Department of Physiology, Faculty of Medicine, Cairo University, Cairo, Egypt.
Department of Biochemistry, Faculty of Medicine, Cairo University, Cairo, Egypt.
J Cell Physiol. 2021 Nov;236(11):7516-7532. doi: 10.1002/jcp.30387. Epub 2021 Apr 14.
Inflammatory pathway and disruption in glutamate homeostasis join at the level of the glia, resulting in various neurological disorders. In vitro studies have provided evidence that membrane proteins connexions (Cxs) are involved in glutamate release, meanwhile, excitatory amino-acid transporters (EAATs) are crucial for glutamate reuptake (clearance). Moreover, pannexin-1 (Panx-1) activation is more detrimental to neurons. Their expression patterns during inflammation and the impacts of IκB kinase (IKK) inhibition, morphine, and galantamine on the inflammatory-associated glutamate imbalance remain elusive. To investigate this, rats were injected with saline or lipopolysaccharide. Thereafter, vehicles, morphine, galantamine, and BAY-117082 were administered in different groups of animals. Subsequently, electroencephalography, enzyme-linked immunosorbent assay, western blot, and histopathological examinations were carried out and various indicators of inflammation and glutamate level were determined. Parallel analysis of Cxs, Panx-1, and EAAts in the brain was performed. Our findings strengthen the concept that unregulated expressions of Cxs, Panx-1, and EAATs contribute to glutamate accumulation and neuronal cell loss. Nuclear factor-kB (NF-κB) pathway can significantly contribute to glutamate homeostasis via modulating Cxs, Panx-1, and EAATs expressions. BAY-117082, via inhibition of IkK, promoted the anti-inflammatory effects of morphine as well as galantamine. We concluded that NF-κB is an important component of reshaping the expressions of Cxs, panx-1, and EAATs and the development of glutamate-induced neuronal degeneration.
炎症途径和谷氨酸稳态失衡在神经胶质细胞水平上相互作用,导致各种神经紊乱。体外研究已经证明,膜蛋白连接子(Connexions,Cxs)参与谷氨酸释放,同时,兴奋性氨基酸转运体(Excitatory Amino-Acid Transporters,EAATs)对于谷氨酸重摄取(清除)至关重要。此外,连接蛋白-1(Pannexin-1,Panx-1)的激活对神经元更为有害。它们在炎症期间的表达模式,以及 IκB 激酶(IκB Kinase,IKK)抑制、吗啡和加兰他敏对炎症相关谷氨酸失衡的影响仍不清楚。为了研究这一点,大鼠被注射盐水或脂多糖。此后,在不同的动物组中给予载体、吗啡、加兰他敏和 BAY-117082。随后进行脑电图、酶联免疫吸附测定、western blot 和组织病理学检查,并确定炎症和谷氨酸水平的各种指标。同时对大脑中的 Cxs、Panx-1 和 EAAts 进行平行分析。我们的研究结果加强了这样一种概念,即 Cxs、Panx-1 和 EAATs 的不受调节表达导致谷氨酸积累和神经元细胞丢失。核因子-κB(Nuclear Factor-kB,NF-κB)途径通过调节 Cxs、Panx-1 和 EAATs 的表达,显著有助于谷氨酸稳态。BAY-117082 通过抑制 IkK,促进了吗啡和加兰他敏的抗炎作用。我们得出结论,NF-κB 是重塑 Cxs、panx-1 和 EAATs 表达以及谷氨酸诱导的神经元变性发展的重要组成部分。