Effects of Marsdenia tenacissima polysaccharide on the immune regulation and tumor growth in H22 tumor-bearing mice

• A homogeneous polysaccharide (MTP) was extracted and fractioned from the the dried rattan of Marsdenia tenacissima.
• MTP could improve the immune functions in normal mice.
• MTP could inhibit the growth of tumor and increase the spleen index, thymus index and ALB level in H22 tumor-bearing mice.
• MTP could reduce serum VEGF levels, and increase TNF-α and IL-2 levels in H22 tumor-bearing mice.
• MTP could improve GSH-Px, SOD and CAT activities, and reduce MDA content in liver tissue of H22 tumor-bearing mice.

One water-soluble polysaccharide (Marsdenia tenacissima polysaccharide, MTP), with an average molecular weight of 4.9 × 104 Da, was isolated from the dried rattan of M. tenacissima. MTP contained 93.8% carbohydrates, 5.6% proteins and 21.3% uronic acid, and were composed of arabinose, mannose, galactose, xylose, glucuronic acid at a molar ratio of 9.1, 17.7, 30.2, 22.4 and 20.6. The experiments on the animals showed that MTP could increase the serum hemolysin, promote the formation of antibody-forming cells and improve the phagocytosis of mononuclear macrophage in normal mice. Meanwhile, MTP could also inhibit the growth of tumor in H22 tumor-bearing mice dose-dependently, and increase the spleen index, thymus index and serum albumin level in the mice. In addition, MTP could elevate the serum level of TNF-α and IL-2, increase the activity of GSH-Px, CAT and SOD in the liver tissue, and reduce the content of VEGF and MDA. These results suggest that MTP can regulate the immune function in mice and suppress the growth of tumor in H22 tumor-bearing mice, and its antitumor activity may be related to its antioxidant and immunomodulatory effects.