Stimulation of glucose uptake by theasinensins through the AMP-activated protein kinase pathway in rat skeletal muscle cells

Effects of Microbial Metabolites of (−)-Epigallocatechin Gallate on Glucose Uptake in L6 Skeletal Muscle Cell and Glucose Tolerance in ICR Mice

“…26) This evaluation was according to the procedure used for other dietary polyphenols. [27][28][29] Serumstarved L6 myotubes in a 96-well plate were treated with 11 kinds of metabolites dissolved with dimethyl sulfoxide (DMSO) at a final concentration of 3 µM for 4 h in 0.2% (w/v) BSA/MEM. Insulin at 100 nM was used as a positive control, and DMSO was used as a vehicle control.…”

Condensed catechins and their potential health-benefits

“…abolish the increased phosphorylation of AMPK by theasinensins (Fig. 4, Qiu et al, 2014). Thus, theasinensins can be categorized as anti-diabetic condensed catechins that can stimulate Glut4 translocation via the CAMKK/AMPK signalling pathway in an insulinindependent manner in skeletal muscle.…”

“…The IRS pathway leads to activation of kinases dependent on PI3K, 3-phosphoinositide-dependent protein kinase-1 (PDK-1), and its down-stream effectors, namely atypical protein kinase C (PKC) isoforms and protein kinase B (PKB; Akt) (Bandyopadhyay et al, 2001). However, the promotion of glucose uptake by theasinensins was not altered by insulin and wortmmanin (a PI3K inhibitor), revealing the possibility that the insulinindependent pathway, not the IR/PI3K/Akt pathway, is the main mechanism underlying theasinensin-induced glucose uptake (Qiu et al, 2014).…”

“…2, Qiu et al, 2012) on glucose uptake in muscle. It has been reported that TSA (a dimer of EGCG) demonstrated a potent promoting effect on glucose uptake in skeletal muscle cells (L6 myotubes) (Qiu et al, 2014). The lack of effect of EGC and EC suggests that the galloyl group in theasinensins may be the group involved, although the power of TSA was still estimated to be ca.…”

“…In LKB-1-knockdown L6 myotubes (0.1 μM siRNA targeted against LKB1), a significant enhancement of AMPK phosphorylation by TSA (50 μM, 60 min) was observed (P o0.05 by unpaired Student's t-test, n¼ 4). The data were cited from the report by Qiu et al (2014). abolish the increased phosphorylation of AMPK by theasinensins (Fig.…”