The increasing prevalence of aging has led to a rising incidence of comorbidity of sarcopenia and obesity, posing significant burdens on socioeconomic and public health. Current research has systematically explored the pathogenesis of each condition; however, the mechanisms underlying their comorbidity remain unclear. This study reviews the current literature on sarcopenia and obesity in the aging population, focusing on their shared biological mechanisms, which include loss of autophagy, abnormal macrophage function, mitochondrial dysfunction, and reduced sex hormone secretion. It also identifies metabolic mechanisms such as insulin resistance, vitamin D metabolism abnormalities, dysregulation of iron metabolism, decreased levels of nicotinamide adenine dinucleotide, and gut microbiota imbalances. Additionally, this study also explores the important role of genetic factors, such as alleles and microRNAs, in the co-occurrence of sarcopenia and obesity. A better understanding of these mechanisms is vital for developing clinical interventions and preventive strategies.
Humans ; Sarcopenia/physiopathology* ; Obesity/physiopathology* ; Aging/physiology* ; Autophagy/physiology* ; Insulin Resistance ; Comorbidity ; Vitamin D/metabolism* ; Gonadal Steroid Hormones/metabolism* ; Gastrointestinal Microbiome ; Mitochondria ; MicroRNAs

Bone tuberculosis is one of the main lesions of extrapulmonary tuberculosis, and the affected site shows local pain and limited movement, and the severe patients face a higher risk of teratogenicity and disability. Especially in the context of the increasing spread of multidrug-resistant tuberculosis, it is particularly urgent to seek innovative treatment options. In recent years, vitamin D plays an important role in the prevention and treatment of bone tuberculosis, and the mechanism of action has been continuously explored. At the same time, vitamin D receptor gene polymorphism has also been found to be closely related to the susceptibility and risk of bone tuberculosis. This article reviewed the relationship between vitamin D and its receptor gene polymorphisms and the susceptibility to bone tuberculosis. It was found that vitamin D deficiency increased the susceptibility to bone tuberculosis in both adults and children, and multiple genotypes of vitamin D receptor had an effect on the susceptibility to bone tuberculosis, especially FokⅠ genotype. It may also be one of the reasons for the increase in the number of bone tuberculosis. Through the study of the relationship between vitamin D and its receptor gene polymorphism and the susceptibility to bone tuberculosis, some factors inducing bone tuberculosis can be avoided, and related new drugs can be more targeted, such as vitamin D supplements, gene receptor related antagonists, etc. To provide more systematic and targeted strategies for the prevention and treatment of bone tuberculosis.
Humans ; Receptors, Calcitriol/genetics* ; Genetic Predisposition to Disease ; Polymorphism, Genetic ; Vitamin D/metabolism* ; Tuberculosis, Osteoarticular/metabolism*

OBJECTIVE: To investigate the characteristics of Vitamin D (VitD) and bone metabolism in patients with knee osteoarthritis (KOA) concurrent with osteoporosis (OP). METHODS: A retrospective analysis was performed on 240 patients who were admitted to the orthopedics department between March 2019 and March 2024. Patients were stratified into four distinct groups according to their respective disease categories.There were 90 patients in the simple KOA group, comprising 13 males and 77 females, age ranged from 50 to 91 years old with an average of (68.48±8.96) years old. There were 90 patients in the simple OP group, comprising 7 males and 83 females, age ranged from 52 to 88 years old with an average of (69.60±8.94 )years old. There were 30 patients in the KOA with OP group, comprising 1 male and 29 females, age ranged from 51 to 91 years old with an average of(69.03±7.93) years old. There were 30 patients in the physical examination group, comprising 5 males and 25 females, age ranged from 53 to 79 years old with an average of(64.93±6.51) years old. The general data and the levels of osteocalcin (OC), β-CrossLaps, parathyroid hormone(PTH) and VitD in each group were observed. RESULTS: The level of VitD in KOA with OP group (19.62±10.38) ng·ml^-1 and OP group (20.65±10.50) ng·ml^-1 was lower than that in physical examination group (27.46±8.00) ng·ml^-1 and KOA group (24.01±9.11) ng·ml^-1 (P<0.05). There were significant differences in β- CrossLaps and PTH levels among the four groups (P<0.001, P=0.019, respectively), while there was no significant difference in OC levels (P=0.763). Compared with the two simple disease groups, the KOA with OP group had higher levels of β - CrossLaps(0.81±0.30) ng·ml^-1 (P<0.001). There were significant differences in β-CrossLaps and PTH between the simple KOA group(0.54±0.22) ng·ml^-1, (46.03±18.08) pg·ml^-1 and the physical examination group (0.44±0.19) ng·ml^-1, (36.65±9.63) pg·mL^-1(P=0.038;P=0.006). There was a significant difference in PTH between the OP group(43.85±14.30) ng·ml-1, and the physical examination group, P=0.004. There was a significant difference in Kallgren-Lawrence grading between KOA with OP group and KOA group (P=0.006). Within KOA with OP group, the differences of β-CrossLaps and VitD levels among different K-L grades were statistically significant (P=0.016). The level of OC, β-CrossLaps and PTH within KOA with OP group was significantly different at different VitD levels (P=0.013, P=0.033, P=0.046). CONCLUSION Patients with KOA complicated by OP exhibit greater disturbances in bone metabolism and reduced VitD levels, particularly reflected by elevated β-CrossLaps. These findings underscore the importance of early monitoring of bone turnover and VitD supplementation in advanced-stage KOA with bone loss.
Humans ; Female ; Male ; Middle Aged ; Aged ; Vitamin D/blood* ; Osteoporosis/complications* ; Aged, 80 and over ; Osteoarthritis, Knee/complications* ; Retrospective Studies ; Bone and Bones/metabolism* ; Parathyroid Hormone/metabolism* ; Osteocalcin/metabolism*

OBJECTIVES: To investigate the correlation between bone mineral density (BMD) and bone metabolic markers in preschool children and the influencing factors for BMD, and to provide a clinical basis for promoting bone health in children. METHODS: A retrospective analysis was performed for the data of 127 preschool children who underwent physical examination in the Department of Child Health Care of the First Affiliated Hospital of Xinjiang Medical University, from June to December 2024. BMD and bone metabolic markers were measured, and physical examination was performed. A multiple linear regression analysis was used to investigate the effect of general information on BMD Z-score in preschool children. Spearman's rank correlation test was used to investigate the correlation of BMD Z-score with 25-hydroxyvitamin D (25-OHD), serum bone Gla protein (BGP), and parathyroid hormone (PTH). RESULTS: BMD Z-score significantly differed by ethnicity, weight category, and height category (all P<0.05). The multiple linear regression analysis indicated that weight and height significantly influenced BMD Z-score (P<0.05), whereas sex, age, ethnicity, and parental education level did not (P>0.05). In children, BMD Z-score was positively correlated with 25-OHD level (r_s=0.260, P<0.001) and BGP level (r_s=0.075, P=0.025) and was negatively correlated with PTH level (r_s=-0.043, P=0.032). CONCLUSIONS Weight, height, 25-OHD, BGP, and PTH are influencing factors for BMD in preschool children. In clinical practice, combined measurement of bone metabolic markers may provide a scientific basis for early identification of children with abnormal BMD and prevention of osteoporosis and osteomalacia.
Humans ; Bone Density ; Child, Preschool ; Female ; Male ; Retrospective Studies ; Vitamin D/blood* ; Parathyroid Hormone/blood* ; Biomarkers/blood* ; Osteocalcin/blood* ; Bone and Bones/metabolism* ; Calcium-Binding Proteins/blood* ; Linear Models ; Matrix Gla Protein ; Extracellular Matrix Proteins/blood* ; Body Weight ; Infant

OBJECTIVES: To investigate the changes in blood levels of calcium and bone metabolism biochemical markers in patients with primary osteoporosis receiving treatment with denosumab. METHODS: Seventy-three patients with primary osteoporosis treated in our Department between December, 2021 and December 2023 were enrolled. All the patients were treated with calcium supplements, vitamin D and calcitriol in addition to regular denosumab treatment every 6 months. Blood calcium, parathyroid hormone (PTH), osteocalcin (OC), type I procollagen amino-terminal propeptide (PINP), and type I collagen carboxy-terminal telopeptide β special sequence (β‑CTX) data before and at 3, 6, 9, and 12 months after the first treatment were collected from each patient. RESULTS: Three months after the first denosumab treatment, the bone turnover markers (BTMs) OC, PINP, and β-CTX were significantly decreased compared to their baseline levels by 39.5% (P<0.001), 56.2% (P<0.001), and 81.8% (P<0.001), respectively. At 6, 9, and 12 months of treatment, OC, PINP, and β-CTX remained significantly lower than their baseline levels (P<0.001). Blood calcium level was decreased (P<0.05) and PTH level increased (P<0.05) significantly in these patients at months of denosumab treatment, but their levels were comparable to the baseline levels at 6, 9, and 12 months of the treatment (P>0.05). CONCLUSIONS Denosumab can suppress BTMs and has a good therapeutic effect in patients with primary osteoporosis, but reduction of blood calcium and elevation of PTH levels can occur during the first 3 months in spite of calcium supplementation. Blood calcium and PTH levels can recover the baseline levels as the treatment extended, suggesting the importance of monitoring blood calcium and PTH levels during denosumab treatment.
Humans ; Denosumab/therapeutic use* ; Calcium/blood* ; Parathyroid Hormone/blood* ; Biomarkers/blood* ; Osteoporosis/blood* ; Osteocalcin/blood* ; Procollagen/blood* ; Female ; Collagen Type I/blood* ; Peptide Fragments/blood* ; Bone Density Conservation Agents/therapeutic use* ; Bone and Bones/metabolism* ; Male ; Middle Aged ; Vitamin D ; Peptides/blood* ; Aged

SoxR, one of bacterial transcriptional regulators, plays a crucial role in bacterial responses to oxidative stress induced by unfavorable environmental conditions. So far, the understanding of bacterial responses to oxidative stress mainly stems from a handful model bacteria such as Escherichia coli and the studies on non-model bacterial responses to oxidative stress are limited. In this study, Citrobacter braakii JPG1, a commonly occurring strain of enterobacteria, was used as a model for the first time to explore the role of SoxR in the responses to aerobic/anaerobic-menadione stress. First, we analyzed the phylogenetic relationship of SoxR based on the whole genome and constructed the soxR-deleted strain (ΔsoxR). Then, the cell counts of the wild type (WT) and ΔsoxR were compared under aerobic/anaerobic-menadione stress. The results showed that the cell count of WT exposed to the aerobic-low concentration menadione (0.1 mmol/L) stress for 24 h increased by 4.2 times compared with that at the time point of 0 h, while that of ΔsoxR only increased by 1.3 times. The vast majority of WT and ΔsoxR cells died after exposure to the aerobic-high concentration menadione (0.3 mmol/L) stress for 24 h, with the cell counts only 29% and 0.2% of those at the time point of 0 h, respectively. Interestingly, the cell counts of WT showed no significant difference between the anaerobic-menadione stress and the control (P > 0.05), and the same was true for ΔsoxR. All these results indicated that SoxR of C. braakii JPG1 only has a regulatory effect on the redox cycling compound menadione under aerobic conditions and enhance the antioxidant capacity. Under anaerobic conditions, menadione failed to activate SoxR. The findings from this study provide new insights into understanding both the physiological responses to menadione stress and the regulatory role of SoxR under different oxygen conditions.
Bacterial Proteins/physiology* ; Anaerobiosis ; Aerobiosis ; Vitamin K 3/pharmacology* ; Citrobacter/metabolism* ; Transcription Factors/physiology* ; Oxidative Stress ; Gene Expression Regulation, Bacterial

Scavenger receptor class B, member 2 (SCARB2) is linked to Gaucher disease and Parkinson's disease. Deficiency in the SCARB2 gene causes progressive myoclonus epilepsy (PME), a rare group of inherited neurodegenerative diseases characterized by myoclonus. We found that Scarb2 deficiency in mice leads to age-dependent dietary lipid malabsorption, accompanied with vitamin E deficiency. Our investigation revealed that Scarb2 deficiency is associated with gut dysbiosis and an altered bile acid pool, leading to hyperactivation of FXR in intestine. Hyperactivation of FXR impairs epithelium renewal and lipid absorption. Patients with SCARB2 mutations have a severe reduction in their vitamin E levels and cannot absorb dietary vitamin E. Finally, inhibiting FXR or supplementing vitamin E ameliorates the neuromotor impairment and neuropathy in Scarb2 knockout mice. These data indicate that gastrointestinal dysfunction is associated with SCARB2 deficiency-related neurodegeneration, and SCARB2-associated neurodegeneration can be improved by addressing the nutrition deficits and gastrointestinal issues.
Animals ; Mice ; Dysbiosis/metabolism* ; Mice, Knockout ; Humans ; Lysosomal Membrane Proteins/genetics* ; Receptors, Scavenger/genetics* ; Gastrointestinal Microbiome ; Myoclonic Epilepsies, Progressive/genetics* ; Vitamin E Deficiency/complications* ; Neurodegenerative Diseases/genetics* ; Bile Acids and Salts/metabolism* ; Male ; Lipid Metabolism ; Intestinal Mucosa/pathology*

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

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*