) and 25-hydroxy vitamin D(25-OH VD) are common biomarkers to monitor children's growth and development. This article aims to explain the concept and characteristics of common biomarkers of growth and development, summarize the detection methods of common biomarkers of growth and development evaluation developed in recent years, and provide a reference for children's prevention and health care to select appropriate detection biomarkers.
Anti-Mullerian Hormone/metabolism* ; Biomarkers ; Child ; Growth and Development ; Human Growth Hormone/metabolism* ; Humans ; Insulin-Like Growth Factor Binding Protein 3 ; Insulin-Like Growth Factor I/metabolism* ; Thyroid Hormones ; Vitamin D

Objective: To detect and analyze the expression level of serum 25-hydroxyvitamin D [25(OH)D], periodontal clinical indicators and immunological indicators of rheumatism in patients with periodontitis and rheumatoid arthritis (RA), and to explore the correlation between 25(OH)D and the two diseases. Methods: This study was a case-control study. According to the inclusion criteria, patients from the Department of Stomatology and the Department of Rheumatology and Immunology and healthy volunteers from the Physical Examination Center were selected from November 2018 to May 2019 in Shengjing Hospital, China Medical University respectively. The patients were divided into 4 groups: 26 patients with simple periodontitis were included in the periodontitis group; 23 patients with RA were included in the RA group; 22 patients with RA and periodontitis simultaneously were included in the RA with periodontitis group; 22 healthy volunteers were included in the healthy control group, adding up to a total of 93 cases. The general information and periodontal clinical indexes of subjects in these 4 groups were recorded. Median elbow venous blood samples were collected from fasting subjects in each group, and 25(OH)D and immunoglobulin (Ig) were measured. The disease activity scores of RA patients were recorded and the rheumatic immune indexes were determinated. Pearson correlation analysis was performed between 25 (OH) D level and periodontal indexes in subjects of 4 groups. Results: The expression levels of rheumatoid factor [106.5(47.1, 283.8) kU/L] and C-reactive protein [20.5(13.1, 32.3) mg/L] in RA with periodontitis group were significantly higher than those in RA group [60.1(19.0, 110.0) kU/L, 14.7(3.0, 18.0) mg/L] (Z=-2.29, P=0.022; Z=-2.25, P=0.024). The levels of IgG and IgA in RA with periodontitis group [IgG and IgA: (16.0±4.3), (3.2± 1.3) g/L] as well as RA group [IgG and IgA: (16.3±5.5), (3.7±1.8) g/L] were significantly higher than those in healthy control group [IgG and IgA: (12.0±1.8), (2.3±0.6) g/L] and periodontitis group [IgG and IgA: (12.5±2.2), (2.0±0.7) g/L](P<0.05). The level of 25(OH)D in RA with periodontitis group [(26.0±9.8) nmol/L] was significantly lower than that in periodontitis group [(35.6±8.4) nmol/L] and RA group [(32.7±8.6) nmol/L] (P<0.05). The level of 25(OH)D was negatively correlated with sulcus bleeding index (r=-0.43, P=0.032) and clinical attachment loss (r=-0.41, P=0.043). Conclusions: Expression level of 25(OH)D was significantly decreased in patients with periodontitis and RA. There was a certain correlation between 25(OH)D and periodontitis and RA.
Arthritis, Rheumatoid/metabolism* ; Case-Control Studies ; Humans ; Immunoglobulin A ; Immunoglobulin G ; Periodontitis ; Vitamin D/analogs & derivatives*

Vitamin D plays an important role in mineral and bone homeostasis, immune responses, cardiovascular function and keratinocyte proliferation and differentiation. Vitamin D performs most of its functions by binding to vitamin D receptors (VDR), which interact with other intracellular signaling pathways to regulate bone metabolism, inflammation, immunity, cell cycle progression and apoptosis. Autophagy is a basic stress response in yeast, plants and mammals, and plays a critical role in maintaining optimal functional states at the level of cells and organs. Vitamin D/VDR plays an anti-infection role via inducing and regulating autophagy.
Animals ; Autophagy ; Humans ; Inflammation ; Mammals/metabolism* ; Receptors, Calcitriol/metabolism* ; Vitamin D/physiology* ; Vitamins

OBJECTIVE: To investigate the genetic etiology, clinical diagnosis and treatment of a child with pancytopenia, failure to thrive and pulmonary infection. METHODS: Peripheral blood samples of the child and her parents were collected. Genomic DNA was extracted. Genetic variants associated with hematological diseases were detected by high-throughput sequencing. RESULTS: Three variants of TCN2 gene were found, one of which located in exon 5 upstream(c.581-8A>T), the parents has carried this variant; one in exon 6 (c.924_927del), the variant was originated from the mother; one in exon 7 (c.973C>T), the variant has ocurred de novo. The variants pathogenic analysis combined with clinical manifestation, pancytopenia, the increase in methylmalonic acid level and increased homocysteine, the child was diagnosed with transcobalaminIIdeficiency. The patient presented with respiratory infection, which was confirmed to be pneumocystosis by lung radioscopy and pathogenic high-throughput sequencing of broncho-alveolar lavage fluid. The patient presented with acute respiratory distress syndrome during the treatment with intramuscular injection of vitamin B CONCLUSION We reported a case of Chinese child with TCNII deficiency due to novel gene variant, and analyzed the pathogenicity of the three variants. The treatment of TCNII deficiency with cobalamin should be individualized.
Amino Acid Metabolism, Inborn Errors ; Child ; Female ; Genetic Testing ; Humans ; Rare Diseases ; Transcobalamins/genetics* ; Vitamin B 12

Thioredoxin reductase (TrxR) is one class of the most important antioxidant selenoproteins and is involved in regulating tumor genesis and progression. It has been reported that naphthoquinones can target and inhibit TrxR1 activity therefore produce reactive oxygen species (ROS) mediated by TrxR1, resulting into cellular redox imbalance and making the naphthoquinone compounds to become potential antitumor chemotherapy drugs. The purpose of this work is to explore the interaction between TrxR1 and menadione using biochemical and mass-spectrometric (MS) analyses, to further reveal the detailed mechanisms of TrxR1-mediated naphthoquinone reduction and inhibition of TrxR1 by naphthoquinone compounds. Using the site-directed mutagenesis and recombinantly expressed TrxR1 variants, we measured the steady-state kinetic parameters of menadione reduction mediated by TrxR1 and its variants, performed the inhibition analysis of menadione on TrxR1 activity, and eventually identified the interaction between menadione and TrxR1 through MS analysis. We found that Sec-to-Cys mutation at residue of 498 significantly enhanced the efficiency of TrxR1-mediated menadione reduction, though the Sec⁴⁹⁸ is capable to catalyze the menadione reduction, indicating that TrxR1-mediated menadione reduction is dominantly in a Se-independent manner. Mutation experiments showed that Cys⁴⁹⁸ is mainly responsible for menadione catalysis in comparison to Cys⁴⁹⁷, while the N-terminal Cys⁶⁴ is slightly stronger than Cys⁵⁹ regarding the menadione reduction. LC-MS results detected that TrxR1 was arylated with one molecule of menadione, suggesting that menadione irreversibly modified the hyper-reactive Sec residue at the C-terminus of selenoprotein TrxR1. This study revealed that TrxR1 catalyzes the reduction of menadione in a Se-independent manner meanwhile its activity is irreversibly inhibited by menadione. Hereby it will be useful for the research and development of naphthoquinone anticancer drugs targeting TrxR1.
Catalysis ; Drug Development ; Oxidation-Reduction ; Thioredoxin Reductase 1/metabolism* ; Vitamin K 3/metabolism*