Hypertension, Left Ventricular Hypertrophy, and Myocardial Ischemia

Progress in diagnosis and treatment of hypertension combined with left ventricular hypertrophy

BACKGROUND

Hypertension, a worldwide cardiovascular issue, is known to result in significant damage to the left ventricle. Left ventricular hypertrophy refers to an increase in ventricular mass, which is not only the primary independent risk factor for cardiovascular disease onset but also independently related to the risk of death.

OBJECTIVES

We sought to synthesize the existing literature on the occurrence and correlation between hypertension and left ventricular hypertrophy and the progress.

METHODS

A scoping review was performed based on the methodological framework developed by Arksey & O'Malley. Search in the Pubmed database with no language restrictions, as of September 1, 2024.

RESULTS

Of the 8110 articles retrieved, 110 were finally included. The selected articles were published between 1987 and 2024, with 55.5% (61/110) of the studies in the last five years and 14.5% (16/110) of 2024. The studies covered diagnosis, epidemiology, pathophysiology, prognosis, and treatment of hypertension with left ventricular hypertrophy.

CONCLUSION

The literature reviewed suggests that studies on hypertension combined with left ventricular hypertrophy covered a variety of clinical progress, especially the clinical trial results of some new drugs that may bring great hope for treatment.

Exposome-Wide Ranking to Uncover Environmental Chemicals Associated with Dyslipidemia: A Panel Study in Healthy Older Chinese Adults from the BAPE Study

BACKGROUND

Environmental contaminants (ECs) are increasingly recognized as crucial drivers of dyslipidemia and cardiovascular disease (CVD), but the comprehensive impact spectrum and interlinking mechanisms remain uncertain.

OBJECTIVES

We aimed to systematically evaluate the association between exposure to 80 ECs across seven divergent categories and markers of dyslipidemia and investigate their underpinning biomolecular mechanisms via an unbiased integrative approach of internal chemical exposome and multi-omics.

METHODS

A longitudinal study involving 76 healthy older adults was conducted in Jinan, China, and participants were followed five times from 10 September 2018 to 19 January 2019 in 1-month intervals. A broad spectrum of seven chemical categories covering the prototypes and metabolites of 102 ECs in serum or urine as well as six serum dyslipidemia markers [total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, apolipoprotein (Apo)A1, ApoB, and ApoE4] were measured. Multi-omics, including the blood transcriptome, serum/urine metabolome, and serum lipidome, were profiled concurrently. Exposome-wide association study and the deletion/substitution/addition algorithms were applied to explore the associations between 80 EC exposures detection frequency > 50 % and dyslipidemia markers. Weighted quantile sum regression was used to assess the mixture effects and relative contributions. Multi-omics profiling, causal inference model, and pathway analysis were conducted to interpret the mediating biomolecules and underlying mechanisms. Examination of cytokines and electrocardiograms was further conducted to validate the observed associations and biomolecular pathways.

RESULTS

Eight main ECs [1-naphthalene, 1-pyrene, 2-fluorene, dibutyl phosphate, tri-phenyl phosphate, mono-(2-ethyl-5-hydroxyhexyl) phthalate, chromium, and vanadium] were significantly associated with most dyslipidemia markers. Multi-omics indicated that the associations were mediated by endogenous biomolecules and pathways, primarily pertinent to CVD, inflammation, and metabolism. Clinical measures of cytokines and electrocardiograms further cross-validated the association of these exogenous ECs with systemic inflammation and cardiac function, demonstrating their potential mechanisms in driving dyslipidemia pathogenesis.

DISCUSSION

It is imperative to prioritize mitigating exposure to these ECs in the primary prevention and control of the dyslipidemia epidemic. https://doi.org/10.1289/EHP13864.

Metformin induction of heat shock factor 1 activation and the mitochondrial unfolded protein response alleviate cardiac remodeling in spontaneously hypertensive rats

Heart failure and cardiac remodeling are both characterized by mitochondrial dysfunction. Healthy mitochondria are required for adequate contractile activity and appropriate regulation of cell survival. In the mammalian heart, enhancement of the mitochondrial unfolded protein response (UPRmt) is cardioprotective under pressure overload conditions. We explored the UPRmt and the underlying regulatory mechanism in terms of hypertension-induced cardiac remodeling and the cardioprotective effect of metformin. Male spontaneously hypertensive rats and angiotensin II-treated neonatal rat cardiomyocytes were used to induce cardiac hypertrophy. The results showed that hypertension induced the formation of aberrant mitochondria, characterized by a reduced mtDNA/nDNA ratio and swelling, as well as lower levels of mitochondrial complexes I to V and inhibition of the expression of one protein subunit of each of complexes I to IV. Such changes eventually enlarged cardiomyocytes and increased cardiac fibrosis. Metformin treatment increased the mtDNA/nDNA ratio and regulated the UPRmt, as indicated by increased expression of activating transcription factor 5, Lon protease 1, and heat shock protein 60, and decreased expression of C/EBP homologous protein. Thus, metformin improved mitochondrial ultrastructure and function in spontaneously hypertensive rats. In vitro analyses revealed that metformin reduced the high levels of angiotensin II-induced mitochondrial reactive oxygen species in such animals and stimulated nuclear translocation of heat shock factor 1 (HSF1). Moreover, HSF1 small-interfering RNA reduced the metformin-mediated improvements in mitochondrial morphology and the UPRmt by suppressing hypertrophic signals and cardiomyocyte apoptosis. These results suggest that HSF1/UPRmt signaling contributes to the beneficial effects of metformin. Metformin-mediated targeting of mitochondrial protein homeostasis and modulation of HSF1 levels have potential therapeutic implications in terms of cardiac remodeling.

Computed tomography myocardial perfusion imaging to detect myocardial ischemia in patients with anxiety and obstructive coronary heart disease post-exposure to mental stressors

This study aims to measure myocardial blood flow (MBF) using dynamic CT- myocardial perfusion imaging (CT-MPI) combined with mental stressors in patients with obstructive coronary artery disease (OCAD) and in patients with anxiety and no obstructive coronary artery disease (ANOCAD). A total of 30 patients with OCAD with 30 patients with ANOCAD were included in this analysis. Using the 17-segment model, the rest and stress phase MBF of major coronary arteries in participants were recorded respectively. Compared with ANOCAD patients, OCAD patients were more likely to have localized reduction of MBF (p < 0.05). For patients with ANOCAD, both global MBF and MBF of the main coronary arteries in the stress phase were lower than those in the rest phase (all p < 0.05), but there was no significant difference in MBF among the main coronary arteries in the rest or stress phase (p = 0.25, p = 0.15). For patients with OCAD, the MBF of the target area was lower than that of the non-target area in both the rest and stress phase, and the MBF of the target area in the stress phase was lower than that in the rest phase (all p < 0.05). However, there was no significant difference in MBF between the rest or stress phase in the non-target area (p = 0.73). Under mental stress, the decrease in MBF in ANOCAD patients was diffuse, while the decrease in MBF in OCAD patients was localized. Dynamic CT-MPI combined with mental stressors can be used to detect MBF changes in anxiety patients.

Astragalus (Astragalus mongholicus) Improves Ventricular Remodeling via ESR1 Downregulation RhoA/ROCK Pathway

Astragalus (Astragalus mongholicus) alleviates myocardial remodeling caused by hypertension. However, the detailed molecular mechanism is unclear. This study aims to investigate the effect of Astragalus on ventricular remodeling in ovariectomized spontaneous hypertensive rats (OVX-SHR).Female SHR/NCrl rats were subjected to bilateral ovariectomy to establish the OVX-SHR model and treated with Astragalus extract by gavage. The hemodynamics and cardiac function parameters were measured. HE and Masson staining were used to detect the pathological structure of myocardial remodeling and observe the hyperplasia of myocardial collagen fibers. The immunohistochemistry tested the level of α-SMA. The expression levels of inflammatory cytokines, IκB, p65, Cleaved-Caspase3, RhoA, and ROCK1/2 were detected using Western blot. The method of qRT-PCR measured the expression of matrix metalloproteinase (MMP-2 and MMP-9).Hemodynamic and cardiac function parameters were significantly improved after a high dose of Astragalus extract and Valsartan treatment. The myocardial integrity of the model group was significantly reduced, arranged loosely, and disordered, while the expression of α-SMA was increased. However, Astragalus extract and Valsartan treatments significantly reduced the pathological damage and α-SMA. The levels of TNF-α, IL-1β, IL-6, TGF-β, MMP-2, and MMP-9 in the model group were increased but decreased after Astragalus extract treatment. Adding an ESR1 inhibitor attenuated the improvement effect of Astragalus extract on myocardial remodeling and restored the expression of RhoA and ROCK1/2.Astragalus extract attenuates the cardiac damage in OVX-SHR by downregulating the RhoA/ROCK pathway through ESR1.

Interventricular Septum Thickness for the Prediction of Coronary Heart Disease and Myocardial Infarction in Hypertension Population: A Prospective Study

The aim of the present study was to evaluate the prognostic value of interventricular septum thickness (IVSd) on the incidence of cardiovascular diseases. Based on the general population in Northeast China, 10,349 participants were successfully followed up for echocardiography over a median follow-up time of 4.66 years, among which 4801 were hypertensive. Coronary heart disease (CHD) and myocardial infarction (MI) incidence were followed up. Cox proportional hazards models were used to estimate the association of the baseline IVSd with adverse outcomes. IVS hypertrophy increased incident rates of CHD and MI compared with normal IVSd in the overall population and in the female sex-stratification group. In males, IVS hypertrophy had parallel increase rates of CHD (all p < 0.05). Kaplan−Meier analysis showed that IVS hypertrophy could predict CHD and MI incidence and CHD-free and MI-free survival. Multivariable Cox analysis revealed that IVS hypertrophy was correlated with CHD incidence (HR = 1.155, 95% CI = 1.155−2.861, p = 0.01) and MI incidence (HR = 2.410, 95% CI = 1.303−4.458, p = 0.005). In women, IVS hypertrophy was independently associated with CHD and MI incidence (all p < 0.05). Our prospective cohort study illustrated that IVS hypertrophy detected by echocardiography has a prognostic significance for CHD and MI. Therefore, the early detection of IVSd should be conducted to avoid adverse outcomes in further clinical practice.

LncRNA Gm43843 Promotes Cardiac Hypertrophy via miR-153-3p/Cacna1c Axis

Long noncoding RNAs (lncRNAs) have been reported to engage in many human diseases, including cardiac hypertrophy. Cardiac hypertrophy was mainly caused by excessive pressure load, which can eventually lead to a decline in myocardial contractility. Gm43843, a novel lncRNA, has not been well explored in cardiac hypertrophy so far. Herein, we are going to search the function and the underlying molecular mechanism of Gm43843 in cardiac hypertrophy. Gm43843 levels were measured via qRT-PCR in mouse myocardial cells when they are treated with angiogenin II (Ang II) or transfected with different plasmids. Western blot assay was implemented to detect the cardiac hypertrophy-related protein markers, while the cell was analyzed via immunofluorescence (IF) assay to evaluate the hypertrophy. Meanwhile, the binding of Gm43843 and the putative targets was examined based on mechanistic assay results. We found that Gm43843 expression was increased with the elevated concentration of Ang II. Inhibited Gm43843 was detected to reduce the hypertrophy of mouse myocardial cells. Meanwhile, Gm43843/miR-153-3p/Cacna1c axis was found to modulate cardiac hypertrophy. In short, Gm43843 promotes cardiac hypertrophy via miR-153-3p/Cacna1c axis.

Dexmedetomidine attenuates hypoxia-induced cardiomyocyte injury by promoting telomere/telomerase activity: Possible involvement of ERK1/2-Nrf2 signaling pathway

Dexmedetomidine (Dex), an α2-adrenergic receptor (α2-AR) agonist, possesses cardioprotection against ischaemic/hypoxic injury, but the exact mechanism is not fully elucidated. Since telomere/telomerase dysfunction is involved in myocardial ischemic damage, the present study aimed to investigate whether Dex ameliorates cobalt chloride (CoCl_2; a hypoxia mimic agent in vitro)-induced the damage of H9c2 cardiomyocytes by improving telomere/telomerase dysfunction and further explored the underlying mechanism focusing on ERK1/2-Nrf2 signaling pathway. Result showed that Dex increased cell viability, decreased apoptosis, and reduced cardiomyocyte hypertrophy as illustrated by the decreases in cell surface area and the biomarker levels for cardiac hypertrophy including atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and myosin heavy chain β (β-MHC) mRNA and protein in CoCl₂ -exposed H9c2 cells. Intriguingly, Dex increased the telomere length and telomerase activity as well as telomere reverse transcriptase (TERT) protein and mRNA levels in H9c2 cells exposed to CoCl₂ , indicating that Dex promotes telomere/telomerase function under hypoxia. In addition, Dex remarkably diminished the ROS generation, reduced MDA content, and increased antioxidative signaling as evidenced by the increases in SOD and GSH-Px activities. Furthermore, Dex increased the ratio of P-ERK1/2/T-ERK1/2 and P-Nrf2/T-Nrf2 and enhanced Nrf2 nuclear translocation in CoCl₂ -subjected H9c2 cells, suggesting that Dex promotes the activation of the ERK1/2-Nrf2 signaling pathway. These novel findings indicated that Dex attenuates myocardial ischemic damage and reduces myocardial hypertrophy by promoting telomere/telomerase function, which may be associated with the activation of the ERK1/2-Nrf2 signaling pathway in vitro. This article is protected by copyright. All rights reserved.

Expression Profiles of Circular RNA in Aortic Vascular Tissues of Spontaneously Hypertensive Rats

Background: Circular RNAs (circRNAs), as a kind of endogenous non-coding RNA, have been implicated in ischemic heart diseases and vascular diseases. Based on theirs high stability with a closed loop structure, circRNAs function as a sponge and bind specific miRNAs to exert inhibitory effects in heart and vasculature, thereby regulating their target gene and protein expression, via competitive endogenous RNA (ceRNA) mechanism. However, the exact roles and underlying mechanisms of circRNAs in hypertension and related cardiovascular diseases remain largely unknown. Methods and Results: High-throughput RNA sequencing (RNA-seq) was used to analyze the differentially expressed (DE) circRNAs in aortic vascular tissues of spontaneously hypertensive rats (SHR). Compared with the Wistar-Kyoto (WKY) rats, there were marked increases in the levels of systolic blood pressure, diastolic blood pressure and mean blood pressure in SHR under awake conditions via the tail-cuff methodology. Totally, compared with WKY rats, 485 DE circRNAs were found in aortic vascular tissues of SHR with 279 up-regulated circRNAs and 206 down-regulated circRNAs. Furthermore, circRNA-target microRNAs (miRNAs) and the target messenger RNAs (mRNAs) of miRNAs were predicted by the miRanda and Targetscan softwares, respectively. Additionally, real-time RT-PCR analysis verified that downregulation of rno_circRNA_0009197, and upregulation of rno_circRNA_0005818, rno_circRNA_0005304, rno_circRNA_0005506, and rno_circRNA_0009301 were observed in aorta of SHR when compared with that of WKY rats. Then, the potential ceRNA regulatory mechanism was constructed via integrating 5 validated circRNAs, 31 predicted miRNAs, and 266 target mRNAs. More importantly, three hub genes (NOTCH1, FOXO3, and STAT3) were recognized according to PPI network and three promising circRNA-miRNA-mRNA regulatory axes were found in hypertensive rat aorta, including rno_circRNA_0005818/miR-615/NOTCH1, rno_circRNA_0009197/ miR-509-5p/FOXO3, and rno_circRNA_0005818/miR-10b-5p/STAT3, respectively. Conclusions: Our results demonstrated for the first time that circRNAs are expressed aberrantly in aortic vascular tissues of hypertensive rats and may serve as a sponge linking with relevant miRNAs participating in pathogenesis of hypertension and related ischemic heart diseases via the circRNA-miRNA-mRNA ceRNAnetwork mechanism.

Levels of Serum sST2, MMP-3, and Gal-3 in Patients with Essential Hypertension and Their Correlation with Left Ventricular Hypertrophy

Essential hypertension (EH) is a clinically frequent cardiovascular disease, with insidious onset, causing increased pressure load and neuroregulation disorders in patients. Long-term EH can cause left ventricular hypertrophy (LVH), which can lead to arrhythmia and even death. The soluble suppression of tumorigenicity 2 (sST2), matrix metalloproteinase-3 (MMP-3), and galectin-3 (Gal-3) in serum plays an important role in the occurrence, development, and prognosis of cardiovascular diseases. In our study, we divided EH patients into 3 levels and groups with or without LVH, according to their condition. The levels of sST2, MMP-3, and Gal-3 in the serum were measured in different groups of patients. Our results showed that the levels of sST2, MMP-3, and Gal-3 in the serum increased progressively with the level in different EH groups. The levels of sST2, MMP-3, and Gal-3 in the serum of the LVH group were higher than those of the NLVH group, and it is positively correlated with LVH-related indexes. The risk of developing and progressing to LVH in patients with EH can be determined by the method of measuring three indicators.

Morphological Study of the Effect of Aerobic Exercise on Organs and Arteries in Spontaneously Hypertensive Rats

Hypertension is usually accompanied by the impairment of organs and arteries, and seriously threatens human health. Aerobic exercise can effectively prevent and treat hypertension. However, the mechanism of exercise therapy in hypertension is still unclear. In this study, we explored how aerobic exercise effectively reversed the impairment of the heart, kidney, and arteries caused by hypertension through a pathomorphological perspective. Spontaneously hypertensive rats were subjected to fifteen weeks of 45 min and 90 min swimming training without weight, and we then tested the effect of exercise on the morphology and structure of the heart, kidney, iliac artery, and branch of the mesenteric artery. We found that the myocardial fibers became thinner, the cross-sectional area of myocardial cells decreased, and cardiomyocyte edema disappeared after 45 min of aerobic exercise. Additionally, the pathological microstructure of glomeruli and renal tubules were improved. At the same time, aerobic exercise could also reverse the morphology and structure of arteries and mesenteric artery branches in spontaneously hypertensive rats.

Neither Preoperative Pulse Pressure nor Systolic Blood Pressure Is Associated With Cardiac Complications After Coronary Artery Bypass Grafting

BACKGROUND

Increased pulse pressure has been associated with adverse cardiovascular events, cardiac and all-cause mortality in surgical and nonsurgical patients. Whether increased pulse pressure worsens myocardial injury and dysfunction after cardiac surgery, however, has not been fully characterized. We examined whether cardiac surgical patients with elevated pulse pressure are more susceptible to myocardial injury, dysfunction, cardiac-related complications, and mortality. Secondarily, we examined whether pulse pressure was a stronger predictor of the outcomes than systolic blood pressure.

METHODS

This retrospective observational study included adult cardiac surgical patients having elective isolated on-pump coronary artery bypass grafting (CABG) between 2010 and 2017 at the Cleveland Clinic. The association between elevated pulse pressure and (1) perioperative myocardial injury, measured by postoperative troponin-T concentrations, (2) perioperative myocardial dysfunction, assessed by the requirement for perioperative inotropic support using the modified inotropic score (MIS), and (3) cardiovascular complications assessed by the composite outcome of postoperative mechanical circulatory assistance or in-hospital mortality were assessed using multivariable linear regression models. Secondarily, the association between pulse pressure versus systolic blood pressure and the outcomes were compared.

RESULTS

Of 2704 patients who met the inclusion/exclusion criteria, complete data were available for 2003 patients. Increased pulse pressure over 40 mm Hg was associated with elevated postoperative troponin-T level, estimated to be 1.05 (97.5% confidence interval [CI], 1.02-1.09; P < .001) times higher per 10 mm Hg increase in pulse pressure. The association between pulse pressure and myocardial dysfunction and the composite outcome of cardiovascular complications and death were not significant. There was no difference in the association with pulse pressure versus systolic blood pressure and troponin-T concentrations.

CONCLUSIONS

Elevated preoperative pulse pressure was associated with a modest increase in postoperative troponin-T concentrations, but not postoperative cardiovascular complications or in-hospital mortality in patients having CABG. Pulse pressure was not a better predictor than systolic blood pressure.

Effect of Irisin on Pressure Overload-Induced Cardiac Remodeling

BACKGROUND

Irisin has been considered a prognostic factor in several cardiovascular diseases. Nevertheless, no data are available on the role of irisin in cardiac remodeling.

AIM OF THE STUDY

This study aimed to determine the potential role of irisin in cardiac remodeling and explore potential mechanisms.

METHODS

A total of 40 rats that underwent transverse abdominal aortic constriction (TAC) surgery or sham operation were divided into four groups: sham + saline (NS), sham + irisin, TAC + NS, and TAC + irisin. After 6 weeks of treatment, echocardiography was performed to assess in vivo cardiac morphology. The left ventricular myocardium was prepared and observed by pathological examination. The effect of irisin on cardiomyocyte apoptosis and the expression of oxidative stress and cardiac hypertrophy markers were observed. Then, the effect of irisin on the Akt signaling system was also detected.

RESULTS

The rats in the TAC group displayed obvious signs of cardiac dysfunction and cardiac hypertrophy, and irisin treatment could reverse these changes. Irisin could inhibit the expression of nicotinamide adenine dinucleotide phosphate oxidase 2 and xanthine oxidase in TAC rats and increase the expression of antioxidant enzymes. Furthermore, the expression of phosphorylated protein kinase B (p-Akt), phosphorylated mammalian target of rapamycin (p-mTOR), and phosphorylated glycogen synthase kinase 3β (p-GSK3β) was much higher in the cardiac remodeling groups (p <0.05 vs. sham rats). Irisin could relieve the inhibition effect and reduce the expression level of these three proteins.

CONCLUSIONS

Irisin treatment could significantly improve cardiac remodeling by inhibiting oxidative stress via attenuating the Akt signaling activation.

Left ventricular hypertrophy is associated with overexpression of HSP60, TLR2, and TLR4 in the myocardium

Left ventricular hypertrophy is a common adaptive response to increased cardiac workload. Cardiomyocytes growth and increase in contractile force are conditioned by sufficient energy production, which implies appropriate mitochondrial function. The 60 kDa heat shock protein (HSP60) is a chaperone essential for mitochondrial proteostasis, but when translocates from mitochondria, it can also act as a potent inflammatory mediator binding to toll-like receptors (TLRs). In this study, we aimed to compare the expression pattern of HSP60, TLR2, and TLR4 in hypertrophic vs non-hypertrophic, normal human myocardium. We further examined whether HSP60 in situ binds to TLRs in hypertrophic myocardial tissue. In addition, expression of activated downstream targets of TLR 2/4 pathways was also evaluated.For this purpose, immunohistochemical expression analyses were performed on myocardial tissue samples obtained during the autopsy of human subjects in which left ventricular hypertrophy was the only cardiopathological finding and had died from sudden cardiac death, as well as from the subjects without any cardiac pathology, that died by unnatural death (accident or suicide). Double immunofluorescence was used to examine HSP60 translocation, while proximity ligation assay (PLA) was performed to assess HSP60 and TLRs interactions.Hypertrophic myocardium showed significantly higher expression of HSP60, TLR2, and TLR4 compared to normal myocardium. Furthermore, in hypertrophic cardiomyocytes, we found membrane translocation of HSP60 and signs of HSP60/TLR interactions.Conclusion: The obtained data point to an important supportive role of HSP60 in adaptive cardiomyocytes growth, while concomitant induction of TLR2 and TLR4 candidates HSP60-TLRs interactions as an early events during pathogenesis of secondary complications consequently to the left ventricular hypertrophy.

Mechanism of tanshinones and phenolic acids from Danshen in the treatment of coronary heart disease based on co-expression network

Background

The tanshinones and phenolic acids in Salvia miltiorrhiza (also named Danshen) have been confirmed for the treatment of coronary heart disease (CHD), but the action mechanisms remain elusive.

Methods

In the current study, the co-expression protein interaction network (Ce-PIN) was used to illustrate the differences between the tanshinones and phenolic acids of Danshen in the treatment of CHD. By integrating the gene expression profile data and protein-protein interactions (PPIs) data, the Ce-PINs of tanshinones and phenolic acids were constructed. Then, the Ce-PINs were analyzed by gene ontology enrichment analyzed based on the optimal algorithm.

Results

It turned out that Danshen is able to treat CHD by regulating the blood circulation, immune response and lipid metabolism. However, phenolic acids may regulate the blood circulation by Extracellular calcium-sensing receptor (CaSR), Endothelin-1 receptor (EDNRA), Endothelin-1 receptor (EDNRB), Kininogen-1 (KNG1), tanshinones may regulate the blood circulation by Guanylate cyclase soluble subunit alpha-1 (GUCY1A3) and Guanylate cyclase soluble subunit beta-1 (GUCY1B3). In addition, both the phenolic acids and tanshinones may regulate the immune response or inflammation by T-cell surface glycoprotein CD4 (CD4), Receptor-type tyrosine-protein phosphatase C (PTPRC).

Conclusion

Through the same targets of the same biological process and different targets of the same biological process, the tanshinones and phenolic acids synergistically treat coronary heart disease.

Higher left ventricular mass-wall stress-heart rate product and outcome in aortic valve stenosis

OBJECTIVE

Whether increased myocardial oxygen demand could help explain the association of left ventricular (LV) hypertrophy with higher adverse event rate in patients with aortic valve stenosis (AS) is unknown.

METHODS

Data from 1522 patients with asymptomatic mostly moderate AS participating in the Simvastatin-Ezetimibe in AS study followed for a median of 4.3 years was used. High LV mass-wall stress-heart rate product was identified as >upper 95% CI limit in normal subjects. The association of higher LV mass-wall stress-heart rate product with major cardiovascular (CV) events, combined CV death and hospitalised heart failure and all-cause mortality was tested in Cox regression analyses, and reported as HR and 95% CI.

RESULTS

High LV mass-wall stress-heart rate product was found in 19% at baseline, and associated with male sex, higher body mass index, hypertension, LV hypertrophy, more severe AS and lower LV ejection fraction (all p<0.01). Adjusting for these confounders in time-varying Cox regression analysis, 1 SD higher LV mass-wall stress-heart rate product was associated with higher HR of major CV events (HR 1.16(95% CI 1.06 to 1.29)), combined CV death and hospitalised heart failure (HR 1.29(95% CI 1.09 to 1.54)) and all-cause mortality (HR 1.34(95% CI 1.13 to 1.58), all p<0.01).

CONCLUSION

In patients with initially mild-moderate AS, higher LV mass-wall stress-heart rate product was associated with higher mortality and heart failure hospitalisation. Our results suggest that higher myocardial oxygen demand is contributing to the higher adverse event rate reported in AS patients with LV hypertrophy.

TRIAL REGISTRATION NUMBER

NCT000092677;Post-results.

Danshenol A Alleviates Hypertension-Induced Cardiac Remodeling by Ameliorating Mitochondrial Dysfunction and Suppressing Reactive Oxygen Species Production

Current therapeutic approaches have a limited effect on cardiac remodeling, which is characteristic of cardiac fibrosis and myocardial hypertrophy. In this study, we examined whether Danshenol A (DA), an active ingredient extracted from the traditional Chinese medicine Radix Salviae, can attenuate cardiac remodeling and clarified the underlying mechanisms. Using the spontaneously hypertensive rat (SHR) as a cardiac remodeling model, DA ameliorated blood pressure, cardiac injury, and myocardial collagen volume and improved cardiac function. Bioinformatics analysis revealed that DA might attenuate cardiac remodeling through modulating mitochondrial dysfunction and reactive oxygen species. DA repaired the structure/function of the mitochondria, alleviated oxidative stress in the myocardium, and restored apoptosis of cardiomyocytes induced by angiotensin II. Besides, DA inhibited mitochondrial redox signaling pathways in both the myocardium and cardiomyocytes. Thus, our study suggested that DA attenuates cardiac remodeling induced by hypertension through modulating mitochondrial dysfunction and reactive oxygen species.

Mechanics insights of curcumin in myocardial ischemia: Where are we standing?

Cardiovascular disorders are known as one of the main health problems which are associated with mortality worldwide. Myocardial ischemia (MI) is improper blood supply to myocardium which leads from serious complications to life-threatening problems like AMI, atherosclerosis, hypertension, cardiac-hypertrophy as well as diabetic associated complications as diabetic atherosclerosis/cardiomyopathy/hypertension. Despite several efforts, the current therapeutic platforms are not related with significant results. Hence, it seems, developing novel therapies are required. In this regard, increasing evidences indicated, curcumin (CRC) acts as cardioprotective agent. Given that CRC and its analogs exert their cardioprotective effects via affecting on a variety of cardiovascular diseases-related mechanisms (i.e., Inflammation, and oxidative stress). Herein, for first time, we have highlighted the protective impacts of CRC against MI. This review might be a steppingstone for further investigation into the clinical implications of the CRC against MI. Furthermore, it pulls in light of a legitimate concern for scientific community, seeking novel techniques and characteristic dynamic biopharmaceuticals for use against myocardial ischemia.

Long non-coding RNA cytoskeleton regulator RNA (CYTOR) modulates pathological cardiac hypertrophy through miR-155-mediated IKKi signaling

Pathological cardiac hypertrophy, which may lead to heart failure and sudden death, can be affected by multiple factors. In our previous study, we revealed that IKKi deficiency induced cardiac hypertrophy through the activation of the AKT and NF-kB signaling pathway in response to aortic banding (AB). Non-coding RNAs, mainly long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), play a crucial role in normal developmental and pathological processes. In the present study, microarray analysis results from GEO database were analyzed, and upregulated lncRNAs in cardiac hypertrophy were identified. Of them, lncRNA cytoskeleton regulator RNA (CYTOR) obtained a fold-change of 6.16 and was positively correlated with IKBKE according to the data from The GTEx project. CYTOR knockdown significantly enhanced the inducible effect of AB operation on mice myocardial hypertrophy and Angiotensin II on cardiomyocyte hypertrophy. Moreover, miR-155 was significantly related to hypertrophic cardiomyopathy (HCM, |hsa05410) and predicted to target both CYTOR and IKBKE. Luciferase reporter and RIP assays revealed that CYTOR served as a ceRNA for miR-155 to counteract miR-155-mediated repression of IKBKE. Moreover, CYTOR knockdown reduced IKKi protein levels while activated NF-kB signaling pathway, whereas miR-155 inhibition exerted an opposing effect; the effect of CYTOR could be partially attenuated by miR-155 inhibition. Taken together, CYTOR might play a protective role in cardiac hypertrophy through miR-155 and downstream IKKi and NF-κB signaling, most possibly through serving as a ceRNA for miR-155 to counteract miR-155-mediated repression of IKBKE.

Paeoniflorin improves pressure overload-induced cardiac remodeling by modulating the MAPK signaling pathway in spontaneously hypertensive rats

Paeoniflorin (PF) is a main bioactive component of the root of Paeonia lactiflora Pal, and previous investigations suggest that it may impact cardiac remodeling in spontaneous hypertensive rats (SHR) via the MAPK signaling pathway. Thus, the purpose of this investigation was to examine the impacts of paeoniflorin cardiac function in SHR rats. Cardiac function and blood pressure were observed using echocardiography and non-invasive tail pressure gauge. Heart histopathology was assessed by histological staining and transmission electron microscopy. Genomic sequencing was performed and signaling pathway enrichment analyzed the function of differentially expressed genes(DEGs). Biochemical kits were used to analyze the serum level of proinflammatory cytokines including TNF-α, IL-6 and MCP-1. qRT-PCR proved the mRNA expression of Ngfr, Grin2b, and Ntf4. MAPK pathways were determined via western blot. Paeoniflorin decreased blood pressure and increased hemodynamic indexes. 131 DEGs were identified (SHR vs. PF), and mainly enriched on the MAPK signaling pathway. Paeoniflorin reduced IL-6, MCP-1, Ngfr, Grin2b, and Ntf4, and also decreased p-JNK, p-Erk1/2, and p-p38 proteins compared with the SHR group. Paeoniflorin attenuated cardiac hypertrophy, cardiac fibrosis, and inflammation, and subsequently improved LV function. In conclusion, the cardioprotective role of paeoniflorin was associated with the inhibition of MAPK signaling pathway.

Exogenous Hydrogen Sulfide Supplement Attenuates Isoproterenol-Induced Myocardial Hypertrophy in a Sirtuin 3-Dependent Manner

Hydrogen sulfide (H₂S) is a gasotransmitter with a variety of cardiovascular protective effects. Sirtuin 3 (SIRT3) is closely related to mitochondrial function and oxidative stress. We found that NaHS increased SIRT3 expression in the preventive effect on isoproterenol- (ISO-) induced myocardial hypertrophy. We further investigated whether exogenous H₂S supplement improved ISO-induced myocardial hypertrophy in a SIRT3-dependent manner. 10-week-old male 129S1/SvImJ (WT) mice and SIRT3 knockout (KO) mice were intraperitoneally injected with NaHS (50 μmol/kg/d) for two weeks and then intraperitoneally injected with ISO (60 mg/kg/d) for another two weeks. In WT mice, NaHS significantly reduced the cardiac index of ISO-induced mice, decreased the cross-sectional area of cardiomyocytes, and inhibited the expressions of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) mRNA. The activity of total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) in the myocardium was increased, but the level of malondialdehyde (MDA) was decreased. The fluorescence intensity of dihydroethidium staining for superoxide anion was attenuated. Optic atrophy 1 (OPA1) expression was upregulated, while dynamin-related protein 1 (DRP1) expression was downregulated. ERK, but not P38 and JNK, phosphorylation was downregulated. However, all above protective effects were unavailable in ISO-induced SIRT3 KO mice. Our present study suggested that exogenous H₂S supplement inhibited ISO-induced cardiac hypertrophy depending on SIRT3, which might be associated with antioxidant stress.

Autologous endothelial progenitor cell therapy improves right ventricular function in a model of chronic thromboembolic pulmonary hypertension

BACKGROUND

Right ventricular (RV) failure is the main prognostic factor in pulmonary hypertension, and ventricular capillary density (CD) has been reported to be a marker of RV maladaptive remodeling and failure. Our aim was to determine whether right intracoronary endothelial progenitor cell (EPC) infusion can improve RV function and CD in a piglet model of chronic thromboembolic pulmonary hypertension (CTEPH).

METHODS

We compared 3 groups: sham (n = 5), CTEPH (n = 6), and CTEPH with EPC infusion (CTEPH+EPC; n = 5). After EPC isolation from CTEPH+EPC piglet peripheral blood samples at 3 weeks, the CTEPH and sham groups underwent right intracoronary infusion of saline, and the CTEPH+EPC group received EPCs at 6 weeks. RV function, pulmonary hemodynamics, and myocardial morphometry were investigated in the animals at 10 weeks.

RESULTS

After EPC administration, the RV fractional area change increased from 32.75% (interquartile range [IQR], 29.5%-36.5%) to 39% (IQR, 37.25%-46.50%; P = .030). The CTEPH+EPC piglets had reduced cardiomyocyte surface areas (from 298.3 μm² [IQR, 277.4-335.3 μm²] to 234.6 μm² (IQR, 211.1-264.7 μm²; P = .017), and increased CD31 expression (from 3.12 [IQR, 1.27-5.09] to 7.14 [IQR, 5.56-8.41; P = .017). EPCs were found in the RV free wall at 4 and 24 hours after injection but not 4 weeks later.

CONCLUSIONS

Intracoronary infusion of EPC improved RV function and CD in a piglet model of CTEPH. This novel cell-based therapy might represent a promising RV-targeted treatment in patients with pulmonary hypertension.

Irisin alleviates pressure overload-induced cardiac hypertrophy by inducing protective autophagy via mTOR-independent activation of the AMPK-ULK1 pathway

In hypertrophic hearts, autophagic flux insufficiency is recognized as a key pathology leading to maladaptive cardiac remodeling and heart failure. This study aimed to illuminate the cardioprotective role and mechanisms of a new myokine and adipokine, irisin, in cardiac hypertrophy and remodeling. Adult male wild-type, mouse-FNDC5 (irisin-precursor)-knockout and FNDC5 transgenic mice received 4 weeks of transverse aortic constriction (TAC) alone or combined with intraperitoneal injection of chloroquine diphosphate (CQ). Endogenous FNDC5 ablation aggravated and exogenous FNDC5 overexpression attenuated the TAC-induced hypertrophic damage in the heart, which was comparable to the protection of irisin against cardiomyocyte hypertrophy induced by angiotensin II (Ang II) or phenylephrine (PE). Accumulated autophagosome and impaired autophagy flux occurred in the TAC-treated myocardium and Ang II- or PE-insulted cardiomyocytes. Irisin deficiency caused reduced autophagy and aggravated autophagy flux failure, whereas irisin overexpression or supplementation induced protective autophagy and improved autophagy flux, which were reversed by autophagy inhibitors Atg5 siRNA, 3-MA and CQ. Irisin boosted the activity of only AMPK but not Akt and MAPK family members in hypertrophic hearts and cultured cardiomyocytes and further activated ULK1 at Ser555 but not Ser757 and did not affect the mTOR-S6K axis. Blockage of AMPK and ULK1 with compund C and SBI-0206965, respectively, both abrogated irisin's protection against cardiomyocyte hypertrophic injury and reversed its induction of both autophagy and autophagy flux. Our results suggest that irisin protects against pressure overload-induced cardiac hypertrophy by inducing protective autophagy and autophagy flux via activating AMPK-ULK1 signaling.

Structural Determinants for Small-Molecule Activation of Skeletal Muscle AMPK α2β2γ1 by the Glucose Importagog SC4

The AMP-activated protein kinase (AMPK) αβγ heterotrimer regulates cellular energy homeostasis with tissue-specific isoform distribution. Small-molecule activation of skeletal muscle α2β2 AMPK complexes may prove a valuable treatment strategy for type 2 diabetes and insulin resistance. Herein, we report the small-molecule SC4 is a potent, direct AMPK activator that preferentially activates α2 complexes and stimulates skeletal muscle glucose uptake. In parallel with the term secretagog, we propose "importagog" to define a substance that induces or augments cellular uptake of another substance. Three-dimensional structures of the glucose importagog SC4 bound to activated α2β2γ1 and α2β1γ1 complexes reveal binding determinants, in particular a key interaction between the SC4 imidazopyridine 4'-nitrogen and β2-Asp111, which provide a design paradigm for β2-AMPK therapeutics. The α2β2γ1/SC4 structure reveals an interaction between a β2 N-terminal α helix and the α2 autoinhibitory domain. Our results provide a structure-function guide to accelerate development of potent, but importantly tissue-specific, β2-AMPK therapeutics.

Cardiac adaptation to hypertension in adult female Dahl salt-sensitive rats is dependent on ovarian function, but loss of ovarian function does not predict early maladaptation

Aim of study was to examine experimentally the adult female hypertensive heart in order to determine the role of ovary function in the response of the heart to salt-dependent hypertension. Dahl salt-sensitive rats, age 12 weeks, with/without ovariectomy were fed a standard (0.3% NaCl) or high-salt diet (8%) for 16 weeks. Mean arterial blood pressure monitored noninvasively in conscious state increased significantly by high salt. Echocardiography was performed at baseline and endpoint. Heart function and molecular changes were evaluated at endpoint by left ventricle catheterization, by sirius red staining for collagen and by gene expression using quantitative RT-PCR for selected genes. At endpoint, significant concentric hypertrophy was present with high salt. Increase in relative wall thickening with high salt compared to normal diet was more pronounced with intact ovaries (0.33 ± 0.02 and 0.57 ± 0.04 vs. 0.29 ± 0.00 and 0.46 ± 0.03) as was the reduction in midwall fractional shortening (20 ± 0.6 and 14 ± 2 vs. 19 ± 0.9 and 18 ± 1). Ovariectomy increased stroke volume and decreased the ratio of mitral peak velocity of early filling (E) to early diastolic mitral annular velocity (E') (E/E' ratio) when compared to hearts from intact rats. High salt increased expression of collagen I and III genes and perivascular collagen in the heart slightly, but % interstitial collagen by sirius red staining remained unchanged in intact rats and decreased significantly by ovariectomy. Added volume load but not deterioration of function or structure characterized the nonfailing hypertensive heart of salt-sensitive females ovariectomized at mature age when compared to corresponding intact females.

The lncRNA Plscr4 Controls Cardiac Hypertrophy by Regulating miR-214

Cardiac hypertrophy accompanied by maladaptive cardiac remodeling is the uppermost risk factor for the development of heart failure. Long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) have various biological functions, and their vital role in the regulation of cardiac hypertrophy still needs to be explored. In this study, we demonstrated that lncRNA Plscr4 was upregulated in hypertrophic mice hearts and in angiotensin II (Ang II)–treated cardiomyocytes. Next, we observed that overexpression of Plscr4 attenuated Ang II-induced cardiomyocyte hypertrophy. Conversely, the inhibition of Plscr4 gave rise to cardiomyocyte hypertrophy. Furthermore, overexpression of Plscr4 attenuated TAC (transverse aortic constriction)-induced cardiac hypertrophy. Finally, we demonstrated that Plscr4 acted as an endogenous sponge of miR-214 and forced expression of Plscr4 downregulated miR-214 expression to promote Mfn2 and attenuate hypertrophy. In contrast, knockdown of Plscr4 upregulated miR-214 to induce cardiomyocyte hypertrophy. Additionally, luciferase assay showed that miR-214 was the direct target of Plscr4, and overexpression of miR-214 counteracted the anti-hypertrophy effect of Plscr4. Collectively, these findings identify Plscr4 as a negative regulator of cardiac hypertrophy in vivo and in vitro due to its regulation of the miR-214-Mfn2 axis, suggesting that Plscr4 might act as a therapeutic target for the treatment of cardiac hypertrophy and heart failure.