Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Medicine, Biology and Health, University of Manchester, Manchester, UK.
Department of Pharmacy, Faculty of Pharmacy, University of Concepción, Barrio Universitario, Concepción, Chile.
J Pharm Pharmacol. 2018 Jun;70(6):713-722. doi: 10.1111/jphp.12893. Epub 2018 Mar 1.
The effects of anti-inflammatory glucocorticoids dexamethasone (DX) and hydrocortisone (HC), pro-inflammatory cytokine interleukin-1β (IL-1β) and dietary long-chain polyunsaturated fatty acids (PUFAs) on expression and activity of the ATP-binding cassette transporter P-glycoprotein (P-GP) were studied in porcine brain endothelial cells (PBECs).
Primary PBECs were treated for 24 h with glucocorticoids, IL-1β and long-chain PUFAs. P-GP activity was determined by measuring intracellular calcein accumulation and P-GP expression by Western blotting. The effect of PUFAs on membrane fluidity was assessed by fluorescence recovery after photobleaching (FRAP).
Dexamethasone, HC and IL-1β significantly increased P-GP expression and activity. The effect of IL-1β was attenuated by the IL-1 receptor antagonist (IL-1RA). This is the first report of the combined actions of IL-1β and IL-1RA on P-GP expression and the first evidence of glucocorticoid-mediated P-GP up-regulation in PBECs. Arachidonic acid (AA), docosahexaenoic acid (DHA) and eicosapentenoic acid (EPA) significantly decreased P-GP activity without affecting expression or membrane fluidity. AA, DHA and EPA counteracted IL-1β-mediated increases in P-GP activity, while AA and EPA, but not DHA, counteracted glucocorticoid-mediated increase in P-GP activity.
While glucocorticoids and IL-1β possess opposing actions in inflammation, they demonstrate functional consistency by increasing P-GP expression and activity in PBECs.
研究抗炎性糖皮质激素地塞米松（DX）和氢化可的松（HC）、促炎性细胞因子白细胞介素-1β（IL-1β）和膳食长链多不饱和脂肪酸（PUFAs）对猪脑内皮细胞（PBECs）中 ATP 结合盒转运蛋白 P-糖蛋白（P-GP）的表达和活性的影响。
用糖皮质激素、IL-1β 和长链 PUFAs 处理原代 PBECs 24 小时。通过测量细胞内钙黄绿素积累来测定 P-GP 活性，并通过 Western blot 测定 P-GP 表达。通过荧光恢复后光漂白（FRAP）评估 PUFAs 对膜流动性的影响。
地塞米松、HC 和 IL-1β 显著增加了 P-GP 的表达和活性。IL-1β 的作用被 IL-1 受体拮抗剂（IL-1RA）减弱。这是首次报道 IL-1β 和 IL-1RA 对 P-GP 表达的联合作用，也是首次证明糖皮质激素介导 PBECs 中 P-GP 上调的证据。花生四烯酸（AA）、二十二碳六烯酸（DHA）和二十碳五烯酸（EPA）显著降低了 P-GP 活性，而不影响表达或膜流动性。AA、DHA 和 EPA 拮抗了 IL-1β 介导的 P-GP 活性增加，而 AA 和 EPA，但不是 DHA，拮抗了糖皮质激素介导的 P-GP 活性增加。
虽然糖皮质激素和 IL-1β 在炎症中具有相反的作用，但它们通过增加 PBECs 中 P-GP 的表达和活性表现出功能一致性。
