Objective:To discuss the effects of Buzhong Yiqi Decoction medicated serum combined with cisplatin on the expression of Nrf2 and its effects of downstream antioxidant proteins in human pulmonary adenocarcinoma A549/DDP cells.Methods:Totally 60 rats were divided into blank group, low-dosage group, medium-dosage group, and high-dosage group using a random number table method, with 15 rats in each group. The low-, medium-, and high-dosage groups were orally administered with 3.29, 6.57, and 13.13 g/kg Buzhong Yiqi Decoction for gavage, once a day, for 7 days. 1 hour after the last administration, blood was collected from the abdominal aorta to prepare the serum containing Buzhong Yiqi Decoction. A549/DDP cells were divided into 5 groups: blank group (rat serum), model group (rat serum+cisplatin), low-dosage group (low-dosage Buzhong Yiqi Decoction medicated serum+cisplatin), medium-dosage group (medium-dosage Buzhong Yiqi Decoction medicated serum +cisplatin), and high-dosage group (high-dosage Buzhong Yiqi Decoction medicated serum+cisplatin). And 24 h after the Buzhong Yiqi Decoction intervention, CCK-8 method was used to detect the IC 50 of cisplatin in each group. The fluorescence expression intensity of p-Nrf2 in A549/DDP cells of each group was determined by confocal fluorescence localization method. The mRNA relative expression of Nrf2 in A549/DDP cells of each group was detected by RT-qPCR. The relative expressions of Nrf2, p-Nrf2, GPX4, PRX1 and SOD in A549/DDP cells of each group were detected by Western blot. Results:Compared with the model group, the IC 50 of A549/DDP cells to cisplatin decreased in the low-, medium-, and high-dosage groups ( P<0.01); the fluorescence intensity of p-Nrf2 decreased ( P<0.01); the level of Nrf2 mRNA decreased ( P<0.01); the protein expressions of Nrf2, p-Nrf2, SOD, PRX1, and GPX4 were down-regulated ( P<0.01), with the effect being more significant in the medium- and high-dosage groups ( P<0.05). Conclusion:Buzhong Yiqi Decoction medicated serum can improve cisplatin resistance in human pulmonary adenocarcinoma cancer by inhibiting the active expression of Nrf2 in A549/DDP cells and down-regulating the target genes of SOD, PRX1 and GPX4 in vivo.

Objective:To investigate the effects of Buzhong Yiqi Decoction on the expressions of multidrug resistance-related protein (MRP), lung resistance-related protein (LRP), and P-glycoprotein (P-gp) in transplantation tumor of A549 tumor-bearing nude mice.Methods:A549 cells were cultured to establish xenograft models of tumor-bearing nude mice. According to the random number table method, they were divided into blank control group, cisplatin group, cisplatin + Buzhong Yiqi Decoction low-dosage group, cisplatin + Buzhong Yiqi Decoction medium-dosage group, cisplatin + Buzhong Yiqi Decoction high-dosage group. After 25 days of corresponding drug intervention, the mRNA expressions of MRP, LRP and P-gp in transplantation tumors were detected by Real-Time PCR, and Western blot was used to detect the expressions of MRP, LRP and P-gp proteins in xenograft tissues in each group.Results:Compared with blank control group, the mRNA and protein expressions of MRP, LRP and P-gp in cisplatin group were significantly down-regulated ( P<0.05). Compared with cisplatin group, the mRNA and protein expressions of MRP, LRP and P-gp in the cisplatin + Buzhong Yiqi Decoction low-dosage group, cisplatin + Buzhong Yiqi Decoction medium-dosage group, cisplatin+Buzhong Yiqi Decoction high-dosage group decreased ( P<0.05). Conclusion:Buzhong Yiqi Decoction can inhibit the expressions of MRP, LRP and P-gp in transplantation tumor of A549 tumor-bearing nude mice and without dosage dependence.

ObjectiveTo explore the mechanism of Buzhong Yiqitang-containing serum in alleviating the cisplatin resistance in human non-small cell lung cancer （A549/DDP） cells via regulating the nuclear factor E₂-related factor 2 （Nrf2）/reactive oxygen species （ROS） signaling pathway. MethodThe serum containing Buzhong Yiqitang was prepared and A549/DDP cells were cultured and randomly grouped： blank （10% blank serum）， cisplatin （10% blank serum+20 mg·L^-1 cisplatin）， Buzhong Yiqitang （10% Buzhong Yiqitang-containing serum+20 mg·L^-1 cisplatin）， ML385 （10% blank serum+5 μmol·L^-1 ML385+20 mg·L^-1 cisplatin）， Buzhong Yiqitang+ML385 （10% Buzhong Yiqitang-containing serum+5 μmol·L^-1 ML385+20 mg·L^-1 cisplatin）， tertiary butylhydroquinone （TBHQ） （10% blank serum+5 μmol·L^-1 TBHQ+20 mg·L^-1 cisplatin）， and Buzhong Yiqitang+TBHQ （10% Buzhong Yiqitang-containing serum+5 μmol·L^-1 TBHQ+20 mg·L^-1 cisplatin）. The median inhibitory concentration （IC₅₀） of cisplatin in each group was determined by the cell counting kit-8 （CCK-8） method and the resistance index （RI） was calculated. The apoptosis rate was detected by flow cytometry. The ROS content of each group was determined with the DCFH-DA fluorescence probe. Western blot was employed to determine the protein levels of Nrf2， cleaved cysteinyl aspartate-specific protease-3 （cleaved Caspase-3）， cytochrome C （Cyt C）， and B-cell lymphoma-2 （Bcl-2）. ResultCompared with those in the cisplatin group， the IC₅₀ and RI of A549/DDP cells to cisplatin in Buzhong Yiqitang， ML385， and Buzhong Yiqitang+ML385 groups decreased （P˂0.05）. Compared with the blank group， the cisplatin， Buzhong Yiqitang， ML385， and Buzhong Yiqitang+ML385 groups showed increased apoptosis rate of A549/DDP cells （P˂0.05）. Compared with the blank group， cisplatin promoted the expression of Nrf2 （P˂0.05）. Compared with the cisplatin group， Buzhong Yiqitang， ML385， and Buzhong Yiqitang+ML385 inhibited the expression of Nrf2 （P<0.05）， elevated the ROS level （P˂0.05）， up-regulated the protein levels of cleaved Caspase-3 and Cyt C， and down-regulated the protein level of Bcl-2 （P<0.05）， which were the most significant in the Buzhong Yiqitang+ML385 group. Compared with the cisplatin group， the TBHQ group showed increased IC₅₀ and RI of cisplatin （P<0.05）， decreased apoptosis rate of A549/DDP cells （P<0.05）， up-regulated protein levels of Nrf2 and Bcl-2 （P<0.05）， lowered level of ROS （P˂0.05）， and down-regulated protein levels of cleaved Caspase-3 and Cyt C （P<0.05）. Compared with the TBHQ group， Buzhong Yiqitang+TBHQ decreased the IC₅₀ and RI of cisplatin in A549/DDP cells （P<0.05）， increased the apoptosis rate （P<0.05）， down-regulated the protein levels of Nrf2 and Bcl-2 （P<0.05）， increased ROS （P˂0.05）， and up-regulated the protein levels of cleaved Caspase-3 and Cyt C （P<0.05）. ConclusionBuzhong Yiqitang induced apoptosis by inhibiting Nrf2/ROS pathway to alleviate cisplatin resistance in A549/DDP cells.