New developments in the pharmacological treatment of chronic heart failure

In recent years, rapid growth in the understanding of the pathophysiology of chronic heart failure has allowed for insights into many potential new therapeutic strategies. Yet until now, despite sound biological basis for efficacy and success in early-Phase studies, novel agents have not stood up to the scrutiny of late-Phase clinical trials. Indeed, remarkably negative results have been observed for vasopeptidase inhibitors, endothelin receptor antagonists and agents which block immune activation. However, efficacy data from other novel agents are still awaited, including the selective aldosterone receptor antagonist eplerenone, arginine vasopressin inhibitors, erythropoietin and hydroxy-methyl-glutaryl coenzyme A reductase inhibitors. Other classes of drugs which may enter clinical development include cardiac metabolic agents, matrix metalloproteinase inhibitors and advanced glycation end product antagonists. That the mortality and morbidity of patients with chronic heart failure remain unacceptably high makes the ongoing commitment to exploration of new drug therapies for the condition critical.     

Evaluation of eplerenone in the subgroup of EPHESUS patients with baseline left ventricular ejection fraction <or=30%

AIMS: Because of the prognostic importance of LV dysfunction following an AMI and the increasing use of electrical and/or mechanical interventions in patients with LV systolic dysfunction, this retrospective analysis of EPHESUS patients with LVEF eplerenone in this setting. METHODS AND RESULTS: In EPHESUS, 6,632 patients with LVEF eplerenone 25 mg/day titrated to 50 mg/day or placebo for a mean follow-up of 16 months. Treatment with eplerenone in the subgroup of patients with LVEF eplerenone compared with placebo. Within 30 days of randomization, eplerenone resulted in relative risk reductions of 43% for all-cause mortality (P=0.002), 29% for CV mortality/CV hospitalization (P=0.006), and 58% for SCD (P=0.008). CONCLUSIONS: Treatment with eplerenone plus standard therapy in patients with post-AMI HF and LVEF 相似文献   

Effects of aldosterone and related steroids on LPS-induced increased expression of inducible NOS in rat aortic smooth muscle cells

BACKGROUND AND PURPOSE

Expression of inducible NOS (iNOS) is important in certain inflammatory diseases. We determined if the hormone aldosterone, a mineralocorticoid receptor (MR) agonist, affects LPS activation of iNOS expression in rat aortic smooth muscle cells (RASMC).

EXPERIMENTAL APPROACH

Cultured RASMC were treated with LPS, with or without agonists/antagonists of steroid receptors. iNOS expression was determined by nitrite assays on culture medium removed from treated cells and by immunoblotting of cell protein extracts.

KEY RESULTS

LPS (1 µg·mL⁻¹) increased nitrite and iNOS protein above that in control (untreated) cells. These effects of LPS were reduced by aldosterone (0.1–10 µM). The MR antagonists, eplerenone (10 µM) and spironolactone (10 or 50 µM), did not inhibit these actions of 1 µM aldosterone, but the latter were prevented by 10 µM mifepristone, a glucocorticoid (GR) and progestogen receptor (PR) antagonist. Mifepristone also prevented the reduction of LPS-induced nitrite increase produced by 1 µM dexamethasone (GR agonist) and 10 µM progesterone (PR agonist). Spironolactone (10–50 µM) by itself decreased LPS-induced increases in nitrite and iNOS protein. Mifepristone (10 µM) partially reversed these effects of 10 µM spironolactone, but not those of 50 µM; the effects of 50 µM spironolactone were also unchanged when mifepristone was increased to 50 µM.

CONCLUSIONS AND IMPLICATIONS

This pharmacological profile suggests that aldosterone, and possibly 10 µM spironolactone, use mechanisms that are dependent on PR and/or GR, but not MR, to inhibit iNOS induction in RASMC. With 50 µM spironolactone, other inhibitory mechanisms requiring further investigation may become predominant.     

Targeting the aldosterone pathway in cardiovascular disease

Accumulated evidence has demonstrated that aldosterone is a key player in the pathogenesis of cardiovascular (CV) disease. Multiple clinical trials have documented that intervention in the aldosterone pathway can reduce blood pressure and lower albuminuria and improve outcome in patients with heart failure or myocardial infarction. Recent studies have unraveled details about the role of aldosterone at the cellular level in CV disease. The relative importance of glucocorticoids and aldosterone in terms of mineralocorticoid receptor activation is currently being debated. Also, studies are addressing which aldosterone modulator to use, which timing of treatment to aim for, and in which population to intervene. This review provides an overview of recent developments in the understanding of the role of aldosterone in CV disease, with particular reference to mechanisms and potential targets of intervention. Finally, ongoing or desirable clinical trials in the field are highlighted. The review is partly based on discussions between basic scientists and clinical trialists at the Cardiovascular Clinical Trials Forum 2009 and subsequently updated to encompass the most recent developments.     

依普利酮对环孢素A急性肾损伤小管上皮细胞坏死及再生的作用

目的观察盐皮质激素受体阻断剂依普利酮保护环孢素A肾病小管上皮细胞的作用。方法经口灌服环孢素A(100 mg.kg-1.d-1),诱导小鼠急性肾脏损伤,给予依普利酮100 mg.kg-1.d-1治疗,d 5将5-溴脱氧尿嘧啶核苷(40mg.kg-1.d-1)经微型渗透泵皮下注入,10 d后摘取肾脏,HE、PAS检测肾脏病理改变,免疫组化检测5-溴脱氧尿嘧啶核苷阳性细胞标记再生细胞。结果肾脏病理显示环孢素A组小管上皮细胞坏死、小球包氏囊增厚、间质纤维成分沉积,凋亡细胞增多,免疫组化显示再生细胞数量减少,依普利酮治疗组上皮细胞坏死减轻,间质纤维沉积减少,再生细胞明显增多。结论依普利酮可以通过对醛固酮受体的阻断减轻环孢素A诱导的急性肾脏损伤。     

国产依普利酮对家兔急性心肌梗死后心功能的影响

目的 探讨依普利酮对家兔心肌梗死后心功能的影响.方法 家兔22只,开胸结扎冠状动脉左心室支制成急性心肌梗死（AMI）动物模型,制模成功后随机分为治疗组与对照组,治疗组家兔给予依普利酮治疗,对照组无药物干预,4周后检测2组各项心功能指标的改变,评价依普利酮对家兔AMI后心功能的影响.结果 18只家兔制模成功,4周后与对照组比较,依普利酮明显改善家兔左心室射血分数（LVEF）,显著降低左心室舒张末压（LVEDP）,差异有统计学意义（P〈0.05）.结论 依普利酮可明显改善家兔AMI后的心功能.     

依普利酮中间体坎利酮的合成工艺改进

目的改进依普利酮中间体坎利酮的合成工艺.方法以去氢表雄酮为起始原料,经过氧化、烯醇醚化、环氧化、环缩合、脱羧和脱氢等6步反应合成坎利酮.结果合成了目标化合物坎利酮,其结构经IR、1H-NMR、13C-NMR和FAB-MS等方法确证.总收率为57.9%.结论与文献报道的工艺相比,改进后的工艺更为安全简便、步骤较少且收率较高.     

Eplerenone in hypertension

Appreciation of the role of aldosterone in cardiovascular and renal disease has increased in the last 50 years. The use of spironolactone was limited by adverse sexual effects, including gynaecomastia. Eplerenone is a newer aldosterone antagonist that is much more selective, with minimal affinity for progesterone and androgenic receptors; therefore, there are very few reports of adverse sexual effects. A review of published trials shows that eplerenone reduces blood pressure (BP) in a dose-dependent manner, from 50 to 200 mg/day, and to a similar degree as enalapril. It has an additive effect when given to patients inadequately controlled on an angiotensin-converting enzyme inhibitor or an angiotensin-receptor blocker. Eplerenone performs better than losartan in African-American patients and lowers BP regardless of initial plasma renin activity. The risk of hyperkalaemia is low, similar to that of enalapril, and < 1% of patients have had to be withdrawn from studies because of elevated serum potassium levels. Eplerenone is an effective, well-tolerated antihypertensive agent that may be used alone or in conjunction with other agents; apart from the risk of hyperkalaemia, adverse effects are similar to placebo.     

A German family with glucocorticoid-remediable aldosteronism.

BACKGROUND: The prevalence of primary hyperaldosteronism (PHA) in the hypertensive population has increased in recent years. Glucocorticoid-remediable aldosteronism (GRA) is a rare monogenic form of PHA. Here we report a German family with GRA. Since the phenotype of GRA varies widely, we asked whether recommended algorithms for PHA diagnosis distinguish GRA from other forms of PHA. METHODS: Plasma aldosterone (pg/ml) and renin (pg/ml) levels were determined in three hypertensive family members with GRA before and after sodium loading with 2 l of saline (0.9%), during posture and after 1 week of 2 mg dexamethasone daily. 24 h blood pressure and urinary excretion of aldosterone, cortisol precursors and metabolites were measured before and after dexamethasone. Southern blot hybridization and long-range PCR were performed to identify the chimeric gene. RESULTS: All three affected patients had normal potassium levels but markedly increased aldosterone/renin ratios of 472, 213 and >322 (normal range<50) indicating PHA. Sodium loading failed to lower plasma aldosterone below the threshold of 50 pg/ml in all patients. During posture, aldosterone increased in one but decreased in both other GRA patients. Elevated 18-hydroxycortisol, free aldosterone and its main metabolite aldosterone-18-glucuronid and tetrahydroaldosterone returned to normal range after 1 week dexamethasone in all patients, but blood pressure was reduced only in one patient. The chimeric gene was identified in affected family members by Southern blot and PCR. CONCLUSIONS: The aldosterone/renin ratio is a valid screening and sodium loading a valid confirmation test in GRA. Determination of elevated urinary excretion of specific aldosterone metabolites and identification of the chimeric gene are mandatory since a lacking blood pressure response to dexamethasone can be misleading.