Intestinal Absorption of p-Coumaric and Gallic Acids in Rats after Oral Administration

Abstract

Ferulic acid (FA) and p-coumaric acid (CA) are absorbed by the monocarboxylic acid transporter (MCT) in Caco-2 cells, although gallic acid (GA) is not. Therefore, the MCT is selective for certain phenolic acids. Absorption of orally administered CA and GA in rats was studied to obtain serum pharmacokinetic profiles and to investigate their intestinal absorption characteristics in vivo. Rats were administered 100 micromol/kg body weight of CA and GA, and blood was collected from the portal vein and abdominal artery after administration. CA, GA, and their metabolites were quantified with a highly selective and sensitive coulometric detection method using high-performance liquid chromatography-electrochemical detection. Ingested CA was rapidly absorbed in the gastrointestinal tract in an intact form. The serum concentration of intact CA in the portal vein peaked 10 min after dosing (C(max) was 165.7 micromol/L). In contrast, GA was slowly absorbed, with a t(max) for intact GA of 60 min and a C(max) of 0.71 micromol/L. The area under the curve for intact CA and GA was calculated from the serum concentration profile in the portal vein to be 2991.3 and 42.6 micromol min L(-)(1), respectively. The relative bioavailability of CA against GA was about 70. This is the first demonstration that absorption efficiency of CA is much higher than that of GA in vivo. The absorption characteristics of CA are clearly different from those of GA. These findings are in good agreement with the results obtained in vitro using a Caco-2 cell system.

Tannic Acid Is a Natural β-Secretase Inhibitor That Prevents Cognitive Impairment and Mitigates Alzheimer-like Pathology in Transgenic Mice

“…For example, hydrolysable tannins are degraded to gallic acid, pyrogallol, phloroglucinol, and finally to acetate and butyrate via sequential enzymatic action (29). In particular, oral administration of gallic acid led to intestinal absorption over a period of ϳ60 min in rodents (69), which equated to 76 min in humans (70). Flavonoids including gallate have also been shown to cross into the brain in rodents (68,71,72).…”

Induction of caspase-dependent apoptosis in melanoma cells by the synthetic compound (E)-1-(3,4-dihydroxyphenethyl)-3-styrylurea

“…Specifically, phenolic acids can be absorbed through the intestine by an active transport system whereupon they can prevent oxidative stress (18,19). In addition, compounds containing one or more aromatic hydroxyl groups replace α-tocopherol as a chain-breaking anti-oxidant and restore reduced glutathione as a protective agent in cells (15).…”

Effects of pomegranate seed oil and fermented juice polyphenols fraction in different solvents on copper-induced LDL oxidation

“…As we expected alphatocopherol at low concentration could significantly prevent the LDL oxidation and delay the lag phase for about 267 min. Protective effect of alpha-tocopherol against copper-induced oxidation of LDL has been shown previously (Konishi, Hitomi, & Yoshioka, 2004). It has been revealed that alpha-tocopherol could have such an inhibitory effect through acting as a scavenger for the chain-carrying lipid peroxyl radicals and thus terminating the lipid peroxidation (Zhang, Chen, Yang, Chen, & Ying, 2014).…”

“…However, there is possibility of absorption of some of polyphenolic compounds in gastrointestinal tract without any metallization. For instance, gallic and ellagic acids that have been mentioned as effective antioxidants in pomegranate juice can be directly absorbed by intestinal tract and increase the corresponding circulation levels (Konishi et al, 2004;Zhang et al, 2014). It has been reported that the maximum concentration (C max ) of gallic acid in human plasma following oral administration of 50 mg galic acid was about 0.3 mg/L (Shahrzad & Bitsch, 1998).…”