The contribution of side chains to antitumor activity of a polysaccharide from Codonopsis pilosula.

In order to assess the potential contribution of the side chains of a polysaccharide (CPPW1) from the roots of Codonopsis pilosula to the biological activities, we chose CPPW1 and its backbone (CPPW1B) as the research targets to compare them with their antitumor and immunomodulatory activity. The results demonstrated CPPW1 could significantly inhibit the tumor growth of H22-bearing mice and simulate lymphocyte proliferation. Meanwhile the phagocytic capability of macrophages and NO production were also enhanced. However, CPPW1B could only inhibit the tumor weight and did not work to immune system at all. Additionally, both CPPW1 and CPPW1B had no toxicity in vivo. Taken together with all data, we found the sugar side chains attached to the backbone of CPPW1 played a pivotal role in fighting against tumor and activating immune system.