Oxidative Tea Polyphenols Greatly Inhibit the Absorption of Atenolol

Abstract

Oxidative tea polyphenols (OTPs) is the oxidative polymerization product of epigallocatechin-3-O-gallate (EGCG) forms during the process of Pu-er tea fermentation, and possesses absorption property, which may absorbs on drugs thus impact the drug bioavailability when taking medicines with Pu-er tea. Here we demonstrated that OTP inhibited the absorption of atenolol in the intestine, which was determined by testing atenolol levels of plasma via high performance liquid chromatography (HPLC). After administration of atenolol (50 mg/kg), atenolol was absorbed (Tmax: 1.867 h) with the half-life (t1/2) of 6.663 h in control group; Compared with atenolol group, AUC0-t (h*ng/ml), AUC0-∞(h∗ng/ml), and Cmax of OTP+atenolol group (OTP 500 mg/kg + atenolol 50 mg/kg) reduced 38.7, 27, and 51%, respectively, the atenolol concentration of plasma was reduced by OTP approximately 43, 49, and 55.5% at 30 min, 1 and 2 h, respectively, (P < 0.01). Furthermore, the level of atenolol in feces was higher in the OTP+atenolol group, indicating that the absorption of atenolol in rats was inhibited by OTP. Isothermal titration calorimetry assay identified that EGCG can bind to atenolol and the in vitro results showed that OTP absorbed on atenolol and formed precipitate in acid condition, demonstrating a significant positive relationship between atenolol levels and OTP dosage. Taken together, these results suggested that consuming Pu-er tea with atenolol might inhibit atenolol absorption and possible other drugs.

Pu-erh Tea Extract Ameliorates Ovariectomy-Induced Osteoporosis in Rats and Suppresses Osteoclastogenesis In Vitro

“…After the post-fermentation process, the caffeine, polysaccharide, and tea pigment (theaflavin, thearubigin, and theabrownin) levels were substantially increased in Pu-erh tea ( Zhao L. et al, 2011 ; Lv et al, 2013 ). Notably, tea polyphenols have undergone a series of oxidative, condensing and degradative chemical processes to form oxidized tea polyphenols, which have many positive effects on human health ( Lv et al, 2013 ; Huang et al, 2014 ; Shan et al, 2016 ; Wang et al, 2016 ; Lu et al, 2017 ). Because of the extraordinary complexity of its components, the bioactive constituents of Pu-erh tea are largely unknown.…”

“…Tea pigments [also regarded as oxidative tea polyphenols (OTP)], including theaflavins, thearubigins, and theabrownins, were abundant in the fermented Pu-erh tea ( Zhao L. et al, 2011 ; Xie et al, 2017 ). Moreover, OTP were the major bioactive constituents in the PTE ( Huang et al, 2014 ; Shan et al, 2016 ; Wang et al, 2016 ; Lu et al, 2017 ).…”

The Influence of EGCG on the Pharmacokinetics and Pharmacodynamics of Bisoprolol and a New Method for Simultaneous Determination of EGCG and Bisoprolol in Rat Plasma

“…Further study identified the mechanism involved in the inhibition of the absorption of nadolol by EGCG through the transporter OATP1A2 which resulted in a decrease in the plasma concentration of nadolol ( 24 ). In addition, EGCG can interact with atenolol and form a precipitate under acidic conditions in vitro , resulting in the inhibition of the absorption of atenolol ( 25 ).…”

An Update on Impacts of Epigallocatechin Gallate Co-administration in Modulating Pharmacokinetics of Statins, Calcium Channel Blockers, and Beta-blockers

“…Concurrent oral administration of a single dose of 500 mg/kg EGCG and 50 mg/kg atenolol leads to a reduced AUC and C max of atenolol in SD rats. Further investigations showed that EGCG forms precipitate with atenolol and inhibits the intestinal absorption of atenolol [47].…”