Abstract: The purpose of the present work was to study the antioxidant effect of water soluble polysaccharides from Hippophae rhamnoides leaf tea (WPHT), a commercially available product processed from the leaves of the plant, in subacute aging model mice induced by subcutaneous injection of D-galactose. Fifty mice were divided into 5 groups of 10 ones each: blank control group, aging model group, low-dose 10 mg/(kg·d) WPHT group, middle-dose 50 mg/(kg·d) WPHT group and high-dose 100 mg/(kg·d) WPHT group. The aging model group and the low-, middle- and high-dose WPHT groups were all injected with D-galactose (0.5 g/(kg·d)) subcutaneously for 40 consecutive days, and normal saline instead of D-galactose was given to the blank control group. Intragastric administration of WPHT began after 10 days of subcutaneous injection of D-galactose, was carried out once a day and lasted 30 days. All the mice were fasted for 12 hours after the last intragastric administration of WPHT, and were then scarified to determine the activities of plasma superoxide dismutase (SOD), the content of malondialdehyde (MDA) in plasma, and the activities of SOD, catalase (CAT) and MDA content in liver homogenate. The results revealed that WPHT administration at 50 mg/(kg·d) and 100 mg/(kg·d) could elevate the activities of plasma SOD and liver homogenate SOD and CAT and decrease the contents of plasma MDA and liver homogenate MDA, with a significant difference from the model group (P ＜ 0.05). Therefore, WPHT has antioxidant potential in vivo.

Key words: Hippophae rhamnoides tea, polysaccharides, antioxidation, superoxide dismutase(SOD)