BACKGROUND:Knee osteoarthritis(KOA)is a common chronic inflammatory disease that causes damage to joint cartilage and surrounding tissues.Immune cells play an important role in the immune-inflammatory response in knee osteoarthritis,but the specific mechanisms involved are still not fully understood. OBJECTIVE:To evaluate the potential causal relationship between 731 immune cell phenotypes and the risk of knee osteoarthritis using Mendelian randomization. METHODS:Summary statistics of genome-wide association studies(GWAS)for 731 immune cell phenotypes(from GCST0001391 to GCST0002121)obtained from the GWAS catalog and GWAS data for knee osteoarthritis from the IEUGWAS database(ebi-a-GCST007090)were used.Inverse variance-weighted method,MR-Egger regression,weighted median method,weighted mode method,and simple mode method were employed to investigate the causal relationship between immune cells and knee osteoarthritis.Sensitivity analyses were conducted to assess the reliability of the Mendelian randomization results.Reverse Mendelian randomization analysis was also performed using the same methods. RESULTS AND CONCLUSION:The forward MR analysis indicated significant causal relationships(FDR<0.20)between knee osteoarthritis and four immune cell phenotypes,namely CD27 on CD24+CD27+in B cells(OR=1.026,P=0.000 26,Pfdr=0.18),CD33 on CD33dim HLA DR-in myeloid cells(OR=1.014,P=0.000 50,Pfdr=0.18),and CD45RA+CD28-CD8br%CD8br in Treg cells(OR=1.001,P=0.000 78,Pfdr=0.18),and PDL-1 on monocytes in mononuclear cells(OR=0.952,P=0.000 98,Pfdr=0.18).These immune cell phenotypes showed direct positive or negative causal associations with the risk of knee osteoarthritis.Reverse Mendelian randomization analysis revealed no significant causal relationships(FDR<0.20)between knee osteoarthritis as exposure and any of the 731 immune cell phenotypes.The results of sensitivity analysis show that the P-values of the Cochran's Q test and the MR-Egger regression method for bidirectional Mendelian randomization were both greater than 0.05,indicating that there is no significant heterogeneity and pleiotropy in the causal effect analysis between immune cell phenotypes and knee osteoarthritis.To conclude,there may be four potential causal relationships between immune cell phenotypes,such as CD27 on CD24+CD27+cells,CD33 on CD33dim HLA DR-cells,CD45RA+CD28-CD8br%CD8br cells,and PDL-1 on monocytes,and knee osteoarthritis.These findings provide valuable clues for studying the biological mechanisms of knee osteoarthritis and exploring early prevention and treatment strategies.They also offer new directions for the development of intervention drugs.

BACKGROUND:Liuwei Dihuang Wan takes"three tonifying and three reducing effects"as its compatibility feature to nourish yin and tonify the kidneys,while Zuogui Wan takes"seeking yin in yang"as its compatibility feature to nourish yin and tonify the kidneys by promoting yang.Both of them belong to the same method of nourishing yin and tonifying the kidneys,and have better curative effects at the symptomatic and cellular molecular levels. OBJECTIVE:To observe the effects of Liuwei Dihuang Wan and Zuogui Wan in bone metabolism,and to explore their mechanism of action in the osteoprotegerin(OPG)/receptor activator of nuclear factor-κB ligand(RANKL)osteoblastic pathway. METHODS:Thirty-two Sprague-Dawley rats were randomized into model,Liuwei Dihuang Wan,Zuogui Wan,and sham operation group,with eight rats in each group.Osteoporosis models were prepared using removal of both ovaries in the first three groups.Starting at 30 days postoperatively,rats in the Liuwei Dihuang Wan group were gavaged with Liuwei Dihuang Wan 1.125 g/kg/d;rats in the Zuoqui Wan group were gavaged with Zuogui Wan 2.25 g/kg/d;and rats in the sham operation group and the model group were gavaged with saline 10 mL/kg/d.After 12 weeks of gavage,the rat tibia was taken to measure bone mineral density.The serum levels of estrogen,bone alkaline phosphatase,and cAMP/cGMP were measured using ELISA,and the expression of OPG/RANKL in the femur was detected using western blot. RESULTS AND CONCLUSION:Compared with the sham operation group,the model group showed a decrease in bone mineral density and levels of estrogen and bone alkaline phosphatase(P＜0.05)and an increase in cAMP/cGMP level(P＜0.05).Compared with the model group,the Liuwei Dihuang Wan group and the Zuogui Wan group significantly increased bone mineral density(P＜0.05)and bone alkaline phosphatase levels(P＜0.05);the Zuogui Wan group significantly decreased cAMP/cGMP levels(P＜0.05)and upregulated OPG expression(P＜0.05);the Liuwei Dihuang Wan group upregulated OPG expression and downregulated RANKL expression(P＜0.05);and both groups were unable to significantly increase estrogen levels(P＞0.05).To conclude,Zuogui Wan,which seeks yin from yang,can effectively increase the expression of OPG but cannot downregulate the expression of RANKL.However,Liuwei Dihuang Wan,which has three tonifying and three reducing effects,can bidirectionally regulate the expression of OPG and RANKL.This result suggests that Liuwei Dihuang Wan can significantly inhibit osteoclastic function compared with Zuogui Wan,and further research is needed to verify this conclusion.

BACKGROUND:Flap transplantation technique is a commonly used surgical procedure for the treatment of severe tissue defects,but postoperative flap necrosis is easily triggered by ischemia-reperfusion injury.Therefore,it is still an important research topic to improve the survival rate of transplanted flaps. OBJECTIVE:To review the pathogenesis and latest treatment progress of flap ischemia-reperfusion injury. METHODS:CNKI,WanFang Database and PubMed database were searched for relevant literature published from 2014 to 2024.The search terms used were"flap,ischemia-reperfusion injury,inflammatory response,oxidative stress,Ca2+overload,apoptosis,mesenchymal stem cells,platelet-rich plasma,signaling pathways,shock wave,pretreatment"in Chinese and English.After elimination of irrelevant literature,poor quality and obsolete literature,77 documents were finally included for review. RESULTS AND CONCLUSION:Flap ischemia/reperfusion injury may be related to pathological factors such as inflammatory response,oxidative stress response,Ca2+overload,and apoptosis,which can cause apoptosis of vascular endothelial cells,vascular damage and microcirculation disorders in the flap,and eventually lead to flap necrosis.Studies have found that mesenchymal stem cell transplantation,platelet-rich plasma,signaling pathway modulators,shock waves,and pretreatment can alleviate flap ischemia/reperfusion injuries from different aspects and to varying degrees,and reduce the necrosis rate and necrosis area of the grafted flap.Although there are many therapeutic methods for skin flap ischemia/reperfusion injury,a unified and effective therapeutic method has not yet been developed in the clinic,and the advantages and disadvantages of various therapeutic methods have not yet been compared.Most of the studies remain in the stage of animal experiments,rarely involving clinical observations.Therefore,a lot of research is required in the future to gradually move from animal experiments to the clinic in order to better serve the clinic.

BACKGROUND:Osteoporotic fracture is the most serious complication of osteoporosis.Previous studies have demonstrated that gut microbiota has a regulatory effect on skeletal tissue and that gut microbiota has an important relationship with osteoporotic fracture,but the causal relationship between the two is unclear. OBJECTIVE:To explore the causal relationship between gut microbiota and osteoporotic fractures using Mendelian randomization method. METHODS:The genome-wide association study(GWAS)datasets of gut microbiota and osteoporotic fracture were obtained from the IEU Open GWAS database and the Finnish database R9,respectively.Using gut microbiota as the exposure factor and osteoporotic fracture as the outcome variable,Mendelian randomization analyses with random-effects inverse variance weighted,MR-Egger regression,weighted median,simple model,and weighted model methods were performed to assess whether there is a causal relationship between gut microbiota and osteoporotic fracture.Sensitivity analyses were performed to test the reliability and robustness of the results.Reverse Mendelian randomization analyses were performed to further validate the causal relationship identified in the forward Mendelian randomization analyses. RESULTS AND CONCLUSION:The results of this Mendelian randomization analysis indicated a causal relationship between gut microbiota and osteoporotic fracture.Elevated abundance of Actinomycetales[odds ratio(OR)=1.562,95%confidence interval(CI):1.027-2.375,P=0.037),Actinomycetaceae(OR=1.561,95%CI:1.027-2.374,P=0.037),Actinomyces(OR=1.544,95%CI:1.130-2.110,P=0.006),Butyricicoccus(OR=1.781,95%CI:1.194-2.657,P=0.005),Coprococcus 2(OR=1.550,95%CI:1.068-2.251,P=0.021),Family ⅩⅢ UCG-001(OR=1.473,95%CI:1.001-2.168,P=0.049),Methanobrevibacter(OR=1.274,95%CI:1.001-1.621,P=0.049),and Roseburia(OR=1.429,95%CI:1.015-2.013,P=0.041)would increase the risk of osteoporotic fractures in patients.Elevated abundance of Bacteroidia(OR=0.660,95%CI:0.455-0.959,P=0.029),Bacteroidales(OR=0.660,95%CI:0.455-0.959,P=0.029),Christensenellacea(OR=0.725,95%CI:0.529-0.995,P=0.047),Ruminococcaceae(OR=0.643,95%CI:0.443-0.933,P=0.020),Enterorhabdus(OR=0.558,95%CI:0.395-0.788,P=0.001),Eubacterium rectale group(OR=0.631,95%CI:0.435-0.916,P=0.016),Lachnospiraceae UCG008(OR=0.738,95%CI:0.546-0.998,P=0.048),and Ruminiclostridium 9(OR=0.492,95%CI:0.324-0.746,P=0.001)would reduce the risk of osteoporotic fractures in patients.We identified 16 gut microbiota associated with osteoporotic fracture by the Mendelian randomization method.That is,using gut microbiota as the exposure factor and osteoporotic fracture as the outcome variable,eight gut microbiota showed positive causal associations with osteoporotic fracture and another eight gut microbiota showed negative causal associations with osteoporotic fracture.The results of this study not only identify new biomarkers for the early prediction of osteoporotic fracture and potential therapeutic targets in clinical practice,but also provide an experimental basis and theoretical basis for the study of improving the occurrence and prognosis of osteoporotic fracture through gut microbiota in bone tissue engineering.

BACKGROUND:Osteosarcoma has a complex pathogenesis and a poor prognosis.While advancements in medical technology have led to some improvements in the 5-year survival rate,substantial progress in its treatment has not yet been achieved. OBJECTIVE:To screen key molecular markers in osteosarcoma,analyze their relationship with osteosarcoma treatment drugs,and explore the potential disease mechanisms of osteosarcoma at the molecular level. METHODS:GSE99671 and GSE284259(miRNA)datasets were obtained from the Gene Expression Omnibus database.Differential gene expression analysis and Weighted Gene Co-expression Network Analysis(WGCNA)on GSE99671 were performed.Functional enrichment analysis was conducted using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes separately for the differentially expressed genes and the module genes with the highest positive correlation to the disease.The intersection of these module genes and differentially expressed genes was taken as key genes.A Protein-Protein Interaction network was constructed,and correlation analysis on the key genes was performed using CytoScape software,and hub genes were identified.Hub genes were externally validated using the GSE28425 dataset and text validation was conducted.The drug sensitivity of hub genes was analyzed using the CellMiner database,with a threshold of absolute value of correlation coefficient|R|>0.3 and P<0.05. RESULTS AND CONCLUSION:(1)Differential gene expression analysis identified 529 differentially expressed genes,comprising 177 upregulated and 352 downregulated genes.WGCNA analysis yielded a total of 592 genes with the highest correlation to osteosarcoma.(2)Gene Ontology enrichment results indicated that the development of osteosarcoma may be associated with extracellular matrix,bone cell differentiation and development,human immune regulation,and collagen synthesis and degradation.Kyoto Encyclopedia of Genes and Genomes enrichment results showed the involvement of pathways such as PI3K-Akt signaling pathway,focal adhesion signaling pathway,and immune response in the onset of osteosarcoma.(3)The intersection analysis revealed a total of 59 key genes.Through Protein-Protein Interaction network analysis,8 hub genes were selected,which were LUM,PLOD1,PLOD2,MMP14,COL11A1,THBS2,LEPRE1,and TGFB1,all of which were upregulated.(4)External validation revealed significantly downregulated miRNAs that regulate the hub genes,with hsa-miR-144-3p and hsa-miR-150-5p showing the most significant downregulation.Text validation results demonstrated that the expression of hub genes was consistent with previous research.(5)Drug sensitivity analysis indicated a negative correlation between the activity of methotrexate,6-mercaptopurine,and pazopanib with the mRNA expression of PLOD1,PLOD2,and MMP14.Moreover,zoledronic acid and lapatinib showed a positive correlation with the mRNA expression of PLOD1,LUM,MMP14,PLOD2,and TGFB1.This suggests that zoledronic acid and lapatinib may be potential therapeutic drugs for osteosarcoma,but further validation is required through additional basic experiments and clinical studies.

BACKGROUND:In recent years,numerous studies have shown that autophagy and mitophagy play an important role in the regulation of bone metabolism.Under non-physiological conditions,mitophagy breaks the balance of bone metabolism and triggers metabolism disorders,which affect osteoblasts,osteoclasts,osteocytes,chondrocytes,bone marrow mesenchymal stem cells,etc. OBJECTIVE:To summarize the mechanism of mitophagy in regulating bone metabolic diseases and its application in clinical treatment. METHODS:PubMed,Web of Science,CNKI,WanFang and VIP databases were searched by computer using the keywords of"mitophagy,bone metabolism,osteoblasts,osteoclasts,osteocytes,chondrocytes,bone marrow mesenchymal stem cells"in English and Chinese.The search time was from 2008 to 2023.According to the inclusion criteria,90 articles were finally included for review and analysis. RESULTS AND CONCLUSION:Mitophagy promotes the generation of osteoblasts through SIRT1,PINK1/Parkin,FOXO3 and PI3K signaling pathways,while inhibiting osteoclast function through PINK1/Parkin and SIRT1 signaling pathways.Mitophagy leads to bone loss by increasing calcium phosphate particles and tissue protein kinase K in bone tissue.Mitophagy improves the function of chondrocytes through PINK1/Parkin,PI3K/AKT/mTOR and AMPK signaling pathways.Modulation of mitophagy shows great potential in the treatment of bone diseases,but there are still some issues to be further explored,such as different stages of drug-activated mitophagy,and the regulatory mechanisms of different signaling pathways.

OBJECTIVE To explore the clinical effect and safety of nicorandil combined with different doses of tirofiban in the treatment of elderly patients with acute ST-segment elevation myocardial infarction （STEMI）. METHODS A total of 162 elderly patients with STEMI admitted to our hospital from June 1， 2022 to June 1， 2024 were retrospectively enrolled. All patients received percutaneous coronary intervention （PCI） and conventional treatment of STEMI， and used nicorandil （5 mg each time， tid） and tirofiban. According to the use of tirofiban， the patients were divided into conventional-dose group （n＝104） and half-dose group （n＝58）. Patients in the conventional-dose group received an intracoronary injection of 10 μg/kg tirofiban， followed by intravenous infusion of 0.1 μg/（kg·min） for 48 h； patients in the half-dose group received an intracoronary injection of 5 μg/kg tirofiban， followed by intravenous infusion of 0.05 μg/（kg·min） for 48 h. Related indexes of PCI （the proportion of patients with grade 3 of thrombolysis in myocardial infarction， no reflow in infarct related artery， percentage decrease in total ST-segment elevation ＞50% on electrocardiogram 2 hours after PCI）， cardiac function parameters before and after treatment （troponin I， N-terminal pro-brain natriuretic peptide contents and left ventricular ejection fraction）， bleeding events during treatment （gingival bleeding， epistaxis， mucosal bleeding， gastrointestinal bleeding） and other adverse events （all-cause death， non-fatal reinfarction， hypotension， ventricular fibrillation， acute heart failure） were compared between 2 groups. RESULTS There were no significant differences in related parameters of PCI， cardiac function parameters after treatment， the incidences of gingival bleeding， epistaxis and gastrointestinal bleeding， the total incidence of bleeding events， or the incidence of other adverse events during treatment between 2 groups （P＞0.05）， but the incidence of mucosal bleeding in the conventional-dose group was significantly higher than the half-dose group （P＜0.05）. CONCLUSIONS The clinical effect of nicorandil combined with half-dose tirofiban in the treatment of elderly patients with acute STEMI is comparable to that of nicorandil combined with conventional dose of tirofiban， but the mucosal bleeding risk of the former is lower than that of the latter. Therefore， patients at risk of mucosal bleeding are more suitable to use the previous regimen.

ObjectiveTo explore the molecular mechanism of Buzhong Yiqitang in attenuating cisplatin resistance of non-small cell lung cancer （NSCLC） cells （A549/DDP） by regulating endoplasmic reticulum stress （ERS） via the nuclear factor E₂-related factor 2 （Nrf2）/reactive oxygen species （ROS）/double-stranded RNA-activated protein kinase R （PKR）-like endoplasmic reticulum kinase （PERK）/CCAAT enhancer-binding protein homologous protein （CHOP） signaling pathway. MethodsSprague Dawley （SD） rats were used to prepare blank serum and Buzhong Yiqitang-containing serum samples， and A549/DDP cells were sub-cultured and randomly allocated into 9 groups： Blank （10% blank rat serum medium）， model （10% blank rat serum medium+20 mg·L^-1 cisplatin）， traditional Chinese medicine（TCM） （10% Buzhong Yiqitang-containing rat serum medium+20 mg·L^-1 cisplatin）， TBHQ （10% blank rat serum medium+5 μmol·L^-1 TBHQ+20 mg·L^-1 cisplatin）， TBHQ+TCM （10% Buzhong Yiqitang-containing rat serum medium+5 μmol·L^-1 TBHQ+20 mg·L^-1 cisplatin）， NAC （10% blank rat serum medium+600 μmol·L^-1 NAC+20 mg·L^-1 cisplatin）， NAC+TCM （10% Buzhong Yiqitang-containing rat serum medium+600 μmol·L^-1 NAC+20 mg·L^-1 cisplatin）， Salubrinal （10% blank rat serum medium+20 μmol·L^-1 Salubrinal+20 mg·L^-1 cisplatin）， and Salubrinal+TCM （10% Buzhong Yiqitang-containing rat serum medium+20 μmol·L^-1 Salubrinal+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. The ROS level was detected by flow cytometry. The ultrastructure of endoplasmic reticulum （ER） was observed by transmission electron microscopy. Western blot was employed to determine the protein levels of Nrf2， phosphorylated （p）-Nrf2， CHOP， PERK， p-PERK， eukaryotic translation initiation factor 2α （eIF2α）， p-eIF2α， and activated transcription factor 4 （ATF4）. The fluorescence intensity of CHOP and p-PERK was detected by confocal fluorescence localization. ResultsCompared with the model group， the TCM group showed a decrease in IC₅₀ of cisplatin in A549/DDP cells （P<0.01）. TBHQ， NAC， and Salubrinal groups showed increases in IC₅₀ of cisplatin in A549/DDP cells （P<0.01）. TCM combined with TBHQ， NAC， and Salubrinal reduced the IC₅₀ （P<0.01）. Compared with that in the blank group， the ROS level in the model group elevated （P<0.01）. Compared with that in the model group， the ROS level in the TCM group elevated （P<0.01）. The ROS levels in the TBHQ， NAC， and Salubrinal groups were lower than that in the model group （P<0.01）. The combinations of TBHQ， NAC， and Salubrinal with TCM raised the ROS levels of A549/DDP cells （P<0.01）. A flat saclike and neatly arranged ER structure was observed in the blank group， and slight expansion of ER was observed in the model group. Significant expansion of ER was observed in the TCM group. The expansion of ER was not obvious in the TBHQ， NAC， and Salubrinal groups but significant after TBHQ， NAC， and Salubrinal were combined with TCM. CHOP and p-PERK showed higher fluorescence intensity in the model group than in the blank group （P<0.01）， and the fluorescence signal intensity in the TCM group was higher than that in the model group （P<0.01）. The fluorescence intensity in the TBHQ， NAC， and Salubrinal groups was lower than that in the model group （P<0.01）. The fluorescence intensity in the groups of TBHQ， NAC， and Salubrinal combined with TCM was higher than that in corresponding groups without TCM （P<0.01）. Compared with those in the blank group， the expression levels of Nrf2 and p-Nrf2 were up-regulated in the model group （P<0.05）. Compared with the model group， the TCM group showed down-regulated expression levels of Nrf2 and p-Nrf2 （P<0.05）. TBHQ， NAC， and Salubrinal increased the expression levels of Nrf2 and p-Nrf2 （P<0.05）， while their combinations with TCM decreased the expression levels of Nrf2 and p-Nrf2 compared with the corresponding groups without TCM （P<0.01）. There were no significant differences in the expression levels of PERK and eIF2α between groups. The expression levels of CHOP， p-PERK/PERK， p-eIF2α/eIF2α， and ATF4 were up-regulated in the model group compared with those in the blank group （P<0.05）. Compared with the model group， the TCM group showed up-regulated expression levels of CHOP， p-PERK/PERK， p-eIF2α/eIF2α， and ATF4 （P<0.05）， while the TBHQ， NAC， and Salubrinal groups showed down-regulated expression levels （P<0.05）. The groups of TBHQ， NAC， and Salubrinal combined with TCM had higher expression levels than the groups without TCM （P<0.01）. ConclusionBuzhong Yiqitang regulates ERS via the Nrf2/ROS/PERK/CHOP signaling pathway to attenuate cisplatin resistance in NSCLC.

ObjectiveTo explore the molecular mechanism of Buzhong Yiqitang in attenuating cisplatin resistance in non-small cell lung cancer （NSCLC） by inducing ferroptosis via poly（rC）-binding protein 1 （PCBP1）. MethodsThe serum containing Buzhong Yiqitang was prepared and cisplatin-resistant human non-small cell lung cancer （NSCLC） cells （A549/DDP） were cultured and randomly grouped as follows： Blank （10% blank serum）， model （10% blank serum+20 mg·L^-1 cisplatin）， Buzhong Yiqitang （10% serum containing Buzhong Yiqitang+20 mg·L^-1 cisplatin）， Fe-1 （10% blank serum+20 mg·L^-1 cisplatin+5 μmol·L^-1 Fe-1）， and Buzhong Yiqitang+Fe-1 （10% serum containing Buzhong Yiqitang+20 mg·L^-1 cisplatin+5 μmol·L^-1 Fe-1）. Firstly， PCR Array was used to screen ferroptosis-related genes regulated by Buzhong Yiqitang， and PCBP1 was identified as the target for studying the attenuation of cisplatin resistance by Buzhong Yiqitang. Subsequently， 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 ultrastructure of A549/DDP cells in each group was observed by transmission electron microscopy. The protein levels of PCBP1 and glutathione peroxidase 4 （GPX4） were determined by Western blot. The lipid reactive oxygen species （ROS） content in each group was determined by the C11-BODIRY 581/591 fluorescence probe. The ferrous ion assay kit was used to measure the ferrous ion content in each group. The malondialdehyde （MDA） assay kit was used to determine the MDA content in each group. ResultsCompared with model group， the IC₅₀ of cisplatin and the RI of A549/DDP cells decreased in the Buzhong Yiqitang group （P<0.05） but increased in the Fe-1 group （P<0.05）. The IC₅₀ of cisplatin and the RI of A549/DDP cells in the Buzhong Yiqitang+Fe-1 group were lower than those in the Fe-1 group （P<0.05）. Compared with the model group， the Buzhong Yiqitang group showed obvious mitochondrial ferroptosis， while the mitochondrial damage became less obvious after Fe-1 treatment. Compared with that in the Fe-1 group， the mitochondrial ferroptosis was aggravated after the intervention with Buzhong Yiqitang. Compared with blank group， the model group showed down-regulated expression levels of PCBP1 and GPX4 （P<0.05） and increased content of lipid ROS， ferrous ions， and MDA （P<0.05） in A549/DDP cells. Compared with model group， the Buzhong Yiqitang group showed down-regulated expression levels of PCBP1 and GPX4 （P<0.05） and increased content of lipid ROS， ferrous ions， and MDA （P<0.05）， while the Fe-1 group showed up-regulated expression levels of PCBP1 and GPX4 （P<0.05） and reduced content of lipid ROS， ferrous ions， and MDA （P<0.05）. Compared with the Fe-1 group， the Buzhong Yiqitang+Fe-1 group showed down-regulated expression levels of PCBP1 and GPX4 and increased content of lipid ROS， ferrous ions， and MDA （P<0.05）. ConclusionBuzhong Yiqitang attenuated cisplatin resistance in NSCLC by regulating PCBP1 to induce ferroptosis.

ObjectiveTo investigate the mechanism of Buzhong Yiqitang in attenuating cisplatin resistance in non-small cell lung cancer by observing the effects of Buzhong Yiqitang on endoplasmic reticulum stress-related molecules in human lung adenocarcinoma cells （A549） and cisplatin-resistant cells in human lung adenocarcinoma cells （A549/DDP） via the nuclear factor E₂-related factor 2（Nrf2）/reactive oxygen species（ROS） pathway. MethodsThe serum containing Buzhong Yiqitang was prepared and A549 cells and A549/DDP cells were cultured. The cells were randomized into groups A （A549 cells+blank serum）， B （A549 cells+20 mg·L^-1 cisplatin+blank serum）， C （A549 cells+20 mg·L^-1 cisplatin+10% Buzhong Yiqitang-containing serum）， D （A549/DDP cells+blank serum）， E （A549/DDP cells+20 mg·L^-1 cisplatin+blank serum）， and F （A549/DDP cells+20 mg·L^-1 cisplatin+10% Buzhong Yiqitang-containing serum）. The cell counting kit-8 （CCK-8） method was used to detect the half maximal inhibitory concentration （IC₅₀） of cisplatin. The protein levels of Nrf2 and p-Nrf2 were determined by Western blotting. The DCFH-DA fluorescent probe was used to measure the content of reactive oxygen species （ROS） in each group. The protein levels of glucose-regulated protein 78 （GRP78）， activated transcription factor 6 （ATF6）， and C/EBP-homologous protein （CHOP） were determined by Western blot. ResultsCompared with group B， group C showed a reduction in IC₅₀ of cisplatin （P<0.05）， which held true in group E compared with group F （P<0.05）. Moreover， the IC₅₀ of cisplatin to A549/DDP cells was higher than that to A549 cells before and after Buzhong Yiqitang intervention （P<0.05）. Compared with group A， group B showed up-regulated protein levels of Nrf2 and p-Nrf2 （P<0.05）. Compared with group B， group C showed down-regulated protein levels of Nrf2 and p-Nrf2 （P<0.05）. Compared with group D， group E showed up-regulated protein levels of Nrf2 and p-Nrf2 （P<0.05）， which， however， were significantly down-regulated in group F （P<0.05）. The ROS content and the protein levels of GRP78， ATF6， and CHOP followed a descending trend of group C > group B > group A in A549 cells and group F > group E > group D in A549/DDP cells （P<0.05）. Moreover， the ROS content and the protein levels of GRP78， ATF6， and CHOP in A549 cells were higher than those in A549/DDP cells before and after Buzhong Yiqitang intervention （P<0.05）. ConclusionBuzhong Yiqitang may regulate endoplasmic reticulum stress via the Nrf2/ROS pathway to attenuate cisplatin resistance in non-small cell lung cancer.