Achyranthes bidentata Polysaccharide Activates Nuclear Factor-Kappa B and Promotes Cytokine Production in J774A.1 Cells Through TLR4/MyD88 Signaling Pathway.

Achyranthes bidentata Blume, a traditional Chinese medicine, is widely acknowledged for its function of invigorating the liver and kidneys and as a stranguria-relieving diuretic and used in the treatment of edema, gonorrhea, and other diseases. Polysaccharide (ABPS), isolated from Achyranthes bidentata Blume, has been demonstrated to have multiple biological activities including immunomodulatory effects. However, the mechanisms underlying the effects of ABPS have not been fully investigated. The present study is conducted to explore the underlying mechanism of immunomodulatory activities of ABPS. Results showed that ABPS significantly increased the secretion of IL-1ß and TNF-α in J744 A.1 cells. Nitric oxide (NO) also significantly increased after ABPS treatment. The special antibodies (Toll-like receptor 4 (TLR4) antibody and CD14/TLR4 antibody) significantly decreased the activation, while the Toll-like receptor 2 (TLR2) antibody could not abolish this activation. Meanwhile, pyrrolidine dithiocarbamate (PDTC), a specific inhibitor of NF-κB, remarkably inhibited the secretion of IL-1ß and TNF-α induced by ABPS in J744 A.1 cells. Western blotting (WB) and confocal laser scanning microscopy (CLSM) showed that ABPS promoted NF-κB translocation into the nucleus. Furthermore, the mRNA and protein expression of TLR4 and MyD88 were significantly increased after ABPS treatment. Taken together, these findings suggested that the immunomodulatory mechanism of ABPS was associated with the secretion of cytokines by stimulating the NF-κB pathway through TLR4/MyD88 signaling.

Cardioprotective effect of the polysaccharide from Ophiopogon japonicus on isoproterenol-induced myocardial ischemia in rats.

The polysaccharide (OJP1), extracted from the root of Ophiopogon japonicus, is a well-known traditional Chinese medicine used to treat cardiovascular diseases. The present study was set up to investigate the cardioprotective effect of OJP1 on isoproterenol (ISO)-induced myocardial ischemia injury in rats. Results showed that pretreatment with OJP1 (100, 200 and 300 mg/kg) significantly reduced ISO-induced ST-segment elevation and the heart index, attenuated the levels of marker enzymes (AST, LDH, CK and CK-MB), along with a significantly enhanced the activities of ATPases. Moreover, pretreatment with OJP1 not only enhanced the activities of SOD, GPx and CAT in serum and myocardium, but also decreased the level of MDA. The biochemical and histopathological analysis also showed that OJP1 can alleviate the myocardial injury induced by ISO. Taken together, our results indicated that oral administration of OJP1 offered significant cardioprotective effect against the damage induced by ISO through enhancement of endogenous antioxidants.

Cardiovascular protective effect of polysaccharide from Ophiopogon japonicus in diabetic rats.

Ophiopogon japonicus (Thunb.) Ker-Gawl is a well known traditional Chinese medicine used to treat cardiovascular and chronic inflammatory diseases for thousands of years. The present study was set up to investigate the protective effects of O. japonicus polysaccharide (OJP1) on cardiovascular injuries in diabetic rats. Results showed that OJP1 significantly reduced the MDA concentration and increased the activities of GPx, CAT and SOD in heart of diabetic rats. The levels of AGE, hs-CRP, sICAM-1, NO and ET-1 in diabetic rats were significantly reversed by OJP1 treatment. In addition, the level of ET-1 mRNA was decreased significantly, whereas eNOS mRNA level was increased after administration of OJP1. Meanwhile, the histopathological analysis showed that OJP1 alleviates the heart injury in diabetic rats. Together, these results suggest that OJP1 maintains the antioxidant enzyme levels and improves cardiovascular performance in diabetic rats.

Sargassum fusiforme polysaccharide activates nuclear factor kappa-B (NF-κB) and induces cytokine production via Toll-like receptors.

This study was designed to investigate the mechanism of macrophage activation by the Sargassum fusiforme polysaccharide (SFPS). As a result, SFPS significantly enhanced cytokines and nitric oxide (NO) productions in peritoneal macrophages, and stimulated macrophages to produce the cytokines and NO through the induction of their genes expression. The pretreatment of peritoneal macrophages with special antibodies [Toll-like receptors (TLRs) antibody] significantly blocked SFPS-induced tumor necrosis factor alpha (TNF-α) and NO production. Furthermore, pyrrolidine dithiocarbamate (PDTC), a specific inhibitor of NF-κB, effectively suppressed SFPS-induced TNF-α and interleukin 1ß (IL-1ß) secretion in peritoneal macrophages, indicating that SFPS stimulated macrophages to produce cytokines through the NF-κB pathway and the result was further confirmed by the experiment of Western blotting (WB) and confocal laser scanning microscope (CLSM). Taken together, these results suggest that SFPS-mediated induction of cytokines and NO production in macrophages is mediated, at least in part, by TLRs/NF-κB signaling pathway.