Immunosuppressive alkaloids from Narcissus tazetta subsp. Chinensis and the mechanism of (+)-narciclasine in vitro and in vivo.

Three previously undescribed and sixteen known alkaloids were bioguidedly isolated from the bulbs of Narcissus tazetta subsp. chinensis (M.Roem.) Masamura & Yanagih. The structures were elucidated by spectroscopic data, including HRESIMS, NMR, and ECD. Eleven of the isolated alkaloids exhibited immunosuppressive activity on the proliferation of human T cells. (+)-Narciclasine (18) showed the most significantly suppressive activity with an IC50 value of 14 ± 5 nM. In vitro, (+)-narciclasine (18) blocked NF-κB signal transduction, but did not affect PI3K/AKT signal transduction. What was more, (+)-narciclasine significantly reduced ALT and AST levels and alleviated liver damage induced by ConA in AIH mouse model.

Monoterpenoid Indole Alkaloids from Kopsia officinalis and the Immunosuppressive Activity of Rhazinilam.

Six new monoterpenoid indole alkaloids, kopsinidines C-E (1-3), 11,12-methylenedioxychanofruticosinic acid (4), 12-methoxychanofruticosinic acid (5), and N(4)-methylkopsininate (7), as well as chanofruticosinic acid (6, as a natural product) and 23 known alkaloids, were obtained from the twigs and leaves of Kopsia officinalis. Their structures were characterized by physical data analysis. All isolated compounds were evaluated for their immunosuppressive activity on human T cell proliferation. Rhazinilam (29) significantly inhibited human T cell proliferation activated by anti-CD3/anti-CD28 antibodies (IC50 = 1.0 µM) and alloantigen stimulation (IC50 = 1.1 µM) without obvious cytotoxicity for naïve human T cells and peripheral blood mononuclear cells (0-320 µM). Although it did not affect T cell activation, it induced T cell cycle arrest in the G2/M phase and inhibited proinflammatory cytokine production in activated T cells.

[Expression and significance of P75 neurotrophin receptor in oral squamous cell carcinoma].

PURPOSE: To investigate the expression of P75NTR in oral squamous cell carcinoma and evaluate the possibilities of P75NTR as a prognostic indicator of oral squamous cell carcinoma as well as a marker of cancer stem cell. METHODS: SP immunohistochemical method was used to detect the expressions of tongue squamous cell carcinoma line Tca8113 and 43 surgically resected squamous cell carcinoma tissues. Five peri-carcinoma tissues and 8 normal tissues were selected as control. SPSS16.0 software package was applied for X(2) test. RESULTS: P75NTR was positive in the Tca8113 cell line and located in the cell membrane. Thirty-three cases of the 43 OSCC patients showed positive expression of P75NTR. Para-carcinoma tissues and normal tissues showed negative expression of P75NTR. Positive P75NTR located in the cell membrane and dispersed in the cancer nest, and had a trend of cluster distribution. The expression of P75NTR had a relationship with tumor clinical stage(P<0.05) and lymph node metastasis(P<0.05). CONCLUSIONS: The expression of P75NTR can predict the prognosis of oral squamous cell carcinoma, yet it can not be taken as a marker of cancer stem cell alone. Further study should be taken to investigate the role and mechanism of P75NTR in the development of tumor.