Absorption and pharmacokinetics of grapefruit flavanones in beagles

Abstract

The present study evaluated the pharmacokinetics of three different grapefruit flavanone forms in dog plasma and demonstrated their absorption after an oral intake of a grapefruit extract; pharmacokinetic parameters of these forms were also determined. Ten healthy beagles were administered 70 mg citrus flavonoids as a grapefruit extract contained in capsules, while two additional dogs were used as controls and given an excipient. The grapefruit flavanone naringin, along with its metabolites naringenin and naringenin glucuronide, was detected in dog plasma. Blood samples were collected between 0 and 24 h after administration of the extract. Naringin reached its maximun plasma concentration at around 80 min, whereas naringenin and naringenin glucuronide reached their maximun plasma concentrations at around 20 and 30 min, respectively. Maximum plasma concentrations of naringin, naringenin and naringenin glucuronide (medians and ranges) were 0·24 (0·05-2·08), 0·021 (0·001 -0·3) and 0·09 (0·034-0·12) mmol/l, respectively. The areas under the curves were 23·16 l (14·04 -70·62) min £ mmol/for nariningin, 1·78 (0·09 -4·95) min £ mmol/l for naringenin and 22·5 (2·74 -99·23) min £ mmol/l for naringenin glucuronide. The median and range values for mean residence time were 3·3 (1·5 -9·3), 2·8 (0·8 -11·2) and 8·0 (2·3 -13·1) h for naringin, naringenin and naringenin glucuronide, respectively. The results of the present study demonstrate the absorption of grapefruit flavanones via the presence of their metabolites in plasma, thus making an important contribution to the field since the biological activities ascribed to these compounds rely on their specific forms of absorption.

Plant Polyphenol Intake Alters Gene Expression in Canine Leukocytes

“…2.5% ME 1 3,327 kcal/kg Polyphenol extracts in capsules were orally administered twice a day (morning and afternoon) at dosages of 68 mg citrus naringin/dog/day (CE); 77 mg green tea epigallocatechin gallate (EGCG)/dog/day (GTE); 45 mg grape seed proanthocyanidins/ dog/day (GSE). Previously, bioavailability studies with green tea extract and citrus extract were conducted in beagle dogs to assure the absorption of their polyphenol compounds (data not shown) [30,31] .…”

Tissue Distribution Study of Naringin in Rats by Liquid Chromatography-Tandem Mass Spectrometry

“…To date, pharmacokinetic studies on absorption and metabolism of naringin have been extensively carried out in rats [11][12][13][14] , dogs [ 15 ] and rabbits [ 16 ] . After an oral administration of naringin, as a pure compound or as mixture, the forms detected in the circulation included native naringin as well as several major metabolites: aglycone naringenin, glucuronide and sulfate of naringenin [11][12][13][14][15][16] . However, the tissue distributions of naringin and its major metabolites in the target organs are unclear.…”

Anthocyanins as Functional Food Colors

“…OptiBerry with many berry extracts exhibited a higher oxygen radical absorbance capacity (ORAC) value, low cytotoxicity, and superior anti-angiogenic properties when compared to other combination administrations. OptiBerry was safe and antioxidative against broad (3) spectra in vivo. The acute oral 50% lethal dose (LD 50 ) of OptiBerry was greater than 5 g/kg in rats.…”

“…1). It was suggested that the stimulation of the DNA base excision repair processes might prevent mutagenic changes in the prostate cancer cells [2,3].…”

“…The inhibition of VEGF release by these flavonoids might be due in part to a novel mechanism for mammary cancer prevention. This means that anthocyanin flavanone glycosides such as naringin and rutin have been proven to be potent inhibitors of angiogenic peptide vascular endothelial growth factor, which is released from human tumor cells [3,4].…”