Abstract:

Objective: To investigate the antitumor activity of polysaccharides from Gracilaria chouae (GLP) in vivo.
Methods: S180 sarcoma mouse model was established and used for the determination of antitumor activity of GLP in vivo.
In addition, the underlying mechanism was explored by measuring biochemical parameters of immune system in the mice.
Results: GLP definitely had inhibitory effect on S180 sarcoma in vivo. An inhibition rate of 34.75% was obtained with
intraperitoneal injection at a dose of 100 mg/(kg·d), higher than that (31.35%) of the medium-dose intragastric administration
group (200 mg/(kg·d)). Immune organ indices of tumor-bearing mice significantly increased (P < 0.01). Additionally, the
proliferation and the differentiation of lymphocytes was activated by GLP administration. The levels of IL-2 and IFN-γ
significantly increase (P < 0.01), while the level of IL-10 significantly decreased (P < 0.01). GLP showed good protection on
the immune system. Conclusion: GLP had strong anti-tumor activity and was more effective when given by intraperitoneal
injection than by intragastric administration. The anti-tumor effect of GLP was mainly achieved by improving immune
function in mice.

Key words: Gracilaria chouae polysaccharides (GLP), antitumor, immunological effect