Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT 59717, USA.
Department of Pharmacognosy, Faculty of Pharmacy, Anadolu University, Eskisehir 26470, Turkey.
Molecules. 2022 Jul 31;27(15):4897. doi: 10.3390/molecules27154897.
(Pursh) Dunal is used in traditional medicine for treating various diseases; however, little is known about the immunomodulatory activity of essential oils from this plant. Thus, we isolated essential oils from the flowers (GEO) and leaves (GEO) of and evaluated the chemical composition and innate immunomodulatory activity of these essential oils. Compositional analysis of these essential oils revealed that the main components were α-pinene (24.7 and 23.2% in GEO and GEO, respectively), limonene (10.0 and 14.7%), borneol (23.4 and 16.6%), -cymen-8-ol (6.1 and 5.8%), β-pinene (4.0 and 3.8%), bornyl acetate (3.0 and 5.1%), -pinocarveol (4.2 and 3.7%), spathulenol (3.0 and 2.0%), myrtenol (2.5 and 1.7%), and terpinolene (1.7 and 2.0%). Enantiomer analysis showed that α-pinene, β-pinene, and borneol were present primarily as (-)-enantiomers (100% enantiomeric excess (ee) for (-)-α-pinene and (-)-borneol in both GEO and GEO; 82 and 78% ee for (-)-β-pinene in GEO and GEO), while limonene was present primarily as the (+)-enantiomer (94 and 96 ee in GEO and GEO). essential oils activated human neutrophils, resulting in increased [Ca] (EC = 22.3 µg/mL for GEO and 19.4 µg/mL for GEO). In addition, one of the major enantiomeric components, (-)-borneol, activated human neutrophil [Ca] (EC = 28.7 ± 2.6), whereas (+)-borneol was inactive. Since these treatments activated neutrophils, we also evaluated if they were able to down-regulate neutrophil responses to subsequent agonist activation and found that treatment with essential oils inhibited activation of these cells by the -formyl peptide receptor 1 (FPR1) agonist MLF and the FPR2 agonist WKYMVM. Likewise, (-)-borneol inhibited FPR-agonist-induced Ca influx in neutrophils. leaf and flower essential oils, as well as (-)-borneol, also inhibited MLF-induced chemotaxis of human neutrophils (IC = 4.1 ± 0.8 µg/mL, 5.0 ± 1.6 µg/mL, and 5.8 ± 1.4 µM, respectively). Thus, we identified (-)-borneol as a novel modulator of human neutrophil function.
(Pursh) Dunal 被用于传统医学治疗各种疾病；然而，关于该植物精油的免疫调节活性却知之甚少。因此，我们从花（GEO）和叶（GEO）中分离出精油，并评估了这些精油的化学成分和先天免疫调节活性。这些精油的组成分析表明，主要成分是α-蒎烯（GEO 和 GEO 中的含量分别为 24.7%和 23.2%）、柠檬烯（10.0%和 14.7%）、龙脑（23.4%和 16.6%）、β-蒎烯（4.0%和 3.8%）、乙酸龙脑酯（3.0%和 5.1%）、β-石竹烯（6.1%和 5.8%）、-松油醇（4.2%和 3.7%）、蛇麻烯醇（3.0%和 2.0%）、桃金娘醇（2.5%和 1.7%）和萜品烯醇（1.7%和 2.0%）。对映体分析表明，α-蒎烯、β-蒎烯和龙脑主要以（-）-对映体形式存在（GEO 和 GEO 中均为 100%对映体过量（ee）的（-）-α-蒎烯和（-）-龙脑；GEO 和 GEO 中为 82%和 78%ee 的（-）-β-蒎烯），而柠檬烯主要以（+）-对映体形式存在（GEO 和 GEO 中均为 94%和 96%ee）。该植物精油激活了人中性粒细胞，导致[Ca]增加（GEO 的 EC = 22.3µg/mL，GEO 的 EC = 19.4µg/mL）。此外，主要的对映体成分之一（-）-龙脑激活了人中性粒细胞的[Ca]（EC = 28.7±2.6），而（+）-龙脑则没有活性。由于这些处理激活了中性粒细胞，我们还评估了它们是否能够下调中性粒细胞对随后激动剂激活的反应，发现用该植物精油处理可抑制中性粒细胞被-甲酰肽受体 1（FPR1）激动剂 MLF 和 FPR2 激动剂 WKYMVM 激活。同样，（-）-龙脑抑制了 FPR-激动剂诱导的中性粒细胞内 Ca 流入。该植物的叶和花精油以及（-）-龙脑也抑制了 MLF 诱导的人中性粒细胞趋化性（IC = 4.1±0.8µg/mL、5.0±1.6µg/mL 和 5.8±1.4µM）。因此，我们确定（-）-龙脑是一种新型人中性粒细胞功能调节剂。
