Department of Pharmacology, School of Medicine, AJA University of Medical Sciences, Tehran, Iran.
Department of Pathology, Imam Hospital, Tehran University of Medical Sciences, Tehran, Iran.
Inflammopharmacology. 2019 Dec;27(6):1275-1283. doi: 10.1007/s10787-019-00583-8. Epub 2019 Mar 21.
The aim of the present study was to evaluate the anti-inflammatory effect of thymol in acetic acid-induced rat colitis through inhibiting the NF-κB signaling pathway.
Colitis was induced by intra-rectal administration of 2 mL of diluted acetic acid (4%) solution using a flexible plastic rubber catheter in Wistar rats. Colitis was induced on the first day and all treatments were applied 5 days after the induction of colitis. Thymol was dissolved in 0.2% tween 80 in saline and administered orally at doses of 10, 30, and 100 mg/kg per day. Macroscopic and histopathologic investigations were done. The expression of myeloperoxidase (MPO) and tumor necrosis factor-α (TNF-α) was determined by immunohistochemistry (IHC) assay. The protein expression level of pNF-κB p65 was measured by the Western blot technique.
Treatment with thymol reduced mucosal and histological damages compared to the acetic acid group. Our results showed that thymol markedly inhibited the production of MPO and TNF-α in the colon tissue of the acetic acid-induced group. In addition, thymol decreased acetic acid-induced up-regulation of pNFκB p65 protein.
The results of our study suggest that thymol exerts an anti-inflammatory effect in acetic acid-induced rat colitis by inhibiting the NF-κB signaling pathway and downregulating TNF-α and MPO expressions.
本研究旨在通过抑制 NF-κB 信号通路来评估百里香酚在乙酸诱导的大鼠结肠炎中的抗炎作用。
通过使用柔性塑料橡胶导管将 2 毫升稀释的乙酸（4%）溶液经直肠内给药在 Wistar 大鼠中诱导结肠炎。在诱导结肠炎的第一天诱导结肠炎，并且在诱导结肠炎后 5 天应用所有治疗。百里香酚溶解在生理盐水中的 0.2%吐温 80 中，并以 10、30 和 100mg/kg/天的剂量口服给予。进行宏观和组织病理学研究。通过免疫组织化学（IHC）测定测定髓过氧化物酶（MPO）和肿瘤坏死因子-α（TNF-α）的表达。通过 Western blot 技术测量 pNF-κB p65 的蛋白表达水平。
与乙酸组相比，百里香酚治疗减轻了黏膜和组织损伤。我们的结果表明，百里香酚可显著抑制乙酸诱导组结肠组织中 MPO 和 TNF-α的产生。此外，百里香酚降低了乙酸诱导的 pNFκB p65 蛋白的上调。
我们的研究结果表明，百里香酚通过抑制 NF-κB 信号通路并下调 TNF-α和 MPO 的表达，在乙酸诱导的大鼠结肠炎中发挥抗炎作用。
