Baohuoside-1 inhibits activated T cell proliferation at G(1)-S phase transition.
BACKGROUND
The effect of baohuoside-1 (B1), a novel flavonoid, on cell proliferation and the cell cycle was evaluated in this study.


METHODS
The antiproliferative properties of B1 were evaluated by proliferation assay. Western blotting and flow cytometric analysis were employed to investigate the expression of cyclins and cyclin-dependent kinase proteins.


RESULTS
The major findings were (1) B1 effectively inhibited the cell proliferation activated by mitogenic antigen, with a 50% inhibitory concentration in low muM and in a dose- and time-dependent manner. (2) B1 resulted in G(1)-S phase cells arrest. (3) It down-regulated the expression of cyclin A, D and p33 cyclin-dependent kinase-2 (p33cdk2) proteins. (4) B1 suppressed the growth of several tumor cell lines. (5) B1 prevented rat heart allograft rejection in vivo.


CONCLUSIONS
B1 immunosuppression of mitogen-activated T cell proliferation occurs in G(1)-S transition. It may be associated with the expression of cyclin A, D and p33cdk2 proteins. B1 prevents rat heart allograft rejection in vivo. The mechanism of B1 is different from tacrolimus and sirolimus.
Ma
Anlun
A
Laboratory of Experimental Surgery, Centre de recherche du CHUM, Hôpital Notre-Dame, Université de Montréal, Montreal, Quebec, Canada H2L 2W5.
Qi
Shijie
S
Xu
Dasheng
D
Daloze
Pierre
P
Chen
Huifang
H
D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D019925:Cyclin A / Q000378:metabolism; D056741:Cyclin D; D051357:Cyclin-Dependent Kinase 2 / Q000378:metabolism; D016213:Cyclins / Q000378:metabolism; D015536:Down-Regulation; D005419:Flavonoids / Q000494:pharmacology* / Q000627:therapeutic use; D016193:G1 Phase / Q000187:drug effects; D006084:Graft Rejection / Q000517:prevention & control; D016027:Heart Transplantation; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects*; D051381:Rats; D011917:Rats, Inbred Lew; D016196:S Phase / Q000187:drug effects; D013601:T-Lymphocytes / Q000187:drug effects* / Q000502:physiology
D019925:Cyclin A; D056741:Cyclin D; D016213:Cyclins; D005419:Flavonoids; C060988:baohuoside I; D051357:Cyclin-Dependent Kinase 2