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.

Study on network pharmacological mechanism of "treating different diseases with same method" of Notoginseng Radix et Rhizoma in treating diabetic nephropathy, diabetic encephalopathy and diabetic cardiomyopathy / 中国中药杂志

Pharmacology network was used to investigate the common key target and signaling pathway of Notoginseng Radix et Rhizoma in the protection against diabetic nephropathy(DN), diabetic encephalopathy(DE) and diabetic cardiomyopathy(DCM). The chemical components of Notoginseng Radix et Rhizoma were obtained through TCMSP database and literature mining, and SwissTargetPrediction database was used to predict potential targets of Notoginseng Radix et Rhizoma. The disease targets of DN, DE and DCM were obtained through OMIM and GeneCards databases. The overlapped targets of component targets and disease targets of DN, DE and DCM were obtained, and the network of "chemical component-target-disease" was established. The enriched GO and KEGG of the overlapped genes were investigated by using ClueGo plug-in with Cytoscape. At the same time, the PPI network was constructed through STRING database, and the common key targets for the treatment of three diseases by Notoginseng Radix et Rhizoma were obtained through topological parametric mathematical analysis by Cytoscape. A total of 166 chemical components and 835 component targets were screened out from Notoginseng Radix et Rhizoma. Briefly, 216, 194 and 230 disease targets of DN, DE and DCM were collected, respectively. And 54, 45 and 57 overlapped targets were identified when overlapping these disease targets with component targets of Notoginseng Radix et Rhizoma, respectively. Enrichment analysis indicated that the AGE-RAGE signaling pathway and FoxO signaling pathway were the common pathways in the protection of Notoginseng Radix et Rhizoma against DN, DE and DCM. Network analysis of the overlapped targets showed that TNF, STAT3, IL6, VEGFA, MAPK8, CASP3 and SIRT1 were identified as key targets of Notoginseng Radix et Rhizoma against DN, DE and DCM, the selected key targets were verified by literature review, and it was found that TNF, IL6, VEGFA, CASP3 and SIRT1 had been reported in the literature. In addition, there were the most compounds corresponding to the commom core target STAT3, indicating that more compounds in Notoginseng Radix et Rhizoma could regulate STAT3. This study indicated that Notoginseng Radix et Rhizoma potentially protected against DN, DE and DCM through regulating AGE-RAGE signaling pathway and FoxO signaling pathway and 7 common targets including TNF, STAT3, IL6, VEGFA, MAPK8, CASP3 and SIRT1. This study provided a reference for the research of "different diseases with same treatment" and also elucidated the potential mechanism of Notoginseng Radix et Rhizoma against DN, DE and DCM.

Combination of Dendrobium Mixture and Metformin Curbs the Development and Progression of Diabetic Cardiomyopathy by Targeting the lncRNA NEAT1

OBJECTIVES: This study aimed to explore the efficacy of combination treatment with dendrobium mixture and metformin (Met) in diabetic cardiomyopathy (DCM) and its effects on NEAT1 and the Nrf2 signaling pathway. METHODS: H9c2 cells were maintained in medium supplemented with either low (5.5 mmol/L) or high (50 mmol/L) glucose. Male Sprague-Dawley rats were fed a high-glucose diet and administered a single, low dose of streptozotocin (35 mg/kg) via intraperitoneal injection to induce the development of DM. After induction of DM, the rats were treated with dendrobium mixture (10 g/kg) and Met (0.18 g/kg) daily for 4 weeks. Next, quantitative reverse transcription (qRT)-PCR and western blotting were performed to evaluate the expression levels of target genes and proteins. Flow cytometry was performed to assess apoptosis, and hematoxylin and eosin staining was performed to evaluate the morphological changes in rat cardiac tissue. RESULTS: In patients with diabetes mellitus (DM) and myocardial cells and heart tissues from rats with high glucose-induced DM, NEAT1 was downregulated, and the expression levels of Nrf2 were decreased (p<0.01, p<0.001). The combination of dendrobium mixture and Met upregulated the expression of NEAT1 which upregulated Nrf2 by targeting miR-23a-3p, resulting in reduced apoptosis and improved cardiac tissue morphology (p<0.01, p<0.001). CONCLUSION: Dendrobium mixture and Met upregulated the expression of NEAT1 in DCM, thereby inhibiting apoptosis of myocardial cells.

El aumento de la expresión del ARNm de la enzima convertidora de angiotensina I homóloga (ECA-2) inducido por atorvastatina se asocia a menor fibrosis e hipertrofia ventricular izquierda en un modelo de cardiomiopatía diabética / Atorvastatin induced increase in homologous angiotensin i converting enzyme (ACE2) mRNA is associated to decreased fibrosis and decreased left ventricular hypertrophy in a rat model of diabetic cardiomyopathy

Objetivos. Evaluar el efecto de atorvastatina sobre la progresión del remodelado cardiaco y la expresión de ECA-2 en el miocardio de ratas diabéticas. Materiales y métodos. La diabetes fue inducida en ratas Holtzman con una inyección intraperitoneal de estreptozotocina. Los animales fueron divididos en tres grupos: (1) ratas control, (2) ratas diabéticas y (3) ratas diabéticas tratadas con atorvastatina (50 mg/kg/día). Después de ocho semanas de tratamiento, los corazones fueron extraídos para el análisis morfométrico, la cuantificación de colágeno y la determinación de los niveles de ARNm de ECA y ECA-2. Resultados. El índice de hipertrofia ventricular y el depósito de colágeno se incrementaron significativamente en las ratas diabéticas. La administración de atorvastatina previno estos cambios sin modificar los niveles de colesterol. La hiperglicemia produjo un incremento significativo en los niveles del ARNm de ECA y una marcada disminución en la expresión de ECA-2 en el miocardio de ratas diabéticas. La administración de atorvastatina indujo la expresión del ARNm de ECA-2 e inhibió la sobreexpresión del ARNm de ECA en el miocardio de las ratas diabéticas. Conclusiones. Nuestros resultados indican que la atorvastatina, independientemente de su capacidad para disminuir el colesterol, normaliza la relación de la expresión de ECA/ECA-2 y atenúa el desarrollo del remodelado adverso en el corazón diabético.

Objectives. This study has investigated the effect of atorvastatin on the progression of cardiac remodelling and ACE- 2 expression in diabetic myocardium in rats. Materials and Methods. Diabetes was induced in Holtzman rats with an intraperitoneal injection of streptozotocin. The animals were divided into 3 groups: (1) normal control rats, (2) diabetic rats and (3) diabetic rats treated orally with atorvastatin (50 mg/kg/day). After eight weeks of treatment, the hearts were removed for morphometric studies, collagen content assay and genetic expressions of ACE and ACE2 mRNA. Results. Myocardial hypertrophy index and collagen deposition were increased in diabetic rats, but not in the treated-diabetic rats, without producing changes in cholesterol levels. Myocardial ACE mRNA levels were increased while ACE2 mRNA levels were decreased in diabetic rats. Atorvastatin administration attenuated overexpression of ACE mRNA and overexpression of ACE-2 mRNA in diabetic rats. Conclusions. Our results indicate that atorvastatin, independently of its cholesterol-lowering capacity, lowers the ACE/ACE2 ratio to normal values and attenuates the development of adverse remodeling in the diabetic heart.