scholarly journals LRP6 modulates the phosphorylation of Cx43 via Gαs in ventricular tachycardia of myocardial infarction

Author(s):  
Xuming Zhang ◽  
Ya-ling Liu ◽  
Ying Cai ◽  
Ying Hao ◽  
Sheng Kang

Abstract Background Ventricular tachycardia (VT) and ventricular fibrillation are the most causes of early death in patients with myocardial infarction (MI). This study was aimed to explore whether LRP6 and its upstream genes circRNA1615 and miR-152-3p modulated the phosphorylation of Connexin-43 (Cx43) via Gαs in ventricular tachycardia of MI. Method we constructed the hypoxia cardiomyocyte model and AMI mice, and explored the modulation relationship of LRP6 and its upstream genes circRNA1615 and miR-152-3p. In addition, the immunoblot analysis with monoclonal and polyclonal antibodies were used to detect whether LRP6 and Cx43 were phosphorylated, further investigated that the LRP6 regulated the phosphorylation of its downstream target Cx43 via G-protein alpha subunit Gαs by using cell transfection, FISH assay, HE staining, RT-qPCR, and Western blot techniques. Result LRP6 mRNA expression was significantly reduced in AMI group compared with the control group. Hypoxia could inhibit the protein and phosphorylation levels of LRP6 and Cx43. The expression of circRNA1615 in AMI mice was significantly decreased, but overexpression of circRNA1615 significantly reversed it. Also overexpression of circRNA1615 could weaken the effect of miR-152-3p mimic, and the miR-152-3p mimic increased the hypoxia injury of LRP6 and Cx43, further LRP6 interference fragments could aggravate hypoxia injury of Cx43. The overexpression of LRP6 could significantly increase the protein level and phosphorylation level of Cx43, but the interference with LRP6 showed the opposite trend. Noticeably, the interference with Gαs weakened the protein and phosphorylation levels of Cx43, however, the interference with LRP6 further inhibited the protein and phosphorylation levels of Cx43. Finally, the transcriptions of circRNA1615 and LRP6 were inhibited in AMI, but the transcription of miR-152-3p was promoted, and the overexpression of circRNA1615 could weaken the damage effect and VT of AMI. Conclusion LRP6 and its upstream genes circRNA1615 and miR-152-3p modulated the phosphorylation of Cx43 via Gαs in ventricular tachycardia of myocardial infarction.

Blood ◽  
2001 ◽  
Vol 97 (12) ◽  
pp. 3721-3726 ◽  
Author(s):  
Ilka Ott ◽  
Martin Andrassy ◽  
Dominik Zieglgänsberger ◽  
Stefanie Geith ◽  
Albert Schömig ◽  
...  

In acute myocardial infarction (AMI), monocyte procoagulant activity is increased and may contribute to the risk for recurrence and other thrombotic events. This study sought to investigate the role tissue factor (TF) and tissue factor pathway inhibitor-1 (TFPI-1) in the regulation of monocyte procoagulant activity in AMI. Serial venous blood samples were obtained from 40 patients with AMI undergoing revascularization by stent placement. Twenty patients with elective stenting for stable angina served as control subjects. TF proteolytic activity was measured with spectrozyme factor Xa (FXa), TF and TFPI-1 surface expression on monocytes by flow cytometry, RNA expression in whole blood by reverse transcription–polymerase chain reaction, and concentrations of plasma prothrombin fragments F1 + 2 by immunoassay. Forty-eight hours after AMI, an increase was found in TF RNA, followed by an increase in TF surface expression by 24% ± 4% and in plasma concentration of F1 + 2 by 103% ± 17% (P < .05). These changes could not be attributed to the intervention because they did not occur in the control group. TFPI-1 RNA and binding to the monocyte surface remained unchanged. FXa generation by monocytes of patients with AMI increased 53.6% ± 9% in the presence of polyclonal antibodies to TFPI-1, indicating that cell-associated TFPI-1 inhibits monocyte TF activity. The increased monocyte procoagulant activity in AMI was caused by an up-regulation of TF that was partially inhibited by surface-bound TFPI-1. Anticoagulant therapy by direct inhibition of TF activity may, thus, be particularly effective in AMI.


1999 ◽  
Vol 82 (07) ◽  
pp. 104-108 ◽  
Author(s):  
Franck Paganelli ◽  
Marie Christine Alessi ◽  
Pierre Morange ◽  
Jean Michel Maixent ◽  
Samuel Lévy ◽  
...  

Summary Background: Type 1 plasminogen activator inhibitor (PAI-1) is considered to be risk factor for acute myocardial infarction (AMI). A rebound of circulating PAI-1 has been reported after rt-PA administration. We investigated the relationships between PAI-1 levels before and after thrombolytic therapy with streptokinase (SK) as compared to rt-PA and the patency of infarct-related arteries. Methods and Results: Fifty five consecutive patients with acute MI were randomized to strep-tokinase or rt-PA. The plasma PAI-1 levels were studied before and serially within 24 h after thrombolytic administration. Vessel patency was assessed by an angiogram at 5 ± 1days. The PAI-1 levels increased significantly with both rt-PA and SK as shown by the levels obtained from a control group of 10 patients treated with coronary angioplasty alone. However, the area under the PAI-1 curve was significantly higher with SK than with rt-PA (p <0.01) and the plasma PAI-1 levels peaked later with SK than with rt-PA (18 h versus 3 h respectively). Conversely to PAI-1 levels on admission, the PAI-1 levels after thrombolysis were related to vessel patency. Plasma PAI-1 levels 6 and 18 h after SK therapy and the area under the PAI-1 curve were significantly higher in patients with occluded arteries (p <0.002, p <0.04 and p <0.05 respectively).The same tendency was observed in the t-PA group without reaching significance. Conclusions: This study showed that the PAI-1 level increase is more pronounced after SK treatment than after t-PA treatment. There is a relationship between increased PAI-1 levels after thrombolytic therapy and poor patency. Therapeutic approaches aimed at quenching PAI-1 activity after thrombolysis might be of interest to improve the efficacy of thrombolytic therapy for acute myocardial infarction.


1997 ◽  
Vol 77 (02) ◽  
pp. 248-251 ◽  
Author(s):  
Lena Norlund ◽  
Johan Holm ◽  
Bengt Zöller ◽  
Ann-Kristin Öhlin

SummaryEndothelial dysfunction and haemostatic imbalance are believed to be important aetiological factors in the development of acute coronary syndromes. Thrombomodulin (TM) is an integral membrane protein crucial for normal endothelial function and activation of the protein C anticoagulant pathway. We have investigated the importance of a common C/T dimorphism in the TM gene (nucleotide 1418) for development of premature myocardial infarction (MI). The C/T dimorphism predicts an Ala455 to Val replacement in the sixth EGF-like domain of TM. The dimorphism was investigated in 97 MI survivors and 159 healthy controls. The C allele was significantly more frequent among patients than controls (p = 0.035). The allele frequency for the C allele was 0.82 in the patients and 0.72 in the control group. The plasma concentration of TM was investigated among healthy controls but was not related to the C/T dimorphism. In conclusion, the association of the C allele with premature MI, suggests that the TM gene and the C/T dimorphism may be aetiological factors involved in the pathogenesis of MI. Possibly, the Ala455 to Val replacement may affect the function of the TM molecule and the activation of the protein C anticoagulant pathway.


1997 ◽  
Vol 77 (01) ◽  
pp. 057-061 ◽  
Author(s):  
Dennis W T Nilsen ◽  
Lasse Gøransson ◽  
Alf-Inge Larsen ◽  
Øyvind Hetland ◽  
Peter Kierulf

SummaryOne hundred patients were included in a randomized open trial to assess the systemic factor Xa (FXa) and thrombin inhibitory effect as well as the safety profile of low molecular weight heparin (LMWH) given subcutaneously in conjunction with streptokinase (SK) in patients with acute myocardial infarction (MI). The treatment was initiated prior to SK, followed by repeated injections every 12 h for 7 days, using a dose of 150 anti-Xa units per kg body weight. The control group received unfractionated heparin (UFH) 12,500 IU subcutaneously every 12 h for 7 days, initiated 4 h after start of SK infusion. All patients received acetylsalicylic acid (ASA) initiated prior to SK.Serial blood samples were collected prior to and during the first 24 h after initiation of SK infusion for determination of prothrombin fragment 1+2 (Fl+2), thrombin-antithrombin III (TAT) complexes, fibrinopeptide A (FPA) and cardiac enzymes. Bleeding complications and adverse events were carefully accounted for.Infarct characteristics, as judged by creatine kinase MB isoenzyme (CK-MB) and cardiac troponin T (cTnT), were similar in both groups of patients.A comparable transient increase in Fl+2, TAT and FPA was noted irrespective of heparin regimen. Increased anti-Xa activity in patients given LMWH prior to thrombolytic treatment had no impact on indices of systemic thrombin activation.The incidence of major bleedings was significantly higher in patients receiving LMWH as compared to patients receiving UFH. However, the occurrence of bleedings was modified after reduction of the initial LMWH dose to 100 anti-Xa units per kg body weight.In conclusion, systemic FXa- and thrombin activity following SK-infusion in patients with acute MI was uninfluenced by conjunctive LMWH treatment.


2018 ◽  
Vol 17 (2) ◽  
pp. 24-28
Author(s):  
O. M. Polikutina ◽  
Y. S. Slepynina ◽  
E. D. Bazdyrev ◽  
V. N. Karetnikova ◽  
O. L. Barbarach

Aim. To evaluate the structural and functional changes in the lungs of ST elevation myocardial infarction (STEMI) patients with absence or presence of chronic obstructive lung disease (COPD), and the relation with myocardial dysfunction and systemic inflammation.Material and methods. Totally, 189 STEMI patients included: group 1 — STEMI with COPD of moderate and mild grade, 2 — STEMI with no lung pathology. Groups were comparable by clinical and anamnestic parameters. Assessment of lung function and blood collection were done at 10­12 day of STEMI. For comparison of the parameters representing structural and functional changes in the lungs and comparison of C­reactive protein (CRP), N­terminal pro­brain natriuretic peptide (NT­proBNP) concentration, a control group was formed with no pulmonary pathology, comparable by age and sex with the STEMI patients.Results. In COPD patients, higher values revealed of the parameters representing the part of residual volumes in pulmonary structure. Higher residual volume (RV) was found also in STEMI and no COPD comparing to controls, however the relation RV/TLC (total lung capacity) was not higher than normal range. In both groups there were lower values of diffusion lung capacity (DLCO) comparing to controls. The lowest DLCO found in COPD patients. Concentration of NT­proBNP (H=41,6; p<0,001) and CRP (H=38,6; p<0,001) in COPD was significantly higher in STEMI with no COPD patients than in controls. The negative correlations found for NT­proBNP and CRP with forced expiratory volume 1 sec, FEV/FVC1, DLCO, and positive — with the values of thoracic volume, RV/TLC.Conclusion. In STEMI patients the increase revealed of residual lung volumes. Mostly the level of residual volumes is high in STEMI and COPD patients. There are associations of NT­proBNP and CRP with structural and functional parameters of the lungs regardless of COPD.


2020 ◽  
Vol 11 (3) ◽  
pp. 3251-3260
Author(s):  
Makrand B Mane

Acute Myocardial Infarction (AMI) has become a significant public health issue in developed and developing nations, following extensive diagnostic and management research over recent decades. The study intended to research the prognostic values of inexplicable Hyponatremia in patients with severe STelevation of myocardial infarction, in 100 consecutive patients admitted to Tertiary care hospital. In the analysis, identified patients on admission were diagnosed with or produced Hyponatremia within 72 hours—a lower ejection fraction than those with usual amounts of sodium. The research aimed to evaluate the prognosis significance of Hyponatremia for the estimation of early death in acute ST-elevated myocardial infarction. One hundred straight patients admitted in the Coronary Centre Tertiary Care Facility with severe STelevated myocardial infarction were studied. The data of the study on various risk factors in association with the development of Hyponatremia like as age, sex, use of tobacco, diabetes, hypertension, ejection fraction etc. were analyzed. Thus, the researchers reported that in patients diagnosed with severe ST section escalation, Hyponatremia showed the initial emergence of hyponatremia myocardial infarctions. This condition correlates with the severity of LV dysfunction (in term of LVEF) and can be considered as an individual early death indicator as well as a prediction exacerbates with hyponatremia frequency.


Author(s):  
Tupitsyn V.V. ◽  
Bataev Kh.M. ◽  
Men’shikova A.N. ◽  
Godina Z.N.

Relevance. Information about the cardiovascular diseases risk factors (CVD RF) for in men with chronic lung inflam-matory pathology (CLID) is contradictory and requires clarification. Aim. To evaluate the peculiarities of CVD RF in men under 60 years of age with CLID in myocardial infarction (MI) to improve prevention. Material and methods. The study included men aged 19-60 years old with type I myocardial infarction. Patients are divided into two age-comparable groups: I - the study group, with CLID - 142 patients; II - control, without it - 424 patients. A comparative analysis of the frequency of observation of the main and additional cardiovascular risk fac-tors in groups was performed. Results. In patients of the study group, more often than in the control group we observed: hereditary burden of is-chemic heart disease (40.8 and 31.6%, respectively; p = 0.0461) and arterial hypertension (54.2 and 44.6%; p = 0.0461), frequent colds (24.6 and 12.0%; p = 0.0003), a history of extrasystoles (19.7 and 12.7%; p = 0.04); chronic foci of infections of internal organs (75.4 and 29.5%; p˂0.0001), non-ulcer lesions of the digestive system (26.1 and 14.6%; p = 0.007), smoking (95.1 and 66.3%; p˂0.0001), MI in winter (40.8 and 25.9%; p = 0.006). Less commonly were observed: oral cavity infections (9.2 and 23.6%; p˂0.0001); hypodynamia (74.5 and 82.5%; p = 0.0358), over-weight (44.4 and 55.2%; p = 0.0136), a subjective relationship between the worsening of the course of coronary heart disease and the season of the year (43.7 and 55.2%; p = 0.0173) and MI - in the autumn (14.1 and 21.9%; p = 0.006) period. Conclusions. The structure of CVD RF in men under 60 years of age with CLID with MI is characterized by the pre-dominance of smoking, non-ulcer pathology of the digestive system, frequent pro-student diseases, meteorological dependence, a history of cardiac arrhythmias and foci of internal organ infections. It is advisable to use the listed factors when planning preventive measures in such patients.


2018 ◽  
Vol 33 (2) ◽  
pp. 70-76 ◽  
Author(s):  
A. E. Gombozhapova ◽  
Yu. V. Rogovskaya ◽  
M. S. Rebenkova ◽  
J. G. Kzhyshkowska ◽  
V. V. Ryabov

Purpose. Myocardial regeneration is one of the most ambitious goals in prevention of adverse cardiac remodeling. Macrophages play a key role in transition from inflammatory to regenerative phase during wound healing following myocardial infarction (MI). We have accumulated data on macrophage properties ex vivo and in cell culture. However, there is no clear information about phenotypic heterogeneity of cardiac macrophages in patients with MI. The purpose of the project was to assess cardiac macrophage infiltration during wound healing following myocardial infarction in clinical settings taking into consideration experimental knowledge.Material and Methods. The study included 41 patients with fatal MI type 1. In addition to routine analysis, macrophages infiltration was assessed by immunohistochemistry. We used CD68 as a marker for the cells of the macrophage lineage, while CD163, CD206, and stabilin-1 were considered as M2 macrophage biomarkers. Nine patients who died from noncardiovascular causes comprised the control group.Results. The intensity of cardiac macrophage infiltration was higher during the regenerative phase than during the inflammatory phase. Results of immunohistochemical analysis demonstrated the presence of phenotypic heterogeneity of cardiac macrophages in patients with MI. We noticed that numbers of CD68+, CD163+, CD206+, and stabilin-1+ macrophages depended on MI phase.Conclusion. Our study supports prospects for implementation of macrophage phenotyping in clinic practice. Improved understanding of phenotypic heterogeneity might become the basis of a method to predict adverse cardiac remodeling and the first step in developing myocardial regeneration target therapy.


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