Department of Pharmacology, Wroclaw Medical University, Mikulicza-Radeckiego 2, 50-345, Wrocław, Poland.
Inflammopharmacology. 2018 Apr;26(2):571-581. doi: 10.1007/s10787-017-0337-0. Epub 2017 Mar 24.
Inflammatory bowel disease (IBD) [including Crohn's disease (CD) and ulcerative colitis (UC)] constitutes an important clinical problem. The pathogenesis of IBD remains unclear. It is believed that immune dysfunction, inflammatory mediators and oxidative damage play crucial roles in development of IBD. The condition is clinically associated with symptoms ranging from mild to severe during relapses, depending on the affected segment of the gastrointestinal tract. Bloody diarrhea with mucus, abdominal pain, weight loss and anemia are initial symptoms of both CD and UC. Differences between diseases become more evident in time, along with the development of intestinal and extraintestinal complications. Mangiferin (1,3,6,7-tetrahydroxyxanthone-C-2-β-D-glucoside), a natural polyphenol in plants, exerts antioxidant and anti-inflammatory effects making it an interesting option for the treatment of inflammatory pathologies associated with oxidative stress in humans, such as IBD.
The aim of the current study was to elucidate the impact of mangiferin on colon tissues in 2,4,6-trinitrobenzensulfonic acid (TNBS)-induced colitis in rats.
Mangiferin was obtained from Belamcanda chinensis rhizomes by a multistage process. Groups of rats were pre-treated with 10, 30 or 100 mg/kg of mangiferin, or with distilled water administered intragastrically for 16 days. An ethanol solution of TNBS or saline was given rectally on the day 15 of the experiment. The experiment was terminated on the day 17. The colon was removed, cleaned, weighed and examined macro- and microscopically. Determination of tumor necrosis factor α (TNF-α), interleukin 17 (IL-17), malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity were performed spectrophotometrically in homogenates of colon tissues.
Rats in the TNBS group developed symptoms of colitis, including: body weight loss, colon mass index increase and damage of intestinal tissues with concomitant increase in TNF-α, IL-17, MDA levels and decreased SOD activity. In non-TNBS-treated rats mangiferin did not cause any changes of studied parameters. Pre-treatment with mangiferin exerted a protective effect, reducing the intensity of damage caused by TNBS. Mangiferin at the doses of 30 and 100 mg/kg reduced the macro- and microscopic damage score and the MDA level in colon tissues. Only at the dose of 100 mg/kg, mangiferin decreased TNF-α and IL-17 concentrations, and SOD activity in colon tissues.
Mangiferin attenuates inflammatory changes of colon tissues in experimental, TNBS-induced colitis in rats. Protective effect exerted by mangiferin depends primarily on its anti-inflammatory activity and secondarily on its antioxidant properties.
炎症性肠病（IBD）[包括克罗恩病（CD）和溃疡性结肠炎（UC）]是一个重要的临床问题。IBD 的发病机制仍不清楚。据信，免疫功能障碍、炎症介质和氧化损伤在 IBD 的发展中起着至关重要的作用。这种疾病的临床症状从轻度到重度不等，具体取决于胃肠道受影响的部位。CD 和 UC 的初始症状均为血性腹泻伴黏液、腹痛、体重减轻和贫血。随着疾病的发展，肠道和肠道外并发症的出现，疾病之间的差异变得更加明显。芒果苷（1,3,6,7-四羟基-2-β-D-葡萄糖基黄烷酮），一种植物中的天然多酚，具有抗氧化和抗炎作用，使其成为治疗人类与氧化应激相关的炎症性疾病的一个有趣选择，如 IBD。
本研究旨在探讨芒果苷对 2,4,6-三硝基苯磺酸（TNBS）诱导的大鼠结肠炎结肠组织的影响。
芒果苷从射干根茎中通过多步过程获得。各组大鼠分别用 10、30 或 100mg/kg 的芒果苷预处理，或用灌胃给予蒸馏水 16 天。在实验的第 15 天，直肠给予乙醇溶液的 TNBS 或生理盐水。实验于第 17 天结束。取出结肠，清洗，称重并进行宏观和微观检查。用分光光度法测定结肠组织匀浆中肿瘤坏死因子-α（TNF-α）、白细胞介素 17（IL-17）、丙二醛（MDA）水平和超氧化物歧化酶（SOD）活性。
TNBS 组大鼠出现结肠炎症状，包括：体重减轻、结肠质量指数增加和肠道组织损伤，同时 TNF-α、IL-17、MDA 水平升高，SOD 活性降低。在未用 TNBS 处理的大鼠中，芒果苷未引起任何研究参数的变化。芒果苷预处理具有保护作用，可减轻 TNBS 引起的损伤程度。芒果苷在 30 和 100mg/kg 剂量下可降低结肠组织的宏观和微观损伤评分和 MDA 水平。只有在 100mg/kg 剂量下，芒果苷才降低结肠组织中的 TNF-α 和 IL-17 浓度和 SOD 活性。
芒果苷可减轻实验性、TNBS 诱导的大鼠结肠炎结肠组织的炎症变化。芒果苷的保护作用主要取决于其抗炎活性，其次取决于其抗氧化特性。
