Function of Cortactin/N-cadherin signal axis in pathological myocardial hypertrophy / 中国药理学通报

Aim To investigate the regulatory effect of Cortaetin on pathological myocardial hypertrophy induced by isoprenaline (ISO) and the underlying mechanism. Methods ISO was used to stimulate neonatal rat cardiomyocytes for 24 h, and myocardial hypertrophy model was established at the cellular level. C57BL/6 mice were injected subcutaneously with ISO for one week to establish myocardial hypertrophy model at animal level. RT-qPCR was used to detect the changes of mRNA and Western blot was used to detect the changes of relative protein content. Immunofluorescence was used to measure the subcellular location of Cortaetin and the change of its expression. The overex-pression of Cortaetin by adenovirus infection and the knockdown of Cortaetin by transfection of small interfering RNA were studied. Results On the cellular and animal levels, ISO-induced myocardial hypertrophy models were successfully established, and it was observed that ISO caused the decrease of Cortaetin and N-cadherin protein levels. Overexpression of Cortaetin could reverse the decrease of N-cadherin protein level and myocardial hypertrophy caused by ISO. Knockdown of Cortaetin showed the opposite effect. Conclusion Cortaetin, in combination with N-cadherin, may play a role in combating myocardial hypertrophy by enhancing the connections between cardiomyocytes.

Factor de crecimiento análogo a insulina-1 y cardiotrofina-1 inducido por ejercicio y su relación con hipertrofia miocárdica en maratonistas

Antecedentes: El ejercicio de alta intensidad induce hipertrofia miocárdica necesaria para adaptar al corazón a la mayor demanda de trabajo. Se desconoce si correr una maratón induce de forma aguda factores humorales asociados al desarrollo de hipertrofia miocárdica en atletas. Objetivo: Evaluar cardiotrofina-1 (CT1) y el factor de crecimiento análogo a insulina-1 (IGF-1), conocidos inductores de hipertrofia, en maratonistas previo y justo después de correr una maratón y su relación con hipertrofia cardíaca. Métodos: Estudio prospectivo ciego simple de atletas hombres que corrieron la maratón de Santiago. Se incluyó un grupo control sedentario. En todos los sujetos se realizó un ecocardiograma transtorácico estándar. Los niveles de CT1 e IGF-1 se determinaron en plasma obtenidos antes (basal) y justo después de haber terminado (antes de 15 minutos) la maratón, usando test de ELISA. Resultados: Los atletas tenían frecuencias cardíacas menores que los controles, asociado con una mayor hipertrofia miocárdica, determinado por el grosor del septo y pared posterior del corazón, y volúmenes del ventrículo y aurícula izquierda. Los niveles basales de CT1 e IGF-1 fueron similares entre atletas y controles sedentarios. El correr la maratón aumentó los niveles de estas dos hormonas en un subgrupo de atletas. Solo los atletas que incrementaron los niveles de IGF-1, pero no de CT1, tenían volúmenes de ventrículo izquierdo y derecho más grandes que los otros atletas. Conclusiones: IGF-1 que se incrementa de forma aguda por el ejercicio, pero no CT1, estaría asociado con el aumento de los volúmenes ventriculares observado en los atletas.

Background: High intensity exercise induces the development of myocardial hypertrophy necessary to adapt the heart to the increased work demand. Whether running a marathon is associated with acutely induced humoral factors responsible for the development of myocardial hypertrophy observed in athletes is not known. Objective: To evaluate the levels of cardiotrophin-1 (CT1) and insulin-like growth factor-1 (IGF-1), known hypertrophy inducers, in marathon runners before and just after running a marathon and their relationship with cardiac hypertrophy. Methodology: Single-blind prospective study of male athletes who ran the Santiago's marathon. A sedentary control group was included. All subjects underwent a standard transthoracic echocardiogram. CT1 and IGF-1 levels were determined in plasma obtained before (basal) and just after finishing (within 15 min) the marathon using ELISA assays. Results: Athletes had lower heart rates than controls, associated with greater myocardial hypertrophy, as determined by thickness of the heart's septum and posterior wall, and left atrial and ventricular volumes. Basal CT1 and IGF-1 levels were similar between athletes and sedentary controls. Marathon running increased the levels of these two hormones in a subgroup of athletes. Only the athletes who increased IGF-1 levels, but not CT1, had larger left and right ventricular volumes. Conclusion: IGF-1 acutely increased by exercise, but not CT1, was associated with the augmented ventricular volumes observed in athletes.

Effect of histone methylase EZH2 on proliferation and apoptosis of hypertrophic myocardial cells of AC16 / 国际生物医学工程杂志

Objective:To explore the molecular mechanism of the effect of the histone methylase zeste gene enhancer homolog 2 (EZH2) on the proliferation and apoptosis of human hypertrophic cardiomyocytes AC16.Methods:The AC16 hypertrophic cardiomyocyte model was constructed by adding angiotensin Ⅱ to the AC16 cell culture medium. The cells were divided into four groups, including the blank control group, the angiotensin Ⅱ group, the empty vector + angiotensin Ⅱ group, and the EZH2 overexpression + angiotensin Ⅱ group. The expression levels of EZH2 and brain natriuretic peptide ( BNP) genes were measured using fluorescent quantitative PCR. The EZH2, trimethylation of lysine at position 27 of histone H3 (H3K27me3), and BNP proteins expression were detected by Western Blot. The MTS method was used to detect the proliferation of AC16 cell. The Annexin V-FITC/PI double staining method was used to detect the apoptosis of AC16 cell. Results:Compared with the blank control group, the expression levels of EZH2 and H3K27me3 in the angiotensin Ⅱ group were decreased, the expression level of BNP was increased, cell proliferation was decreased, and apoptosis was increased (all P < 0.001). Compared with the empty vector + angiotensin Ⅱ group, the expression levels of EZH2 and H3K27me3 in the EZH2 overexpression + angiotensin Ⅱ group were increased, the expression level of BNP was decreased, the cell proliferation level was increased, and the apoptosis level was decreased (all P < 0.001). There was no significant difference between the angiotensin Ⅱ group and the empty vector + angiotensin Ⅱ group (all P > 0.05). Conclusions:Histone methylase EZH2 has an effect on the proliferation and apoptosis of AC16 cell, providing a reference for the treatment of myocardial hypertrophy and revealing the exact pathogenesis of myocardial hypertrophy.

Analysis on mechanism of frankincense volatile oil in prevention and treatment of cardiac hypertrophy based on in vitro cell experiment and network pharmacology / 中国临床药理学与治疗学

To explore the potential mechanism of frankincense volatile oil in the prevention and treatment of cardiac hypertrophy based on in vitro cell experiment and network pharmacology. METHODS: The anti-hypertrophic effect of frankincense volatile oil was investigated by isoproterenol induced H9c2 cardiomyocytes hypertrophy model. The active chemical components and targets of frankincense volatile oil and targets associated with cardiac hypertrophy were obtained by CNKI, Pubmed, Pubchem databases, etc. String database and Cytoscape 3.8.0 software were used to construct protein-protein interaction network (PPI) and a network of "drug-active component-key target-disease" of frankincense volatile oil in order to screen the key targets of frankincense volatile oil against cardiac hypertrophy. The fluorescent quantitative PCR experiments were performed to verify those key targets. Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotation analysis of key target genes were performed using David online analysis tool. RESULTS: In vitro cell experiments showed that frankincense volatile oil significantly inhibited the isoproterenol induced increases in cardiomyocytes surface area and protein synthesis, and upregulations of ANP and β-MHC mRNA. A total of 87 active components and 36 ingredient-disease targets of frankincense volatile oil were screened. Network analysis showed that ESR1, NOS3, PTGS2, TNF, MAPK14, and PPARG were key targets. Fluorescence quantitative PCR experiments results indicated that frankincense volatile oil inhibited isoproterenol induced upregulations of ESR1, PTGS2, TNF, and MAPK14 mRNA levels, and downregulations of NOS3, PPARG mRNA levels, respectively. In addition, the GO functional enrichment analysis showed that its biological pathways mainly included lipopolysaccharide-mediated signaling pathway, positive regulation of nitric oxide biosynthetic process, caveola, enzyme binding, etc. The KEGG pathway enrichment analysis included 22 KEGG pathways, which were closely related to VEGF signaling pathway, TNF signaling pathway, sphingolipid signaling pathway and others. CONCLUSION: The active components of frankincense volatile oil may regulate VEGF signaling pathway, TNF signaling pathway, Sphingolipid signaling pathway by acting on ESR1, NOS3, PTGS2, TNF, MAPK14 and PPARG targets, thereby affecting the regulation of lipopolysaccharide-mediated signaling pathway, positive regulation of nitric oxide biosynthetic process, caveola, and enzyme binding, and improving cardiac hypertrophy.

Inhibition of activated K-opioid receptor to myocardical hypertrophy induced by ET-1 in neonatal rats by extracellular signal-regulated kinase pathway / 中国药理学通报

Aim To investigate the inhibitory effect of kappa-opioid receptor(κ-OR)stimulation on extracellular signal-regulated kinase pathway on ET-1-induced cardiomyocyte hypertrophy in vitro cultured myocardial cells from neonatal rats.Methods Myocardial cells of neonatal rats were cultured in vitro.The hypertrophic myocytes were induced by ET-1(10 nmol·L-1)before κ-OR agonist U50488H(1 μmol·L-1)was administered.The antihypertrophic effect of κ-OR stimulation was observed in the presence of U0126(1μmol·L-1), Ro-31-8220(50 nmol·L-1)and PTX(5 mg·L-1).The cardiomyocytes volume was measured by computer photographalysis system.The relative expression of ERK1/2 was determined by Western blot.The morphological changes in cardiomyocytes were observed under an inverted phase contrast microscope.The expression of mRNA of atrial natriuretic peptide(ANP)was determined by RT-PCR.Results Compared with normal control group, ET-1 could induced cardiomyocyte hypertrophy.Compared with ET-1 model group, U50488H(1 μmol·L-1)could obviously inhibit ET-1-induced increase of the cardiomyocytes volume, expression of ANPmRNA and expression of ERK1/2, which was similar to U0126(1 μmol·L-1)and Ro-31-8220(50 nmol·L-1); however, the inhibitory effects of U50488H were partly lost when preincubated with U0126(1 μmol·L-1)and Ro-31-8220(50 nmol·L-1); the inhibitory effects of U50488H, U0126(1 μmol·L-1)and Ro-31-8220(50 nmol·L-1)were lost when preincubated with NOR-BNI.Conclusion The stimulation of kappa-opiod can inhibit myocardial hypertrophy induced by ET-1, which is possibly via attenuating ERK1/2.

Effect and mechanism of leonurine on pressure overload-induced cardiac hypertrophy in rats / 中国中药杂志

To investigate the effects of leonurine(Leo) on abdominal aortic constriction(AAC)-induced cardiac hypertrophy in rats and its mechanism. A rat model of pressure overload-induced cardiac hypertrophy was established by AAC method. After 27-d intervention with high-dose(30 mg·kg~(-1)) and low-dose(15 mg·kg~(-1)) Leo or positive control drug losartan(5 mg·kg~(-1)), the cardiac function was evaluated by hemodynamic method, followed by the recording of left ventricular systolic pressure(LVSP), left ventricular end-diastolic pressure(LVESP), as well as the maximum rate of increase and decrease in left ventricular pressure(±dp/dt_(max)). The degree of left ventricular hypertrophy was assessed based on heart weight index(HWI) and left ventricular mass index(LVWI). Myocardial tissue changes and the myocardial cell diameter(MD) were measured after hematoxylin-eosin(HE) staining. The contents of angiotensin Ⅱ(AngⅡ) and angiotensin Ⅱ type 1 receptor(AT1 R) in myocardial tissue were detected by ELISA. The level of Ca~(2+) in myocardial tissue was determined by colorimetry. The protein expression levels of phospholipase C(PLC), inositol triphosphate(IP3), AngⅡ, and AT1 R were assayed by Western blot. Real-time quantitative PCR(qRT-PCR) was employed to determine the mRNA expression levels of β-myosin heavy chain(β-MHC), atrial natriuretic factor(ANF), AngⅡ, and AT1 R. Compared with the model group, Leo decreased the LVSP, LVEDP, HWI, LVWI and MD values, but increased ±dp/dt_(max) of the left ventricle. Meanwhile, it improved the pathological morphology of myocardial tissue, reduced cardiac hypertrophy, edema, and inflammatory cell infiltration, decreased the protein expression levels of PLC, IP3, AngⅡ, AT1 R, as well as the mRNA expression levels of β-MHC, ANF, AngⅡ, AT1 R, c-fos, and c-Myc in myocardial tissue. Leo inhibited AAC-induced cardiac hypertrophy possibly by influencing the RAS system.

Advances in the anti-ageing effects of GDF11 in blood / 中国输血杂志

Growth differentiation factor 11 (GDF11), a member of the transforming growth factor β superfamily, is widely expressed in multiple species such as human, mouse, rat, horse and sheep. Moreover, GDF11 is implicated in diverse biological functions and plays an important role in regulating anterior/posterior patterning, skeletal muscle regeneration, bone formation, vascular remodeling and neurogenesis. Recent studies have revealed that GDF11 in blood reverses age-related cardiac hypertrophy, skeletal muscle dysfunction and age-related cognitive decline, suggesting the potential value of GDF11 on anti-ageing. However, some other studies questioned the effects of GDF11 on anti-ageing. Herein, we highlighted structural characteristics of GDF11, advances in effects of GDF11 on anti-ageing, and the controversies of GDF11, to provide new insights for future studies on anti-ageing.

Research progress of miroRNA in the mechanism of cardiac hypertrophy and its role as new drug targets / 国际生物医学工程杂志

Cardiac hypertrophy is a common physiological or pathological process, and pathological cardiac hypertrophy can lead to heart failure, sudden death, etc. The role of microRNA (miRNA or MIR) in myocardial hypertrophy has gradually attracted public attention. miR-1 plays a certain protective role in the occurrence of cardiac hypertrophy. miR-133 is a key factor in the establishment of mast gene program, which is very important for the development of myocardial hypertrophy. Carvedilol and other drugs can regulate the expression of miR-133. miR-208a plays an important physiological role in the cardiovascular system, and its expression level changes dynamically in a variety of cardiovascular diseases such as cardiac hypertrophy, which is closely related to the progression and prognosis of the disease. The expression of miR-199a is up-regulated in pressure-overload cardiac hypertrophy, and it is found that miR-199a can inhibit autophagy of cardiomyocytes and induce the occurrence of cardiac hypertrophy. miR-200c can protect cardiomyocytes through a variety of pathways. miRNA may become an important biomarker or drug therapeutic target for cardiac hypertrophy. With the deepening of the research on non-coding RNAs including miRNA, its regulation on the occurrence of cardiac hypertrophy and the pathological process of heart failure will be further revealed.

MicroRNA144￣3p targeting histone deacetylase 2 promoting cardiomyocyte hypertrophy and cardiac function damage / 解剖学报

Objective To investigate the role and possible mechanism of microRNA(miR)144-3p in promoting cardiomyocyte hypertrophy. Methods Forty-five C57BL/ 6 mice were divided into control group, myocardial hypertrophy model group (model group), and miR144-3p transfection group (transfection group) according to their transfection method. The cardiac function related indexes of three groups of mice were detected. HE staining was performed on mouse myocardial tissue.The expression of miR144-3p in mouse cardiomyocytes was detected by Real-time PCR. Antinuclear factor (ANF), β-myosin heavy chain (β-MHC), actin α1 (Acta1) and histone deacetylase 2 (HDAC2) were detected by Western blotting in three groups. Results Compared with the control group, the interventricular septal thickness- diastolic(IVSd), interventricular septal thickness-systolic(IVSs), diastolic left ventricular posterior wall thickness(IVPWd), systolic left ventricular posterior wall thickness(IVPWs), ejection fraction(EF), cardiac weight index and left cardiac index of the model group and the transfection group were significantly higher, while systolic left ventricular diameter (LVDs) and diastolic left ventricular diameter(LVDd)were lower (P0. 05). Compared with the control group, the relative expression of miR144-3p in the model group and the transfection group was significantly higher than that in the model group (P<0. 05). Compared with the control group, the expression levels of antinuclear factor, β-myosin heavy chain, Actinα1 and histone deacetylase 2 in the model group and the transfected group were significantly higher (P<0. 05). Conclusion miR144-3p can aggravate cardiac hypertrophy by up-regulating HDAC2 and is expected to become a new therapeutic target.

Screening and identification the hub genes of cardiac hypertrophy in mice / 解剖学报

Objective To screen and identify the hub genes closely related to cardiac hypertrophy by using bioinformaticsmethod and biological experiments. Methods The chip data related to cardiac hypertrophy in mice were downloaded from the Gene Expression Omnibus (GEO) database, and the GE02R online tool was adopted to screen for differentially expressed genes; DAVID 6.7, String 11.0 and Cytoscape 3.7. 0 softwares were used to analyze differentially expressed genes; Kunming mice were randomly divided into a normal saline group (n = 6) and an angiotensin II (Ang II) group (n = 6) to establish a cardiac hypertrophy model, the expression of hub gene in Kunming mouse model of cardiac hypertrophy induced by Ang II was detected by Real-time PCR method. Results A total of 202 common differentially expressed genes and 12 hub genes were selected; the Real-time PCR result demonstrated that decorin(Dcn), HADHA and heat shock protein (HSP) 90αA 1 were significantly down-regulated in the Angli group. Conclusion The selected hub genes can influence the development of cardiac hypertrophy in Kunming mice through extracellular matrix and transforming growth factor β(TGF-β).

Research on role of Nampt in regulating ERK1/2 in pathological myocardial hypertrophy / 中国药理学通报

Aim To investigate the role of Nampt in regulating ERK1/2 in cardiac hypertrophy and its mechanisms. Methods The primary neonatal rat cardiomyocytes were stimulated by phenylephrine (PE) (100 μmol · L

Testosterone activates glucose metabolism through AMPK and androgen signaling in cardiomyocyte hypertrophy

BACKGROUND: Testosterone regulates nutrient and energy balance to maintain protein synthesis and metabolism in cardiomyocytes, but supraphysiological concentrations induce cardiac hypertrophy. Previously, we determined that testosterone increased glucose uptake­via AMP-activated protein kinase (AMPK)­after acute treatment in cardiomyocytes. However, whether elevated glucose uptake is involved in long-term changes of glucose metabolism or is required during cardiomyocyte growth remained unknown. In this study, we hypothesized that glucose uptake and glycolysis increase in testosterone-treated cardiomyocytes through AMPK and androgen receptor (AR). METHODS: Cultured cardiomyocytes were stimulated with 100 nM testosterone for 24 h, and hypertrophy was verified by increased cell size and mRNA levels of ß-myosin heavy chain (ß-mhc). Glucose uptake was assessed by 2-NBDG. Glycolysis and glycolytic capacity were determined by measuring extracellular acidification rate (ECAR). RESULTS: Testosterone induced cardiomyocyte hypertrophy that was accompanied by increased glucose uptake, glycolysis enhancement and upregulated mRNA expression of hexokinase 2. In addition, testosterone increased AMPK phosphorylation (Thr172), while inhibition of both AMPK and AR blocked glycolysis and cardiomyocyte hypertrophy induced by testosterone. Moreover, testosterone supplementation in adult male rats by 5 weeks induced cardiac hypertrophy and upregulated ß-mhc, Hk2 and Pfk2 mRNA levels. CONCLUSION: These results indicate that testosterone stimulates glucose metabolism by activation of AMPK and AR signaling which are critical to induce cardiomyocyte hypertrophy.

Role of FAK signaling in chagasic cardiac hypertrophy

Abstract Cardiac hypertrophy and dysfunction are a significant complication of chronic Chagas disease, with heart failure, stroke, and sudden death related to disease progression. Thus, understanding the signaling pathways involved in the chagasic cardiac hypertrophy may provide potential targets for pharmacological therapy. Herein, we investigated the implication of focal adhesion kinase (FAK) signaling pathway in triggering hypertrophic phenotype during acute and chronic T. cruzi infection. C57BL/6 mice infected with T. cruzi (Brazil strain) were evaluated for electrocardiographic (ECG) changes, plasma levels of endothelin-1 (ET-1) and activation of signaling pathways involved in cardiac hypertrophy, including FAK and ERK1/2, as well as expression of hypertrophy marker and components of the extracellular matrix in the different stages of T. cruzi infection (60-210 dpi). Heart dysfunction, evidenced by prolonged PR interval and decrease in heart rates in ECG tracing, was associated with high plasma ET-1 level, extracellular matrix remodeling and FAK signaling activation. Upregulation of both FAK tyrosine 397 (FAK-Y397) and serine 910 (FAK-S910) residues phosphorylation as well as ERK1/2 activation, lead to an enhancement of atrial natriuretic peptide gene expression in chronic infection. Our findings highlight FAK-ERK1/2 signaling as a regulator of cardiac hypertrophy in Trypanosoma cruzi infection. Both mechanical stress, induced by cardiac extracellular matrix (ECM) augment and cardiac overload, and ET-1 stimuli orchestrated FAK signaling activation with subsequent activation of the fetal cardiac gene program in the chronic phase of infection, highlighting FAK as an attractive target for Chagas disease therapy.

Formononetin alleviates diabetic cardiomyopathy by inhibiting oxidative stress and upregulating SIRT1 in rats

Objective: To evaluate the effect of formononetin on type 2 diabetic cardiomyopathy. Methods: Diabetes was induced by feeding high-fat diet for 2 weeks and administration of 35 mg/kg of streptozotocin in rats. Formononetin was administered at 10, 20 and 40 mg/kg for 16 weeks once a day. Plasma glucose, lipid parameters, and cardiac markers in blood samples were measured. Body weight and relative heart weight were recorded. Hemodynamic parameters, oxidative stress parameters and silence information regulator 1 (SIRT1) expression in cardiac tissue were estimated. Histopathological changes in cardiac tissue were also observed. Results: Formononetin significantly reduced the levels of glucose, triglycerides, cholesterol, low density lipoprotein, creatine kinase-MB, lactate dehydrogenase and aspartate aminotransferase. In addition, formononetin significantly improved hemodynamic parameters, alleviated oxidative stress and increased SIRT1 expression. Conclusions: The study indicates that formononetin can improve hyperglycemia and hyperlipemia, reduce oxidative stress and increase SIRT1 expression. It can be a potential therapeutic agent for diabetic cardiomyopathy.

High-intensity interval training for treating pathological cardiac hypertrophy in spontaneously hypertensive rats: Effects and mechanisms / 中国组织工程研究

BACKGROUND: Regular exercise training possesses health promotion effect. Low-to-moderate intensity continuous aerobic exercise has been an important strategy for primary and secondary prevention of chronic diseases such as hypertension; however, the effect of high-intensity interval training is still debated. OBJECTIVE: To explore the effects of high-intensity interval training on pathological cardiac hypertrophy and investigate the possible mechanism in spontaneously hypertensive rats. METHODS: Thirty male spontaneously hypertensive rats were randomly assigned into a control group and a training group. Fifteen Wistar-Kyoto rats were used as normotensive group. Rats in the normotensive and control group were housed at rest, while those in the training group were subjected to a high-intensity interval training lasting for 8 weeks. After experiment, blood pressure was detected using a non-invasive blood pressure tester, and cardiac structure and function were measured by echocardiogram. Histopathological detection was performed by hematoxylin-eosin and Masson staining to determine myocardial cross-sectional area. mRNA expression of fetal genes including atrial natriuretic peptide and brain natriuretic peptide were detected by RT-PCR. Protein expression of PI3-K, Akt, CnAβ and NFATc3 was detected using western blot assay. RESULTS AND CONCLUSION: Compared with the normotensive group, the blood pressure level was significantly elevated (P 0.05) in the control group. Compared with the control group, the blood systolic pressure was lowered (P 0.05). Therefore, the 8-week high-intensity interval training can induce the transfer from pathological hypertrophy to physiological hypertrophy and enhance heart function in spontaneously hypertensive rats via the activation of PI3-K/Akt signal transduction pathway; however, the Cn/NFAT pathway cannot be inhibited.

Formononetin alleviates diabetic cardiomyopathy by inhibiting oxidative stress and upregulating SIRT1 in rats

Objective: To evaluate the effect of formononetin on type 2 diabetic cardiomyopathy.Methods: Diabetes was induced by feeding high-fat diet for 2 weeks and administration of 35 mg/kg of streptozotocin in rats. Formononetin was administered at 10, 20 and 40 mg/kg for 16 weeks once a day. Plasma glucose, lipid parameters, and cardiac markers in blood samples were measured. Body weight and relative heart weight were recorded. Hemodynamic parameters, oxidative stress parameters and silence information regulator 1 (SIRT1) expression in cardiac tissue were estimated. Histopathological changes in cardiac tissue were also observed. Results: Formononetin significantly reduced the levels of glucose, triglycerides, cholesterol, low density lipoprotein, creatine kinase-MB, lactate dehydrogenase and aspartate aminotransferase. In addition, formononetin significantly improved hemodynamic parameters, alleviated oxidative stress and increased SIRT1 expression. Conclusions: The study indicates that formononetin can improve hyperglycemia and hyperlipemia, reduce oxidative stress and increase SIRT1 expression. It can be a potential therapeutic agent for diabetic cardiomyopathy.

Effects of cistanche phenylethanol glycosides on the cardiac hypertrophy and PI3K/PKB signaling pathway in rats with pressure overload / 中国药理学通报

Aim To investigate the inhibitory effect of cistanche phenylethanol glycosides (CPhGs) on cardiac hypertrophy in rats caused by pressure overload and its related mechanism. Methods Male SD rats(n =70) were randomly divided into control group (Con), sham operation group (Sham), model group (Mod), positive control group (Vst), and different CPhGs dosage (125, 250, 500 mg • kg-1) groups. Cardiac ultrasound indexes, heart-weight to body-weight index (HWI), cardiac histopathological changes, and the area of myocardical cells (AMC) were detected. Plasma ET-1 and BNP levels were detected by Elisa, and protein expressions of phosphorylated PI3K(p-PI3K), PI3K, phosphorylated PKB (p-pKB) and PKB were detected by Western blot. Results Compared with Mod group, LVPWT, HWI, plasma ET-1, BNP and AMC decreased to different degrees. LVEDD, LVEF, LVFS, the protein expressions of myocardial tissues pPI3K and p-PKB increased to different degrees in CPhGs groups. Moreover, the indexes of CPhGs 250 and 500 mg • kg-1 groups were significantly improved compared to those of Mod group (P < 0. 05 or 0. 01). Compared with Vst group, there were no significant difference in CPhGs 500 mg • kg-1 group. Conclusions CPhGs could inhibit cardiac hypertrophy in rats induced by pressure overload, which might be related to the activation of PI3K/PKB signaling pathway.

Role and mechanism of platelet-derived growth factor/AKT pathway in pressure overload-induced ventricular remodeling / 中国临床药理学与治疗学

AIM: To analyze the role and mechanism of PDGF/AKT pathway in pressure overload-induced ventricular remodeling. METHODS: A total of 55 C57BL/6 female mice were selected to establish aortic arch narrowing model. Forty-five models were successfully modeled. The randomized digital table method was used to divide the models into sham operation group, DMSO group and experimental group. The sham operation group was opened after chest operation. The suture was performed without aortic coarctation (TAC). After 24 hours of thoracotomy, 200 μL of PBS solution and 50 μL of DMSO were administered. The DMSO group was given 200 μL of PBS solution and 50 μL of DMSO 24 h after operation. The experimental group was given PBS solution 200 μL plus AG1296 50 μL 24 h after TAC to observe the heart function and myocardial histopathology of mice. Lentiviral infection was established to identify and culture HUVEC cells with different expression of PDGF gene. According to different treatments, the cells were divided into control group, PDGF group, shRNA group and PDGF+IMA group to detect the expression of p-AKT and t-AKT protein in HUVEC cells. RESULTS:LVESV, LVEDV, LVESD and LVEDD were increased in DMSO group as compared with sham operation group, while EF and FS of DMSO group were lower than those in sham operation group. LVESV, LVEDV, LVESD and LVEDD were lower in experimental group than those in DMSO group, while EF and FS in experimental group were higher than those in DMSO group. The difference was statistically significant (P<0.05). The sham operation group had neatly arranged myocardial tissue and normal interstitial; the DMSO group had irregular morphology, inflammatory cell infiltration, cell gap was enlarged, and the nucleus was deeply stained. The number of expanded or necrotic cells in experimental group decreased, the gap became smaller, and the inflammatory infiltration decreased. The cross-sectional area of myocardial cells in DMSO group was higher than that in sham operation group. The cross-sectional area of the myocardial cells in experimental group was lower than that in DMSO group (P<0.05). The expression of p-AKT and t-AKT protein in PDGF+IMA group was significantly higher than that in PDGF group and shRNA group, the difference was statistically significant (P<0.05). CONCLUSION:PDGF can accelerate ventricular remodeling induced by pressure overload and promote the formation of myocardial fibrosis, while inhibiting PDGF/AKT pathway can improve myocardial cell hypertrophy.

Aliskiren attenuates cardiac dysfunction by modulation of the mTOR and apoptosis pathways

Aliskiren (ALS) is well known for its antihypertensive properties. However, the potential underlying the molecular mechanism and the anti-hypertrophic effect of ALS have not yet been fully elucidated. The aim of the present study was to investigate the role of ALS in mammalian target of rapamycin (mTOR) and apoptosis signaling using in vivo and in vitro models of cardiac hypertrophy. A rat model of cardiac hypertrophy was induced by isoproterenol treatment (5 mg·kg-1·day-1) for 4 weeks, with or without ALS treatment at 20 mg·kg-1·day-1. The expression of hypertrophic, fibrotic, and apoptotic markers was determined by RT-qPCR. The protein expression of apoptotic markers mTOR and p-mTOR was assessed by western blot analysis. The proliferation of H9C2 cells was monitored using the MTS assay. Cell apoptosis was analyzed using flow cytometry. In vivo, isoproterenol-treated rats exhibited worse cardiac function, whereas ALS treatment reversed these dysfunctions, which were associated with changes in p-mTOR, Bcl-2, Bax, and cleaved caspase-3 expression, as well as the number of apoptotic cells. In vitro, H9C2 cardiomyocyte viability was significantly inhibited and cardiac hypertrophy was induced by Ang II administration, but ALS reversed Ang II-induced H9C2 cardiomyocyte hypertrophy and death. Furthermore, Ang II triggered the activation of the mTOR and apoptosis pathways in hypertrophic cardiomyocytes that were inhibited by ALS treatment. These results indicated that ALS alleviated cardiac hypertrophy through inhibition of the mTOR and apoptosis pathways in cardiomyocytes.