脂质体包封的银纳米粒子(AgNP)提高了纳米粒子的摄取并诱导氧化还原失衡,从而激活 caspase 依赖性细胞凋亡。
Liposomal encapsulation of silver nanoparticles (AgNP) improved nanoparticle uptake and induced redox imbalance to activate caspase-dependent apoptosis.
机构信息
School of Physics, Technological University Dublin, Kevin Street, Dublin 8, Ireland.
Nanolab Research Centre, FOCAS Research Institute, Technological University Dublin, Kevin Street, Dublin 8, Ireland.
出版信息
Apoptosis. 2020 Feb;25(1-2):120-134. doi: 10.1007/s10495-019-01584-2.
Macrophages play a crucial role in several diseases' development and progression, such as in cancer and arthritis through ROS generation and inflammation. This makes macrophages a therapeutic target in these diseases. While silver nanoparticles (AgNP) have been widely used as an antibacterial and investigated as anticancer, its potential against macrophages may be limited due to its inherent oxidative mechanism. Here we encapsulated AgNP in a dipalmitoyl-phosphatidyl choline (DPPC) liposome (forming Lipo-AgNP) to suppress AgNP-induced ROS and enhance its cytotoxicity against THP1-differentiated macrophages (TDM). Our findings showed that while Lipo-AgNP had significantly more of a cytotoxic effect on TDMs (p < 0.01), it also significantly suppressed AgNP induced ROS generation and unexpectedly suppressed reduced glutathione (GSH) levels (p < 0.05) resulting in a redox imbalance in comparison to the unexposed control TDMs. Lipo-AgNP was also found to cause an increase DNA damage through H2AX histone phosphorylation and inhibition of Bcl-2 protein expression. This increased the Bax/Bcl2 ratio causing possible release of cytochrome C and subsequent caspase 3/7-dependent apoptosis. It was found that the difference between the mechanism of AgNP and Lipo-AgNP cytotoxicity may have been through the significantly increased Lipo-AgNP uptake by the TDMs as early as 30 min post-exposure (p < 0.05), changing the nanoparticle pharmacokinetic. In conclusion, the improved uptake of AgNP within the liposome caused ROS-independent caspase activation induced by Lipo-AgNP and this was facilitated by increased DNA damage, the induced redox imbalance and an increased Bax/Bcl-2 ratio.
巨噬细胞在几种疾病的发展和进展中发挥着关键作用,例如癌症和关节炎,通过 ROS 的产生和炎症。这使得巨噬细胞成为这些疾病的治疗靶点。虽然银纳米粒子(AgNP)已被广泛用作抗菌剂,并被研究为抗癌药物,但由于其固有氧化机制,其对巨噬细胞的潜在作用可能有限。在这里,我们将 AgNP 包裹在二棕榈酰磷脂酰胆碱(DPPC)脂质体中(形成 Lipo-AgNP),以抑制 AgNP 诱导的 ROS 生成并增强其对 THP1 分化的巨噬细胞(TDM)的细胞毒性。我们的研究结果表明,虽然 Lipo-AgNP 对 TDM 具有更显著的细胞毒性作用(p < 0.01),但它也显著抑制了 AgNP 诱导的 ROS 生成,并出人意料地抑制了还原型谷胱甘肽(GSH)水平的降低(p < 0.05),导致与未暴露的对照 TDM 相比,氧化还原失衡。Lipo-AgNP 还通过 H2AX 组蛋白磷酸化和抑制 Bcl-2 蛋白表达导致 DNA 损伤增加。这增加了 Bax/Bcl2 比值,可能导致细胞色素 C 的释放和随后 caspase 3/7 依赖性细胞凋亡。研究发现,AgNP 和 Lipo-AgNP 细胞毒性的机制差异可能是由于 TDMs 对 Lipo-AgNP 的摄取明显增加,早在暴露后 30 分钟(p < 0.05),改变了纳米颗粒的药代动力学。总之,脂质体内 AgNP 的摄取增加导致 Lipo-AgNP 诱导的 ROS 独立的半胱天冬酶激活,这是通过增加 DNA 损伤、诱导的氧化还原失衡和增加的 Bax/Bcl-2 比值来促进的。