Dioscorea Phytocompounds Enhance Murine Splenocyte Proliferation Ex Vivo and Improve Regeneration of Bone Marrow Cells In Vivo
Figure 2
Effect of ethanol-partitioned DsCE fractions of Dioscorea tuber extract on the proliferation of murine splenocytes, alone or in combination with IL-2. (a) Splenocytes isolated from BALB/c mice were incubated with varying amounts (0–1000 g mL−1) of DsCE-I, -II or -III. Bars with different alphabets represent significant differences between treatments. (b) Splenocytes were incubated with increasing amounts (0–500 g mL−1) of DsCE-II of D. batatas Decne, in combination with 2 ng mL−1 IL-2 in culture medium. The cpm value for splenocytes treated with 2 ng mL−1 IL-2 alone was determined at 1,864 ± 272. Open circles denote the growth activity of splenocytes treated with DsCE-II; inverted open triangles show the experimentally observed stimulatory activity when DsCE-II and IL-2 were added together to test cells; filled squares indicate the theoretical total activity determined by adding the individually obtained activities of DsCE-II and IL-2 as a sum. This result indicates that DsCE-II and IL-2 have a synergistic effect rather than an additive effect. CPM values that differed significantly from theoretical sum are marked. (c) The specific DsCE-II fractions extracted from the tuber of four different species/cultivars of Dioscorea spp. plants were tested alone or in combination with IL-2 for their abilities to stimulate splenocyte cell proliferation in culture. After treatment for 48 h, test cells were then labeled with 3H-thymidine and harvested for assay as described in the ‘Methods’ section. The data represent the mean ± SD of triplicate cell culture samples. Two other independent experiments were repeated and showed similar results. Significant difference (***) between the group of DsCE-II with IL-2 coincubation and theoretic sum. **.
