Tianjin Key Laboratory of Ophthalmology and Visual Science, Tianjin Eye Institute, Tianjin Eye Hospital, Tianjin 300020, China; Clinical College of Ophthalmology, Tianjin Medical University, Tianjin 300020, China; Nankai University Affiliated Eye Hospital, Nankai University, Tianjin 300020, China; Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics, School of Pharmacy, Tianjin Medical University, Tianjin 300070, China.
Tianjin Key Laboratory of Ophthalmology and Visual Science, Tianjin Eye Institute, Tianjin Eye Hospital, Tianjin 300020, China; Clinical College of Ophthalmology, Tianjin Medical University, Tianjin 300020, China; Nankai University Affiliated Eye Hospital, Nankai University, Tianjin 300020, China.
Biomed Pharmacother. 2018 May;101:87-93. doi: 10.1016/j.biopha.2018.02.054. Epub 2018 Feb 23.
Chronic inflammation in retinal pigment epithelial (RPE) cells is related to the pathogenesis of retinal inflammatory blind causing diseases such as age-related macular degeneration (AMD) and diabetic retinopathy (DR). Nepetin, a natural flavonoid compound, has shown potent anti-inflammatory activities but has not been studied on ocular resident cells yet. Here, we assess the ability of Nepetin to alleviate the inflammatory responses of ARPE-19 cells induced by interleukin (IL)-1β.
The secretion and mRNA expression of inflammatory cytokines IL-6, IL-8 and monocyte chemoattractant protein-1 (MCP-1) induced by IL-1β are measured by enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (RT-PCR) respectively. To clarify the underlying action mechanism, we examine the effect of Nepetin on activation of nuclear factor of kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways using Western blot.
Nepetin can significantly decrease the three inflammatory mediators at both protein and mRNA level in a dose-dependent manner. Western blot results show that Nepetin can decrease the nuclear translocation of p65 through suppressing phosphorylation of inhibitor of nuclear factor kappa B (IκB) and IκB kinase (IKK). Also, Nepetin can decrease the phosphorylation of extracellular signal-regulated kinases (ERK) 1/2, c-Jun N-terminal kinase (JNK) and p38 MAPK.
Taken together, Nepetin abolishes IL-1β-induced IL-6, IL-8 and MCP-1 secretion and mRNA expression by repressing the activation of NF-κB and MAPKs. These results indicate that Nepetin shows potential to be used for prevention and treatment of inflammatory retinal diseases or as a lead compound.
视网膜色素上皮 (RPE) 细胞的慢性炎症与年龄相关性黄斑变性 (AMD) 和糖尿病性视网膜病变 (DR) 等致盲性视网膜炎症性疾病的发病机制有关。山奈酚是一种天然类黄酮化合物，具有很强的抗炎活性，但尚未在眼部驻留细胞中进行研究。在这里，我们评估山奈酚减轻白细胞介素 (IL)-1β诱导的 ARPE-19 细胞炎症反应的能力。
通过酶联免疫吸附试验 (ELISA) 和实时聚合酶链反应 (RT-PCR) 分别测量 IL-1β诱导的炎症细胞因子 IL-6、IL-8 和单核细胞趋化蛋白-1 (MCP-1) 的分泌和 mRNA 表达。为了阐明潜在的作用机制，我们使用 Western blot 检查山奈酚对核因子 κB (NF-κB) 和丝裂原活化蛋白激酶 (MAPK) 信号通路激活的影响。
山奈酚可显著降低三种炎症介质的蛋白和 mRNA 水平，呈剂量依赖性。Western blot 结果表明，山奈酚通过抑制核因子κB 抑制剂 (IκB) 和 IκB 激酶 (IKK) 的磷酸化来减少 p65 的核易位。此外，山奈酚还可以减少细胞外信号调节激酶 (ERK) 1/2、c-Jun N-末端激酶 (JNK) 和 p38 MAPK 的磷酸化。
综上所述，山奈酚通过抑制 NF-κB 和 MAPKs 的激活，消除了 IL-1β 诱导的 IL-6、IL-8 和 MCP-1 的分泌和 mRNA 表达。这些结果表明，山奈酚具有用于预防和治疗炎症性视网膜疾病或作为先导化合物的潜力。
