Lim Hyun Jung, Prajapati Ritu, Seong Su Hui, Jung Hyun Ah, Choi Jae Sue
Institute of Fisheries Sciences, Pukyong National University, Busan 46041, Republic of Korea.
Department of Food and Life Science, Pukyong National University, Busan 48513, Republic of Korea.
ACS Omega. 2023 Feb 10;8(7):6538-6549. doi: 10.1021/acsomega.2c06916. eCollection 2023 Feb 21.
Aglycone- and glycoside-derived forms of flavonoids exist broadly in plants and foods such as fruits, vegetables, and peanuts. However, most studies focus on the bioavailability of flavonoid aglycone rather than its glycosylated form. Kaempferol-3--β-d-glucuronate (K3G) is a natural flavonoid glycoside obtained from various plants that have several biological activities, including antioxidant and anti-inflammatory effects. However, the molecular mechanism related to the antioxidant and antineuroinflammatory activity of K3G has not yet been demonstrated. The present study was designed to demonstrate the antioxidant and antineuroinflammatory effect of K3G against lipopolysaccharide (LPS)-stimulated BV2 microglial cells and to evaluate the underlying mechanism. Cell viability was determined by MTT assay. The inhibition rate of reactive oxygen species (ROS) and the production of pro-inflammatory mediators and cytokines were measured by DCF-DA assay, Griess assay, enzyme-linked immunosorbent assay (ELISA), and western blotting. K3G inhibited the LPS-induced release of nitric oxide, interleukin (IL)-6, and tumor necrosis factor-α (TNF-α) as well as the expression of prostaglandin E synthase 2. Additionally, K3G reduced the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and nuclear factor-kappa B (NF-κB) related proteins. Mechanistic studies found that K3G downregulated phosphorylated mitogen-activated protein kinases (MAPKs) and upregulated the Nrf2/HO-1 signaling cascade. In this study, we demonstrated the effects of K3G on antineuroinflammation by inactivating phosphorylation of MPAKs and on antioxidants by upregulating the Nrf2/HO-1 signaling pathway through decreasing ROS in LPS-stimulated BV2 cells.
黄酮类化合物的苷元形式和糖苷衍生形式广泛存在于植物和水果、蔬菜及花生等食物中。然而，大多数研究关注的是黄酮苷元的生物利用度，而非其糖基化形式。山奈酚 -3-β -d-葡糖醛酸苷（K3G）是一种从多种植物中获得的天然黄酮糖苷，具有多种生物活性，包括抗氧化和抗炎作用。然而，与K3G的抗氧化和抗神经炎症活性相关的分子机制尚未得到证实。本研究旨在证明K3G对脂多糖（LPS）刺激的BV2小胶质细胞的抗氧化和抗神经炎症作用，并评估其潜在机制。通过MTT法测定细胞活力。采用DCF - DA法、Griess法、酶联免疫吸附测定（ELISA）和蛋白质印迹法测定活性氧（ROS）的抑制率以及促炎介质和细胞因子的产生。K3G抑制了LPS诱导的一氧化氮、白细胞介素（IL）-6和肿瘤坏死因子-α（TNF-α）的释放以及前列腺素E合酶2的表达。此外，K3G降低了诱导型一氧化氮合酶（iNOS）、环氧化酶-2（COX-2）和核因子-κB（NF-κB）相关蛋白的表达。机制研究发现，K3G下调磷酸化丝裂原活化蛋白激酶（MAPKs）并上调Nrf2/HO-1信号级联反应。在本研究中，我们证明了K3G通过使MPAKs磷酸化失活对抗神经炎症的作用，以及通过上调Nrf2/HO-1信号通路并降低LPS刺激的BV2细胞中的ROS对抗氧化的作用。
