Dept Plant Agriculture, University of Guelph, Ontario, Canada.
BMC Complement Altern Med. 2010 May 11;10:19. doi: 10.1186/1472-6882-10-19.
A variety of mint [Mentha spicata] has been bred which over-expresses Rosmarinic acid (RA) by approximately 20-fold. RA has demonstrated significant anti-inflammatory activity in vitro and in small rodents; thus it was hypothesized that this plant would demonstrate significant anti-inflammatory activity in vitro. The objectives of this study were: a) to develop an in vitro extraction procedure which mimics digestion and hepatic metabolism, b) to compare anti-inflammatory properties of High-Rosmarinic-Acid Mentha spicata (HRAM) with wild-type control M. spicata (CM), and c) to quantify the relative contributions of RA and three of its hepatic metabolites [ferulic acid (FA), caffeic acid (CA), coumaric acid (CO)] to anti-inflammatory activity of HRAM.
HRAM and CM were incubated in simulated gastric and intestinal fluid, liver microsomes (from male rat) and NADPH. Concentrations of RA, CA, CO, and FA in simulated digest of HRAM (HRAMsim) and CM (CMsim) were determined (HPLC) and compared with concentrations in aqueous extracts of HRAM and CM. Cartilage explants (porcine) were cultured with LPS (0 or 3 microg/mL) and test article [HRAMsim (0, 8, 40, 80, 240, or 400 microg/mL), or CMsim (0, 1, 5 or 10 mg/mL), or RA (0.640 microg/mL), or CA (0.384 microg/mL), or CO (0.057 microg/mL) or FA (0.038 microg/mL)] for 96 h. Media samples were analyzed for prostaglandin E2 (PGE2), interleukin 1beta (IL-1), glycosaminoglycan (GAG), nitric oxide (NO) and cell viability (differential live-dead cell staining).
RA concentration of HRAMsim and CMsim was 49.3 and 0.4 microg/mL, respectively. CA, FA and CO were identified in HRAMsim but not in aqueous extract of HRAM. HRAMsim (> or = 8 microg/mL) inhibited LPS-induced PGE2 and NO; HRAMsim (> or = 80 microg/mL) inhibited LPS-induced GAG release. RA inhibited LPS-induced GAG release. No anti-inflammatory or chondroprotective effects of RA metabolites on cartilage explants were identified.
Our biological extraction procedure produces a substance which is similar in composition to post-hepatic products. HRAMsim is an effective inhibitor of LPS-induced inflammation in cartilage explants, and effects are primarily independent of RA. Further research is needed to identify bioactive phytochemical(s) in HRAMsim.
已经培育出了多种薄荷（Mentha spicata），这些薄荷通过大约 20 倍的方式过度表达迷迭香酸（RA）。RA 在体外和小型啮齿动物中表现出显著的抗炎活性；因此，人们假设这种植物在体外会表现出显著的抗炎活性。本研究的目的是：a）开发一种模拟消化和肝代谢的体外提取程序，b）比较高迷迭香酸薄荷（HRAM）与野生型对照薄荷（CM）的抗炎特性，c）定量 RA 及其三种肝代谢产物[阿魏酸（FA）、咖啡酸（CA）、香豆酸（CO）]对 HRAM 抗炎活性的相对贡献。
将 HRAM 和 CM 孵育在模拟胃液和肠液、肝微粒体（来自雄性大鼠）和 NADPH 中。测定 HRAM 模拟消化物（HRAMsim）和 CM 模拟消化物（CMsim）中 RA、CA、CO 和 FA 的浓度（HPLC），并与 HRAM 和 CM 的水溶液提取物中的浓度进行比较。用 LPS（0 或 3 μg/mL）和测试物质[HRAMsim（0、8、40、80、240 或 400 μg/mL）或 CMsim（0、1、5 或 10 mg/mL）或 RA（0.640 μg/mL）或 CA（0.384 μg/mL）或 CO（0.057 μg/mL）或 FA（0.038 μg/mL）]培养软骨外植体（猪）96 小时。分析培养基样品中前列腺素 E2（PGE2）、白细胞介素 1β（IL-1）、糖胺聚糖（GAG）、一氧化氮（NO）和细胞活力（差示死活细胞染色）。
HRAMsim 和 CMsim 的 RA 浓度分别为 49.3 和 0.4 μg/mL。在 HRAMsim 中鉴定出 CA、FA 和 CO，但在 HRAM 的水溶液提取物中未鉴定出。HRAMsim（≥8 μg/mL）抑制 LPS 诱导的 PGE2 和 NO；HRAMsim（≥80 μg/mL）抑制 LPS 诱导的 GAG 释放。RA 抑制 LPS 诱导的 GAG 释放。未发现 RA 代谢物对软骨外植体有抗炎或软骨保护作用。
我们的生物提取程序产生的物质在组成上类似于肝后产物。HRAMsim 是软骨外植体中 LPS 诱导炎症的有效抑制剂，其作用主要与 RA 无关。需要进一步研究以鉴定 HRAMsim 中的生物活性植物化学物质。
