Studies On The Phosphatidylcholine Containing Sodium Hyaluronate Preparation And The Mechanism Of Its Remedying Osteoarthritis

Osteoarthritis (OA) is one of chronic degenerative joint diseases, which is especially harmful to the health of aged people. OA often occurs in knee joints. With the aging of social population, the incidence rate of OA is increasing. Nowadays, there are about 60 million to 70 million people suffer from this kind of diseases to some extent in our country. According to the classification of American College of Rheumatology (ACR), OA is divided into primary OA and secondary OA. The primary OA is the focal point in present investigation.Phospholipid (PL) is an important component of joint synovial fluid (SF). It has the peculiar effect on joint lubrication. It also has other various physiological functions such as scavenging oxygen-derived free radicals, inhibiting the hydration of cartilage, preventing adhesion, as well as inhibiting the gel fusion of the articular interface in the normal articular cartilage boundary.In order to make a good preparation for the treatment of OA, this paper prepared one kind of SF like preparation, phosphatidylcholine (PC) containing sodium hyaluronate (SH) injection. The effects and the mechanism of the preparation in remedying osteoarthritis were also studied. The main research contents and results are as follows. 1. Preparation of PC with high puritySoybean PC and egg yolk PC was extracted and purified with the methods of organic solvent extraction and column chromatography respectively. The prepared PCs had the same of UV and IR spectra patterns as that of reference PC. The purity ofthe prepared PCs were more than was 99.0% analyzed by TLC.2. Preparation of PC containing SH preparations (PSH injections)Three liposome suspensions with three different concentrations of egg yolk PC (0.1%, 0.2% and 0.4%) were prepared. Three PC-SH compound injections, PSH(O.l), PSH(0.2) and PSH(0.4), were obtained by mixing the three liposome suspensions into 1.0% of SH solution respectively. The main quality criterion of PSH injections were established. The stability studies of the injections showed that they were stable. The shape of lipsomes in PSH injections was evenly-dispersed in a sphere like look under electronic microscope. The rheological properties of PSH injections were similar to that of the normal joint SF.3 Investigation of the effects of PSH injections on OA animal modelsThe effects of the three PSH injections in the treatment of OA were investigated in OA rabbit models induced by papain. During the experiment, the PSH injections were injected into the knee joint of the rabbits. After 5 weeks, the knee joint samples were taken and observed with optical and electronic microscopes. On the basis of the results showed that all PSH injections had significant effects on reducing the symptoms of OA evaluated with Mankin grade of arthritis severity. PSH(O.l) and PSH (0.2) had better effects than 0.1% SH did.4 Study on the mechanism of PSH injections for remedying OAThe content of glycosaminoglycans (GAG), which were obtained by alkaline hydrolysis and protease digestion from the PSH treated knee joint cartilage of OA rabbit models, was determined by azur A colorimetry method. The content of hyaluronic acid (HA) was measured by radioimmunoassay. The results showed that PSH injections could increase the content of the PG.The effects of PSH injections on the level of IL-lp, IL-6 and TNF-a in SF after treatment were also studied. The results showed that PSH injections could significantly inhibit the expression level of IL-ip and TNF-a and enhance the expression level of IL-6. The effects of the PSH injections were better than that of SH solution.On the basis of the results it can inferred that the remedying effect of PSH maybe partly realized by that PC could supplement PL to SF and articular surfaces, forma PL bilayer on the articular surfaces, improve physiological function of patholoical SF, reduce the expression level of inflammatory factors such as IL-lp and TNF-a and eventually lessen the joint inflammation.The main achievements and conclusions of this paper are as follows:(1) The preparation procedure of soybean and egg PC was studied and high purity PC(>99.0%) was obtained through this procedure. The procedure is suitable for the high purity PC production in industrial scale.(2) Stable and quality controllable PSH injections were prepared by mixing liposome suspensions into 0.1% SH solution.(3) It was found that the rheological properties of PSH injections were similar to that of the normal joint SF, so PSH injections can be used as artificial SF.(4) Animal model experiment showed that PSH injections could protect articular cartilage, lessen inflammation and significantly improve OA symptoms.(5) The mechanism of PSH from the viewpoint of molecular biology investigated. PSH injections could significantly inhibit the expression level of IL-ip and TNF-a and enhance the expression level of IL-6, hence inhibit the degradation of OA cartilage.