Myricetin

Myricetin is a natural flavonoid commonly found in plants, possessing antioxidant, anti-inflammatory, and anti-tumor activities, and acts as a novel inhibitor of mitogen-activated protein kinase kinase (MEK1) and neoplastic transformation in JB6 P+ mouse epidermal cells^[1,2]. Myricetin is commonly used in the treatment and research of various types of tumors, diabetes, Alzheimer's disease, and inflammatory diseases^[3].

In vitro, pre-incubation of human colon cancer Hct116 cells with myricetin (50μM) for 4h, followed by induction of oxidative stress with 500μM H₂O₂ for 1h, significantly reduced intracellular reactive oxygen species (ROS) accumulation to 46.1% ± 9.1% of the control group^[4]. Pre-treatment of JB6 P+ cells with myricetin (2.5-20μM) for 1h, followed by UVB irradiation (0.05 J/cm²), inhibited UVB-induced cyclooxygenase-2 (COX-2) protein expression and promoter activity in a dose-dependent manner^[5].

In vivo, oral administration of myricetin (50mg/kg/day) to ICR mice for 3 consecutive weeks significantly enhanced their aerobic capacity and improved motor coordination^[6]. Intravenous administration of myricetin (1mg/kg/time; 3 times daily) to high-fructose diet-induced insulin-resistant Wistar rats for 14 days significantly reduced elevated plasma blood glucose and triglyceride levels^[7]. Oral gavage of myricetin (150mg/kg/day) to high-fat diet (HFD)-induced obese C57BL/6 mice for 10 weeks significantly reduced body weight and decreased serum glucose and triglyceride levels^[8].

References:
[1] IMRAN M, SAEED F, HUSSAIN G, et al. Myricetin: A comprehensive review on its biological potentials[J]. Food science & nutrition, 2021, 9(10): 5854-5868.
[2] LEE K W, KANG N J, ROGOZIN E A, et al. Myricetin is a novel natural inhibitor of neoplastic cell transformation and MEK1[J]. Carcinogenesis, 2007, 28(9): 1918-1927.
[3] SONG X, TAN L, WANG M, et al. Myricetin: A review of the most recent research[J]. Biomedicine & Pharmacotherapy, 2021, 134: 111017.
[4] BüCHTER C, ACKERMANN D, HAVERMANN S, et al. Myricetin-mediated lifespan extension in Caenorhabditis elegans is modulated by DAF-16[J]. International journal of molecular sciences, 2013, 14(6): 11895-11914.
[5] JUNG S K, LEE K W, BYUN S, et al. Myricetin suppresses UVB-induced skin cancer by targeting Fyn[J]. Cancer research, 2008, 68(14): 6021-6029.
[6] JUNG H Y, LEE D, RYU H G, et al. Myricetin improves endurance capacity and mitochondrial density by activating SIRT1 and PGC-1α[J]. Scientific reports, 2017, 7: 6237.
[7] LIU I M, TZENG T F, LIOU S S, et al. Myricetin, a naturally occurring flavonol, ameliorates insulin resistance induced by a high-fructose diet in rats[J]. Life sciences, 2007, 81(21-22): 1479-1488.
[8] SU H, FENG L, ZHENG X, et al. Myricetin protects against diet-induced obesity and ameliorates oxidative stress in C57BL/6 mice[J]. Journal of Zhejiang University-Science B, 2016, 17(6): 437-446.

Myricetin是一种常见于植物且具有抗氧化、抗炎和抗肿瘤活性的天然黄酮类化合物，是丝裂原活化蛋白激酶激酶（MEK1）和 JB6 P+小鼠表皮细胞转化的新型抑制剂^[1,2]。Myricetin通常用于不同类型肿瘤、糖尿病、阿尔兹海默症和炎症性疾病等的治疗和研究^[3]。

在体外，myricetin（50μM）预孵育人结肠癌Hct116细胞4h，后施加500μM H₂O₂诱导氧化应激1h，显著降低了细胞内活性氧（ROS）积累至对照组的46.1% ± 9.1%^[4]。Myricetin（2.5-20μM）预处理JB6 P+细胞1h，后照射UVB（0.05 J/cm²），以剂量依赖性方式抑制了UVB诱导的环氧化酶-2（COX-2）蛋白表达和启动子活性^[5]。

在体内，myricetin（50mg/kg/day）通过口服给药ICR小鼠连续3周，显著增强了小鼠的有氧能力并改善了运动协调性^[6]。Myricetin（1mg/kg/time; 3 times daily）通过静脉注射处理高果糖饮食诱导的胰岛素抵抗Wistar大鼠14天，可显著降低大鼠血浆中过高的血糖和甘油三酯水平^[7]。Myricetin（150mg/kg/day）通过口服灌胃给药高脂饮食（HFD）诱导的肥胖C57BL/6小鼠10周，显著减轻了小鼠的体重并降低了血清中葡萄糖和甘油三酯的水平^[8]。