Intensive Care Unit, Linyi Central Hospital, Linyi, Shandong, China.
Intensive Care Unit, Ju County People's Hospital, Rizhao, Shandong, China.
Int Wound J. 2020 Feb;17(1):100-106. doi: 10.1111/iwj.13237. Epub 2019 Nov 8.
The objective of this study is to investigate the mechanism whereby innate immune molecule surfactant protein D (SP-D) attenuates sepsis-induced acute kidney injury (AKI) through modulating apoptosis and nuclear factor kappa-B (NFκB)-mediated inflammation. In the present study, a mouse sepsis model was established by cecal ligation and puncture in SP-D knockout (KO) mice and wild-type (WT) mice. A sham-operated group was included as the control. The experimental materials were extracted 6 and 24 hours postoperatively. The plasma levels of tumour necrosis factor alpha (TNF-α) and MCP-1 were determined by enzyme-linked immunosorbent assay (ELISA). Apoptosis was measured by double staining with Annexin V/propidium iodide and flow cytometry. The levels of NFκB in renal tissues were measured by ELISA and Western blotting assay. Apoptosis was detected by TUNEL assays. There were no significant differences in plasma TNF-α levels between the WT sham group and the KO sham group at 6 and 24 hours postoperatively (P < .05), but the levels of TNF-α in the WT sepsis and KO sepsis groups were significantly higher than those in controls (P < .05). The levels of TNF-α in the KO sepsis group were significantly higher than those of the WT sepsis group (P < .05). TNF-α levels in the WT sepsis group and the KO sepsis group at 24 hours postoperatively were significantly higher than those at 6 hours postoperatively (P < .05). The levels of MCP-1 in the WT sepsis group and the KO sepsis group at 6 and 24 hours postoperatively were significantly higher than those in the control group (P < .05), and MCP-1 levels in the KO sepsis group were significantly higher than those in the WT sepsis group (P < .05). MCP-1 levels in the WT sepsis group and the KO sepsis group at 24 hours postoperatively were significantly higher than those at 6 hours postoperatively (P < .05). The expression of SP-D in WT kidneys was significantly lower at 6 and 24 hours postoperatively (P < .05). The number of TUNEL-positive cells in the kidneys from septic SP-D KO mice was significantly higher (P < .05). The levels of NFκB in septic mice were significantly increased at 6 and 24 hours after induction of sepsis compared with the sham-operated group compared with those of septic SP-D KO mice and WT mice (P < .05). Innate immune molecule SP-D significantly decreased plasma levels of inflammatory cytokines in mice and attenuated sepsis-induced AKI by inhibiting NFκB activity and apoptosis.
本研究旨在探讨固有免疫分子肺表面活性物质蛋白 D (SP-D) 通过调节细胞凋亡和核因子 kappa-B (NFκB) 介导的炎症来减轻脓毒症诱导的急性肾损伤 (AKI) 的机制。在本研究中，通过盲肠结扎和穿刺在 SP-D 敲除 (KO) 小鼠和野生型 (WT) 小鼠中建立了小鼠脓毒症模型。包括假手术组作为对照。实验材料分别于术后 6 小时和 24 小时提取。采用酶联免疫吸附试验 (ELISA) 测定肿瘤坏死因子 alpha (TNF-α) 和单核细胞趋化蛋白 1 (MCP-1) 的血浆水平。通过 Annexin V/碘化丙啶双染和流式细胞术测量细胞凋亡。采用 ELISA 和 Western blot 法测定肾组织中 NFκB 的水平。通过 TUNEL 检测法检测细胞凋亡。术后 6 小时和 24 小时，WT 假手术组和 KO 假手术组的 TNF-α 血浆水平无显著差异（P<.05），但 WT 脓毒症组和 KO 脓毒症组的 TNF-α 水平明显高于对照组（P<.05）。KO 脓毒症组的 TNF-α 水平明显高于 WT 脓毒症组（P<.05）。术后 24 小时，WT 脓毒症组和 KO 脓毒症组的 TNF-α 水平明显高于术后 6 小时（P<.05）。术后 6 小时和 24 小时，WT 脓毒症组和 KO 脓毒症组的 MCP-1 血浆水平明显高于对照组（P<.05），KO 脓毒症组的 MCP-1 水平明显高于 WT 脓毒症组（P<.05）。术后 24 小时，WT 脓毒症组和 KO 脓毒症组的 MCP-1 水平明显高于术后 6 小时（P<.05）。WT 肾脏中 SP-D 的表达在术后 6 小时和 24 小时明显降低（P<.05）。脓毒症 SP-D KO 小鼠肾脏中 TUNEL 阳性细胞数明显增加（P<.05）。与假手术组相比，脓毒症诱导后 6 小时和 24 小时，脓毒症小鼠 NFκB 水平明显升高，而 SP-D KO 小鼠和 WT 小鼠的 NFκB 水平明显低于脓毒症小鼠（P<.05）。固有免疫分子 SP-D 可显著降低小鼠血浆中炎症细胞因子水平，并通过抑制 NFκB 活性和细胞凋亡来减轻脓毒症诱导的 AKI。
