Alleviation of Papain-Induced Osteoarthritis by Recombinant Human Endostatin via Downregulation of Matrix Metalloproteinase-13, Interleukin-1 and Interleukin-6 in Rats

Osteoarthritis (OA) is a degenerative disease of joints commonly occurring in the elderly and middleaged people. This study aimed to investigate the effect of recombinant human endostatin (rhEndo) on OA and the levels of MMP-13, IL-1 and IL-6 in the synovial fluid in osteoarthritis rats. OA models were made by injecting 4% papain into the knee joint cavity of rats once every three days for three times. The models were then injected subcutaneously with rhEndo and examined six weeks later for the Mankin scores and levels of MMP-13, IL-1 and IL-6 using ELISA. Compared with control, the Mankin score as well as the levels of IL-1, IL-6 and MMP-13 were significantly increased in the models (0.30 vs. 5.80, 1.12 vs. 12.84 pg/ mL, 12.22 vs. 43.82 pg/ mL and 0.23 vs. 26.31 ng/ mL). Following treatment with 4 mg/kg rhEndo, the Mankin score in model decreased to 0.90, meanwhile, the levels of IL-1, IL-6 and MMP-13 decreased significantly to 0.79 pg/ mL, 2.89 pg/mL and 1.17 ng/mL, respectively, in a dose dependent manner. Therefore, rhEndo can alleviate osteoarthritis by reducing MMP-13, IL-1 and IL-6 expression in rats.

Effect of Nerve Training Technology on Apoptosis of Cartilage and Osteoblasts and Expression of Aggrecan Protein in Osteoporotic Arthritis

Arthritis and osteoporosis are two common disorders in the world, especially for the elder, but the current treatments have limited efficacy. Herein, we aimed to determine whether the novel technique, neurological training can alleviate osteoporosis complicated with arthritis in rat model. Thirty rats were assigned into normal group, model group, and treatment group (treated with forsythin and neurological training) (n = 10) followed by assessment of chondrocytes and osteoblasts using Mankin score, apoptosis by TUNEL and flow cytometry, and IL-1β, TNF-α, and Aggrecan levels. Apoptotic chondrocytes of treatment group (27.43±1.34) was lower than model group (p < 0.05), whereas amount of osteoblast was increased upon forsythin and neurological training, with lower Mankin’s score (6.38±0.76). Besides, the content of IL-1β and TNF-α of treatment group was significantly lower but Aggrecan mRNA and protein expression was significantly higher. In conclusion, neurological training could protect and alleviate osteoporosis complicated with arthritis.

Comparison of properties determined using electromechanical assessment (Arthro-BST™) with macroscopic and histological properties in symptomatic human articular cartilage of the hip

Background Cartilage degeneration is assessed using various methods. Although macroscopic evaluation can directly measure cartilage degeneration, it cannot accurately assess cartilage properties. Histological examination is one of the most accurate methods for evaluating cartilage degeneration. However, it is invasive and requires collection of cartilage tissue. In contrast, the Arthro-BST™ probe can assess cartilage properties noninvasively. This study aimed to evaluate the effectiveness of the Arthro-BST in assessing cartilage degeneration by comparing macroscopic (International Cartilage Repair Society [ICRS] classification) and histological evaluations (modified Mankin score and Osteoarthritis Research Society International [OARSI] histological grade). Methods Fourteen femoral heads were excised from 13 patients during surgery to treat hip osteoarthritis or femoral fracture. The ICRS score was used for macroscopic evaluation of cartilage degeneration. The Arthro-BST was applied at sites matching the areas of cartilage damage. The sites assessed using the ICRS classification and Arthro-BST were evaluated histologically (modified Mankin score and OARSI histological grade), and these were compared with the Arthro-BST results. Results The ICRS classification identified significant differences between grades 1 and 3 (p < 0.01), between grades 1 and 4 (p < 0.01), between grades 2 and 3 (p < 0.01), and between grades 2 and 4 (p < 0.01). Significant correlations were observed between the Arthro-BST results and the ICRS score, modified Mankin score (structure, cellularity, matrix staining, total score), and OARSI histological grade. Conclusions In the assessment of hip osteoarthritis, the Arthro-BST results correlated with those of macroscopic and histological evaluations. The Arthro-BST is useful for assessing hip osteoarthritis and may be helpful for noninvasive assessment of cartilage degeneration.

Ligustrazine Reduces the Apoptosis of Synovial Cells in Knee Arthritis Rats by Inhibiting the Expression of Glucose Regulatory Protein 78 and CCAAT Enhancer Binding Protein Beta (C/EBPb)

To investigate the effect of Ligustrazine on synovial cells and expression of GRP78 and C/EBPb in knee arthritis rats, 52 healthy SD rats, aged 10-15 months, weighing 185–225 g, were selected and fed routinely. According to the principle of random distribution, the experimental rats were assigned into healthy group, arthritis group, ligustrazine 1 and 2 groups, with 13 rats in each group. HE staining was used to detect the pathological morphology. Mankin score was used to measure the severity of the disease. The apoptosis of synovial cells was assessed by flow cytometry. col2α1 and VEGF levels were detected by RT-PCR and GRP78, XBP1 and C/EBP β levels were detected by Western blot. In the healthy group, the cells were scattered orderly, the cartilage surface was smooth, and the synovial tissue was not damaged; in the arthritis group, the joint tissue was damaged, the synovial tissue proliferated and degenerated, the cells were disordered, and synovial pannus was produced; in Ligustrazine group 1 and Ligustrazine 2 groups had certain improvement, and the effect to Ligustrazine group 2 was more obvious. Mankin score of healthy group was lower than arthritis group (P < 0.05) which had higher Mankin score than Ligustrazine 1 and 2 groups, and the Mankin score of Ligustrazine 2 group was lower than that of Ligustrazine 1 group (P < 0.05). Synovial cells apoptosis in healthy group was lower than arthritis group (P < 0.05) which had higher apoptosis than Ligustrazine 1 group and ligustrazine 2 group (P < 0.05) with lower apoptosis for Ligustrazine 2 group (P < 0.05). The expressions of col2α1 mRNA and VEGF mRNA in healthy group were lower than arthritis group (P < 0.05) which had higher levels than Ligustrazine 1 and 2 groups with Ligustrazine 2 group showing more obvious effects (P < 0.05). Arthritis group had significantly elevated levels of GRP78 and XBP1 and decreased C/EBP β levels (P < 0.05). However, GRP78 and XBP1 levels in TMP-1 group and tmp-2 group were decreased and C/EBP β level was increased (P < 0.05). In a word, Ligustrazine can reduce the apoptosis of synovial cells, promote the repair of cartilage tissue and improve the condition of knee arthritis rats by regulating the expression level of GRP78 and XBP1.

Alendronate Regulates Knee Arthritis by Extracellular-Signal-Regulated Kinase (ERK) Pathway in Rat Model

The incidence of knee arthritis is high and treatment effect is not satisfactory. Alendronate (ALN) can treat metabolic bone diseases. But its role and mechanism in knee arthritis remains unclear. SD rats were randomly assigned into control group; model group; and alendronate group followed by analysis of the pathological changes by HE staining and Masson staining, bone mineral density by dual energy bone densitometry, expression of glycosaminoglycan and MMP-3 by immunohistochemistry, BMP-2 and BMP-4 expression by Real time PCR, IL-1β, IL-6 secretion by ELISA as well as ERK signaling protein level by Western blot. In model group, the pathological changes of joint inflammation were obvious with fibrosis on the cartilage surface, significantly increased synovial hyperplasia score, inflammatory infiltration score and Mankin score, decreased bone density, expression of glycosaminoglycan, MMP-3, BMP-2 and BMP-4 as well as increased IL-1β, IL-6 secretion and ERK1/2 expression (P <0.05). Alendronate treatment can significantly improve joint inflammation, reduce inflammatory infiltration score and Mankin score, increase bone density, expression of glycosaminoglycan, MMP-3, BMP-2 and BMP-4, decrease the secretion of IL-1β, IL-6 and expression of ERK1/2 in a rat model of knee arthritis (P <0.05). Alendronate can promote glycosaminoglycans and MMP-3 expression, and synthesis of BMP-2 and BMP-4 by inhibiting ERK pathway, inhibiting the secretion of inflammatory factors, thus ameliorating knee arthritis.

Comparison of Properties Determined Using Electromechanical Assessment (Arthro-BSTTM) With Macroscopic and Histological Properties in Symptomatic Human Articular Cartilage of the Hip

Background: Cartilage degeneration is assessed using various methods. Although macroscopic evaluation can measure cartilage degeneration directly, it cannot accurately assess cartilage properties. Histological examination is one of the most accurate methods for evaluating cartilage degeneration. However, it is invasive and requires collection of cartilage tissue. By contrast, the Arthro-BSTTM probe can assess cartilage properties noninvasively. This study aimed to evaluate the effectiveness of the Arthro-BST for assessing cartilage degeneration by comparing macroscopic evaluation (International Cartilage Repair Society [ICRS] classification) and histological evaluation (modified Mankin score and Osteoarthritis Research Society International [OARSI] histological grade).Methods: Fourteen femoral heads were excised from 13 patients during surgery to treat hip osteoarthritis or femoral fracture. The ICRS score was used for macroscopic evaluation of cartilage degeneration. The Arthro-BST was applied at sites matching the areas of cartilage damage. The sites assessed using the ICRS classification and Arthro-BST were evaluated histologically (modified Mankin score and OARSI histological grade), and these were compared with the Arthro-BST results.Results: ICRS classification identified significant differences between grades 1 and 3 (p < 0.01), grades 1 and 4 (p < 0.01), grades 2 and 3 (p < 0.01), and grades 2 and 4 (p < 0.01). Significant correlations were observed between the Arthro-BST results and the ICRS score, modified Mankin score (structure, cellularity, matrix staining, total score), and OARSI histological grade.Conclusions: In the assessment of hip osteoarthritis, Arthro-BST results correlated with those of macroscopic and histological evaluation. The Arthro-BST is useful for assessing hip osteoarthritis and may be helpful for the noninvasive assessment of cartilage degeneration.

The Expression of αvβ3 and Osteopontin in Articular Cartilage of Patients with Knee Osteoarthritis and Its Correlation with Disease Severity and Chondrosenescence

Background: Osteoarthritis(OA) is the most common joint pathological disease associated with aging,previous observations have revealed that both osteopontin (OPN) and αvβ3 integrin are expressed in chondrocytes and both could as the biomarker for the progression of knee OA .The research aimed to comprehend the expressions of OPN and αvβ3 integrin and the chondrocyte senescence levels in OA. Methods: 48 cartilage tissues from normal and knee OA patients were divided into four groups of normal,minor,moderate, severe lesions based on the Mankin score. Immunohistochemistry and western blot were used to determine the expresssions of αvβ3,OPN and SAβ-gal in articular cartilage,Then Spearman’s correlation was used to analyze the correlations between Mankin Scores and αvβ3, OPN and SAβ-gal. The pearson correlation analysis was used to analyze the correlation among the αvβ3, OPN and SAβ-gal. Results: The expression of OPN and αvβ3 and SAβ-gal in articular cartilage were explored. αvβ3, OPN and SAβ-gal proteins all elvated in OA cartilage, the correlation coefficient between the Mankin score and the average optical density value of αvβ3, OPN, SAβ-gal were r=0.60,r=0.75,r=0.87,respectively, all p＜0.001,the correlation between the average optical density value of αvβ3 and OPN was r=0.3191, p<0.05, the correlation between αvβ3 and SAβ-gal was r=0.4955, p<0.001 , the correlation between OPN and SAβ-gal was r=0.7821, p<0.001.Conclusion: the correlation between αvβ3 , OPN and SAβ-gal expression in articular cartilage might be important to the OA progression and pathogenesis. Nonetheless, more researches are needed to elucidate the exact contribution of αvβ3 , OPN and SAβ-gal in the degenerative process of OA.

Joint hemorrhage accelerates cartilage degeneration in a rat immobilized knee model

Background Joint hemorrhage is caused by trauma, ligament reconstruction surgery, and bleeding disorders such as hemophilia. Recurrence of hemorrhage in the joint space induces hemosiderotic synovitis and oxidative stress, resulting in both articular cartilage degeneration and arthropathy. Joint immobilization is a common treatment option for articular fractures accompanied by joint hemorrhage. Although joint hemorrhage has negative effects on the articular cartilage, there is no consensus on whether a reduction in joint hemorrhage would effectively prevent articular cartilage degeneration. The purpose of this study was to investigate the effect of joint hemorrhage combined with joint immobilization on articular cartilage degeneration in a rat immobilized knee model. Methods The knee joints of adult male rats were immobilized at the flexion using an internal fixator from 3 days to 8 weeks. The rats were randomly divided into the following groups: immobilized blood injection (Im-B) and immobilized-normal saline injection (Im-NS) groups. The cartilage was evaluated in two areas (contact and non-contact areas). The cartilage was used to assess chondrocyte count, Modified Mankin score, and cartilage thickness. The total RNA was extracted from the cartilage in both areas, and the expression of metalloproteinase (MMP)-8, MMP-13, interleukin (IL)-1β, and tumor necrosis factor (TNF)-α was measured by quantitative real-time polymerase chain reaction. Results The number of chondrocytes in the Im-B group significantly decreased in both areas, compared with that in the Im-NS group. Modified Mankin score from 4 to 8 weeks of the Im-B group was significantly higher than that of the Im-NS group only in the contact area. The expression of MMP-8 and MMP-13 from 2 to 4 weeks and TNF-α from 2 to 8 weeks significantly increased in the Im-B group compared with those in the Im-NS group, but there was no significant difference in IL-1β expression. Conclusions The results showed that joint hemorrhage exacerbated immobilization-induced articular cartilage degeneration. Drainage of a joint hemorrhage or avoidance of loading may help prevent cartilage degeneration during joint immobilization with a hemorrhage.

Joint hemorrhage accelerates cartilage degeneration in a rat immobilized knee model

Background: Joint hemorrhage is caused by trauma, ligament reconstruction surgery, and bleeding disorders such as hemophilia. Recurrence of hemorrhage in the joint space induces hemosiderotic synovitis and oxidative stress, resulting in both articular cartilage degeneration and arthropathy. Joint immobilization is a common treatment option for articular fractures accompanied by joint hemorrhage. Although joint hemorrhage has negative effects on the articular cartilage, there is no consensus on whether a reduction in joint hemorrhage would effectively prevent articular cartilage degeneration. The purpose of this study was to investigate the effect of joint hemorrhage combined with joint immobilization on articular cartilage degeneration in a rat immobilized knee model.Methods: The knee joints of adult male rats were immobilized at the flexion using an internal fixator from 3 days to 8 weeks. The rats were randomly divided into the following groups: immobilized blood injection (Im-B) and immobilized-normal saline injection (Im-NS) groups. The cartilage was evaluated in two areas (contact and non-contact areas). The cartilage was used to assess chondrocyte count, Modified Mankin score, and cartilage thickness. The total RNA was extracted from the cartilage in both areas, and the expression of metalloproteinase (MMP)-8, MMP-13, interleukin (IL)-1β, and tumor necrosis factor (TNF)-α was measured by quantitative real-time polymerase chain reaction.Results: The number of chondrocytes in the Im-B group significantly decreased in both areas, compared with that in the Im-NS group. Modified Mankin score from 4–8 weeks of the Im-B group was significantly higher than that of the Im-NS group only in the contact area. The expression of MMP-8 and MMP-13 from 2 to 4 weeks and TNF-α from 2 to 8 weeks significantly increased in the Im-B group compared with those in the Im-NS group, but there was no significant difference in IL-1β expression.Conclusions: The results showed that joint hemorrhage exacerbated immobilization-induced articular cartilage degeneration. Drainage of a joint hemorrhage or avoidance of loading may help prevent cartilage degeneration during joint immobilization with a hemorrhage.

Joint hemorrhage accelerates cartilage degeneration in a rat immobilized knee model

Background: Joint hemorrhage is caused by trauma, ligament reconstruction surgery, and bleeding disorders such as hemophilia. Recurrence of hemorrhage in the joint space induces hemosiderotic synovitis and oxidative stress, resulting in both articular cartilage degeneration and arthropathy. Joint immobilization is a common treatment option for articular fractures accompanied by joint hemorrhage. Although it is apparent that joint hemorrhage has negative effects on the articular cartilage, there is no consensus whether a reduction in joint hemorrhage is effective to prevent articular cartilage degeneration. The purpose of this study was to investigate the articular cartilage degeneration induced by a combination of joint hemorrhage and joint immobilization in a rat immobilized knee model. Methods: The knee joints of adult male rats were immobilized at the flexion using an internal fixator from 3 days to 8 weeks. The rats were randomly divided into the following groups: immobilized blood injection (Im-B) and immobilized-normal saline injection (Im-NS) groups. The cartilage was evaluated in two areas (contact and non-contact areas). The cartilage was used to assess chondrocyte count, Modified Mankin score, and cartilage thickness. The total RNA was extracted from the cartilage in both areas, and the expression of metalloproteinase (MMP)-8, MMP-13, interleukin (IL)-1β, and tumor necrosis factor (TNF)-α was measured by quantitative real-time polymerase chain reaction. Results: The number of chondrocytes in the Im-B group significantly decreased in both areas, compared with that in the Im-NS group. Modified Mankin score from 4–8 weeks of the Im-B group was significantly higher than that of the Im-NS group only in the contact area. The expression of MMP-8 and MMP-13 from 2 to 4 weeks and TNF-α from 2 to 8 weeks significantly increased in the Im-B group compared with those in the Im-NS group, but there was no significant difference in IL-1β expression. Conclusions: The results showed that joint hemorrhage exacerbated immobilization-induced articular cartilage degeneration. Drainage of a joint hemorrhage or avoidance of loading may help prevent cartilage degeneration during joint immobilization with a hemorrhage.