title: Molecular Dynamics Simulation Study of Permeation of Molecules through Skin Lipid Bilayer.
abstract: Stratum Corneum (SC), the outermost layer of skin, is mainly responsible for skin's barrier function. The complex lipid matrix of SC determines these barrier properties. In this study, the lipid matrix is modeled as an equimolar mixture of ceramide (CER), cholesterol (CHOL), and free fatty acid (FFA). The permeation of water, oxygen, ethanol, acetic acid, urea, butanol, benzene, dimethyl sulfoxide (DMSO), toluene, phenol, styrene, and ethylbenzene across this layer is studied using a constrained MD simulations technique. Several long constrained simulations are performed at a skin temperature of 310 K under NPT conditions. The free energy profiles and diffusion coefficients along the bilayer normal have been calculated for each molecule. Permeability coefficients are also calculated and compared with experimental data. The main resistance for the permeation of hydrophilic and hydrophobic permeants has been found to be in the interior of the lipid bilayer and near the lipid-water interface, respectively. The obtained permeability is found to be a few orders of magnitude higher than experimental values for hydrophilic molecules while for hydrophobic molecules more discrepancy was observed. Overall, the qualitative ranking is consistent with the experiments.
authors: Physical Science Research Area, TCS Research, Tata Research Development and Design Centre, Tata Consultancy Services , 54B, Hadapsar Industrial Estate, Pune - 411013, India.
authors: Rakesh
authors: R
authors: Gupta
authors: Physical Science Research Area, TCS Research, Tata Research Development and Design Centre, Tata Consultancy Services , 54B, Hadapsar Industrial Estate, Pune - 411013, India.
authors: D B
authors: DB
authors: Sridhar
authors: Physical Science Research Area, TCS Research, Tata Research Development and Design Centre, Tata Consultancy Services , 54B, Hadapsar Industrial Estate, Pune - 411013, India.
authors: Beena
authors: B
authors: Rai
mesh_terms: D019342:Acetic Acid / Q000737:chemistry; D001554:Benzene / Q000737:chemistry; D001555:Benzene Derivatives / Q000737:chemistry; D000440:Butanols / Q000737:chemistry; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D000431:Ethanol / Q000737:chemistry; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008051:Lipid Bilayers / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D010100:Oxygen / Q000737:chemistry; D010539:Permeability; D019800:Phenol / Q000737:chemistry; D012867:Skin / Q000737:chemistry*; D020058:Styrene / Q000737:chemistry; D014050:Toluene / Q000737:chemistry; D014508:Urea / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D001555:Benzene Derivatives; D000440:Butanols; D008051:Lipid Bilayers; D014867:Water; D019800:Phenol; D014050:Toluene; D000431:Ethanol; D020058:Styrene; D014508:Urea; D001554:Benzene; C004912:ethylbenzene; D019342:Acetic Acid; D010100:Oxygen; D004121:Dimethyl Sulfoxide