Identification of key proteins as potential biomarkers associated with post-infarction complications in diabetics.

Background: The ability of transcriptome analysis to identify dysregulated pathways and outcome-related genes following myocardial infarction in diabetic patients remains unknown. The present study was designed to detect possible biomarkers associated with the incidence of post-infarction complications in diabetes to assist thedevelopment of novel treatments for this condition.Methods: Two gene expression datasets, GSE12639 and GSE6880, were downloaded from the Gene Expression Omnibus (GEO) database, and then differentially expressed genes (DEGs) were identified between post-infarction diabetics and healthy samples from the left ventricular wall of rats. These DEGs were then arranged into a protein-protein interaction (PPI) network, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) enrichment analyses were performed to explore the functional roles of these genes.Results: In total, 30 DEGs (14 upregulated and 16 downregulated) were shared between these two datasets, as identified through Venn diagram analyses. GO analyses revealed these DEGs to be significantly enriched in ovarian steroidogenesis, fatty acid elongation, biosynthesis of unsaturated fatty acids, synthesis and degradation of ketone bodies, and butanoate metabolism. The PPI network of the DEGs had 14 genes and 70 edges. We identified two key proteins, 3-hydroxymethylglutaryl-CoA synthase 2 (Hmgcs2) and Δ3, Δ2-Enoyl-CoA Delta Isomerase 1 (ECI1), and the upregulated gene Hmgcs2 with the highest score in the MCC method. We generated a co-expression network for the hub genes and obtained the top ten medications suggested for infarction with diabetes.Conclusion: Taken together, the findings of these bioinformatics analyses identified key hub genes associated with the development of myocardial infarction in diabetics. These hub genes and potential drugs may become novel biomarkers for prognosis and precision treatment in the future.

Down-regulation of S1PR2 is correlated with poor prognosis and immune infiltrates in cervical squamous cell carcinoma and endocervical adenocarcinoma.

Objectives: Cervical squamous cell carcinoma and cervical adenocarcinoma (CESC) are the second leading cause of deaths from malignant tumors in women, while their therapeutic and diagnostic aims are still finited. A growing body of evidence indicated that sphingosine-1-phosphate receptor 2 (S1PR2) plays essential roles in the occurrence and development about several human cancers. Nevertheless, the key mechanism and role mechanism of S1PR2 in CESC are still unclear.Methods: We first used Tissue Expression (GTEx) and Genotypic Cancer Genome Atlas (TCGA) data to perform pan-cancer analysis on the expression and prognosis of S1PR2, and found that S1PR2 may have a potential impact on CESC. To generate a protein-protein interaction (PPI) network using the STRING database. The clusterProfiler package is used for feature-rich analysis. The Tumor IMmune Estimation Resource was used to determine the connection between S1PR2 mRNA expression and immune infiltrates. Results: S1PR2 expression in CESC tissues was down-regulated compared with adjacent normal tissues. Kaplan-Meier analysis indicated that compared with patients with high expression of S1PR2, CESC patients with low S1PR2 expression had a worse prognosis. Reduced S1PR2 expression is associated with patients with high clinical stage, more histological types of squamous cell carcinoma, and poor primary treatment outcomes. The receiver operating characteristic curve of S1PR2 was 0.870. Correlation analysis showed that the mRNA expression of S1PR2 was related to immune infiltrates and tumor purity.Conclusion: Down-regulated S1PR2 expression is related to poor survival and immune infiltration in CESC. S1PR2 is a potential biomarker for poor prognosis and as a potential target for CESC immune therapy.

A 3-Mbp fragment on rat chromosome 1 affects susceptibility both to stroke and kidney injury under salt loading in the stroke-prone spontaneously hypertensive rat: a genetic approach using multiple congenic strains.

We have previously reported that a major quantitative trait locus (QTL) responsible for susceptibility to salt-induced stroke in the stroke-prone spontaneously hypertensive rat (SHRSP) is located in a 3-Mbp region on chromosome 1 covered by SHRSP.SHR-(D1Rat23-D1Rat213)/Izm (termed Pr1.31), a congenic strain with segments from SHRSP/Izm introduced into the stroke-resistant SHR/Izm. Here, we attempted to narrow down the candidate region on chromosome 1 further through analyses of subcongenic strains constructed for the target region. Simultaneously, salt-induced kidney injury was evaluated through the measurement of urinary albumin and the gene expression of renal tubular injury markers (Kim-1 and Clu) to explore a possible mechanism leading to the onset of stroke. All subcongenic strains examined in this study showed lower susceptibility to salt-induced stroke than SHRSP. Interestingly, Pr1.31 had the lowest stroke susceptibility when compared with newly constructed subcongenic strains harboring fragments of the congenic sequence in Pr1.31. Although Kim-1 and Clu expression after 1 week of salt loading in Pr1.31 did not differ significantly from those in SHRSP, the urinary albumin level of Pr1.31 was significantly lower than those of the other subcongenic strains and that of SHRSP. The present results indicated that, although the congenic fragment in Pr1.31 harbored the gene(s) related to salt-induced organ damages, further genetic dissection of the candidate region was difficult due to multiple QTLs suggested in this region. Further analysis using Pr1.31 will unveil genetic and pathophysiological mechanisms underlying salt-induced end organ damages in SHRSP.

Effects of direct oral anticoagulants dabigatran and rivaroxaban on the blood coagulation function in rabbits.

The aim of this study was to explore the effects of dabigatran and rivaroxaban on the activities of various coagulation factors. To achieve that, 60 rabbits were randomly divided into experimental groups that received different doses of dabigatran or rivaroxaban. The effects of dabigatran and rivaroxaban on the activities of FII, FV, FVIII, FX, and activated protein C (APC) were analyzed. In the dabigatran groups, activated partial thromboplastin time and thromboplastin time (TT) were prolonged after drug administration, and the activities of FII, FV, FVIII, and FX were inhibited as the drug concentration increased. Low doses of dabigatran inhibited APC activity. In the rivaroxaban groups, APTT and TT were not significantly prolonged after drug administration. In contrast, the high-dose rivaroxaban group exhibited prolonged PT, and the degree of inhibition of the activities of FII, FV, FVIII, and FX increased as the drug concentration increased. Rivaroxaban had no significant effect on APC activity regardless of dosage. As the drug concentration increased, both NOACs had more significant inhibitory effects on the activities of FII, FV, FVIII, and FX. Low concentrations of dabigatran generated an inhibitory effect on APC activity, while high concentrations of dabigatran had no significant effect. Rivaroxaban had no significant effect on APC activity.

How to Set Up Central Isolation Sites to Prevent Re-outbreaks From Imported Cases of COVID-19: The Experience of Shanghai, China.

As strict measures were taken, the coronavirus disease 2019 (COVID-19) epidemic has been gradually brought under control. As a port city, Shanghai's main problem has shifted from treating local cases to preventing foreign imports. To prevent the re-outbreak of COVID-19 caused by imported cases, the Shanghai government has set up central isolation sites for all people entering the country from abroad to be placed under medical observation. This report describes how to set up central isolation sites and run them effectively. We put isolation sites in transformed hotels, arranged personnel according to a huge data network, and set up specific procedures to manage guests. The epidemic situation in Shanghai has confirmed the feasibility and effectiveness of the methods that other jurisdictions can adapt for their use.

Circulating LIPCAR is a potential biomarker of heart failure in patients post-acute myocardial infarction.

In heart failure (HF) patients with reduced ejection fraction, LIPCAR, a long noncoding RNA is elevated and is associated with left ventricular remodeling and poor prognosis. We studied the role of LIPCAR in patients with HF post-acute myocardial infarction (AMI) to find biomarkers for early detection of HF. We conducted a study of 127 patients with AMI, of which 59 were patients with HF post-AMI. LIPCAR levels were higher in HF patients post-AMI than patients without HF, and LIPCAR had a high predictive value for diagnosis of HF, which was estimated by receiver operating characteristic curves (AUC: 0.985). The results indicate that LIPCAR may be a marker of early HF after AMI.

lncRNA-NRF is a Potential Biomarker of Heart Failure After Acute Myocardial Infarction.

Long non-coding RNAs (lncRNAs) are a new focus in cardiovascular diseases. The necrosis-related factor (NRF) is a newly discovered lncRNA, which is increased in myocardial injury. We investigated the role of lncRNA-NRF in heart failure (HF) after acute myocardial infarction (AMI) to find a biomarker for early HF detection. This was a cross-sectional study of 76 AMI patients with HF and 58 AMI patients without HF. lncRNA-NRF was shown to be increased in AMI patients with HF compared with AMI patients without HF and had predictive value for diagnosis of HF. It had a high diagnostic value for HF (AUC, 0.975), while the AUC for N-terminal pro-brain natriuretic peptide was 0.720. Our findings suggest that lncRNA-NRF may represent a marker of risk for development of HF post-AMI.

Exosomes from adipose-derived mesenchymal stem cells ameliorate cardiac damage after myocardial infarction by activating S1P/SK1/S1PR1 signaling and promoting macrophage M2 polarization.

Exosomes derived from mesenchymal stem cells (MSCs) are known to participate in myocardial repair after myocardial infarction (MI), but the mechanism remains unclear. Here, we isolated exosomes from adipose-derived MSCs (ADSCs) and examined their effect on MI-induced cardiac damage. To examine the underlying mechanism, H9c2 cells, cardiac fibroblasts, and HAPI cells were used to study the effect of ADSC-exosomes on hypoxia-induced H9c2 apoptosis, TGF-ß1-induced fibrosis of cardiac fibroblasts, and hypoxia-induced macrophage M1 polarization using qRT-PCR, western blot, ELISA, immunohistochemistry, immunofluorescence and flow cytometry. ADSC-exosome treatment mitigated MI-induced cardiac damage by suppressing cardiac dysfunction, cardiac apoptosis, cardiac fibrosis, and inflammatory responses in vitro and in vivo. In addition, ADSC-exosome treatment promoted macrophage M2 polarization. Further experiments found that S1P/SK1/S1PR1 signaling was involved in the ADSC-exosome-mediated myocardial repair. Silencing of S1PR1 reversed the inhibitory effect of ADSC-exosomes on MI-induced cardiac apoptosis and fibrosis in vitro. ADSC-exosome-induced macrophage M2 polarization was also reversed after downregulation of S1PR1 under hypoxia conditions, which promoted NFκB and TGF-ß1 expression, and suppressed the MI-induced cardiac fibrosis and inflammatory response. In sum, these results indicate that ADSC-derived exosomes ameliorate cardiac damage after MI by activating S1P/SK1/S1PR1 signaling and promoting macrophage M2 polarization.

Effects of miR­103a­3p on the autophagy and apoptosis of cardiomyocytes by regulating Atg5.

Autophagy and apoptosis are associated with cardiovascular diseases. Emerging evidence shows that microRNAs (miRs) are critical in the development of pathological processes underlying cardiovascular diseases by regulating the induction of apoptosis and autophagy. The present study aimed to investigate the role of miR­103a­3p in cardiomyocyte injury through autophagy and apoptosis. H9c2 cells were cultured under hypoxia and reoxygenation (H/R) conditions and were used to mimic cells under ischemia. The transfection of cells with miR­103a­3p (mimics and inhibitors) was performed to examine its function in cardiomyocytes. The expression levels of miR­103a­3p were evaluated by reverse transcription­quantitative polymerase chain reaction analysis. Cell viability was determined using an MTT assay, and the lactate dehydrogenase assay (LDH) was used to investigate cell injury. The expression levels of B­cell lymphoma 2 (Bcl­2), Bcl­2­associated X protein, Beclin­1, autophagy­related 5 (Atg5), cleaved caspase­3 and cleaved caspase­9 were detected using western blotting. Immunofluorescence assays were performed to detect the expression of LC3 as a marker of autophagy. The target gene of miR­103a­3p was identified using dual­luciferase reporter assays. The results revealed that the expression levels of miR­103a­3p were significantly downregulated in cardiomyocytes under H/R conditions. Injury of the cardiomyocytes was evaluated under H/R conditions. Following transfection of the cells with miR­103a­3p inhibitors, cell injury was increased, as determined by LDH and MTT assays. The expression levels of apoptotic proteins were consistent with the results obtained in the LDH and cell viability assays. The induction of autophagy was increased in cells under H/R conditions and cells with miR­103a­3p inhibitor transfection, whereas the induction of autophagy was decreased in cells transfected with miR­103a­3p mimics. In addition, the data indicated that miR­103a­3p directly targeted Atg5, which regulated the induction of autophagy and apoptosis. Taken together, these findings indicate that, following the inhibition of miR­103a­3p, Atg5 promotes autophagy and apoptosis in cardiomyocytes by directly targeting Atg5. Therefore, miR­103a­3p can be considered a potential therapeutic target for myocardial ischemia.

Retracted: Upregulated microRNA-132 rescues cardiac fibrosis and restores cardiocyte proliferation in dilated cardiomyopathy through the phosphatase and tensin homolog-mediated PI3K/Akt signal transduction pathway.

Cardiac fibrosis is known to be present in dilated cardiomyopathy (DCM) and it predicts the occurrence of sudden death and congestive heart failure. The aim of our study is to investigate the expression of microRNA-132 (miR-132) and its effect on cardiocyte proliferation, apoptosis, and cardiac fibrosis by binding to phosphatase and tensin homolog (PTEN) through the phosphateidylinositol 3-kinase (PI3K)/protein kinase (Akt) signal transduction pathway in DCM rats. DCM rat models induced by doxorubicin were established and confirmed by an ultrasonic cardiogram. Epithelial cells were treated with inhibitors, activators, and small interfering RNAs to identify the mechanisms by which miR-132 controls cardiocyte activity and cardiac fibrosis. Angiotensin II (Ang II) and aldosterone (ALD) expressions were detected by an enzyme-linked immunosorbent assay. The relationship between PTEN and miR-132 was verified by a dual-luciferase reporter assay. Cell proliferation and apoptosis were tested by the MTT assay and flow cytometry. PTEN was determined to be the target gene of miR-132. Rat models of DCM exhibited a lower level of miR-132, PI3K, Akt, B-cell lymphoma 2, collagen I, and collagen III, but a higher level of PTEN, Bcl-2-associated X protein, and proliferating cell nuclear antigen as well as inflammatory response (Ang II and ALD), accompanied by declined cardiocyte proliferation and elevated apoptosis and cardiac fibrosis. Upregulated miR-132 or silenced PTEN activated the PI3K/Akt pathway, thus facilitating cardiocyte proliferation and repressing cardiocyte apoptosis and cardiac fibrosis, as well as inflammatory responses. Downregulated miR-132 reversed this tendency. These findings indicate that miR-132 activates the PI3K/Akt pathway by inhibiting PTEN expression, thus facilitating cardiocyte proliferation and inhibiting apoptosis and cardiac fibrosis in DCM rats.

GDF11 Attenuated ANG II-Induced Hypertrophic Cardiomyopathy and Expression of ANP, BNP and Beta-MHC Through Down- Regulating CCL11 in Mice.

BACKGROUND: Growth differentiation factor 11 (GDF11) decreases with age, and increased C-C motif chemokine 11 (CCL11) is involved in aging. However, the effects of GDF11 on Angiotensin II (ANG II)-induced hypertrophic cardiomyopathy and expression of markers for volume overload and hypertrophy such as ANP, BNP and beta-MHC, as well as the relationship between GDF11 and CCL11 in hypertrophic cardiomyopathy are unclear. Therefore, the current study aimed to examine the effects of GDF11 on ANG II-induced hypertrophic cardiomyopathy and expression of ANP, BNP and beta-MHC in mice, and explore possible molecular mechanisms. METHODS: Vectors were constructed and viruses were packaged. Mouse cardiomyocytes were treated with ANG II for 24 h. Meanwhile, mouse cardiomyocytes were divided into 4 groups: (1) control; (2) ANG II; (3) ANG II+GDF11; and (4) ANG II+CCL11. Furthermore, mouse cardiomyocytes were treated with GDF11 and CCL11 proteins for 48 h, respectively. The thickness of IVS and LVPS during systole and diastole were measured by cardiac ultrasound in the mouse model of hypertrophic cardiomyopathy. The relative expression of ANP, BNP, beta-MHC, CCL11 and GDF11 in cardiomyocytes or heart tissue of mice was detected by qPCR or Western blot. 3'- UTR luciferase reporter assay was utilized to examine the relationship between GDF11 and the expression of CCL11. RESULTS: The expression of ANP, BNP, and beta-MHC in mouse cardiomyocytes was significantly increased after the cells were treated with 800 nM ANG II, which was utilized in the following cell experiments. After ANG II treatment, 0.2 ng/ml GDF11 group displayed the highest inhibition of expression of ANP, BNP and beta-MHC in mouse cardiomyocytes, whereas 50 ng/ml CCL11 group displayed the highest stimulation of the expression. GDF11 at 10 ng/ml significantly decreased the expression of CCL11 in mouse cardiomyocytes as compared to the control group. Mice treated with ANG II had increased thickness of IVS and LVPS during both systole and diastole, which was significantly attenuated by GDF11 overexpression. GDF11 overexpression attenuated the increase in expression of ANP, BNP and beta-MHC in the mice model of hypertrophic cardiomyopathy. The relative serum concentration of GDF11 was markedly decreased, and CCL11 was dramatically increased in mice with hypertrophic cardiomyopathy. GDF11 overexpression restored the serum concentration of GDF11 and CCL11 in the mice model of hypertrophic cardiomyopathy. In addition, GDF11 interference group had markedly increased expression of CCL11, whereas GDF11 overexpression group had significantly decreased expression of CCL11 in luciferase reporter assay. CONCLUSIONS: GDF11 attenuated ANG II-induced hypertrophic cardiomyopathy and expression of ANP, BNP and beta-MHC through down-regulating CCL11 in mice.

miR-487b mitigates chronic heart failure through inhibition of the IL-33/ST2 signaling pathway.

We investigated the effects of microRNA-587b (miR-487b) in a rat model of chronic heart failure (CHF). Wistar rats were assigned to 10 groups (n=8 per group). Expression of interleukin-33 (IL-33), somatostatin 2 (ST2), IL-6, and TNF-α was higher in the CHF group than the control group. In the CHF, negative control (NC) for si-IL-33, NC for miR-487b mimic, NC for miR-487b inhibitor, and miR-487b inhibitor + si IL-33 groups, as compared to the blank and sham groups: steroid binding protein (SBP), D binding protein (DBP), left ventricular systolic pressure (LVSP), ± dp/dtmax, and superoxide dismutase (SOD) were all lower; myocardial fibrosis, MDA, left ventricular end-diastolic pressure (LVEDP), myocardial apoptosis rate, IL-6, and TNF-α were all higher; levels of IL-33 and ST2 mRNA and protein were higher; and levels of miR-487b were lower. Levels of IL-33 and ST2 mRNA and protein were lower, and SBP, DBP, LVSP, ± dp/dtmax, and SOD were higher in the miR-487b mimic and si-IL-33 groups than the CHF group. Expression of miR-487b was increased in the miR-487b mimic group, and expression of IL-33 and ST2 were increased and expression of miR-487b was decreased in the miR-487b inhibitor group. MiR-487b reduces apoptosis, inflammatory responses, and fibrosis in CHF by suppressing IL-33 through inhibition the IL-33/ST2 signaling pathway.

miR-26b-5p regulates hypoxia-induced phenotypic switching of vascular smooth muscle cells via the TGF-ß/Smad4 signaling pathway.

Hypoxia contributes to the phenotypic switch of vascular smooth muscle cells (VSMCs). Various microRNAs (miRNAs) participate in this process as post­transcriptional regulators, however the mechanism remains unclear. In the present study, mouse VSMCs (mVSMCs) harvested from aortas were cultured in normoxic and hypoxic conditions, and the mRNA levels of miR-26b-5p, desmin, H­caldesmon and smoothelin were quantified using reverse transcription­quantitative polymerase chain reaction. Following treatment with a miR­26b­5p antagonist (agomir) or non­targeting control (scramble), the cell areas of normoxic and hypoxic mVSMCs were analyzed by immunofluorescence staining. In addition, the protein expression levels of collagen Iα, Smad2/phosphorylated (p)­Smad2, Smad3/p­Smad3 and Smad4 were determined by western blotting. Potential miRNA26b­5p binding sequences in the 3'­untranslated region (UTR) of Smad4 were investigated, and the distribution of Smad4 in mVSMCs was visualized using immunofluorescence methods. Hypoxic mVSMCs exhibited a significant downregulation miR­26b­5p, upregulation of hypoxia inducible factor­1α mRNA and suppression of desmin, H­caldesmon and smoothelin mRNA levels. Additionally, miR­26b­5p agomir reduced the cell area and decreased collagen Iα expression levels in hypoxic mVSMCs compared with normoxic mVSMCs transfected with agomir, and the area was comparable with those of normoxic mVSMCs transfected with agomir or scramble. Furthermore, miR­26b­5p suppressed Smad4 expression in hypoxic mVSMCs, but did not change the expression levels of Smad2 and Smad3, p­Smad2 and p­Smad3, however p­Smad2 and p­Smad3 levels were upregulated in response to hypoxic stimuli. Additionally, the miR­26b­5p agomir caused weak immunoreactivity with Smad4 in hypoxic mVSMCs. The binding motif of miR­26b­5p in the Smad4 3'­UTR was identified as UACUUGA at position 978-984. These findings suggest that miR­26b­5p regulates hypoxia­induced phenotypic switching of VSMCs via the transforming growth factor ß/Smad4 signaling pathway.

Cardioprotective effect of notoginsenoside R1 in a rabbit lung remote ischemic postconditioning model via activation of the TGF-ß1/TAK1 signaling pathway.

Pharmacological postconditioning using cardioprotective agents is able to reduce myocardial infarct size. Notoginsenoside R1 (NG-R1), a phytoestrogen isolated from Panax notoginseng saponins (PNS), is considered to have anti-oxidative and anti-apoptotic properties. However, its cardioprotective properties and underlying mechanisms remain largely unknown. The aim of the present study was to determine the cardioprotective and anti-apoptotic effects of NG-R1 in an ischemia-reperfusion (IR)-induced myocardial injury rabbit model. A total of 45 Japanese big-ear rabbits were equally randomized to three groups: Control group, remote ischemic postconditioning (RIP) group and NG-R1 intervention group. At the endpoint of the experiment, the animals were sacrificed to remove myocardial tissues for the detection of transforming growth factor (TGF)-ß1-TGF-ß activated kinase 1 (TAK1) pathway-related proteins by immunohistochemistry and western blot analysis, the activities of caspase-3, -8 and -9 in myocardial cells by fluorometric assay, and the apoptosis of myocardial cells by terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling. Right and left lung tissues were stained with hematoxylin and eosin (H&E) to observe the severity of injury. NG-R1 treatment reduced the activity of superoxide dismutase, increased the content of malondialdehyde, reduced the activities of caspase-3, -8 and -9, and inhibited the apoptosis of myocardial cells in rabbits undergoing RIP. In addition, the expression of TGF-ß1-TAK1 signaling pathway-related proteins was downregulated following NG-R1 intervention. H&E staining of bilateral lung tissues showed that cell morphology was generally intact without significant alveolar congestion, and there was no significant difference among the three groups. These results indicate that NG-R1 protects the heart against IR injury, possibly by inhibiting the activation of the TGF-ß1-TAK1 signaling pathway and attenuating apoptotic stress in the myocardium.

miR-103 Regulates Oxidative Stress by Targeting the BCL2/Adenovirus E1B 19 kDa Interacting Protein 3 in HUVECs.

Oxidative stress plays a critical role in cardiovascular diseases. Salidroside, a glycoside from Rhodiola rosea, has been used as an antioxidative therapy for oxidative injury in cardiac diseases. However, the mechanism underlying its antioxidant effect needs to be elucidated. Treatment of HUVECs with H2O2 significantly decreased the expression of miR-103 in a dose- and time-dependent manner, whereas pretreatment with salidroside significantly inhibited this decrease. Subsequent analysis showed that overexpression of miR-103 abrogated cell activity and ROS production induced by H2O2. Bcl2/adenovirus E1B 19 kDa interacting protein 3 (BNIP3) was determined to be a novel miR-103 target in HUVECs. Interestingly, H2O2 treatment upregulated BNIP3 expression; in turn, this effect was inhibited by pretreatment with salidroside. Further studies confirmed that the knockdown of BNIP3 enhanced cell activity and suppressed the ROS production induced by H2O2. These results demonstrated for the first time that salidroside protects HUVECs in part by upregulating the expression of miR-103, which mediates BNIP3 downregulation and plays an important role in the cytoprotective actions.

Direct ambulance transport to catheterization laboratory reduces door-to-balloon time in patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention: the DIRECT-STEMI study.

BACKGROUND: Primary percutaneous coronary intervention (PCI) has been clearly identified as the first therapeutic option for patients with acute ST-segment elevation myocardial infarction (STEMI). The importance of reducing door-to-balloon (D2B) time has gained increased recognition. This study aimed to assess the feasibility, safety and efficacy of the strategy of direct ambulance transportation of patients with acute STEMI to catheterization lab to receive primary PCI. METHODS: The study population included 141 consecutive patients with chest pain and ST-segment elevation who were admitted to the catheterization laboratory directly by the ambulance and underwent primary PCI (DIRECT group). Another 145 patients with STEMI randomly selected from the PCI database, were served as control group (conventional group); they were transported to catheterization laboratory from emergency room (ER). The primary endpoint of D2B time, and secondary endpoint of in-hospital and 30-day major adverse cardiac events (MACE, including death, non-fatal reinfarction, and target vessel revascularization) were compared. RESULTS: Baseline and procedural characteristics between the two groups were comparable, except more patients in the DIRECT group presented TIMI 0-1 flow in culprit vessel at initial angiogram (80.1% and 73.8%, P = 0.04). Comparing to conventional group, the primary endpoint of D2B time was reduced ((54 ± 18) minutes and (112 ± 55) minutes, P < 0.0001) and the percentage of patients with D2B < 90 minutes was increased in the DIRECT group (96.9% and 27.0%, P < 0.0001). The success rate of primary PCI with stent implantation with final Thrombolysis in Myocardial Infarction (TIMI) 3 flow was significantly higher in the DIRECT group (93.8% and 85.2%, P = 0.03). Although no significant difference was found at 30-day MACE free survival rate between the two groups (95.0% and 89.0%, P = 0.06), a trend in improving survival status in the DIRECT group was demonstrated by Kaplan-Meier analysis. CONCLUSION: Direct ambulance transport of STEMI patients to the catheterization laboratory could significantly reduce D2B time and improve success rate of primary PCI and 30-day clinical outcomes.