Apelin as a Potential Treatment for Chronic Kidney Disease: The AlPaCKa Study
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 46
- 试验地点
- 2
- 主要终点
- Change in forearm blood flow
研究概览
简要总结
Chronic kidney disease (CKD) affects 8-16% of the world's population, and is independently associated with cardiovascular disease (CVD). As renal function declines, rates of major adverse cardiovascular events, cardiovascular and all-cause mortality increase. In addition to hypertension, increased arterial stiffness is characteristic of CKD, a marker of CVD risk, and an independent predictor of mortality in CKD patients. The endothelium is an important regulator of arterial stiffness, and endothelial dysfunction is a feature of CKD and a predictor of CVD. Current treatment of CKD is limited and aims to reduce blood pressure and proteinuria through the use of angiotensin converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARB). However, many patients still progress to end-stage renal failure and often these patients die as a result of CVD.
A novel peptide, apelin, is proposed to be a potential treatment for CKD, with additional cardiovascular benefits. The AlPaCKa study investigators will carry out forearm blood flow and renal clearance studies in 25 patients with CKD and 25 matched healthy volunteers to determine the effects of apelin on cardiovascular and renal parameters. It is hoped apelin will be confirmed as a potential future treatment for CKD.
详细描述
The apelins are a family of peptides whose most abundant isoform is [Pyr1]apelin-13. This binds to a single G protein coupled receptor known as 'APJ', which is widely expressed particularly in endothelium and cardiomyocytes. Apelin is the most powerful inotropic agent discovered to date, and apelin infusion into healthy humans leads to endothelium-dependent vasodilatation and BP lowering. Given its vasodilatory and inotropic effects, apelin is being investigated as a novel therapy for heart failure and pulmonary arterial hypertension, both of which are features of CKD. The apelin/APJ system is widely expressed in the human kidney (endothelium, smooth muscle cells, glomeruli) with a predominance in the renal medulla. It is recognised to have a role in fluid homeostasis, and apelin infusion in rodents leads to a dose-dependent diuresis but it is difficult to discriminate how much of this is due to renal vasodilatation as opposed to a direct tubular effect. However, it has been shown that apelin counteracts the antidiuretic effect of vasopressin at the tubular level. Evidence therefore suggests that apelin could have additional cardioprotective effects in CKD and could promote natriuresis and diuresis. To date there are no clinical studies of the actions of apelin in the kidney in health or CKD, or its effect on systemic haemodynamics in CKD.
Twenty-five patients with CKD and 25 matched healthy volunteers will undergo forearm blood flow studies with acetylcholine, sodium nitroprusside and apelin to determine the local haemodynamic effects of apelin in CKD, specifically the effects on endothelial function. The same subjects will then complete two renal clearance studies during systemic apelin / placebo infusion (randomised and double-blinded), by standard renal para-aminohippurate and inulin clearance techniques. Blood and urine samples will be collected every 30 minutes. This will allow the effects of apelin on renal function, renal blood flow, proteinuria, natriuresis and diuresis to be demonstrated. Cardiovascular effects will be determined by systemic bioimpedance measures and pulse wave velocity. This study aims to open a new area of clinical research with apelin.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Adults >18yrs
- •Stable, non-diabetic chronic kidney disease stages 1 - 4 as defined by Kidney Disease: Improving Global Outcomes (KDIGO) 2012 classification (estimated Glomerular Filtration Rate (eGFR) >15ml/min/1.73m2)
- •Clinically optimised on an angiotensin converting enzyme inhibitor / angiotensin receptor blocker, or intolerant to these agents.
排除标准
- •Age <18 years
- •Diabetes mellitus
- •Overt cardiovascular disease
- •Blood pressure >160/100mmHg
- •Estimated GFR of <15ml/min/1.73m2
- •Renal transplant recipients
- •Haemodialysis / peritoneal dialysis patients
- •Serum albumin <30g/L
- •Patients receiving tolvaptan therapy for polycystic kidney disease
- •Patients not medically fit to attend for study visits
- •Patients without mental capacity or willingness to provide informed consent
- •History of multiple and/or severe allergic reaction to drugs (including study drugs) or food
- •Patients who are pregnant or breast feeding
结局指标
主要结局
Change in forearm blood flow
时间窗: 1 hour
Venous occlusion plethysmography
Change in renal blood flow
时间窗: 4 hours
Para-aminohippurate clearance study
次要结局
- Change in chorioretinal metrics as assessed by optical coherence tomography (OCT(4 hours)
- Change in natriuresis(4 hours)
- Change in diuresis(4 hours)
- Change in proteinuria(4 hours)
- Change in blood pressure(4 hours)
- Change in arterial stiffness(1 hour)