Osteoartrite experimental efeito analgésico e condroprotetor de um polissacarídeo de elevado peso molecular

Abstract

Osteoarthritis is the leading cause of joint pain in the world. Although there are many treatment modalities, there is no drug able to reduce or recover structural damage. With the purpose of investigate if a protein-free guar gum (DGG) polyssacharide could promote chondral protection and or analgesic effects from osteoarthritis, even after molecular modifications, it was oxidized (DGGOX) or sulfated (DGGSU) by insertion of new groups in C-6 (manose) and C-6 (galactose), for DGGOX and DGGSU, respectively. Pain and chondral damage were evaluated. The new molecules were tested to confirm its alterations. Then, rats were subjected to anterior cruciate ligament transection (ACLT) of the rigth knee, were submted to a treatment with intraarticular 100 µg DGG, DGGOX or DGGSU solutions and saline. The joint pain was evaluated using the articular incapacitation test, at days 4–7 after ACLT and joint damage was assessed using histology and biochemistry as the chondroitin sulfate (CS) content of cartilage. The molar mass of CS samples was obtained by comparing their relative electrophoretic mobility to standard CS. Another two groups that were done to investigate joint damage, undergone ACLT, received a solution of 100µg DGG or saline weekly, from days 7 to 70. DGG administration, but not DGGOX or DGGSU, significantly inhibited joint pain. DGG significantly reversed the increase in CS, its reduced electrophoretic mobility, and histological changes following ACLT, as compared to vehicle. Structural integrity accounts for DGG benefits in experimental osteoarthritis.