Institute of Chinese Medicine, Heilongjiang Academy of Traditional Chinese Medicine, Harbin, 150036, China; National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, 100700, China.
Institute of Chinese Medicine, Heilongjiang Academy of Traditional Chinese Medicine, Harbin, 150036, China.
J Ethnopharmacol. 2020 Feb 10;248:112349. doi: 10.1016/j.jep.2019.112349. Epub 2019 Nov 19.
Arenga pinnata (Wurmb) Merr. is a medicinal and edible plant belonging to family Palmae. The fruits of this plant were used in traditional folk medicine due to its analgesia and anti-inflammatory activities. This study aimed to investigate the analgesic and anti-inflammatory properties and the mechanism of the ethanol extract of A. pinnata (Wurmb) Merr. fruit (EAF) on different experimental models.
High-performance liquid chromatography (HPLC) was used to determine the chromatographic profile and to analyze the composition of EAF. In the acute toxicity test, all mice were orally administered EAF at a maximum dosage of 26 g/kg and were then monitored for 14 days. The potential analgesic activity of EAF was evaluated by using animal pain models, namely the acetic acid-induced writhing test and the hot plate test in mice. The underlying mechanisms of analgesia were determined by pretreating with naloxone, capsaicin and cinnamaldehyde to evaluate the involvement of the opioid system and transient receptor potential channels (TRP channels). The anti-inflammatory activity of EAF was evaluated by using the following inflammatory animal models: xylene-induced ear edema in mice and Complete Freund's adjuvant (CFA)-induced paw swelling in rats. EAF was orally administered at the doses of 1.625, 3.25 and 6.5 g/kg in mice and 1.125, 2.25 and 4.5 g/kg in rats. The underlying mechanism of the anti-inflammatory activity was determined by enzyme-linked immunosorbent assay (ELISA) kits and real time-PCR used to measure the expression levels of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), prostaglandin E2 (PGE) and cyclooxygenase-2 (COX-2). Western blot analysis was used to determine the expression levels of proteins related to the nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPK) signaling pathways in paw tissues.
Five compounds, namely (5-(hydroxymethyl) furan-2-yl) methanediol,4'-hydroxy-N-(4-hydroxy-3-methoxybenzoyl)-3',5'-dimethoxybenzamide, (+)-lyonirenisol-3a-O-β-D-glucopyranoside, (-)-lyonirenisol-3a-O-β-glucopyranoside and liquiritin, were firstly identified from A. pinnata (Wurmb) Merr. fruit by HPLC-UV analysis. In the acute toxicity test, no treatment-related toxicological signs or mortality was observed in mice administered doses up to 26 g/kg. Bodyweight was not obviously different among the treatment groups and the vehicle group. EAF significantly inhibited the pain response induced by acetic acid and increased the latency time in the hot plate test in mice. The anti-nociception effect of EAF in the formalin test was not alleviated by pretreatment with naloxone. However, the nociception induced by injection with capsaicin and cinnamaldehyde was significantly reduced by EAF. Compared with vehicle treatment, EAF significantly inhibited the formation of xylene-induced ear edema and CFA adjuvant-induced paw swelling. EAF markedly inhibited the production of IL-1β, TNF-α, PGE and IL-6 induced by CFA in paw tissues. Furthermore, the phosphorylation of IKKα, IKKβ, IκBα, p38, ERK1/2, and JNK and the nuclear translation of NF-κB p65 induced by CFA in paw tissues were significantly inhibited by EAF treatment compared with vehicle treatment.
For the first time, this study provides pharmacological evidence for the analgesic and anti-inflammatory activities of EAF and the underlying mechanism, suggesting that EAF might be a potential candidate for reducing pain and inflammatory disorders.
砂糖椰子（Wurmb）Merr. 是一种药用和食用植物，属于 Palmae 科。由于其具有镇痛和抗炎作用，该植物的果实曾在传统民间医学中使用。本研究旨在探讨砂糖椰子（Wurmb）Merr. 果实（EAF）乙醇提取物在不同实验模型中的镇痛和抗炎特性及其机制。
采用高效液相色谱法（HPLC）测定 EAF 的色谱图并分析其组成。在急性毒性试验中，所有小鼠均经口给予 EAF 最大剂量 26g/kg，然后监测 14 天。采用动物疼痛模型评估 EAF 的潜在镇痛活性，即醋酸诱导的扭体试验和小鼠热板试验。通过用纳洛酮、辣椒素和肉桂醛预处理来确定镇痛作用的潜在机制，以评估阿片系统和瞬时受体电位通道（TRP 通道）的参与情况。采用二甲苯诱导的小鼠耳肿胀和完全弗氏佐剂（CFA）诱导的大鼠足肿胀等炎症动物模型评估 EAF 的抗炎活性。EAF 以 1.625、3.25 和 6.5g/kg 的剂量在小鼠中口服给药，以 1.125、2.25 和 4.5g/kg 的剂量在大鼠中口服给药。采用酶联免疫吸附测定（ELISA）试剂盒和实时 PCR 测定白细胞介素-1β（IL-1β）、肿瘤坏死因子-α（TNF-α）、前列腺素 E2（PGE）和环氧化酶-2（COX-2）的表达水平，以确定抗炎活性的潜在机制。采用 Western blot 分析测定与核因子-κB（NF-κB）和丝裂原活化蛋白激酶（MAPK）信号通路相关的蛋白表达水平。
通过 HPLC-UV 分析，首次从砂糖椰子（Wurmb）Merr. 果实中鉴定出 5 种化合物，分别为（5-（羟甲基）呋喃-2-基）甲醇、4'-羟基-N-（4-羟基-3-甲氧基苯甲酰基）-3'、5'-二甲氧基苯甲酰胺、（+）-莱诺异醇-3a-O-β-D-吡喃葡萄糖苷、（-）-莱诺异醇-3a-O-β-吡喃葡萄糖苷和甘草素。在急性毒性试验中，给予 26g/kg 剂量的小鼠未观察到与治疗相关的毒性体征或死亡率。与对照组相比，各组小鼠体重无明显差异。EAF 显著抑制醋酸诱导的疼痛反应，增加小鼠热板试验中的潜伏期。EAF 对福尔马林试验中的抗伤害感受作用不能通过纳洛酮预处理得到缓解。然而，EAF 显著减少了辣椒素和肉桂醛引起的疼痛。与对照组相比，EAF 显著抑制二甲苯诱导的耳肿胀和 CFA 佐剂诱导的大鼠足肿胀。EAF 显著抑制 CFA 诱导的 paw 组织中 IL-1β、TNF-α、PGE 和 IL-6 的产生。此外，与对照组相比，EAF 治疗显著抑制了 CFA 诱导的 paw 组织中 IKKα、IKKβ、IκBα、p38、ERK1/2 和 JNK 的磷酸化以及 NF-κB p65 的核转位。
本研究首次为 EAF 的镇痛和抗炎活性及其潜在机制提供了药理学证据，表明 EAF 可能是减轻疼痛和炎症性疾病的潜在候选药物。
