Molecular interactions of benzophenone UV filters with human serum albumin revealed by spectroscopic techniques and molecular modeling.
Benzophenone (BP)-type UV filters have been widely used in many personal care products to protect human from UV exposure. Their dermal applications can cause direct human health risk following accumulation in bloodstream. Few studies have addressed whether BP-type UV filters could bind and alter the structure and function of human serum albumin (HSA), the major carrier protein in plasma. Four benzophenones, BP-1, BP-2, BP-3 and BP-8 were selected to investigate their potentially toxic interactions with HSA and the intrinsic binding mechanism using combined spectroscopies and molecular docking techniques. Four benzophenones significantly quench the intrinsic fluorescence of HSA via static mode. The competitive binding fluorescence assay and molecular docking both revealed that the benzophenones bind at site II of HSA. Their binding constants range from 1.91 × 10(4)M(-1) to 12.96 × 10(4)M(-1) at 296 K. BP-8 interacts with HSA mainly through hydrogen bonding interactions and van der Waals interactions, while hydrophobic interactions and electrostatic interactions are dominant for interactions between BP-1, BP-2, BP-3 and HSA. Molecular docking revealed that the changes in structural moiety and hydrophobicity of four benzophenones account for their different binding affinities. As further revealed by circular dichroism and time-resolved fluorescence decay, these benzophenones cause global and local structural changes of HSA, which illustrates their potential toxicity to cause structural damage of HSA. Two degradation products of BP-3 have higher binding affinities to HSA, suggesting higher potencies in causing adverse effects on human health.
College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, People's Republic of China.
Feng
F
Zhang
Jing
J
Zhang
Changlun
C
Tong
Yadong
Y
Chen
Shulin
S
Zhuang
Weiping
W
Liu
D001577:Benzophenones / Q000009:adverse effects* / Q000737:chemistry; D001665:Binding Sites; D002942:Circular Dichroism; D017753:Ecosystem; D005453:Fluorescence; D006801:Humans; D006860:Hydrogen Bonding; D008856:Microscopy, Fluorescence; D062105:Molecular Docking Simulation; D017433:Protein Structure, Secondary / Q000187:drug effects*; D012709:Serum Albumin / Q000737:chemistry / Q000187:drug effects*; D013050:Spectrometry, Fluorescence; D055672:Static Electricity; D013473:Sunscreening Agents / Q000009:adverse effects* / Q000737:chemistry; D013696:Temperature; D013816:Thermodynamics; D014466:Ultraviolet Rays
D001577:Benzophenones; D012709:Serum Albumin; D013473:Sunscreening Agents; C047723:benzophenone
Benzophenones; Fluorescence lifetime; Human serum albumin; Molecular docking spectroscopy; UV filters