BMSC-Derived Exosomes Attenuate Rat Osteoarthritis by Regulating Macrophage Polarization through PINK1/Parkin Signaling Pathway.

OBJECTIVE: Exosomes derived from bone marrow mesenchymal stem cells (BMSC-Exos) may modulate the M1/M2 polarization of macrophages during osteoarthritis (OA). However, the underlying mechanisms of BMSC-Exos in this process still need to be elucidated. In this study, we explored the role of BMSC-Exos in the polarization of macrophages in vitro and the OA rats in vivo. METHODS: The effects of BMSC-Exos on RAW264.7 cells were determined, including the production of reactive oxygen species (ROS) and the protein expression of Akt, PINK1, and Parkin. We prepared an OA model by resecting the anterior cruciate ligament and medial meniscus of Sprague-Dawley (SD) rats. Hematoxylin-eosin (H&E) and safranin O-fast green staining, immunohistochemistry and immunofluorescence analyses, and the examination of interleukin 6 (IL-6), interleukin 1ß (IL-1ß), tumor necrosis factor alpha (TNF-α), and interleukin 10 (IL-10) were performed to assess changes in cartilage and synovium. RESULTS: BMSC-Exos inhibited mitochondrial membrane damage, ROS production, and the protein expression of PINK1 and Parkin. Akt phosphorylation was downregulated under lipopolysaccharide (LPS) induction but significantly recovered after treatment with BMSC-Exos. BMSC-Exos alleviated cartilage damage, inhibited M1 polarization, and promoted M2 polarization in the synovium in OA rats. The expression of PINK1 and Parkin in the synovium and the levels of IL-6, IL-1ß, and TNF-α in the serum decreased, but the level of IL-10 increased when BMSC-Exos were used in OA rats. CONCLUSION: BMSC-Exos ameliorate OA development by regulating synovial macrophage polarization, and one of the underlying mechanisms may be through inhibiting PINK1/Parkin signaling.

Dihydrotanshinone I protects human chondrocytes and alleviates damage from spontaneous osteoarthritis in a guinea pig model.

Osteoarthritis (OA) is the most common degenerative joint disease. Currently, no satisfactory pharmacological treatment exists for OA. The potential anti-inflammatory properties of Dihydrotanshinone I (DHT) have been reported, but its effects on OA are unclear. In this study, we assess the impact of DHT on the viability of human chondrocytes in vitro. We then use a guinea pig model to investigate the effects of DHT on knee osteoarthritis progression. Twelve-week-old Dunkin Hartley guinea pigs spontaneously developing OA were intraperitoneally injected with different doses of DHT for eight weeks. Micro-CT analysis was performed on the subchondral bone in the knee, and histological assessment of the knee joint was done using stained sections, the ratio of hyaline to calcified cartilage, and Mankin scores. DHT successfully restored IL-1ß-induced decreases in cell viability in human primary chondrocytes. In the guinea pig model, intraperitoneal injections of DHT ameliorated age-induced OA, effectively reduced the expression level of two cartilage metabolism-related genes (ADAMTS4 and MMP13) and decreased the inflammatory biomarker IL-6 in the serum of guinea pigs developing spontaneous osteoarthritis. These findings demonstrate DHT's protective effects on chondrocytes and suggest that it alleviates cartilage degradation and proteoglycan loss in OA.

ERK-estrogen receptor α signaling plays a role in the process of bone marrow mesenchymal stem cell-derived exosomes protecting against ovariectomy-induced bone loss.

BACKGROUND: Exosomes derived from bone marrow mesenchymal stem cells (BMSC-Exos) are considered as candidates for osteoporosis (OP) therapy. Estrogen is critical in the maintenance of bone homeostasis. However, the role of estrogen and/or its receptor in BMSC-Exos treatment of OP, as well as its methods of regulation during this process remain unclear. METHODS: BMSCs were cultured and characterized. Ultracentrifugation was performed to collect BMSC-Exos. Transmission electron microscopy, nanoparticle tracking analysis, and western blotting were used to identify BMSC-Exos. We examined the effects of BMSC-Exos on the proliferation, osteogenic differentiation, mineralization, and cell cycle distribution of MG-63 cells. The protein expression of estrogen receptor α (ERα) and the phosphorylation of ERK were investigated through western blotting. We determined the effects of BMSC-Exos on the prevention of bone loss in female rats. The female Sprague-Dawley rats were divided into three groups: the sham group, ovariectomized (OVX) group, and the OVX + BMSC-Exos group. Bilateral ovariectomy was performed in the OVX and OVX + BMSC-Exos groups, while a similar volume of adipose tissue around the ovary was removed in the sham group. The rats in OVX group and OVX + BMSC-Exos group were given PBS or BMSC-Exos after 2 weeks of surgery. Micro-CT scanning and histological staining were used to evaluate the in vivo effects of BMSC-Exos. RESULTS: BMSC-Exos significantly enhanced the proliferation, alkaline phosphatase activity, and the Alizarin red S staining in MG-63 cells. The results of cell cycle distribution demonstrated that BMSC-Exos increased the proportion of cells in the G2 + S phase and decreased the proportion of cells in the G1 phase. Moreover, PD98059, an inhibitor of ERK, inhibited both the activation of ERK and the expression of ERα, which were promoted by administration of BMSC-Exos. Micro-CT scan showed that in the OVX + BMSC-Exos group, bone mineral density, bone volume/tissue volume fraction, trabecular number were significantly upregulated. Additionally, the microstructure of the trabecular bone was preserved in the OVX + BMSC-Exos group compared to that in the OVX group. CONCLUSION: BMSC-Exos showed an osteogenic-promoting effect both in vitro and in vivo, in which ERK-ERα signaling might play an important role.

Identification of Biomarker IL2Rß in Ankylosing Spondylitis via Multi-Chip Integration Analysis of Gene Differential Expression.

BACKGROUND: Ankylosing spondylitis (AS) is a chronic inflammatory autoimmune disease that affects axial joints such as the spine. Early diagnosis is essential to improve treatment outcomes. The purpose of this study is to uncover underlying genetic diagnostic features of AS. METHODS: We downloaded gene expression data from the Gene Expression Omnibus (GEO) database for three studies of groups of healthy and AS samples. After preprocessing and normalizing the data, we employed linear models to identify significant differentially expressed genes (DEGs) and further integrated the differential genes to acquire reliable differential transcriptional markers. Gene functional enrichment analysis was conducted to obtain enriched pathways and regulatory gene interactions were extracted from pathways to further elucidate pathway networks. Seventy-three reliably differentially expressed genes (DEGs) were integrated by differential analysis. Utilizing the regulatory relationships of the 21 Kyoto Encyclopedia of Genes and Genomes (KEGG) Pathway genes that were enriched in the analysis, a regulatory network of 622 genes was constructed and its topological properties were further analyzed. RESULTS: Functional enrichment analysis found 73 DEGs that were strongly associated with immune pathways like Th17, Th1 and Th2 cell differentiation. Using KEGG combined with DEGs, six hub genes (KLRD1, HLA-DRB3, HLA-DRB5, IL2Rß, CD247, and CXCL10) were suggested from the network. Of these, the IL2Rß gene was significantly differentially expressed compared with the normal control. CONCLUSION: IL2Rß (Interleukin-2 receptor beta) is strongly associated with the onset and progression of autoimmune joint diseases, and may be used as a potential biomarker of AS. This study offers new characteristics that can help in the diagnosis and individualized therapy of AS.

Low­calorie sweetener D­psicose promotes hydrogen peroxide­mediated apoptosis in C2C12 myogenic cells favoring skeletal muscle cell injury.

Diet and exercise are the most effective approaches used to induce weight loss. D­psicose is a low­calorie sweetener that has been shown to reduce weight in obese individuals. However, the effect of D­psicose on muscle cells under oxidative stress, which is produced during exercise, requires further investigation. The present study aimed to determine the effects of D­psicose on C2C12 myogenic cells in vitro. Hydrogen peroxide (H2O2) was used to stimulate the generation of intracellular reactive oxygen species (ROS) in muscle cells to mimic exercise conditions. Cell viability was analyzed using a MTT assay and flow cytometry was used to analyze the levels of apoptosis, mitochondrial membrane potential (MMP), the generation of ROS and the cell cycle distribution following treatment. Furthermore, protein expression levels were analyzed using western blotting and cell proliferation was determined using a colony formation assay. The results of the present study revealed that D­psicose alone exerted no toxicity on C2C12 mouse myogenic cells. However, in the presence of low­dose (100 µM) H2O2­induced ROS, D­psicose induced C2C12 cell injury and significantly decreased C2C12 cell viability in a dose­dependent manner. In addition, the levels of apoptosis and the generation of ROS increased, while the MMP decreased. MAPK family molecules were also activated in a dose­dependent manner following treatment. Notably, the combined treatment induced G2/M phase arrest and reduced the proliferation of C2C12 cells. In conclusion, the findings of the present study suggested that D­psicose may induce toxic effects on muscle cells in a simulated exercise situation by increasing ROS levels, activating the MAPK signaling pathway and disrupting the MMP.

Which is the most effective one in knee osteoarthritis treatment from mesenchymal stem cells obtained from different sources?-A systematic review with conventional and network meta-analyses of randomized controlled trials.

BACKGROUND: Due to varying degrees of difficulty in obtaining different mesenchymal stem cells (MSCs), the distinct pain levels and treatment costs, and for providing concrete evidence for future clinical practice, a thorough comparison of all relevant MSCs remained critical. Hence, this study aimed to achieve this objective to compare the efficacy of MSCs obtained from different sources in clinical outcomes and cartilage repair of knee osteoarthritis (KOA). METHODS: The EmBase, PubMed and Cochrane Library databases were searched for eligible studies. Randomized controlled trials (RCTs) that compared MSCs from different sources with placebo or each other in KOA patients. Conventional meta-analysis and frequentist network meta-analysis (NMA) were conducted. The primary clinical outcome was pain relief. The frequentist NMA was conducted using Stata with the "network" command. RESULTS: Eight studies (seven trials) involving 203 KOA patients were included in this meta-analysis. The MSCs were considered superior over placebo for pain relief and improved function in KOA, but showed no statistically significant differences for cartilage regeneration. Among all the MSCs, the adipose tissue-derived MSCs (AD-MSCs) most effectively relieved pain. CONCLUSION: These findings suggested that MSCs are effective in the treating of KOA. AD-MSCs might be the most effective for relieving pain, and Umbilical cord-derived mesenchymal stem cells (UC-MSCs) might be the most effective for improving function. However, the current evidence does not support the use of MSCs for improving cartilage repair in KOA patients.

The molecular mechanism of a novel derivative of BTO-956 induced apoptosis in human myelomonocytic lymphoma cells.

Acute myeloid leukemia (AML) is a malignant cancer of the hematopoietic system. Although the effectiveness of arsenic compounds has been recognized and applied clinically, some patients are still found resistant to this chemotherapy. In this study, we investigated that a synthetic thyroid hormone analog (TA), 2-iodo-4-nitro-1-(o-tolyloxy) benzene, had a strong apoptosis effect on U937 cells. U937 cells were treated with TA, and examinted the generation of reactive oxygen species (ROS), dysfunction of mitochondria, expression of pro-apoptosis and anti-apoptosis, and cleavage of caspase-3 and Poly (ADP-ribose) polymerase (PARP). Further, it is also evaluated that insight molecular mechanism and signaling pathways involved in the study. It is found that TA significantly induced apoptosis in U937 cells through production of ROS, dysfunction of mitochondria, and activation of caspase cascade. It was also observed that MAPK signaling pathway including ERK, JNK, and P38 signals are involved in the induction of apoptosis. Moreover, marked activation of autophagy and ER stress markers such as LC3, P62, Beclin1 and GRP78, CHOP were observed, respectively. Pretreatment with ER stress inhibitor tauroursodeoxycholic acid (TUDCA) and autophagy inhibitor 3-Methyladenine (3-MA) have successfully attenuated and aggravated TA-induced apoptosis, respectively. We further confirmed the active involvement of ER stress and autophagy signals. In conclusion, TA induced apoptosis through ER stress and activation of autophagy, and the latter is not conducive to TA-induced cell death. Our results may provide a new insight into the strategic development of novel therapy for the treatment of AML.

Alpha-enolase (ENO1), identified as an antigen to monoclonal antibody 12C7, promotes the self-renewal and malignant phenotype of lung cancer stem cells by AMPK/mTOR pathway.

BACKGROUND: Tumor-associated antigens (TAAs) can be targeted in cancer therapy. We previously identified a monoclonal antibody (mAb) 12C7, which presented anti-tumor activity in lung cancer stem cells (LCSCs). Here, we aimed to identify the target antigen for 12C7 and confirm its role in LCSCs. METHODS: Immunofluorescence was used for antigen localization. After targeted antigen purification by electrophoresis and immunoblot, the antigen was identified by LC-MALDI-TOF/TOF mass spectrometry, immunofluorescence, and immunoprecipitation. The overexpression or silence of ENO1 was induced by lentiviral transduction. Self-renewal, growth, and invasion of LCSCs were evaluated by sphere formation, colony formation, and invasion assay, respectively. High-throughput transcriptome sequencing (RNA-seq) and bioinformatics analysis were performed to analyze downstream targets and pathways of targeted antigen. RESULTS: Targeted antigen showed a surface antigen expression pattern, and the 43-55 kDa protein band was identified as α-enolase (ENO1). Self-renewal, growth, and invasion abilities of LCSCs were remarkably inhibited by ENO1 downregulation, while enhanced by ENO1 upregulation. RNA-seq and bioinformatics analysis eventually screened 4 self-renewal-related and 6 invasion-related differentially expressed genes. GSEA analysis and qRT-PCR verified that ENO1 regulated self-renewal, invasion-related genes, and pathways. KEGG pathway analysis and immunoblot demonstrated that ENO1 inactivated AMPK pathway and activated mTOR pathway in LCSCs. CONCLUSIONS: ENO1 is identified as a targeted antigen of mAb 12C7 and plays a pivotal role in facilitating self-renewal, growth, and invasion of LCSCs. These findings provide a potent therapeutic target for the stem cell therapy for lung cancer and have potential to improve the anti-tumor activity of 12C7.

Preoperative imaging differences of patients with cervical spondylosis with cervical vertigo indicate the prognosis after cervical total disc replacement.

OBJECTIVE: To evaluate the relationship between the preoperative imaging differences and prognosis in patients with cervical spondylosis with cervical vertigo who underwent total disc replacement (TDR). METHODS: This was a retrospective study of patients with cervical spondylosis with cervical vertigo treated with single-segment TDR. The severity of pre- and postoperative cervical vertigo was evaluated separately. Paired samples t-tests were used to compare the severity of the symptoms before and after surgery. Characteristics of plain films, computed tomography myelography and magnetic resonance imaging were compared between patients with different outcomes by analysis of variance and Fisher's exact tests. RESULTS: The severity of cervical vertigo was significantly different after single-segment TDR. Three groups with different treatment outcomes were not significantly different with regard to gender, age, type of the cervical spondylosis, follow-up time, segment of surgery, cervical curve, range of motion, T2WI high signal in the spinal cord, and location of compression. The type of compression was significantly different between the three groups. CONCLUSIONS: Cervical vertigo was improved in patients with cervical spondylosis through the TDR procedure. Those in whom a herniated disc was the main source of compression may have a better prognosis following TDR.

Analgesic Efficacy of Adductor Canal Block in Total Knee Arthroplasty: A Meta-analysis and Systematic Review.

The aim of this meta-analysis and systematic review of randomized controlled trials (RCTs) was to evaluate the efficacy and safety of adductor canal block (ACB) for early postoperative pain management in patients undergoing total knee arthroplasty (TKA). Relevant manuscripts comparing ACB with saline or femoral nerve block (FNB) in TKA patients were searched for in the databases of PubMed, EMBASE, and Cochrane library. The outcomes assessed included cumulative analgesic consumption, pain at rest or during movement, ability to ambulate, quadriceps strength, and complications (nausea, vomiting or sedation). For continuous outcomes, pooled effects were measured using weighted mean difference (WMD) or standard mean difference (SMD), together with 95% confidence intervals (CIs). For outcomes without sufficient data for synthesis, qualitative interpretation of individual studies was summarized. Finally, 11 RCTs involving 675 patients met the inclusion criteria. The pooled results showed that ACB resulted in less postoperative analgesic consumption than saline (WMD, -12.84 mg; 95% CI, -19.40 mg to -6.27 mg; P < 0.001) and less pain at rest or during activity. No conclusions could be drawn regarding ability to ambulate and quadriceps strength, because only one study reported these variables. Most studies comparing ACB and FNB reported similar effects on postoperative analgesic consumption (WMD, -0.56 mg; 95% CI, -8.05 mg to 6.93 mg; P = 0.884) and pain; however, ability to ambulate and quadriceps strength were significantly better with ACB (SMD, 0.99; 95% CI, 0.04-1.94; P = 0.041). Additionally, ACB did not increase the rate of complications. Our results suggest that, compared with saline, ACB decreases analgesic consumption and offers short-term advantages in terms of pain relief. Compared with FNB, ACB was associated with better ability to ambulate and quadriceps strength.

Population-Stratified Analysis of Bone Mineral Density Distribution in Cervical and Lumbar Vertebrae of Chinese from Quantitative Computed Tomography.

OBJECTIVE: To investigate the bone mineral density (BMD) of cervical vertebrae in a population-stratified manner and correlate with that of the lumbar vertebrae. MATERIALS AND METHODS: Five hundred and ninety-eight healthy volunteers (254 males, 344 females), ranging from 20 to 64 years of age, were recruited for volumetric BMD (vBMD) measurements by quantitative computed tomography. Basic information (age, height, weight, waistline, and hipline), and vBMD of the cervical and lumbar vertebrae (C2-7 and L2-4) were recorded. Comparisons among sex, age groups and different levels of vertebrae were analyzed using analysis of variance. Linear regression was performed for relevance of different vertebral levels. RESULTS: The vBMD of cervical and lumbar vertebrae was higher in females than males in each age group. The vBMD of the cervical and lumbar vertebrae in males and the vBMD of lumbar vertebrae in females decreased with aging. In each age group, the vBMD of the cervical vertebrae was higher than that of the lumbar vertebrae with gradual decreases from C2 to C7 except for C3; moreover, the vBMD of C6 and C7 was significantly different from that of C2-5. Correlations of vBMD among different cervical vertebrae (females: r = 0.62-0.94; males: r = 0.63-0.94) and lumbar vertebrae (males: r = 0.93-0.98; females: r = 0.82-0.97) were statistically significant at each age group. CONCLUSION: The present study provided normative data of cervical vertebrae in an age- and sex-stratified manner. Sex differences in vBMD prominently vary with age, which can be helpful to design a more comprehensive pre-operative surgical plan.

Knockdown of asporin affects transforming growth factor-ß1-induced matrix synthesis in human intervertebral annulus cells.

BACKGROUND/OBJECTIVE: Asporin is associated with osteoarthritis and lumbar disk degeneration. Previous studies in chondrocytes showed that asporin can bind to transforming growth factor-ß1 (TGF-ß1) and downregulate matrix biosynthesis. However, this has not been studied in intervertebral disk (IVD) cells. This study aimed to inspect the expression of asporin under TGF-ß1 stimulation and its effect on TGF-ß1-induced matrix biosynthesis in human intervertebral annulus cells. METHODS: Human intervertebral annulus cells were obtained from the pathological region of IVD in eight patients. After primary culture and redifferentiation in alginate beads, cells were reseeded and treated with different concentrations (5 ng/mL, 10 ng/mL, and 15 ng/mL) of TGF-ß1 for up to 24 hours. Total RNA extracted from the cells and those with asporin knockdown were subjected to real-time polymerase chain reaction analysis to examine the expression of asporin and extracellular matrix genes. RESULTS: TGF-ß1 stimulation induces asporin transcription significantly in a dose- and time-dependent manner. Knockdown of endogenous asporin leads to the upregulated expression of collagen II alpha 1 and aggrecan. CONCLUSION: Our results have verified a functional feedback loop between TGF-ß1 and asporin in human intervertebral annulus cells indicating that TGF-ß1-induced annulus matrix biosynthesis can be significantly upregulated by knockdown of asporin. Therefore, asporin could be a potential new therapeutic target and inhibition of asporin could be adopted to enhance the anabolic effect of TGF-ß1 in human intervertebral annulus cells in degenerative IVD diseases.

An evaluation of the mechanism of ABCA7 on cellular lipid release in ABCA7-HEC293 cell.

BACKGROUND: ABCA7 is a member of the ABCA subfamily that shows a high degree of homology to ABCA1 and, like ABCA1, mediates cellular cholesterol and phospholipid release by apolipoproteins when transfected in vitro. However, expression of ABCA7 has been shown to be downregulated by increased cellular cholesterol while ABCA1 was upregulated. METHODS: The underlying mechanism for this effect was examined in ABCA1 or ABCA7-transfected HEC293. Lipid content in the medium and cells was determined by enzymatic assays. Gene expression was quantitated by real time PCR, and protein content was determined by Western blotting. RESULTS: While ABCA7 mRNA was decreased by 25-hydroxycholesterol treatment, ABCA1 was apparently increased. Treatment with the synthetic LXR agonist T0901317 (T09) upregulated ABCA1 expression and apoAI-mediated cellular lipid release in ABCA1-transfected HEC293 cells, but ABCA7 expression and cellular lipid release in ABCA7-transfected HEC293 cells showed no obvious changes. CONCLUSION: The ABCA7 gene is regulated by sterol in a direction opposite to that of ABCA1.

Calpain-mediated ABCA1 degradation: post-translational regulation of ABCA1 for HDL biogenesis.

Helical apolipoproteins remove cellular phospholipid and cholesterol to generate nascent HDL and this reaction is the major source of plasma HDL. ABCA1 is mandatory and rate-limiting for this reaction. Besides regulation of the gene expression by transcriptional factors including LXR, AP2 and SREBP, the ABCA1 activity is regulated post-translationally by calpain-mediated proteolytic degradation of ABCA1 protein that occurs in the early endosome after its endocytosis. When the HDL biogenesis reaction is ongoing as helical apolipoproteins interact with ABCA1, ABCA1 becomes resistant to calpain and is recycled to cell surface after endocytosis. Biogenesis of HDL is most likely to take place on cell surface. Clearance rate of ABCA1 by this mechanism is also retarded by various factors that interact with ABCA1, such as α1-syntrophin, LXRß and calmodulin. Physiological relevance of the retardation by these factors is not entirely clear. Pharmacological inhibition of the calpain-mediated ABCA1 degradation results in the increase of the ABCA1 activity and HDL biogenesis in vitro and in vivo, and potentially suppresses atherogenesis. This article is part of a Special Issue entitled Advances in High Density Lipoprotein Formation and Metabolism: A Tribute to John F. Oram (1945-2010).

Cordycepin prevents hyperlipidemia in hamsters fed a high-fat diet via activation of AMP-activated protein kinase.

Hyperlipidemia is a major risk factor for cardiovascular diseases. In this study, we investigated the potential effects of cordycepin (3'-deoxyadenosine), a bioactive component of the fungus Cordyceps militaris, on hyperlipidemia. We found that in male Syrian golden hamsters fed a high-fat diet (HFD), daily administration of cordycepin effectively reduced the accumulation of serum total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-c) and suppressed HFD-associated increases in relative retroperitoneal fat. It also increased the levels of phospho-AMP-activated protein kinase (AMPK) and phospho-acetyl-CoA carboxylase (phospho-ACC) in liver and retroperitoneal adipose tissues. In HepG2 cells, cordycepin stimulated robust concentration- and time-dependent AMPK activation that correlated with the activation of ACC and the suppression of lipid biosynthesis. However, pretreatment with compound C, a specific inhibitor of AMPK, substantially abolished the effects of cordycepin on AMPK activation and lipid biosynthesis inhibition. These results indicate that cordycepin prevents hyperlipidemia via activation of AMPK. Experiments on abnormal metabolic mice indicated that cordycepin can also improve insulin sensitivity effectively.

[Shotgun proteomic analysis of intervertebral disc tissues from fetal and adult subjects].

OBJECTIVE: To acquire information on the IVD (intervertebral disc) proteome and analyze the differences of identified proteins during IVD development and maturation by a shotgun proteomics approach so as to identify the global protein expression patterns of IVD tissues from fetus and adults. METHODS: A 24-week fetus, a 25- and a 30-year-old adult IVD samples were collected and SDS-PAGE, RP-HPLC MS/MS shotgun analyses were performed. Bioinformational analysis with International Protein Index (IPI) database and functional classification with Gene Ontology Annotation (GOA) database were used to evaluate the results. RESULTS: A total of 524 proteins were identified in fetal IVD sample while 181 and 172 proteins were observed in 25 and 30-year-old samples respectively. Forty-eight proteins existed in three samples while 84 proteins in the 25-years-old and 30-years-old samples but not in fetus. Only 174 high-quality proteins existed in fetal sample while 20 high-quality proteins in 25-year-old and 30-year-old samples. The physico-chemical characteristics of identified proteins displayed similar trends in three samples. CONCLUSIONS: This study represents the first presentation of a global proteomic map of fetal and adult IVD samples using shotgun technology. Substantial differences exist in number and variety of proteins between development and mature IVD. This contributes to our overall knowledge in of biochemical components, metabolic regulation and biological mechanics in IVD.

[Relationship between 666C > T polymorphism of TIMP-1 and lumbar intervertebral disc degeneration].

OBJECTIVE: To detect the single nucleotide polymorphisms (SNPs) in exon 6 of tissue inhibitor of metalloproteinase-1 (TIMP-1) in young men in North China and to investigate the relationship between these polymorphisms and lumbar intervertebral disc degeneration. METHODS: The recruited subjects aged from 18 to 40 years old were divided by MRI into degeneration group (n = 48) and non-degeneration group (n = 49). The genomic DNA was collected from blood. After PCR amplification, the SNPs of TIMP-1 exon 6 were detected by DNA sequencing. RESULTS: Only the TIMP-1 666C > T (rs11551797) polymorphism was observed and the genotype was of homozygote (CC/TT). The difference between two group was statistically significant (χ(2) = 4.571, P = 0.033). Although the polymorphism was a synonymous mutation, the TT genotype mutant type was one of the risk factors for lumbar intervertebral disc degeneration (OR = 3.269, 95%CI 1.063 - 10.047). In the degeneration group, no significant correlation was found between the polymorphism, extent, level and number of degenerated intervertebral discs. CONCLUSION: TIMP-1 666C > T polymorphism present in north Chinese young men may lead to lumbar intervertebral disc degeneration. However it has no effect on the degree, level and number of degenerated intervertebral discs.