title: Modeling Lung Surfactant Interactions with Benzo[a]pyrene.
abstract: By reducing the surface tension of the air-water interface in alveoli, lung surfactant (LS) is crucial for proper functioning of the lungs. It also forms the first barrier against inhaled pathogens. In this study we inspect the interactions of LS models with a dangerous air pollutant, benzo[a]pyrene (BaP). Dipalmitoylphosphatidylcholine (DPPC), 1-palmitoyl-2-oleoylphosphatidylcholine, and their 1:1 mixture are used as LS models. Pressure-area isotherms are employed to study macroscopic properties of the monolayers. We find that addition of BaP has a condensing effect, manifested by lowering the values of surface pressure and shifting the isotherms to smaller areas. Atomistic details of this process are examined by means of molecular dynamics simulations. We show that initially BaP molecules are accumulated in the monolayers. Upon compression, they are forced to the headgroups region and eventually expelled to the subphase. BaP presence results in reduction of monolayer hydration in the hydrophilic region. In the hydrophobic region it induces increased chain ordering, reduction of monolayer fluidity, and advances transition to the liquid condensed phase in the DPPC system.
authors.affiliation: Department of Chemistry, Jagiellonian University, ul. Ingardena 3, 30-060, Kraków, Poland.
authors.forename: Anna
authors.identifier: http://orcid.org/0000-0001-5184-2521
authors.initials: A
authors.lastname: Stachowicz-Kuśnierz
authors.affiliation: Department of Chemistry, Jagiellonian University, ul. Ingardena 3, 30-060, Kraków, Poland.
authors.forename: Sonia
authors.initials: S
authors.lastname: Trojan
authors.affiliation: J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, v.v.i. Dolejškova 3, 18223, Prague 8, Czech Republic.
authors.forename: Lukasz
authors.initials: L
authors.lastname: Cwiklik
authors.affiliation: Department of Chemistry, Jagiellonian University, ul. Ingardena 3, 30-060, Kraków, Poland.
authors.forename: Beata
authors.identifier: http://orcid.org/0000-0003-3950-7514
authors.initials: B
authors.lastname: Korchowiec
authors.affiliation: Department of Chemistry, Jagiellonian University, ul. Ingardena 3, 30-060, Kraków, Poland.
authors.forename: Jacek
authors.identifier: http://orcid.org/0000-0002-9698-7369
authors.initials: J
authors.lastname: Korchowiec
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D001564:Benzo(a)pyrene / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D010713:Phosphatidylcholines / Q000737:chemistry*; D011650:Pulmonary Alveoli / Q000737:chemistry / Q000502:physiology*; D011663:Pulmonary Surfactants; D013500:Surface Tension
chemical_list: D010713:Phosphatidylcholines; D011663:Pulmonary Surfactants; D015060:1,2-Dipalmitoylphosphatidylcholine; C081581:colfosceril palmitate; D001564:Benzo(a)pyrene; C028694:1-palmitoyl-2-oleoylphosphatidylcholine
keywords: air pollution; benzo[a]pyrene; lung surfactant; molecular dynamics; surface pressure-area isotherms