Theaflavins, dimeric catechins, inhibit peptide transport across Caco-2 cell monolayers via down-regulation of AMP-activated protein kinase-mediated peptide transporter PEPT1

Orally administrated dipeptide Ser-Tyr efficiently stimulates noradrenergic turnover in the mouse brain

“…8) In brief, Caco-2 cell monolayers used in this study were grown in BD Falcon™ cell culture Transwell inserts (PET membrane, 0.9 cm 2 , 1.0 μm pore size; BD Biosciences) coated with type I collagen (collagen gel culturing kit, Cellmatrix type I-A, Nitta Gelatin, Osaka, Japan) at a density of 4.0 × 10 5 cell/mL and were cultured in a seeding basal medium containing MITO+™ serum extender (BD Biosciences, Franklin Lakes, NJ, USA) for 48 h. The medium was replaced with an enterocyte differentiation medium containing MITO+™ serum extender every day for three days to allow the cells to form monolayers with >100 Ω cm 2 of transepithelial electrical resistance. The monolayers grown in Transwell inserts were gently rinsed with Hanks' balanced salt solution (HBSS) buffer (pH 6.0), and mounted in the Ussing Chamber containing 7.5 mL of HBSS buffer (pH 6.0) (adjusted with 10 mM 2-(N-morpholino) ethanesulfonic acid) on the apical side and the same volume of HBSS buffer (pH 7.4) (adjusted with 10 mM 4-(2-hydroxyethyl)-1-piperazine ethanesulfonic acid) on the basolateral side.…”

Sesamol suppresses the inflammatory response by inhibiting NF-κB/MAPK activation and upregulating AMP kinase signaling in RAW 264.7 macrophages

“…In the present study, we showed that sesamol could promote AMPK activation in LPS-stimulated macrophages. Compound C, an AMPK inhibitor, inhibited AMPK phosphorylation [43]. We found that, in the presence of Compound C, sesamol could recover AMPK activation in macrophages.…”

“…AMPK could inhibit acetylCoA carboxylase activity to decrease lipid synthase [43]. Recent studies found that AMPK activation also decreased inflammatory responses in patients with metabolic syndrome [13].…”

Condensed catechins and their potential health-benefits

“…In Caco-2 transport experiments, theaflavin-3′-O-gallate (TF3′G) was not detected from the apical to basolateral side after 60 mintransport experiments by mass spectrometry (MS), whereas MSdetectable transport from the basolateral to apical side was observed ( Fig. 2) (Takeda et al, 2013), which led to physiological potentials at the intestinal membrane, similar to quercetin (Suzuki and Hara, 2011) (further discussion will be done in the later Section 3). Considering these reports, theaflavins could be categorized as non-absorbable food compounds.…”

“…An LC-TOF-MS chromatogram of theaflavins was obtained from Caco-2 cell transport experiments, in which transport of 1 mM TF3′G across Caco-2 cell monolayers for 60 min was performed, and solutions obtained at apical and basolateral sides analyzed by MS in negative ionization mode. The MS chromatogram with no TF3′G peak at basolateral side was cited from the report by Takeda et al (2013). Shoji et al (2006) reported that procyanidins from dimers to pentamers were detected in the blood after a single oral administration in 7-week-old male Wistar rats, whereas the magnitude of absorption by oligomers remains uncertain.…”