Structural characterization and anti-osteoporotic effect of two β-glucan-like polysaccharides from Pinellia ternata

Pinellia ternata (Thunb.) Breit. has been used in China for more than two thousand years to treat cough and vomiting. P. ternata is rich in polysaccharides; however, current research on the bioactivity of polysaccharides from P. ternata is relatively limited. In particular, there are no reports on their application in the treatment of osteoporosis. In this study, two β-glucan-like polysaccharides were isolated from P. ternata. The primary structures of PTTP50-1-3 and PTTP50-1-4 were comprehensively analyzed using high performance liquid chromatography, gas chromatography-mass spectrometry, and nuclear magnetic resonance. The results indicated that they possess a similar backbone structure. Notably, compared with PTTP50-1-3, PTTP50-1-4 exhibits characteristics of more branching and higher β-glucan content, as well as lower molecular weight. In vitro experiments demonstrated that both PTTP50-1-3 and PTTP50-1-4 could increase the alkaline phosphatase activity of osteoblastic MC3T3-E1 cells. In addition, PTTP50-1-4 was able to enhance the mineralization of MC3T3-E1 cells by upregulating the expression of Runx2, Osx, Bmp2, Ocn, Opn, and Bsp. These findings suggest that P. ternata polysaccharides with a β-glucan-like structure may possess strong anti-osteoporotic potential, which provide a theoretical foundation for further research and development of P. ternata polysaccharides in the prevention and treatment of osteoporosis.