Uptake of grape anthocyanins into the rat kidney and the involvement of bilitranslocase

Abstract

Anthocyanins are among the most common flavonoids in the human diet. In spite of their very low bioavailability, anthocyanins are indicated as active in preventing the progress of cardiovascular and neurodegenerative diseases, obesity, inflammation, and cancer. Any piece of knowledge concerning absorption, tissue distribution, metabolism, and excretion of dietary anthocyanins is expected to help understanding the apparent paradox between their low concentrations in cells and their bioactivity. The aim of this work was to investigate the renal uptake of dietary anthocyanins and the underlying molecular mechanism. A solution containing anthocyanins extracted from grape (Vitis vinifera) was introduced into the isolated stomach of anesthetized rats; after both 10 and 30 min, plasma, liver, and kidney were analyzed for their anthocyanin contents. While anthocyanins in the liver were at apparent equilibrium with plasma both after 10 and 30 min, kidney anthocyanins were 3- and 2.3-fold higher than in plasma, after 10 and 30 min, respectively. Since the transport activity of the bilitranslocase in kidney basolateral membrane vesicles was competitively inhibited by malvidin 3-glucoside (K(i) = 4.8 +/- 0.2 microM), the anthocyanin uptake from blood into kidney tubular cells is likely to be mediated by the kidney isoform of this organic anion membrane transporter.

Tissue bioavailability of anthocyanins from whole tart cherry in healthy rats

“…The mechanisms of anthocyanin cellular transport are postulated to include bilitranslocase and the ATP-binding cassette (ABC) family (Schinkel & Jonker, 2003;Vanzo et al, 2008). Since it is not clear from the current preliminary study how variation in anthocyanin accumulation among tissues is affected by the varied tissue expression of these transporters, this topic deserves further study.…”

“…For example, grape anthocyanins appear in the kidneys of rats 10 min after gastric administration, where the total concentration was almost two times higher than in the systemic circulation (Vanzo et al, 2008). Anthocyanin-rich diets have conferred protection to kidneys from experimental hypertension (Elks et al, 2011) and diabetes (Kang, Lim, Lee, Yeo, & Kang, 2013).…”

“…Finally, some of the proposed transporters for anthocyanins may have diverse structural preferences or affinities, and these transporters may vary by tissue type (Schinkel & Jonker, 2003;Vanzo et al, 2008).…”

Expression and Function of Renal Organic Anion Transporters in Cholestasis

“…Bilitranslocase has been indicated as the protein responsible for the electrogenic hepatic uptake of cholephilic organic anions, such as bromosulfophtalein (BSP) and thymol blue, the tetrapyrrole bilirubin, and flavonoids (the anthocyanin malvidin 3-glucoside and the flavonol quercetin) (Passamonti et al 2009). Bilitranslocase has also been detected in basolateral plasma membranes from kidney cells and it has been demonstrated to be involved in the renal transport of BSP, bilirubin and anthocyanins (Elías et al, 1990;Vanzo et al, 2008). In this way, bilitranslocase contributes to the hepatic and renal elimination of exogenous organic anions (such as BSP), endogenous metabolites (such as bilirubin) and anthocyanins (flavonoid-based pigments that are present in many fruits and vegetables in the human diet, which have been reported to be positively implicated in human health (Vanzo et al, 2008;Passamonti et al 2009)).…”

Expression of Kidney and Liver Bilitranslocase in Response to Acute Biliary Obstruction

“…Bilitranslocase has also been detected in basolateral plasma membranes from kidney cells and has been demonstrated to be involved in the renal transport of BSP, bilirubin and anthocyanins [11,22]. In this way, bilitranslocase contributes to the hepatic and renal elimination of exogenous organic anions (such as BSP), endogenous metabolites (such as bilirubin) and anthocyanins (flavonoid-based pigments that are present in many fruits and vegetables in the human diet, which have been reported to be positively implicated in human health [22]).…”