Anti-inflammatory and Antioxidant Peptide-Conjugates: Modulation of Activity by Charged and Hydrophobic Residues

In the present study, antioxidant and anti-inflammatory activities of a series of quinazolinone-conjugated-peptides were investigated. Substitution of second position of the peptide template GXGVP' by different amino acids of varying hydrophobicity, charge and polarity has been studied. Quinazolinone-peptides with Trp residue emerged out as the highly potential antioxidant whereas the conjugate with Asp moiety turned to be a good anti-inflammatory agent. These data indicate that more hydrophobicity favours antioxidant property and contrarily, presence of charged species in the molecule assists the reduction of inflammation. Further, conjugates having butyl group in the heterocyclic part and free C-terminus in the peptide part exhibited good inflammation reducing property. Thus, variation of hydrophobic groups, charges and polarity of certain amino acids in the peptide segment of the conjugate could be used to develop dual war-head potential therapeutics for treating inflammation and allied diseases.