Approach to Antihypertensive Therapy

The pharmaco-epigenetics of hypertension: a focus on microRNA

Hypertension is a major harbinger of cardiovascular morbidity and mortality. It predisposes to higher rates of myocardial infarction, chronic kidney failure, stroke, and heart failure than most other risk factors. By 2025, the prevalence of hypertension is projected to reach 1.5 billion people. The pathophysiology of this disease is multifaceted, as it involves nitric oxide and endothelin dysregulation, reactive oxygen species, vascular smooth muscle proliferation, and vessel wall calcification, among others. With the advent of new biomolecular techniques, various studies have elucidated a gaping hole in the etiology and mechanisms of hypertension. Indeed, epigenetics, DNA methylation, histone modification, and microRNA-mediated translational silencing appear to play crucial roles in altering the molecular phenotype into a hypertensive profile. Here, we critically review the experimentally determined associations between microRNA (miRNA) molecules and hypertension pharmacotherapy. Particular attention is given to the epigenetic mechanisms underlying the physiological responses to antihypertensive drugs like candesartan, and other relevant drugs like clopidogrel, aspirin, and statins among others. Furthermore, how miRNA affects the pharmaco-epigenetics of hypertension is especially highlighted.

Hypoxic Cardioprotection by New Antihypertensive Compounds in High Salt-Diet Hypertensive Rats: Glucose Transport Participation and Its Possible Pathway

Hypertension (HP) is a health condition that overloads the heart and increases the risk of heart attack and stroke. In an infarction, the lack of oxygen causes an exclusive use of glycolysis, which becomes a crucial source of ATP for the heart with a higher glucose uptake mediated by glucose transporters (GLUTs). Due to the unpleasant effects of antihypertensives, new drugs need to be researched to treat this disease. This study aimed to evaluate the cardioprotective effect of three novel antihypertensive compounds (LQMs, "Laboratorio de Química Medicinal") synthesized from Changrolin under hypoxic conditions with the participation of two primary cardiac GLUT1 and GLUT4 using a high-salt diet HP model. The model used a diet with 10% salt to increase arterial blood pressure in Wistar rats. In isolated cardiomyocytes from these rats, glucose uptake was measured during hypoxia, evaluating the participation of GLUTs with or without the animals' previous treatment with LQM312, 319, and 345 compounds. In silico calculations were performed to understand the affinity of the compounds for the trafficking of GLUTs. Results: Control cells do shift to glucose uptake exclusively in hypoxia (from 1.84 ± 0.09 µg/g/h to 2.67 ± 0.1 µg/g/h). Meanwhile, HP does not change its glucose uptake (from 2.38 ± 0.24 µg/g/h to 2.33 ± 0.26 µg/g/h), which is associated with cardiomyocyte damage. The new compounds lowered the systolic blood pressure (from 149 to 120 mmHg), but only LQM312 and LQM319 improved the metabolic state of hypoxic cardiomyocytes mediated by GLUT1 and GLUT4. In silico studies suggested that Captopril and LQM312 may mimic the interaction with the AMPK γ-subunit. Therefore, these compounds could activate AMPK, promoting the GLUT4 trafficking signaling pathway. These compounds are proposed to be cardioprotective during hypoxia under HP.

Great Sustainability Results From Appropriate Antihypertensive Therapy

Cardiovascular diseases are emerging as a major cause of death and hospitalization in the Western world. For many years, a number of medicines have been placed on the market, in well-established and safe use for antihypertensive therapy. The various classes of antihypertensives in established use include, ACE inhibitors, as monotherapy or in combination with diuretics or calcium antagonists, sartans, calcium antagonists, beta blockers, and diuretics. Among these medicines classes there are differences in mechanism of action, efficacy in reducing blood pression, tolerability, and cost. In fact, there are wide differences in the monthly cost of therapy within each class and among the classes themselves. In this analysis we describe an example about the prescribing trends of antihypertensive drugs at a European sample represented by an Italian health care company of about 1 million inhabitants. Aspects of pharmacoeconomics, pharmacoutilization, and pharmacological differences are described.

Prolonged Diuretic and Renoprotective Effects of a Xanthone Obtained from Garcinia achachairu Rusby in Normotensive and Hypertensive Rats

The previous study showed that 1,5,8-trihydroxy-4',5'-dimethyl-2H-pyrano(2,3 : 3,2)-4-(3-methylbut-2-enyl) xanthone (TDP) obtained from Garcinia achachairu Rusby (Clusiaceae) branches induces acute diuresis in normotensive (NTR) and spontaneously hypertensive rats (SHR) after 8 h of the experiment. In complementarity, the present study evaluated the prolonged diuretic and renoprotective effects of TDP in both NTR and SHR. The animals received, once a day, oral treatment with TDP (0.1 mg/kg), hydrochlorothiazide (10 mg/kg), or vehicle (VEH; 10 mL/kg). At the end of 7 days, the urine, blood, and kidney samples were collected for biochemical and histological analyzes. The urinary volume of both NTR and SHR after 7 days of treatment with the TDP was significantly increased, associated with augmented urinary electrolyte excretion levels. The treatments did not modify the urinary pH values nor the parameters analyzed in plasma (Na⁺, K⁺, Cl^-, and Ca²⁺). Concerning the renal analyzes, when compared with the VEH-treated NTR group, while the activity of the enzymes catalase (CAT) and N-acetyl-β-D-glucosaminidase (NAG), as well as nitrite levels, were increased, the generation of lipid hydroperoxides and the activity of the enzyme myeloperoxidase (MPO) were unaltered. On the other hand, the activities of superoxide dismutase (SOD) and glutathione S-transferase (GST) and the levels of reduced glutathione (GSH) in kidney homogenates of the SHR group were decreased. However, TDP augmented the levels of GSH and GST activities and reduced the levels of nitrite and the activities of CAT and MPO, when compared with VEH-treated only SHR. Besides, the treatment with TDP alleviated the morphological changes of the renal corpuscle region of SHR. Together, these results revealed the prolonged diuretic effect of TDP and their renal protective effect by improving the antioxidative capacity.