Xiaoaiping improves the general state of rats with malignant ascites secondary to gastric cancer by blocking the TGF-β1 signaling pathway.

Objective: To investigate the effect of Xiaoaiping on the general state of rats with malignant ascites secondary to gastric cancer by blocking the transforming growth factor-β1 (TGF-β1) signaling pathway.

Methods: Fifty healthy Wistar rats were randomly divided into 5 groups, with 10 rats in each group. After successful modeling, 0.2 g/(20 g∙d), 0.4 g/(20 g∙d) and 0.8 g/(20 g∙d) of Xiaoaiping injections were administrated at the low dose group (LDG), medium dose group (MDG) and high dose group (HDG), respectively. The model group (MG) was injected intraperitoneally with the same amount of sterile normal saline for 8 d. Rats in the control group (CG) were healthy without any treatment. The general states (mental state, dietary habits, reactions and body shape) of rats in each group were observed. The abdominal circumference, platelet (PLT) count, white blood cell (WBC) count, serum ferritin (SF), ascites volume, cell survival rate, and expression levels of TGF-β1 signaling pathway (TGF-β1, Smad2) were compared among the groups.

Results: PLT and WBC counts in the MG were lower than those in the CG. Ascites volume, tumor cell survival rate, and SF in the MG were higher than those in the LDG, MDG and HDG (<0.05). Thymus index in the LDG, MDG and HDG were significantly higher than that in the MG (<0.05). There was no significant difference in the spleen indices among the groups (P>0.05). The kidney index, serum creatinine and urea nitrogen levels in LDG, MDG and HDG were significantly lower than those of MG (<0.05). The LDG, MDG and HDG exhibited significantly higher peripheral blood CD4+ cells and CD4+/CD8+, and lower CD8+ level, as compared with the MG (<0.05). The levels of serum interferon γ (IFN-γ), interleukin (IL)-1α, IL-1β, IL-2, IL-4 and tumor necrosis factor-α (TNF-α) in the LDG, MDG and HDG were higher than those in the MG (<0.05). The ascites volume and tumor cell survival rate were decreased sequentially in the LDG, MDG and HDG (<0.05). The MG had higher mRNA levels of TGF-β1 and Smad2 than the CG (<0.05). No statistically significant difference was found in TGF-β1 and Smad2 between the LDG and MG (>0.05).

Conclusion: Xiaoaiping could significantly reduce the ascites volume in rats with gastric cancer, inhibit the production of tumor cells in the abdominal cavity, and improve the general state of rats in a dose-dependent manner. The mechanism may be related to the down-regulation of the mRNA level of TGF-β1 and Smad2.