Department of Nutrition, University of California, Davis, CA 95616, USA.
Department of Pathology and Laboratory Medicine, University of California, Davis Medical Center, Sacramento, CA 95817, USA.
Int J Mol Sci. 2023 Jun 20;24(12):10396. doi: 10.3390/ijms241210396.
Research has found that genes specific to microglia are among the strongest risk factors for Alzheimer's disease (AD) and that microglia are critically involved in the etiology of AD. Thus, microglia are an important therapeutic target for novel approaches to the treatment of AD. High-throughput in vitro models to screen molecules for their effectiveness in reversing the pathogenic, pro-inflammatory microglia phenotype are needed. In this study, we used a multi-stimulant approach to test the usefulness of the human microglia cell 3 (HMC3) cell line, immortalized from a human fetal brain-derived primary microglia culture, in duplicating critical aspects of the dysfunctional microglia phenotype. HMC3 microglia were treated with cholesterol (Chol), amyloid beta oligomers (AβO), lipopolysaccharide (LPS), and fructose individually and in combination. HMC3 microglia demonstrated changes in morphology consistent with activation when treated with the combination of Chol + AβO + fructose + LPS. Multiple treatments increased the cellular content of Chol and cholesteryl esters (CE), but only the combination treatment of Chol + AβO + fructose + LPS increased mitochondrial Chol content. Microglia treated with combinations containing Chol + AβO had lower apolipoprotein E (ApoE) secretion, with the combination of Chol + AβO + fructose + LPS having the strongest effect. Combination treatment with Chol + AβO + fructose + LPS also induced APOE and TNF-α expression, reduced ATP production, increased reactive oxygen species (ROS) concentration, and reduced phagocytosis events. These findings suggest that HMC3 microglia treated with the combination of Chol + AβO + fructose + LPS may be a useful high-throughput screening model amenable to testing on 96-well plates to test potential therapeutics to improve microglial function in the context of AD.
研究发现,小胶质细胞特有的基因是阿尔茨海默病(AD)最强的风险因素之一,小胶质细胞在 AD 的发病机制中起着至关重要的作用。因此,小胶质细胞是治疗 AD 的新方法的重要治疗靶点。需要高通量的体外模型来筛选分子,以测试它们在逆转致病的、促炎的小胶质细胞表型方面的有效性。在这项研究中,我们使用多刺激方法来测试从人胎脑衍生的原代小胶质细胞培养物中永生化的人小胶质细胞 3(HMC3)细胞系在复制功能失调的小胶质细胞表型的关键方面的有用性。单独和组合使用胆固醇(Chol)、淀粉样β寡聚体(AβO)、脂多糖(LPS)和果糖处理 HMC3 小胶质细胞。当用 Chol+AβO+果糖+LPS 组合处理时,HMC3 小胶质细胞的形态发生变化,表现出激活的特征。多种处理增加了 Chol 和胆固醇酯(CE)的细胞含量,但只有 Chol+AβO+果糖+LPS 的组合处理增加了线粒体 Chol 的含量。用含有 Chol+AβO 的组合处理的小胶质细胞 ApoE(ApoE)分泌减少,Chol+AβO+果糖+LPS 的组合处理效果最强。Chol+AβO+果糖+LPS 的组合处理还诱导了 APOE 和 TNF-α 的表达,降低了 ATP 的产生,增加了活性氧(ROS)的浓度,并减少了吞噬作用事件。这些发现表明,用 Chol+AβO+果糖+LPS 组合处理的 HMC3 小胶质细胞可能是一种有用的高通量筛选模型,适用于在 96 孔板上进行测试,以测试潜在的治疗方法,以改善 AD 中小胶质细胞的功能。