Structural elucidation and anti-diabetic osteoporotic activity of an arabinogalactan from Phellodendron chinense Schneid

Phellodendron chinense Schneid. was widely used as a medicinal herb for the treatment of diabetic osteoporosis in China. In this study, an arabinogalactan, named as PPCP-1, was isolated from the bark of Phellodendron chinense Schneid., and purified by DEAE-cellulose DE52 and Sephacryl S-200 HR column chromatography. The structure of PPCP-1 was characterized as a repeating unit consisting of -> 3)-beta-D-Galp-(1 ->, -> 3,6)-beta-D-Galp-(1 ->, -> 5)-alpha-L-Araf-(1 ->, -> 4)-alpha-D-Glcp-(1 ->, -> 3)-alpha-D-Glcp-(1 ->, -> 4)-alpha-D-Manp-(1 -> with branches of -> 5)-alpha-L-Araf-(1 ->, -> 3,5)alpha-L-Araf-(1 -> and terminal alpha-L-Araf. Pharmacologically, the oral administration of PPCP-1 preserved osteoporosis associated with hyperglycemia by inhibiting alpha-glucosidase activity, improving glucose tolerance, decreasing the accumulation of advanced glycation end products (AGEs), as well as down-regulating the expression of receptor for AGEs in tibias of streptozotocin-induced diabetic rats. Collectively, the present study suggested that the arabinogalactan PPCP-1 from Phellodendron chinense Schneid. might potentially be used as functional foods for bone health and/or developed for drug discovery for alleviating diabetic osteoporosis.

Automated summary

PPCP-1, an arabinogalactan isolated from Phellodendron chinense Schneid., shows potential in protecting against diabetic osteoporosis through various mechanisms, making it a potential functional food or drug for bone health.