Liu Gaohong, Ren Xiaojun, Li Yousong, Li Han
Department of Nephrology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China.
Department of Nephrology, Shanxi Provincial People's Hospital, Taiyuan, China.
Ann Transl Med. 2022 Jun;10(12):693. doi: 10.21037/atm-22-2382.
We sought to investigate the role of midkine (MK) on neutrophil extracellular trap formation (NETosis) and diabetic kidney disease (DKD) progression.
The expression of MK and NETosis in the renal tissue of DKD patients was examined by immunohistochemistry and immunofluorescence, respectively. Neutrophils extracted from mouse bone marrow by gradient centrifugation were treated with MK for this study. A mouse diabetes model was induced by a high-fat diet combined with an intraperitoneal injection of streptozocin (STZ). Antisense oligodeoxynucleotide (ODN) for MK inhibition was administered via tail vein injection.
We found that the expression of MK was increased in the kidney tissue of DKD patients. Additionally, a greater number of neutrophils were primed toward NETosis in the kidney tissue of DKD patients, which was manifested by the increased expression of NETosis biomarkers citrullinated histone H3 (H3Cit) and myeloperoxidase (MPO). , MK treatment concentration-dependently increased neutrophil proliferation (cell counting kit-8). Further, western blot and enzyme-linked immunosorbent assays showed that MK (100 ng/mL) significantly promoted NETosis and the expression of inflammatory factors interleukin (IL)-1 and IL-6 secretion in high-glucose treated neutrophils. In the mouse diabetes model, MK promoted the pathological damage and fibrosis of kidney tissue, as demonstrated by the reversion of the pathological damage and fibrosis by the MK antisense ODN [diabetes mellitus (DM) + MK - ODN] treatment. Additionally, the inhibition of MK reduced the formation of NETs.
MK promotes DKD progression by increasing NETosis.
我们试图研究中期因子（MK）在中性粒细胞胞外诱捕网形成（NETosis）及糖尿病肾病（DKD）进展中的作用。
分别采用免疫组织化学和免疫荧光法检测DKD患者肾组织中MK的表达及NETosis情况。本研究中，通过梯度离心从小鼠骨髓中提取的中性粒细胞用MK进行处理。采用高脂饮食联合腹腔注射链脲佐菌素（STZ）诱导建立小鼠糖尿病模型。通过尾静脉注射给予抑制MK的反义寡脱氧核苷酸（ODN）。
我们发现DKD患者肾组织中MK的表达增加。此外，DKD患者肾组织中有更多的中性粒细胞倾向于发生NETosis，这表现为NETosis生物标志物瓜氨酸化组蛋白H3（H3Cit）和髓过氧化物酶（MPO）的表达增加。MK处理呈浓度依赖性增加中性粒细胞增殖（细胞计数试剂盒-8）。此外，蛋白质印迹法和酶联免疫吸附测定表明，MK（100 ng/mL）显著促进高糖处理的中性粒细胞的NETosis及炎性因子白细胞介素（IL）-1和IL-6的分泌。在小鼠糖尿病模型中，MK促进肾组织的病理损伤和纤维化，而MK反义ODN[糖尿病（DM）+MK-ODN]处理可逆转病理损伤和纤维化，证明了这一点。此外，抑制MK可减少NETs的形成。
MK通过增加NETosis促进DKD进展。
