Abstract:
Gangliogliomas (GGs) represent the most frequent glioneuronal tumor entity associated with chronic recurrent seizures; rare anaplastic GGs variants retain the glioneuronal character. So far, key mechanisms triggering chronic hyperexcitability in the peritumoral area are unresolved. Based on a recent mouse model for anaplastic GG (BRAFV600E, mTOR activation and Trp53KO) we here assessed the influence of GG-secreted factors on non-neoplastic cells in-vitro. We generated conditioned medium (CM) from primary GG cell cultures to developing primary cortical neurons cultured on multielectrode-arrays and assessed their electrical activity in comparison to neurons incubated with naïve and neuronal CMs. Our results showed that the GG CM, while not affecting the mean firing rates of networks, strongly accelerated the formation of functional networks as indicated increased synchrony of firing and burst activity. Washing out the GG CM did not reverse these effects indicating an irreversible effect on the neuronal network. Mass spectrometry analysis of GG CM detected several enriched proteins associated with neurogenesis as well as gliogenesis, including Gap43, App, Apoe, S100a8, Tnc and Sod1. Concomitantly, immunocytochemical analysis of the neuronal cultures exposed to GG CM revealed abundant astrocytes suggesting that the GG-secreted factors induce astroglial proliferation. Pharmacological inhibition of astrocyte proliferation only partially reversed the accelerated network maturation in neuronal cultures exposed to GG CM indicating that the GG CM exerts a direct effect on the neuronal component. Taken together, we demonstrate that GG-derived paracrine signaling alone is sufficient to induce accelerated neuronal network development accompanied by astrocytic proliferation. Perspectively, a deeper understanding of factors involved may serve as the basis for future therapeutic approaches.
摘要:
神经节胶质瘤(GGs)是与慢性复发性癫痫发作相关的最常见的神经胶质细胞肿瘤实体;罕见的间变性Gs变体保留了神经胶质细胞的特征。到目前为止,引发肿瘤周围区域慢性过度兴奋的关键机制尚未解决。基于最近的间变性GG小鼠模型(BRAFV600E,mTOR激活和Trp53KO),我们在此评估了GG分泌因子在体外对非肿瘤细胞的影响。Wegeneratedconditionalmedium(CM)fromprimaryGGcellculturestodevelopingprimarycelectricalneuronscarriedonmultielectrode-arraysandassessedtheirelectricalactivityincomparedtoneuronsinculatedwithnaiveandneuronicCMs.Our.虽然不影响网络的平均射击率,强烈加速了功能网络的形成,这表明射击和爆发活动的同步性增加。冲洗GGCM并不能逆转这些影响,表明对神经元网络的不可逆影响。GGCM的质谱分析检测到与神经发生以及神经胶质发生相关的几种富集蛋白,包括Gap43,应用程序,Apoe,S100a8、Tnc和Sod1。同时,暴露于GGCM的神经元培养物的免疫细胞化学分析显示,大量的星形胶质细胞表明GG分泌因子诱导星形胶质细胞增殖。星形胶质细胞增殖的药理学抑制仅部分逆转了暴露于GGCM的神经元培养物中加速的网络成熟,表明GGCM对神经元成分具有直接作用。一起来看,我们证明,GG衍生的旁分泌信号单独足以诱导加速的神经元网络发育并伴有星形胶质细胞增殖。透视,对相关因素的更深入了解可能是未来治疗方法的基础.