Effect of verapamil, trandolapril and their combination on vascular function and structure in essential hypertensive patients

Position statement on use of pharmacological combinations in a single pill for treatment of hypertension by Argentine Federation of Cardiology (FAC) and Argentine Society of Hypertension (SAHA)

The present document provides scientific evidence reviewed and analysed by a group of specialist clinicians in hypertension that aims to give an insight into a pharmacological strategy to improve blood pressure control. Evidence shows that most hypertensive patients will need at least two drugs to achieve blood pressure goals. There is ample evidence showing that treatment adherence is inversely related to the number of drugs taken. Observational studies show that use of drug combinations to initiate treatment reduces the time to reach the treatment goal and reduces CVD, especially with single pill combinations (SPCs). This work, based on recommendations of the Argentine Federation of Cardiology and Argentine Society of Hypertension as a reference, aims to review the more recent evidence on SPC, and to serve as guidelines for health professionals in their clinical practice and to the wider use of SPCs for the treatment of hypertension. Evidence from clinical trials on the effectiveness and adverse effects of using SPCs are provided. An analysis is also made of the main contributions of SPCs in special populations, e.g., elderly and diabetic patients, and its use in high risk and resistant hypertension. The effects of SPCs on hypertensive-mediated organ damage is also examined. Finally, we provide some aspects to consider when choosing treatments in the economic context of Latin-America for promoting the most efficient use of resources in a scarce environment and to provide quality information to decision makers to formulate safe, cost-effective, and patient-centered health policies. Finally, future perspectives and limitations in clinical practice are also discussed.

Potential Protective Role of Blood Pressure-Lowering Drugs on the Balance between Hemostasis and Fibrinolysis in Hypertensive Patients at Rest and During Exercise

In patients with hypertension, the triad represented by endothelial dysfunction, platelet hyperactivity, and altered fibrinolytic function disturbs the equilibrium between hemostasis and fibrinolysis and translates into a hypercoagulable state, which underlies the risk of thrombotic complications. This article reviews the scientific evidence regarding some biological effects of antihypertensive drugs, which can protect patients from the adverse consequences of hypertensive disease, improving endothelial function, enhancing antioxidant activity, and restoring equilibrium between hemostatic and fibrinolytic factors. These protective effects appear not to be mediated through blood pressure reduction and are not shared by all molecules of the same pharmacological class.

Combination therapy in the treatment of hypertension

Hypertension is a major preventable risk factor for atherosclerosis and ischemic heart disease. Although modern and effective antihypertensive drugs are available, most patients remain with a suboptimal blood pressure control. Most hypertensive patients will need a combination of antihypertensive agents to achieve the therapeutic goals – recent guidelines recommend initiating treatment with two drugs in those patients with a systolic blood pressure >20 mmHg and/or a diastolic blood pressure >10 mmHg above the goals, and in those patients with high cardiovascular risk. In addition, approximately 25% of patients will require three antihypertensive agents to achieve the therapeutic targets. In this review, we analyse the latest information available regarding the treatment of hypertension with combination therapy.

Nanomedicines for Endothelial Disorders

The endothelium lines the internal surfaces of blood and lymphatic vessels and has a critical role in maintaining homeostasis. Endothelial dysfunction is involved in the pathology of many diseases and conditions, including disorders such as diabetes, cardiovascular diseases, and cancer. Given this common etiology in a range of diseases, medicines targeting an impaired endothelium can strengthen the arsenal of therapeutics. Nanomedicine - the application of nanotechnology to healthcare - presents novel opportunities and potential for the treatment of diseases associated with an impaired endothelium. This review discusses therapies currently available for the treatment of these disorders and highlights the application of nanomedicine for the therapy of these major disease complications.

Stimulation of Cardiomyocyte Regeneratory Reactions under Conditions of Cytopathic Hypercholesterolemia

The regeneratory reactions of cardiomyocytes in the heart under conditions of cytopathic exposure to hypercholesterolemia and during verapamil treatment were studied by immunohistochemical detection of proliferation marker Ki-67 and evaluation of cardiomyocyte count. A 30-day exposure of rats to atherogenic diet led to an increase of Ki-67+ cardiomyocytes by 14.5-16.7 times (p<0.05). The Ki-67 label index in cardiomyocytes remained higher than normally (8-9-fold; p<0.05) after 64 days. It remained elevated (8-11-fold; p<0.05) after verapamil treatment. Evaluation of cardiomyocyte count and of their nuclear status detected various regeneratory strategies: increase of the total cardiomyocyte count, with increase of the percentage of mononuclear cardiomyocytes (particularly in response to verapamil in group 1 rats); decrease of total cardiomyocyte count with increase of the percentage of multinuclear cardiomyocytes (particularly in group 2 rats in response to verapamil).

Expression of ryanodine receptor mRNA and sarcoplasmic Ca²⁺-ATPase mRNA in the myocardium and intracellular reorganization of cardiomyocytes in dyslipidemia and during verapamil treatment

In experiments on rats, atherogenic diet led to hypercholesterolemia, while addition of verapamil to the diet led to the development of hypertriglyceridemia in these animals. Dyslipidemia induced significant changes in the cardiomyocyte ultrastructure (lytic changes in myofibrils and sarcoplasmic matrix and aggravation of autophagocytosis) that were most pronounced after addition of mercazolyl alone to the diet. After 30-day atherogenic diet, we observed a decrease in the relative content of RyR2 mRNA (by 67-73%, p<0.01) and SERCA2a mRNA (by 75-91%, p<0.01) in the myocardium. In 64 days these parameters remained reduced: by 64-72% (p<0.05) and 54-62% (p<0.05), respectively. Verapamil treatment reduced the severity and number of lytic lesions in cardiomyocytes, induced considerable glycogen accumulation in the sarcoplasm and its sequestration, promoted normalization, and prevented pronounced decrease of the relative RyR2 mRNA and SERCA2a mRNA in rat myocardium.

Puerarin attenuates cerebral damage by improving cerebral microcirculation in spontaneously hypertensive rats

Puerariae Lobatae Radix (Gegen in Chinese) is the dried root of Pueraria lobata, a semiwoody, perennial, and leguminous vine native to China. Puerarin is one of the effective components of isoflavones isolated from the root of Pueraria lobata. Previous studies showed that extracts derived from the root of Pueraria lobata possessed antihypertensive effect. Our study is to investigate whether puerarin contributes to prevention of stroke by improving cerebral microcirculation in rats. Materials and Methods. Video microscopy and laser Doppler perfusion imaging on the pia mater were used to measure the diameter of microvessel and blood perfusion in 12-week old spontaneously hypertensive rats (SHRs) and age-matched normotensive WKY rats. Histological alterations were observed by hematoxylin and eosin staining, and microvessel density in cerebral tissue was measured by immunohistochemical analysis with anti-Factor VIII antibody. Cell proliferation was detected by [(3)H]-TdR incorporation, and activities of p42/44 mitogen activated protein kinases (p42/44 MAPKs) were detected by western blot analysis in cultured cerebral microvascular endothelial cells (MECs). Results. Intravenous injection of puerarin relaxed arterioles and increased the blood flow perfusion in the pia mater in SHRs. Puerarin treatment for 14 days reduced the blood pressure to a normal level in SHRs (P < 0.05) and increased the arteriole diameter in the pia mater significantly as compared with vehicle treatment. Arteriole remodeling, edema, and ischemia in cerebral tissue were attenuated in puerarin-treated SHRs. Microvessel density in cerebral tissue was greater with puerarin than with vehicle treatment. Puerarin-treated MECs showed greater proliferation and p42/44 MAPKs activities than vehicle treatment. Conclusions. Puerarin possesses effects of antihypertension and stroke prevention by improved microcirculation in SHRs, which results from the increase in cerebral blood perfusion both by arteriole relaxation and p42/44 MAPKs-mediated angiogenesis.

Endothelial dysfunction in patients with type 2 diabetes post acute coronary syndrome

This single visit study examined whether endothelial function, in addition to cardiovascular (CV) risk factors and plasma microparticle content, was normalised in 15 patients with type 2 diabetes + acute coronary syndrome (ACS) (6 weeks-6 months post cardiac event) undergoing standard clinical care compared to 16 sex- and age-matched healthy controls.

RESULTS

While total and low-density lipoprotein (LDL) cholesterol levels were well controlled in the patients with type 2 diabetes + ACS, residual CV risk profiles such as increased body mass index (BMI), systolic blood pressure, glucose levels and triglycerides and lower high-density lipoprotein (HDL) levels were still apparent. Endothelium-dependent responses to acetylcholine (ACh) were significantly lower in type 2 diabetes + ACS patients compared to controls. Correspondingly, the reactive hyperaemic index (RHI) was lower in the patient cohort. Endothelial microparticle (EMP) levels (CD31(+), CD41(-)) were 40% lower in the patient cohort. Simultaneous analysis of platelet microparticle (PMP) levels (CD41(+)) showed no difference between cohorts.

CONCLUSIONS

Patients with type 2 diabetes suffering from recent ACS exhibit residual CV risk factors despite being on standard clinical care. In addition, these patients continue to present with endothelial dysfunction despite having lower levels of EMPs.

Effects of antihypertensive treatment on endothelial function

Essential hypertension is characterized by endothelial dysfunction due to reduced availability of nitric oxide (NO) secondary to increased generation of oxygen-free radicals. Some antihypertensive drugs may improve or restore endothelial function independently of their blood pressure lowering effect. The newer generation of β-blockers, such as nebivolol and carvedilol, which provide antioxidant activity, can improve endothelial function in patients with hypertension. Dihydropyridine and non-dihydropyridine calcium antagonists reverse impaired endothelium-dependent vasodilatation in different vascular districts, through a mechanism related to an antioxidant effect. However, conflicting results are found in the brachial artery. Angiotensin-converting enzyme (ACE) inhibitors improve endothelial function in subcutaneous, epicardial, brachial, and renal circulation, but they are ineffective in potentiating the impaired response to acetylcholine in the forearm of hypertensive patients. Angiotensin II receptor antagonists can restore endothelium-dependent vasodilatation to acetylcholine in subcutaneous microcirculation but not in that of the forearm muscle. They also improve basal NO release and decrease the vasoconstrictor effect of endogenous endothelin-1. Large-scale clinical trials are required to definitively demonstrate that treatment of endothelial dysfunction can improve the prognosis of patients with essential hypertension.

Improving vascular function in hypertension: potential benefits of combination therapy with amlodipine and renin-angiotensin-aldosterone system blockers

Hypertension is characterized by endothelial dysfunction and increased risk for adverse cardiovascular outcomes. In addition to lowering blood pressure, the calcium-channel blocker amlodipine and blockers of the renin-angiotensin-aldosterone system (angiotensin-converting enzyme inhibitors and angiotensin II type 1 receptor blockers) may further reduce cardiovascular risk by improving endothelial function when used alone or in combination. In fact, the beneficial effects of the combination of amlodipine and a renin-angiotensin-aldosterone system blocker on endothelial function have been found to be greater than the effect of either drug alone, likely due to additive effects on nitric oxide activity. This review summarizes the observed effects of these agents on endothelial function and the complementary mechanisms by which they act, thus providing rationale (beyond blood pressure benefits) for their use in combination.