Bertling F, Bendix I, Drommelschmidt K, Wisniewski H G, Felderhoff-Mueser U, Keller M, Prager S
Dept. of Pediatrics I-Neonatology, University Hospital Essen, University Duisburg-Essen, Germany.
Dept. of Microbiology, New York University School of Medicine, New York, USA.
Exp Neurol. 2016 May;279:283-289. doi: 10.1016/j.expneurol.2016.03.005. Epub 2016 Mar 5.
Inflammation is an important factor contributing to developmental brain injury in preterm infants. Although tumor necrosis factor-inducible gene 6 protein (TSG-6) has immunomodulatory effects in several inflammatory conditions of adult animals, nothing is currently known about the role of TSG-6 in the developing brain, its impact on perinatal inflammation and its therapeutic potential. The aim of the current work was 1) to characterize the developmental expression of TSG-6 in the newborn rat brain, 2) to evaluate the impact of LPS exposure on TSG-6 expression and 3) to assess the therapeutic potential of exogenous TSG-6 administration. Brain hemispheres of healthy Wistar rats (postnatal day 1-postnatal day 15 (P1-P15)) were evaluated with regard to the physiological expression of TSG-6. LPS-treated rats (0.25mg/kg LPS i.p. on P3) were analyzed for inflammation-induced changes in TSG-6 and cytokine expression. To evaluate whether exogenous recombinant human (rh)TSG-6 affects inflammation-induced brain injury, newborn Wistar rats, exposed to LPS on P3, were treated with rhTSG-6 i.p. (four repetitive doses of 2.25mg/kg every 12h, first dose 3h before LPS injection). PCR, Western blotting and multiplex ELISA were performed according to standard protocols. TSG-6 is physiologically expressed in the developing brain with a linear increase in expression from P1 to P15 at the mRNA level. At P6, regional differences in TSG-6 expression in the cortex, thalamus and striatum were detected at mRNA and protein level. Furthermore, TSG-6 gene expression was significantly increased by inflammation (induced by LPS treatment). Combined treatment with LPS and TSG-6 vs. LPS exposure alone, resulted in significant down-regulation of cleaved caspase-3, a marker of apoptosis and neuronal plasticity. In addition, several inflammatory serum markers were decreased after TSG-6 treatment. Finally, TSG-6 is physiologically expressed in the developing brain. Changes of TSG-6 expression associated with inflammation suggest a role of TSG-6 in neuroinflammation. Reduction of cleaved caspase-3 by TSG-6 treatment demonstrates the putative neuroprotective potential of exogenous TSG-6 administration in inflammation-induced developmental brain injury.
炎症是导致早产儿脑发育损伤的一个重要因素。尽管肿瘤坏死因子诱导基因6蛋白（TSG-6）在成年动物的几种炎症状态中具有免疫调节作用，但目前对于TSG-6在发育中的大脑中的作用、其对围产期炎症的影响及其治疗潜力尚不清楚。当前研究的目的是：1）描述TSG-6在新生大鼠大脑中的发育表达特征；2）评估脂多糖（LPS）暴露对TSG-6表达的影响；3）评估外源性给予TSG-6的治疗潜力。对健康Wistar大鼠（出生后第1天至出生后第15天（P1-P15））的脑半球进行了TSG-6生理表达方面的评估。对LPS处理的大鼠（在P3腹腔注射0.25mg/kg LPS）分析炎症诱导的TSG-6和细胞因子表达变化。为了评估外源性重组人（rh）TSG-6是否影响炎症诱导的脑损伤，对在P3暴露于LPS的新生Wistar大鼠腹腔注射rhTSG-6（每12小时重复4次剂量为2.25mg/kg，第一剂在LPS注射前3小时）。按照标准方案进行聚合酶链反应（PCR）、蛋白质免疫印迹法和多重酶联免疫吸附测定（ELISA）。TSG-6在发育中的大脑中生理性表达，在mRNA水平上从P1到P15表达呈线性增加。在P6时，在皮质、丘脑和纹状体中检测到TSG-6在mRNA和蛋白质水平上的区域差异。此外，炎症（由LPS处理诱导）显著增加了TSG-6基因表达。LPS与TSG-6联合处理与单独LPS暴露相比，导致凋亡和神经元可塑性标志物裂解的半胱天冬酶-3显著下调。此外，TSG-6处理后几种炎症血清标志物减少。最后，TSG-6在发育中的大脑中生理性表达。与炎症相关的TSG-6表达变化表明TSG-6在神经炎症中起作用。TSG-6处理使裂解的半胱天冬酶-3减少，证明了外源性给予TSG-6在炎症诱导的发育性脑损伤中具有假定的神经保护潜力。
