RESUMO
ObjectiveTo investigate the protective effect of Guiqi Baizhu prescription combined with oxaliplatin on the intestinal barrier of tumor-bearing mice with gastric cancer by regulating downstream aquaporin 3 （AQP3） and aquaporin 4 （AQP4） through the vasoactive intestinal peptide （VIP）/cyclic adenosine monophosphate （cAMP）/protein kinase A （PKA） signaling pathway. MethodThe gastric cancer cell lines MFC with a density of 1×107/mL were prepared into cell suspension. The tumor-bearing mouse model of gastric cancer was established by inoculating 0.2 mL cell suspension under the right axilla of mice. After successful modeling， mice were randomly divided into 5 groups， namely， model group， oxaliplatin group （10 mg·kg-1）， and high， medium， and low-dose oxaliplatin + Guiqi Baizhu prescription groups （17.68， 8.84， 4.42 g·kg-1）， with 10 mice in each group， and the remaining 10 mice were set as a blank group. Mice in each group were treated with Chinese medicine， oxaliplatin， or normal saline by gavage or intraperitoneal injection for 14 d. The next day after the last dose， blood was taken from the eyeball to separate serum and take colonic samples. Hematoxylin-eosin （HE） staining was used to observe the changes in tissue morphology. The content of D-lactate acid （D-LA） and diamine oxidase （DAO） in the serum was determined by enzyme-linked immunosorbent assay （ELISA）. The mRNA and protein expressions of VIP， cAMP， PKA， AQP3， and AQP4 were detected by Real-time quantitative polymerase chain reaction （Real-time PCR） and Western blot， respectively. ResultCompared with the blank group， the model group showed edema in the colonic submucosa， disordered arrangement of intestinal glands in the mucosal layer， loss of goblet cells， infiltration of inflammatory cells， and villus shedding. However， there were different degrees of improvement in each administration group. As compared with the blank group， the serum levels of DAO and D-LA in the model group were significantly increased （P<0.01）. As compared with the model group， the levels of DAO and D-LA in the high-dose oxaliplatin + Guiqi Baizhu prescription group and the level of D-LA in the medium-dose oxaliplatin + Guiqi Baizhu prescription group were decreased （P<0.05， P<0.01）. As compared with the oxaliplatin group， the levels of D-LA in the high and medium-dose oxaliplatin + Guiqi Baizhu prescription groups were decreased （P<0.05）， and the levels of DAO and D-LA in other administration groups were decreased as well， but the difference had no statistical significance. As compared with the blank group， the mRNA and protein expression levels of VIP， cAMP， PKA， AQP3， and AQP4 in the model group were significantly decreased （P<0.05， P<0.01）. As compared with the model group， the mRNA and protein expression levels of VIP， cAMP， PKA， AQP3， and AQP4 in each administration group were increased， and those in the high-dose oxaliplatin + Guiqi Baizhu prescription group were significantly increased （P<0.05， P<0.01）， while the protein expression level of cAMP in the medium-dose oxaliplatin + Guiqi Baizhu prescription group were increased （P<0.05）. As compared with the oxaliplatin group， the protein expression levels of cAMP in the high-dose oxaliplatin + Guiqi Baizhu prescription group were increased （P<0.05）， and the mRNA and protein expressions of these indexes in the other groups were also increased but the differences were not statistically significant. ConclusionGuiqi Baizhu prescription combined with oxaliplatin can regulate AQP3 and AQP4 through the VIP/cAMP/PKA signaling pathway to protect the intestinal barrier of tumor-bearing mice with gastric cancer.
RESUMO
ObjectiveTo investigate the effect of Guiqi Baizhu prescription （GQBZ） combined with oxaliplatin on the expression of epidermal growth factor receptor （EGFR） and vascular endothelial growth factor receptor-2 （VEGFR2） and angiogenesis in gastric cancer-bearing mice. MethodThe tumor-bearing model of gastric cancer was induced in Kunming mice. The mice were randomly divided into blank group， model group， oxaliplatin group （10 mg·kg-1）， and high- （17.68 g·kg-1）， medium- （8.84 g·kg-1）， and low-dose （4.42 g·kg-1） combination groups （GQBZ combined with oxaliplatin）. After the last administration， the transplanted tumor was collected and the tumor inhibition rate was calculated. Hematoxylin-eosin （HE） staining was used to observe the morphological changes of tumor tissues. Enzyme-linked immunosorbent assay （ELISA） was used to detect the serum content of epidermal growth factor （EGF）， interleukin-8 （IL-8）， and vascular endothelial growth factor （VEGF）. Western blot and immunohistochemistry （IHC） were used to detect the expression of EGFR， phosphorylated EGFR （p-EGFR）， VEGFR2， phosphorylated VEGFR2 （p-VEGFR2）， and platelet-endothelial cell adhesion molecule （CD31）. Real-time fluorescence-based quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of EGFR and VEGFR2. ResultThe tumor weight in the drug intervention groups was significantly lower than that in the model group （P<0.01）. Compared with the oxaliplatin group， the high- and medium-dose combination groups showed reduced tumor weight （P<0.05， P<0.01）. The tumor cells in the model groups were high in cell density and regular in shape， and no clear tissue necrosis was seen. The tumor cell density in the drug intervention groups was reduced， and clear tissue necrosis and large-scale inflammatory cells were visible. Compared with the blank group， the model group and the drug intervention groups showed increased serum levels of EGF， VEGF， and IL-8 （P<0.05， P<0.01）. Compared with the model group， the drug intervention groups showed decreased serum levels of EGF， VEGF， and IL-8 （P<0.01）， reduced protein expression of EGFR， p-EGFR， VEGFR2， p-VEGFR2， and CD31， and declining mRNA expression of EGFR and VEGFR （P<0.01）. Compared with the oxaliplatin group， the high- and medium-dose combination groups showed decreased serum levels of EGF， VEGF， and IL-8 （P<0.05， P<0.01）， reduced protein expression of EGFR， p-EGFR， VEGFR2， p-VEGFR2， and CD31， and dwindled mRNA expression of EGFR and VEGFR2 （P<0.05， P<0.01）. The low-dose combination group showed decreased serum levels of EGF， VEGF， and IL-8， reduced protein expression of EGFR， p-EGFR， VEGFR2， p-VEGFR2， and CD31， and dwindled mRNA expression of EGFR and VEGFR2， but the difference was not statistically significant. ConclusionGQBZ combined with oxaliplatin can inhibit the growth and angiogenesis of tumor tissues in gastric cancer-bearing mice by affecting the expression of EGFR and VEGFR2.