title: Protective effects of curcumin against gamma ray induced conformational change of human serum albumin.
abstract: This study explores the possibility for protection by curcumin during the molecular and structural changes of human serum albumin (HSA) exposed to gamma irradiation. We used a combination of spectroscopic methods to probe the conformational ensemble of the irradiated HSA and finally evaluated the extent of restoration by curcumin. SDS-PAGE study unfolded the formation of cross linked aggregates as a consequence of increasing exposure of gamma radiation. CD and FTIR spectroscopy indicated significant decrease in the alpha helix content of HSA from 57% to 15% with increasing radiation doses. Steady state and time resolved fluorescence studies complemented the spectroscopic measurements, when lifetime decay was significantly reduced from 6.35ns to 0.37ns. Hydrophobic study showed the effectiveness of curcumin for protection at low dose of gamma irradiated HSA samples. We integrated these observations to investigate protein aggregation under increasing gamma radiation and estimated the same in presence of curcumin. It was elucidated, that when HSA is irradiated at low dose of gamma radiation in presence of curcumin, it is capable of retaining the characteristic properties to a higher extent indicating stabilization of molecular structure of HSA by curcumin. A model for curcumin based protection has been proposed utilizing ThT assay.
authors.affiliation: Department of Biochemistry, University of Calcutta, 35, Ballygunge Circular Road, Kolkata 700019, West Bengal, India.
authors.forename: Turban
authors.initials: T
authors.lastname: Kar
authors.affiliation: Jagadis Bose National Science Talent Search, 1300, Rajdanga Main Road, Sector C, East Kolkata Township, Kolkata 700107, West Bengal, India.
authors.forename: Pijush
authors.initials: P
authors.lastname: Basak
authors.affiliation: Department of Biochemistry, University of Calcutta, 35, Ballygunge Circular Road, Kolkata 700019, West Bengal, India.
authors.forename: Rittik Kumar
authors.initials: RK
authors.lastname: Ghosh
authors.affiliation: Department of Biochemistry, University of Calcutta, 35, Ballygunge Circular Road, Kolkata 700019, West Bengal, India; Jagadis Bose National Science Talent Search, 1300, Rajdanga Main Road, Sector C, East Kolkata Township, Kolkata 700107, West Bengal, India. Electronic address: bmaitree@gmail.com.
authors.forename: Maitree
authors.initials: M
authors.lastname: Bhattacharyya
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D003474:Curcumin / Q000494:pharmacology*; D005720:Gamma Rays / Q000009:adverse effects*; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D055503:Protein Multimerization / Q000187:drug effects / Q000528:radiation effects; D017433:Protein Structure, Secondary / Q000187:drug effects / Q000528:radiation effects; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D012709:Serum Albumin / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D011837:Radiation-Protective Agents; D012709:Serum Albumin; D003474:Curcumin
keywords: Bityrosine content; Conformational change; Curcumin; Gamma radiation; Human serum albumin