Department of Pharmacology, School of Pharmacy, University of Seville, C/Profesor García González 2, 41012 Seville, Spain.
Phytomedicine. 2012 Sep 15;19(12):1072-6. doi: 10.1016/j.phymed.2012.06.008. Epub 2012 Jul 21.
Evening Primrose oil is a natural product extracted by cold-pressed from Oenothera biennis L. seeds. The unsaponifiable matter of this oil is an important source of interesting minor compounds, like long-chain fatty alcohols, sterols and tocopherols. In the present study, sterols were isolated from the unsaponifiable matter of Evening Primrose oil, and the composition was identified and quantified by GC and GC-MS. The major components of sterols fraction were β-Sitosterol and campesterol. We investigated the ability of sterols from Evening Primrose oil to inhibit the release of different proinflammatory mediators in vitro by murine peritoneal macrophages stimulated with lipopolysaccharide. Sterols significantly and dose-dependently decreased nitric oxide production. Western blot analysis showed that nitric oxide reduction was a consequence of the inhibition of inducible nitric oxide synthetase expression. Sterols also reduced tumor necrosis factor-α, interleukine 1β and tromboxane B₂. However, sterols did not reduce prostaglandin E₂. The reduction of eicosanoid release was related to the inhibition of cyclooxygenase-2 expression. These results showed that sterols may have a protective effect on some mediators involved in inflammatory damage development, suggesting its potential value as a putative functional component of Evening Primrose oil.
月见草油是一种天然产物，通过冷榨从月见草种子中提取。这种油的不可皂化物是有趣的少量化合物的重要来源，如长链脂肪醇、甾醇和生育酚。在本研究中，从月见草油的不可皂化物中分离出甾醇，并通过 GC 和 GC-MS 对其组成进行了鉴定和定量。甾醇馏分的主要成分是 β-谷甾醇和菜油甾醇。我们研究了甾醇抑制脂多糖刺激的小鼠腹腔巨噬细胞释放不同促炎介质的能力。甾醇显著且剂量依赖性地降低一氧化氮的产生。Western blot 分析表明，一氧化氮的减少是诱导型一氧化氮合酶表达抑制的结果。甾醇还降低了肿瘤坏死因子-α、白细胞介素 1β 和血栓素 B₂。然而，甾醇并没有降低前列腺素 E₂。类花生酸释放的减少与环加氧酶-2 表达的抑制有关。这些结果表明，甾醇可能对一些参与炎症损伤发展的介质具有保护作用，这表明其作为月见草油潜在功能成分的潜在价值。
