Cardiac hypertrophy induced by exercise training:the function of AT1 receptor,autophagy and miRNAs

As a mechanical and exogenous stimulus, exercise training induces cardiac physiological hypertrophy, and the cardiac structure is changed slowly, steadily and coordinately. Simultaneously, energy metabolism and function of the cardiac muscle are also improved. These are positive adaptations in the heart when experiencing endurance exercise training. Recently, angiotensin Ⅱ type 1 (AT1) receptor, autophagy and miRNAs are all considered as important regulators to cardiac hypertrophy induced by exercise training at different molecular levels. Fully understanding the relations and the important role of AT1 receptor, autophagy and miRNAs in cardiac physiological hypertrophy will further enrich the signaling pathway of cardiac hypertrophy induced by exercise training.     

Roles of microRNAs in glioma

MicroRNAs (miRNAs) are critical regulators of gene expression. These small, non-coding RNAs are believed to regulate more than one third of protein-coding genes, and have been implicated in the control of many biological processes, including the biology of glioma. The functional significance in some of the miRNAs begins to emerge. This paper reviews the biogenesis of miRNAs, their roles in neuronal development and tumorigenesis of gliomas, and their contribution as tumor biomarkers. Research in this area is quickly gathering pace and is illuminating important aspects of the diseases that may ultimately lead to novel therapeutic interventions, as well as diagnostic and prognostic tools for brain tumors.     

Progress on epigenetic regulation of long noncoding RNAs in cardiac development and heart diseases

It was previously revealed that noncoding RNAs, especially microRNAs, control cardiac genes and regulate heart function. Recently, growing evidence from high-throughput genomic platforms has confirmed that long noncoding RNAs (lncRNAs) serve as new and enigmatic regulators in cardiac development and homeostasis. Nevertheless, little is known about their characteristics compared to microRNAs. Here, we review the latest progress on lncRNAs in cardiac biology and diseases, summarizing detailed knowledge of their functions and novel cardiac-related gene regulatory mechanisms in epigenetic processes. Finally, we highlight that lncRNAs could be promising therapeutic targets and diagnostic biomarkers in cardiac pathophysiology.     

ceRNA mechanism of circRNA-miRNA-mRNA in atherosclerosis

Atherosclerosis (AS) is a common cardiovascular disease and a major cause of coronary heart di-sease, cerebral infarction and peripheral vascular disease. Circular RNA (circRNA) is a class of circularly closed non-co-ding RNAs that play an important role in the formation of AS. Physiological and pathological significances of the processes such as lipid metabolism, endothelial cell damage, vascular smooth muscle cell proliferation and migration, monocyte pha-gocytosis and foam-like cell formation, and inflammatory responses are involved in the development of AS. Most circRNA adjust mRNA expression by regulating microRNAs (miRNAs). circRNA provides new ideas and targets for the diagnosis and treatment of AS.     

Recent advances in Wnt-frizzled cascade and its relation to cardiovascular diseases

Many researches have focused on the Wnt-frizzled cascade in the recent years, while much work has been done in neoplastic diseases and embryology, the role of the Wnt-frizzled signal transduction pathway in cardiovascular diseases has only recently begun to be explored. It plays a very important role in many physiological and pathophysiological processes, such as its transduction pathway, the healing after myocardial infarction, the proliferation, differentiation and orientation of cardiomyocytes, angiogenesis/neovascularization, cardiac hypertrophy and heart failure, the deposition of the extracellular matrix and so on. This article is aimed at its relation with myocardial infarction and the role of this pathway in cardiovascular diseases.     

Regulatory effect of miRNA enfolded in microparticles on endothelial cells

Endothelial cells are the cells lining the inner surfaces of blood vessels. They build up a single cell layer and play an important role in the regulation of vascular functions and the maintenance of homeostasis. The activation or injury of endothelial cells is associated with multiple diseases, including hypertension, atherosclerosis, cancer, diabetes, etc. Recent studies have found that microparticles are involved in the process of endothelial cell injury, thus playing a part in the development of many diseases. miRNAs enfolded in the microparticles have become importance in recent years. Moreover, recent studies also found that the concentration of the miRNAs enfolded in the microvesicles is higher than that of the miRNAs in the plasma, which means that the microparticles are the main form of miRNAs present in peripheral circulatory system. This article is to review the recent research progress in microparticle-encapsulated miRNAs and their regulatory effect on endothelial cell injury.     

Temporal and spatioal effects of enriched miRNAs in brain and possible role in neural tube defects

MicroRNAs (miRNAs) are known to play an important role in regulating the cell proliferation, differentiation and organogenesis. Abnormal expression of miRNAs is associated with increased risk for various diseases, such as neural tube defects (NTD), which is a severe developmental disease as the result of closing the neural tube incompletely or too early. The present review summarizes some enriched miRNAs in the brain of mammals and their spatial temporal feature, and tries to elaborate the relationship between the aberrant expression of miRNAs and the pathogenesis of NTD.     

Influence of energetic metabolism alteration on cardiac myocyte apoptosis

Many studies indicate that apoptosis is involved in the progression of congestive heart failure. At present, mechanisms that mitochondria regulates cell apoptosis is widely accepted.Cardiac myocytes have abundant mitochondria, which plays an important role in maintenance of cell physiological function. Recent studies find that cardiac energy metabolic shifts occur as a normal response to diverse physiologic and dietary conditions and as a component of the pathophysiologic processes which accompany cardiac hypertrophy, heart failure, and myocardial ischemia.Both clinical and experimental studies show that cardiac function can be improved and apoptosis is inhibited by intervention in energetic metabolism of myocytes.     

枣树阶段转变相关microRNA家族的鉴定及其表达分析

与其他果树相比,枣树具有童期短、成花快的特征.已有研究表明,多个microRNA(miRNA)家族参与植物阶段转变和开花时间调控等过程.研究枣树阶段转变相关的miRNA家族对果树童期调控具有重要意义.以枣实生后代植株不同发育阶段(节位)的当年生枝(枣吊)为材料,通过Small RNA测序,在童期、过渡期和成年期等3个时...     

Differentially expressed microRNAs during solid endosperm development in coconut (Cocos nucifera L.)

MicroRNAs (miRNAs) are a class of 20–24 nt, endogenously expressed, non-coding RNAs that play important regulatory roles in plants and animals. To identify miRNAs potentially involved in tissue development and compound anabolism, we studied miRNA expression profiles in endosperm of coconut at different developmental stages. Based on the annotation in miRBase (release 10.1), we measured a total of 179 miRNAs in immature (95 expressed miRNAs) and mature tissues (176 expressed miRNAs) using microarrays, respectively. The comparative analyses on miRNA expression profiles between these two groups of tissues showed that 23 miRNAs were up-regulated and nine miRNAs were down-regulated in matured endosperm. We further confirmed the increased expression of four miRNAs and decreased expression of a miRNA in immature endosperm using real-time PCR. Moreover, we computationally predicted the target genes of 32 miRNAs with differential expression (p < 0.01), and identified the lowest-score targets of six miRNAs. Finally, we discussed the potential functional relevance of several differentially expressed miRNAs.     

Functional analysis of differential microRNA expression profile in mouse fibrotic liver tissues induced by CCl4

AIM:To discover the expression profile of microRNAs (miRNAs) in mouse fibrotic liver tissues induced by carbon tetrachloride (CCl4), and to investigate the functions of these differential miRNAs based on the gene ontology (GO) analysis and KEGG Pathway analysis. METHODS:The mice were randomly divided into normal group and model group. Liver fibrosis was induced by subcutaneous injection of CCl4. miRNA expression profile of the liver tissues was assayed by a mouse miRNA microarray (Agilent 12.0). The differential expression of miRNAs between the normal and model mice was screened, and GO analysis and KEGG Pathway analysis were performed to determine the functions of these differential miRNAs. RESULTS:Thirty-nine miRNAs with differential expression were discovered in the model mice compared with the normal mice, among which 23 were up-regulated and 16 were down-regulated. GO analysis and KEGG Pathway analysis indicated that most pathological processes of liver fibrosis regulated by miRNAs included cell proliferation and activation, cell apoptosis, cell cycle, cell adhesion, inflammatory reaction, cell migration, transforming growth factor β (TGF-β) signaling pathway, Wnt signaling pathway and proteometabolism process. GO analysis revealed that the key up-regulated miRNAs were mmu-miR-322, mmu-miR-15b, mmu-miR-195, mmu-miR-200b and mmu-miR-214, and the key down-regulated miRNAs were mmu-miR-16, mmu-miR-130a, mmu-miR-101b, mmu-miR-30a and mmu-miR-30e. Analyzing the target genes screened out by GO analysis and Pathway analysis simultaneously, we found that the key up-regulated miRNAs included mmu-miR-200b, mmu-miR-322, mmu-miR-106b, mmu-miR-23a and mmu-miR-15b, and the key down-regulated miRNAs included mmu-miR-16, mmu-miR-30e, mmu-miR-30c, mmu-miR-30a and mmu-miR-130a. CONCLUSION: Differential expression of miRNAs is discovered in mouse fibrotic liver tissues induced by CCl4 compared with the normal liver tissues. Most of the pathological processes involved in liver fibrosis may be regulated by miRNA, such as cell proliferation and activation, cell adhesion and apoptosis, cell migration and differentiation, metabolism, TGF-β receptor signaling pathway and so on.     

Protocol: a highly sensitive RT-PCR method for detection and quantification of microRNAs

MicroRNAs (miRNAs) are a class of small non-coding RNAs with a critical role in development and environmental responses. Efficient and reliable detection of miRNAs is an essential step towards understanding their roles in specific cells and tissues. However, gel-based assays currently used to detect miRNAs are very limited in terms of throughput, sensitivity and specificity. Here we provide protocols for detection and quantification of miRNAs by RT-PCR. We describe an end-point and real-time looped RT-PCR procedure and demonstrate detection of miRNAs from as little as 20 pg of plant tissue total RNA and from total RNA isolated from as little as 0.1 μl of phloem sap. In addition, we have developed an alternative real-time PCR assay that can further improve specificity when detecting low abundant miRNAs. Using this assay, we have demonstrated that miRNAs are differentially expressed in the phloem sap and the surrounding vascular tissue. This method enables fast, sensitive and specific miRNA expression profiling and is suitable for facilitation of high-throughput detection and quantification of miRNA expression.     

Research progress of magnesium ion and coronary heart disease

Magnesium ion (Mg2+) is the most abundant divalent cation in the human cells, which plays an important role in cellular activities. In the cardiovascular system, Mg2+ is one of the most important cationic ions studied following calcium and potassium. Mg2+-related diseases include atherosclerosis, hypertension, cardiac hypertrophy, and so on. Here we review the relationship between Mg2+ and the coronary atherosclerotic heart disease.     

Progress in protein families of gap junction

Gap junctions are intercellular channels, which connect adjacent cells and allow direct molecular exchange of low molecular weight between them. Three protein families including connexins, innexins and ponnexins are involved in gap junctions. Connexins are only found in chordate and innexins compose the gap junctions of invertebrates, while pannexins are ubiquitous and present in both vertebrates and invertebrates. Gap junctions in metazoan play important roles in electrical coupling, regulating proliferation, differentiation, and embryonic development. Evidently, the defects of gap junctions resulting form proteins contribute to many diseases of vertebrates and invertebrates, such as tumor, heart diseases, nervous system disorders and other diseases in human.     

Function and significance of integrin-linked kinase in heart

Integrin-linked kinase (ILK) is a widely expressed protein kinase that relate to cellular growth and differentiation. It is most abundant in the heart. Recently, many researches revealed that ILK is highly relevant to cardiac response to biomechanical stresses. Also, ILK plays important roles in regulation of the occurrence and development of cardiac hypertrophy, dilated cardiomyopathy, viral myocarditis and myocardial senescence via correlation to several classical signal transduction pathway. Meanwhile, ILK functions in protection after myocardial infarction. This article will try to summarize the effects and relevant mechanism of ILK in above-mentioned aspects, overall reveals the roles of ILK in heart and its potential clinical significance.     

Strategies for preventing and curing insulin resistance in lipid-overloaded cardiac myocytes

Insulin resistance is a central pathological mechanism of type 2 diabetes mellitus. Diabetic cardiomyopathy and heart failure are frequent co-morbid conditions in type 2 diabetic patients. Long-chain fatty acids (LCFAs) are the major energy source for the heart to sustain contractile activity, and the diabetic heart becomes almost entirely dependent on LCFAs for energy production. Elevated intracellular levels and prolonged accumulation of LCFA metabolites worsen the state of insulin resistance, and further induce diabetic cardiomyopathy and heart failure. It is indicated that sarcolemmal fatty acid uptake and mitochondrial β-oxidation are the rate-limiting steps in cardiac LCFA flux and utilization. Therefore, the inhibitions of carnitine palmitoyltransferase (CPT-I), β-oxidation enzymes and CD36/plasma membrane fatty acid-binding protein (FABPpm) translocation are the preferable strategies of limiting LCFA entry and LCFA metabolite accumulation, thus regressing cardiac insulin resistance, and eventually preventing diabetic heart failure.