Microvascular and lymphatic dysfunction in HFpEF and its associated comorbidities

Single-cell transcriptome sequencing revealed the metabolic changes and microenvironment changes of cardiomyocytes induced by diabetes

PURPOSE

Diabetes is a chronic metabolic disorder characterized by elevated blood glucose levels. This study aimed to analyze the changes underlying heterogeneities and communication properties of CMs in diabetes mellitus (DM).

METHODS

GSE213337 dataset was retrieved from NCBI Gene Expression Omnibus, containing the single-cell RNA sequencing data of hearts from the control and streptozotocin-induced diabetic mice. GSEA and GSVA were used to explore the function enrichment of DEGs in CM. Cell communication analysis was carried out to study the altered signals and significant ligand-receptor interactions.

RESULTS

Seventeen cell types were identified between DM and the controls. The increasing ratio of CM suggested the occurrence of diabetes induces potential pathological changes of CM proliferation. A total of 1144 DEGs were identified in CM. GSEA and GSVA analysis indicated the enhancing lipid metabolism involving in DM. The results of cell communication analysis suggested that high glucose activated the ability of CM receiving fibroblast and LEC, while inhibited the capacity of receiving ECC and pericyte. Furthermore, GAS and ANGPTL were significantly decreased under DM, which was consistent with the results of GSEA and GSVA. Finally, the ligand-receptor interactions such as vegfc-vegfr2, angptl1 were changes in CM.

CONCLUSIONS

The CM showed the significant heterogeneities in DM, which played an important role in myocardial fibrosis induce by hyperglycemia.

Targeting lymphatic function in cardiovascular-kidney-metabolic syndrome: preclinical methods to analyze lymphatic function and therapeutic opportunities

The lymphatic vascular system spans nearly every organ in the body and serves as an important network that maintains fluid, metabolite, and immune cell homeostasis. Recently, there has been a growing interest in the role of lymphatic biology in chronic disorders outside the realm of lymphatic abnormalities, lymphedema, or oncology, such as cardiovascular-kidney-metabolic syndrome (CKM). We propose that enhancing lymphatic function pharmacologically may be a novel and effective way to improve quality of life in patients with CKM syndrome by engaging multiple pathologies at once throughout the body. Several promising therapeutic targets that enhance lymphatic function have already been reported and may have clinical benefit. However, much remains unclear of the discreet ways the lymphatic vasculature interacts with CKM pathogenesis, and translation of these therapeutic targets to clinical development is challenging. Thus, the field must improve characterization of lymphatic function in preclinical mouse models of CKM syndrome to better understand molecular mechanisms of disease and uncover effective therapies.

Vitexin protects against high glucose-induced endothelial cell apoptosis and oxidative stress via Wnt/β-catenin and Nrf2 signalling pathway

Vitexin, a polyphenolic flavonoid, has been reported to be traditionally applied in the treatment of diabetes, cancer and cardiovascular diseases.

OBJECTIVE

The aim of this study was to investigate the anti-apoptosis and anti-oxidation effect and the potential mechanism of vitexin on high glucose-induced HUVECs.

MATERIALS AND METHODS

A high dose of glucose was added to HUVECs to establish an in vitro model. The cell viability was detected by CCK8 and flow cytometry assays. 2,7-dichlorodihydrofluorescein diacetate, colorimetry, and enzyme-linked immunosorbent assay were performed to detect oxidative stress. Besides, top flash and western blotting were employed to evaluate the effect of vitexin on Wnt/β-catenin. Furthermore, a Wnt/β-catenin inhibitor (KYA1797K) was used to confirm whether Wnt/β-catenin is involved in the protection of vitexin. At the same time, RT-PCR and western blot were performed to determine the effect of vitexin on Nrf2, while immunofluorescence assays were employed for the assessment of Nrf2 localisation. Then, in order to validate that Nrf2 plays an important role in the anti-oxidant effect of vitexin, methods were utilised to silence Nrf2 gene.

RESULTS

Herein, vitexin inhibited the proliferation and apoptosis of HG-mediated HUVECs. Mechanically, vitexin disrupted Wnt/β-catenin signalling pathway, thus resulting in the decrease of apoptosis in HG-induced HUVECs. A Wnt/β-catenin inhibitor (KYA1797K), was used for reverse verification. In the meantime, vitexin administration decreased reactive oxygen species (ROS) production and malondialdehyde (MDA) content and increased superoxide dismutase (SOD) activity in HG-induced HUVECs. Further investigations have revealed vitexin activated Nrf2 in HUVEC under high glucose, which was involved in its anti-oxidant effects.

CONCLUSION

Our investigation demonstrated that vitexin protected HUVECs from high glucose-induced injury via up-regulation of Wnt/β-catenin and Nrf2 signalling pathway. These results suggested that vitexin might serve as a potential drug for atherosclerosis and cardiovascular complications of diabetes.

Preliminary report of a thoracic duct-to-pulmonary vein lymphovenous anastomosis in swine: A novel technique and potential treatment for lymphatic failure

OBJECTIVE

The thoracic duct is the largest lymphatic vessel in the body, and carries fluid and nutrients absorbed in abdominal organs to the central venous circulation. Thoracic duct obstruction can cause significant failure of the lymphatic circulation (i.e., protein-losing enteropathy, plastic bronchitis, etc.). Surgical anastomosis between the thoracic duct and central venous circulation has been used to treat thoracic duct obstruction but cannot provide lymphatic decompression in patients with superior vena cava obstruction or chronically elevated central venous pressures (e.g., right heart failure, single ventricle physiology, etc.). Therefore, this preclinical feasibility study sought to develop a novel and optimal surgical technique for creating a thoracic duct-to-pulmonary vein lymphovenous anastomosis (LVA) in swine that could remain patent and preserve unidirectional lymphatic fluid flow into the systemic venous circulation to provide therapeutic decompression of the lymphatic circulation even at high central venous pressures.

METHODS

A thoracic duct-to-pulmonary vein LVA was attempted in 10 piglets (median age 80 [IQR 80-83] days; weight 22.5 [IQR 21.4-26.8] kg). After a right thoracotomy, the thoracic duct was mobilized, transected, and anastomosed to the right inferior pulmonary vein. Animals were systemically anticoagulated on post-operative day 1. Lymphangiography was used to evaluate LVA patency up to post-operative day 7.

RESULTS

A thoracic duct-to-pulmonary vein LVA was successfully completed in 8/10 (80.0%) piglets, of which 6/8 (75.0%) survived to the intended study endpoint without any complication (median 6 [IQR 4-7] days). Initially, 2/10 (20.0%) LVAs were aborted intraoperatively, and 2/10 (20.0%) animals were euthanized early due to post-operative complications. However, using an optimized surgical technique, the success rate for creating a thoracic duct-to-pulmonary vein LVA in six animals was 100%, all of which survived to their intended study endpoint without any complications (median 6 [IQR 4-7] days). LVAs remained patent for up to seven days.

CONCLUSION

A thoracic duct-to-pulmonary vein LVA can be completed safely and remain patent for at least one week with systemic anticoagulation, which provides an important proof-of-concept that this novel intervention could effectively offload the lymphatic circulation in patients with lymphatic failure and elevated central venous pressures.

Lymphatic failure and lymphatic interventions: Knowledge gaps and future directions for a new frontier in congenital heart disease

Lymphatic failure is a broad term that describes the lymphatic circulation's inability to adequately transport fluid and solutes out of the interstitium and into the systemic venous circulation, which can result in dysfunction and dysregulation of immune responses, dietary fat absorption, and fluid balance maintenance. Several investigations have recently elucidated the nexus between lymphatic failure and congenital heart disease, and the associated morbidity and mortality is now well-recognized. However, the precise pathophysiology and pathogenesis of lymphatic failure remains poorly understood and relatively understudied, and there are no targeted therapeutics or interventions to reliably prevent its development and progression. Thus, there is growing enthusiasm towards the development and application of novel percutaneous and surgical lymphatic interventions. Moreover, there is consensus that further investigations are needed to delineate the underlying mechanisms of lymphatic failure, which could help identify novel therapeutic targets and develop innovative procedures to improve the overall quality of life and survival of these patients. With these considerations, this review aims to provide an overview of the lymphatic circulation and its vasculature as it relates to current understandings into the pathophysiology and pathogenesis of lymphatic failure in patients with congenital heart disease, while also summarizing strategies for evaluating and managing lymphatic complications, as well as specific areas of interest for future translational and clinical research efforts.

Role of the Lymphatics in Cardiac Disease

Cardiovascular diseases remain the largest cause of death worldwide with recent evidence increasingly attributing the development and progression of these diseases to an exacerbated inflammatory response. As a result, significant research is now focused on modifying the immune environment to prevent the disease progression. This in turn has highlighted the lymphatic system in the pathophysiology of cardiovascular diseases owing, in part, to its established function in immune cell surveillance and trafficking. In this review, we highlight the role of the cardiac lymphatic system and its potential as an immunomodulatory therapeutic target in selected cardiovascular diseases.

Empagliflozin and liraglutide ameliorate HFpEF in mice via augmenting the Erbb4 signaling pathway

Heart failure with preserved ejection fraction (HFpEF) is closely associated with metabolic derangement. Sodium glucose cotransporter-2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP-1RA) exert anti-HFpEF effects, but the underlying mechanisms remain unclear. In this study, we explored the anti-HFpEF effects of empagliflozin and liraglutide and the underlying molecular mechanisms in a mouse model of HFpEF. This model was established by high-fat diet (HFD) feeding plus Nω-nitro-L-arginine methyl ester (L-NAME) treatment. The mice were treated with empagliflozin (20 mg·kg-1·d-1, i.g.) or liraglutide (0.3 mg·kg-1·d-1, i.p.) or their combination for 4 weeks. At the end of the experimental protocol, cardiac function was measured using ultrasound, then mice were euthanized and heart, liver, and kidney tissues were collected. Nuclei were isolated from frozen mouse ventricular tissue for single-nucleus RNA-sequencing (snRNA-seq). We showed that administration of empagliflozin or liraglutide alone or in combination significantly improved diastolic function, ameliorated cardiomyocyte hypertrophy and cardiac fibrosis, as well as exercise tolerance but no synergism was observed in the combination group. Furthermore, empagliflozin and/or liraglutide lowered body weight, improved glucose metabolism, lowered blood pressure, and improved liver and kidney function. After the withdrawal of empagliflozin or liraglutide for 1 week, these beneficial effects tended to diminish. The snRNA-seq analysis revealed a subcluster of myocytes, in which Erbb4 expression was down-regulated under HFpEF conditions, and restored by empagliflozin or liraglutide. Pseudo-time trajectory analysis and cell-to-cell communication studies confirmed that the Erbb4 pathway was a prominent pathway essential for both drug actions. In the HFpEF mouse model, both empagliflozin and liraglutide reversed Erbb4 down-regulation. In rat h9c2 cells, we showed that palmitic acid- or high glucose-induced changes in PKCα and/or ERK1/2 phosphorylation at least in part through Erbb4. Collectively, the single-cell atlas reveals the anti-HFpEF mechanism of empagliflozin and liraglutide, suggesting that Erbb4 pathway represents a new therapeutic target for HFpEF. Effects and mechanisms of action of empagliflozin and liraglutide in HFpEF mice. HFpEF was induced with a high-fat diet and L-NAME for 15 weeks, and treatment with empagliflozin and liraglutide improved the HFpEF phenotype. Single nucleus RNA sequencing (snRNA-seq) was used to reveal the underlying mechanism of action of empagliflozin and liraglutide.

Recent advances in mechanistic studies of heart failure with preserved ejection fraction and its comorbidities-Role of microRNAs

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) is a multifaceted syndrome with a complex aetiology commonly associated with comorbidities such as diabetes mellitus, obesity, hypertension and renal disease. Various diseases induce systemic, chronic and low-grade inflammation; microvascular dysfunction; metabolic stress; tissue ischemia; and fibrosis, leading to HFpEF. An effective treatment for HFpEF is lacking, largely owing to its pathophysiological heterogeneity. Recent studies have revealed that microRNAs (miRNAs) play crucial roles in regulating the pathogenesis of HFpEF and its comorbidities.

METHODS

This narrative review included original articles and reviews published over the past 20 years found through 'PubMed' and 'Web of Science'. The search terms included "HFpEF," "MicroRNAs," "comorbidities," "Microvascular Dysfunction (MVD)," "inflammation," "pathophysiology," "endothelial dysfunction," "energy metabolism abnormalities" "cardiac fibrosis" and "treatment."

RESULTS

Inflammation, MVD, abnormal energy metabolism, myocardial hypertrophy and myocardial fibrosis are important pathophysiological mechanisms underlying HFpEF. As gene expression regulators, miRNAs may contribute to the pathophysiology of HFpEF and are expected to serve in the stratification of patients with HFpEF and as prognostic indicators for monitoring treatment responses.

CONCLUSIONS

A customized strategy based on miRNAs has emerged as an effective treatment for HFpEF. In this review, we discuss recent research surrounding miRNAs and HFpEF and propose potential miRNA targets for the pathophysiology of HFpEF and its comorbidities. Although current research concerning miRNAs and their therapeutic potential is in its early stages, miRNA-based diagnostics and therapeutics hold great promise in the future.

Endothelial Senescence: From Macro- to Micro-Vasculature and Its Implications on Cardiovascular Health

Endothelial cells line at the most inner layer of blood vessels. They act to control hemostasis, arterial tone/reactivity, wound healing, tissue oxygen, and nutrient supply. With age, endothelial cells become senescent, characterized by reduced regeneration capacity, inflammation, and abnormal secretory profile. Endothelial senescence represents one of the earliest features of arterial ageing and contributes to many age-related diseases. Compared to those in arteries and veins, endothelial cells of the microcirculation exhibit a greater extent of heterogeneity. Microcirculatory endothelial senescence leads to a declined capillary density, reduced angiogenic potentials, decreased blood flow, impaired barrier properties, and hypoperfusion in a tissue or organ-dependent manner. The heterogeneous phenotypes of microvascular endothelial cells in a particular vascular bed and across different tissues remain largely unknown. Accordingly, the mechanisms underlying macro- and micro-vascular endothelial senescence vary in different pathophysiological conditions, thus offering specific target(s) for therapeutic development of senolytic drugs.

Non-coding RNAs in the pathophysiology of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is the largest unmet clinical need in cardiovascular medicine. Despite decades of research, the treatment option for HFpEF is still limited, indicating our ongoing incomplete understanding on the underlying molecular mechanisms. Non-coding RNAs, comprising of microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), are non-protein coding RNA transcripts, which are implicated in various cardiovascular diseases. However, their role in the pathogenesis of HFpEF is unknown. Here, we discuss the role of miRNAs, lncRNAs and circRNAs that are involved in the pathophysiology of HFpEF, namely microvascular dysfunction, inflammation, diastolic dysfunction and cardiac fibrosis. We interrogated clinical evidence and dissected the molecular mechanisms of the ncRNAs by looking at the relevant in vivo and in vitro models that mimic the co-morbidities in patients with HFpEF. Finally, we discuss the potential of ncRNAs as biomarkers and potential novel therapeutic targets for future HFpEF treatment.

Diabetic Cardiomyopathy: 2023 Update by the International Multidisciplinary Board of Experts

Diabetes mellitus (DM) is considered by many the pandemic of the 21st century and is associated with multiple organ damages. Among these, cardiovascular complications are responsible for an incredible burden of mortality and morbidity in Western Countries. The study of the pathological mechanisms responsible for the cardiovascular complications in DM patients is key for the development of new therapeutic strategies. The metabolic disorders caused by hyperglycemia, insulin resistance, and dyslipidemia, results in a cascade of pathomorphological changes favoring the atherosclerotic process and leading to myocardial remodeling. Parallel to this, oxidative stress, calcium overload, mitochondrial dysfunction, activation of protein kinase C signaling pathways, myocardial lipomatosis, and low-grade inflammation of the myocardium - are the main pathways responsible for the diabetic cardiomyopathy development. This review aims to appraise and discuss the pathogenetic mechanisms behind the diabetic cardiomyopathy development.

Endothelial Dysfunction and Heart Failure with Preserved Ejection Fraction-An Updated Review of the Literature

Heart failure (HF) is a clinical syndrome consisting of typical symptoms and signs due to structural and/or functional abnormalities of the heart, resulting in elevated intracardiac pressures and/or inadequate cardiac output. The vascular system plays a crucial role in the development and progression of HF regardless of ejection fraction, with endothelial dysfunction (ED) as one of the principal features of HF. The main ED manifestations (i.e., impaired endothelium-dependent vasodilation, increased oxidative stress, chronic inflammation, leukocyte adhesion, and endothelial cell senescence) affect the systemic and pulmonary haemodynamic and the renal and coronary circulation. The present review is aimed to discuss the contribution of ED to HF pathophysiology-in particular, HF with preserved ejection fraction-ED role in HF patients, and the possible effects of pharmacological and non-pharmacological approaches. For this purpose, relevant data from a literature search (PubMed, Scopus, EMBASE, and Medline) were reviewed. As a result, ED, assessed via venous occlusion plethysmography or flow-mediated dilation, was shown to be independently associated with poor outcomes in HF patients (e.g., mortality, cardiovascular events, and hospitalization due to worsening HF). In addition, SGLT2 inhibitors, endothelin antagonists, endothelial nitric oxide synthase cofactors, antioxidants, and exercise training were shown to positively modulate ED in HF. Despite the need for future research to better clarify the role of the vascular endothelium in HF, ED represents an interesting and promising potential therapeutic target.

Role of Lymphangiogenesis in Cardiac Repair and Regeneration

This article highlights the importance of the structure and function of cardiac lymphatics in cardiovascular diseases and the therapeutic potential of cardiac lymphangiogenesis. Specifically, we explore the innate lymphangiogenic response to damaged cardiac tissue or cardiac injury, derive key findings from regenerative models demonstrating how robust lymphangiogenic responses can be supported to improve cardiac function, and introduce an approach to imaging the structure and function of cardiac lymphatics.

Deletion of Endothelial TRPV4 Protects Heart From Pressure Overload-Induced Hypertrophy

BACKGROUND

Left ventricular hypertrophy is a bipolar response, starting as an adaptive response to the hemodynamic challenge, but over time develops maladaptive pathology partly due to microvascular rarefaction and impaired coronary angiogenesis. Despite the profound influence on cardiac function, the mechanotransduction mechanisms that regulate coronary angiogenesis, leading to heart failure, are not well known.

METHODS

We subjected endothelial-specific knockout mice of mechanically activated ion channel, TRPV4 (transient receptor potential cation channel subfamily V member 4; TRPV4ECKO) to pressure overload via transverse aortic constriction and examined cardiac function, cardiomyocyte hypertrophy, cardiac fibrosis, and apoptosis. Further, we measured microvascular density and underlying TRPV4 mechanotransduction mechanisms using human microvascular endothelial cells, extracellular matrix gels of varying stiffness, unbiased RNA sequencing, small interfering RNA, Western blot, quantitative-PCR, and confocal immunofluorescence techniques.

RESULTS

We demonstrate that endothelial-specific deletion of TRPV4 preserved cardiac function, cardiomyocyte structure, and reduced cardiac fibrosis compared with TRPV4lox/lox mice, 28 days post-transverse aortic constriction. Interestingly, comprehensive RNA sequencing analysis revealed an upregulation of proangiogenic factors (VEGFα [vascular endothelial growth factor α], NOS3 [nitric oxide synthase 3], and FGF2 [fibroblast growth factor 2]) with concomitant increase in microvascular density in TRPV4ECKO hearts after transverse aortic constriction compared with TRPV4lox/lox. Further, an increased expression of VEGFR2 (vascular endothelial growth factor receptor 2) and activation of the YAP (yes-associated protein) pathway were observed in TRPV4ECKO hearts. Mechanistically, we found that downregulation of TRPV4 in endothelial cells induced matrix stiffness-dependent activation of YAP and VEGFR2 via the Rho/Rho kinase/large tumor suppressor kinase pathway.

CONCLUSIONS

Our results suggest that endothelial TRPV4 acts as a mechanical break for coronary angiogenesis, and uncoupling endothelial TRPV4 mechanotransduction attenuates pathological cardiac hypertrophy by enhancing coronary angiogenesis.

The importance of microvascular inflammation in ageing and age-related diseases: a position paper from the ESH working group on small arteries, section of microvascular inflammation

Microcirculation is pervasive and orchestrates a profound regulatory cross-talk with the surrounding tissue and organs. Similarly, it is one of the earliest biological systems targeted by environmental stressors and consequently involved in the development and progression of ageing and age-related disease. Microvascular dysfunction, if not targeted, leads to a steady derangement of the phenotype, which cumulates comorbidities and eventually results in a nonrescuable, very high-cardiovascular risk. Along the broad spectrum of pathologies, both shared and distinct molecular pathways and pathophysiological alteration are involved in the disruption of microvascular homeostasis, all pointing to microvascular inflammation as the putative primary culprit. This position paper explores the presence and the detrimental contribution of microvascular inflammation across the whole spectrum of chronic age-related diseases, which characterise the 21st-century healthcare landscape. The manuscript aims to strongly affirm the centrality of microvascular inflammation by recapitulating the current evidence and providing a clear synoptic view of the whole cardiometabolic derangement. Indeed, there is an urgent need for further mechanistic exploration to identify clear, very early or disease-specific molecular targets to provide an effective therapeutic strategy against the otherwise unstoppable rising prevalence of age-related diseases.

Diminished vasculogenesis under inflammatory conditions is mediated by Activin A

Severe inflammatory stress often leads to vessel rarefaction and fibrosis, resulting in limited tissue recovery. However, signaling pathways mediating these processes are not completely understood. Patients with ischemic and inflammatory conditions have increased systemic Activin A level, which frequently correlates with the severity of pathology. Yet, Activin A's contribution to disease progression, specifically to vascular homeostasis and remodeling, is not well defined. This study investigated vasculogenesis in an inflammatory environment with an emphasis on Activin A's role. Exposure of endothelial cells (EC) and perivascular cells (adipose stromal cells, ASC) to inflammatory stimuli (represented by blood mononuclear cells from healthy donors activated with lipopolysaccharide, aPBMC) dramatically decreased EC tubulogenesis or caused vessel rarefaction compared to control co-cultures, concurrent with increased Activin A secretion. Both EC and ASC upregulated Inhibin Ba mRNA and Activin A secretion in response to aPBMC or their secretome. We identified TNFα (in EC) and IL-1β (in EC and ASC) as the exclusive inflammatory factors, present in aPBMC secretome, responsible for induction of Activin A. Similar to ASC, brain and placental pericytes upregulated Activin A in response to aPBMC and IL-1β, but not TNFα. Both these cytokines individually diminished EC tubulogenesis. Blocking Activin A with neutralizing IgG mitigated detrimental effects of aPBMC or TNFα/IL-1β on tubulogenesis in vitro and vessel formation in vivo. This study delineates the signaling pathway through which inflammatory cells have a detrimental effect on vessel formation and homeostasis, and highlights the central role of Activin A in this process. Transitory interference with Activin A during early phases of inflammatory or ischemic insult, with neutralizing antibodies or scavengers, may benefit vasculature preservation and overall tissue recovery.

Three-vessel coronary infusion of cardiosphere-derived cells for the treatment of heart failure with preserved ejection fraction in a pre-clinical pig model

Heart failure with preserved ejection fraction (HFpEF) is a major public health concern. Its outcome is poor and, as of today, barely any treatments have been able to decrease its morbidity or mortality. Cardiosphere-derived cells (CDCs) are heart cell products with anti-fibrotic, anti-inflammatory and angiogenic properties. Here, we tested the efficacy of CDCs in improving left ventricular (LV) structure and function in pigs with HFpEF. Fourteen chronically instrumented pigs received continuous angiotensin II infusion for 5 weeks. LV function was investigated through hemodynamic measurements and echocardiography at baseline, after 3 weeks of angiotensin II infusion before three-vessel intra-coronary CDC (n = 6) or placebo (n = 8) administration and 2 weeks after treatment (i.e., at completion of the protocol). As expected, arterial pressure was significantly and similarly increased in both groups. This was accompanied by LV hypertrophy that was not affected by CDCs. LV systolic function remained similarly preserved during the whole protocol in both groups. In contrast, LV diastolic function was impaired (increases in Tau, LV end-diastolic pressure as well as E/A, E/E'septal and E/E'lateral ratios) but CDC treatment significantly improved all of these parameters. The beneficial effect of CDCs on LV diastolic function was not explained by reduced LV hypertrophy or increased arteriolar density; however, interstitial fibrosis was markedly reduced. Three-vessel intra-coronary administration of CDCs improves LV diastolic function and reduces LV fibrosis in this hypertensive model of HFpEF.

Accelerated ageing and coronary microvascular dysfunction in chronic heart failure in Tgαq*44 mice

Age represents a major risk factor in heart failure (HF). However, the mechanisms linking ageing and HF are not clear. We aimed to identify the functional, morphological and transcriptomic changes that could be attributed to cardiac ageing in a model of slowly progressing HF in Tgαq*44 mice in reference to the cardiac ageing process in FVB mice. In FVB mice, ageing resulted in the impairment of diastolic cardiac function and in basal coronary flow (CF), perivascular and interstitial fibrosis without changes in the cardiac activity of angiotensin-converting enzyme (ACE) or aldosterone plasma concentration. In Tgαq*44 mice, HF progression was featured by the impairment of systolic and diastolic cardiac function and in basal CF that was associated with a distinct rearrangement of the capillary architecture, pronounced perivascular and interstitial fibrosis, progressive activation of cardiac ACE and systemic angiotensin-aldosterone-dependent pathways. Interestingly, cardiac ageing genes and processes were represented in Tgαq*44 mice not only in late but also in early phases of HF, as evidenced by cardiac transcriptome analysis. Thirty-four genes and 8 biological processes, identified as being ageing related, occurred early and persisted along HF progression in Tgαq*44 mice and were mostly associated with extracellular matrix remodelling and fibrosis compatible with perivascular fibrosis resulting in coronary microvascular dysfunction (CMD) in Tgαq*44 mice. In conclusion, accelerated and persistent cardiac ageing contributes to the pathophysiology of chronic HF in Tgαq*44 mice. In particular, prominent perivascular fibrosis of microcirculation resulting in CMD represents an accelerated cardiac ageing phenotype that requires targeted treatment in chronic HF.

New insights into the molecular mechanisms of SGLT2 inhibitors on ventricular remodeling

Ventricular remodeling is a pathological process of ventricular response to continuous stimuli such as pressure overload, ischemia or ischemia-reperfusion, which can lead to the change of cardiac structure and function structure, which is central to the pathophysiology of heart failure (HF) and is an established prognostic factor in patients with HF. Sodium glucose cotransporter 2 inhibitors (SGLT2i) get a new hypoglycemic drug that inhibit sodium glucose coconspirator on renal tubular epithelial cells. Recently, clinical trials increasingly and animal experiments increasingly have shown that SGLT2 inhibitors have been largely applied in the fields of cardiovascular diseases, forinstance heart failure, myocardial ischemia-reperfusion injury, myocardial infarction, atrial fibrillation, metabolic diseases such as obesity, diabetes cardiomyopathy and other diseases play a cardiovascular protective role in addition to hypoglycemic. These diseases are association with ventricular remodeling. Inhibiting ventricular remodeling can improve the readmission rate and mortality of patients with heart failure. So far, clinical trials and animal experiments demonstrate that the protective effect of SGLT2 inhibitors in the cardiovascular field is bound to inhibit ventricular remodeling. Therefore, this review briefly investigates the molecular mechanisms of SGLT2 inhibitors on ameliorating ventricular remodeling, and further explore the mechanisms of cardiovascular protection of SGLT2 inhibitors, in order to establish strategies for ventricular remodeling to prevent the progress of heart failure.

Levosimendan Reverses Cardiac Malfunction and Cardiomyocyte Ferroptosis During Heart Failure with Preserved Ejection Fraction via Connexin 43 Signaling Activation

PURPOSE

In recent decades, the occurrence of heart failure with preserved ejection fraction (HFpEF) has outweighed that of heart failure with reduced ejection fraction by degrees, but few drugs have been demonstrated to improve long-term clinical outcomes in patients with HFpEF. Levosimendan, a calcium-sensitizing cardiotonic agent, improves decompensated heart failure clinically. However, the anti-HFpEF activities of levosimendan and underlying molecular mechanisms are unclear.

METHODS

In this study, a double-hit HFpEF C57BL/6N mouse model was established, and levosimendan (3 mg/kg/week) was administered to HFpEF mice aged 13 to 17 weeks. Different biological experimental techniques were used to verify the protective effects of levosimendan against HFpEF.

RESULTS

After four weeks of drug treatment, left ventricular diastolic dysfunction, cardiac hypertrophy, pulmonary congestion, and exercise exhaustion were significantly alleviated. Junction proteins in the endothelial barrier and between cardiomyocytes were also improved by levosimendan. Among the gap junction channel proteins, connexin 43, which was especially highly expressed in cardiomyocytes, mediated mitochondrial protection. Furthermore, levosimendan reversed mitochondrial malfunction in HFpEF mice, as evidenced by increased mitofilin and decreased ROS, superoxide anion, NOX4, and cytochrome C levels. Interestingly, after levosimendan administration, myocardial tissue from HFpEF mice showed restricted ferroptosis, indicated by an increased GSH/GSSG ratio; upregulated GPX4, xCT, and FSP-1 expression; and reduced intracellular ferrous ion, MDA, and 4-HNE levels.

CONCLUSION

Regular long-term levosimendan administration can benefit cardiac function in a mouse model of HFpEF with metabolic syndromes (namely, obesity and hypertension) by activating connexin 43-mediated mitochondrial protection and sequential ferroptosis inhibition in cardiomyocytes.

Myocardial fat accumulation is associated with cardiac dysfunction in patients with type 2 diabetes, especially in elderly or female patients: a retrospective observational study

BACKGROUND

Ectopic fat is fat that accumulates in or around specific organs or compartments of the body including myocardium. The clinical features of type 2 diabetes patients with high fat accumulation in the myocardium remain unknown. Moreover, little is known about the influence of myocardial fat accumulation in type 2 diabetes on coronary artery disease and cardiac dysfunction. We aimed to clarify the clinical features, including cardiac functions, of type 2 diabetes patients with myocardial fat accumulation.

METHODS

We retrospectively enrolled type 2 diabetes patients who underwent ECG-gated coronary computed tomography angiography (CCTA) and abdominal computed tomography (CT) scan examinations within 1 year of CCTA from January 2000 to March 2021. High fat accumulation in the myocardium was defined as the low mean myocardial CT value of three regions of interest, and the associations between CT values and clinical characteristics or cardiac functions were assessed.

RESULTS

In total, 124 patients were enrolled (72 males and 52 females). The mean age was 66.6 years, the mean BMI was 26.2 kg/m², the mean ejection fraction (EF) was 67.6%, and the mean myocardial CT value was 47.7 Hounsfield unit. A significant positive correlation was found between myocardial CT value and EF (r = 0.3644, p = 0.0004). The multiple regression analyses also showed that myocardial CT value was independently associated with EF (estimate, 0.304; 95% confidence interval (CI) 0.092 to 0.517; p = 0.0056). Myocardial CT value showed significant negative correlations with BMI, visceral fat area and subcutaneous fat area (r = - 0.1923, - 0.2654, and -0.3569, respectively, p < 0.05). In patients who were ≥ 65 years or female, myocardial CT value showed significant positive correlations with not only EF (r = 0.3542 and 0.4085, respectively, p < 0.01) but also early lateral annular tissue Doppler velocity (Lat e') (r = 0.5148 and 0.5361, respectively, p < 0.05). The multiple regression analyses showed that myocardial CT value was independently associated with EF and Lat e' in these subgroups (p < 0.05).

CONCLUSIONS

Patients with type 2 diabetes, especially in elderly or female patients, who had more myocardial fat had more severe left ventricular systolic and diastolic dysfunctions. Reducing myocardial fat accumulation may be a therapeutic target for type 2 diabetes patients.

Mice with endothelial cell-selective adhesion molecule deficiency develop coronary microvascular rarefaction and left ventricle diastolic dysfunction

Endothelial cell-selective adhesion molecule (ESAM) regulates inflammatory cell adhesion and transmigration and promotes angiogenesis. Here, we examined the role of ESAM in cardiac vascularization, inflammatory cell infiltration, and left ventricle (LV) diastolic function under basal and hemodynamic stress conditions. We employed mice with homozygous genetic deletion of ESAM (ESAM-/- ) and also performed uninephrectomy and aldosterone infusion (UNX-Aldo) to induce volume and pressure overload. Using echocardiography, we found that ESAM-/- mice display no change in systolic function. However, they develop LV diastolic dysfunction, as indicated by a significantly reduced E/A ratio (E = early, A = late mitral inflow peak velocities), increased E/e' ratio, isovolumic relaxation time (IVRT), and E wave deceleration time. An unbiased automated tracing and 3D reconstruction of coronary vasculature revealed that ESAM-/- mice had reduced coronary vascular density. Arteries of ESAM-/- mice exhibited impaired endothelial sprouting and in cultured endothelial cells siRNA-mediated ESAM knockdown reduced tube formation. Changes in ESAM-/- mice were accompanied by elevated myocardial inflammatory cytokine and myeloperoxidase-positive neutrophil levels. Furthermore, UNX-Aldo procedure in wild type mice induced LV diastolic dysfunction, which was accompanied by significantly increased serum ESAM levels. When compared to wild types, ESAM-/- mice with UNX-Aldo displayed worsening of LV diastolic function, as indicated by increased IVRT and pulmonary edema. Thus, we propose that ESAM plays a mechanistic role in proper myocardial vascularization and the maintenance of LV diastolic function under basal and hemodynamic stress conditions.

Combination Sodium Nitrite and Hydralazine Therapy Attenuates Heart Failure With Preserved Ejection Fraction Severity in a "2-Hit" Murine Model

Background Recent studies have suggested that cardiac nitrosative stress mediated by pathological overproduction of nitric oxide (NO) via inducible NO synthase (iNOS) contributes to the pathogenesis of heart failure with preserved ejection fraction (HFpEF). Other studies have suggested that endothelial NO synthase (eNOS) dysfunction and attenuated NO bioavailability contribute to HFpEF morbidity and mortality. We sought to further investigate dysregulated NO signaling and to examine the effects of a NO-based dual therapy (sodium nitrite+hydralazine) following the onset of HFpEF using a "2-hit" murine model. Methods and Results Nine-week-old male C57BL/6 N mice (n=15 per group) were treated concurrently with high-fat diet and N(ω)-nitro-L-arginine methyl ester (L-NAME) (0.5 g/L per day) via drinking water for 10 weeks. At week 5, mice were randomized into either vehicle (normal saline) or combination treatment with sodium nitrite (75 mg/L in the drinking water) and hydralazine (2.0 mg/kg IP, BID). Cardiac structure and function were monitored with echocardiography and invasive hemodynamic measurements. Cardiac mitochondrial respiration, aortic vascular function, and exercise performance were also evaluated. Circulating and myocardial nitrite were measured to determine the bioavailability of NO. Circulating markers of oxidative or nitrosative stress as well as systemic inflammation were also determined. Severe HFpEF was evident by significantly elevated E/E', LVEDP, and Tau in mice treated with L-NAME and HFD, which was associated with impaired NO bioavailability, mitochondrial respiration, aortic vascular function, and exercise capacity. Treatment with sodium nitrite and hydralazine restored NO bioavailability, reduced oxidative and nitrosative stress, preserved endothelial function and mitochondrial respiration, limited the fibrotic response, and improved exercise capacity, ultimately attenuating the severity of "two-hit" HFpEF. Conclusions Our data demonstrate that nitrite, a well-established biomarker of NO bioavailability and a physiological source of NO, is significantly reduced in the heart and circulation in the "2-hit" mouse HFpEF model. Furthermore, sodium nitrite+hydralazine combined therapy significantly attenuated the severity of HFpEF in the "2-hit" cardiometabolic HFpEF. These data suggest that supplementing NO-based therapeutics with a potent antioxidant and vasodilator agent may result in synergistic benefits for the treatment of HFpEF.

Association of circulating MtDNA with CVD in hemodialysis patients and in vitro effect of exogenous MtDNA on cardiac microvascular inflammation

BACKGROUND

Chronic kidney disease (CKD) patients sustain a fairly high prevalence of cardiovascular disease (CVD). Microvascular inflammation is an early manifestation of CVD, and the released mitochondrial DNA (MtDNA) has been proposed to be a crucial integrator of inflammatory signals. Herein, the aim of this study was to determine the relationship between CVD, microvessel, and circulating MtDNA in the settings of uremia.

METHODS

Forty-two maintenance hemodialysis (MHD) patients and 36 health controls were enrolled in this study. Plasma cell-free MtDNA was detected by TaqMan-based qPCR assay. CVD risk markers including high-sensitive C-reactive protein (Hs-CRP), monocyte chemoattractant protein-1 (MCP-1), fibrinogen, and erythrocyte sedimentation rate (ESR) were measured by standard assays. Ten-year CVD risk was calculated from the Framingham risk score (FRS) model. In vitro study, human cardiac microvascular endothelial cells (HCMECs) were incubated with normal or uremic serum, with or without exogenous MtDNA. Intracellular toll-like receptor 9 (TLR9), adhesion molecule 1 (ICAM-1), MCP-1 and tumor necrosis factor-α (TNF-α) and cytosolic MtDNA were detected by qPCR.

RESULTS

Plasma MtDNA in MHD patients was significantly higher than healthy controls (4.74 vs. 2.41 × 10⁵ copies/mL; p = 0.000). Subsequently, the MHD patients were classified into two groups based on the MtDNA median (4.34 × 10⁵ copies/mL). In stratified analyses, the levels of Hs-CRP (5.02 vs. 3.73 mg/L; p = 0.042) and MCP-l (99.97 vs. 64.72 pg/mL; p = 0.008) and FRS (21.80 vs. 16.52; p = 0.016) in the high plasma MtDNA group were higher than those in the low plasma MtDNA group. In vitro study, we found that exogenous MtDNA aggravated uremic serum-induced microvascular inflammation (ICAM-1 and TNF-α) in HCMECs (all p < 0.05). Besides, the addition of MtDNA to the medium resulted in a further increase in cytosolic MtDNA and TLR9 levels in uremic serum-treated cells (all p < 0.05). In patients with MHD, MtDNA levels in plasma were significantly reduced after a single routine hemodialysis (pre 4.47 vs. post 3.45 × 10⁵ copies/mL; p = 0.001) or hemodiafiltration (pre 4.85 vs. post 4.09 × 10⁵ copies/mL; p = 0.001). These two approaches seem similar in terms of MtDNA clearance rate (21.26% vs. 11.94%; p = 0.172).

CONCLUSIONS

Overall, the present study suggests that MtDNA released into the circulation under the uremic toxin environment may adversely affect the cardiovascular system by exacerbating microvascular inflammation, and that reducing circulating MtDNA might be a future therapeutic strategy for the prevention of MHD-related CVD.

Shenlian extract decreases mitochondrial autophagy to regulate mitochondrial function in microvascular to alleviate coronary artery no-reflow

Shenlian (SL) extract has been proven to be effective in the prevention and treatment of atherosclerosis and myocardial ischemia. However, the function and molecular mechanisms of SL on coronary artery no-reflow have not been fully elucidated. This study was designed to investigate the contribution of SL extract in repressing excessive mitochondrial autophagy to protect the mitochondrial function and prevent coronary artery no-reflow. The improvement of SL on coronary artery no-reflow was observed in vivo experiments and the molecular mechanisms were further explored through vitro experiments. First, a coronary artery no-reflow rat model was built by ligating the left anterior descending coronary artery for 2 hr of ischemia, followed by 24 hr of reperfusion. Thioflavin S (6%, 1 ml/kg) was injected into the inferior vena cava to mark the no-reflow area. Transmission electron microscopy was performed to observe the cellular structure, mitochondrial structure, and mitochondrial autophagy of the endothelial cells. Immunofluorescence was used to observe the microvascular barrier function and microvascular inflammation. Cardiac microvascular endothelial cells (CMECs) were isolated from rats. The CMECs were deprived of oxygen-glucose deprivation (OGD) for 2 hr and reoxygenated for 4 hr to mimic the Myocardial ischemia-reperfusion (MI/R) injury-induced coronary artery no-reflow in vitro. Mitochondrial membrane potential was assessed using JC-1 dye. Intracellular adenosine triphosphate (ATP) levels were determined using an ATP assay kit. The cell total reactive oxygen species (ROS) levels and cell apoptosis rate were analyzed by flow cytometry. Colocalization of mitochondria and lysosomes indirectly indicated mitophagy. The representative ultrastructural morphologies of the autophagosomes and autolysosomes were also observed under transmission electron microscopy. The mitochondrial autophagy-related proteins (LC3II/I, P62, PINK, and Parkin) were analyzed using Western blot analysis. In vivo, results showed that, compared with the model group, SL could reduce the no-reflow area from 37.04 ± 9.67% to 18.31 ± 4.01% (1.08 g·kg^-1 SL), 13.79 ± 4.77% (2.16 g·kg^-1 SL), and 12.67 ± 2.47% (4.32 g·kg^-1 SL). The extract also significantly increased the left ventricular ejection fraction (EF) and left ventricular fractional shortening (FS) (p < 0.05 or p < 0.01). The fluorescence intensities of VE-cadherin, which is a junctional protein that preserves the microvascular barrier function, decreased to ~74.05% of the baseline levels in the no-reflow rats and increased to 89.87%(1.08 g·kg^-1 SL), 82.23% (2.16 g·kg^-1 SL), and 89.69% (4.32 g·kg^-1 SL) of the baseline levels by SL treatment. SL administration repressed the neutrophil migration into the myocardium. The oxygen-glucose deprivation/reoxygenation (OGD/R) model was induced in vitro to mimic microvascular ischemia-reperfusion injury. The impaired mitochondrial function after OGD/R injury led to decreased ATP production, calcium overload, the excessive opening of the Mitochondrial Permeability Transition Pore, decreased mitochondrial membrane potential, and reduced ROS scavenging ability (p < 0.05 or p < 0.01). The normal autophagosomes (double-membrane vacuoles with autophagic content) in the sham group were rarely found. The large morphology and autophagosomes were frequently observed in the model group. By contrast, SL inhibited the excessive activation of mitochondrial autophagy. The mitochondrial autophagy regulated by the PINK/Parkin pathway was excessively activated. However, administration of SL prevented the activation of the PINK/Parkin pathway and inhibited excessive mitochondrial autophagy to regulate mitochondrial dysfunction. Results also demonstrated that mitochondrial dysfunction stimulated endothelial cell barrier dysfunction, but Evans blue transmission was significantly decreased and transmembrane resistance was increased significantly by SL treatment (p < 0.05 or p < 0.01). Carbonylcyanide-3-chlorophenylhydrazone (CCCP) could activate the PINK/Parkin pathway. CCCP reversed the regulation of SL on mitochondrial autophagy and mitochondrial function. SL could alleviate coronary artery no-reflow by protecting the microvasculature by regulating mitochondrial function. The underlying mechanism was related to decreased mitochondrial autophagy by the PINK/Parkin pathway.

Inflammatory pathways in heart failure with preserved left ventricular ejection fraction: implications for future interventions

Many patients with symptoms and signs of heart failure have a left ventricular ejection fraction ≥50%, termed heart failure with preserved ejection fraction (HFpEF). HFpEF is a heterogeneous syndrome mainly affecting older people who have many other cardiac and non-cardiac conditions that often cast doubt on the origin of symptoms, such as breathlessness, or signs, such as peripheral oedema, rendering them neither sensitive nor specific to the diagnosis of HFpEF. Currently, management of HFpEF is mainly directed at controlling symptoms and treating comorbid conditions such as hypertension, atrial fibrillation, anaemia, and coronary artery disease. HFpEF is also characterized by a persistent increase in inflammatory biomarkers. Inflammation may be a key driver of the development and progression of HFpEF and many of its associated comorbidities. Detailed characterization of specific inflammatory pathways may provide insights into the pathophysiology of HFpEF and guide its future management. There is growing interest in novel therapies specifically designed to target deregulated inflammation in many therapeutic areas, including cardiovascular disease. However, large-scale clinical trials investigating the effectiveness of anti-inflammatory treatments in HFpEF are still lacking. In this manuscript, we review the role of inflammation in HFpEF and the possible implications for future trials.

Progress on the role of traditional Chinese medicine in therapeutic angiogenesis of heart failure

ETHNOPHARMACOLOGICAL RELEVANCE

Cardiovascular diseases are still the leading cause of death worldwide. Heart failure (HF), as the terminal stage of many cardiovascular diseases, has brought a heavy burden to the global medical system. Microvascular rarefaction (decreased myocardial capillary density) with reduced coronary flow reserve is a hallmark of HF and therapeutic myocardial angiogenesis is now emerging as a promising approach for the prevention and treatment in HF. Traditional Chinese medicine (TCM) has made remarkable achievements in the treatment of many cardiovascular diseases. Growing evidence have shown that their protective effect in HF is closely related to therapeutic angiogenesis.

AIM OF THE STUDY

This review is to enlighten the therapeutic effect and pro-angiogenic mechanism of TCM in HF, and provide valuable hints for the development of pro-angiogenic drugs for the treatment of HF.

MATERIALS AND METHODS

The relevant information about cardioprotective TCM was collected from electronic scientific databases such as PubMed, Web of Science, ScienceDirect, and China National Knowledge Infrastructure (CNKI).

RESULTS

The studies showed that TCM formulas, extracts, and compounds from herbal medicines can provide therapeutic effect in HF with their pro-angiogenic activity. Their actions are achieved mainly by regulating the key angiogenesis factors particularly VEGF, as well as related regulators including signal molecules and pathways, non-coding miRNAs and stem cells.

CONCLUSION

TCM and their active components might be promising in therapeutic angiogenesis for the treatment of HF.

Benefits of the Non-Steroidal Mineralocorticoid Receptor Antagonist Finerenone in Metabolic Syndrome-Related Heart Failure with Preserved Ejection Fraction

The mineralocorticoid receptor (MR) plays an important role in the development of chronic kidney disease (CKD) and associated cardiovascular complications. Antagonizing the overactivation of the MR with MR antagonists (MRA) is a therapeutic option, but their use in patients with CKD is limited due to the associated risk of hyperkalemia. Finerenone is a non-steroidal MRA associated with an improved benefit-risk profile in comparison to steroidal MRAs. In this study, we decided to test whether finerenone improves renal and cardiac function in male hypertensive and diabetic ZSF1 rats as an established preclinical HFpEF model. Finerenone was administered at 10 mg/kg/day for 12 weeks. Cardiac function/hemodynamics were assessed in vivo. ZSF1 rats showed classical signs of CKD with increased BUN, UACR, hypertrophy, and fibrosis of the kidney together with characteristic signs of HFpEF including cardiac fibrosis, diastolic dysfunction, and decreased cardiac perfusion. Finerenone treatment did not impact kidney function but reduced renal hypertrophy and cardiac fibrosis. Interestingly, finerenone ameliorated diastolic dysfunction and cardiac perfusion in ZSF1 rats. In summary, we show for the first time that non-steroidal MR antagonism by finerenone attenuates cardiac diastolic dysfunction and improves cardiac perfusion in a preclinical HFpEF model. These cardiac benefits were found to be largely independent of renal benefits.

Empagliflozin inhibits coronary microvascular dysfunction and reduces cardiac pericyte loss in db/db mice

Background

Coronary microvascular dysfunction (CMD) is a pathophysiological feature of diabetic heart disease. However, whether sodium-glucose cotransporter 2 (SGLT2) inhibitors protect the cardiovascular system by alleviating CMD is not known.

Objective

We observed the protective effects of empagliflozin (EMPA) on diabetic CMD.

Materials and methods

The mice were randomly divided into a db/db group and a db/db + EMPA group, and db/m mice served as controls. At 8 weeks of age, the db/db + EMPA group was given empagliflozin 10 mg/(kg⋅d) by gavage for 8 weeks. Body weight, fasting blood glucose and blood pressure were dynamically observed. Cardiac systolic and diastolic function and coronary flow reserve (CFR) were detected using echocardiography. The coronary microvascular structure and distribution of cardiac pericytes were observed using immunofluorescence staining. Picrosirius red staining was performed to evaluate cardiac fibrosis.

Results

Empagliflozin lowered the increased fasting blood glucose levels of the db/db group. The left ventricular ejection fraction, left ventricular fractional shortening, E/A ratio and E/e' ratio were not significantly different between the three groups. CFR was decreased in the db/db group, but EMPA significantly improved CFR. In contrast to the sparse and abnormal expansion of coronary microvessels observed in the db/db group, the number of coronary microvessels was increased, and the capillary diameter was decreased in the db/db + EMPA group. The number and microvascular coverage of cardiac pericytes were reduced in the db/db mice but were improved by EMPA. The cardiac fibrosis was increased in db/db group and may alleviate by EMPA.

Conclusion

Empagliflozin inhibited CMD and reduced cardiac pericyte loss in diabetic mice.

Inflamed adipose tissue: A culprit underlying obesity and heart failure with preserved ejection fraction

The incidence of heart failure with preserved ejection fraction is increasing in patients with obesity, diabetes, hypertension, and in the aging population. However, there is a lack of adequate clinical treatment. Patients with obesity-related heart failure with preserved ejection fraction display unique pathophysiological and phenotypic characteristics, suggesting that obesity could be one of its specific phenotypes. There has been an increasing recognition that overnutrition in obesity causes adipose tissue expansion and local and systemic inflammation, which consequently exacerbates cardiac remodeling and leads to the development of obese heart failure with preserved ejection fraction. Furthermore, overnutrition leads to cellular metabolic reprogramming and activates inflammatory signaling cascades in various cardiac cells, thereby promoting maladaptive cardiac remodeling. Growing evidence indicates that the innate immune response pathway from the NLRP3 inflammasome, to interleukin-1 to interleukin-6, is involved in the generation of obesity-related systemic inflammation and heart failure with preserved ejection fraction. This review established the existence of obese heart failure with preserved ejection fraction based on structural and functional changes, elaborated the inflammation mechanisms of obese heart failure with preserved ejection fraction, proposed that NLRP3 inflammasome activation may play an important role in adiposity-induced inflammation, and summarized the potential therapeutic approaches.

Cell therapy attenuates endothelial dysfunction in hypertensive rats with heart failure and preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is defined by increased left ventricular (LV) stiffness, impaired vascular compliance, and fibrosis. Although systemic inflammation, driven by comorbidities, has been proposed to play a key role, the precise pathogenesis remains elusive. To test the hypothesis that inflammation drives endothelial dysfunction in HFpEF, we used cardiosphere-derived cells (CDCs), which reduce inflammation and fibrosis, improving function, structure, and survival in HFpEF rats. Dahl salt-sensitive rats fed a high-salt diet developed HFpEF, as manifested by diastolic dysfunction, systemic inflammation, and accelerated mortality. Rats were randomly allocated to receive intracoronary infusion of CDCs or vehicle. Two weeks later, inflammation, oxidative stress, and endothelial function were analyzed. Single-cell RNA sequencing of heart tissue was used to assay transcriptomic changes. CDCs improved endothelial-dependent vasodilation while reducing oxidative stress and restoring endothelial nitric oxide synthase (eNOS) expression. RNA sequencing revealed CDC-induced attenuation of pathways underlying endothelial cell leukocyte binding and innate immunity. Exposure of endothelial cells to CDC-secreted extracellular vesicles in vitro reduced VCAM-1 protein expression and attenuated monocyte adhesion and transmigration. Cell therapy with CDCs corrects diastolic dysfunction, reduces oxidative stress, and restores vascular reactivity. These findings lend credence to the hypothesis that inflammatory changes of the vascular endothelium are important, if not central, to HFpEF pathogenesis.NEW & NOTEWORTHY We tested the concept that inflammation of endothelial cells is a major pathogenic factor in HFpEF. CDCs are heart-derived cell products with verified anti-inflammatory therapeutic properties. Infusion of CDCs reduced oxidative stress, restored eNOS abundance, lowered monocyte levels, and rescued the expression of multiple disease-associated genes, thereby restoring vascular reactivity. The salutary effects of CDCs support the hypothesis that inflammation of endothelial cells is a proximate driver of HFpEF.

Heart Failure with Preserved Ejection Fraction: Pathogenesis, Diagnosis, Exercise, and Medical Therapies

Heart failure with preserved ejection fraction (HFpEF) accounts for more than one-half of total heart failure cases, with a high prevalence and poor prognosis, especially in older and female patients. Patients with HFpEF are characterized by hypertension, left ventricular hypertrophy, and diastolic dysfunction, and the main symptoms are dyspnea and exercise intolerance. HFpEF is currently poorly studied, and pharmacological treatment for HFpEF is still underexplored. Accumulating clinical trials have shown that exercise could exert benefits on diastolic dysfunction and quality of life in patients with HFpEF. However, there is a high limitation for applying exercise therapy due to exercise intolerance in patients with HFpEF. Key effectors of exercise-protection could be novel therapeutic targets for developing drugs to prevent and treat HFpEF. In this review article, we provide an overview of the pathogenic factors, diagnostic methods, research animal models, the mechanisms of exercise-mediated cardiac protection, and current treatments for HFpEF.

The Mutual Relationship among Cardiovascular Diseases and COVID-19: Focus on Micronutrients Imbalance

Micronutrients are ions and vitamins humbly required by the human body. They play a main role in several physiological mechanisms and their imbalance is strongly associated with potentially-fatal complications. Micronutrient imbalance is associated with many cardiovascular diseases, such as arrythmias, heart failure, and ischemic heart disease. It has been also observed in coronavirus disease 2019 (COVID-19), particularly in most severe patients. The relationship between cardiovascular diseases and COVID-19 is mutual: the latter triggers cardiovascular disease onset and worsening while patients with previous cardiovascular disease may develop a more severe form of COVID-19. In addition to the well-known pathophysiological mechanisms binding COVID-19 and cardiovascular diseases together, increasing importance is being given to the impact of micronutrient alterations, often present during COVID-19 and able to affect the balance responsible for a good functioning of the cardiovascular system. In particular, hypokalemia, hypomagnesemia, hyponatremia, and hypocalcemia are strongly associated with worse outcome, while vitamin A and D deficiency are associated with thromboembolic events in COVID-19. Thus, considering how frequent the cardiovascular involvement is in patients with COVID-19, and how it majorly affects their prognosis, this manuscript provides a comprehensive review on the role of micronutrient imbalance in the interconnection between COVID-19 and cardiovascular diseases.

Aldehyde dehydrogenase 2 augments adiponectin signaling in coronary angiogenesis in HFpEF associated with diabetes

4-hydroxy-2-nonenal (4HNE), an oxidative stress byproduct, is elevated in diabetes which decreases coronary angiogenesis, and this was rescued by the 4HNE detoxifying enzyme, aldehyde dehydrogenase 2 (ALDH2). Adiponectin (APN), an adipocytokine, has pro-angiogenic properties and its loss of function is critical in diabetes and its complications. Coronary endothelial cell (CEC) damage is the initiating step of diabetes-mediated heart failure with preserved ejection fraction (HFpEF) pathogenesis. Thus, we hypothesize that ALDH2 restores 4HNE-induced downregulation of APN signaling in CECs and subsequent coronary angiogenesis in diabetic HFpEF. Treatment with disulfiram, an ALDH2 inhibitor, exacerbated 4HNE-mediated decreases in APN-induced increased coronary angiogenesis and APN-signaling cascades, whereas pretreatment with alda1, an ALDH2 activator, rescued the effect of 4HNE. We employed control mice (db/m), spontaneous type-2 diabetic mice (db/db), ALDH2*2 knock-in mutant mice with intrinsic low ALDH2 activity (AL), and diabetic mice with intrinsic low ALDH2 activity (AF) mice that were created by crossing db/db and AL mice to test our hypothesis in vivo. AF mice exhibited heart failure with preserved ejection fraction (HFpEF)/severe diastolic dysfunction at 6 months with a preserved systolic function compared with db/db mice as well as 3 months of their age. Decreased APN-mediated coronary angiogenesis, along with increased circulatory APN levels and decreased cardiac APN signaling (index of APN resistance) were higher in AF mice relative to db/db mice. Alda1 treatment improved APN-mediated angiogenesis in AF and db/db mice. In summary, 4HNE-induces APN resistance and a subsequent decrease in coronary angiogenesis in diabetic mouse heart which was rescued by ALDH2.

The relationship between ambulatory arterial stiffness index and left ventricular diastolic dysfunction in HFpEF: a prospective observational study

Background

The relationship between ambulatory arterial stiffness index (AASI) and left ventricular diastolic dysfunction (LVDD) in patients with heart failure with preserved ejection fraction (HFpEF) is unknown. We aimed to investigate the association between the AASI and LVDD in HFpEF.

Methods

We prospective enrolled consecutive patients with HFpEF in Chongqing, China. Twenty-four-hour ambulatory blood pressure monitoring (24 h-ABPM) and echocardiography were performed in each patient. AASI was obtained through individual 24 h-ABPM. The relationship between AASI and LVDD was analyzed.

Results

A total of 107 patients with HFpEF were included. The mean age was 68.45 ± 14.02 years and 63 (59%) were women. The patients were divided into two groups according to the upper normal border of AASI (0.55). AASI > 0.55 group were more likely to be older, to have higher mean systolic blood pressure and worsen left ventricular diastolic function than AASI group ≤ 0.55. AASI was closely positive related to the diastolic function parameters, including mean E/e′ (r = 0.307, P = 0.001), septal E/e′ (r = 0.290, P = 0.002), lateral E/e′ (r = 0.276, P = 0.004) and E (r = 0.274, P = 0.004). After adjusting for conventional risk factors, AASI was still an independent risk factors of mean E/e′ > 10 in patients with HFpEF (OR: 2.929, 95%CI: 1.214–7.064, P = 0.017), and the association between AASI and mean E/e′ > 14 was reduced (OR: 2.457, 95%CI: 1.030–5.860, P = 0.043). AASI had a partial predictive value for mean E/e′ > 10 (AUC = 0.691, P = 0.002), while the predictive value for mean E/e′ > 14 was attenuated (AUC = 0.624, P = 0.034).

Conclusion

AASI was positive related to E/e′ in HFpEF and might be an independent risk factor for the increase of mean E/e′.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02679-6.

Association of body mass index and prognosis in patients with HFpEF: A dose-response meta-analysis

BACKGROUND

Although agreements regarding the negative effects of obesity on the development of heart failure with preserved ejection fraction (HFpEF) have been reached, the relationship between body mass index (BMI) and adverse outcomes in HFpEF patients are still debatable. Therefore, we conducted the dose-response meta-analysis to investigate this relationship.

METHODS

We searched the PubMed and Embase databases up to February 2022 for studies that evaluated the association between BMI and prognostic outcomes in patients with HFpEF. A cubic spline random-effects model was used to fit the potential dose-response curve. The effect estimates were expressed as adjusted hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

A total of 11 studies involving 69,273 patients with HFpEF were included. The summary HR for all-cause mortality was 0.90 (95% CI, 0.84-0.95) per 5 units increase in BMI, but the association was U-shaped (P_nonlinear < 0.01) with the nadir of risk at a BMI of 32-34 kg/m². The summary HR for HF hospitalization was 1.12 (95% CI, 1.05-1.19) with a significant positive linear association (P_nonlinear = 0.54).

CONCLUSIONS

For patients with HFpEF, there was a positive linear association of BMI with HF hospitalization, while a U-shaped relationship between BMI and all-cause mortality was observed with the lowest event rate at a BMI of 32-34 kg/m².

Physical Exercise Modalities for the Management of Heart Failure With Preserved Ejection Fraction: A Systematic Review and Meta-Analysis

ABSTRACT

Different physical exercise modalities have been widely studied in patients having heart failure with preserved ejection fraction (HFpEF) but with variably reported findings. We, therefore, conducted a systematic review and meta-analysis to evaluate whether the efficacy of physical activity in the management of HFpEF is related to exercise modalities. PubMed and Embase were searched up to July 2021. The eligible studies included randomized controlled trials that identified effects of physical exercise on patients with HFpEF. Sixteen studies were included to evaluate the efficiency of physical exercise in HFpEF. A pooled analysis showed that exercise training significantly improved peak oxygen uptake (VO2), ventilatory anaerobic threshold, distance covered in the 6-minute walking test, the ratio of early diastolic mitral inflow to annular velocities, the Short Form 36 physical component score, and the Minnesota Living with Heart Failure Questionnaire total score. However, the changes in other echocardiographic parameters including the ratio of peak early to late diastolic mitral inflow velocities, early diastolic mitral annular velocity, and left atrial volume index were not significant. Both high-intensity and moderate-intensity training significantly improved exercise capacity (as defined by peak VO2), with moderate-intensity exercise having a superior effect. Furthermore, exercise-induced improvement in peak VO2 was partially correlated with exercise duration. Physical exercise could substantially improve exercise capacity, quality of life, and some indicators of cardiac diastolic function in patients with HFpEF. A protocol of moderate-intensity exercise training lasting a longer duration might be more beneficial compared with high-intensity training for patients with HFpEF.

Molecular mechanisms of coronary microvascular endothelial dysfunction in diabetes mellitus: focus on mitochondrial quality surveillance

Coronary microvascular endothelial dysfunction is both a culprit and a victim of diabetes, and can accelerate diabetes-related microvascular and macrovascular complications by promoting vasoconstrictive, pro-inflammatory and pro-thrombotic responses. Perturbed mitochondrial function induces oxidative stress, disrupts metabolism and activates apoptosis in endothelial cells, thus exacerbating the progression of coronary microvascular complications in diabetes. The mitochondrial quality surveillance (MQS) system responds to stress by altering mitochondrial metabolism, dynamics (fission and fusion), mitophagy and biogenesis. Dysfunctional mitochondria are prone to fission, which generates two distinct types of mitochondria: one with a normal and the other with a depolarized mitochondrial membrane potential. Mitochondrial fusion and mitophagy can restore the membrane potential and homeostasis of defective mitochondrial fragments. Mitophagy-induced decreases in the mitochondrial population can be reversed by mitochondrial biogenesis. MQS abnormalities induce pathological mitochondrial fission, delayed mitophagy, impaired metabolism and defective biogenesis, thus promoting the accumulation of unhealthy mitochondria and the activation of mitochondria-dependent apoptosis. In this review, we examine the effects of MQS on mitochondrial fitness and explore the association of MQS disorders with coronary microvascular endothelial dysfunction in diabetes. We also discuss the potential to treat diabetes-related coronary microvascular endothelial dysfunction using novel MQS-altering drugs.

The Cardiomyocyte in Heart Failure with Preserved Ejection Fraction—Victim of Its Environment?

Heart failure (HF) with preserved left ventricular ejection fraction (HFpEF) is becoming the predominant form of HF. However, medical therapy that improves cardiovascular outcome in HF patients with almost normal and normal systolic left ventricular function, but diastolic dysfunction is missing. The cause of this unmet need is incomplete understanding of HFpEF pathophysiology, the heterogeneity of the patient population, and poor matching of therapeutic mechanisms and primary pathophysiological processes. Recently, animal models improved understanding of the pathophysiological role of highly prevalent and often concomitantly presenting comorbidity in HFpEF patients. Evidence from these animal models provide first insight into cellular pathophysiology not considered so far in HFpEF disease, promising that improved understanding may provide new therapeutical targets. This review merges observation from animal models and human HFpEF disease with the intention to converge cardiomyocytes pathophysiological aspects and clinical knowledge.

Cardiac lymphatics: state of the art

PURPOSE OF REVIEW

The beneficial role of cardiac lymphatics in health and disease has begun to be recognized, with both preclinical and clinical evidence demonstrating that lymphangiogenesis is activated in cardiovascular diseases. This review aims to summarize our current understanding of the regulation and impact of cardiac lymphatic remodeling during development and in adult life, highlighting emerging concepts regarding distinguishing traits of cardiac lymphatic endothelial cells (LEC).

RECENT FINDINGS

Genetic lineage-tracing and clonal analyses have revealed that a proportion of cardiac LECs originate from nonvenous sources. Further, these sources may vary between different regions of the heart, and could translate to differences in LEC sensitivity to molecular regulators. Several therapeutic approaches have been applied to investigate how lymphatics contribute to resolution of myocardial edema and inflammation in cardiovascular diseases. From these studies have emerged novel insights, notably concerning the cross-talk between lymphatics and cardiac interstitial cells, especially immune cells.

SUMMARY

Recent years have witnessed a significant expansion in our knowledge of the molecular characteristics and regulation of cardiac lymphatics. The current body of work is in support of critical contributions of cardiac lymphatics to maintain both fluid and immune homeostasis in the heart.

Evaluating the adverse outcome of subtypes of heart failure with preserved ejection fraction defined by machine learning: A systematic review focused on defining high risk phenogroups

The ability to distinguish clinically meaningful subtypes of heart failure with preserved ejection fraction (HFpEF) has recently been examined by machine learning techniques but studies appear to have produced discordant results. The objective of this study is to synthesize the types of HFpEF by examining their features and relating them to phenotypes with adverse prognosis. A systematic search was conducted using the search terms "Diastolic Heart Failure" OR "heart failure with preserved ejection fraction" OR "heart failure with normal ejection fraction" OR "HFpEF" AND "machine learning" OR "artificial intelligence" OR 'computational biology'. Ten studies were identified and they varied in their prevalence of ten clinical variables: age, sex, body mass index (BMI) or obesity, hypertension, diabetes mellitus, coronary artery disease, atrial fibrillation, chronic kidney disease, chronic obstructive pulmonary disease or symptom severity (NYHA class or BNP). The clinical findings associated with the different phenotypes in > 85 % of studies were age, hypertension, atrial fibrillation, chronic kidney disease and worse symptoms severity; an adverse outcome was in 65 % to 85 % of studies identified diabetes mellitus and female sex and in less than 65 % of studies was body mass index or obesity, and coronary artery disease. COPD was a relevant factor in only 33 % of studies. Adverse clinical outcome - death or admission to hospital (for heart failure) defined phenogroups with the worst outcome. Combining the 4 studies that calculated the MAGGIC score showed a significant (p<0.05) linear relationship between MAGGIC score and outcome, using the one-year event rate. A new score based on strength of the evidence of the HFpEF studies analyzed here, using 9 variables (eliminating COPD), showed a significant (p<0.009) linear relationship with one-year event rate. Three studies examined biomarkers in detail and the ones most prominently related to outcome or consistently found in the studies were GDF15, FABP4, FGF23, sST2, renin and TNF. The dominant factors that identified phenotypes of HFpEF with adverse outcome were hypertension, atrial fibrillation, chronic kidney disease and worse symptoms severity. A new simplified score, based on clinical factors, was proposed to assess prognosis in HFpEF. Several biomarkers were consistently elevated in phenogroups with adverse outcomes and may indicate the underlying mechanism or pathophysiology specific for phenotypes with an adverse prognosis.

Myocardial oedema: pathophysiological basis and implications for the failing heart

Myocardial fluid homeostasis relies on a complex interplay between microvascular filtration, interstitial hydration, cardiomyocyte water uptake and lymphatic removal. Dysregulation of one or more of these mechanisms may result in myocardial oedema. Interstitial and intracellular fluid accumulation disrupts myocardial architecture, intercellular communication, and metabolic pathways, decreasing contractility and increasing myocardial stiffness. The widespread use of cardiac magnetic resonance enabled the identification of myocardial oedema as a clinically relevant imaging finding with prognostic implications in several types of heart failure. Furthermore, growing experimental evidence has contributed to a better understanding of the physical and molecular interactions in the microvascular barrier, myocardial interstitium and lymphatics and how they might be disrupted in heart failure. In this review, we summarize current knowledge on the factors controlling myocardial water balance in the healthy and failing heart and pinpoint the new potential therapeutic avenues.

Mitophagy alleviates ischemia/reperfusion-induced microvascular damage through improving mitochondrial quality control

The coronary arteries mainly function to perfuse the myocardium. When coronary artery resistance increases, myocardial perfusion decreases and myocardial remodeling occurs. Mitochondrial damage has been regarded as the primary cause of microvascular dysfunction. In the present study, we explored the effects of mitophagy activation on microvascular damage. Hypoxia/reoxygenation injury induced mitochondrial oxidative stress, thereby promoting mitochondrial dysfunction in endothelial cells. Mitochondrial impairment induced apoptosis, reducing the viability and proliferation of endothelial cells. However, supplementation with the mitophagy inducer urolithin A (UA) preserved mitochondrial function by reducing mitochondrial oxidative stress and stabilizing the mitochondrial membrane potential in endothelial cells. UA also sustained the viability and improved the proliferative capacity of endothelial cells by suppressing apoptotic factors and upregulating cyclins D and E. In addition, UA inhibited mitochondrial fission and restored mitochondrial fusion, which reduced the proportion of fragmented mitochondria within endothelial cells. UA enhanced mitochondrial biogenesis in endothelial cells by upregulating sirtuin 3 and peroxisome proliferator-activated receptor gamma coactivator 1-alpha. These results suggested that activation of mitophagy may reduce hypoxia/reoxygenation-induced cardiac microvascular damage by improving mitochondrial quality control and increasing cell viability and proliferation.

TMEM60 Promotes the Proliferation and Migration and Inhibits the Apoptosis of Glioma through Modulating AKT Signaling

Glioma is a highly fatal malignancy with aggressive proliferation, migration, and invasion metastasis due to aberrant genetic regulation. This work aimed to determine the function of transmembrane protein 60 (TMEM60) during glioma development. The level of TMEM60 in glioma tissues and normal tissues and its correlation with glioma prognosis were checked in The Cancer Genome Atlas (TCGA) database. The levels of TMEM60 in glioma cell lines and normal astrocytes were determined by quantitative real-time PCR and western blotting assay. TMEM60 knockdown and overexpression were conducted, followed by detection of cell viability, migration, invasion, and apoptosis. CCK-8 and colony formation assay were adopted to detect cell viability proliferation. Transwell assay was performed to measure cell migration and invasion. Cell apoptosis was evaluated by flow cytometry. The alternation of key proteins in the PI3K/Akt signaling pathway was measured by western blotting. TMEM60 expression was significantly higher in glioma tissues than that in the healthy control and was correlated with poor overall survival of patients. The protein and mRNA levels of TMEM60 were both elevated in glioma cell lines in comparison with the normal cell lines. Elevated level of TMEM60 led to enhanced proliferation, migration, and invasion and suppressed cell apoptosis. TMEM60 promoted the activation of PI3K/Akt signaling. Our data suggested that TMEM60 plays an oncogenic role in glioma progression via activating the PI3K/Akt signaling pathway.

Endothelial Dysfunction and Diabetic Cardiomyopathy

The cardiovascular complications contribute to a majority of diabetes associated morbidity and mortality, accounting for 44% of death in those patients with type 1 diabetes mellitus (DM) and 52% of deaths in type 2 DM. Diabetes elicits cardiovascular dysfunction through 2 major mechanisms: ischemic and non-ischemic. Non-ischemic injury is usually under-recognized although common in DM patients, and also a pathogenic factor of heart failure in those diabetic individuals complicated with ischemic heart disease. Diabetic cardiomyopathy (DCM) is defined as a heart disease in which the myocardium is structurally and functionally abnormal in the absence of coronary artery disease, hypertensive, valvular, or congenital heart disorders in diabetic patients, theoretically caused by non-ischemic injury solely. Current therapeutic strategies targeting DCM mainly address the increased blood glucose levels, however, the effects on heart function are disappointed. Accumulating data indicate endothelial dysfunction plays a critical role in the initiation and development of DCM. Hyperglycemia, hyperinsulinemia, and insulin resistance cause the damages of endothelial function, including barrier dysfunction, impaired nitric oxide (NO) activity, excessive reactive oxygen species (ROS) production, oxidative stress, and inflammatory dysregulation. In turn, endothelial dysfunction promotes impaired myocardial metabolism, intracellular Ca²⁺ mishandling, endoplasmic reticulum (ER) stress, mitochondrial defect, accumulation of advanced glycation end products, and extracellular matrix (ECM) deposit, leads to cardiac stiffness, fibrosis, and remodeling, eventually results in cardiac diastolic dysfunction, systolic dysfunction, and heart failure. While endothelial dysfunction is closely related to cardiac dysfunction and heart failure seen in DCM, clinical strategies for restoring endothelial function are still missing. This review summarizes the timely findings related to the effects of endothelial dysfunction on the disorder of myocardium as well as cardiac function, provides mechanical insights in pathogenesis and pathophysiology of DCM developing, and highlights potential therapeutic targets.

Microvascular Ageing Links Metabolic Disease to Age-Related Disorders: The Role of Oxidative Stress and Inflammation in Promoting Microvascular Dysfunction

ABSTRACT

Longer life span and increased prevalence of chronic, noncommunicable, inflammatory diseases fuel cardiovascular mortality. The microcirculation is central in the cross talk between ageing, inflammation, cardiovascular, and metabolic diseases. Microvascular dysfunction, characterized by alteration in the microvascular endothelial function and wall structure, is described in an increasing number of chronic age-associated diseases, suggesting that it might be a marker of ageing superior to chronological age. The aim of this review is to thoroughly explore the connections between microvascular dysfunction, ageing, and metabolic disorders by detailing the major role played by inflammation and oxidative stress in their evolution. Older age, hypertension, nutrient abundance, and hyperglycemia concur in the induction of a persistent low-grade inflammatory response, defined as meta-inflammation or inflammageing. This increases the local generation of reactive oxygen species that further impairs endothelial function and amplifies the local inflammatory response. Mitochondrial dysfunction is a hallmark of many age-related diseases. The alterations of mitochondrial function promote irreversible modification in microvascular structure. The interest in the hypothesis of chronic inflammation at the center of the ageing process lies in its therapeutic implications. Inhibition of specific inflammatory pathways has been shown to lower the risk of many age-related diseases, including cardiovascular disease. However, the whole architecture of the inflammatory response underpinning the ageing process and its impact on the burden of age-related diseases remain to be fully elucidated. Additional studies are needed to unravel the connection between these biological pathways and to address their therapeutic power in terms of cardiovascular prevention.