Bioactivity of high-molecular-weight constituents of Cistanche tubulosa

Cistanche tubulosa (Schrenk) R. Wight is traditionally eaten in Hotan in Xinjiang Uygur Autonomous Region, an area known for longevity and oasis in the Takla-Makan Desert. In this study, we investigated whether high-molecula-weight constituents of C. tubulosa have the same effects on human cell lines as we previously reported for C. salsa. As per results, C. tubulosa dialysate (CTD) prepared using a 3,500-Da molecular weight cut-off dialysis membrane enhanced IgM production in B-cell line BALL-1 and IgG production in B-cell line HMy-2, induced cell proliferation in BALL-1 and T-cell line Jurkat, and oppositely inhibited cell proliferation in B-cell line Namalwa. Using gel filtration chromatography, we found that, similar to C. salsa, the two activities (i.e., enhancement of IgM production and growth inhibition) were concentrated in different fractions. These results suggest that C. tubulosa contains high-molecular-weight constituents having immunomodulatory and direct anti-cancer effects, which seem to contribute to the longevity.