Effects ofPortulaca oleracea L.Polysaccharides on Phenotypic and Functional Maturation of Murine Bone Marrow Derived Dendritic Cells

Abstract

Portulaca oleracea L. is an annual plant widely distributed from the temperate to the tropical zones. POL-P3b, a polysaccharide fraction purified from Portulaca oleracea L., is able to enhance immunity and inhibit tumor formation. Induction of antitumor immunity by dendritic-tumor fusion cells can be modulated by their activation status. Mature dendritic cells are significantly better than immature dendritic cells at cytotoxic T-lymphocyte induction. In this study, we analyzed the effects of POL-P3b on the maturation and function of murine bone-marrow-derived dendritic cells (DCs) and relevant mechanisms. The phenotypic maturation of DCs was confirmed by flow cytometry. We found that POL-P3b upregulated the expression of CD80, CD86, CD83, and major histocompatibility complex class II molecules on DCs, stimulated production of more interleukin (IL)-12, tumor necrosis factor-α, and less IL-10. Also, DCs pulsed POL-P3b and freeze-thaw antigen increased DCs-driven T cells' proliferation and promoted U14 cells' apoptosis. Furthermore, the expression of TLR-4 was significantly increased on DCs treated by POL-P3b. These results suggested that POL-P3b may induce DCs maturation through TLR-4. Taken together, our results may have important implications for the molecular mechanisms of immunopotentiation of POL-P3b, and provide direct evidence to suggest that POL-P3b should be considered as a potent adjuvant nutrient supplement for DC-based vaccines.

The Possible Therapeutic Effects of Some Medicinal Plants for Chronic Cough in Children

“…Furthermore, POL-P3b significantly increased the expression of Toll-like receptor 4 (TLR-4) on DCs treated. The findings confirm that POL-P3b is able to induce DCs maturation through TLR-4 [ 71 ]. The oral administration of P. oleracea polysaccharides significantly and dose-dependently increases stimulation indices (SI) of T lymphocytes and B lymphocytes in Wistar rats [ 72 ].…”

Anti-Diabetic Effect of Portulaca oleracea L. Polysaccharideandits Mechanism in Diabetic Rats

“…It is a traditional Chinese herb now widely distributed throughout the world. The active ingredients include polysaccharides [21], fatty acids [22], flavonoids [22], coumarin [22], and alkaloids [23]. It is rich in antioxidant vitamins and omega-3 fatty acids [20] and can be used as a vegetable as well as for various curative purposes in health care, especially in preventing some cardiovascular diseases and maintaining a healthy immune system [24].…”

In Vitro Evaluation of Cytotoxic and Antiproliferative Effects of Portulaca oleracea Ethanolic Extracton on HeLa Cell Line

“…It has been indicated that POL-P3b possesses the activity of inhibiting cervical cancer cell growth in vitro and in vivo at a concentration and time-dependent manner (36). POL-P3b (watersoluble polysaccharide) is a polysaccharide fraction purified from Portulaca oleracea L. and it is able to enhance immunity and inhibit tumor formation (37). Moreover, it was found that P. oleracea methanol extract was able to reduce DNA synthesis that was detected in BrdU (5-Bromo-2'-deoxyuridin) assay and arrest both CNE-1 and HeLa cell under S phase of the cell cycle (24,38).…”