In VitroEvaluations of Cytotoxicity of Eight Antidiabetic Medicinal Plants and Their Effect on GLUT4 Translocation

Abstract

Despite the enormous achievements in conventional medicine, herbal-based medicines are still a common practice for the treatment of diabetes.Trigonella foenum-graecum,Atriplex halimus,Olea europaea,Urtica dioica,Allium sativum,Allium cepa,Nigella sativa, andCinnamomum cassiaare strongly recommended in the Greco-Arab and Islamic medicine for the treatment and prevention of diabetes. Cytotoxicity (MTT and LDH assays) of the plant extracts was assessed using cells from the liver hepatocellular carcinoma cell line (HepG2) and cells from the rat L6 muscle cell line. The effects of the plant extracts (50% ethanol in water) on glucose transporter-4 (GLUT4) translocation to the plasma membrane was tested in an ELISA test on L6-GLUT4myc cells. Results obtained indicate thatCinnamomon cassiais cytotoxic at concentrations higher than 100 μg/mL, whereas all other tested extracts exhibited cytotoxic effects at concentrations higher than 500 μg/mL. Exposing L6-GLUT4myc muscle cell to extracts fromTrigonella foenum-graecum,Urtica dioica,Atriplex halimus, andCinnamomum verumled to a significant gain in GLUT4 on their plasma membranes at noncytotoxic concentrations as measured with MTT assay and the LDH leakage assay. These findings indicate that the observed anti-diabetic properties of these plants are mediated, at least partially, through regulating GLUT4 translocation.