Post-Graduate Program in Pharmaceutical Sciences, Federal University of Pernambuco, Recife, PE, Brazil; Pharmacognosy Laboratory, Department of Pharmaceutical Sciences, Federal University of Pernambuco, Recife, PE, Brazil.
Laboratório de Bioquímica de Proteínas, Departamento de Bioquímica, Universidade Federal de Pernambuco, Avenida Professor Moraes Rego, s/n, Cidade Universitária, 50670-420, Recife, PE, Brazil.
J Ethnopharmacol. 2022 Oct 5;296:115508. doi: 10.1016/j.jep.2022.115508. Epub 2022 Jun 29.
Eugenia uniflora (Myrtaceae) is a species native to Brazil and has a traditional use in the treatment of inflammation.
To evaluate the anti-inflammatory and antinociceptive effects, and the involvement of opioid receptors in the antinociceptive activity of extract and fractions from Eugenia uniflora leaves.
TLC and HPLC were used to characterize the spray-dried extract (SDE) and fractions. In the in vivo assays, Swiss (Mus musculus) mice were used. Carrageenan-induced hind-paw edema and carrageenan-induced peritonitis models were used to determine the anti-inflammatory effect of the extract (50, 100, or 200 mg/kg). Acetic acid-induced writhing, tail-flick, and formalin tests were used to determine the antinociceptive effect of the extract (50, 100, or 200 mg/kg). The aqueous (AqF) and ethyl acetate (EAF) fractions (6.25, 12.5, and 25 mg/kg) were then combined with naloxone to evaluate the involvement of opioid receptors in the antinociceptive activity.
In this work, the TLC and HPLC analysis evidenced the enrichment of EAF, which higher concentration of gallic acid (5.29 ± 0.0004 %w/w), and ellagic acid (1.28 ± 0.0002 %w/w) and mainly myricitrin (8.64 ± 0.0002 %w/w). The extract decreased the number of total leukocytes and neutrophils in the peritoneal cavity (p < 0.05), at doses of 100 and 200 mg/kg and showed significant inhibition in the increase of paw edema volume (p < 0.05). The treatment per oral route (doses of 50, 100, and 200 mg/kg) significantly reduced the nociceptive response in acetic acid-induced abdominal writhing (p < 0.05). The effect of the extract on the tail-flick test showed a significant increase in latency time of animals treated at doses of 200 and 100 mg/kg (p < 0.05). The extract and ethyl acetate fraction reduced the nociceptive effect in both phases of formalin at all tested doses. The naloxone reversed the antinociceptive effect of EAF, suggesting that opioid receptors are involved in mediating the antinociceptive activity of EAF of E. uniflora in the formalin test.
The current study demonstrates the anti-inflammatory and analgesic activities of water: ethanol: propylene glycol spray-dried extract from E. uniflora leaves using in vivo pharmacological models in mice. Our findings suggest that spray-dried extract and ethyl acetate fraction exhibit peripheral and central antinociceptive activity with the involvement of opioid receptors that may be related to the presence of flavonoids, mainly myricitrin.
Eugenia uniflora（桃金娘科）是一种原产于巴西的物种，具有治疗炎症的传统用途。
评估 Eugenia uniflora 叶提取物和馏分的抗炎和镇痛作用，以及阿片受体在镇痛活性中的参与。
采用 TLC 和 HPLC 对喷雾干燥提取物（SDE）和馏分进行了表征。在体内试验中，使用瑞士（Mus musculus）小鼠。使用角叉菜胶诱导的后爪水肿和角叉菜胶诱导的腹膜炎模型来确定提取物（50、100 或 200mg/kg）的抗炎作用。使用醋酸诱导的扭体、尾部闪烁和福马林试验来确定提取物（50、100 或 200mg/kg）的镇痛作用。然后将水（AqF）和乙酸乙酯（EAF）馏分（6.25、12.5 和 25mg/kg）与纳洛酮联合使用，以评估阿片受体在镇痛活性中的参与。
在这项工作中，TLC 和 HPLC 分析证明了 EAF 的富集，其更高浓度的没食子酸（5.29±0.0004%w/w）和鞣花酸（1.28±0.0002%w/w）和主要的杨梅素（8.64±0.0002%w/w）。提取物减少了腹腔内总白细胞和中性粒细胞的数量（p<0.05），在 100 和 200mg/kg 剂量下，对爪水肿体积的增加有显著抑制作用（p<0.05）。口服给药（50、100 和 200mg/kg 剂量）显著减少了醋酸诱导的腹部扭体反应中的疼痛反应（p<0.05）。提取物对尾部闪烁试验的影响表明，在 200 和 100mg/kg 剂量下，动物的潜伏期时间明显增加（p<0.05）。提取物和乙酸乙酯馏分在所有测试剂量下均降低了福马林试验中疼痛的作用。纳洛酮逆转了 EAF 的镇痛作用，表明阿片受体参与介导 E. uniflora 叶水：乙醇：丙二醇喷雾干燥提取物在福马林试验中的镇痛活性。
本研究使用小鼠体内药理学模型证明了 Eugenia uniflora 叶的水：乙醇：丙二醇喷雾干燥提取物的抗炎和镇痛活性。我们的研究结果表明，喷雾干燥提取物和乙酸乙酯馏分表现出外周和中枢镇痛活性，涉及阿片受体，这可能与类黄酮的存在有关，主要是杨梅素。
