Effect of prazosin on diabetic nephropathy patients with positive α1-adrenergic receptor autoantibodies and refractory hypertension

Multiple Autoantibodies against Cardiovascular Receptors as Biomarkers in Hypertensive Heart Disease

OBJECTIVES

The pathogenesis of hypertensive heart disease (HHD) remains unclear, which might include autoimmunity. The aim of the present study was to determine whether a relationship exists between the presence of autoantibodies against β1, β2, α1 adrenoreceptors, M2-muscarinic receptors, angiotensin II type1 receptors and HHD.

METHODS

In the present study, 44 patients diagnosed with HHD, 36 patients with hypertension, and 40 controls were also enrolled. The measurement of these 5 autoantibodies was performed by enzyme-linked immunosorbent assay.

RESULTS

The frequencies of autoantibodies against β1, β2, α1 adrenoreceptors, autoantibodies against M2-muscarinic receptors and autoantibodies against angiotensin II type1 receptors were significantly higher in patients with HHD, when compared to patients with hypertension and normal controls (all p < 0.001). In addition, the titers of these 5 autoantibodies significantly increased in patients with HHD. Patients who were positive for all 5 autoantibodies had larger left ventricular end-diastolic diameter (60.5 ± 4.9 vs. 57.8 ± 5.0 vs. 52.5 ± 5.3 mm) and worse left ventricular ejection fraction (45.0 ± 11.0 vs. 56.6 ± 10.4 vs. 57.8 ± 5.3%), when compared to patients not positive for all the 5 autoantibodies and patients negative for all the 5 autoantibodies (χ2 = 9.524, p = 0.009 and χ2 = 7.689, p = 0.021). Furthermore, a significant positive correlation was observed between each 2 autoantibodies of these 5 autoantibodies (all p < 0.001).

CONCLUSION

Multiple autoantibodies of cardiovascular receptors may be involved in the pathogenesis and may be predictive factors of HHD.

The Quest for Type 2 Diabetes Subgroups Identification: Literature Review for a New Subtype Proposal

Type 2 diabetes is considered typically as a heterogeneous disease that englobes the potential different subtypes with distinct pathophysiological mechanisms and/or susceptibility to complications. Some authors have succeeded in the identification of some of these subgroups, but a lot of work remains to be completed. Given the effects of the sympathetic innervation via alpha 1 adrenoceptors on diabetes target organs and the interindividual variability of this receptor sensitivity, the existence of a subtype of type 2 diabetes with hyperactivation of alpha 1 adrenoceptors (HA1A) is proposed. Based on the literature review, the potential characteristics of this phenotype and its susceptibility to certain complications have been identified in this article.

Combination treatment of captopril and prazosin to treat patients with gestational hypertension

Gestational hypertensive disorder is a complication of pregnancy, which adversely affects mother-child health. Captopril and prazosin are two agents that are frequently applied for the treatment of patients with gestational hypertension. However, the cooperative efficacy of captopril and prazosin has been not investigated in a previous study. In the present study, the comprehensive treatment of captopril and prazosin for the treatment of patients with gestational hypertension was investigated. A total of 324 patients with gestational hypertension were recruited to analyze the therapeutic effects of captopril and prazosin in patients with gestational hypertension. The duration of the treatment, dose-limiting toxicities and maximum tolerated dose of captopril and prazosin were examined in this cohort. Furthermore, the levels of blood pressure and proteinuria were also examined in patients with gestational hypertension who received treatment with captopril and/or prazosin with placebo as a control. Serum levels of vasodilation-converting enzyme and α-adrenergic receptor were also examined prior to and during the 4-week post-treatment period. It was observed that the most common treatment-emergence adverse events were hypertension and proteinuria following 4-week treatments. The data revealed that captopril or prazosin treatments significantly ameliorated gestational hypertension and symptoms compared with placebo (P<0.01). Notably, the combination of captopril and prazosin treatments significantly ameliorated hypertension and proteinuria and reduced the expression levels of vasodilation-converting enzyme and α-adrenergic receptor (all P<0.01), which contributed to beneficial effects on complications and blood coagulation mechanism compared with either captopril or prazosin treatment. In conclusion, the present clinical study indicated that combination treatment of captopril and prazosin exhibited more efficient outcomes than the single agent by improving gestational hypertension, indicating that a comprehensive therapeutic regimen of captopril and prazosin may be a potential clinical opinion for patients with gestational hypertension.

Prazosin protects myocardial cells against anoxia-reoxygenation injury via the extracellular signal‑regulated kinase signaling pathway

Ischemic heart disease (including coronary arterial atherosclerosis, or vascular cavity stenosis or occlusion) remains the leading cause of disease-associated mortality worldwide. Prazosin, a receptor blocker of postsynaptic adrenaline, is essential in expanding peripheral arteries, which decreases peripheral vascular resistance, and regulates anti-hypertensive action. However, the mechanisms underlying the effects of prazosin have not been fully elucidated. The aim of the present study was to investigate the protective effects of prazosin on myocardial cells against anoxia-reoxygenation injury in a mouse model. The regulatory effects of prazosin on blood lipid levels and blood pressure were investigated in experimental mice. Furthermore, inflammation responses and oxidative stress in myocardial cells were analyzed in mice treated with prazosin. Apoptotic myocardial cells were investigated in experimental mice treated with prazosin. In addition, apoptotic gene expression levels were evaluated in myocardial cells. Extracellular signal-regulated kinase (ERK) expression and phosphorylation was investigated in myocardial cells in mice with anoxia-reoxygenation injury following prazosin treatment. The activity and expression levels of nuclear factor of activated T cells (NF-AT), activator protein 1 (AP-1) and necrosis factor (NF)-κB were observed in myocardial cells. Furthermore, histological analyses were performed to investigate the benefits of prazosin treatment on anoxia-reoxygenation injury. The results of the present study identified that prazosin decreased the expression levels of inflammatory factors, interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-10 and IL-1 in the serum of mice exhibiting hypoxia/reoxygenation injury. Oxidative stress was observed to be improved and the apoptosis rate was decreased in myocardial cells in anoxia-reoxygenation injury model mice treated with prazosin. ERK expression and phosphorylation was upregulated, and expression levels of NF-AT, AP-1 and NF-κB were downregulated in the myocardial cells of mice treated with prazosin. Blood lipid levels and blood pressure of the anoxia-reoxygenation injury model mice were markedly improved following treatment with prazosin. Histological analysis indicated that the area, circumference fragmentation and segmentation of myocardial cells were significantly improved following prazosin treatment. Thus, these results indicate that prazosin treatment decreases inflammation responses, oxidative stress, and apoptosis of myocardial cells via regulation of the ERK signaling pathway. The findings indicate that prazosin may present as a potential therapeutic agent for the treatment of hypoxia/reoxygenation injury.

Doxazosin attenuates renal matrix remodeling mediated by anti-α1-adrenergic receptor antibody in a rat model of diabetes mellitus

Diabetic nephropathy is a major complication of diabetes mellitus (DM). Recent studies suggest that immunological mechanisms have a key role in the pathogenesis of DM, therefore these mechanisms may be important targets for diabetes therapy. The present study evaluated the effects of anti-α₁-adrenergic receptor antibody (α₁-R Ab) mediation and doxazosin treatment in a rat model of DM. It was observed that levels of 24-h urinary protein, serum creatinine and transforming growth factor-β₁ in DM were significantly increased after α₁-R Ab mediation (all P<0.05). In addition, electron microscopy identified severe damage in the renal tissue microstructures of DM rats following α₁-R Ab mediation, while only mild abnormalities were observed in that of healthy rats mediated with α₁-R Ab and of untreated DM rats. No marked abnormalities were observed in the renal tissue of healthy blank controls. Furthermore, in DM rats treated with α₁-R Ab mediation + doxazosin intervention, the expression of TGF-β₁ significantly decreased, and renal functions and renal matrix remodeling were significantly improved, relative to untreated DM controls (P<0.01). These results suggest that α₁-R Ab may be involved in renal matrix remodeling during DM, and that kidney protection during DM may be achieved through treatment with corresponding receptor antagonists.