Investigation on the differentially expressed circular RNAs in myocardium of mice with diabetic cardiomyopathy / 中华心血管病杂志

Objective: To identify the differentially expressed circular RNA (circRNA) in the myocardium of diabetic cardiomyopathy (DCM) mice, and analyze their possible biological functions and related regulatory network. Methods: C57BL/6 mice, aged 8 weeks, and weighing were 21-27 g. Eight mice were selected as the control group and 15 mice were selected as the experimental group. The diabetic mice model was established by intraperitoneal injection of streptozotocin in the experimental group. One week after injection, the fasting blood glucose level of mice was measured, and 12 diabetic mice were included in the final experimental group. All mice were fed for 12 weeks under the same laboratory conditions. The cardiac structure and function were detected by echocardiography. Diabetic mice with the left ventricular ejection fraction less than 60% and the E/A less than 1.6 were selected as DCM group (n=3). Mice in DCM group and control group were then sacrificed under deep anesthesia. RNA was extracted from myocardial tissue. High-throughput RNA sequencing technology was used to sequence and identify the RNA in the myocardial tissue of DCM group and normal control group, and the difference was analyzed by DeSeq2. The analysis results were verified at the tissue level by RT-qPCR, and the differential circRNA were analyzed by GO and KEGG pathway analysis. The differentially expressed circRNA-microRNA(miRNA) interaction was predicted by the miRNA target gene prediction software. Results: A total of 63 differentially expressed circRNAs were found in the myocardium of DCM mice. The results of RT-qPCR showed that the tissue level expression of 8 differentially expressed circRNAs was consistent with the sequencing results, of which 7 were up-regulated and 1 was down-regulated. KEGG pathway analysis showed that the up-regulated circRNAs was mainly related to AMPK signal pathway and intercellular adhesion junction pathway, and the down-regulated circRNA was mainly related to cardiomyopathy. Go analysis showed that the up-regulated circRNA was mainly related to the binding process of ions, proteins, kinases and other factors in terms of molecular function, and was involved in regulating the intracellular structure, especially the composition of organelles in terms of cell components. The functional analysis of molecular function and cell components showed that the up-regulated circRNA were related to the cell component origin, recruitment and tissue, and thus participated in the regulation of cell biological process. The down regulated circRNA was related to catalytic activity in terms of molecular function, protein kinase binding process, transferase and calmodulin activity, and was closely related to the components of contractile fibers and the composition of myofibrils. These differentially expressed circRNAs were also related to biological processes such as lysine peptide modification, sarcomere composition, myofibril assembly, morphological development of myocardial tissue, myocardial hypertrophy and so on. Conclusions: In this study, we detected the novel differentially expressed circRNAs in the myocardium of DCM mice, and bioinformatics analysis confirmed that these circRNAs are related to oxidative stress, fibrosis and death of cardiomyocytes, and finally participate in the pathophysiological process of DCM.

Analysis on the expression profile of circRNAs in hypertrophic myocardium mice / 中华心血管病杂志

Objective: To explore the differential expression of circRNAs and their potential impact on the pathophysiological process in cardiac hypertrophy. Methods: Six SPF C57BL/6J male mice, aged 8 to 10 weeks, were randomly divided into transverse aortic constriction (TAC) group (n=3) or sham operation(sham) group (n=3) according to random number table method. TAC mouse model was used to induce cardiac hypertrophy. Four weeks after surgery, high-throughput sequencing analysis was performed to detect differentially expressed circRNA in left myocardial tissues of mice between TAC group and sham group, and principal component analysis of circRNA was performed by R language software. Enrichment analysis was performed by GO and KEGG databases to predict the basic functions of differentially expressed circRNA-derived genes and their biological pathways. The differentially expressed circRNAs in the sequencing results were verified by real-time fluorescence quantitative polymerase chain reaction. Cytoscape software was used to construct circRNA-microRNA (miRNA) network maps to predict their interactions by combining differentially expressed circRNA and TargetScan predicted miRNA sites. Results: Principal component analysis was performed on 4 580 circRNAs detected from 6 samples of mice in TAC group and sham group. The results of R language software indicated that the variance contribution rate of the first 3 principal components, namely the first, second and third principal components, was 91.01%, 3.19% and 2.01%, respectively, and the cumulative variance contribution rate of the 3 components was 96.21%. Among the differentially expressed circRNAs, 6 (19%) were up-regulated and 25 (81%) were down-regulated in the TAC group. GO analysis showed that differentially expressed circRNA was closely related to the occurrence and development of cardiac hypertrophy, and KEGG pathway analysis suggested that downregulated circRNA expression was involved in the regulation of actin cytoskeleton. Fifteen out of the 31 differentially expressed circRNAs were selected for real-time fluorescence quantitative polymerase chain reaction verification, and the results showed that 8 circRNAs were consistent with sequencing results. circRNA-miRNA co-expression network analysis results showed that chr11:65218529-65233184-interacts with mmu-miRNA-30e-3p and mmu-miRNA-30a-3p. Conclusions The differential expression of circRNA in hypertrophic myocardium mice is evidenced in TAC mouse model. circRNA may interact with the corresponding miRNA to influence the occurrence and development of cardiac hypertrophy through autophagy-related cellular hypertrophy pathway or apoptosis-related pathological phenotypes.

Imaging Features of Abnormal Neural Connectivity in Autistic Children / 中国康复理论与实践

Objective:To analyze the structure and function of white matter in autistic children by using diffusion tensor imaging (DTI) and magnetic resonance spectroscopy (MRS), to explore the imaging features of abnormal neural connectivity in children with autism. Methods:Autism group (n = 14) and control group (n = 8), aged two to nine years, underwent DTI and MRS scan. Bilateral frontal lobe, hippocampus, genu and splenium of corpus callosum and cerebellum white matter were selected as regions of interest. The data of DTI and MRS were processed by Functool 2.6 software of GEAW4.2 workstation. The fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of DTI, the absolute concentrations of N-acetylaspartate (NAA), choline (Cho), creatinine (Cr) and the ratios of NAA/Cr and Cho/Cr were recorded respectively. Results:Compared with the control group, the FA of left hippocampus (F = 5.922, P = 0.033) and the absolute concentration of Cr in left and right hippocampus (F > 4.715, P < 0.05) decreased significantly in the autism group. The FA was lower in left corpus callosum genu than in the right one (F = -2.335, P = 0.042), and the ADC was higher in left corpus callosum splenium than in the right one (F = 3.520, P < 0.01) in the autism group. The absolute concentration of NAA, Cho and Cr in left frontal lobe (|t| > 2.648, P < 0.05), the absolute concentration of NAA in left corpus callosum splenium (t = -3.076, P = 0.009) and Cho/Cr in left cerebellum (t = -2.225, P = 0.044) were significantly lower than those in the right cerebral hemisphere in the autism group. The DTI and MRS indexes were not different between left and right hemispheres in the control group (P > 0.05). Conclusion:Abnormal metabolite or functional alternations were found in the frontal lobe, hippocampus, cerebellum and the genu and splenium of the corpus callosum in autistic children, suggesting underconnectivity intra- or inter-hemispheric neural, especially in left hemisphere.