Department of Pharmacognosy, Faculty of Pharmacy, Cairo University, Kasr El-Aini St., Cairo 11562, Egypt.
Department of Pharmacology, Faculty of Pharmacy, Cairo University, Kasr El-Aini St., Cairo 11562, Egypt.
Biomed Pharmacother. 2020 Aug;128:110303. doi: 10.1016/j.biopha.2020.110303. Epub 2020 May 29.
Hibiscus sabdariffa L. (Malvaceae) is one of the well-known traditionally used remedy worldwide. It exhibited numerous pharmacological properties including antioxidant, antidepressant, sedative, anti-inflammatory, antiproliferative, antimicrobial and neuroprotective activities. The aim of this study is to highlight the mechanisms underlying the neuroprotective effects of anthocyanin-enriched extracts of two Hibiscus varieties (white and red calyces) in the management of Alzheimer's disease (AD) in addition to their metabolic profiling. The anthocyanin contents were determined quantitatively using the pH-differential technique and qualitatively by LC/MS/MS. The extracts were tested in vitro for their antioxidant potential as well as acetylcholinesterase inhibition activity and both showed promising activities. The LC/MS/MS analysis allowed the tentative identification of 26 and 24 metabolites in red and white calyces, respectively, represented by anthocyanins, flavonoids, aliphatic and phenolic acids. In vivo, streptozotocin induced AD in mice model was established and Hibiscus extracts were tested at a dose of 200 mg kg compared to celecoxib (30 mg/kg). Histopathology of cerebral cortex and hippocampus, immunohistochemistry for tau- protein and caspase-3 with behavioral tests and measurement of several biochemical parameters were done. Hibiscus prevented memory impairment, and this could be attributed to the amelioration of STZ-induced neuroinflammation and amyloidogenesis. Consequently, Hibiscus represents a promising safe agent that can be repurposed for AD through exerting anti-inflammatory, anti-acetylcholinesterase, antioxidant, and anti-amyloidogenic activities.
洛神花（锦葵科）是一种在世界范围内被广泛应用的传统草药。它具有多种药理活性，包括抗氧化、抗抑郁、镇静、抗炎、抗增殖、抗菌和神经保护作用。本研究旨在强调两种洛神花（白萼和红萼）花色苷丰富提取物在阿尔茨海默病（AD）管理中的神经保护作用机制，以及它们的代谢特征。花色苷含量采用 pH 差示法进行定量分析，并用 LC/MS/MS 进行定性分析。提取物在体外进行抗氧化潜力和乙酰胆碱酯酶抑制活性测试，结果均显示出良好的活性。LC/MS/MS 分析分别鉴定出红萼和白萼花色苷提取物中的 26 种和 24 种代谢物，分别由花色苷、类黄酮、脂肪族和酚酸组成。在体内，采用链脲佐菌素（STZ）诱导建立 AD 小鼠模型，用两种花色苷提取物（剂量为 200mg/kg）与塞来昔布（30mg/kg）进行对比。对大脑皮质和海马体进行组织病理学检查，用 tau 蛋白和 caspase-3 进行免疫组织化学染色，同时进行行为学测试和多种生化参数的测量。结果表明，洛神花提取物可预防记忆障碍，这可能归因于其改善了 STZ 诱导的神经炎症和淀粉样蛋白形成。因此，洛神花作为一种有前途的安全药物，通过发挥抗炎、抗乙酰胆碱酯酶、抗氧化和抗淀粉样蛋白形成作用，可以被重新用于 AD 的治疗。
