Shahabadi Nahid, Ghaffari Lida
Department of Inorganic Chemistry, Faculty of Chemistry, Razi University, Kermanshah, Iran.
Heliyon. 2024 Sep 25;10(19):e38432. doi: 10.1016/j.heliyon.2024.e38432. eCollection 2024 Oct 15.
In this research, the toxicity of nano-[Cu-(DIP)-EA], a metal nano-complex consisting of ellagic acid and bathophenanthroline ligands, on human serum albumin (HSA) at a protein level was investigated. Molecular docking simulations and spectral analyses were conducted in a simulated physiological environment at pH 7.4 to explore the interaction of nano-[Cu-(DIP)-EA] with HSA. The results represented an increase in albumin absorption upon exposure to nano-[Cu-(DIP)-EA], demonstrating significant interaction between the two compounds. Steady-state and time-resolved fluorescence measurements pointed out that nano-[Cu-(DIP)-EA] induced static quenching of the albumin's intrinsic fluorescence with a high binding affinity of approximately 10 mol/L in a 1:1 interaction ratio. The thermodynamic variables clarified that binding of nano-[Cu-(DIP)-EA] to albumin occurs spontaneously and primarily driven by van der Waals interactions and H-bonds. The results of the computer simulations and the binding displacement experiments utilizing the site markers warfarin and ibuprofen revealed that nano-[Cu-(DIP)-EA] binds to site I within the subdomain IIA of albumin. Circular dichroism analysis elaborated that nano-[Cu-(DIP)-EA] slightly perturbed the microenvironment around of tryptophan residues and diminished the α-helix structure stability to a negligible amount.
在本研究中,研究了由鞣花酸和红菲绕啉配体组成的金属纳米复合物纳米-[Cu-(DIP)-EA]在蛋白质水平上对人血清白蛋白(HSA)的毒性。在pH 7.4的模拟生理环境中进行了分子对接模拟和光谱分析,以探索纳米-[Cu-(DIP)-EA]与HSA的相互作用。结果表明,暴露于纳米-[Cu-(DIP)-EA]后白蛋白吸收增加,表明这两种化合物之间存在显著相互作用。稳态和时间分辨荧光测量指出,纳米-[Cu-(DIP)-EA]以1:1的相互作用比例诱导白蛋白固有荧光的静态猝灭,结合亲和力约为10 mol/L。热力学变量表明,纳米-[Cu-(DIP)-EA]与白蛋白的结合是自发发生的,主要由范德华相互作用和氢键驱动。利用位点标记物华法林和布洛芬进行的计算机模拟和结合置换实验结果表明,纳米-[Cu-(DIP)-EA]与白蛋白亚结构域IIA内的位点I结合。圆二色性分析表明,纳米-[Cu-(DIP)-EA]略微扰乱了色氨酸残基周围的微环境,并将α-螺旋结构稳定性降低到可忽略不计的程度。