Rosuvastatin-attenuated heart failure in aged spontaneously hypertensive rats via PKCα/β2 signal pathway

The role of cardiomyocyte senescence in cardiovascular diseases: A molecular biology update

Cardiovascular diseases (CVD) are the leading cause of death worldwide, and advanced age is a main contributor to the prevalence of CVD. Cellular senescence is an irreversible state of cell cycle arrest that occurs in old age or after cells encounter various stresses. Senescent cells not only result in the reduction of cellular function, but also produce senescence-associated secretory phenotype (SASP) to affect surrounding cells and tissue microenvironment. There is increasing evidence that the gradual accumulation of senescent cardiomyocytes is causally involved in the decline of cardiovascular system function. To highlight the role of senescent cardiomyocytes in the pathophysiology of age-related CVD, we first introduced that senescent cardiomyoyctes can be identified by structural changes and several senescence-associated biomarkers. We subsequently provided a comprehensive summary of existing knowledge, outlining the compelling evidence on the relationship between senescent cardiomyocytes and age-related CVD phenotypes. In addition, we discussed that the significant therapeutic potential represented by the prevention of accelerated senescent cardiomyocytes, and the current status of some existing geroprotectors in the prevention and treatment of age-related CVD. Together, the review summarized the role of cardiomyocyte senescence in CVD, and explored the molecular knowledge of senescent cardiomyocytes and their potential clinical significance in developing senescent-based therapies, thereby providing important insights into their biology and potential therapeutic exploration.

Searching for Effective Treatments in HFpEF: Implications for Modeling the Disease in Rodents

BACKGROUND

While the prevalence of heart failure with preserved ejection fraction (HFpEF) has increased over the last two decades, there still remains a lack of effective treatment. A key therapeutic challenge is posed by the absence of animal models that accurately replicate the complexities of HFpEF. The present review summarizes the effects of a wide spectrum of therapeutic agents on HF.

METHODS

Two online databases were searched for studies; in total, 194 experimental protocols were analyzed following the PRISMA protocol.

RESULTS

A diverse range of models has been proposed for studying therapeutic interventions for HFpEF, with most being based on pressure overload and systemic hypertension. They have been used to evaluate more than 150 different substances including ARNIs, ARBs, HMGR inhibitors, SGLT-2 inhibitors and incretins. Existing preclinical studies have primarily focused on LV diastolic performance, and this has been significantly improved by a wide spectrum of candidate therapeutic agents. Few experiments have investigated the normalization of pulmonary congestion, exercise capacity, animal mortality, or certain molecular hallmarks of heart disease.

CONCLUSIONS

The development of comprehensive preclinical HFpEF models, with multi-organ system phenotyping and physiologic stress-based functional testing, is needed for more successful translation of preclinical research to clinical trials.

The effect of statins on RyR and RyR-associated disease

We sought to review the effects of statins on the ryanodine receptor (RyR) and on RyR-associated diseases, with an emphasis on catecholaminergic polymorphic ventricular tachycardia (CPVT). Statins can affect skeletal muscle and produce statin-associated muscle symptoms (SAMS) but have no adverse effects on cardiac muscle. These contrasting effects may be due to differences in how statins affect the skeletal (RyR1) and cardiac (RyR2) RyR. We searched PubMed to identify English language articles reporting the pathophysiology of the RyR, the effect of statins on RyR function, and on RyR-associated genetic diseases. We selected 150 articles for abstract review, 96 of which provided sufficient information to be included and were reviewed in detail. Fifteen articles highlighted the interaction of statins with the RyR. Nine identified the interaction of statins with RyR1, six addressed the interaction of statins with RyR2, 13 suggested that statins reduce ventricular arrhythmias (VA), and seven suggested that statins increase the risk of malignant hyperthermia (MH). In general, statins increase RyR1 and decrease RyR2 activity. We identified no articles examining the effect of statins on CPVT, a condition often caused by defects in RyR2. Statins appear to increase the risk of MH and decrease the risk of ventricular arrhythmia. The effect of statins on CPVT has not been directly examined, but statins' reduction in RyR2 function and their apparent reduction in VA suggest that they may be beneficial in this condition.

Rosuvastatin Reverses Hypertension-Induced Changes in the Aorta Structure and Endothelium-Dependent Relaxation in Rats Through Suppression of Apoptosis and Inflammation

Vascular remodeling is one of the most critical complications caused by hypertension. Previous studies have demonstrated that rosuvastatin has anti-inflammatory, antioxidant, and antiplatelet effects and therefore can be used to treat cardiovascular disease. In this study, we explored the beneficial effects of rosuvastatin in reversing aortic remodeling in spontaneously hypertensive rats. After treating with different doses of rosuvastatin, its antilipid, antiapoptosis, and anti-inflammatory effects were determined. We also examined whether rosuvastatin can improve the structure and function of the aorta. We found that rosuvastatin treatment of spontaneously hypertensive rats for 2 months at 2 different doses can effectively reduce the media thickness of the aorta compared with the control group. Similarly, rosuvastatin improved the vascular relaxation function of the aortic rings at a high level of acetylcholine in vitro. Mechanistically, it was found that rosuvastatin increased the expression of endothelial nitric oxide synthase and plasma nitrite/nitrate levels. Besides, rosuvastatin suppressed the apoptosis and inflammation and upregulated the expression of gap-junction complex connexin 43 both in media and endothelium. Finally, rosuvastatin inhibited the AT₁R/PKCα/HSP70 signaling transduction pathway. In summary, these findings demonstrated that rosuvastatin could improve the vascular structure and function mainly by increasing endothelial nitric oxide synthase expression and preventing apoptosis and inflammation. This study provided evidence that rosuvastatin has beneficial effects in reversing the remodeling of the aorta due to hypertension.

Activation of Liver X Receptors by GW3965 Attenuated Deoxycorticosterone Acetate-Salt Hypertension-Induced Cardiac Functional and Structural Changes

In this study, the effect of liver X receptor (LXR) activation on hypertension-induced cardiac structural and functional alterations was investigated. Hypertension was induced by deoxycorticosterone acetate (DOCA)-salt administration in uninephrectomized rats for 6 weeks. LXR agonist GW3965 (3-{3-[(2-chloro-3-trifluoromethyl-benzyl)-(2,2-diphenyl-ethyl)-amino]-propoxy}-phenyl)-acetic acid was given for the past week. Rhythmic activity and contractions of the isolated heart tissues were recorded. Biochemical parameters were assessed in ventricular tissue and plasma samples. Cardiac expressions of various proteins were examined, and histopathological evaluation was performed in the left ventricle and liver. GW3965 reduced systolic blood pressure and enhanced noradrenaline-stimulated papillary muscle contraction induced by DOCA-salt + uninephrectomy. Plasma and tissue total antioxidant capacity (TAC) increased and tissue 4-hydroxynonenal (4-HNE) levels decreased in the DOCA-salt group. GW3965 elevated plasma and tissue TAC levels in both of groups. Glucose-regulated protein-78 (GRP78), phospho-dsRNA-activated-protein kinase-like ER kinase (p-PERK), matrix metalloproteinase-2 (MMP-2), and nuclear factor-κB p65 (NF-κB p65) expression was augmented, and inhibitor-κB-α (IκB-α) expression was reduced in hypertensive hearts. The altered levels of all these markers were reversed by GW3965. Also, GW3965 ameliorated DOCA-salt + uninephrectomy-induced cardiac and hepatic inflammation and fibrosis. However, GW3965 unchanged the plasma lipid levels and hepatic balloon degeneration score. These results demonstrated that LXR activation may improve hypertension-induced cardiac changes without undesired effects.

Pravastatin alleviates intracellular calcium dysregulation induced by Interleukin-6 via the mitochondrial ROS pathway in adult ventricular myocytes

Acute inflammation often contributes to the increased arrhythmogenesis in the cardiomyocytes. We investigated the protective effects of pravastatin on calcium disorders induced by acute administration of pro-inflammatory cytokines in isolated ventricular myocytes and its underlying mechanisms. Wild-type mice were intraperitoneally injected for five days with either pravastatin 20 mg/kg per day or an equal volume of normal saline. Cytosol Ca²⁺ handling was studied in freshly isolated ventricular myocytes after acute exposure of interleukin-6 (IL-6) (1 ng/ml) for 120 min by Ionoptix and confocal microscopy. Acute administration of clinically relevant concentrations of IL-6 disturbed calcium handling in ventricular myocytes, which presented as decreased amplitudes, prolonged decay times of Ca²⁺ transients, and reduced sarcoplasmic reticulum (SR) calcium stores. The frequency of spontaneous Ca²⁺ release, including calcium sparks and spontaneous calcium waves, was dramatically enhanced in the setting of IL-6. Notably, the pretreatment of pravastatin alleviated disturbed Ca²⁺ cycling, reduced spontaneous Ca²⁺ leakage induced by IL-6. Mitochondrial ROS pathway may constitute the underlying mechanism of the protective effects of pravastatin. Pravastatin protected the cardiomyocytes against calcium disorders induced by IL-6 via the mitochondrial ROS pathway, which suggests that pravastatin may represent a promising auxiliary therapeutic strategy for cardiac injury under acute inflammation.

Therapeutic Potential of Oxytocin in Atherosclerotic Cardiovascular Disease: Mechanisms and Signaling Pathways

Coronary artery disease (CAD) is a major cardiovascular disease responsible for high morbidity and mortality worldwide. The major pathophysiological basis of CAD is atherosclerosis in association with varieties of immunometabolic disorders that can suppress oxytocin (OT) receptor (OTR) signaling in the cardiovascular system (CVS). By contrast, OT not only maintains cardiovascular integrity but also has the potential to suppress and even reverse atherosclerotic alterations and CAD. These protective effects of OT are associated with its protection of the heart and blood vessels from immunometabolic injuries and the resultant inflammation and apoptosis through both peripheral and central approaches. As a result, OT can decelerate the progression of atherosclerosis and facilitate the recovery of CVS from these injuries. At the cellular level, the protective effect of OT on CVS involves a broad array of OTR signaling events. These signals mainly belong to the reperfusion injury salvage kinase pathway that is composed of phosphatidylinositol 3-kinase-Akt-endothelial nitric oxide synthase cascades and extracellular signal-regulated protein kinase 1/2. Additionally, AMP-activated protein kinase, Ca²⁺/calmodulin-dependent protein kinase signaling and many others are also implicated in OTR signaling in the CVS protection. These signaling events interact coordinately at many levels to suppress the production of inflammatory cytokines and the activation of apoptotic pathways. A particular target of these signaling events is endoplasmic reticulum (ER) stress and mitochondrial oxidative stress that interact through mitochondria-associated ER membrane. In contrast to these protective effects and machineries, rare but serious cardiovascular disturbances were also reported in labor induction and animal studies including hypotension, reflexive tachycardia, coronary spasm or thrombosis and allergy. Here, we review our current understanding of the protective effect of OT against varieties of atherosclerotic etiologies as well as the approaches and underlying mechanisms of these effects. Moreover, potential cardiovascular disturbances following OT application are also discussed to avoid unwanted effects in clinical trials of OT usages.

Inhibition of SRC/FAK cue: A novel pathway for the synergistic effect of rosuvastatin on the anti-cancer effect of dasatinib in hepatocellular carcinoma

PURPOSE

Statins extended their hypocholestremic effect to show a promising anticancer activity. Hepatocellular carcinoma (HCC), the third common cause of cancer-related death, responded positively to statins. Some in-vitro studies reveal the rosuvastatin antitumor effect, but barely in-vivo studies. Hence, we evaluated the antitumor potential of rosuvastatin in a HCC model, the possible signaling cues involved, and whether it augments the dasatinib anticancer effect.

METHOD

For the in-vitro study, the IC₅₀ and the combination (CI)/dose reduction (DRI) indices were determined for HCC cell line (HepG2) treated with dasatinib and/or rosuvastatin. For the in-vivo study, mice with diethylnitrosamine-induced HCC were treated for 21 days with dasatinib and/or rosuvastatin (10 and 20 mg/kg, respectively). The p-focal adhesion kinase/p-rous sarcoma oncogene cellular homolog (p-FAK/p-Src) cascade and its downstream molecules were assessed.

RESULTS

The in-vitro study confirmed the synergistic effect of rosuvastatin with dasatinib, which entailed the in-vivo results. The two drugs decreased the p-FAK/p-Src cue along with p-Ras/c-Raf, p-STAT-3, and p-Akt levels to enhance apoptosis by an increase in caspase-3 level and a decline in survivin level. Additionally, they inhibited HGF, VEGF, and the MMP-9. Moreover, the different treatments downregulated the expression of proliferative cell nuclear antigen (PCNA) and Ki-67. The best effect was mediated by the combination regimen that surpassed the effect of either drug alone.

CONCLUSION

Our results highlighted some of the signals involved in rosuvastatin antitumor effect and nominate it as an adds-on therapy with dasatinib to yield a better effect in HCC through inhibiting the FAK/Src cascade.

Review of novel therapeutic targets for improving heart failure treatment based on experimental and clinical studies

Heart failure (HF) is a major public health priority due to its epidemiological transition and the world's aging population. HF is typified by continuous loss of contractile function with reduced, normal, or preserved ejection fraction, elevated vascular resistance, fluid and autonomic imbalance, and ventricular dilatation. Despite considerable advances in the treatment of HF over the past few decades, mortality remains substantial. Pharmacological treatments including β-blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and aldosterone antagonists have been proven to prolong the survival of patients with HF. However, there are still instances where patients remain symptomatic, despite optimal use of existing therapeutic agents. This understanding that patients with chronic HF progress into advanced stages despite receiving optimal treatment has increased the quest for alternatives, exploring the roles of additional pathways that contribute to the development and progression of HF. Several pharmacological targets associated with pathogenesis of HF have been identified and novel therapies have emerged. In this work, we review recent evidence from proposed mechanisms to the outcomes of experimental and clinical studies of the novel pharmacological agents that have emerged for the treatment of HF.

Aliskiren-attenuated myocardium apoptosis via regulation of autophagy and connexin-43 in aged spontaneously hypertensive rats

There are controversies about the mechanism of myocardium apoptosis in hypertensive heart disease. The aim of this study was to investigate the relationship among autophagy, Cx43 and apoptosis in aged spontaneously hypertensive rats (SHRs) and establish whether Aliskiren is effective or not for the treatment of myocardium apoptosis. Twenty-one SHRs aged 52 weeks were randomly divided into three groups, the first two receiving Aliskiren at a dose of 10 and 25 mg/kg/day respectively; the third, placebo for comparison with seven Wistar-Kyoto (WKY) as controls. After a 2-month treatment, systolic blood pressure (SBP), heart to bw ratios (HW/BW%) and angiotensin II (AngII) concentration were significantly enhanced in SHRs respectively. Apoptotic cardiomyocytes detected with TUNEL and immunofluorescent labelling for active caspase-3 increased nearly fourfolds in SHRs, with a decline in the expression of survivin and AKT activation, and an increase in caspase-3 activation and the ratio of Bax/Bcl-2. Myocardium autophagy, detected with immunofluorescent labelling for LC3-II, increased nearly threefolds in SHRs, with the up-regulation of Atg5, Atg16L1, Beclin-1 and LC3-II. The expression of Cx43 plaque was found to be down-regulated in SHRs. Aliskiren significantly reduced SBP, HW/BW%, AngII concentration and the expression of AT(1)R. Thus, Aliskiren protects myocardium against apoptosis by decreasing autophagy, up-regulating Cx43. These effects showed a dose-dependent tendency, but no significance. In conclusion, the myocardium apoptosis developed during the hypertensive end-stage of SHRs could be ameliorated by Aliskiren via the regulation of myocardium autophagy and maladaptive remodelling of Cx43.