UR-4, Pierre & Marie Curie University Paris VI, Paris Universitas, Paris, France.
Osteoarthritis Cartilage. 2010 Jan;18(1):106-16. doi: 10.1016/j.joca.2009.08.019. Epub 2009 Sep 15.
Although most studies have focused on the cholesterol-lowering activity of stigmasterol, other bioactivities have been ascribed to this plant sterol compound, one of which is a potential anti-inflammatory effect. To investigate the effects of stigmasterol, a plant sterol, on the inflammatory mediators and metalloproteinases produced by chondrocytes.
We used a model of newborn mouse chondrocytes and human osteoarthritis (OA) chondrocytes in primary culture stimulated with or without IL-1beta (10 ng/ml), for 18 h. Cells were pre-incubated for 48 h with stigmasterol (20 microg/ml) compared to untreated cells. We initially investigated the presence of stigmasterol in chondrocyte, compared to other phytosterols. We then assessed the role of stigmasterol on the expression of various genes involved in inflammation (IL-6) and cartilage turn-over (MMP-3, -13, ADAMTS-4, -5, type II collagen, aggrecan) by quantitative Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). Additional experiments were carried out to monitor the production of MMP-3 and prostaglandin E2 (PGE(2)) by specific immuno-enzymatic assays. We eventually looked at the role of stigmasterol on NF-kappaB activation by western blot, using an anti-IkappaBalpha antibody.
After 18 h of IL-1beta treatment, MMP-3, MMP-13, ADAMTS-4, but not ADAMTS-5 RNA expression were elevated, as well as MMP-3 and PGE(2) protein levels in mouse and human chondrocytes. Type II collagen and aggrecan mRNA levels were significatively reduced. Pre-incubation of stigmasterol to IL-1beta-treated cells significantly decreased these effects described above (significant reduction of MMP-3 mRNA in human and mouse, MMP-3 protein in mouse, MMP-13 mRNA in mouse and human, ADAMTS-4 mRNA in human, PGE(2) protein in human and mouse) Finally, stigmasterol was capable of counteracting the IL-1beta-induced NF-kappaB pathway.
This study shows that stigmasterol inhibits several pro-inflammatory and matrix degradation mediators typically involved in OA-induced cartilage degradation, at least in part through the inhibition of the NF-kappaB pathway. These promising results justify further ex vivo and in vivo investigations with stigmasterol.
虽然大多数研究都集中在豆甾醇的降低胆固醇活性上，但这种植物固醇化合物还有其他生物活性，其中之一是潜在的抗炎作用。本研究旨在探讨植物固醇 stigmasterol 对软骨细胞产生的炎症介质和金属蛋白酶的影响。
我们使用新生小鼠软骨细胞和原代培养的人骨关节炎（OA）软骨细胞模型，用或不用白介素-1β（10ng/ml）刺激 18 小时。细胞先用 stigmasterol（20μg/ml）孵育 48 小时，与未处理的细胞进行比较。我们首先比较了软骨细胞中 stigmasterol 的存在情况与其他植物固醇。然后，我们通过定量逆转录聚合酶链反应（RT-PCR）评估 stigmasterol 对涉及炎症（IL-6）和软骨代谢（MMP-3、MMP-13、ADAMTS-4、ADAMTS-5、II 型胶原、聚集蛋白聚糖）的各种基因表达的作用。通过特定的免疫酶分析进一步监测 MMP-3 和前列腺素 E2（PGE2）的产生。最后，我们使用抗 IkappaBalpha 抗体通过 Western blot 观察 stigmasterol 对 NF-kappaB 激活的作用。
在白介素-1β处理 18 小时后，MMP-3、MMP-13、ADAMTS-4 的 RNA 表达升高，同时小鼠和人软骨细胞中 MMP-3 和 PGE2 蛋白水平升高。II 型胶原和聚集蛋白聚糖的 mRNA 水平显著降低。用 stigmasterol 预孵育 IL-1β处理的细胞可显著降低上述作用（人源和鼠源 MMP-3 mRNA 显著降低，鼠源 MMP-3 蛋白、鼠源 MMP-13 mRNA、人源 ADAMTS-4 mRNA、PGE2 蛋白显著降低）。最后，stigmasterol 能够拮抗白介素-1β诱导的 NF-kappaB 通路。
本研究表明 stigmasterol 可抑制几种促炎和基质降解介质，这些介质通常参与 OA 诱导的软骨降解，至少部分通过抑制 NF-kappaB 通路。这些有希望的结果证明了用 stigmasterol 进行进一步的离体和体内研究是合理的。
