The Ginkgo biloba extract on healthy geriatric dog’s diet

The standardized extract of Ginkgo biloba leaf is one of the most frequently used phytomedicines in elderly persons. G. biloba contains flavonoids, of which quercetin is recognized as the most important. Flavonoids show potent antioxidant and free-radical scavenging activities. In this study, the presence of G. biloba extract added to a senior dry diet at the end of food production was determined by liquid chromatography–mass spectrometry/ mass spectrometry (LC-MS/MS). Diet A (without G. biloba) and diet B (with G. biloba) were administered to a group of 11 healthy aging dogs for 1 month. The ration was calculated on the basis of ideal weight. No other food was administered, but water was provided. Absorption and efficacy trials were performed by blood collection of all subjects every 10 days. G. biloba absorption by dogs was investigated by determination of plasma quercetin after meals by LC-MS/MS. Two oxidative stress parameters, derivatives–reactive oxygen species (d-ROMs) and biologic antioxidant potential (BAP) (Diacron International, GR, Italy), were spectrophotometrically assessed in dog plasma. BAP and d-ROMs data were analyzed by analysis of variance and Tukey-Kramer tests; BAP and quercetin values were tested by correlation test. Differences were considered significant when P <.05. G. biloba absorption was verified by an increase in plasma quercetin values after diet B administration (9.08 ± 6.04 ng/ml). No significant variation of d-ROMs values occurred, but the BAP was considerably increased in the sample on the last day (3,508 μmol/L) in contrast to the first sampling day (2,537 μmol/L). Plasmatic BAP and quercetin concentrations were correlated (r =0.73). These results confirmed the utility of G. biloba administration to healthy geriatric dogs to improve their antioxidant potential, which is so important during senescence.