Doctorado en Farmacología., CUCS-Universidad de Guadalajara, Guadalajara, Jalisco, Mexico.
Departamento de Ciencias de la Salud, CUALTOS-Universidad de Guadalajara, Tepatitlan, Jalisco, Mexico.
Neurotox Res. 2020 Aug;38(2):447-460. doi: 10.1007/s12640-020-00207-y. Epub 2020 May 14.
Several pathophysiological processes involve Hypoxia conditions, where the nervous system is affected as well. We postulate that the GABAergic system is especially sensitive. Furthermore, drugs improving the resistance to hypoxia have been investigated, such as the neurosteroid dehydroepiandrosterone sulfate (DHEAS) which has shown beneficial effects in hypoxic processes in mammals; however, at the cellular level, its exact mechanism of action has yet to be fully elucidated. Here, we used a chemical hypoxia model through sodium sulfite (SS) exposure in Caenorhabditis elegans (C. elegans), a nematode whose response to hypoxia involves pathways and cellular processes conserved in mammals, and that allows study the direct effect of DHEAS without its conversion to sex hormones. This work aimed to determine the effect of DHEAS on damage to the GABAergic system associated with SS exposure in C. elegans. Worms were subjected to nose touch response (Not Assay) and observed in epifluorescence microscopy. DHEAS decreased the shrinkage response of Not Assay and the level of damage in GABAergic neurons on SS-exposed worms. Also, the enhanced nuclear localization of DAF-16 and consequently the overexpression of chaperone HSP-16.2 by hypoxia were significantly reduced in SS + DHEAS exposed worms. As well, DHEAS increased the survival rate of worms exposed to hydrogen peroxide. These results suggest that hypoxia-caused damage over the GABAergic system was prevented at least partially by DHEAS, probably through non-genomic mechanisms that involve its antioxidant properties related to its chemical structure.
几种病理生理过程涉及缺氧条件,神经系统也会受到影响。我们假设 GABA 能系统特别敏感。此外,已经研究了一些能提高缺氧抗性的药物,如神经甾体脱氢表雄酮硫酸盐(DHEAS),它在哺乳动物的缺氧过程中显示出有益的效果;然而,在细胞水平上,其确切的作用机制尚未完全阐明。在这里,我们使用化学缺氧模型,通过亚硫酸钠(SS)暴露在秀丽隐杆线虫(C. elegans)中,线虫对缺氧的反应涉及到哺乳动物中保守的途径和细胞过程,并且可以在不将其转化为性激素的情况下研究 DHEAS 的直接作用。这项工作旨在确定 DHEAS 对 SS 暴露引起的 GABA 能系统损伤的影响。用线虫的触鼻反应(Not Assay)和荧光显微镜观察线虫。DHEAS 降低了 Not Assay 的收缩反应和 SS 暴露线虫 GABA 能神经元的损伤水平。此外,缺氧诱导的 DAF-16 的核定位增强,以及伴侣 HSP-16.2 的过表达,在 SS+DHEAS 暴露的线虫中显著减少。此外,DHEAS 提高了暴露于过氧化氢的线虫的存活率。这些结果表明,DHEAS 至少部分地防止了 GABA 能系统因缺氧引起的损伤,这可能是通过非基因组机制实现的,这些机制涉及到与其化学结构相关的抗氧化特性。