Phycocyanin (PC), a natural algal protein, is reported for having anti-oxidant and antiinfl ammatory properties. We investigated its ability to attenuate lung infl ammation in mice subjected to X-ray radiation. Male C...Phycocyanin (PC), a natural algal protein, is reported for having anti-oxidant and antiinfl ammatory properties. We investigated its ability to attenuate lung infl ammation in mice subjected to X-ray radiation. Male C57BL/6 mice were assigned to the control, total body irradiation, PC pretreatment, and PC treatment groups. Mice in the PC pretreatment group were gavaged with 200 mg/kg PC for 7 consecutive days before irradiation, and those in the PC treatment group were gavaged with 200 mg/kg PC for 7 consecutive days after irradiation. Lungs were collected on Day 7 after irradiation exposure. Hematoxylin and eosin staining of mouse lung sections showed considerable infl ammation damage 7 days after irradiation compared with the control lung but a reduction in pathological injury in the PC treatment group. Pretreatment or treatment with PC signifi cantly decreased levels of interleukin-6 and tumor necrosis factor-α in the lung, and also increased the relative mRNA expression of superoxide dismutase and glutathione. In vivo, PC signifi cantly reduced the expression of Toll-like receptor TLR2, myeloid diff erentiation primary response Myd88, and nuclear factor NF-κB, at both the transcriptional and translation level. Taken together, these data indicated that PC attenuated lung infl ammatory damage induced by radiation by blocking the TLR2- MyD88-NF-κB signaling pathway. Therefore, PC could be a protective agent against radiation-induced infl ammatory damage in normal tissues.展开更多
选取31头经检测猪圆环病毒2型(PCV2)、猪繁殖与呼吸综合征病毒(PRRSV)抗原和抗体均为阴性的5周龄断奶仔猪,随机分为对照组16头和试验组15头,对照组仔猪每头滴鼻4 mL PBS,试验组仔猪每头滴鼻4 mL 5×105TCID50.mL-1PCV2悬液。于PCV2...选取31头经检测猪圆环病毒2型(PCV2)、猪繁殖与呼吸综合征病毒(PRRSV)抗原和抗体均为阴性的5周龄断奶仔猪,随机分为对照组16头和试验组15头,对照组仔猪每头滴鼻4 mL PBS,试验组仔猪每头滴鼻4 mL 5×105TCID50.mL-1PCV2悬液。于PCV2接种当天剖杀4头仔猪作为对照组,分别于14、21和35 d剖杀4头对照组和5头试验组仔猪,采集肝脏。用激光共聚焦显微镜检测核因子κB/P65(NF-κB/P65)蛋白的核易位变化;蛋白提取法分别提取肝脏细胞核蛋白和胞浆蛋白,Western blot定量检测细胞核中NF-κB/P65和细胞浆中p-IκBα、MyD88蛋白含量的变化;电泳迁移率(EMSA)法检测细胞核中NF-κB DNA的结合率变化。检测结果显示,PCV2接种仔猪,肝脏中NF-κB/P65蛋白核易位逐渐增多,到21 d达到峰值;p-IκBα、MyD88、NF-κB/P65 DNA结合率在接种后均先升高后趋于恢复,并于21 d达到高峰。与对照组仔猪相比,肝脏中MyD88和NF-κB/P65蛋白含量以及NF-κB DNA结合率在14和21 d试验组均显著升高(P<0.05),35 d含量变化不显著;21 d时试验组p-IκBα蛋白含量显著升高。相关性分析显示,NF-κB/P65蛋白含量与MyD88含量、NF-κB DNA结合率之间存在显著正相关,相关系数分别是0.566和0.528。结果表明,PCV2可通过激活MyD88启动NF-κB信号途径;通过IκBα的磷酸化降解激活NF-κB,并促进其进行核易位,使NF-κB与DNA发生结合,调控相关炎性细胞因子的转录和表达。展开更多
基金Supported by the National Key Research and Development Program of China(No.2018YFD0901102)
文摘Phycocyanin (PC), a natural algal protein, is reported for having anti-oxidant and antiinfl ammatory properties. We investigated its ability to attenuate lung infl ammation in mice subjected to X-ray radiation. Male C57BL/6 mice were assigned to the control, total body irradiation, PC pretreatment, and PC treatment groups. Mice in the PC pretreatment group were gavaged with 200 mg/kg PC for 7 consecutive days before irradiation, and those in the PC treatment group were gavaged with 200 mg/kg PC for 7 consecutive days after irradiation. Lungs were collected on Day 7 after irradiation exposure. Hematoxylin and eosin staining of mouse lung sections showed considerable infl ammation damage 7 days after irradiation compared with the control lung but a reduction in pathological injury in the PC treatment group. Pretreatment or treatment with PC signifi cantly decreased levels of interleukin-6 and tumor necrosis factor-α in the lung, and also increased the relative mRNA expression of superoxide dismutase and glutathione. In vivo, PC signifi cantly reduced the expression of Toll-like receptor TLR2, myeloid diff erentiation primary response Myd88, and nuclear factor NF-κB, at both the transcriptional and translation level. Taken together, these data indicated that PC attenuated lung infl ammatory damage induced by radiation by blocking the TLR2- MyD88-NF-κB signaling pathway. Therefore, PC could be a protective agent against radiation-induced infl ammatory damage in normal tissues.
