OBJECTIVETo explore the mechanism of action of Longbixiao Capsule (LBXC, a Chinese herbal preparation) on human prostatic stromal cell cultured in vitro.

METHODSNine Japan rabbits were assigned to 3 groups. The high, low dose group was given LBXC [2.0 g/(kg x d), 1.0 g/(kg x d)] by gastro gavage respectively, while equal volume of normal saline was given by gastrog avage 60 rats in the control group, all twice a day with an infeval of 12 h, for 3 successive days. The serum collected at 3 h after the last gastro gavage was added into cell culture fluid. Rabbit's serum containing LBXC was incubated with the cultured stromal cells, and the levels of cell proliferation and apoptosis were determined using relative techniques as TUNEL, ELISA, and immunocytochemistry. Besides, Real-time RT-PCR was applied to detect the mRNA expressions of TGF-beta1, and Smad7 in the stromal cells.

RESULTSThe cell proliferation showed culture time dependence in all groups. The proliferation in the drug-serum treated groups was lower than that in the control group, and it was lower in the high dose treated group than in the low dose treated group (all P < 0.01). The unfavorable growth did not occur morphologically after being cultured for 48 h and showed insignificant difference between various groups. Cell apoptosis was not found excepting for a few appeared in the high dose treated group (with a little amount of apoptotic cells occurring). After treatment, the expressions of TGF-beta, and Smad7 were lower in the low dose treated group and high dose treated group than in the control group (P < 0.01). There was not statistical difference between the low dose treated group and high dose treated group (P > 0.05).

CONCLUSIONLBXC could reduce the expressions of TGF-beta1, and smad7 mRNA in stromal cells and inhibit the stromal cell proliferation, but its effect on promoting cell apoptosis is unobvious.