Doxazosin Stimulates Galectin-3 Expression and Collagen Synthesis in HL-1 Cardiomyocytes Independent of Protein Kinase C Pathway

Manifestations of Liver Impairment and the Effects of MH-76, a Non-Quinazoline α1-Adrenoceptor Antagonist, and Prazosin on Liver Tissue in Fructose-Induced Metabolic Syndrome

Excessive fructose consumption may lead to metabolic syndrome, metabolic dysfunction-associated fatty liver disease (MAFLD) and hypertension. α1-adrenoceptors antagonists are antihypertensive agents that exert mild beneficial effects on the metabolic profile in hypertensive patients. However, they are no longer used as a first-line therapy for hypertension based on Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) outcomes. Later studies have shown that quinazoline-based α1-adrenolytics (prazosin, doxazosin) induce apoptosis; however, this effect was independent of α1-adrenoceptor blockade and was associated with the presence of quinazoline moiety. Recent studies showed that α1-adrenoceptors antagonists may reduce mortality in COVID-19 patients due to anti-inflammatory properties. MH-76 (1-[3-(2,6-dimethylphenoxy)propyl]-4-(2-methoxyphenyl)piperazine hydrochloride)) is a non-quinazoline α1-adrenoceptor antagonist which, in fructose-fed rats, exerted anti-inflammatory, antihypertensive properties and reduced insulin resistance and visceral adiposity. In this study, we aimed to evaluate the effect of fructose consumption and treatment with α1-adrenoceptor antagonists of different classes (MH-76 and prazosin) on liver tissue of fructose-fed rats. Livers were collected from four groups (Control, Fructose, Fructose + MH-76 and Fructose + Prazosin) and subjected to biochemical and histopathological studies. Both α1-adrenolytics reduced macrovesicular steatosis and triglycerides content of liver tissue and improved its antioxidant capacity. Treatment with MH-76, contrary to prazosin, reduced leucocytes infiltration as well as decreased elevated IL-6 and leptin concentrations. Moreover, the MH-76 hepatotoxicity in hepatoma HepG2 cells was less than that of prazosin. The use of α1-adrenolytics with anti-inflammatory properties may be an interesting option for treatment of hypertension with metabolic complications.

Vulnerable Atherosclerotic Plaque: Is There a Molecular Signature?

Atherosclerosis and its clinical manifestations, coronary and cerebral artery diseases, are the most common cause of death worldwide. The main pathophysiological mechanism for these complications is the rupture of vulnerable atherosclerotic plaques and subsequent thrombosis. Pathological studies of the vulnerable lesions showed that more frequently, plaques rich in lipids and with a high level of inflammation, responsible for mild or moderate stenosis, are more prone to rupture, leading to acute events. Identifying the vulnerable plaques helps to stratify patients at risk of developing acute vascular events. Traditional imaging methods based on plaque appearance and size are not reliable in prediction the risk of rupture. Intravascular imaging is a novel technique able to identify vulnerable lesions, but it is invasive and an operator-dependent technique. This review aims to summarize the current data from literature regarding the main biomarkers involved in the attempt to diagnose vulnerable atherosclerotic lesions. These biomarkers could be the base for risk stratification and development of the new therapeutic drugs in the treatment of patients with vulnerable atherosclerotic plaques.

An Up-to-Date Article Regarding Particularities of Drug Treatment in Patients with Chronic Heart Failure

Since the prevalence of heart failure (HF) increases with age, HF is now one of the most common reasons for the hospitalization of elderly people. Although the treatment strategies and overall outcomes of HF patients have improved over time, hospitalization and mortality rates remain elevated, especially in developed countries where populations are aging. Therefore, this paper is intended to be a valuable multidisciplinary source of information for both doctors (cardiologists and general physicians) and pharmacists in order to decrease the morbidity and mortality of heart failure patients. We address several aspects regarding pharmacological treatment (including new approaches in HF treatment strategies [sacubitril/valsartan combination and sodium glucose co-transporter-2 inhibitors]), as well as the particularities of patients (age-induced changes and sex differences) and treatment (pharmacokinetic and pharmacodynamic changes in drugs; cardiorenal syndrome). The article also highlights several drugs and food supplements that may worsen the prognosis of HF patients and discusses some potential drug-drug interactions, their consequences and recommendations for health care providers, as well as the risks of adverse drug reactions and treatment discontinuation, as an interdisciplinary approach to treatment is essential for HF patients.

MH-76, a Novel Non-Quinazoline α1-Adrenoceptor Antagonist, but Not Prazosin Reduces Inflammation and Improves Insulin Signaling in Adipose Tissue of Fructose-Fed Rats

Background: Quinazoline α₁-adrenoceptors antagonists have been shown to exert moderately favorable effects on the metabolic profile in hypertensive patients. However, based on AntiHypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) results, they are no longer recommended as a first line therapy of hypertension. Recent studies have shown that quinazoline-based α₁-adrenoceptors antagonists (prazosin, doxazosin) induce the apoptosis and necrosis, which may be responsible for ALLHAT outcomes; however, these effects were proven to be independent of α₁-adrenoceptor blockade and were associated with the presence of quinazoline moiety. MH-76 (1-[3-(2,6-dimethylphenoxy)propyl]-4-(2-methoxyphenyl)piperazine hydrochloride)) is a non-quinazoline α₁-adrenoceptor antagonist which, in fructose-fed rats, exerted antihypertensive effect, and, contrary to prazosin, reduced insulin resistance and abdominal adiposity. In this study we aimed to further investigate and compare the effects of MH-76 and prazosin on inflammation in adipose tissue of fructose-fed rats. Methods: Abdominal adipose tissue was collected from four groups of fructose-fed rats (Control, Fructose, Fructose + MH-76 and Fructose + Prazosin) and subjected to biochemical, histopathological and immunohistochemical studies. Moreover, selected tissue distribution studies were performed. Results: Treatment with MH-76 but not with prazosin improved endothelial integrity, reduced adipose tissue inflammation and infiltration by immune cells, resulting in lowering leptin, MCP-1, IL-6, TNF-α and PAI-1 levels. In adipose tissue from Fructose + MH-76 animals, a higher amount of eosinophils accompanied with higher IL-4 concentration was observed. Treatment with MH-76 but not with prazosin markedly reduced phosphorylation of IRS-1 at Ser307. Conclusion: MH-76 may improve insulin signaling in adipose tissue by reducing the pro-inflammatory cytokine production and inhibiting the inflammatory cells recruitment. In contrast, in adipose tissue from animals treated with prazosin, the inflammatory effect was clearly enhanced.

The association of erythropoietin-stimulating agents and increased risk for AV-fistula dysfunction in hemodialysis patients. A retrospective analysis

BACKGROUND

Patients in maintenance hemodialysis (HD) need a patent vascular access for optimal treatment. The recommended first choice is a native arteriovenous fistula (AVF). Complications of AVF are frequent and include thrombosis, stenosis and infections leading to worsening of dialysis efficacy. Some known risk factors are age, gender and the presence of diabetes mellitus. The aim was to investigate if further risk variables are associated with dysfunctional AVF.

METHODS

This retrospective observational study included 153 chronic HD patients (Cases) referred to a total of 473 radiological investigations due to clinically suspected complications of their native AVF. Another group of chronic HD patients (n = 52) who had a native AVF but were without history of previous complications for at least 2 years were controls. Statistical analyses included ANOVA, logistic regression, parametric and non-parametric methods such as Student's T-test and Mann-Whitney test.

RESULTS

Among Cases, at least one significant stenosis (> 50% of the lumen) was detected in 348 occasions. Subsequent PTA was performed in 248 (71%). Median erythropoiesis-stimulating agent (ESA) weekly doses were higher in Cases than in Controls (8000 vs 5000 IU, p < 0.001). Cases received higher doses of intravenous iron/week than the Controls before the investigation (median 50 mg vs 25 mg, p = 0.004) and low molecular weight heparin (LMWH, p = 0.028). Compared to Controls, Cases had a lower level of parathyroid hormone (median 25 vs 20 ρmol/L, p = 0.009). In patients with diabetes mellitus, HbA1c was higher among Cases than Controls (50 vs 38 mmol/mol, p < 0.001). Multiple regression analysis revealed significant associations between Cases and female gender, prescription of doxazocin, and doses of ESA and LMWH. There was no difference between the groups regarding hemoglobin, CRP or ferritin.

CONCLUSION

In conclusion, the present study indicated that the factors associated with AVF problems were high doses of ESA, iron administration, and tendency of thromboembolism (indicated by high LMWH doses); the use of doxazocin prescription, however, requires further investigation.

Ageing-related changes in the levels of β-catenin, CacyBP/SIP, galectin-3 and immunoproteasome subunit LMP7 in the heart of men

Aging is a major risk factor for morbidity and mortality from cardiovascular causes in men. To better understand the cellular processes related to age-related cardiac complications, we undertook research aimed at comparative evaluation of genes expression and distribution of β-catenin, CacyBP/SIP, galectin-3 and LMP7 in the heart of healthy men in different age groups. The study was conducted on the hearts of 12 men (organ donors) without a history of cardiovascular disease, who were divided into two age groups: men under and men over 45 years of age. On paraffin sections, immunohistochemical reactions were performed to detect β-catenin, CacyBP/SIP, galectin-3 and immunoproteasome subunit LMP7. The expression of genes coding β-catenin, CacyBP/SIP, galectin-3 and LMP7 was also evaluated by real-time PCR method. In the heart of men over 45 years old, both gene expression and immunoreactivity of β-catenin, CacyBP/SIP, galectin-3 and LMP7 were stronger compared to younger individuals. The results of the presented studies suggest that β-catenin, CacyBP/SIP, galectin-3 and immunoproteasomes might be involved in the internal regulation of heart homeostasis during ageing.

Galectin-3 Is a Potential Mediator for Atherosclerosis

Atherosclerosis is a multifactorial chronic inflammatory arterial disease forming the pathological basis of many cardiovascular diseases such as coronary heart disease, heart failure, and stroke. Numerous studies have implicated inflammation as a key player in the initiation and progression of atherosclerosis. Galectin-3 (Gal-3) is a 30 kDa β-galactose, highly conserved and widely distributed intracellularly and extracellularly. Gal-3 has been demonstrated in recent years to be a novel inflammatory factor participating in the process of intravascular inflammation, lipid endocytosis, macrophage activation, cellular proliferation, monocyte chemotaxis, and cell adhesion. This review focuses on the role of Gal-3 in atherosclerosis and the mechanism involved and several classical Gal-3 agonists and antagonists in the current studies.

Beneficial effects of non-quinazoline α1-adrenolytics on hypertension and altered metabolism in fructose-fed rats. A comparison with prazosin

BACKGROUND AND AIMS

Metabolic syndrome associated with insulin resistance and hypertension is often caused by excessive fructose consumption. Treatment of hypertension in patients with metabolic syndrome is a difficult task as many antihypertensive drugs have adverse effects on the metabolic profile. We investigated if MH-76 and MH-79, non-quinazoline α₁-adrenoceptor antagonists with an additional ability to stimulate NO/cGMP/K⁺ pathway, ameliorates metabolic syndrome in fructose-fed rats. As reference compound prazosin was used.

METHODS AND RESULTS

Male rats were divided into 5 groups (n = 8) and studied for 18 weeks: group control: standard diet and drinking water; group Fructose: high-fructose diet (20% fructose in drinking water); groups Fructose + MH-76, Fructose + MH-79, Fructose + prazosin: high-fructose diet with subsequent MH-76, MH-79 (5 mg/kg/day ip) or prazosin (0.2 mg/kg/day ip) treatment 12 weeks later. In addition to their antihypertensive effect, the studied compounds reversed endothelial dysfunction, decreased hyperglycemia and hypertriglyceridemia, as well as prevented abdominal adiposity. Moreover, MH-76 reduced insulin resistance and decreased TNF-α concentration and lipid peroxidation in adipose tissue. Prazosin treatment exerted an antihypertensive effect, reduced hyperglycemia but did not improve endothelial dysfunction, insulin resistance, and abdominal adiposity. The lower efficacy of prazosin may be the result of its short half-time and the lack of described pleiotropic effects.

CONCLUSIONS

α₁-adrenoceptor blockade, endothelial protection, TNF-α suppressing and antioxidant activity together with favorable pharmacokinetic parameters determines high efficacy of MH-76, leading to the effective improvement of hemodynamic and metabolic disturbances in metabolic syndrome. The use of non-quinazoline, multiple-targeted α₁-blockers may be an interesting option for treatment of hypertension with metabolic complications.

Galectin-3 in Peripheral Artery Disease. Relationships with Markers of Oxidative Stress and Inflammation

Galectin-3 is a modulator of oxidative stress, inflammation, and fibrogenesis involved in the pathogenesis of vascular diseases. The present study sought to characterize, in patients with peripheral artery disease (PAD), the localization of galectin-3 in arterial tissue, and to analyze the relationships between the circulating levels of galectin-3 and oxidative stress and inflammation. It also sought to compare the diagnostic accuracy of galectin-3 with that of other biochemical markers of this disease. We analyzed femoral or popliteal arteries from 50 PAD patients, and four control arteries. Plasma from 86 patients was compared with that from 72 control subjects. We observed differences in the expression of galectin-3 in normal arteries, and arteries from patients with PAD, with a displacement of the expression from the adventitia to the media, and the intima. In addition, plasma galectin-3 concentration was increased in PAD patients, and correlated with serologic markers of oxidative stress (F2-isoprostanes), and inflammation [chemokine (C−C motif) ligand 2, C-reactive protein, β-2-microglobulin]. We conclude that the determination of galectin-3 has good diagnostic accuracy in the assessment of PAD and compares well with other analytical parameters currently in use.