Nakabe Nami, Kokura Satoshi, Shimozawa Makoto, Katada Kazuhiro, Sakamoto Naoyuki, Ishikawa Takeshi, Handa Osamu, Takagi Tomohisa, Naito Yuji, Yoshida Norimasa, Yoshikawa Toshikazu
Inflammation and Immunology, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Int J Hyperthermia. 2007 May;23(3):217-24. doi: 10.1080/02656730601143295.
The activation of NF-kappaB induces production of inflammatory cytokines and up regulation of endothelial cell adhesion molecules (ECAM). ECAM (e.g., E-selectin, VCAM-1 and ICAM-1) associates to the recruitment of leukocytes into tissue exposed to inflammatory situation. In this study, we investigated the effects of hyperthermia on the activation of NF-kappaB and the up regulation of E-selectin and VCAM-1 in human endothelial cells stimulated by TNF-alpha.
Human arterial endothelial cells (HAEC) were pretreated with hyperthermia for 60 min at 42 degrees C, followed by incubation at 37 degrees C in a passively cooled incubator, before TNF-alpha stimulation. To assess the effects of hyperthermia on TNF-alpha-induced up regulation of ECAM and TNF-alpha-induced activation of NF-kappaB, we measured ECAM by ELISA, and evaluated the activation of NF-kappaB by Western blotting after TNF-alpha stimulation. The accumulation of HO-1, Hsp70 and IkappaBalpha in hyperthermia-treated HAEC was also assessed by Western blotting. To investigate the role of Hsp70, we treated HAEC with geranylgeranylacetone (GGA, Hsp70 inducer) 2 h before hyperthermia, and then measured ECAM in TNF-alpha-stimulated HAEC by ELISA.
Pretreatment of hyperthermia reduced TNF-alpha-induced up regulation of E-selectin and VCAM-1. In addition, accumulation of Hsp70, HO-1 and IkappaBalpha protein were up-regulated after hyperthermia. Furthermore, Western blotting analysis revealed that pretreatment of hyperthermia attenuated TNF-alpha-induced translocation of p65 into the nuclei of HAEC. Moreover, GGA enhanced Hsp70 accumulation induced by hyperthermia. Hyperthermia pretreatment combined with GGA induced further inhibition of TNF-alpha-induced up regulation of ECAM when compared with hyperthermia alone.
Pretreatment of hyperthermia blocks TNF-alpha-induced NF-kappaB activation, resulting in the inhibition of ECAM up regulation in HAEC.
核因子κB（NF-κB）的激活可诱导炎性细胞因子的产生，并上调内皮细胞黏附分子（ECAM）。ECAM（如E-选择素、血管细胞黏附分子-1和细胞间黏附分子-1）与白细胞募集至炎症部位的组织有关。在本研究中，我们调查了热疗对肿瘤坏死因子-α（TNF-α）刺激的人内皮细胞中NF-κB激活及E-选择素和血管细胞黏附分子-1上调的影响。
在TNF-α刺激前，将人动脉内皮细胞（HAEC）在42℃下进行60分钟的热预处理，然后在被动冷却的培养箱中于37℃孵育。为评估热疗对TNF-α诱导的ECAM上调及TNF-α诱导的NF-κB激活的影响，我们通过酶联免疫吸附测定（ELISA）法检测ECAM，并在TNF-α刺激后通过蛋白质印迹法评估NF-κB的激活。还通过蛋白质印迹法评估热预处理的HAEC中血红素加氧酶-1（HO-1）、热休克蛋白70（Hsp70）和核因子κB抑制蛋白α（IκBα）的蓄积情况。为研究Hsp70的作用，我们在热疗前2小时用香叶基香叶基丙酮（GGA，Hsp70诱导剂）处理HAEC，然后通过ELISA法检测TNF-α刺激的HAEC中的ECAM。
热预处理可降低TNF-α诱导的E-选择素和血管细胞黏附分子-1上调。此外，热疗后Hsp70、HO-1和IκBα蛋白的蓄积上调。此外，蛋白质印迹分析显示，热预处理可减弱TNF-α诱导的p65向HAEC细胞核的转位。此外，GGA增强了热疗诱导的Hsp70蓄积。与单独热疗相比，热预处理联合GGA对TNF-α诱导的ECAM上调的抑制作用更强。
热预处理可阻断TNF-α诱导的NF-κB激活，从而抑制HAEC中ECAM的上调。
