Upper Zone of Growth Plate and Cartilage Matrix (UCMA) Levels in Patients with Chronic Kidney Disease

Abstract Chronic kidney disease (CKD) is an important health problem across the world affecting the adult population with an enormous social and economic burden. Calcium regulation is also affected in patients with CKD, and related to several disorders including vascular calcifications, mineral bone disorders, and cardiovascular diseases (CVD). Upper zone of growth plate and cartilage matrix (UCMA) is vitamin K-dependent protein (VKDP) and acts as a calcification inhibitor in the cardiovascular system. The molecular mechanism of UCMA action remains unclear in CKD. In the current study, we aimed to investigate serum total UCMA levels and its association with calcium metabolism parameters in CKD patients including hemodialysis (HD) patients. Thirty-seven patients with CKD stage 3-5, 41 HD patients, and 34 healthy individuals were enrolled in this cross-sectional study. Serum UCMA and calcification related protein levels (Matrix Gla Protein (MGP), Osteocalcin (OC), and Fetuin-A) were analyzed with enzyme-linked immunosorbent assay (ELISA). Calcium mineral disorder parameters (Serum Ca, P, iPTH) were quantified with routine techniques. We, for the first time, report the potential biomarker role of UCMA in CKD including HD. Serum total UCMA levels were significantly higher in patients with CKD including HD patients than the healthy controls. Also, serum UCMA levels showed negative correlations with serum calcium, and eGFR, while showed positive relationships with P, iPTH, MGP, OC. Increased total UCMA levels may have a role in the Ca metabolism disorder and related to the pathogenesis of Vascular Calcification in patients with CKD.

Increased Chondrocyte Apoptosis in Kashin-Beck Disease and Rats Induced by T-2 Toxin and Selenium Deficiency / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate chondrocyte apoptosis and the expression of biochemical markers associated with apoptosis in Kashin-Beck disease (KBD) and in an established T-2 toxin- and selenium (Se) deficiency-induced rat model.</p><p><b>METHODS</b>Cartilages were collected from the hand phalanges of five patients with KBD and five healthy children. Sprague-Dawley rats were administered a selenium-deficient diet for 4 weeks prior to T-2 toxin exposure. The apoptotic chondrocytes were observed by terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Caspase-3, p53, Bcl-2, and Bax proteins in the cartilages were visualized by immunohistochemistry, their protein levels were determined by Western blotting, and mRNA levels were determined by real-time reverse transcription polymerase chain reaction.</p><p><b>RESULTS</b>Increased chondrocyte apoptosis was observed in the cartilages of children with KBD. Increased apoptotic and caspase-3-stained cells were observed in the cartilages of rats fed with normal and Se-deficient diets plus T-2 toxin exposure compared to those in rats fed with normal and Se-deficient diets. Caspase-3, p53, and Bax proteins and mRNA levels were higher, whereas Bcl-2 levels were lower in rats fed with normal or Se-deficiency diets supplemented with T-2 toxin than the corresponding levels in rats fed with normal diet.</p><p><b>CONCLUSION</b>T-2 toxin under a selenium-deficient nutritional status induces chondrocyte death, which emphasizes the role of chondrocyte apoptosis in cartilage damage and progression of KBD.</p>

Cotransfected human chondrocytes: over-expression of IGF-I and SOX9 enhances the synthesis of cartilage matrix components collagen-II and glycosaminoglycans

Damage to cartilage causes a loss of type II collagen (Col-II) and glycosaminoglycans (GAG). To restore the original cartilage architecture, cell factors that stimulate Col-II and GAG production are needed. Insulin-like growth factor I (IGF-I) and transcription factor SOX9are essential for the synthesis of cartilage matrix, chondrocyte proliferation, and phenotype maintenance. We evaluated the combined effect of IGF-I and SOX9 transgene expression on Col-II and GAG production by cultured human articular chondrocytes. Transient transfection and cotransfection were performed using two mammalian expression plasmids (pCMV-SPORT6), one for each transgene. At day 9 post-transfection, the chondrocytes that were over-expressing IGF-I/SOX9 showed 2-fold increased mRNA expression of the Col-II gene, as well as a 57% increase in Col-II protein, whereas type I collagen expression (Col-I) was decreased by 59.3% compared with controls. The production of GAG by these cells increased significantly compared with the controls at day 9 (3.3- vs 1.8-times, an increase of almost 83%). Thus, IGF-I/SOX9 cotransfected chondrocytes may be useful for cell-based articular cartilage therapies.

The role of MCP-1-CCR2 ligand-receptor axis in chondrocyte degradation and disease progress in knee osteoarthritis

BACKGROUND: Osteoarthritis (OA) is a common arthritic disease and multifactorial whole-joint disease. Interactions of chemokines and OA is inadequately documented. RESULTS: In vivo and in vitro studies were conducted to investigate monocyte chemoattractant protein 1 (MCP-1) and receptor chemokine (C-C motif) receptor 2 (CCR2) in chondrocyte degradation and cartilage degeneration. Chondrocytes from 16 OA patients and 6 normal controls were involved in this study. After stimulation of MCP-1, the expression of MCP-1 and CCR2 increased significantly (P < 0.001) and the expression of MMP-13 also increased (P < 0.05). MCP-1 stimulation also induced (or enhanced) the apoptosis of OA chondrocytes (P < 0.05). Additionally, the degradation of cartilage matrix markers (metalloproteinase 3 and 13, MMP3 and MMP13) in the culture medium of normal chondrocytes was also assessed. Furthermore, intra-articular injection of MCP-1 in mouse knees induced cartilage degradation and the CCR2 antagonist did not impede cartilage destroy in rats knees of monosodium iodoacetate (MIA) model. CONCLUSIONS: The results of this study demonstrate that the MCP-1-CCR2 ligand-receptor axis plays a special role in the initiation and progression of OA pathology. Patients with ambiguous etiology can gain some insight from the MCP-1-CCR2 ligand-receptor axis.

Advance on genetic mechanism of adolescent idiopathic scoliosis and genetic relationship map / 中国骨伤

Identification of genetic risk factors is the hotspot of adolescent idiopathic scoliosis (AIS). Through candidate gene approach and genome-wide association studies (GWAS), some genes were preliminary identified. To review AIS related genes,and construct the gene network map of AIS gene. We searched on NCBI PubMed and Web of Science database using search terms "adolescent idiopathic scoliosis" and "gene", to classify induction genes. We then constructed gene diagram using string-db. We found 35 AIS genes relating to connective tissue, nervous system active substances, melatonin synthesis and metabolism, puberty and growth, and genes whose function is unknown. Gene diagram shows that a network relationship between gene and other genes,in which IL6, ESR1, ESR2, VDR, TGFB1, IGF1 gene may as the key gene about AIS' genetic mechanism. Two sites of 3 GWAS results outside the network, it is suggesting new pathway that need to be explored. The study about AIS susceptibility gene is still preliminary, requiring in-depth research to identify the new networks.

A novel mutation of cartilage oligomeric matrix protein gene underlies multiple epiphyseal dysplasia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To perform mutation analysis for a female with multiple epiphyseal dysplasia (MED) and provide pre-symptomatic and prenatal diagnosis.</p><p><b>METHODS</b>Mutation screening of cartilage oligomeric matrix protein (COMP) gene was carried out through targeted next-generation DNA sequencing and Sanger sequencing.</p><p><b>RESULTS</b>A novel c.956 A>T resulting in substitution of Aspartic acid 319 for Valine (p.Asp319Val) has been identified in exon 9 of the COMP gene in the patient. As predicted by a SIFT software, above mutation can cause damage to the structure of COMP protein.</p><p><b>CONCLUSION</b>A novel c.956 A>T substitution mutation has been identified in a patient featuring MED.</p>

Study on the diagnostic value of whole-organ magnetic resonance imaging score (WORMS) in knee osteoarthritis / 中国骨伤

<p><b>OBJECTIVE</b>To explore the diagnostic value of whole-organ magnetic resonance imaging score (WORMS) in knee osteoarthritis (KOA).</p><p><b>METHODS</b>From November 2009 to January 2011,70 patients with KOA combined with knee effusion among outpatient and inpatient were analyzed retrospectively. Among the patients, 12 patients were male, 58 patients were female,ranging in age from 46 to 75 years,with a mean age of (59.66 +/- 9.93) years. The clinical symptoms were evaluated by WOMAC, the imaging of KOA was assessed by K-L score and WORMS, and COMP and CTX- II were measured respectively by ELISA. The correlation analyses and multiple linear regression analysis were studied to determine associations among biomarkers, clinical variables and radiographic findings of knee joints.</p><p><b>RESULTS</b>The average scores of WOMAC and WORMS were (57.50 +/- 8.20) and (64.54 +/- 16.45) respectively. The median of CTX- II nd COMP were 2.42 ng/ml and 4.56 ng/ml respectively. Grouped by less than the lowest quartile and more than the highest quartile of WORMS, COMP was significantly different (Z=2.04, P=0.039), but there was no significant difference in CTX-II (Z=0.79, P=0.427). WORMS were positively correlated with WOMAC and K-L score (r=0.777, P<0.01; r=0.716, P<0.01; respectively); WOMAC was also positively correlated with K-L score (r=0.692, P<0.01). WORMS's cartilage, osteophytes and synovitis were positively correlated with WOMAC, K-L score and COMP respectively (r=0.771, P<0.01; r=0.509, P<0.01; r=0.917, P<0.01). It was determined by stepwise regression that the KOA was mainly affected by WORMS, K-L score (P=0.015, P=0.025 respectively) when WOMAC as a dependent variable, age, gender, K-L score, WORMS, COMP and CTX- II as independent variables (F=20.327, P<0.01).</p><p><b>CONCLUSION</b>WORMS has a better reference value for diagnosis of KOA. The expression of COMP is high in the synovial fluid when WORMS at the high point. The clinical symptoms of knee osteoarthritis are mainly affected by WORMS and K-L score.</p>

Serum levels of cartilage oligomeric matrix protein in the diagnosis of knee osteoarthritis / 中国骨伤

<p><b>OBJECTIVE</b>To select sub-clinical patients with symptoms of knee osteoarthritis (KOA) without X-ray changes by measuring the serum level of cartilage oligomeric matrix protein (COMP) with ELISA, so as to diagnose and treat patients with knee osteoarthritis at early stage.</p><p><b>METHODS</b>The 115 patients with KOA or with symptomatic primary KOA were enrolled from August 2007 to September 2009, which was OA group; and 35 healthy people in the control group. In OA group, there were 55 males and 60 females,ranging in age from 39 to 76 years, with an average of (55 +/- 13.32) years; the body mass index (BMI) ranged from 15.1 to 29.8; the disease course ranged from 6 to 60 months. In the control group, there were 16 males and 19 females, ranging in age from 36 to 77 years, with an average of (53 +/- 12.53) years; the BMI ranged from 14.8 to 29.2. Patients with symptomatic primary knee OA of Kellgren-Lawrence (K-L) grade I-IV were evaluated. Serum level of COMP and its correlation with OA grade were analyzed by ELISA method. The patients were treated with Celecoxib capsules. The patients in OA group were followed up, and the duration ranged from 24 to 38 months (averaged, 33.4 months), and the serum level of COMP were analyzed before and after treatment.</p><p><b>RESULTS</b>The serum level of COMP in the control group varied with age (t= 2.50, P=0.02). The serum level of COMP did not correlate with gender (control group: t=0.98, P=0.34; OA group: t=0.18, P= 0.86), BMI (control group: t=0.56, P=0.92; OA group: t=0.17, P=0.85) and smoking (control group: t=1.89, P=0.08; OA group: t=0.70, P=0.49). The serum level of COMP was higher in the patients with higher K-L grades than in the patients with lower K-L grades (F=15.56, P=0.001) . The sub-clinical KOA patients without X-ray changes can be detected significant higher COMP levels than sub-clinical patients with other diseases (t=2.55, P=0.03). Therefore, according to this method, subclinical OA patients can be detected from people with other sub-clinical diseases successfully.</p><p><b>CONCLUSION</b>The serum level of COMP can be used as a potential prognostic marker to diagnose KOA.</p>

Genetic analysis and serum level of cartilage oligomeric matrix protein in patients with pseudoachondroplasia / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Pseudoachondroplasia (PSACH) is an autosomal-dominant osteochondrodysplasia due to mutations in the gene encoding cartilage oligomeric matrix protein (COMP). Clinical diagnosis of PSACH is based primarily on family history, physical examination, and radiographic evaluation. There is evidence that decreased serum COMP concentration may serve as a diagnostic marker in PSACH. Here, we investigated the role of this gene and the serum COMP concentration in Chinese patients with PSACH.</p><p><b>METHODS</b>A family with three patients and a sporadic case were recruited. Genomic and phenotypic data were recorded. The diagnosis of PSACH was made on the base of clinical evaluation. The genomic DNA was extracted from peripheral blood leukocytes. The 8-19 exons and flanking intron-exon boundary sequences of COMP were amplified by polymerase chain reaction (PCR) and screened for mutation by direct DNA sequencing. Serum COMP concentrations of 4 patients and age-compatible control group of 20 unrelated healthy subjects were analyzed on the basis of an ELISA Kit for human cartilage oligomeric matrix protein.</p><p><b>RESULTS</b>A deletion (c.1447-1455del) was identified in exon 13 in the sporadic case. The mean serum COMP concentrations of four patients (3.12+/-2.28) were significantly lower than those of control group (10.86+/-2.21, P<0.05). There was no overlap in the distribution of serum COMP concentration between PSACH patients and controls.</p><p><b>CONCLUSIONS</b>Mutations in COMP gene are responsible for the PSACH. Serum COMP concentration may be suggested as an additional diagnostic marker to aid clinical findings in suspected cases of PSACH.</p>

ADAMTS-7, a novel proteolytic culprit in vascular remodeling / 生理学报

Vascular remodeling is being recognized as a fundamental process during atherosclerosis and restenosis. Cumulative studies have demonstrated that extracellular matrix (ECM) degrading enzymes play a critical role during vascular remodeling. A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) family is a recently identified metalloproteinase family which also has capacity to degrade ECM. ADAMTS family consists of 19 members and has been linked to a variety of physiological processes including development, angiogenesis, coagulation etc. Aberrant expression or function of ADAMTS members have been implicated to many disease states such as arthritis, cancer, thrombocytopenic purpura, but barely described with regard to cardiovascular disease. This review summarizes the recent advance with respect to the role of ADAMTS-7 in vascular remodeling. We review the structure, tissue distribution, substrate, expression and regulation of ADAMTS-7, especially highlight the fine tune by ADAMTS-7 of its substrate cartilage oligomeric matrix protein (COMP) in maintaining vascular homeostasis. By use of rat carotid artery balloon injury model to mimic vascular injury in vivo, we found that ADAMTS-7 protein was accumulated preferentially in neointima and mainly localized in vascular smooth muscle cells (VSMCs). Adenovirus-elicited ADAMTS-7 overexpression greatly accelerated VSMCs migration and proliferation both in vivo and in vitro, and subsequently aggravated neointima thickening post-injury. Conversely, siRNA-mediated ADAMTS-7 knock down bona fide inhibited VSMCs migration and proliferation in cultured VSMCs and injured arteries, and ultimately ameliorated neointima area. Further studies demonstrated that ADAMTS-7 facilitated VSMCs migration through degradation of its substrate COMP. Moreover, we elucidated that COMP has the capacity to maintain the contractile phenotype of VSMCs through interacting with integrin alpha7beta1. ADAMTS-7 may therefore serve as a novel therapeutic target for atherosclerosis and postangioplasty restenosis.

Research progress of biomarker COMP in osteoarthritis / 中国骨伤

Cartilage oligomeric matrix protein (COMP) is a potential biomarker for joint destruction associated with osteoarthritis, which is first and best investigated biomarkers to reflect osteoarthritis occurs, progress and the prognosis. In this article, multiple uses and related reports of COMP are summarized briefly to promote further investigation of COMP.

Decreased circulating matrilin-1 levels in adolescent idiopathic scoliosis / 中华外科杂志

<p><b>OBJECTIVE</b>To determine the circulating matrilin-1 levels in adolescent idiopathic scoliosis (AIS), and to investigate its potential role in etiopathogenisis of AIS.</p><p><b>METHODS</b>This study population consisted of 25 patients with AIS from June 2006 to March 2007 and 25 age-matched normal controls. All subjects of the study met the following criteria: no evidence of bone diseases, metabolic diseases or growth disturbances; no evidence of systemic illness or other condition known to affect bone metabolism; and no history of recent steroid intake and surgery of congenital cardiopathy. The maximum Cobb angle and curve pattern of AIS group were recorded. All AIS patients were categorized by progressive and non-progressive groups. Progression to a severe curve was defined per usual clinical criteria (progression to a > 40 degrees curve in an individual still growing or progression to a > 50 degrees curve in an adult). Measurements of genotype by PCR-RFLP methods and circulating matrilin-1 by ELISA assay were performed in both AIS and control groups. The circulating matrilin-1 levels were compared between AIS and control groups, and also among different genotype individuals. The relationship between matrilin-1 levels and cure progression were also analyzed.</p><p><b>RESULTS</b>Compared with control group, a marked decrease of plasma matrilin-1 levels was found in AIS groups (P = 0.0002). Matrilin-1 levels of both AIS and control groups with GG genotype tended to be lower than with AA and AG genotypes, and this trend was stronger in AIS groups. Compared with non-progressive AIS group, plasma matrilin-1 levels in progressive AIS group were significantly lower.</p><p><b>CONCLUSIONS</b>There is an association between matrilin-1 levels and curve progression. Measurement of circulating matrilin-1 levels is helpful for early screening and diagnosis of AIS, and it may be considered as an independent index to predict curve progression.</p>

Association between matrilin-1 gene polymorphism and bracing effectiveness in adolescent idiopathic scoliosis girls / 中华外科杂志

<p><b>OBJECTIVES</b>To investigate the association between matrilin-1 gene polymorphism and bracing effectiveness in adolescent idiopathic scoliosis girls.</p><p><b>METHODS</b>In a prospective study, AIS girls treated with standard bracing from January 2005 to December 2008 were included and followed up. All subjects of the study met the following criteria: female; skeletally immature (Risser sign grade 0 - 3); before menarche or < 1.5 years after menarche; Cobb angle 20 degrees - 40 degrees ; scoliosis caused by congenital, neuromuscular and other cause were excluded; no evidence of bone diseases, metabolic diseases or other condition known to affect bone metabolism; no history of bracing before onset; follow-up with an interval of 3 months, and total follow-up time > 2 years. Subjects met one of the following conditions was excluded: the final follow-up time < 2 years; bad compliance (ratio of the actual daily wearing time to proposed wearing time) of bracing (< 75%); change of bracing without doctor's order. Cobb angle of major curve was recorded before the bracing initiation and at the final follow-up. A progression of 6 degrees or more was considered to be a failure of bracing. The rs1149048 polymorphism in promoter of matrilin-1 gene was chosen for genotyping by PCR-RFLP method. Differences in age at initial visit, Risser sign, Cobb angle and genotype distribution were compared between brace failure and brace success groups.</p><p><b>RESULTS</b>Seventy seven patients with AIS were included, with a mean age at (13.0 +/- 1.5) years and a mean Cobb angle at (30.3 +/- 11.9) degrees . After an average duration of 2.6 years follow-up, mean Cobb angle was 30.3 degrees +/- 11.9 degrees . There were 19 cases (24.7%) in bracing failure and 58 cases (75.3%) in bracing success. The initial Cobb angle was larger in bracing failure group compared with bracing success group (P > 0.05). Patients with double major curve were found to have the lowest bracing failure rate (19.4%), but there was no significant difference compared with other curve patterns. Bracing failure rate was marked higher in individual with genotype GG (66.7%) than that with genotype AA or AG.</p><p><b>CONCLUSIONS</b>Progression of most mild or moderate AIS can be managed by early standardized bracing treatment. It is shown that large initial Cobb angle and genotype GG of matrilin-1 gene are indicative of less bracing effectiveness.</p>

Association between polymorphism of Matrilin-1 gene (MATN1) with susceptibility to adolescent idiopathic scoliosis / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the association of matrilin-1 gene polymorphisms with adolescent idiopathic scoliosis (AIS) risk.</p><p><b>METHODS</b>This study population consisted of 419 patients with AIS and 460 healthy controls. The maximum Cobb angle of AIS patients was recorded. For initial screening, the 7 tagSNPs were genotyped in 197 cases and 172 controls. Next, we validated any significant associations in additional sample of 222 cases and 288 controls. Single-marker and haplotype analysis were employed. Genotyping was performed by PCR-RFLP method.</p><p><b>RESULTS</b>We found that allele G of rs1149048 was a significant predisposition allele of AIS (P = 0.0027, OR = 1.34 within 95% CI = 1.11 approximately 1.62), and individuals with genotype GG had a higher risk for AIS compared to AA + AG (P = 0.0008, OR = 1.61 within 95% CI = 1.22 approximately 2.12). Polymorphism of rs1149048 was also associated with curve severity in AIS patients. And a significantly higher in maximum Cobb angle was found in patients with GG genotype (P = 0.002).</p><p><b>CONCLUSIONS</b>It is concluded that the tagSNP rs1149048 polymorphism in the MATN1 promoter region is associated with both susceptibility and disease severity in AIS.</p>

Expression and significance of cartilage oligomeric matrix protein, C-X-C motif 9 and keratin 19 in oral submucosal fibrosis / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the expression and localization of cartilage oligomeric matrix protein (COMP), C-X-C motif 9 (CXCL9) and keratin 19 (KRT19) in oral submucous fibrosis (OSF) and to evaluate their roles in the pathopoiesis of OSF.</p><p><b>METHODS</b>The expression and localization of COMP, CXCL9 and KRT19 were investigated in the specimens of 66 patients with oral submucous fibrosis and 14 normal controls by immunohistochemistry, and their protein and mRNA expressions were detected by Western blotting and RT-PCR.</p><p><b>RESULTS</b>COMP was overexpressed in 36 (55%) cases of OSF, and 43 (65%) cases showed positive immunoreactivity for CXCL9 protein in the cytoplasm of inflammatory cells and endothelial cells in OSF. All normal buccal mucosa tissues were stained continuously and strongly for KRT19 in the cytoplasm of basal cells, only 7 (11%) of 66 OSF samples showed faint and fragmented KRT19 staining in the cytoplasm of basal cells. RT-PCR and Western blotting results were fully consistent with the immunohistochemical data.</p><p><b>CONCLUSIONS</b>COMP, CXCL9 and KRT19 play an important role in the pathopoiesis of OSF.</p>

Preferential expression of cartilage oligomeric matrix protein in degenerating acinar cells in chronic pancreatitis and in chronic pancreatitis-like lesions / 中华外科杂志

<p><b>OBJECTIVES</b>To study cartilage oligomeric matrix protein (COMP) mRNA and protein expression in normal pancreas, chronic pancreatitis (CP), and pancreatic cancer tissues.</p><p><b>METHODS</b>Tissues from 15 cases of normal pancreas, 14 cases of chronic pancreatitis and 14 cases of pancreatic cancer were analyzed by Northern blot, Western blot, in situ hybridization and immunohistochemistry.</p><p><b>RESULTS</b>COMP mRNA signals and immunoreactivity were strongly present in the cytoplasm of degenerating acinar cells in CP tissues as well as in CP-like lesions in pancreatic cancer tissues. In contrast, COMP expression was weak to absent in the cytoplasm of cancer cells in pancreatic cancer tissues, and in ductal cells and islet cells in normal pancreatic tissues.</p><p><b>CONCLUSION</b>COMP is preferentially expressed in degenerating acinar cells in CP and in CP-like areas in pancreatic cancer, suggesting a potential role of this molecular in acinar cell dysfunction in CP.</p>