Cardiovascular disease is a major health problem in developed countries although its incidence is relatively lower in Mediterranean countries which is partly ascribed to dietary habits. Epidemiologic evidence shows that elevated serum cholesterol, specifically low-density lipoprotein cholesterol (c-LDL), increases cardiovascular disease. Phytosterols are bioactive compounds, found in all vegetable foods, which inhibit intestinal cholesterol absorption and, therefore, have a serum cholesterollowering effect. Intestinal cholesterol absorption is a multistep process where, plant sterols and stanols may act:a) attenuating the NPC1L1 gene expression, which may result in a lower cholesterol uptake from the lumen;b) lowering the cholesterol esterification rate by the ACAT2 (acyl-CoA cholesterol acyltransferase) and, consequently, the amount of cholesterol secreted via the chylomicrons andc) upregulating the expression of ABC-transporters ABCG5 and ABCG8 in intestinal cells, which may result in an increased excretion of cholesterol by the enterocyte back in the lumen. Many clinical trials proved that commercial products enriched with phytosterols reduce cholesterol levels. Likewise, recent studies show that phytosterols present in natural food matrices are also effective and could be an important component of cardioprotective dietary patterns such as the Mediterranean diet.

中文翻译：

---

天然存在的植物甾醇对肠道胆固醇吸收和血浆水平的作用。

心血管疾病是发达国家的主要健康问题，尽管其在地中海国家的发病率相对较低，部分归因于饮食习惯。流行病学证据表明，升高的血清胆固醇，特别是低密度脂蛋白胆固醇 (c-LDL)，会增加心血管疾病。植物甾醇是生物活性化合物，存在于所有蔬菜食品中，可抑制肠道胆固醇吸收，因此具有降低血清胆固醇的作用。肠胆固醇吸收是一个多步骤过程，其中，植物甾醇和甾烷醇可作用：一个衰减NPC1L1基因表达，这可能导致从内腔中的降低胆固醇的吸收）; 乙) 通过 ACAT2（酰基辅酶 A 胆固醇酰基转移酶）降低胆固醇酯化率，从而降低通过乳糜微粒分泌的胆固醇量和c ) 上调肠道细胞中 ABC 转运蛋白 ABCG5 和 ABCG8 的表达，这可能导致肠细胞返回管腔的胆固醇排泄增加。许多临床试验证明，富含植物甾醇的商业产品可降低胆固醇水平。同样，最近的研究表明，天然食物基质中存在的植物甾醇也是有效的，可能是地中海饮食等心脏保护饮食模式的重要组成部分。