在过去的几年里,人们对大麻素的神经保护作用越来越感兴趣。本工作的目的是研究在光诱导的视网膜变性(LIRD)的背景下调节大麻素受体1(CB1)的作用,使用类似人类年龄相关性黄斑变性(AMD)和其他外视网膜退行性疾病的许多特征的动物模型。SpragueDawley大鼠(n=28)在右眼玻璃体内注射CB1激动剂(ACEA),或拮抗剂(AM251)。对侧眼睛注射相应的载体作为对照。然后,对大鼠进行连续照射(12,000勒克斯)24小时。通过GFAP免疫组织化学(IHC)处理来自28只动物的视网膜,TUNEL技术,蛋白质印迹(WB),或qRT-PCR。ACEA处理的视网膜显示出外核层(ONL)中凋亡核的数量显着降低,通过WB降低活化的Caspase-3的水平,GFAP-IHC和WB的神经胶质反应性水平较低。qRT-PCR显示ACEA显著降低Bcl-2和CYP1A1的表达。相反,AM251处理的视网膜在ONL中显示出更高数量的凋亡细胞核,WB激活的Caspase-3水平更高,以及通过GFAP-IHC和WB测定的更高水平的神经胶质反应性。AM251增加Bcl-2、Bad、Bax,芳烃受体(AhR),GFAP,和TNFα。总之,CB1受体的刺激,在致病过程开始之前,提高了暴露于LIRD的光感受器的存活率。CB1活性的调节可用作视网膜变性的神经保护策略,值得进一步研究。
In the last few years, an increasing interest in the neuroprotective effect of cannabinoids has taken place. The aim of the present work was to study the effects of modulating cannabinoid receptor 1 (
CB1) in the context of light induced retinal degeneration (LIRD), using an animal model that resembles many characteristics of human age-related macular degeneration (AMD) and other degenerative diseases of the outer retina. Sprague Dawley rats (n = 28) were intravitreally injected in the right eye with either a
CB1 agonist (ACEA), or an antagonist (AM251). Contralateral eyes were injected with respective vehicles as controls. Then, rats were subjected to continuous illumination (12,000 lux) for 24 h. Retinas from 28 animals were processed by GFAP-immunohistochemistry (IHC), TUNEL technique, Western blotting (WB), or qRT-PCR. ACEA-treated retinas showed a significantly lower number of apoptotic nuclei in the outer nuclear layer (ONL), lower levels of activated Caspase-3 by WB, and lower levels of glial reactivity by both GFAP-IHC and WB. qRT-PCR revealed that ACEA significantly decreased the expression of Bcl-2 and CYP1A1. Conversely, AM251-treated retinas showed a higher number of apoptotic nuclei in the ONL, higher levels of activated Caspase-3 by WB, and higher levels of glial reactivity as determined by GFAP-IHC and WB. AM251 increased the expression of Bcl-2, Bad, Bax, Aryl hydrocarbon Receptor (AhR), GFAP, and TNFα. In summary, the stimulation of the
CB1 receptor, previous to the start of the pathogenic process, improved the survival of photoreceptors exposed to LIRD. The modulation of
CB1 activity may be used as a neuroprotective strategy in retinal degeneration and deserves further studies.