Risultati per: I microRNA: nuovi bersagli per il trattamento dell’asma

Circulation, Volume 150, Issue Suppl_1, Page A4137448-A4137448, November 12, 2024. Purpose:MicroRNAs (miRs) have been proposed as biomarkers of myocardial infarction (MI), but prior evidence has demonstrated that heparin, commonly administered to patients presenting with MI, inhibits amplification during quantitative PCR (qPCR). The purpose of this study was to determine whether qPCR amplification of miRs is reduced in plasma of patients receiving heparin and if heparinase reverses this effect.Methods:Blood samples were collected and plasma recovered from patients with normal coronary arteries who had undergone CT coronary angiography (N=5) or who had received intravenous heparin at the time of invasive coronary angiography(N=8). Blood was also collected at the time of invasive coronary angiography from patients presenting with ST elevation MI (N=9). RT-qPCR was performed to quantify levels of 84 cardiac miRs, and Cel-miR-39-3p was utilized as a spike-in control. MiR qPCR was also performed following the addition of heparinase to plasma from 2 patients without MI treated with heparin and 2 patients presenting with MI who had received heparin.Results:Mean age of patients was 57 years, and 55% of patients were male. As compared with control patients, the cycle number for cel-miR-39-3p was significantly increased for patients receiving heparin (Figure 1a). No difference was seen in levels of cel-39-3p in heparin-treated patients with respect to the presence or absence of MI. Cel-miR-39-3p cycle times decreased when heparinase was added to samples from heparin-treated patients (Figure 1b). In contrast, heparin did not increase cycle times in any of the cardiac miRs tested, and cycle times decreased even further for miRs 499a-5p and 208b-3p in patients with MI (Figure 2).Conclusions:Systemic heparin treatment inhibits qPCR amplification of cel-mir-39-3p but does not inhibit endogenous miR amplification under these conditions. MiRs 499a-5p and 208b-3p are potentially important candidates for MI detection and quantification.

Circulation, Volume 150, Issue Suppl_1, Page A4142024-A4142024, November 12, 2024. Introduction:Dysferlinopathy, a subgroup within muscular dystrophies, is an autosomal recessive myopathy that entails a spectrum of progressive muscle degeneration with a pathogenic mechanism of impaired sarcolemma. Its genetic etiology is rooted in mutations in the DYSF gene at Chromosome 2p13. The DYSF gene encodes for dysferlin, a type II transmembrane protein prominently expressed in skeletal muscle and cardiac tissue. Dysferlin plays a pivotal role in calcium-dependent membrane repair and regulate macrophage activation in skeletal muscles. MicroRNAs (miRNAs), highly conserved non-coding RNA transcripts under 25 nucleotides, modulate translational repression via mRNA degradation. Reduced expression of miR-486, a muscle enriched miRNA, has been correlated with the disease severity in Duchenne muscular dystrophy. However, the expression level of miR-486 and its role has not been elucidated in dysferlinopathy.Hypothesis:We hypothesized that miR-486 expression is differentially expressed in dysferlin-deficient skeletal muscle, function as a regulator of cell cycle kinetics, differentiation, and is essential for the sarcolemma repair machinery.Methods:Tissue expression analysis of miR-486 was performed across ten mice tissues. Subsequently, miR-486 was overexpressed and silenced in both wild type and dysferlin deficient murine myoblasts (C2C12 cells) via cellular transfection (n=3). Differential expression of miR-486 levels and various cell cycle genes were validated using qRT-PCR. Myoblast fusion assay, along with immunohistochemistry was undertaken to determine cellular differentiation. Bioinformatics approach was undertaken for pathway analysis of miR486 in dystrophic muscles.Results:We confirmed that miR486 is myogenic, demonstrated by highest expression in skeletal muscles. We found reduced expression of miR486 by more than two folds in dysferlin-deficient myoblasts compared to the wild-type. Overexpression of miR-486 increased Ki-67 and MCM2 expression in wild-type myoblasts, indicating its pro-proliferative role.Conclusion:The results thus far suggest that dysferlinopathy is associated with aberrant expression of miR-486, which plays a role in regulating myoblast proliferation. We are currently focused on elucidating how miR-486 influences myoblast differentiation and characterizing the underlying molecular mechanisms by quantifying the gene expression changes driven by modulation of miR-486.

Circulation, Volume 150, Issue Suppl_1, Page A4117256-A4117256, November 12, 2024. Background:Coronary microembolization (CME) commonly occurs during PCI in acute coronary syndrome, leading to myocardial damage. The purpose of this study is to explore the effects of CME on autophagy-related microRNAs and protein pathways, and to identify possible mechanisms of myocardial injury caused by CME.Methods:This study randomly divided rats into 6 groups: sham and CME1h, 3h, 6h, 9h, 12h groups. A rat model of CME was established by injecting autologous microthrombi into the left ventricle. Echocardiography and HE staining were performed to evaluate myocardial infarct size in each group. The expression of microRNA-144-3p and microRNA-214-3p, LC3-II, p62/SQSTM1, phosphatase, and PTEN was detected.Results:Compared with the sham group, LVEF and LVFS decreased,LVESD increased (P

Circulation, Volume 150, Issue Suppl_1, Page A4129523-A4129523, November 12, 2024. Introduction:Patients with diabetes are at higher risk of chronic limb-threatening ischemia (CLTI), a severe form of peripheral artery disease (PAD) causing restricted blood flow to the lower limbs due, in part, to impaired angiogenesis. However, the role of microRNAs (miRNAs) in diabetic CLTI remains poorly understood. By integrating plasma miRNA sequencing data from PAD patients with diabetes with a diabetic CLTI mouse model, we have recently identified the conserved miRNA miR-1282 that is in cis-antisense orientation to SERF2, a gene associated with amyloid aggregation. Therefore, we hypothesize that miR-1282 orchestrates endothelial angiogenesis and proteostasis during diabetic CLTI.Methods:Using miR-1282 overexpression or SERF2 knockdown studies, we characterized mouse orthologs of human miR-1282 and SERF2 for angiogenesis, apoptosis, protein aggregation, and oxidative stress in diabetic mouse skeletal muscle endothelial cells (ECs). In vivo, miR-1282 mimics were delivered intramuscularly to assess their impact on blood flow recovery, angiogenesis, and protein aggregation. Mechanistic insights in ECs were gained via RNA-seq, predictive algorithms, and proteomic analyses.Results:miR-1282 inhibited the expression of its cis-antisense target SERF2 by 98%. miR-1282 is a hypoxia-induced endothelial-enriched miRNA, and its expression was inversely correlated with SERF2 expression. miR-1282 levels were markedly reduced after femoral artery ligation (FAL) in diabetic db/db mice. Overexpression of miR-1282 or SERF2 knockdown enhanced angiogenesis and reduced protein aggregation, apoptosis, and oxidative stress in both normal and hypoxic conditions in vitro. Delivery of miR-1282 mimics in db/db mice improved blood flow recovery by 108% and angiogenesis by 98%, and reduced protein aggregation by 48% and tissue necrosis. Coupling RNA-seq profiling and prediction algorithms of ECs upon miR-1282 overexpression or SERF2 knockdown revealed EREG, BAG5, CASP3, ARG1, and HSP90AA1 as potential downstream regulators. Pathway enrichment analysis implicated inhibition of endothelial apoptosis, ER stress, and protein stability among the most dysregulated processes.Conclusion:A novel mouse ortholog of human miR-1282 augments endothelial functions and diminishes protein aggregation in diabetic CLTI via suppression of its cis-antisense target SERF2. These findings uncover new potential therapeutic targets in treating diabetic CLTI.

Bene lo studio di fase III

‘In molti casi otteniamo la guarigione, ma la prevenzione è fondamentale’

Si ricorre più spesso a cure per la sterilità

Uno studio su Science dimostra come questi accessori possano essere utilizzati per valutare le condizioni metaboliche e respiratorie di una persona