Treatment with recombinant tissue plasminogen activator alters the microRNA expression profiles in mouse brain after acute ischemic stroke

CT perfusion imaging parameters and serum miR-106a-5p predict short- and long-term prognosis in acute cerebral infarction patients after intravenous thrombolysis

BACKGROUND

Some microRNAs have been found to be abnormal in patients with acute cerebral infarction (ACI) after intravenous thrombolysis. This study aimed to measure the expression of miR-106a-5p in ACI patients before and after thrombolytic treatment, and to investigate the prognostic value of miR-106a-5p and computed tomography perfusion imaging (CTPI) parameters in ACI patients receiving thrombolysis.

METHODS

The levels of serum miR-106a-5p were detected by quantitative real-time PCR in 78 ACI patients before thrombolysis, 24 hours after thrombolysis, and 3 months (90 days) after onset. The correlation of miR-106a-5p with continuous variables were analyzed using Pearson correlation analysis. The association of miR-106a-5p and CTPI parameters with prognosis of patients receiving thrombolysis was evaluated by logistic regression analysis. The accuracy and thresholds of miR-106a-5p and CTPI parameters for discriminating patients with unfavorable prognosis after thrombolysis were assessed by receiver operating characteristic analysis.

RESULTS

Serum miR-106a-5p expression was decreased in ACI patient after thrombolysis. Then, significant correlations of miR-106a-5p with National Institutes of Health Stroke Scale and CTPI parameters were found. Moreover, miR-106a-5p, cerebral blood flow (CBF) and cerebral blood volume (CBV), which are 2 CTPI parameters, were independently correlated with short- and long-term prognosis after thrombolysis. Furthermore, miR-106a-5p, CBF and CBV revealed good accuracy in predicting the prognosis of patients after thrombolysis, and their combination showed the best accuracy.

CONCLUSION

Thrombolysis downregulates miR-106a-5p in ACI patients, and miR-106a-5p, CBF and CBV have considerable potentials to predict short- and long-term prognosis in ACI patients receiving intravenous thrombolysis.

MicroRNA-125a-3p Modulate Amyloid β-Protein through the MAPK Pathway in Alzheimer's Disease

BACKGROUND

MicroRNA (miR)-125a-3p is reported to play an important role in some central nervous system diseases, such as Alzheimer's disease (AD). However, a study has not been conducted on the mechanism of miR-125a-3p in the pathological process of AD.

METHODS

First, we assessed the expression of miR-125a-3p in AD cohort. Subsequently, we altered the expressions of miR-125a-3p to assess its role in cell viability, cell apoptosis, amyloid-β (Aβ) metabolism, and synaptic activity. Finally, we identified its potential mechanism underlying AD pathology.

RESULTS

This study unveiled the potential function of miR-125a-3p through modulating amyloid precursor protein processing. Additionally, miR-125a-3p influenced cell survival and activated synaptic expression through the modulation of Aβ metabolism in the mitogen-activated protein kinase (MAPK) pathway via fibroblast growth factor receptor 2.

CONCLUSION

Our study indicates that targeting miR-125a-3p may be an applicable therapy for AD in the future. However, more in vitro and in vivo studies with more samples are needed to confirm these results.

Impacts of circulating microRNAs in exercise-induced vascular remodeling

Cardiovascular adaptation underlies all athletic training modalities, with a variety of factors contributing to overall response during exercise-induced stimulation. In this regard the role of circulating biomarkers is a well-established and invaluable tool for monitoring cardiovascular function. Specifically, novel biomarkers such as circulating cell free DNA and RNA are now becoming attractive tools for monitoring cardiovascular function with the advent of next generation technologies that can provide unprecedented precision and resolution of these molecular signatures, paving the way for novel diagnostic and prognostic avenues to better understand physiological remodeling that occurs in trained versus untrained states. In particular, microRNAs are a species of regulatory RNAs with pleiotropic effects on multiple pathways in tissue-specific manners. Furthermore, the identification of cell free microRNAs within peripheral circulation represents a distal signaling mechanism that is just beginning to be explored via a diversity of molecular and bioinformatic approaches. This article provides an overview of the emerging field of sports/performance genomics with a focus on the role of microRNAs as novel functional diagnostic and prognostic tools, and discusses present knowledge in the context of athletic vascular remodeling. This review concludes with current advantages and limitations, touching upon future directions and implications for applying contemporary systems biology knowledge of exercise-induced physiology to better understand how disruption can lead to pathology.

Emerging Roles of Dysregulated MicroRNAs in Myasthenia Gravis

Myasthenia gravis (MG) is a rare acquired autoimmune neuromuscular disease. Autoantibodies, cellular immunity, complement, and cytokines are involved in the pathogenesis of MG. It is characterized by the dysfunction of neuromuscular junction transmission and skeletal muscle weakness. MicroRNAs (miRNAs) are non-coding small molecule ribonucleic acids that regulate various biological processes (e.g., development, differentiation, and immunity) at the transcriptional and post-transcriptional levels of gene expression. miRNAs play an important regulatory role in the pathogenesis of autoimmune diseases, including MG. In recent studies, the functional mechanisms underlying the role of miRNAs in the pathogenesis of MG have received increasing attention. miRNAs are highly stable and have high specificity in peripheral body fluids. Therefore, the miRNAs in body fluids may represent promising biomarkers for determining the prognosis of MG and the efficacy of treatment. This article reviews the role of miRNAs in the pathogenesis of MG, highlights the potential of miRNAs as new biomarkers for the diagnosis of MG, and deepens our understanding of disease processes.

Increased plasma levels of miR-124-3p, miR-125b-5p and miR-192-5p are associated with outcomes in acute ischaemic stroke patients receiving thrombolysis

BACKGROUND AND AIMS

Circulating microRNAs (miRNAs) have recently emerged as promising biomarkers for acute ischaemic stroke (AIS). However, the expression profiles of miRNAs in AIS patients receiving intravenous thrombolysis, and their associations with outcome have not been investigated.

METHODS

In a prospective cohort study, a total of 84 AIS patients, who received intravenous thrombolysis (21.4% received combined reperfusion therapy) and completed 3 month follow-up visits, were included. Favourable and unfavourable outcomes were defined as modified Rankin Scale (mRS) scores of 0-1 and 2-6, respectively. Plasma samples were collected at 24 h after thrombolysis. We used RNA sequencing to study miRNA profiles in 5 patients with unfavourable outcomes and 5 matched patients with favourable outcomes. Differentially expressed miRNAs were further validated in all cohorts using quantitative real-time polymerase chain reaction assays.

RESULTS

After identification and validation, we found that miR-124-3p, miR-125b-5p and miR-192-5p levels were higher in patients with unfavourable outcomes than in patients with favourable outcomes. Logistic regressions and receiver-operating characteristic curve analyses demonstrated that these altered miRNAs may function as predictive biomarkers for outcome in AIS patients receiving thrombolysis, whether combined with endovascular thrombectomy or not. In addition, miR-124-3p and miR-125b-5p were closely associated with stroke severity.

CONCLUSIONS

A set of circulating microRNAs (miR-124-3p, miR-125b-5p and miR-192-5p) are associated with unfavourable 3 month outcomes and might have clinical utility in AIS patients receiving thrombolysis.

The Emerging Role of Epigenetics in Cerebral Ischemia

Despite great progresses in the treatment and prevention of ischemic stroke, it is still among the leading causes of death and serious long-term disability all over the world, indicating that innovative neural regenerative and neuroprotective agents are urgently needed for the development of therapeutic approaches with greater efficacy for ischemic stroke. More and more evidence suggests that a spectrum of epigenetic processes play an important role in the pathophysiology of cerebral ischemia. In the present review, we first discuss recent developments in epigenetic mechanisms, especially their roles in the pathophysiology of cerebral ischemia. Specifically, we focus on DNA methylation, histone deacetylase, histone methylation, and microRNAs (miRNAs) in the regulation of vascular and neuronal regeneration after cerebral ischemia. Additionally, we highlight epigenetic strategies for ischemic stroke treatments, including the inhibition of histone deacetylase enzyme and DNA methyltransferase activities, and miRNAs. These therapeutic strategies are far from clinic use, but preliminary data indicate that neuroprotective agents targeting these pathways can modulate neural cell regeneration and promote brain repair and functional recovery after cerebral ischemia. A better understanding of how epigenetics influences the process and progress of cerebral ischemia will pave the way for discovering more sensitive and specific biomarkers and new targets and therapeutics for ischemic stroke.