Increased expression of GLUT4, catalase and nitric oxide by a crystalised fraction from ethanolic extracts of oak leaf lettuce and okra seed in C2C12 cell line

Abstract

The fractions obtained from low temperature-induced crystallisation of ethanolic extracts of green- and red-oak leaf and okra seed were accounted for total polyphenol content and the DPPH antioxidant activity, resulting in 5.99, 4.44, and 12.35 mg gallic acid equivalent per g sample, and 0.45, 0.35, and 0.99 mg Trolox equivalent per g sample, respectively. Insulin resistance was the result after incubating C2C12 skeletal muscle cells in high glucose DMEM for 20 h. Oxidative stress and inflammation were triggered by re-incubating these resistant cells with insulin. The expression of p-p38 MAPK and NF-B proteins and the NF-B p65 transcription factor activity were enhanced. Such inflammatory protein markers were reduced when the crystalised extracts replaced insulin. Increased catalase activity and NO production were also determined for the incubations using the crystalised extracts. It was suitable to include these vegetables in the daily diets of prediabetic individuals for better management of the patient’s health status by increasing insulin sensitivity and decreasing inflammation.