Chuanminshen violaceum M.L. Sheh & R.H. Shan

Fiorito, Serena, Epifano, Francesco, Preziuso, Francesca, Taddeo, Vito Alessandro & Genovese, Salvatore, 2018, Selenylated plant polysaccharides: A survey of their chemical and pharmacological properties, Phytochemistry 153, pp. 1-10 : 4

5.2.2. Chuanminshen violaceum M.L. Sheh & R.H. Shan

C. violaceum is a medicinal plant widespread in the Chinese provinces of Sichuan and Hubei. Its use is encoded in the Chinese traditional medicine practice. The polysaccharide fraction from this plant species is claimed to have positive modulatory effects on the immune system ( Feng et al., 2015). Selenylation of polysaccharides from this species has been accomplished in 2016 by Feng and coworkers to obtain a single sample for which however no data about the Se content and yield have been reported. Subsequently the synthesized Se-P was tested for its capacity to enhance immune functions in vitro and in vivo. First the effects on cell bioavailability were assayed on mice splenic lymphocytes. No cytotoxic activity up to a dose of 175 μg/mL were revealed. It is also noteworthy to underline that during this test an appreciable increase of the cell proliferation rate and production of IL-4 and IFN-γ were observed. These latter values were higher than those recorded for the group of cells treated with concanavalin A used as the reference. In vivo tests were carried out using ICR female mice pretreated with rHBsAg, and then administered the Se-P at a dose of 500 μg/mL by a daily subcutaneous injection for 2 weeks. At the end of the experiment (4 weeks) the following biochemical parameters were measured: induction of rHBsAg-specific IgG and effects on T cells proliferation, helper T cells, cytotoxic T lymphocytes, and NK cells. Respect to only vaccinated animals and animals treated with the native polysaccharide, a stronger enhancement of rHBsAg IgG1, IgG2a, and IgG2b contents have been recorded. Administration of the Se-P increased T cells proliferation rate although not at levels comparable to those induced by concanavalin A. The production of IL-2, IL-4, and IFN-γ by CD4 + and CD8 + T cells was by far higher than all other groups of animals. As a parallelism Se-P treatment led to an increase and enforcement of the rHBsAg specific cytotoxic T lymphocytes capacity. In fact, the percentage of antigen-specific lysis of target cells in the Se-P group was 75.7%, while for mice treated with the parent polymer and in vaccinated only animals were 60.8% and 34.3% respectively. A similar pattern was recorded for NK cells.