Background: Naringenin is a bioactive flavonoid found in grapes and citrus fruits including tangelo, blood orange, lemons, and tangerines. The aims of this study were to investigate the ability of naringenin to scavenge free radicals and determine its ability to protect animals from streptozotocin (STZ) -induced liver damage.

Methods: The free radical-scavenging activity of naringenin was evaluated by in vitro cell-free assay systems. In animals, the antioxidant potential of orally administered 50 and 100 mg/kg body weight naringenin for 45 days was assessed by measuring TBARS, lipid hydroperoxides, SOD, catalase, GST, GPx, and glutathione levels in liver homogenates prepared from animals injected intraperitoneally with multiple low dose streptozotocin at 50 mg/kg for five consecutive days. The extent of cellular damage caused by STZ administration was analyzed using H & E staining.

Results: Naringenin showed potent free radical scavenging activity in vitro. Naringenin effectively neutralized (a) hydroxyl radicals, (b) superoxide, (c) hydrogen peroxide, (d) nitric oxide radical, (e) DPPH, and (f) lipid peroxidation. In animals, administration of naringenin reduced lipid peroxidation and increased antioxidant levels. Analysis of liver sections showed the restoration of normal morphology upon treatment with naringenin.

Conclusions: Naringenin helps to mitigate STZ-induced liver complications by promoting antioxidant defence enzyme activities and increasing glutathione levels.