A New Polyoxypregnane Glycoside from the Roots of Dregea volubilis (L.f) Benth. ex Hook. f and its Chondroprotective Effect

Problem statement: Dregea genus (Asclepiadaceae) is well known for the rich of steroid pregnane contents and these plants are famous for the potential to be applied as alternative biological activities. Dregea volubilis is the only species of Dregea genus in Thailand. The chemical and biological investigations of this plant are interesting to bioassay-guided fractionation, particularly chondroprotective effect. Approach: The research was carried out to extract, isolate, purify and elucidate structure of the active compound from the roots Dregea volubilis. Both of the solvent extracts and isolated compound were evaluated with kinds of chondroprotection. i.e., S-GAG), HA, UA and production of matrix metalloproteinase-2 (MMP-2). Results: Polyoxypregnane glycoside (PGG) or 12-0-benzoyl-8, 11-ditigloyl-3β, 8β, 11α, 12β, 14β-pentahydroxy-pregn-14-ol, 20-one,-3-0-methyl-β-D-allopyranosyl (1→4)-β-D-thevetopyranoside was isolated from the active ethyl acetate extract of the roots Dregea volubilis. The spectroscopic techniques were provided for success in structure determination. In addition, a new compound was the most powerful to biological activities. Chondroprotective effect of PPG on the degradation of sulfated glycosaminoglycan (S-GAG), hyaluronan (HA), uronic acid (UA) and production of matrix metalloproteinase-2 (MMP-2) in interleukin-1β (IL-1β)-stimulated porcine articular cartilage were also assessed. PGG was interestingly effective in reducing IL-1β induced S-GAG, HA release from cartilage explant and MMP-2 activity. Furthermore, PPG can reverse effect of IL-1β-reduced the levels of uronic acid remaining in cartilage tissue. Conclusion: The PGG was possessed a potent chondroprotective activity using the IL-1β stimulated cartilage explant model. Therefore, it is possible to use this compound as a new pharmacological agent for the management of degenerative joint diseases.