This study explores the role and underlying molecular mechanisms of fucoidan sulfate(FPS) in regulating heme oxygenase-1(Hmox1)-mediated ferroptosis to ameliorate myocardial injury in diabetic cardiomyopathy(DCM) through in vivo and in vitro experiments and network pharmacology analysis. In vivo, a DCM rat model was established using a combination of "high-fat diet feeding + two low-dose streptozotocin(STZ) intraperitoneal injections". The rats were randomly divided into four groups: normal, model, FPS, and dapagliflozin(Dapa) groups. In vitro, a cellular model was created by inducing rat cardiomyocytes(H9c2 cells) with high glucose(HG), using zinc protoporphyrin(ZnPP), an Hmox1 inhibitor, as the positive control. An automatic biochemical analyzer was used to measure blood glucose(BG), serum aspartate aminotransferase(AST), serum lactate dehydrogenase(LDH), and serum creatine kinase-MB(CK-MB) levels. Echocardiography was used to assess rat cardiac function, including ejection fraction(EF) and fractional shortening(FS). Pathological staining was performed to observe myocardial morphology and fibrotic characteristics. DCFH-DA fluorescence probe was used to detect reactive oxygen species(ROS) levels in myocardial tissue. Specific assay kits were used to measure serum brain natriuretic peptide(BNP), myocardial Fe~(2+), and malondialdehyde(MDA) levels. Western blot(WB) was used to detect the expression levels of myosin heavy chain 7B(MYH7B), natriuretic peptide A(NPPA), collagens type Ⅰ(Col-Ⅰ), α-smooth muscle actin(α-SMA), ferritin heavy chain 1(FTH1), solute carrier family 7 member 11(SLC7A11), glutathione peroxidase 4(GPX4), 4-hydroxy-2-nonenal(4-HNE), and Hmox1. Immunohistochemistry(IHC) was used to examine Hmox1 protein expression patterns. FerroOrange and Highly Sensitive DCFH-DA fluorescence probes were used to detect intracellular Fe~(2+) and ROS levels. Transmission electron microscopy was used to observe changes in mitochondrial morphology. In network pharmacology, FPS targets were identified through the PubChem database and PharmMapper platform. DCM-related targets were integrated from OMIM, GeneCards, and DisGeNET databases, while ferroptosis-related targets were obtained from the FerrDb database. A protein-protein interaction(PPI) network was constructed for the intersection of these targets using STRING 11.0, and core targets were screened with Cytoscape 3.9.0. Molecular docking analysis was conducted using AutoDock and PyMOL 2.5. In vivo results showed that FPS significantly reduced AST, LDH, CK-MB, and BNP levels in DCM model rats, improved cardiac function, decreased the expression of myocardial injury proteins(MYH7B, NPPA, Col-Ⅰ, and α-SMA), alleviated myocardial hypertrophy and fibrosis, and reduced Fe~(2+), ROS, and MDA levels in myocardial tissue. Furthermore, FPS regulated the expression of ferroptosis-related markers(Hmox1, FTH1, SLC7A11, GPX4, and 4-HNE) to varying degrees. Network pharmacology results revealed 313 potential targets for FPS, 1 125 targets for DCM, and 14 common targets among FPS, DCM, and FerrDb. Hmox1 was identified as a key target, with FPS showing high docking activity with Hmox1. In vitro results demonstrated that FPS restored the expression levels of ferroptosis-related proteins, reduced intracellular Fe~(2+) and ROS levels, and alleviated mitochondrial structural damage in cardiomyocytes. In conclusion, FPS improves myocardial injury in DCM, with its underlying mechanism potentially involving the regulation of Hmox1 to inhibit ferroptosis. This study provides pharmacological evidence supporting the therapeutic potential of FPS for DCM-induced myocardial injury.
Animals ; Ferroptosis/drug effects* ; Rats ; Diabetic Cardiomyopathies/physiopathology* ; Male ; Rats, Sprague-Dawley ; Polysaccharides/pharmacology* ; Heme Oxygenase-1/genetics* ; Myocytes, Cardiac/metabolism* ; Myocardium/pathology* ; Humans ; Cell Line ; Heme Oxygenase (Decyclizing)

This study aimed to explore the mechanisms and molecular targets of total flavones of Abelmoschus manihot(TFA) plus empagliflozin(EM) in attenuating diabetic tubulopathy(DT) by targeting mitochondrial homeostasis and pyroptosis-apoptosis-necroptosis(PANoptosis). In the in vivo study, the authors established the DT rat models through a combination of uninephrectomy, administration of streptozotocin via intraperitoneal injections, and exposure to a high-fat diet. Following modeling successfully, the DT rat models received either TFA, EM, TFA+EM, or saline(as a vehicle) by gavage for eight weeks, respectively. In the in vitro study, the authors subjected the NRK52E cells with or without knock-down Z-DNA binding protein 1(ZBP1) to a high-glucose(HG) environment and various treatments including TFA, EM, and TFA+EM. In the in vivo and in vitro studies, The authors investigated the relative characteristics of renal tubular injury and renal tubular epithelial cells damage induced by reactive oxygen species(ROS), analyzed the relative characteristics of renal tubular PANoptosis and ZBP1-mediatted PANoptosis in renal tubular epithelial cells, and compared the relative characteristics of the protein expression levels of marked molecules of mitochondrial fission in the kidneys and mitochondrial homeostasis in renal tubular epithelial cells, respectively. Furthermore, in the network pharmacology study, the authors predicted and screened targets of TFA and EM using HERB and SwissTargetPrediction databases; The screened chemical constituents and targets of TFA and EM were constructed the relative network using Cytoscape 3.7.2 network graphics software; The relative targets of DT were integrated using OMIM and GeneCards databases; The intersecting targets of TFA, EM, and DT were enriched and analyzed signaling pathways by Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG) software using DAVID database. In vivo study results showed that TFA+EM could improve renal tubular injury, the protein expression levels and characteristics of key signaling molecules in PANoptosis pathway in the kidneys, and the protein expression levels of marked molecules of mitochondrial fission in the kidneys. And that, the ameliorative effects in vivo of TFA+EM were both superior to TFA or EM. Network pharmacology study results showed that TFA+EM treated DT by regulating the PANoptosis signaling pathway. In vitro study results showed that TFA+EM could improve ROS-induced cell injury, ZBP1-mediatted PANoptosis, and mitochondrial homeostasis in renal tubular epithelial cells under a state of HG, including the protein expression levels of marked molecules of mitochondrial fission, mitochondrial ultrastructure, and membrane potential level. And that, the ameliorative effects in vitro of TFA+EM were both superior to TFA or EM. More importantly, using the NRK52E cells with knock-down ZBP1, the authors found that, indeed, ZBP1 was mediated PANoptosis in renal tubular epithelial cells as an upstream factor. In addition, TFA+EM could regulate the protein expression levels of marked signaling molecules of PANoptosis by targeting ZBP1. In summary, this study clarified that TFA+EM, different from TFA or EM, could attenuate DT with multiple targets by ameliorating mitochondrial homeostasis and inhibiting ZBP1-mediated PANoptosis. These findings provide the clear pharmacological evidence for the clinical treatment of DT with a novel strategy of TFA+EM, which is named "coordinated traditional Chinese and western medicine".
Animals ; Rats ; Mitochondria/metabolism* ; Benzhydryl Compounds/administration & dosage* ; Glucosides/administration & dosage* ; Abelmoschus/chemistry* ; Male ; Homeostasis/drug effects* ; Flavones/administration & dosage* ; Rats, Sprague-Dawley ; Diabetic Nephropathies/physiopathology* ; Drugs, Chinese Herbal/administration & dosage* ; DNA-Binding Proteins/genetics* ; Humans ; Apoptosis/drug effects*

Objective To explore the effects of Yin Yang 1(YY1)on the proliferation and migration of bladder cancer cells and investigate the underlying mechanisms,so as to provide reference for the prevention and treatment of this disease.Methods The expression patterns of YY1 in common genitourinary tumors and their associations with the prognosis were analyzed using data from The Cancer Genome Atlas(TCGA)and the Gene Expression Omnibus(GEO).The efficiency of YY1 knockdown and overexpression in bladder cancer cell lines(T24 and UM-UC-3)was confirmed with quantitative reverse transcription PCR(qRT-PCR)and Western blotting.Cell proliferation and migration were assessed using methylthiazolyldiphenyl-tetrazolium bromide(MTT)and Transwell assays.RNA sequencing followed by bioinformatics analyses,including Gene Ontology(GO),Kyoto Encyclopedia of Genes and Genomes(KEGG),and Gene Set Enrichment Analysis(GSEA),was conducted to predict potential mechanisms.The qRT-PCR and rescue experiments were performed to validate whether YY1 exerted its effects via the E2F1 signaling pathway.Results YY1 was significantly overexpressed in bladder cancer compared to other genitourinary tumors and was associated with higher tumor grade and poorer prognosis(P＜0.05).Functional assays demonstrated that YY1 promoted the proliferation and migration of bladder cancer cells.Transcriptome analyses revealed that YY1 might regulate these processes through the E2F signaling pathway.Moreover,overexpression of E2F1 partially reversed the inhibitory effects of YY1 knockdown on bladder cancer cell proliferation and migration.Conclusion YY1 is upregulated in bladder cancer and is closely associated with tumor grade and unfavorable prognosis.It may facilitate tumor cell proliferation and migration by modulating the E 2F1 signaling pathway.

Objective To screen the risk factors for hypoglycemia in adult intensive care unit(ICU)patients,construct a risk prediction model,and validate its predictive effect.Methods A retrospective study was conducted on adult critically ill patients admitted to the general ICU of Hospital of Chengdu University of Traditional Chinese Medicine from December 2023 to September 2024.Patients admitted from December 2023 to June 2024 served as the modeling group,and those from July to September 2024 as the validation group.A total of 928 patients were included,with 650 in the modeling group and 278 in the validation group.After literature review and expert consultation,27 potential risk factors for hypoglycemia in ICU patients were initially screened,and data were collected including general information[gender,age,acute physiology and chronic health evaluation Ⅱ(APACHEⅡ)score,sequential organ failure assessment(SOFA)score,nutrition risk in critically ill(NUTRIC)score,mechanical ventilation status,hemodialysis status,enteral nutrition status],disease data(sepsis,liver disease history,kidney disease history,diabetes history,hypoglycemia history),blood glucose-related indicators[mean blood glucose,blood glucose coefficient of variation,insulin dosage,intravenous insulin titration use,inotropic drug use,insulin secretagogues(Sulfonylureas and Glinides),and combined use of hypoglycemic drugs(two or more)],and laboratory indicators[serum creatinine(SCr),blood urea nitrogen(BUN),serum albumin(Alb),alanine aminotransferase(ALT),aspartate aminotransferase(AST),total bilirubin(TBil),glomerular filtration rate(GFR)].The patients were divided into a hypoglycemia group and a non-hypoglycemia group based on the occurrence of hypoglycemia.Univariate analysis and binary Logistic regression analysis were used to identify influencing factors of hypoglycemia in adult ICU patients,and a nomogram prediction model was constructed.The area under the receiver operator characteristic curve(AUC)and calibration curves were employed to evaluate the discrimination and calibration of the model.Results The modeling cohort included 552 non-hypoglycemic patients and 98 hypoglycemic patients,with an ICU hypoglycemia incidence rate of 15.1％.Compared with the hypoglycemia group,the non-hypoglycemia group showed significantly lower proportions of patients with renal disease history,diabetes history,hypoglycemia history,undergoing hemodialysis,using intravenous insulin titration,and combined use of hypoglycemic drugs,as well as lower blood glucose coefficient of variation,lower APACHEⅡ scores,and significantly elevated GFR(all P<0.05).Binary Logistic regression analysis was performed using the 9 variables with statistically significant differences in univariate analysis as independent variables and hypoglycemia occurrence as the dependent variable.The results indicated that a history of diabetes,a history of hypoglycemia,APACHEⅡ score,GFR,blood glucose coefficient of variation,and combined use of hypoglycemic drugs were independent risk factors for hypoglycemia in ICU patients[odds ratios(OR)were 1.761,2.095,1.048,0.990,1.029,and 1.975,respectively,and 95％confidence intervals(95％CI)were 1.052-2.949,1.220-3.600,1.022-1.074,0.982-0.997,1.013-1.046,and 1.145-3.408,respectively.The corresponding Pvalues were 0.031,0.007,0.000,0.009,<0.001,0.014].A nomogram prediction model for hypoglycemia in ICU patients was constructed using six independent predictors selected through binary logistic regression analysis.The ROC curve AUC for the modeling group was 0.884(95％CI 0.826-0.941,P=0.250),with a maximum Youden index of 0.713,sensitivity of 92.1％,and specificity of 79.2％.The validation cohort included 38 patients with hypoglycemia and 240 patients without hypoglycemia.Compared with the hypoglycemia group,the non-hypoglycemia group showed significantly lower proportions of patients with a history of diabetes,a history of hypoglycemia,and combined use of hypoglycemic drugs,as well as lower APACHEⅡ scores and lower blood glucose coefficient of variation,with significantly increased GFR(all P<0.05).The ROC curve AUC for the validation cohort was 0.803(95％CI was 0.757-0.849,P=0.138),indicating high discriminatory ability.The predicted probability at the diagnostic cutoff point was P=0.138.The model's diagnostic threshold for predicted probability was P=0.138,while the optimal cut-off value based on the Youden index was 0.513,yielding a sensitivity of 76.5％and specificity of 74.8％,indicating predictive value for hypoglycemia in adult ICU patients.The mean absolute error(MAE)results for the modeling group and validation group were<0.05.The calibration curves of both the modeling and validation groups showed close alignment with the ideal curve,indicating excellent calibration performance of the model.Conclusion The constructed hypoglycemia risk prediction model for adult ICU patients has good predictive performance,which can quickly identify high-risk populations of hypoglycemia in ICU and provide reference for clinical preventive nursing.

Objective To compare the effects of different doses of adenine(ADE)by oral gavage in a mouse model of renal fibrosis(RF),and to provide a more suitable mouse model for further RF research.Methods Thirty C57BL/6J Nifdc mice were divided randomly into a control group,low-dose ADE group(ADE-L group,50 mg/kg),and high-dose ADE group(ADE-H group,100 mg/kg),and the general condition,mortality,and body mass changes of the mice were observed.Serum creatinine(CREA),blood urea nitrogen(BUN),and uric acid(UA)were measured on day 30 to evaluate renal function.Histopathological changes in kidney tissues were observed by hematoxylin-eosin(HE)and Masson staining,and expression levels of fibronectin(FN),collagen Ⅰ(COL Ⅰ),and alpha smooth muscle actin(α-SMA)in kidney tissues were detected by Western Blot.Results The cumulative mortality rates in the ADE-L and ADE-H groups were 91.7％and 58.3％,respectively.The body mass of mice in the ADE-L group was similar to that in the control group(P＞0.05),but the body mass of mice in the ADE-H group was significantly lower than that of mice in the control and ADE-L groups from day 3 to day 30(P＜0.001).Day 30 CREA and BUN levels in the ADE-L group were similar to those in the blank group,but CREA and BUN levels were significantly increased in the ADE-H group(P＜0.001).There were no significant differences in UA levels among all groups.Inflammatory infiltration and tubular dilatation were observed in the ADE-L group on day 30,accompanied by tubular epithelial necrosis,while crystal accumulation in the tubular lumen and interstitium was observed in the ADE-H group,and the degree of interstitial fibrosis was significantly higher than in the control group(P＜0.01).Expression levels of interstitial fibrosis-related proteins in the ADE-H group on day 30 were significantly higher than in the control and ADE-L groups(P＜0.05,P＜0.01 or P＜0.001).Conclusions Both 50 and 100 mg/kg of ADE can be used to establish a mouse model of RF,with different doses leading to varying degrees of renal injury.Mice in the ADE-L group developed mild interstitial fibrosis on day 30,while mice in the ADE-H group developed moderate to severe interstitial fibrosis.

Objective To compare the effects of different doses of adenine(ADE)by oral gavage in a mouse model of renal fibrosis(RF),and to provide a more suitable mouse model for further RF research.Methods Thirty C57BL/6J Nifdc mice were divided randomly into a control group,low-dose ADE group(ADE-L group,50 mg/kg),and high-dose ADE group(ADE-H group,100 mg/kg),and the general condition,mortality,and body mass changes of the mice were observed.Serum creatinine(CREA),blood urea nitrogen(BUN),and uric acid(UA)were measured on day 30 to evaluate renal function.Histopathological changes in kidney tissues were observed by hematoxylin-eosin(HE)and Masson staining,and expression levels of fibronectin(FN),collagen Ⅰ(COL Ⅰ),and alpha smooth muscle actin(α-SMA)in kidney tissues were detected by Western Blot.Results The cumulative mortality rates in the ADE-L and ADE-H groups were 91.7％and 58.3％,respectively.The body mass of mice in the ADE-L group was similar to that in the control group(P＞0.05),but the body mass of mice in the ADE-H group was significantly lower than that of mice in the control and ADE-L groups from day 3 to day 30(P＜0.001).Day 30 CREA and BUN levels in the ADE-L group were similar to those in the blank group,but CREA and BUN levels were significantly increased in the ADE-H group(P＜0.001).There were no significant differences in UA levels among all groups.Inflammatory infiltration and tubular dilatation were observed in the ADE-L group on day 30,accompanied by tubular epithelial necrosis,while crystal accumulation in the tubular lumen and interstitium was observed in the ADE-H group,and the degree of interstitial fibrosis was significantly higher than in the control group(P＜0.01).Expression levels of interstitial fibrosis-related proteins in the ADE-H group on day 30 were significantly higher than in the control and ADE-L groups(P＜0.05,P＜0.01 or P＜0.001).Conclusions Both 50 and 100 mg/kg of ADE can be used to establish a mouse model of RF,with different doses leading to varying degrees of renal injury.Mice in the ADE-L group developed mild interstitial fibrosis on day 30,while mice in the ADE-H group developed moderate to severe interstitial fibrosis.

Objective To explore the effects of Yin Yang 1(YY1)on the proliferation and migration of bladder cancer cells and investigate the underlying mechanisms,so as to provide reference for the prevention and treatment of this disease.Methods The expression patterns of YY1 in common genitourinary tumors and their associations with the prognosis were analyzed using data from The Cancer Genome Atlas(TCGA)and the Gene Expression Omnibus(GEO).The efficiency of YY1 knockdown and overexpression in bladder cancer cell lines(T24 and UM-UC-3)was confirmed with quantitative reverse transcription PCR(qRT-PCR)and Western blotting.Cell proliferation and migration were assessed using methylthiazolyldiphenyl-tetrazolium bromide(MTT)and Transwell assays.RNA sequencing followed by bioinformatics analyses,including Gene Ontology(GO),Kyoto Encyclopedia of Genes and Genomes(KEGG),and Gene Set Enrichment Analysis(GSEA),was conducted to predict potential mechanisms.The qRT-PCR and rescue experiments were performed to validate whether YY1 exerted its effects via the E2F1 signaling pathway.Results YY1 was significantly overexpressed in bladder cancer compared to other genitourinary tumors and was associated with higher tumor grade and poorer prognosis(P＜0.05).Functional assays demonstrated that YY1 promoted the proliferation and migration of bladder cancer cells.Transcriptome analyses revealed that YY1 might regulate these processes through the E2F signaling pathway.Moreover,overexpression of E2F1 partially reversed the inhibitory effects of YY1 knockdown on bladder cancer cell proliferation and migration.Conclusion YY1 is upregulated in bladder cancer and is closely associated with tumor grade and unfavorable prognosis.It may facilitate tumor cell proliferation and migration by modulating the E 2F1 signaling pathway.

Objective To screen the risk factors for hypoglycemia in adult intensive care unit(ICU)patients,construct a risk prediction model,and validate its predictive effect.Methods A retrospective study was conducted on adult critically ill patients admitted to the general ICU of Hospital of Chengdu University of Traditional Chinese Medicine from December 2023 to September 2024.Patients admitted from December 2023 to June 2024 served as the modeling group,and those from July to September 2024 as the validation group.A total of 928 patients were included,with 650 in the modeling group and 278 in the validation group.After literature review and expert consultation,27 potential risk factors for hypoglycemia in ICU patients were initially screened,and data were collected including general information[gender,age,acute physiology and chronic health evaluation Ⅱ(APACHEⅡ)score,sequential organ failure assessment(SOFA)score,nutrition risk in critically ill(NUTRIC)score,mechanical ventilation status,hemodialysis status,enteral nutrition status],disease data(sepsis,liver disease history,kidney disease history,diabetes history,hypoglycemia history),blood glucose-related indicators[mean blood glucose,blood glucose coefficient of variation,insulin dosage,intravenous insulin titration use,inotropic drug use,insulin secretagogues(Sulfonylureas and Glinides),and combined use of hypoglycemic drugs(two or more)],and laboratory indicators[serum creatinine(SCr),blood urea nitrogen(BUN),serum albumin(Alb),alanine aminotransferase(ALT),aspartate aminotransferase(AST),total bilirubin(TBil),glomerular filtration rate(GFR)].The patients were divided into a hypoglycemia group and a non-hypoglycemia group based on the occurrence of hypoglycemia.Univariate analysis and binary Logistic regression analysis were used to identify influencing factors of hypoglycemia in adult ICU patients,and a nomogram prediction model was constructed.The area under the receiver operator characteristic curve(AUC)and calibration curves were employed to evaluate the discrimination and calibration of the model.Results The modeling cohort included 552 non-hypoglycemic patients and 98 hypoglycemic patients,with an ICU hypoglycemia incidence rate of 15.1％.Compared with the hypoglycemia group,the non-hypoglycemia group showed significantly lower proportions of patients with renal disease history,diabetes history,hypoglycemia history,undergoing hemodialysis,using intravenous insulin titration,and combined use of hypoglycemic drugs,as well as lower blood glucose coefficient of variation,lower APACHEⅡ scores,and significantly elevated GFR(all P<0.05).Binary Logistic regression analysis was performed using the 9 variables with statistically significant differences in univariate analysis as independent variables and hypoglycemia occurrence as the dependent variable.The results indicated that a history of diabetes,a history of hypoglycemia,APACHEⅡ score,GFR,blood glucose coefficient of variation,and combined use of hypoglycemic drugs were independent risk factors for hypoglycemia in ICU patients[odds ratios(OR)were 1.761,2.095,1.048,0.990,1.029,and 1.975,respectively,and 95％confidence intervals(95％CI)were 1.052-2.949,1.220-3.600,1.022-1.074,0.982-0.997,1.013-1.046,and 1.145-3.408,respectively.The corresponding Pvalues were 0.031,0.007,0.000,0.009,<0.001,0.014].A nomogram prediction model for hypoglycemia in ICU patients was constructed using six independent predictors selected through binary logistic regression analysis.The ROC curve AUC for the modeling group was 0.884(95％CI 0.826-0.941,P=0.250),with a maximum Youden index of 0.713,sensitivity of 92.1％,and specificity of 79.2％.The validation cohort included 38 patients with hypoglycemia and 240 patients without hypoglycemia.Compared with the hypoglycemia group,the non-hypoglycemia group showed significantly lower proportions of patients with a history of diabetes,a history of hypoglycemia,and combined use of hypoglycemic drugs,as well as lower APACHEⅡ scores and lower blood glucose coefficient of variation,with significantly increased GFR(all P<0.05).The ROC curve AUC for the validation cohort was 0.803(95％CI was 0.757-0.849,P=0.138),indicating high discriminatory ability.The predicted probability at the diagnostic cutoff point was P=0.138.The model's diagnostic threshold for predicted probability was P=0.138,while the optimal cut-off value based on the Youden index was 0.513,yielding a sensitivity of 76.5％and specificity of 74.8％,indicating predictive value for hypoglycemia in adult ICU patients.The mean absolute error(MAE)results for the modeling group and validation group were<0.05.The calibration curves of both the modeling and validation groups showed close alignment with the ideal curve,indicating excellent calibration performance of the model.Conclusion The constructed hypoglycemia risk prediction model for adult ICU patients has good predictive performance,which can quickly identify high-risk populations of hypoglycemia in ICU and provide reference for clinical preventive nursing.

Objective To investigate the expression and clinical significance of serum long non-coding RNA small nucleolar RNA host gene 16(lncRNA SNHG16)and mothers against decapentaplegic homolog 4(SMAD4)in elderly patients with chronic obstructive pulmonary disease(COPD)and pulmonary infection(PI).Methods A total of 237 elderly COPD patients admitted to the hospital from January 2021 to January 2023 were enrolled in the study.Among them,117 patients with concomitant PI were classified as the concur-rent group,and 120 patients without concomitant PI were classified as the COPD group.Real-time fluores-cence quantitative polymerase chain reaction(qRT-PCR)was applied to detect the expression level of serum lncRNA SNHG16 in two groups.Enzyme linked immunosorbent assay(ELISA)was applied to detect the lev-el of SMAD4 in patients'serum.Simplified clinical pulmonary infection scale(sCPIS)was used to evaluate the degree of PI of patients in the concurrent group.Multivariate Logistic regression was applied to analyze the in-fluencing factors of PI in elderly COPD patients.Correlation between serum lncRNA SNHG16,SMAD4 levels and sCPIS in elderly COPD patients with PI was analyzed by using Spearman correlation analysis.Receiver op-erating characteristic(ROC)curve was applied to analyze the diagnostic value of serum lncRNA SNHG16 and SMAD4 levels in elderly COPD patients with PI.Results The serum relative expression level of lncRNA SNHG16 in the concurrent group was higher than that in the COPD group,but the serum SMAD4 level was lower than that in the COPD group(P<0.05).In addition,the proportions of patients with age≥70 years,smoking history,complicated with diabetes and COPD course≥5 years and the levels of tumor necrosis fac-tor-α(TNF-α),interferon-γ(INF-γ)in the concurrent group were higher than those in the COPD group,and FEV1/FVC and the level of interleukin-10(IL-10)in concurrent group were lower than those in COPD group(P<0.05).Multivariate Logistic analysis showed that age≥70 years old,complicated with diabetes,COPD course≥5 years,high levels of TNF-α,INF-γ and lncRNA SNHG16 were risk factors for elderly patients with COPD complicated with PI(P<0.05),but high FEV1/FVC and high levels of SMAD4 and IL-10 were protective factors(P<0.05).Spearman correlation analysis showed that serum relative expression level of ln-cRNA SNHG16 was positively correlated with sCPIS in COPD patients with PI(r=0.505,P<0.001),while SMAD4 level was negatively correlated with sCPIS(r=-0.550,P<0.001).The area under the curve(AUC)of the combined diagnosis of serum lncRNA SNHG16 and SMAD4 for PI in elderly COPD patients was higher than those of individual diagnosis(Z=2.416,P=0.016;Z=2.375,P=0.018).Conclusion The serum relative expression level of lncRNA SNHG16 increases and SMAD4 level decreases in elderly COPD pa-tients with PI,both are influencing factors for elderly COPD patients complicated with PI,and both are related to the degree of PI in patients,and both have diagnostic value for elderly COPD patients complicated with PI,and the diagnostic efficacy of combined detection is better.