Antioxidant and anti-inflammatory properties of marmelosin from Bael (Aegle marmelos L.); Inhibition of TNF-α mediated inflammatory/tumor markers

Oxidative stress and inflammation are important critical factors that are implicated in almost all life style disorders such as diabetes, cardiovascular disease, ulcer and cancer. Current study aimed at isolation and characterization of a furanocoumarin from Bael (Aegle marmelos L.) fruit that can modulate both oxidative stress and inflammation effectively. Ethyl acetate extract of Bael fruit (EAFB) was subjected to HPLC for identification, purified and characterized using FTIR, NMR and ESI-MS analysis. Predominant peak of EAFB at RT 12.54 min on HPLC was identified as marmelosin with molecular weight of m/z similar to 271.2. Marmelosin was evaluated for antioxidant, antiproliferative, apoptotic, cancer (Tyrosinase & Galectin-3) and immunomodulatory (NO, TNF-alpha) potentials employing standard assay systems. Marmelosin possessed potent antioxidant activity with IC50 of similar to 15.4 +/- 0.32 mu M as opposed to standard - gallic acid (IC50 1.1 +/- 0.08 mu M), antiproliferative activity with IC50 of similar to 6.24 +/- 0.16 mu M as opposed to deferoxamine(similar to 10.8 +/- 0.28 mu M) and protected cells against cellular/DNA damage. Anti-inflammatory property was evident with significant reduction in the release of NO (similar to 3.9 fold) and TNF-alpha (similar to 3.4 fold), a pro-inflammatory cytokine, in addition to the inhibition of NF kappa B (similar to 2.7 fold), a transcription factor in Raw 264.7 cells. Marked down regulation of galectin-3 (similar to 5.5 folds) and tyrosinase (similar to 11.1 folds) by gene expression analysis substantiated by tyrosinase inhibition (IC50 - 20.3 +/- 1.26 mu M Vs. Kojic acid IC50 - 24.1 +/- 1.41 mu M) and molecular docking studies strengthened the cancer modulatory property of marmelosin. In addition, marmelosin induced apoptotic bodies, chromatin condensation and nulcear blebbing in Raw 264.7 cells commending the apoptotic effect of marmelosin. Marmelosin thus displayed potential multipotent antioxidant, anti-inflammatory and anticancer properties via TNF-alpha mediated Akt signaling pathway.