Study On Intra-articular Low Molecular Weight Heparin And Sodium Hyaluronate Compound Gel Injection In Treating Knee Osteoarthritis

Osteoarthritis (OA) is a group disease of different causes but similar biology, morphology and clinical manifestations. Its pathogenesis is not yet clear. OA is a very complicate process, and is the result of interaction of multiple factors, such as age, obesity, inflammation, inherit, endocrine abnormalities, climate and so on. With the accelerated ageing of population, more and more harm comes from OA. In China, 60 million to 70 million people or so are suffering from OA with different degrees.Low molecular weight heparin (LMWH) is one of glycosaminoglycans (GAG) in a more complex structure. The latest research shows that LMWH not only has effects of anticoagulant, anti-thrombosis, blood lipid-regulating and other variety of biological activities, but also improves local blood circulation, accelerates wound healing, promotes connective tissue repair, and possesses swelling-eliminating, anti-inflammatory, anti-allergic activities, etc.Sodium hyaluronate (SH) is an important component of synovial fluid and articular cartilage with the extensive presence in polymorphic cartilage cells and synovial cells. SH plays an important part in lubricating, buffering and screening joints and cartilage, constructing and repairing articular cartilage. SH injected into articular cavity has become the main method in treating OA, which can increase the viscoelasticity and lubrication of joint synovial fluid, be better to improve the process of OA with restoring the viscoelasticity of synovial membrane and cartilage matrix and easing inflammation. This research studied LMWH and SH (LMWH-SH) compound gel injection, LMWH injection and their therapeutic effects as well as mechanisms on OA. The following outcomes have been achieved in this study.1 Preparation of LMWH-SH injection and LMWH injectionThe preparation of certain concentration of LMWH-SH compound gel injection and LMWH injection was studied and the main index of quality control for LMWH-SH compound gel injection was established. The results showed that the compound gel injection had a good stability.2 Investigation of therapeutic effect of LMWH-SH and LMWH injections in treating OARabbit knee OA model induced by papain was established. The test groups received respectively intra-articular injections of LMWH-SH and LMWH, with normal saline (NS) and SH injection used as controlled.After administration for five weeks, the microscopic observation on articular cartilage was made and the changes of articular cartilage and synovial fluid were studied. The results showed that the LMWH-SH injection could significantly reduce the symptoms of rabbit knee OA.3 Dose screening test for LMWH-SH compound gel injectionAccording to the results from preliminary test and the physical and chemical properties of injection, the optimum ratio of LMWH to SH was studied. In accordance with the method of preliminary test, the dose screening test was carried on.4 Studies on mechanism of LMWH-SH compound gel injection for OABy alkaline hydrolysis, protease cleavage and ultracentrifugation, the glycosaminoglycan (GAG) from knee cartilage after the treatment was extracted and separated. Total GAG was detected by a colorimetric assay with Azure A (AA). The content of hyaluronic acid (HA) was determined by RIA. The change of proteoglycan (PG) in articular cartilage matrix was investigated after treatment. The results showed that LMWH-SH compound gel injection could significantly increase the content of PG in articular cartilage with OA.The study also detected the contents of interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α) and interleukin-6 (IL-6) in the synovial fluid of different experimental groups. It was found that LMWH-SH compound gel injection could reduce the expression levels of IL-1β, TNF-α. Because of a dual role of IL-6, it was difficult to investigate the severity of OA based on the expression level of IL-6. The results from the investigation of pathological sections and cytokine (CK) levels showed that LMWH-SH compound gel injection had a better therapeutic effect.Based on the findings, it could be speculated that in compound gel injection groups, low concentration of LMWH-SH would be better.The main research results and conclusion in the study were as follows:(1) The preparation technology and production conditions of LMWH-SH, LMWH injection were studied.(2) The quality control and stability of LMWH-SH compound gel injection were investigated.(3) The rheological properties of LMWH-SH injection are similar to that of normal articular synovial fluid reported in the literature, hence, this injection can be used as artificial synovial fluid.(4) The severity and applicability of OA model induced by different concentrations of papain were inspected.(5) The curative effects of compound gel injections of three different ratios of LMWH to SH on OA were investigated with the model of OA. The study showed LMWH-SH compound gel injection could protect articular cartilage, significantly improve the symptoms of rabbit knee OA and reduce inflammatory response.(6) The mechanisms of LMWH-SH compound gel injection on OA was discussed on the basis of immunomolecular level. It was found that LMWH-SH compound gel injection could significantly reduce the contents of IL-1βand TNF-α, accordingly, delay the degradation of cartilage PG and display optimum effects.