Targeted Strategy in Lipid-Lowering Therapy.

Dyslipidemia is characterized by a diminished lipid profile, including increased level of total cholesterol and low-density lipoprotein cholesterol (LDL-c) and reduced level of high-density lipoprotein cholesterol (HDL-c). Lipid-lowering agents represent an efficient tool for the prevention or reduction of progression of atherosclerosis, coronary heart diseases and metabolic syndrome. Statins, ezetimibe, and recently proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are the most effective and used drugs in clinical lipid-lowering therapy. These drugs are mainly aimed to lower cholesterol levels by different mechanisms of actions. Statins, the agents of the first-line therapy-known as 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitors-suppress the liver cholesterol synthesis. Ezetimibe as the second-line therapy can decrease cholesterol by inhibiting cholesterol absorption. Finally, the PCSK9 inhibitors act as an inducer of LDL excretion. In spite of their beneficial lipid-lowering properties, many patients suffer from their serious side effects, route of administration, or unsatisfactory physicochemical characteristics. Clinical demand for dose reduction and the improvement of bioavailability as well as pharmacodynamic and pharmacokinetic profile has resulted in the development of a new targeted therapy that includes nanoparticle carriers, emulsions or vaccination often associated with another more subtle form of administration. Targeted therapy aims to exert a more potent drug profile with lipid-lowering properties either alone or in mutual combination to potentiate their beneficial effects. This review describes the most effective lipid-lowering drugs, their favorable and adverse effects, as well as targeted therapy and alternative treatments to help reduce or prevent atherosclerotic processes and cardiovascular events.

Angiotensin System Modulations in Spontaneously Hypertensive Rats and Consequences on Erythrocyte Properties; Action of MLN-4760 and Zofenopril.

Various pathologies (COVID-19 including) are associated with abnormalities in erythrocyte properties. Hypertension represents an unfavorable condition for erythrocyte quality and is the most prevalent risk factor in COVID-19 patients. ACE2 downregulation that is typical of these patients can further deteriorate cardiovascular health; however, its consequences on erythrocyte properties are not known yet. The aim was to investigate the effect of ACE2 inhibition and the potential beneficial effect of zofenopril on erythrocytes in spontaneously hypertensive rats. ACE2 inhibition induced by MLN-4760 (1 mg/kg/day for 2 weeks) led to deterioration of erythrocyte morphology and osmotic resistance, but plasma markers of oxidative stress, erythrocyte deformability, nitric oxide production and Na,K-ATPase activity were not significantly affected. Zofenopril administration (10 mg/kg/day, initiated after 4-day-lasting ACE2 inhibition) resulted in unexpected increase in angiotensin II plasma levels in both control and ACE-inhibited spontaneously hypertensive rats, but in normalization of osmotic resistance in ACE2-inhibited rats. The overall effect of zofenopril on erythrocyte qualities could be evaluated as beneficial.

Antioxidant Effect of Lonicera caerulea L. in the Cardiovascular System of Obese Zucker Rats.

Lonicera caerulea L. (Loni) represents a promising source of beneficial polyphenols with therapeutical potential in cardiovascular diseases. We aimed to study the effects of Loni and coenzyme Q10 (CoQ10) on selected cardiometabolic parameters and NO/ROS balance in obese Zucker rats. Male Zucker rats were divided into the control group and groups treated with CoQ10 (30 mg/kg/day) or Loni (5 g/kg/day) for 6 weeks. Blood pressure, body weight, heart weight, and plasma lipid profile were determined. NOS activity and protein expressions of eNOS, SOD, NADPH oxidase, and NF-kappa B were measured in the heart and aorta. Neither body weight nor blood pressure were significantly changed after six weeks of Loni or CoQ10 treatment. Both Loni and CoQ10 decreased the plasma LDL level. Moreover, Loni decreased the total cholesterol level. The total NOS activity did not change in the heart after the treatments. However, in the aorta, Loni treatment increased NOS activity and protein expression of SOD and decreased expressions of NADPH oxidase and NF-kappa B compared to both the control and CoQ10 groups. There were no changes in the eNOS protein expression within the groups. In conclusion, it seems that the antioxidant effect of Loni was responsible for both the decrease of plasma LDL and the total cholesterol levels and the increase of vascular NOS activity.

Vascular Effects of Low-Dose ACE2 Inhibitor MLN-4760-Benefit or Detriment in Essential Hypertension?

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infects host cells through angiotensin-converting enzyme 2 (ACE2). Concurrently, the product of ACE2 action, angiotensin 1-7 (Ang 1-7), binds to Mas receptors within the cardiovascular system and provides protective effects. Therefore, it is crucial to reveal the role of ACE2 inhibition, especially within pre-existing cardiovascular pathologies. In our study, we imitated the action of SARS-CoV-2 in organisms using the low dose of the ACE2 inhibitor MLN-4760 with the aim of investigating to what degree ACE2 inhibition is detrimental to the cardiovascular system of spontaneously hypertensive rats (SHRs), which represent a model of human essential hypertension. Our study revealed the complex action of MLN-4760 in SHRs. On the one hand, we found that MLN-4760 had (1) (pro)obesogenic effects that negatively correlated with alternative renin-angiotensin system activity and Ang 1-7 in plasma, (2) negative effects on ACE1 inhibitor (captopril) action, (3) detrimental effects on the small arteries function and (4) anti-angiogenic effect in the model of chick chorioallantoic membrane. On the other hand, MLN-4760 induced compensatory mechanisms involving strengthened Mas receptor-, nitric oxide- and hydrogen sulfide-mediated signal transduction in the aorta, which was associated with unchanged blood pressure, suggesting beneficial action of MLN-4760 when administered at a low dose.

Therapeutic Potential of Polyphenols-Loaded Polymeric Nanoparticles in Cardiovascular System.

Numerous studies document an increased production of reactive oxygen species (ROS) with a subsequent decrease in nitric oxide (NO) bioavailability in different cardiovascular diseases, including hypertension, atherosclerosis, and heart failure. Many natural polyphenols have been demonstrated to decrease ROS generation and/or to induce the endogenous antioxidant enzymatic defense system. Moreover, different polyphenolic compounds have the ability to increase the activity/expression of endothelial nitric oxide synthase (eNOS) with a subsequent enhancement of NO generation. However, as a result of low absorption and bioavailability of natural polyphenols, the beneficial effects of these substances are very limited. Recent progress in delivering polyphenols to the targeted tissues revealed new possibilities for the use of polymeric nanoparticles in increasing the efficiency and reducing the degradability of natural polyphenols. This review focuses on the effects of different natural polyphenolic substances, especially resveratrol, quercetin, curcumin, and cherry extracts, and their ability to bind to polymeric nanoparticles, and summarizes the effects of polyphenol-loaded nanoparticles, mainly in the cardiovascular system.

The role of resistin on metabolic syndrome-induced erectile dysfunction and the possible therapeutic effect of Boldine.

BACKGROUND: Resistin is known as a potential mediator of obesity-associated insulin resistance. The high resistin level disrupts nitric oxide (NO)-mediated relaxation which is also important in erectile function. An antioxidant alkaloid, Boldine, is known as anti-diabetic and protects endothelial functions. OBJECTIVES: We aimed to investigate resistin expression in penile tissue in the presence of insulin resistance (IR) and the effect of Boldine treatment on erectile functions in the metabolic syndrome (MetS) rat model. MATERIALS AND METHODS: Wistar rats were randomly divided into three groups: Control, MetS, and boldine treated MetS group. MetS parameters were assessed by serum triglycerides (TG), uric acid (UA), glucose, insulin levels, HOMA index, and waist circumference (WC)/tibia length (TL) ratio. To evaluate erectile functions, intracavernous pressure (ICP)/mean arterial pressure (MAP) ratio was performed during cavernous nerve stimulation. Protein expressions of resistin, endothelial nitric oxide synthase (eNOS), p(S1177) eNOS, and insulin receptor-ß were evaluated by Western blotting. RESULTS: TG, glucose, insulin levels, weight, WC/TL ratio, HOMA index and resistin expression in penile tissue were significantly increased and ICP/MAP values, and p (S1177) eNOS expression in penile tissue were decreased in MetS group. Boldine treatment enhanced ICP/MAP values, insulin receptor-ß and p(S1177) eNOS expressions compared with the MetS group. DISCUSSION AND CONCLUSION: MetS caused a deterioration in erectile function accompanied by an increase in resistin expression and a reduction in eNOS enzyme activation in the rat penile tissues. Boldine treatment resulted in an improvement in erectile function, independent of resistin expression.

Beneficial Effects of Cornelian Cherries on Lipid Profile and NO/ROS Balance in Obese Zucker Rats: Comparison with CoQ10.

Cornelian cherries (CCs) belong to promising anti-obesity substances. We aimed to study effects of coenzyme Q10 (CoQ10) and two varieties of CCs on lipid profile, ROS, and nitric oxide (NO) production in obese rats. Male Zucker rats were divided into the control group and groups treated with CoQ10 (30mg/kg/day), or CC varieties: Koralovij Marka (KM) and Wild Type (WT) (5 g/kg/day, n = 6 in each group) for 6 weeks. Blood pressure (BP), bodyweight, relative heart weight, and plasma lipid profile were determined. NOS activity and expressions of eNOS, SOD, and NADPH oxidase were determined in the left ventricle (LV) and aorta. Among CC groups, KM decreased bodyweight and WT relative heart weight. Neither CoQ10 nor CCs affected BP. CoQ10 did not affect lipid profile and NOS activity either in the LV or aorta. On the other hand, WT decreased cholesterol and LDL levels. KM and WT increased NOS activity in the aorta, while not affecting the activity in the LV. KM increased eNOS expression and did not affect ROS production, while WT increased SOD and decreased NADPH oxidase without affecting eNOS expressions in both tissues. In conclusion, CCs showed better beneficial effects than CoQ10 in all parameters studied.