Hydrogel of Guar Gum in experimental osteoarthritis in rats

Commercial Guar Gum, a galactomannan polysaccharide, was purified by the use of two subsequent methods, including precipitation with Fehling solution in order to eliminate protein impurities. The protein content (3.6%) was totally removed. Glutaraldehyde cross-linked gels were prepared with purified (GGP) and unpurified gum (GGU). The viscosity of the gels is similar to that of Hylan G-F 20, a commercial substitute of hyaluronic acid, used in viscosupplementation in human osteoarthritis. Guar Gums (gel and solution) were injected intra-articularly into the knee joints of rats subjected to experimental CIA and the effect in hypernociception and cells influx measured. GGU promoted hypernociception and cell influx in naive rats. GGP was innocuous to naive rats and inhibited hypernociception, both as a gel or solution, to the same extent as Hylan G-F. GGP promotes analgesia in OA due to its carbohydrate component.