Cardiac Rehabilitation Institute, Sheba Medical Center, 52621 Tel-Hashomer, Israel.
Cardiovasc Diabetol. 2012 Nov 14;11:140. doi: 10.1186/1475-2840-11-140.
All fibrates are peroxisome proliferators-activated receptors (PPARs)-alpha agonists with ability to decrease triglyceride and increase high density lipoprotein- cholesterol (HDL-C). However, bezafibrate has a unique characteristic profile of action since it activates all three PPAR subtypes (alpha, gamma and delta) at comparable doses. Therefore, bezafibrate operates as a pan-agonist for all three PPAR isoforms. Selective PPAR gamma agonists (thiazolidinediones) are used to treat type 2 diabetes mellitus (T2DM). They improve insulin sensitivity by up-regulating adipogenesis, decreasing free fatty acid levels, and reversing insulin resistance. However, selective PPAR gamma agonists also cause water retention, weight gain, peripheral edema, and congestive heart failure. The expression of PPAR beta/ delta in essentially all cell types and tissues (ubiquitous presence) suggests its potential fundamental role in cellular biology. PPAR beta/ delta effects correlated with enhancement of fatty acid oxidation, energy consumption and adaptive thermogenesis. Together, these data implicate PPAR beta/delta in fuel combustion and suggest that pan-PPAR agonists that include a component of PPAR beta/delta activation might offset some of the weight gain issues seen with selective PPAR gamma agonists, as was demonstrated by bezafibrate studies. Suggestively, on the whole body level all PPARs acting as one orchestra and balanced pan-PPAR activation seems as an especially attractive pharmacological goal. Conceptually, combined PPAR gamma and alpha action can target simultaneously insulin resistance and atherogenic dyslipidemia, whereas PPAR beta/delta properties may prevent the development of overweight. Bezafibrate, as all fibrates, significantly reduced plasma triglycerides and increased HDL-C level (but considerably stronger than other major fibrates). Bezafibrate significantly decreased prevalence of small, dense low density lipoproteins particles, remnants, induced atherosclerotic plaque regression in thoracic and abdominal aorta and improved endothelial function. In addition, bezafibrate has important fibrinogen-related properties and anti-inflammatory effects. In clinical trials bezafibrate was highly effective for cardiovascular risk reduction in patients with metabolic syndrome and atherogenic dyslipidemia. The principal differences between bezafibrate and other fibrates are related to effects on glucose level and insulin resistance. Bezafibrate decreases blood glucose level, HbA1C, insulin resistance and reduces the incidence of T2DM compared to placebo or other fibrates. Currently statins are the cornerstone of the treatment and prevention of cardiovascular diseases related to atherosclerosis. However, despite the increasing use of statins as monotherapy for low density lipoprotein- cholesterol (LDL-C) reduction, a significant residual cardiovascular risk is still presented in patients with atherogenic dyslipidemia and insulin resistance, which is typical for T2DM and metabolic syndrome. Recently, concerns were raised regarding the development of diabetes in statin-treated patients. Combined bezafibrate/statin therapy is more effective in achieving a comprehensive lipid control and residual cardiovascular risk reduction. Based on the beneficial effects of pan-PPAR agonist bezafibrate on glucose metabolism and prevention of new-onset diabetes, one could expect a neutralization of the adverse pro-diabetic effect of statins using the strategy of a combined statin/fibrate therapy.
所有贝特类药物都是过氧化物酶体增殖物激活受体 (PPAR) -α 激动剂,具有降低甘油三酯和增加高密度脂蛋白胆固醇 (HDL-C) 的能力。然而,苯扎贝特具有独特的作用特征,因为它在可比剂量下激活所有三种 PPAR 亚型(α、γ 和 δ)。因此,苯扎贝特是所有三种 PPAR 同工型的泛激动剂。选择性过氧化物酶体增殖物激活受体 γ 激动剂(噻唑烷二酮类)用于治疗 2 型糖尿病 (T2DM)。它们通过上调脂肪生成、降低游离脂肪酸水平和逆转胰岛素抵抗来提高胰岛素敏感性。然而,选择性过氧化物酶体增殖物激活受体 γ 激动剂也会导致水潴留、体重增加、外周水肿和充血性心力衰竭。PPARβ/δ在几乎所有细胞类型和组织中的表达(普遍存在)表明其在细胞生物学中具有潜在的基本作用。PPARβ/δ 的作用与增强脂肪酸氧化、能量消耗和适应性产热有关。这些数据共同表明,PPARβ/δ 参与了燃料燃烧,并表明包含 PPARβ/δ 激活成分的泛 PPAR 激动剂可能会抵消选择性过氧化物酶体增殖物激活受体 γ 激动剂引起的一些体重增加问题,这一点已被苯扎贝特研究证实。暗示性地,在整个身体水平上,所有作为一个管弦乐队的 PPAR 似乎平衡的泛 PPAR 激活是一个特别有吸引力的药理学目标。从概念上讲,联合 PPARγ 和α 作用可以同时针对胰岛素抵抗和动脉粥样硬化性血脂异常,而 PPARβ/δ 的特性可能防止超重的发展。苯扎贝特作为所有贝特类药物,可显著降低血浆甘油三酯并增加 HDL-C 水平(但比其他主要贝特类药物强得多)。苯扎贝特可显著降低小而密的低密度脂蛋白颗粒、残粒的发生率,诱导胸主动脉和腹主动脉粥样斑块消退,并改善内皮功能。此外,苯扎贝特具有重要的纤维蛋白原相关特性和抗炎作用。在临床试验中,苯扎贝特在代谢综合征和动脉粥样硬化性血脂异常患者中对降低心血管风险非常有效。苯扎贝特与其他贝特类药物的主要区别在于对血糖水平和胰岛素抵抗的影响。与安慰剂或其他贝特类药物相比,苯扎贝特可降低血糖水平、HbA1C、胰岛素抵抗并降低 2 型糖尿病的发病率。目前,他汀类药物是治疗和预防与动脉粥样硬化相关的心血管疾病的基石。然而,尽管他汀类药物作为降低低密度脂蛋白胆固醇 (LDL-C) 的单一疗法越来越多地被使用,但在患有动脉粥样硬化性血脂异常和胰岛素抵抗的患者中,仍然存在显著的残余心血管风险,这是 2 型糖尿病和代谢综合征的典型特征。最近,人们对他汀类药物治疗患者发生糖尿病的问题表示担忧。联合苯扎贝特/他汀类药物治疗在实现全面血脂控制和降低残余心血管风险方面更有效。基于泛 PPAR 激动剂苯扎贝特对葡萄糖代谢的有益作用和预防新发糖尿病,人们可以期望通过联合他汀类药物/贝特类药物治疗策略来中和他汀类药物的不良致糖尿病作用。