Tang Yaliang, Wolk Barbara, Kendall Debra A
Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269, USA.
J Cell Signal. 2021;2(2):85-93. doi: 10.33696/signaling.2.038.
Neuroinflammation is closely associated with various diseases including neuropathic pain. Microglia are immune cells in the central nervous system which are the main players of immunity and inflammation. Since microglia are activated by nerve injury, and they produce proinflammatory mediators to cause neuropathic pain, targeting activated microglia is considered to be a strategy for treating neuropathic pain. Activation of the cannabinoid CB receptor is known to have anti-inflammatory effects in microglia. ABK5-1 is a CB subtype selective agonist which inhibits IL-1β and IL-6 production in the microglia cell line BV-2. The purpose of the current study is to further analyze anti-inflammatory effects of ABK5 in terms of different cytokines and the possible pathway involved in the effect in the BV-2 cell line.
A cytokine array was performed to screen the effect of ABK5-1 on forty inflammatory mediators in BV-2 cells. Changes of the inflammatory mediators was further supported by mRNA analysis, and a possible signaling molecule that involved the observation was evaluated by western blot.
Stimulating BV-2 cells by lipopolysaccharide increased expression of eleven inflammatory mediators, and ABK5-1 treatment resulted in more than a 50% decrease of sICAM1, IL-6, and RANTES. Real-time PCR results showed a decrease of G-CSF, ICAM1, MCP-1, MIP-1α, and MIP-1β mRNA levels. Western blot analysis showed that ABK5-1 inhibited LPS-induced ERK phosphorylation, which can be a mechanism of ABK5-1-mediated anti-inflammatory effect.
Our current results support the possibility that ABK5-1 is an anti-inflammatory drug for microglia.
神经炎症与包括神经性疼痛在内的多种疾病密切相关。小胶质细胞是中枢神经系统中的免疫细胞，是免疫和炎症的主要参与者。由于小胶质细胞会被神经损伤激活，并产生促炎介质导致神经性疼痛，因此靶向激活的小胶质细胞被认为是治疗神经性疼痛的一种策略。已知大麻素CB受体的激活在小胶质细胞中具有抗炎作用。ABK5-1是一种CB亚型选择性激动剂，可抑制小胶质细胞系BV-2中白细胞介素-1β（IL-1β）和白细胞介素-6（IL-6）的产生。本研究的目的是从不同细胞因子方面进一步分析ABK5的抗炎作用以及在BV-2细胞系中该作用可能涉及的途径。
进行细胞因子阵列分析以筛选ABK5-1对BV-2细胞中40种炎症介质的影响。通过mRNA分析进一步支持炎症介质的变化，并通过蛋白质印迹法评估参与该观察结果的可能信号分子。
用脂多糖刺激BV-2细胞可增加11种炎症介质的表达，而ABK5-1处理可使可溶性细胞间黏附分子-1（sICAM1）、IL-6和调节激活正常T细胞表达和分泌因子（RANTES）减少超过50%。实时聚合酶链反应（PCR）结果显示粒细胞集落刺激因子（G-CSF）、细胞间黏附分子-1（ICAM1）、单核细胞趋化蛋白-1（MCP-1）、巨噬细胞炎性蛋白-1α（MIP-1α）和巨噬细胞炎性蛋白-1β（MIP-1β）的mRNA水平降低。蛋白质印迹分析表明ABK5-1抑制脂多糖诱导的细胞外信号调节激酶（ERK）磷酸化，这可能是ABK5-1介导的抗炎作用机制之一。
我们目前的结果支持ABK5-1可能是一种用于小胶质细胞的抗炎药物这一可能性。
