Department of Poisoning and Occupational Diseases, Emergency Medicine, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China; Department of Occupational and Environmental Health, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China.
Department of Occupational and Environmental Health, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, 250012, China.
Biomed Pharmacother. 2023 Oct;166:115310. doi: 10.1016/j.biopha.2023.115310. Epub 2023 Aug 11.
To preliminarily explore, whether glucocorticoids have a therapeutic effect on diquat-induced acute kidney injury in rats.
150 Wistar rats were randomly divided into six groups: exposure model group (DQ group), dexamethasone control group (GC group), blank control group (Ctrl group), dexamethasone 2.1 mg/kg dose group (DQ+L-GC group), dexamethasone 4.2 mg/kg dose group (DQ+M-GC group), and dexamethasone 8.4 mg/kg dose group (DQ+H-GC group), with 25 rats in each group. Each group was further divided into five subgroups, 24 h, 3 d, 7 d, 14 d, and 21 d after exposure, according to the feeding time and the course of treatment, with five animals in each subgroup. The rats in DQ, DQ+L-GC, DQ+M-GC, and DQ+H-GC groups were administered 115.5 mg/kg diquat by gavage, respectively. Moreover, 30 min after gavage, rats in DQ+L-GC group, DQ+M-GC group, DQ+H-GC group and GC group were intragastric administered dexamethasone 2.1 mg/kg, 4.2 mg/kg, 8.4 mg/kg and 8.4 mg/kg, respectively. After 7 days, the intraperitoneal injection of dexamethasone was changed to 6.3 mg/kg prednisone by intragastric administration. Subsequently, 7 days later, it was changed to 3.15 mg/kg prednisone by intragastric administration until the end of the experiment on 21 days. After the start of the experiment, changes in the conditions of the rats in each group were observed at a fixed time every day, changes in the body weight of the rats were monitored at the same time, and the death of the rats was recorded at 24 h, 3 d, 7 d, 14 d, and 21 d after exposure. The rats were sacrificed by an intraperitoneal injection of 100 mg/kg sodium pentobarbital overdose. Blood was collected by puncture of the inferior vena cava, used to determine Cr and BUN. The upper segment of the left kidney was collected for histopathological examination. Elisa was used to detect neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) in the lower segment of left kidney. TLR4, Myd88, and NF-κB were detected in the right kidney.
(1) After exposure, most rats in DQ group, DQ+L-GC group, DQ+M-GC group and DQ+H-GC group showed shortness of breath, oliguria, diarrhea, yellow hair and other symptoms. No symptoms and related signs were observed in Ctrl group and GC group. (2) The weight of rats in the Ctrl group and the GC group increased slowly during the test. the body weight of the rats in the DQ, DQ+L-GC, DQ+M-GC, and DQ+H-GC groups continued to decrease after self-infection. Body weight dropped to the lowest point at approximately 7 d, and gradually increased from 7 d to 21 d. (3) A small amount of capillary congestion in the medulla was observed after 7 days in the GC group. The DQ group showed tubular atrophy, edema of the epithelial cells, and over time, the tubules were seen dilated and became irregular in shape; large amount of capillary congestion was also observed in the renal cortex and medulla. The renal injury in the DQ+L-GC group was less than that in the DQ group. DQ+H-GC group had no obvious injury before 7 d, but more renal tubules were seen in the DQ+H-GC group from 7 d to 14 d. (4) Compared with the DQ group, there was no difference before 14 d, and at 14 d-21 d, DQ+L-GC group, DQ+M-GC group, DQ+H-GC group all had different degrees of decline. NGAL content: Compared with the DQ group, the content of NGAL and KIM-1 in kidney tissue of the DQ+L-GC, DQ+M-GC, and DQ+H-GC groups decreased compared with the DQ group at each time node. (5) Compared with the Ctrl group, the expression of TNF-α, TLR4, MyD88, NF-κB in the DQ, DQ+L-GC, DQ+M-GC, and DQ+H-GC groups at each time node increased in the renal tissue. The content of TNF-α, TLR4, MyD88, NF-κB in kidney tissue of the DQ+L-GC, DQ+M-GC, and DQ+H-GC groups at each time node was lower than that in the DQ group.
(1) Diquat can cause kidney damage in rats, mainly manifested as renal tubular atrophy, epithelial cell edema, capillary congestion and dilation, and the renal function damage indicators have been improved to varying degrees. (2) Glucocorticoids have therapeutic effects on acute kidney injury in rats exposed to diquat. During the treatment, the efficacy of glucocorticoids did not increase with increasing doses after reaching a dose of 4.2 mg/kg. (3) TLR4 receptor-mediated TLR4/Myd88/NF-κB signaling pathway is involved in the inflammatory response of acute kidney injury in diquat poisoning rats. Glucocorticoids can inhibit the inflammatory response, thereby affecting the expression of TLR4/Myd88/NF-κB signaling pathway-related proteins.
初步探讨地喹氯铵诱导的急性肾损伤大鼠模型中糖皮质激素是否具有治疗作用。
150 只 Wistar 大鼠随机分为 6 组：染毒模型组（DQ 组）、地塞米松对照组（GC 组）、空白对照组（Ctrl 组）、地塞米松 2.1 mg/kg 剂量组（DQ+L-GC 组）、地塞米松 4.2 mg/kg 剂量组（DQ+M-GC 组）和地塞米松 8.4 mg/kg 剂量组（DQ+H-GC 组），每组 25 只。每组再根据染毒时间和治疗疗程分为 24 h、3 d、7 d、14 d 和 21 d 5 个亚组，每个亚组 5 只。DQ、DQ+L-GC、DQ+M-GC 和 DQ+H-GC 组大鼠分别灌胃给予 115.5 mg/kg 百草枯。灌胃后 30 min，DQ+L-GC、DQ+M-GC、DQ+H-GC 组和 GC 组大鼠分别给予地塞米松 2.1、4.2、8.4 和 8.4 mg/kg 灌胃。7 天后，地塞米松腹腔注射改为泼尼松龙 6.3 mg/kg 灌胃，随后第 7 天改为泼尼松龙 3.15 mg/kg 灌胃，直至 21 天实验结束。实验开始后，每天固定时间观察各组大鼠情况变化，同时监测大鼠体重变化，记录染毒后 24 h、3 d、7 d、14 d 和 21 d 大鼠死亡情况。采用 100 mg/kg 戊巴比妥钠腹腔注射过量处死大鼠。经下腔静脉穿刺采集血液，检测 Cr 和 BUN。采集左肾上段进行组织病理学检查。采用 Elisa 法检测左肾下段中性粒细胞明胶酶相关脂质运载蛋白（NGAL）和肾损伤分子-1（KIM-1）。检测右肾 TLR4、Myd88 和 NF-κB。
（1）染毒后，DQ 组、DQ+L-GC 组、DQ+M-GC 组和 DQ+H-GC 组大鼠多出现呼吸急促、少尿、腹泻、毛发黄等症状，Ctrl 组和 GC 组大鼠未见相关症状和体征。（2）Ctrl 组和 GC 组大鼠在试验过程中体重增长缓慢，DQ、DQ+L-GC、DQ+M-GC 和 DQ+H-GC 组大鼠自染毒后体重持续下降，体重最低点出现在约 7 d，7 d 后逐渐增加至 21 d。（3）GC 组大鼠肾组织皮质和髓质有少量毛细血管淤血，DQ 组大鼠肾小管萎缩、上皮细胞水肿，随时间推移肾小管扩张，形态不规则；DQ 组大鼠肾皮质和髓质大量毛细血管淤血，组织损伤严重。与 DQ 组相比，DQ+L-GC 组大鼠肾损伤较轻，7 d 时 DQ+H-GC 组大鼠肾小管未见明显损伤，但 7 d 至 14 d 时 DQ+H-GC 组大鼠肾小管数量增加。（4）与 DQ 组相比，14 d 前各时间点差异无统计学意义，14 d-21 d 时 DQ+L-GC 组、DQ+M-GC 组和 DQ+H-GC 组均有不同程度下降。NGAL 含量：与 DQ 组相比，DQ+L-GC、DQ+M-GC 和 DQ+H-GC 组各时间点肾组织中 NGAL 和 KIM-1 的含量均低于 DQ 组。（5）与 Ctrl 组相比，各时间点 DQ、DQ+L-GC、DQ+M-GC 和 DQ+H-GC 组大鼠肾组织中 TNF-α、TLR4、MyD88、NF-κB 的表达均增加，DQ+L-GC、DQ+M-GC 和 DQ+H-GC 组各时间点肾组织中 TNF-α、TLR4、MyD88、NF-κB 的含量均低于 DQ 组。
（1）百草枯可导致大鼠肾脏损伤，主要表现为肾小管萎缩、上皮细胞水肿、毛细血管淤血和扩张，肾功能损伤指标均有不同程度改善。（2）地塞米松对百草枯中毒大鼠急性肾损伤有治疗作用，在达到 4.2 mg/kg 剂量后，地塞米松的疗效未随剂量增加而增加。（3）TLR4 受体介导的 TLR4/Myd88/NF-κB 信号通路参与了百草枯中毒大鼠急性肾损伤的炎症反应，地塞米松可抑制炎症反应，从而影响 TLR4/Myd88/NF-κB 信号通路相关蛋白的表达。
