To investigate the mechanism by which Cangxi Tongbi Capsules promote chondrocyte autophagy to inhibit knee osteoarthritis(KOA) progression by regulating the circRNA＿0008365/miR-1271/p38 mitogen-activated protein kinase(MAPK) pathway. The cell and animal models of KOA were established and intervened with Cangxi Tongbi Capsules, si-circRNA＿0008365, si-NC, and Cangxi Tongbi Capsules combined with si-circRNA＿0008365. Flow cytometry and transmission electron microscopy were employed to determine the level of apoptosis and observe autophagosomes, respectively. Western blot was employed to reveal the changes in the protein levels of microtubule-associated protein light chain 3(LC3)Ⅱ/Ⅰ, Beclin-1, selective autophagy junction protein p62/sequestosome 1, collagen Ⅱ, a disintegrin and metalloproteinase with thrombospondin motifs 5(ADAMTS-5), and p38 MAPK. The mRNA levels of circRNA＿0008365, miR-1271, collagen Ⅱ, and ADAMTS-5 were determined by qRT-PCR. Hematoxylin-eosin staining was employed to reveal the pathological changes of the cartilage tissue of the knee, and enzyme-linked immunosorbent assay to measure the levels of interleukin-1β(IL-1β) and tumor necrosis factor-alpha(TNF-α). The chondrocytes treated with IL-1β showed down-regulated expression of circRNA＿0008365, up-regulated expression of miR-1271 and p38 MAPK, lowered autophagy level, increased apoptosis rate, and accelerated catabolism of extracellular matrix. The intervention with Cangxi Tongbi Capsules up-regulated the expression of circRNA＿0008365, down-regulated the expression of miR-1271 and p38 MAPK, increased the autophagy level, decreased the apoptosis rate, and weakened the catabolism of extracellular matrix. However, the effect of Cangxi Tongbi Capsules was suppressed after interfering with circRNA＿0008365. The in vivo experiments showed that Cangxi Tongbi Capsules dose-dependently inhibited the p38 MAPK pathway, enhanced chondrocyte autophagy, and mitigated articular cartilage damage and inflammatory response, thereby inhibiting the progression of KOA in rats. This study indicated that Cangxi Tongbi Capsules promoted chondrocyte autophagy by regulating the circRNA＿0008365/miR-1271/p38 MAPK pathway to inhibit the development of KOA.
Rats ; Animals ; Chondrocytes ; Osteoarthritis, Knee/pathology* ; RNA, Circular/pharmacology* ; p38 Mitogen-Activated Protein Kinases/metabolism* ; MicroRNAs/metabolism* ; Apoptosis ; Autophagy/genetics* ; Collagen/metabolism*

OBJECTIVE: To investigate the enhancement of macrophage chemotaxis in patients with knee osteoarthritis (KOA) and its correlation with the disease severity. METHODS: Eighty patients with KOA admitted from July 2019 to June 2022 were enrolled as the observation group and divided into 29 cases of moderate group, 30 cases of severe group and 21 cases of extremely severe group. At the same time, 30 healthy subjects were included as the control group. The gene expressions of NF-κB, CXC chemokine receptor 7 (CXCR7) and CXC chemokine ligand 12 (CXCL12) in macrophages of each group were analyzed. Visual analogue scale(VAS) was used to evaluate the degree of joint pain. Joint function was evaluated by knee Joint Society Scoring system(KSS). Finally, data analysis was carried out. RESULTS: The expression levels of NF-κB, CXCR7 and CXCL12 in moderate group, severe group and extreme recombination group were higher than those in control group. The VAS, the expression of NF-κB, CXCR7 and CXCL12 in the severe group and the extreme recombination group were higher than those in the moderate group, whereas KSS was lower than that in the moderate group. The VAS, expression levels of NF-κB, CXCR7 and CXCL12 in the extremely severe group were higher than those in the severe group, and KSS was lower than that in the severe group (all P<0.01). The expression levels of NF-κB, CXCR7 and CXCL12 in macrophages were positively correlated with VAS score, but negatively correlated with KSS(all P<0.01). The expression levels of NF-κB, CXCR7 and CXCL12 in macrophages were positively correlated with the severity of disease. After excluding the influence of traditional factors (gender, age and disease duration), multiple linear regression analysis further showed that the expression levels of NF-κB, CXCR7 and CXCL12 were still positively correlated with the severity of disease(all P<0.01). CONCLUSION The chemotaxis of macrophages in patients with KOA increased with the aggravation of the disease, and was related to the degree of pain and function impairment.
Humans ; Osteoarthritis, Knee/genetics* ; Chemotaxis/genetics* ; NF-kappa B/metabolism* ; Macrophages/metabolism* ; Receptors, CXCR/metabolism* ; Patient Acuity

OBJECTIVE: To observe the effect of needle-knife on the chondrocyte apoptosis of knee joint in rabbits with knee osteoarthritis (KOA) based on the CircSERPINE2-miR-1271-5P-E26 specific transformation-related gene (ERG) axis, and to explore the mechanism of needle-knife for KOA. METHODS: Thirty-six New Zealand white rabbits were randomly divided into a normal group, a model group, a needle-knife group and a sham needle-knife group, 9 rabbits in each group. The rabbits in the model group, the needle-knife group and the sham needle-knife group were treated with modified Videman method to prepare KOA model. After successful modeling, the rabbits in the needle-knife group were treated with needle-knife at cord adhesion and nodules near quadriceps femoris tendon and internal and external collateral ligament on the affected knee joint; the rabbits in the sham needle-knife group were treated with sham needle-knife baside the needle insertion point of the needle-knife group (needle-knife was only inserted, without any operation). The treatment was given once a week, 3 times in total. The Lequesne MG behavioral score was used to evaluate the knee joint damage in each group before and after intervention. After intervention, HE staining and transmission electron microscopy were used to observe the cartilage tissue morphology and ultrastructure of chondrocytes in the knee joint in each group; TUNEL method was used to detect the level of chondrocyte apoptosis in the knee joint; real-time fluorescence quantitative PCR was used to detect the expression of CircSERPINE2, miR-1271-5P and ERG mRNA in knee cartilage tissue in each group. RESULTS: After intervention, compared with the normal group, the Lequesne MG behavioral score in the model group was increased (P<0.01). Compared with the model group and the sham needle-knife group, the Lequesne MG behavioral score in the needle-knife group was decreased (P<0.01). In the model group and the sham needle-knife group, the number of chondrocytes and organelles was decreased, the cell nucleus was shrunk, mitochondria was swelling or disappeared; in the needle-knife group, the number of chondrocytes and organelles was increased, the cell nucleus was not obviously shrunk and the mitochondria was not obviously swelling. Compared with the normal group, the level of chondrocyte apoptosis in the model group was increased (P<0.01); compared with the model group and the sham needle-knife group, the level of chondrocyte apoptosis in the needle-knife group was decreased (P<0.01, P<0.05). Compared with the normal group, the expression of CircSERPINE2 and ERG mRNA in the model group was decreased (P<0.01), and the expression of miR-1271-5P mRNA was increased (P<0.01); compared with the model group and the sham needle-knife group, the expression of CircSERPINE2 and ERG mRNA in the needle-knife group was increased (P<0.01), and the expression of miR-1271-5P mRNA was decreased (P<0.01). CONCLUSION Needle-knife could reduce the knee joint damage and chondrocyte apoptosis in KOA rabbits, which may be related to up-regulating the expression of CircSERPINE2 and ERG mRNA, and inhibiting the expression of miR-1271-5P mRNA.
Rabbits ; Animals ; Osteoarthritis, Knee/metabolism* ; Chondrocytes/metabolism* ; Knee Joint/surgery* ; Apoptosis ; MicroRNAs/genetics*

Objective: To investigate the repair effect and JNK/NF-κB,SOX9 mechanisms of vibration exercise with different frequencies on articular cartilage in rats with early knee osteoarthritis. Methods: Forty-eight adult male SD rats were randomly divided into six groups(n=8):model control group(MC),high frequency vibration group 1 (GP₁,60 Hz),high frequency vibration 2 group (GP₂,40 Hz),medium frequency vibration group (ZP,20 Hz),minor frequency group(DP,10 Hz)and normal control group(NC). Except for NC group,the rats in each group were made into early knee osteoarthritis model after six weeks of knee joint cavity injection of papain solution and 2% mixture l-cysteine on the 1^st,4 ^th and 7^th day. Each exercise group was subjected vibration to 40 minutes a day with amplitude of 2～5 mm and 5 days a week. Four weeks later, the articular cartilage of the lateral femoral condyle of the both back leg knee joints were detected by HE staining,serine O staining and Mankin scores for morphological observation. The expression levels of JNK,NF-κB p65 and Sox9 mRNA in articular cartilage of the medial femoral condyle were detected by RT-qPCR,and the protein expressions of JNK,NF-κB p65 and Sox9 were detected by Western blot. Results: Compared with the NC group,the Mankin score in other groups was significantly higher (P＜0.01). Compared with the MC group,the Mankin score of each vibration group was significantly lower(P＜0.05),the mRNA and protein expressions of JNK and NF-κB p65 in each vibration training group were significantly lower (P＜0.01),the expressions of Sox9 mRNA and protein in vibration training group were increased significantly (P＜0.01). Compared with the higher frequency group,the Mankin score,the mRNA and protein expressions of JNK and NF-κB p65 of lower frequency group were significantly lower (P＜0.05 or P＜0.01). But the expressions of Sox9 mRNA and protein were significantly higher (P＜ 0.05 or P＜0.01). Conclusion: Vibration exercise of different frequencies may present varying degrees of cartilage repair impact in rats with early knee osteoarthritis,and the cartilage repair by low-frequency vibration training is better than that by high-frequency vibration. This can be one of the mechanisms on controlling collagen synthesis by down-regulating JNK/NF-κB expression and increasing SOX9 activity of OA articular cartilage.
Animals ; Cartilage, Articular/metabolism* ; MAP Kinase Kinase 4 ; Male ; NF-kappa B/metabolism* ; Osteoarthritis, Knee/therapy* ; RNA, Messenger/metabolism* ; Rats ; Rats, Sprague-Dawley ; SOX9 Transcription Factor ; Vibration

Osteoarthritis (OA) is a degenerative articular disorder manifested by cartilage destruction, subchondral sclerosis, osteophytes, and synovitis, resulting in chronic joint pain and physical disability in the elderly. The purpose of this study was to investigate mitochondrial DNA copy number (mtDNA_CN) and inflammatory cytokines in primary knee OA patients and healthy volunteers. A total of 204 knee OA patients and 169 age-matched healthy volunteers were recruited. Their relative blood leukocyte mtDNA_CN was assessed by quantitative real-time polymerase chain reaction (qRT-PCR), and ten inflammatory cytokines in their plasma were detected by multiplex immunoassay. Blood leukocyte mtDNA_CN in the OA group was significantly lower than that in the control group. Leukocyte mtDNA_CN in the control group was negatively correlated with their age (r=-0.380, P<0.0001), whereas mtDNA_CN in the OA group was positively correlated with their age (r=0.198, P<0.001). Plasma interleukin-4 (IL-4) and IL-6 were significantly higher in the knee OA group than in the control group. The plasma IL-6 level was positively correlated with blood leukocyte mtDNA_CN in the OA group (r=0.547, P=0.0014). IL-5 showed as a major factor (coefficient 0.69) in the second dimension of principle components analysis (PCA)-transformed data and was significantly higher in the OA group (P<0.001) as well as negatively correlated with mtDNA_CN (r=-0.577, P<0.001). These findings suggest that elevation of plasma IL-4 and IL-6 and a relative reduction in mtDNA_CN might be effective biomarkers for knee OA. IL-5 is a plausible factor responsible for decreasing blood leukocyte mtDNA_CN in knee OA patients.
Age Factors ; Aged ; Aged, 80 and over ; Cytokines/blood* ; DNA, Mitochondrial/blood* ; Female ; Gene Dosage ; Humans ; Leukocytes/metabolism* ; Male ; Middle Aged ; Osteoarthritis, Knee/metabolism* ; Principal Component Analysis

OBJECTIVE: To investigate the changes in the expression of voltage-gated potassium channel subunit KCNA2 in the dorsal root ganglion (DRG) neurons of rats with osteoarthritis (OA) pain induced by sodium monoiodoacetate and explore the mechanism. METHODS: A total of 156 adult male Sprague-Dawley rats were randomly divided into blank control group, saline group and intra-articular monoiodoacetate injection-induced OA group. The paw withdrawal mechanical threshold (PWMT) was measured before and at 1, 2, 4, and 6 weeks after monoiodoacetate injection. At 4 weeks after the injection, the pathological changes in the knee joints were analyzed using HE staining and Safranin O-Fast Green staining, and the expression of activating transcription factor 3 (ATF-3) and inducible nitric oxide synthase (iNOS) in the DRG neurons were detected by immunofluorescence staining. The expression of mRNA in the DRG neurons was detected by RT-qPCR at 1, 2, 4 and 6 weeks after the injection. The expression of KCNA2 in the DRG was measured by Western blotting, and the methylation level of promoter region was measured by MSPCR at 4 weeks after the injection. RESULTS: The PWMT of the rats in OA group was significantly decreased at 2, 4, and 6 weeks after the injection as compared with the baseline ( < 0.05 or < 0.001) as well as the control group ( < 0.05 or < 0.001). Four weeks after the intra-articular injection, fractures and defects on the surface of the articular cartilage, bone hyperplasia, and blurred tidal line were observed in the rats in OA group, but no obvious pathological changes were detected in the control or saline groups. Compared with those in the control group, the expressions of ATF-3 and iNOS were significantly increased ( < 0.01) at 4 weeks after injection; the expression of mRNA at 2, 4 and 6 weeks and the expression of KCNA2 protein at 4 weeks were all significantly decreased ( < 0.05 or < 0.01), and the methylation level of gene was significantly increased at 4 weeks after the injection in OA group ( < 0.01). CONCLUSIONS The expression of KCNA2 is decreased in the DRG neurons of rats with OA pain likely as a result of enhanced methylation of promoter region.
Animals ; Disease Models, Animal ; Ganglia, Spinal ; Knee Joint ; Kv1.2 Potassium Channel ; metabolism ; Male ; Osteoarthritis ; complications ; metabolism ; Pain ; etiology ; metabolism ; Promoter Regions, Genetic ; Rats ; Rats, Sprague-Dawley

OBJECTIVE: To explore the action mechanism of electroacupuncture (EA) for knee osteoarthritis (KOA) based on Wnt/beta-catenin (Wnt/β-catenin) signaling pathway. METHODS: Ten rats were randomly selected into a sham-operation group among 50 male 2-month-old SD rats, and the KOA model was established in the remaining 40 rats by modified Hulth method. Four weeks after the model establishment, the rats were randomly divided into a model group, an experimental A group, an experimental B group and an experimental C group, 10 rats in each group. The rats in the sham-operation group and model group did not receive any intervention. The rats in the experimental A group were treated with EA at "Neixiyan" (EX-LE 4) and "Dubi"(ST 35) for 15 min. The rats in the experimental B group were treated with EA at "Neixiyan" (EX-LE 4) and "Dubi"(ST 35) for 30 min. The rats in the experimental C group were treated with EA at non-acupoint for 15 min. EA intervention was given once a day, five times a week, and totally 12-week treatment was given. After 12 weeks, the knee cartilage tissues were stained and the morphological changes were observed under light microscopy; the severity of cartilage degeneration was evaluated by modified Mankin's score; the content of interleukin-1β (IL-1β) in synovium tissues was detected by ELISA method; the content of Wnt-4, β-catenin and matrix metalloprotein-13 (MMP-13) in cartilage tissues was detected by Western blot method. RESULTS: Compared with the sham-operation group, in the model group the morphology and structure of cartilage were disordered, the number of cells was significantly reduced, the matrix was decontaminated and tidal line was incomplete; the Mankin's score was significantly increased (<0.01), the content of IL-1β in synovium tissues were significantly increased (<0.01), and the expressions of Wnt-4, β-catenin and MMP-13 at protein level were significantly increased (<0.01). Compared with the model group, in the experimental A group and experimental B group the morphology and structure of cartilage were more orderly, the number of cells was increased, the matrix staining was deepened and the tidal line was more complete; Mankin's scores were decreased significantly (<0.01); the contents of IL-1β in synovium tissues were decreased significantly (<0.01), and the expressions of Wnt-4, β-catenin and MMP-13 at protein level were decreased significantly (<0.01). Compared with the model group, no improvement was observed in the experimental C group. Compared with the experimental A group, in the experimental C group the morphology and structure of cartilage were disordered, the number of cells was significantly reduced, the matrix was decontaminated and the tidal line was incomplete; Mankin's score was significantly increased (<0.01), the content of IL-1β in synovium tissues was significantly increased (<0.01), and the expressions of Wnt-4, β-catenin and MMP-13 at protein level were significantly increased (<0.01). The morphological structure of cartilage in the experimental B group was similar to that in the experimental A group, and there was no significant difference in Mankin's score, IL-1β content in synovium tissues and the expressions of Wnt-4, β- catenin and MMP-13 at protein level between the two groups (>0.05). CONCLUSION EA at "Neixiyan" (EX-LE 4) and "Dubi"(ST 35) may reduce the expression of MMP-13 and the production of inflammatory factor IL-1β through Wnt/β-catenin signaling pathway, thus inhibit the degradation of cartilage matrix and the apoptosis of chondrocyte, and improve the morphology and structure of cartilage.
Animals ; Cartilage, Articular ; metabolism ; Electroacupuncture ; Humans ; Male ; Osteoarthritis, Knee ; therapy ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; Wnt Signaling Pathway

OBJECTIVETo observe the impacts of thermosensitive moxibustion (TSM) on the expressions of nitric oxide (NO), typeⅠdisintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS-4), typeⅡcollagen and proteoglycan (PG) in the rabbit models of knee osteoarthritis (KOA) and explore the mechanism of TSM on KOA.

METHODSA total of 42 Japanese long-eared male rabbits were divided into a blank group (6 rabbits), a model group (6 rabbits), a moxibustion group (24 rabbits) and a sham-operation group (6 rabbits) according to the random number table. In the blank group, the rabbits were fed normally. In the model and moxibustion groups, the papain injection was given to establish KOA models. The rabbits in the sham-operation group were treated with the intracavity injection of 0.9% NaCl solution. The rabbits were forced to move for 30 min every day, continuously for 15 days during modeling. At the end of modeling, in the moxibustion group, moxibusiton was applied at "Dubi" (ST 35), once a day, 40 min each time, for 14 days totally. According to the temperature changes during moxibustion, the rabbits were divided into a TSM group and a non-TSM group. 6 rabbits were collected randomly from the two groups. The usual feeding was given in the blank group, the model group and the sham-operation group, without any intervention. The body mass and behavioristics changes were observed in each group. At the end of treatment, the nitrate reduction method was adopted to determine NO expression in the serum. The real-time PCR was adopted to determine the expressions of ADAMTS-4, typeⅡcollagen and PG in the cartilage.

RESULTS① After modeling, compared with the blank group, the body mass was all reduced and the Lequesne MG score was increased in the model group, TSM group, non-TSM group and sham-operation group (<0.05, <0.01). After intervention, compared with the blank group, the body mass was decreased and the Lequesne MG score was increased in the model and sham-operation groups (<0.05, <0.01). Compared with the model group, the body mass was increased and the lequesne MG score was decreased in the TSM, non-TSM, and sham-operation groups (<0.05, <0.01). Compared with the non-TSM group, the body mass in the TSM group was increased remarkably (<0.05), but the difference in Lequesne MG score was not statistically significant (>0.05). ② After intervention, compared with the blank group, the expressions of NO and ADAMTS-4 were all increased and the expressions of typeⅡcollagen and PG were decreased in the model group, TSM group, non-TSM group and sham-operation group (<0.05, <0.01). Compared with the model group, the expressions of NO and ADAMTS-4 were all remarkably lower and the expressions of typeⅡcollagen and PG were increased in the TSM group, non-TSM group and sham-operation group (<0.05, <0.01). Compared with the non-TSM group, the expressions of NO and ADAMTS-4 were all remarkably lower and the expressions of typeⅡcollagen and PG were increased in the TSM group after intervention (all <0.05).

CONCLUSIONThe thermosensitive moxibustion alleviates the inflammatory reactions and protects the joint cartilage through inhibiting the expressions of NO and ADAMTS-4 to achieve the effects in the treatment of KOA.

ADAMTS4 Protein ; metabolism ; Animals ; Cartilage ; metabolism ; Collagen Type III ; metabolism ; Male ; Moxibustion ; Nitric Oxide ; blood ; Osteoarthritis, Knee ; therapy ; Proteoglycans ; metabolism ; Rabbits ; Random Allocation

OBJECTIVES: To observe the effects of Yougui pill (Traditional Chinese Medicine) on the related factors of Wnt signal pathway of rats with knee osteoarthritis (KOA), and explore its protective mechanism. METHODS: Sixty SPF SD rats were randomly divided into the sham-operative group, model group, glucosamine sulfate group, high-dose, middle-dose, low-dose of Yougui pill treated group (=10). KOA model was established by modified Hulth method for six weeks. The rats in the high, middle and low-dose of Yougui pill group were treated with Yougui pills at the doses of 20,10 and 5 g/kg respectively by gastrogavage once a day for 8 weeks, while equal volume of normal saline was given to those in the sham and model control group and an equal volume of glucosamine sulfate (1.7 g/kg·d) was given to those in glucosamine sulfate group for 8 weeks. The knee joint was removed after the last dose of drug. The pathological changes of cartilaginous tissues were observed under a microscope. The mRNA levels of Dickkopf homolog 1(DKK1), Wnt induced secreted protein 1(WISP1), Wnt1, low density lipoprotein receptor related protein 5(LRP5) and beta -catenin in rats cartilaginous tissues were analyzed by using RT-PCR method, and the protein contents of DKK1, WISP1, Wnt1, LRP5 and beta-catenin in cartilaginous tissues were detected by Western blot. RESULTS: Compared with the sham group, the articular cartilage was severely damaged, the Mankin score was increased significantly (<0. 05), the mRNA and protein expression levels of DKK1 in cartilaginous tissue were markedly decreased(<0.05), while those of WISP, Wnt1, LRP5 and beta-catenin were increased significantly in model group(<0.05). Compared with model group, the articular cartilage lesions was light (<0.05), the Mankin Score was decreased significantly(<0.05), and the mRNA and protein levels of DKK1 in cartilaginous tissue were increased(<0.05), while those of WISP, Wnt1, LRP5 and beta-catenin were decreased in Yougui pill high-dose group and glucosamine sulfate group (<0.05). CONCLUSIONS Yougui pill has protective effects on the KOA by inhibiting the expressions of WISP, Wnt1, LRP5, beta-catenin and increasing the expression of DKK1 cytokine in the Wnt signaling pathway.
Animals ; CCN Intercellular Signaling Proteins ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Glucosamine ; pharmacology ; Intercellular Signaling Peptides and Proteins ; metabolism ; Osteoarthritis, Knee ; drug therapy ; Proto-Oncogene Proteins ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Wnt Signaling Pathway ; Wnt1 Protein ; metabolism ; beta Catenin ; metabolism

PURPOSE: The aim of this study was to determine the relationship of hypoxia-inducible factor-2 (HIF-2α) and vascular endothelial growth factor (VEGF) with radiographic severity in primary osteoarthritis (OA) of the knee. Expression of these two factors in cartilage samples from OA knee joints was examined at mRNA and protein levels. MATERIALS AND METHODS: Knee joints were examined using plain radiographs, and OA severity was assessed using the Kellgren and Lawrence (KL) grading system. Specimens were collected from 29 patients (31 knees) who underwent total knee replacement because of severe medial OA of the knee (KL grades 3 and 4), 16 patients who underwent knee arthroscopy (KL grade 2), and 5 patients with traumatic knees (KL grade 0). HIF-2α and VEGF expression was quantified by real-time polymerase chain reaction and western blotting. RESULTS: Cartilage degeneration correlated with the radiographic severity grade. OA severity, determined using the Mankin scale, correlated positively with the KL grade (r=0.8790, p<0.01), and HIF-2α and VEGF levels with the radiographic severity of knee OA (r=0.7001, p<0.05; r=0.6647, p<0.05). CONCLUSION: In OA cartilage, HIF-2α and VEGF mRNA and protein levels were significantly and positively correlated. The expression of both factors correlated positively with the KL grade. HIF-2α and VEGF, therefore, may serve as biochemical markers as well as potential therapeutic targets in knee OA.
Adult ; Aged ; Arthroplasty, Replacement, Knee ; Arthroscopy ; Basic Helix-Loop-Helix Transcription Factors/*metabolism ; Biomarkers/*blood ; Cartilage/*metabolism ; Female ; Humans ; Knee Joint/*diagnostic imaging ; Male ; Middle Aged ; Osteoarthritis, Knee/*blood/diagnostic imaging/physiopathology ; RNA, Messenger ; Radiography ; Real-Time Polymerase Chain Reaction ; Severity of Illness Index ; Vascular Endothelial Growth Factor A/*metabolism