Institute of Chemistry, Federal University of Uberlândia, MG, Brazil.
Anhanguera University of São Paulo (UNIAN-SP), SP, Brazil.
Arch Biochem Biophys. 2021 Jan 15;697:108665. doi: 10.1016/j.abb.2020.108665. Epub 2020 Nov 5.
The lipid composition impacts directly on the structure and function of the cytoplasmic as well as organelle membranes. Depending on the type of membrane, specific lipids are required to accommodate, intercalate, or pack membrane proteins to the proper functioning of the cells/organelles. Rather than being only a physical barrier that separates the inner from the outer spaces, membranes are responsible for many biochemical events such as cell-to-cell communication, protein-lipid interaction, intracellular signaling, and energy storage. Photochemical reactions occur naturally in many biological membranes and are responsible for diverse processes such as photosynthesis and vision/phototaxis. However, excessive exposure to light in the presence of absorbing molecules produces excited states and other oxidant species that may cause cell aging/death, mutations and innumerable diseases including cancer. At the same time, targeting key compartments of diseased cells with light can be a promising strategy to treat many diseases in a clinical procedure called Photodynamic Therapy. Here we analyze the relationships between membrane alterations induced by photo-oxidation and the biochemical responses in mammalian cells. We specifically address the impact of photosensitization reactions in membranes of different organelles such as mitochondria, lysosome, endoplasmic reticulum, and plasma membrane, and the subsequent responses of eukaryotic cells.
脂质组成直接影响细胞质和细胞器膜的结构和功能。根据膜的类型，需要特定的脂质来容纳、插入或包装膜蛋白，以实现细胞/细胞器的正常功能。膜不仅仅是分隔内部和外部空间的物理屏障，还负责许多生化事件，如细胞间通讯、蛋白-脂质相互作用、细胞内信号转导和能量储存。光化学反应在许多生物膜中自然发生，负责多种过程，如光合作用和视觉/趋光性。然而，在有吸收分子的情况下过度暴露于光线下会产生激发态和其他氧化剂，可能导致细胞衰老/死亡、突变和无数疾病，包括癌症。同时，用光靶向患病细胞的关键隔室可能是一种有前途的策略，可以在称为光动力疗法的临床程序中治疗许多疾病。在这里，我们分析了光氧化引起的膜改变与哺乳动物细胞生化反应之间的关系。我们特别探讨了光致敏反应对不同细胞器（如线粒体、溶酶体、内质网和质膜）膜的影响，以及真核细胞的后续反应。
