Zolcsák Ádám, Kiss Bálint, Bozó Tamás, Somkuti Judit, Vona István, Kellermayer Miklós, Herenyi Levente
Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary.
MTA-ELTE "Momentum" Integrable Quantum Dynamics Research Group, Eötvös Loránd University, Budapest, Hungary.
Sci Rep. 2025 Jan 2;15(1):110. doi: 10.1038/s41598-024-83758-w.
Photosensitization has a wide range of applications in vastly distant fields. Three key components must be present at the same time to trigger the related photodynamic effect: light, the photosensitizer (PS) and oxygen. Irradiating the sensitizer leads to the formation of reactive oxygen species (ROS). Since PSs are accumulated preferably in lipid membranes, the study of photoinduced damage to membrane lipids can greatly increase our understanding of the effect of ROS on membranes in pathological as well as therapeutic conditions. We aimed to characterize the topographical and nanomechanical changes in supported lipid bilayers (SLBs) evoked by light-induced ROS formation. SLBs were prepared on mica surfaces by deposition of liposomes containing unsaturated lipid components. Topographical changes of SLBs were imaged by atomic force microscopy (AFM), and ROS-induced nanomechanical alterations of the membranes were assessed by AFM force measurements. To shed light on chemical alterations of the membrane constituents, infrared spectra were recorded. In the AFM images of porphyrin-containing membranes nanoscopic, bilayer-spanning holes were detected after irradiation. The measured rupture forces increased as a result of irradiation. These phenomena did not occur in membranes lacking unsaturated lipid components, emphasizing their role in ROS-mediated disruption confirmed by infrared spectroscopy results.
光敏化在极为广泛的领域有着众多应用。要触发相关的光动力效应，必须同时具备三个关键要素：光、光敏剂（PS）和氧气。照射敏化剂会导致活性氧物种（ROS）的形成。由于光敏剂优先在脂质膜中积累，因此对膜脂质光致损伤的研究能够极大地增进我们对病理及治疗条件下ROS对膜影响的理解。我们旨在表征由光诱导ROS形成所引发的支撑脂质双层（SLB）的形貌和纳米力学变化。通过沉积含有不饱和脂质成分的脂质体在云母表面制备SLB。利用原子力显微镜（AFM）对SLB的形貌变化进行成像，并通过AFM力测量评估ROS诱导的膜纳米力学改变。为了揭示膜成分的化学变化，记录了红外光谱。在含卟啉膜的AFM图像中，照射后检测到纳米级的跨双层孔洞。照射导致测量的破裂力增加。这些现象在缺乏不饱和脂质成分的膜中未出现，红外光谱结果证实了它们在ROS介导的破坏中的作用。
