Doxycycline Attenuates Endotoxin-Induced Uveitis by Prostaglandin E2-EP4 Signaling
Doxycycline Attenuates Endotoxin-Induced Uveitis by Prostaglandin E2-EP4 Signaling
复制标题
多西环素通过前列腺素 E2-EP4 信号减弱内毒素诱发的葡萄膜炎
DOI：
10.1167/iovs.15-17045
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发表时间：
2015-10-01
影响因子：
4.4
通讯作者：
Liang, Dan
中科院分区：
文献类型：
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作者：
Huang, Jingwen;Su, Wenru;Liang, Dan
目的.目的：探讨强力霉素对实验性葡萄膜炎的抗炎作用及其机制。患有内毒素诱导的葡萄膜炎（EIU）的大鼠通过腹膜内注射接受多西环素（1.5mg/kg）或对照媒介物。在裂隙灯下对临床评分进行分级。体外培养大鼠腹腔巨噬细胞进一步探讨强力霉素的抗炎作用机制。分析一氧化氮（NO）、肿瘤坏死因子-α、IL-1 β、前列腺素E2（PGE 2）、环氧合酶（考克斯）-2、I kappa B-alpha（I kappa B-alpha）、诱导型一氧化氮合酶（iNOS）、Akt、caspase-3和核因子-κ B（NF-κ B）的水平。多西环素治疗显著降低了EIU的临床评分（P < 0.001），炎性细胞浸润、蛋白浓度以及房水（AqH）中NO、TNF-α和IL-1 β的产生显著降低。在体外，多西环素通过调节PI 3 K/Akt/I κ B-α/NF-κ B通路显著抑制腹腔巨噬细胞中NO、IL-1 β和TNF-α的产生。重要的是，我们发现强力霉素在体内和体外均显著增强COX 2表达和PGE 2产生。更重要的是，阻断PGE 2的EP 4受体显著逆转了多西环素介导的巨噬细胞抑制和体外PI 3 K/Akt通路。此外，同时注射EP 4拮抗剂和多西环素可显著阻断多西环素介导的EIU衰减。多西环素可以改善EIU，PGE 2-EP 4信号通路是多西环素体内外抗炎作用的关键。
PURPOSE. We explored the anti-inflammatory effects of doxycycline in experimental uveitis and the underlying mechanisms.METHODS. Rats with endotoxin-induced uveitis (EIU) received doxycycline (1.5 mg/kg) or the control vehicle via intraperitoneal injection. Clinical scores were graded under a slit lamp. Rat peritoneal macrophages were used in vitro to further explore the anti-inflammatory mechanisms of doxycycline. The levels of nitric oxide (NO), TNF-alpha, IL-1 beta, prostaglandin E2 (PGE2), cyclooxygenase (COX)-2, I kappa B-alpha (I kappa B-alpha), inducible nitric oxide synthase (iNOS), Akt, caspase-3, and nuclear factor-kappa B (NF-kappa B) were analyzed.RESULTS. Treatment with doxycycline dramatically reduced the clinical scores of EIU (P < 0.001), with significant decreases in inflammatory cell infiltration, protein concentrations, and the production of NO, TNF-alpha, and IL-1 beta in the aqueous humor (AqH). In vitro, doxycycline significantly inhibited the production of NO, IL-1 beta, and TNF-alpha in peritoneal macrophages by modulating the PI3K/Akt/I kappa B-alpha/NF-kappa B pathway. Importantly, we found that doxycycline significantly enhanced COX2 expression and PGE2 production both in vivo and in vitro. More importantly, blockade of the EP4 receptor of PGE2 significantly reversed the doxycycline-mediated inhibition of macrophages and the PI3K/Akt pathway in vitro. Furthermore, simultaneous injection of an EP4 antagonist and doxycycline significantly blocked the doxycycline-mediated attenuation of EIU.CONCLUSIONS. Doxycycline can ameliorate EIU, and PGE2-EP4 signaling is essential for the anti-inflammatory effects of doxycycline in vitro and in vivo.