The present findings showed that administration of baicalein decreased pP38MAPK, pERK and PPARγ levels, but enhanced pAKT, PGC-1α and UCP1 contents as well as GLUT4 expression in adipocytes, and reversed high fat diet-induced glucose intolerance, hyperglycemia and insulin resistance in diet-induced obese mice.
T<sub>4</sub> attenuated glucose intolerance by 15% and decreased IR index (IRI) by 34% in T<sub>4</sub>-treated OLETF compared to untreated OLETF despite a 31% decrease in muscle Glut4 mRNA expression.
These results strongly suggest that fermented tea activates both PI3K/Akt- and AMPK-dependent signaling pathways to induce GLUT4 translocation and increases the expression of insulin receptor to improve glucose intolerance.
Skeletal muscle GLUT 4 expression is normal in obesity, impaired glucose tolerance (IGT), GDM, and NIDDM, indicating that functional activity or translocation of GLUT 4 may be impaired.4.
However, in vastus lateralis, relative amounts of GLUT4 per milligram membrane protein were similar (NS) among lean (1.0 +/- 0.2) and obese (1.5 +/- 0.3) subjects and patients with IGT (1.4 +/- 0.2) and NIDDM (1.2 +/- 0.2).