ABSTRACT
Objective: To explore the effect of Feng-liao-chang-wei-kang (FLCWK) on acute and chronic gastroenteritis, synergistic effect on the growth inhibitory effect with 5-fluorouracil (5-FU) on colorectal cancer and its underlying mechanisms. Methods: In the in vitro study, HT-29 cells were divided into 5-FU alone, FLCWK alone and coadministration groups. The MTT assay was used to analyze the proliferation of HT-29 cells at 24 h. Flow cytometry was used to observe the apoptosis, cycle of colorectal cancer HT-29 cells at 24 h. In the in vivo experiment, The subcutaneous transplantation tumor model of colorectal cancer HT-29-Luc was established with nude mice. All mice were randomly divided into 5-FU alone, FLCWK alone and coadministration groups according to body weight. During administration, the Interactive Video Information System small animal live imaging system was used to monitor the growth of subcutaneous transplantation in nude mice. The model of colitis-associated colorectal cancer (CACC) was established with BALB/c mice. BALB/c mice were randomly divided into the normal control group, the model control group, and the FLCWK group. At the end of the administration, the pathological status was detected by HE staining. Cell apoptosis of tumor tissue tumor and colon tissues were observed by TUNEL staining and TUNEL green fluorescence. The protein expression of Caspase 3, p-STAT3, Bcl-2, Bax and P-gp in tumor tissues tumor and colon tissues were tested by using immunohistochemical assay. Results: FLCWK and 5-FU coadministration suppressed HT-29 cell viability and induced S phase arrest and apoptosis compared to treatment with 5-FU alone. Furthermore, compared to treatment with 5-FU alone, coadministration of FLCWK and 5-FU obviously reduced tumor volume and weight and induced apoptosis through decreasing p-STAT3 and P-gp and increasing Caspase 3 protein expression in a murine xenograft tumor model. Moreover, the result revealed decreased number and size of tumors following FLCWK protective administration, downregulated p-STAT3 and Bcl-2 levels and upregulated Bax and Caspase 3 expression in mice with CACC. Conclusions: FLCWK has synergistic effects with 5-FU on colorectal cancer by suppressing the STAT3 pathway and downregulating P-gp expression. Furthermore, FLCWK administration suppresses CACC tumorigenesis by inhibiting the STAT3 pathway.
ABSTRACT
This study is to investigate the effect and mechanism of puerarin on DNA damage of HaCaT cells induced by UVB. Puerarin pre-treated cells were irradiated with UVB at 30 mJ x cm(-2). Twenty four hours after irradiation, DNA damage was detected by comet assay, ceramide was measured by thin layer chromatography and gas chromatography, intracellular free calcium ion was analyzed by flow cytometry, the phosphorylation level of p38 protein was examined by Western blotting method. Levels of DNA damage, ceramide, free calcium ion and p-p38 protein were elevated in UVB model cells. Contrary to the model group, all indicators above were reduced in all groups pre-treated by puerarin. Puerarin restrains the ceramide accumulation to block downstream p38 MAPK pathway and calcium ion rising, therefore reduces DNA damage in HaCaT cells induced by UVB.