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Abstract Background Ischemia reperfusion (IR) causes impaired myocardial function, and autophagy activation ameliorates myocardial IR injury. Isoliquiritigenin (ISO) has been found to protect myocardial tissues via AMPK, with exerting anti-tumor property through autophagy activation. This study aims to investigate ISO capacity to attenuate myocardial IR through autophagy activation mediated by AMPK/mTOR/ULK1 signaling. Methods ISO effects were explored by SD rats and H9c2 cells. IR rats and IR-induced H9c2 cell models were established by ligating left anterior descending (LAD) coronary artery and hypoxia/re-oxygenation, respectively, followed by low, medium and high dosages of ISO intervention (Rats: 10, 20, and 40 mg/kg; H9c2 cells: 1, 10, and 100 μmol/L). Myocardial tissue injury in rats was assessed by myocardial function-related index, HE staining, Masson trichrome staining, TTC staining, and ELISA. Autophagy of H9c2 cells was detected by transmission electron microscopy (TEM) and immunofluorescence. Autophagy-related and AMPK/mTOR/ULK1 pathway-related protein expressions were detected with western blot. Results ISO treatment caused myocardial function improvement, and inhibition of myocardial inflammatory infiltration, fibrosis, infarct area, oxidative stress, CK-MB, cTnI, and cTnT expression in IR rats. In IR-modeled H9c2 cells, ISO treatment lowered apoptosis rate and activated autophagy and LC3 fluorescence expression. In vivo and in vitro, ISO intervention exhibited enhanced Beclin1, LC3II/LC3I, and p-AMPK/AMPK levels, whereas inhibited P62, p-mTOR/mTOR and p-ULK1(S757)/ULK1 protein expression, activating autophagy and protecting myocardial tissues from IR injury. Conclusion ISO treatment may induce autophagy by regulating AMPK/mTOR/ULK1 signaling, thereby improving myocardial IR injury, as a potential candidate for treatment of myocardial IR injury.

Abstract Background Acute lung injury (ALI) is strongly associated with hospitalization and mortality in patients with sepsis. Recent evidence suggests that pyroptosis mediated by NLRP3(NOD-, LRR- and pyrin domain-containing 3) inflammasome activation plays a key role in sepsis. However, the mechanism of NLRP3 inflammasome activation in sepsis-induced lung injury remains unclear. Results in this study, we demonstrated that NLRP3 inflammasome was activated by the down-regulation of heat shock protein family A member 8 (HSPA8) in Lipopolysaccharide (LPS) and adenosine triphosphate (ATP)-treated mouse alveolar epithelial cells (AECs). Geranylgeranylacetone (GGA)-induced HSPA8 overexpression in cecum ligation and puncture (CLP) mice could significantly reduce systemic inflammatory response and mortality, effectively protect lung function, whilst HSPA8 inhibitor VER155008 aggravated this effect. The inhibition of HSPA8 was involved in sepsis induced acute lung injury by promoting pyroptosis of AECs. The down-regulation of HSPA8 activated NLRP3 inflammasome to mediate pyroptosis by promoting the degradation of E3 ubiquitin ligase S-phase kinase-associated protein 2 (SKP2). In addition, when stimulated by LPS and ATP, down-regulated SKP2 promoted pyroptosis of AECs by further attenuating ubiquitination of NLRP3. Adeno-associated virus 9-SKP2(AAV9-SKP2) could promote NLRP3 ubiquitination and degradation, alleviate lung injury and inhibit systemic inflammatory response in vivo. Conclusion in summary, our study shows there is strong statistical evidence that the suppression of HSPA8 mediates alveolar epithelial pyroptosis by promoting the degradation of E3 ubiquitin ligase SKP2 and subsequently attenuating the ubiquitination of NLRP3 to activate the NLRP3 inflammasome, which provides a new perspective and therapeutic target for the treatment of sepsis-induced lung injury.

BackgroundAtrial fibrillation (AF) is a prevalent cardiac arrhythmia associated with substantial morbidity and mortality. Oxidative stress (OS) has been implicated in the pathogenesis of AF, suggesting that targeting OS-related genes could offer novel therapeutic opportunities. This study aimed to identify causal OS-related genes contributing to AF through a comprehensive multi-omics Summary-based Mendelian Randomization (SMR) approach.MethodsThis study integrated data from genome-wide association studies (GWAS) with methylation quantitative trait loci (mQTL), expression QTL (eQTL), and protein QTL (pQTL) to explore the relationships between oxidative stress-related (OS-related) genes and AF risk. Genes associated with oxidative stress and AF were obtained from the Nielsen et al. study (discovery) and the FinnGen study (replication). The SMR analysis and HEIDI test were utilized to assess causal associations, followed by Bayesian co-localization analysis (PPH4 > 0.5) to confirm shared causal variants. Multi-omics data were employed to analyze the associations within mQTL-eQTL pathways. A two-sample MR analysis was conducted for sensitivity verification. The significance of findings was determined using a false discovery rate (FDR) < 0.05 and p_HEIDI > 0.01.ResultsAt the DNA methylation level, 19 CpG sites near 7 unique genes were found to have causal effects on AF and strong co-localization evidence support (PPH4 > 0.70). At the gene expression level, six oxidative stress-related genes from eQTLGen and three from GTEx (v8), including TNFSF10, CDKN1A, ALOX15, TTN, PTK2, ALB, KCNJ5, and CASQ2, were found to have causal effects on AF in the sensitivity and co-localization analyses (PPH4 > 0.50). At the circulating protein level, both ALAD (OR 0.898, 95% CI 0.845–0.954, PPH4 = 0.67) and APOH (OR 0.896, 95% CI 0.844–0.952, PPH4 = 0.93) were associated with a lower risk of AF, and APOH was validated in the replication group. After integrating the multi-omics data between mQTL and eQTL, we identified two oxidative stress-related genes, TTN and CASQ2. The methylation of cg09915519 and cg10087519 in TTN was associated with higher expression of TTN and a lower risk of AF, which aligns with the negative effect of TTN gene expression on AF risk. TTN may play a protective role in AF.ConclusionThis study identified several OS-related genes, particularly TTN, as having causal roles in AF, which were verified across three-omics pathways. The findings underscore the importance of these genes in AF pathogenesis and highlight their potential as therapeutic targets. The integration of multi-omics data provides a comprehensive understanding of the molecular mechanisms underlying AF, paving the way for targeted therapeutic strategies.

Abstract Background Diabetic angiogenesis is closely associated with disabilities and death caused by diabetic microvascular complications. Advanced glycation end products (AGEs) are abnormally accumulated in diabetic patients and are a key pathogenic factor for diabetic angiogenesis. The present study focuses on understanding the mechanisms underlying diabetic angiogenesis and identifying therapeutic targets based on these mechanisms. Methods In this study, AGE-induced angiogenesis serves as a model to investigate the mechanisms underlying diabetic angiogensis. Mouse aortic rings, matrigel plugs, and HUVECs or 293T cells were employed as research objects to explore this pathological process by using transcriptomics, gene promoter reporter assays, virtual screening and so on. Results Here, we found that AGEs activated Wnt/β-catenin signaling pathway and enhanced the β-catenin protein level by affecting the expression of β-catenin degradation-related genes, such as FZDs (Frizzled receptors), LRPs (LDL Receptor Related Proteins), and AXIN1. AGEs could also mediate β-catenin Y142 phosphorylation through VEGFR1 isoform5. These dual effects of AGEs elevated the nuclear translocation of β-catenin and sequentially induced the expression of KDR (Kinase Insert Domain Receptor) and HDAC9 (Histone Deacetylase 9) by POU5F1 and NANOG, respectively, thus mediating angiogenesis. Finally, through virtual screening, Bioymifi, an inhibitor that blocks VEGFR1 isoform5-β-catenin complex interaction and alleviates AGE-induced angiogenesis, was identified. Conclusion Collectively, this study offers insight into the pathophysiological functions of β-catenin in diabetic angiogenesis.

Objective: To identify factors related to poor prognosis in patients with cerebral infarction (CI) and to construct and validate a personalized prediction model based on these factors. Methods: A retrospective analysis was conducted on the clinical and follow-up data of 857 patients with CI who were diagnosed in the neurology department of a tertiary A hospital in Anhui Province, China from April 2020 to March 2022. Based on follow-up data and the Modified Rankin Scale (mRS) score one year after discharge, patients were divided into a good prognosis group (793 cases, mRS ≤2) and a poor prognosis group (64 cases, mRS >2). Multivariate logistic regression analysis was used to identify independent risk factors, which were then used to establish a nomogram model. The predictive performance of the model was evaluated using the area under the receiver operating characteristic curve (ROC, AUC), and the calibration curve was used to evaluate the calibration of the nomogram. Results: There was a statistically significant difference in the distribution of eight variables between the groups, including post-discharge use of biguanide hypoglycemic drugs, insulin, systolic blood pressure, exercise status, alcohol consumption, smoking status, age, and gender (P

Galectin-1 (Gal-1), a member of a highly conserved family of animal lectins, plays a crucial role in controlling inflammation and neovascularization. However, the potential role of Gal-1 in preventing myocarditis remains uncertain. We aimed to explore the functions and mechanisms of Gal-1 in preventing myocarditis. In vivo, C57/BL6 mice were pre-treated with or without Gal-1 and then exposed to lipopolysaccharide (LPS) to induce myocarditis. Subsequently, cardiac function, histopathology, inflammation, oxidative stress, and apoptosis of myocardial tissues were detected. Following this, qRT-PCR and Western blotting were applied to measure iNOS, COX2, TXNIP, NLRP3 and Caspase-1 p10 expressions. In vitro, H9c2 cells pre-treated with different doses of Gal-1 were stimulated by LPS to induce myocarditis models. CCK8, flow cytometry and reactive oxygen species (ROS) assay were then employed to estimate cell viability, apoptosis and oxidative stress. Furthermore, Nrf2 and HO-1 protein expressions were evaluated by Western blotting in vivo and in vitro. The results showed that in vivo, Gal-1 pre-treatment not only moderately improved cardiac function and cardiomyocyte apoptosis, but also ameliorated myocardial inflammation and oxidative damage in mice with myocarditis. Furthermore, Gal-1 inhibited TXNIP-NLRP3 inflammasome activation. In vitro, Gal-1 pre-treatment prevented LPS-induced apoptosis, cell viability decrease and ROS generation. Notably, Gal-1 elevated HO-1, total Nrf2 and nuclear Nrf2 protein expressions both in vivo and in vitro. In conclusion, pre-treatment with Gal-1 exhibited cardioprotective effects in myocarditis via anti-inflammatory and antioxidant functions, and the mechanism may relate to the Nrf2 pathway, which offered new solid evidence for the use of Gal-1 in preventing myocarditis.

Advanced glycation endproducts (AGEs) have been confirmed to play a causative role in the development of diabetic nephropathy (DN). In this study, we revealed that AGE-induced kidney injury with characteristic patterns in different stages and moesin phosphorylation plays a role in these processes. In WT mice treated with AGE-modified bovine serum albumin (AGE-BSA), distinct abnormal angiogenesis in Bowman’s capsule of the kidney emerged early after 1 m under AGE-BSA stimulation, while these neovessels became rare after 6 m. AGE-BSA also induced glomerular hypertrophy and mesangial expansion at 1 m but glomerular atrophy and fibrosis at 6 m. Electron microscopy imaging demonstrated the damage of foot process integrity in podocytes and the uneven thickening of the glomerular basement membrane in the AGE-BSA-treated group, which was more significant after 6 m of AGE-BSA treatment than 1 m. The kidney dysfunction appeared along with these AGE-induced morphological changes. However, these AGE-BSA-induced pathological changes were significantly attenuated in RAGE-knockout mice. Moreover, moesin phosphorylation was accompanied by AGE-BSA-induced alterations and moesin deficiency in mice attenuated by AGE-BSA-induced fibrosis. The investigation on glomerular endothelial cells (GECs) also confirmed that the phosphorylation of moesin T558 is critical in AGE-induced tube formation. Overall, this study suggests that AGEs mediate kidney injury with characteristic patterns by binding with RAGE and inducing moesin phosphorylation.

Aberrant pro-inflammatory activation of Kupffer cells (KCs) is strongly involved in the pathogenesis of septic liver injury. Recent evidence indicates the crucial roles of excessive stimulator of interferon genes (STING) signaling activation during sepsis. However, the role of STING signaling in septic liver injury remains unclear. In this study, we demonstrated that STING signaling was markedly activated in KCs isolated from wild type mice after lipopolysaccharide (LPS) treatment. STING deficiency effectively protected liver function, attenuated systemic inflammatory response and decreased mortality in LPS-treated mice, which were aggravated by STING agonist (DMXAA). Importantly, STING signaling activation in KCs contributed to LPS-induced liver injury through promoting hepatocyte death. Mechanistically, STING signaling could be activated by release of mitochondrial DNA (mtDNA) through dynamin-related protein 1 (DRP1)-dependent mitochondrial fission in LPS-treated KCs. Additionally, LPS stimulation enhanced DRP1-dependent mitochondrial ROS production, which promoted the leak of mtDNA into the cytosol and subsequent STING signaling activation in KCs. The in vivo experiments showed that pharmacological inhibition of DRP1 with Mdivi-1 partially prevented the activation of STING signaling in KCs isolated from LPS-challenged mice, as well as alleviated liver injury and inhibited systemic inflammatory response. In summary, our study comprehensively confirmed that STING signaling senses the DRP1-dependent release of mtDNA in KCs and its activation might play a key role in LPS-induced liver injury, which offers new sights and therapeutic targets for management of septic liver injury.

Abstract Our previous studies showed that silent mating-type information regulation 2 homologue-1 (SIRT1, a deacetylase) upregulation could attenuate sepsis-induced acute kidney injury (SAKI). Upregulated SIRT1 can deacetylate certain autophagy-related proteins (Beclin1, Atg5, Atg7 and LC3) in vitro. However, it remains unclear whether the beneficial effect of SIRT1 is related to autophagy induction and the underlying mechanism of this effect is also unknown. In the present study, caecal ligation and puncture (CLP)-induced mice, and an LPS-challenged HK-2 cell line were established to mimic a SAKI animal model and a SAKI cell model, respectively. Our results demonstrated that SIRT1 activation promoted autophagy and attenuated SAKI. SIRT1 deacetylated only Beclin1 but not the other autophagy-related proteins in SAKI. SIRT1-induced autophagy and its protective effect against SAKI were mediated by the deacetylation of Beclin1 at K430 and K437. Moreover, two SIRT1 activators, resveratrol and polydatin, attenuated SAKI in CLP-induced septic mice. Our study was the first to demonstrate the important role of SIRT1-induced Beclin1 deacetylation in autophagy and its protective effect against SAKI. These findings suggest that pharmacologic induction of autophagy via SIRT1-mediated Beclin1 deacetylation may be a promising therapeutic approach for future SAKI treatment.

ObjectiveTo study the role of the receptor for advanced glycation end products (RAGE) in endothelial barrier dysfunction induced by heat stress, to further explore the signal pathway by which RAGE contributes to heat-induced endothelia response, and thereby find a novel target for the clinical treatment of ALI (acute lung injury) induced by heatstroke.MethodsThis study established the animal model of heatstroke using RAGE knockout mice. We observed the role of RAGE in acute lung injury induced by heatstroke in mice by evaluating the leukocytes, neutrophils, and protein concentration in BALF (Bronchoalveolar lavage fluids), lung wet/dry ratio, histopathological changes, and the morphological ultrastructure of lung tissue and arterial blood gas analysis. To further study the mechanism, we established a heat stress model of HUVEC and concentrated on the role of RAGE and its signal pathway in the endothelial barrier dysfunction induced by heat stress, measuring Transendothelial electrical resistance (TEER) and western blot.ResultsRAGE played a key role in acute lung injury induced by heatstroke in mice. The mechanism C-Jun is located in the promoter region of the RAGE gene. C-Jun increased the RAGE protein expression while HSF1 suppressed RAGE protein expression. The overexpressed RAGE protein then increased HUVEC monolayer permeability by activating ERK and P38 MAPK under heat stress.ConclusionThis study indicates the critical role of RAGE in heat stress-induced endothelial hyperpermeability in acute lung injury and suggests that RAGE could be a potential therapeutic target in protecting patients against acute lung injury induced by heatstroke.

Background/Aims: The roots of Averrhoa carambola L. (Oxalidaceae) have long been used as a traditional Chinese medicine for the treatment of headaches, vomiting, coughing and hangovers. 2-dodecyl-6-methoxycyclohexa-2, 5-1, 4-dione (DMDD) has been isolated from A. carambola L. roots, and this study was carried out to investigate the potential beneficial effects of DMDD on neuron apoptosis and memory deficits in Alzheimer's disease. Methods: The effects of a DMDD on learning and memory in APP/PS1 transgenic AD mice in vivo were investigated via Morris water maze and Y-type electric maze tests. In vitro, Cell viability was assessed by CCK-8. Apoptosis was assessed by Annexin V-FITC/PI flow cytometry assay, and transmission electron microscopy assay. Relative quantitative real-time PCR and Western blot were used to determine the expressions of genes and proteins. Results: The spatial learning and memory deficit, fear memory deficit, as well as apoptosis and loss of neuron in hippocampal area of APP/PS1 mice were reversed by DMDD in APP/PS1 transgenic AD mice. DMDD protected against the Aβ1-42-induced apoptosis, loss of mitochondria membrane potential, induction of pro-apoptotic Bcl-2 family protein Bax, reduction of anti-apoptotic Bcl-2 family proteins Bcl-2, and activation of Caspase-3, and -9 in PC-12 cells. The Bcl-2/Bax ratio was also increased in DMDD-pretreated PC-12 cells in vitro and APP/PS1 mice in vivo. Conclusion: DMDD has potential benefit on treating learning and memory deficit in APP/PS1 transgenic AD mice, and its effects may be associated with reversing the apoptosis of neuron via inhibiting Bax/Bcl-2 mediated mitochondrial membrane potential loss.

Targeting tumor microenvironment (TME) is crucial in order to overcome the anti-cancer therapy resistance. In this study, we report the antitumor activity of a newly synthesized β-carboline derivative “B-9-3.” Here, this small molecule showed a promising antitumor activity in vivo along with an enhanced immune response as reflected by a reduction of regulatory T cells and increased CD4+/CD8+ T cells. Further, B-9-3 decreased the number of myofibroblasts not only in the tumor but also in the lung suggesting an anti-metastatic action. The reduction of myofibroblasts was associated with lower expression of epithelial-to-mesenchymal transition markers and a decrease of phosphorylated SMAD2/3 complex indicating the implication of TGF-β signaling pathway in B-9-3’s effect. The blockade of myofibroblasts induction by B-9-3 was also verified in vitro in human fibroblasts treated with TGF-β. To elucidate the mechanism of B-9-3’s action on TGF-β pathway, first, we investigated the molecular interaction between B-9-3 and TGF-β receptors using docking method. Data showed a weak interaction of B-9-3 with the ATP-binding pocket of TGFβRI but a strong one with a ternary complex formed of extracellular domains of TGFβRI, TGFβRII, and TGF-β. In addition, the role of TGFβRI and TGFβRII in B-9-3’s activity was explored in vitro. B-9-3 did not decrease any of the two receptors’ protein level and only reduced phosphorylated SMAD2/3 suggesting that its effect was more probably due to its interaction with the ternary complex rather than decreasing the expression of TGF-β receptors or interfering with their ATP-binding domains. B-9-3 is a small active molecule which acts on the TGF-β signaling pathway and improves the TME to inhibit the proliferation and the metastasis of the tumor with the potential for clinical application.

Advanced glycation end products (AGEs), produced by the non-enzymatic glycation of proteins and lipids under hyperglycemia or oxidative stress conditions, has been implicated to be pivotal in the development of diabetic vascular complications, including diabetic retinopathy. We previously demonstrated that Src kinase played a causative role in AGE-induced hyper-permeability and barrier dysfunction in human umbilical vein endothelial cells (HUVECs). While the increase of vascular permeability is the early event of angiogenesis, the effect of Src in AGE-induced angiogenesis and the mechanism has not been completely revealed. Here, we investigated the impact of Src on AGE-induced HUVECs proliferation, migration, and tubulogenesis. Inhibition of Src with inhibitor PP2 or siRNA decreased AGE-induced migration and tubulogenesis of HUVECs. The inactivation of Src with pcDNA3/flag-SrcK298M also restrained AGE-induced HUVECs proliferation, migration, and tube formation, while the activation of Src with pcDNA3/flag-SrcY530F enhanced HUVECs angiogenesis alone and exacerbated AGE-induced angiogenesis. AGE-enhanced HUVECs angiogenesis in vitro was accompanied with the phosphorylation of ERK in HUVECs. The inhibition of ERK with its inhibitor PD98059 decreased AGE-induced HUVECs angiogenesis. Furthermore, the inhibition and silencing of Src suppressed the AGE-induced ERK activation. And the silencing of AGEs receptor (RAGE) inhibited the AGE-induced ERK activation and angiogenesis as well. In conclusions, this study demonstrated that Src plays a pivotal role in AGE-promoted HUVECs angiogenesis by phosphorylating ERK, and very likely through RAGE-Src-ERK pathway.

Plumbagin and its Cu (II) complex [Cu (plumbagin)2]·H2O have been synthesized, and their antioxidant activities towards the inhibitory effect on DPPH free radical, reducing power, total antioxidant capacity, and inhibition on lipid peroxidation were investigated. Plumbagin and its Cu (II) complex were found to exhibit scavenging activities on DPPH radical with the inhibitory rate of 41% and 24%, respectively. The reducing power of plumbagin was outstanding at the concentrations of 1.0, 1.5, and 2.0 mg/mL, compared to Cu (II) complex and synthetic antioxidant 2,6-di-ter-butyl-4-methylphenol (BHT); the highest level reached 1.333 for plumbagin and 0.581 for Cu (II) complex. Also, the inhibition on lipid peroxidation of plumbagin was higher than that of Cu (II) complex and BHT, 46.4% for plumbagin and 24.5% for Cu (II) complex. The results give a strong impact for designing anticancer drugs, combined with their potential cytotoxic and antioxidant activities, which can be targeted selectively against cancer cells and increase their therapeutic index and additional advantages over other anticancer drugs.

Complexes of copper (II) with hesperetin, naringenin, and apigenin of general composition [CuL2(H2O)2]⋅nH2O (1–3) have been synthesized and characterized by elemental analysis, UV-Vis, FT-IR, ESI-MS, and TG-DTG thermal analysis. The free ligands and the metal complexes have been tested in vitro against human cancer cell lines hepatocellular carcinoma (HepG-2), gastric carcinomas (SGC-7901), and cervical carcinoma (HeLa). Complexes 1 and 3 were found to exhibit growth inhibition of SGC-7901 and HepG2 cell lines with respect to the free ligands; the inhibitory rate of complex 1 is 43.2% and 43.8%, while complex 3 is 46% and 36%, respectively. The interactions of complex 1 and its ligand Hsp with calf thymus DNA were investigated by UV-Vis, fluorescence, and CD spectra. Both complex 1 and Hsp were found to bind DNA in intercalation modes, and the binding affinity of complex 1 was stronger than that of free ligand.

Introduction Mitral regurgitation (MR) is the most common valvular heart disorder, with a morbidity rate of 2.5%. While echocardiography is commonly used in assessing MR, it has many limitations, especially for large-scale MR screening. Cardiac auscultation with electronic stethoscope and artificial intelligence (AI) can be a fast and economical modality for assessing MR severity. Our objectives are (1) to establish a deep neural network (DNN)-based cardiac auscultation method for assessing the severity of MR; and (2) to quantitatively measure the performance of the developed AI-based MR assessment method by virtual clinical trial.Methods and analysis In a cross-sectional design, phonocardiogram will be recorded at the mitral valve auscultation area of outpatients. The enrolled patients will be checked by echocardiography to confirm the diagnosis of MR or no MR. Echocardiographic parameters will be used as gold standard to assess the severity of MR, classified into four levels: none, mild, moderate and severe. The study consists of two stages. First, an MR-related cardiac sound database will be created on which a DNN-based MR severity classifier will be trained. The automatic MR severity classifier will be integrated with the Smartho-D2 electronic stethoscope. Second, the performance of the developed smart device will be assessed in an independent clinical validation data set. Sensitivity, specificity, precision, accuracy and F1 score of the developed smart MR assessment device will be evaluated. Agreement on the performance of the smart device between cardiologist users and patient users will be inspected. The interpretability of the developed model will also be studied with statistical comparisons of occlusion map-guided variables among the four severity groups.Ethics and dissemination The study protocol was approved by the Medical Ethics Committee of Huzhou Central Hospital, China (registration number: 202302009-01). Informed consent is required from all participants. Dissemination will be through conference presentations and peer-reviewed journals.Trial registration number ChiCTR2300069496.

The precise relationship between service innovation and financial outcomes in this context remains ambiguous. This study examines the extent to which service innovation contributes to financial outcomes, analyzing data from 512 manufacturing companies across China from 1993 to 2017, sourced from the CSMAR database. Utilizing OLS regression and fixed effects model method, we identify a positive nonlinear correlation between service innovation and financial performance, highlighting a “service dilemma” that varies between state-owned and private enterprises, which follows a “saddle-type” pattern. In addition, the impact of service innovation shows considerable variation across different industries. This research provides critical insights into optimizing financial performance through strategic service innovation across various types of enterprises and industries. It underscores the importance of tailored industrial strategies and equitable competition in enhancing service innovation. The study’s extensive sample size and its focus on the heterogeneity among enterprise types and industries mark its key contributions to understand service innovation’s role in financial performance.

Introduction Percutaneous coronary intervention (PCI) guided by coronary angiography-derived fractional flow reserve (FFR) or intravascular ultrasound (IVUS) has shown improved clinical outcomes compared with angiography-only-guided PCI. In patients with intermediate stenoses, FFR resulted in fewer coronary interventions and was non-inferior to IVUS with respect to clinical outcomes. However, whether this finding can be applied to angiography-derived FFR in significant coronary artery disease (CAD) remains unclear.Method and analysis The comparison of angiography-derived FFR-guided and IVUS-guided intervention strategies for clinical outcomes in patients with coronary artery disease (FLAVOUR II) trial is a multicentre, prospective, randomised controlled trial. A total of 1872 patients with angiographically significant CAD (stenoses of at least 50% as estimated visually through angiography) in a major epicardial coronary artery will be randomised 1:1 to receive either angiography-derived FFR-guided or IVUS-guided PCI. Patients will be treated with second-generation drug-eluting stent according to the predefined criteria for revascularisation: angiography-derived FFR≤0.8 and minimal lumen area (MLA)≤3 mm2 or 3 mm270%. The primary endpoint is a composite of all-cause death, myocardial infarction and revascularisation at 12 months after randomisation. We will test the non-inferiority of the angiography-derived FFR-guided strategy compared with the IVUS-guided decision for PCI and the stent optimisation strategy.The FLAVOUR II trial will provide new insights into optimal evaluation and treatment strategies for patients with CAD.Ethics and dissemination FLAVOUR II was approved by the institutional review board at each participating site (The Second Affiliated Hospital of Zhejiang University School of Medicine Approval No: 2020LSYD410) and will be conducted in line with the Declaration of Helsinki. Informed consent would be obtained from each patient before their participation. The study results will be submitted to a scientific journal.Trial registration number NCT04397211.