Antigenotoxic and antioxidant activities of isorhamnetin 3-O neohesperidoside from Acacia salicina

Abstract

Antioxidant activity of isorhamnetin 3-O neohesperidoside (I3ON), isolated from the leaves of Acacia salicina, was determined by the ability of this compound to inhibit lipid peroxidation and to protect against hydroxyl radical–induced DNA damage in pKS plasmid DNA and Escherichia coli cultures. Antigenotoxic activity was assessed by using the comet assay. The IC₅₀ value of the inhibitory activity toward lipid peroxidation by I3ON is 0.6 mM. This compound was also able to protect against hydroxyl radical–induced DNA damage in pKS plasmid DNA. Moreover, this compound induced an inhibitory activity toward H₂O₂-induced genotoxicity. The protective effect exhibited by this molecule was also determined by analysis of gene expression as a response to an oxidative stress, using a cDNA microarray. Transcription of several genes related to the antioxidant system (HMOX2 and TXNL) and to the DNA repair pathway (XPC, POLD1, POLD2, PCNA, DDIT3, APEX, and LIG4) were upregulated after incubation with I3ON. Taken together, these observations provide evidence that the I3ON, isolated from the leaves of A. salicina, is able to protect cells against oxidative stress.

Keywords::

• Isorhamnetin 3-O neohesperidoside
• A. salicina
• comet assay
• antioxidant capacity
• cDNA micro-array

Acknowledgements

This research was supported by the "Ministére Tunisien de l'Enseignement Supérieur et de la Recherche Scientifique", "la Région Rhone-Alpes" and the "Ministére français des Affaires Etrangeres (Action Intégrée de Coopération Inter universitaire Franco-Tunisienne, CMCU 07 G0836 PAR).