scholarly journals Automated synthesis and preliminary evaluation of [18F]FDPA for cardiac inflammation imaging in rats after myocardial infarction

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Tiantian Mou ◽  
Jing Tian ◽  
Yi Tian ◽  
Mingkai Yun ◽  
Junqi Li ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Time Window ◽  
Inflammatory Cells ◽  
Translocator Protein ◽  
Automated Synthesis ◽  
Preliminary Evaluation ◽  
Synthesis Time ◽  
Cardiac Inflammation ◽  
Inflammation Imaging ◽  
Radiochemical Yields

Abstract A translocator protein 18 kDa targeted radiotracer, N,N-diethyl-2-(2-(4-[18F]fluorophenyl)-5,7-dimethylpyrazolo[1,5-a] pyrimidin-3-yl) acetamide ([18F]FDPA), was automated synthetized and evaluated for cardiac inflammation imaging. Various reaction conditions for an automated synthesis were systematically optimized. MicroPET/CT imaging were performed on normal rats and rats with myocardial infarction (MI). Normalized SUV ratios of [18F]FDPA to [13N]NH3 (NSRs) in different regions were calculated to normalize the uptake of [18F]FDPA to perfusion. The amount of TBAOMs and the volume/proportion of water were crucial for synthesis. After optimization, the total synthesis time was 68 min. The non-decay corrected radiochemical yields (RCYs) and molar activities were 19.9 ± 1.7% and 169.7 ± 46.5 GBq/μmol, respectively. In normal rats, [18F]FDPA showed a high and stable cardiac uptake and fast clearance from other organs. In MI rats, NSRs in the peri-infarct and infarct regions, which were infiltrated with massive inflammatory cells revealed by pathology, were higher than that in the remote region (1.20 ± 0.01 and 1.08 ± 0.10 vs. 0.89 ± 0.05, respectively). [18F]FDPA was automated synthesized with high RCYs and molar activities. It showed a high uptake in inflammation regions and offered a wide time window for cardiac imaging, indicating it could be a potential cardiac inflammation imaging agent.

scholarly journals Optimised GMP-compliant production of [18F]DPA-714 on the Trasis AllinOne module

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Klaudia A. Cybulska ◽  
Vera Bloemers ◽  
Lars R. Perk ◽  
Peter Laverman
Keyword(s):  
Significant Degree ◽  
Translocator Protein ◽  
Positron Emission ◽  
Leaving Group ◽  
Inflammatory Processes ◽  
Single Production ◽  
Translocator Protein 18 Kda ◽  
Radiochemical Yields ◽  
Specific Ligand

Abstract Background The translocator protein 18 kDa is recognised as an important biomarker for neuroinflammation due to its soaring expression in microglia. This process is common for various neurological disorders. DPA-714 is a potent TSPO-specific ligand which found its use in Positron Emission Tomography following substitution of fluorine-19 with fluorine-18, a positron-emitting radionuclide. [18F]DPA-714 enables visualisation of inflammatory processes in vivo non-invasively. Radiolabelling of this tracer is well described in literature, including validation for clinical use. Here, we report significant enhancements to the process which resulted in the design of a fully GMP-compliant robust synthesis of [18F]DPA-714 on a popular cassette-based system, Trasis AllinOne, boosting reliability, throughput, and introducing a significant degree of simplicity. Results [18F]DPA-714 was synthesised using the classic nucleophilic aliphatic substitution on a good leaving group, tosylate, with [18F]fluoride using tetraethylammonium bicarbonate in acetonitrile at 100∘C. The process was fully automated on a Trasis AllinOne synthesiser using an in-house designed cassette and sequence. With a relatively small precursor load of 4 mg, [18F]DPA-714 was obtained with consistently high radiochemical yields of 55-71% (n=6) and molar activities of 117-350 GBq/µmol at end of synthesis. With a single production batch, starting with 31-42 GBq of [18F]fluoride, between 13-20 GBq of the tracer can be produced, enabling multi-centre studies. Conclusion To the best of our knowledge, the process presented herein is the most efficient [18F]DPA-714 synthesis, with advantageous GMP compliance. The use of a Trasis AllinOne synthesiser increases reliability and allows rapid training of production staff.

scholarly journals Mitochondrial DNA as an inflammatory mediator in cardiovascular diseases

2018 ◽  
Vol 475 (5) ◽  
pp. 839-852 ◽  
Author(s):  
Hiroyuki Nakayama ◽  
Kinya Otsu
Keyword(s):  
Mitochondrial Dna ◽  
Inflammatory Responses ◽  
Inflammatory Cells ◽  
Nuclear Factor Κb ◽  
Sterile Inflammation ◽  
Microbial Infection ◽  
Cellular Functions ◽  
Radical Oxygen Species ◽  
Cardiac Inflammation ◽  
Contraction And Relaxation

Mitochondria play a central role in multiple cellular functions, including energy production, calcium homeostasis, and cell death. Currently, growing evidence indicates the vital roles of mitochondria in triggering and maintaining inflammation. Chronic inflammation without microbial infection — termed sterile inflammation — is strongly involved in the development of heart failure. Sterile inflammation is triggered by the activation of pattern recognition receptors (PRRs) that sense endogenous ligands called damage-associated molecular patterns (DAMPs). Mitochondria release multiple DAMPs including mitochondrial DNA, peptides, and lipids, which induce inflammation via the stimulation of multiple PRRs. Among the mitochondrial DAMPs, mitochondrial DNA (mtDNA) is currently highlighted as the DAMP that mediates the activation of multiple PRRs, including Toll-like receptor 9, Nod-like receptors, and cyclic GMP–AMP synthetase/stimulator of interferon gene pathways. These PRR signalling pathways, in turn, lead to the activation of nuclear factor-κB and interferon regulatory factor, which enhances the transcriptional activity of inflammatory cytokines and interferons, and induces the recruitment of inflammatory cells. As the heart is an organ comprising abundant mitochondria for its ATP consumption (needed to maintain constant cyclic contraction and relaxation), the generation of massive amounts of mitochondrial radical oxygen species and mitochondrial DAMPs are predicted to occur and promote cardiac inflammation. Here, we will focus on the role of mtDNA in cardiac inflammation and review the mechanism and pathological significance of mtDNA-induced inflammatory responses in cardiac diseases.

scholarly journals Attenuation of myocardial injury in mice with functional deletion of the circadian rhythm gene mPer2

2010 ◽  
Vol 298 (3) ◽  
pp. H1088-H1095 ◽  
Author(s):  
Jitka A. I. Virag ◽  
Jessica L. Dries ◽  
Peter R. Easton ◽  
Amy M. Friesland ◽  
Jon H. DeAntonio ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Cardiovascular Disease ◽  
Circadian Rhythm ◽  
Contractile Function ◽  
Myocardial Infarct ◽  
Inflammatory Cells ◽  
Diurnal Rhythms ◽  
Cardiomyocyte Hypertrophy ◽  
Wild Type ◽  
Infarct Zone

Variations in circadian rhythms are evident in the incidence of cardiovascular disease, and the risk of cardiovascular events increases when rhythms are disrupted. The suprachiasmatic nucleus is the central circadian pacemaker that regulates the daily rhythm of peripheral organs. Diurnal rhythms have more recently been shown to exist in myocardial tissue and are involved in metabolism and contractile function. Thus we sought to determine whether the functional deletion of the circadian rhythm mouse periodic gene 2 (mPer2) would protect the heart against ischemic injury. Nonreperfused myocardial infarction was induced in anesthetized, ventilated C57 ( n = 17) and mPer2 mutant (mPer2-M; n = 15) mice via permanent ligation of the left anterior descending coronary artery. At 4 days post-myocardial infarction, we observed a 43% reduction of infarct area in mPer2-M mice compared with wild-type mice. This is coincident with 25% less macrophage infiltration, 43% higher capillary density, 17% increase in hypertrophy, and 15% less cardiomyocyte apoptosis in the infarct zone. Also, matrix metalloproteinase-9 was expressed in inflammatory cells in both groups, but total protein was 40% higher in wild-type mice, whereas it was not elevated in mPer2-M mice in response to injury. The functional deletion of the mPer2 gene reduces the severity of myocardial infarct injury by limiting the inflammatory response, reducing apoptosis, and inducing cardiomyocyte hypertrophy, thus preserving cardiac function. These findings collectively imply that the disruption of the circadian clock gene mPer2 is protective. Understanding the interactions between circadian rhythm genes and cardiovascular disease may provide insights into potential preventative and therapeutic strategies for susceptible populations.

scholarly journals Role of cytokines in myocardial ischemia and reperfusion

1997 ◽  
Vol 6 (3) ◽  
pp. 175-183 ◽  
Author(s):  
H. S. Sharma ◽  
D. K. Das
Keyword(s):  
Myocardial Infarction ◽  
Growth Factor ◽  
Reperfusion Injury ◽  
Ischemia Reperfusion Injury ◽  
Myocardial Dysfunction ◽  
Ischemia Reperfusion ◽  
Membrane Damage ◽  
Inflammatory Cells ◽  
Myocardial Ischemia And Reperfusion ◽  
Tnf Α

Mediators of myocardial inflammation, predominantly cytokines, have for many years been implicated in the healing processes after infarction. In recent years, however, more attention has been paid to the possibility that the inflammation may result in deleterious complications for myocardial infarction. The proinflammatory cytokines may mediate myocardial dysfunction associated with myocardial infarction, severe congestive heart failure, and sepsis. A growing body of literature suggests that inflammatory mediators could play a crucial role in ischemia–reperfusion injury. Furthermore, ischemia–reperfusion not only results in the local transcriptional and translational upregulation of cytokines but also leads to tissue infiltration by inflammatory cells. These inflammatory cells are a ready source of a variety of cytokines which could be lethal for the cardiomyocytes. At the cellular level it has been shown that hypoxia causes a series of well documented changes in cardiomyocytes that includes loss of contractility, changes in lipid metabolism and subsequent irreversible cell membrane damage leading to cell death. For instance, hypoxic cardiomyocytes produce interleukin-6 (IL-6) which could contribute to the myocardial dysfunction observed in ischemia reperfusion injury. Ischemia followed by reperfusion induces a number of other multi-potent cytokines, such as IL-1, IL-8, tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1) as well as an angiogenic cytokine/ growth factor, vascular endothelial growth factor (VEGF), in the heart. Intrestingly, these multipotent cytokines (e.g. TNF-α) may induce an adaptive cytoprotective response in the reperfused myocardium. In this review, we have included a number of cytokines that may contribute to ventricular dysfunction and/or to the cytoprotective and adaptive changes in the reperfused heart.

scholarly journals Delayed PCI 12 Hours after the Onset of Symptoms Is Associated with Improved Outcomes for Patients with ST-Segment Elevation Myocardial Infarction: A Real-World Study

2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Wen-Juan Xiu ◽  
Hai-Tao Yang ◽  
Ying-Ying Zheng ◽  
Yi-Tong Ma ◽  
Xiang Xie
Keyword(s):  
Myocardial Infarction ◽  
Real World ◽  
Time Window ◽  
Therapy Group ◽  
Trial Registration ◽  
St Segment Elevation ◽  
Medication Therapy ◽  
Segment Elevation Myocardial Infarction ◽  
St Segment ◽  
Significant Difference

Background. Primary percutaneous coronary intervention (PPCI) plays a pivotal role in the treatment of ST-segment elevation myocardial infarction (STEMI). However, it remains controversial whether PCI delayed beyond the recommended time window of 12 h after the onset of symptoms is applicable to STEMI. Objective. The acute myocardial infarction (AMI) registration study in Xinjiang, China, is a real-world clinical trial (retrospective cohort study) that includes hospitalized patients. The purpose of this study was to compare delayed PCI and medication therapy beyond the recommended time window of 12 h after the onset of symptoms on the outcomes of STEMI patients. Methods and Results. From May 2012 to December 2015, a total of 1072 STEMI patients received delayed PCI (n=594) or standard medication therapy (MT) (n=478) more than 12 h after the onset of symptoms. The number of all-cause deaths in the delayed PCI group and that in the MT group were 55 (9.3%) and 138 (28.9%), respectively, and a significant difference between the groups was indicated for this variable (P<0.001). The number of cardiac deaths in the delayed PCI group and that in the medication therapy group were 47 (7.9%) and 120 (25.1%), respectively, and a significant difference between the groups was indicated for this variable (P<0.001). We also found that the MACE incidence in the delayed PCI group was significantly higher than it was in the MT group (32.2% versus 43.5%, P<0.001). Propensity score matching (PSM) analyses remained significant differences between the delayed PCI group and the MT group, respectively, in all-cause deaths (9.3% versus 25.8%, P<0.001) and cardiac death (8.7% versus 21.6%, P<0.001). Conclusion. Compared to medication therapy, PCI for STEMI delayed beyond 12 h after the onset of symptoms can better reduce mortality and the incidence of MACEs. Trial Registration. This study is registered with the following: Trial Registration: clinicaltrials.gov; Identifier: NCT02737956.

scholarly journals Autotaxin inhibition reduces cardiac inflammation and mitigates adverse cardiac remodeling after myocardial infarction

2020 ◽  
Vol 149 ◽  
pp. 95-114
Author(s):  
Himi Tripathi ◽  
Ahmed Al-Darraji ◽  
Mohamed Abo-Aly ◽  
Hsuan Peng ◽  
Elica Shokri ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Cardiac Remodeling ◽  
Cardiac Inflammation

scholarly journals Coronary inflammation: why searching, how to identify and treat it

2020 ◽  
Vol 22 (Supplement_E) ◽  
pp. E121-E124
Author(s):  
Francesco Prati ◽  
Valeria Marco ◽  
Giulia Paoletti ◽  
Mario Albertucci
Keyword(s):  
Myocardial Infarction ◽  
Smooth Muscle ◽  
High Risk ◽  
Personalized Medicine ◽  
Smooth Muscle Cells ◽  
High Sensitivity ◽  
Inflammatory Cells ◽  
Muscle Cells ◽  
Atherosclerotic Lesions ◽  
The Cantos

Abstract Inflammation plays an important role in the development of atherosclerotic lesions. A variety of stimuli promote atherosclerosis, including increased LDL cholesterol in blood, exposure to tobacco, diabetes mellitus, hypertension, or rheological stress. Inflammatory cells have an established role in the growth of atherosclerotic lesions. Macrophages recognize and internalise ox-LDL to eventually become lipid-laden foam cells, the hallmark cellular component of atheroma. Infiltrating CD4-T cells have a role too, by interacting with ox-LDL and other antigens. Cytokines secreted by inflammatory cells stimulate smooth muscle cells migration whilst macrophages produce metalloprotease that lead to fibrous cap rupture. The necrotic debris of died macrophages and smooth muscle cells help to continue the inflammatory process. The inflammatory response can also directly activate platelets and promote thrombus formation at the surface of complicated coronary plaques. The CANTOS trial can be waived as an innovative study promoting a novel approach of personalized medicine. In patients with previous myocardial infarction, high-sensitivity C-reactive protein level of 2 mg and normal LDL level (&lt;70 mg/dL), canakinumab a therapeutic monoclonal antibody targeting interleukin-1β, at a dose of 150 mg every 3 months, led to a significant reduction of the primary efficacy end point: nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death at 48 months. Based on the CANTOS results, patients on statins and residual inflammatory risk as assessed by means of a high-sensitivity CRP &gt;2 mg/l at baseline have a high risk of future cardiac events, comparable to that of statin-treated patients with suboptimal cholesterol LDL level. The inhibition of interleukin-1β by means of canakinumab, which is only one of many potential anti-inflammatory pathways, open new perspectives, showing that a selective inhibition of the inflammatory pathway may be beneficial in reducing cardiovascular risk. In a process of personalized medicine, there is need to accurately identify patients at high risk of events, to be treated with potent statins or anti-inflammatory drugs. Perhaps in the near future a more specific assessment of coronary inflammations, possibly obtained with imaging modalities (either invasive or non-invasive), will better select patients at risk of events. In this scenario, in the setting of secondary prevention, OCT may serve the scope of identifying vulnerable plaques with local aggregates of inflammatory cells. Future studies are needed to understand the clinical effectiveness of strategies based on invasive coronary assessment.

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