Non-polar solvent fractions of Oplopanax horridus stimulate muscle glucose uptake and inhibit hepatocellular glucose-6-phosphatase enzyme activity

Canadian First Nation (FN) populations exhibit a higher prevalence of obesity and Type 2 diabetes than non-Indigenous Canadians. Moreover, modern treatments are not culturally well adapted and several FN wish to explore the benefits of their Traditional Medicine. British Columbia FN (notably, Squamish) use Oplopanax horridus (OH) or Devil's club for health benefits, including for diabetes. We studied the antidiabetic potential of OH on muscle glucose transport and hepatocellular glucose homeostasis. Methodology: A classical bioassay-guided phytochemical fractionation approach was used to identify potential solvent fractions responsible of the antidiabetic actions of OH. Differentiated C2C12 myocytes were treated with the following OH preparations: hot water (HWE) and ethanol (EtOH) crude extracts (12.5 µg/ml); specific solvent fractions: hexanes (HEX; 1.12 µg/ml); dichloromethane (DCM), ethyl acetate (EtOAc), methanol (MeOH), water (H2O) as well as chlorogenic acid (CA) (all 12.5 µg/ml). Radiolabelled glucose uptake was measured. H4IIE (rat hepatoma cells) were treated with the same OH preparations and glucose-6-phosphatase (G6Pase) activity measured. Results: EtOH extract, as well as HEX, DCM, EtOAc fractions significantly stimulated muscle glucose uptake by 130 – 204%, compared to DMSO control (set at 100%). In contrast, only DCM fraction significantly inhibited hepatocellular G6Pase activity (24%). Other preparations mildly reduced G6Pase (12 – 17%). Conclusion: These results suggest an antidiabetic potential of Oplopanax horridus in liver and skeletal muscle cells in culture. The phytochemical fractionation approach will be pursued further to identify specific compounds contained in OH preparations that contribute to its antidiabetic potential.

Please note: this abstract was changed according to the following erratum: the name of the second author was changed.

No conflict of interest has been declared by the author(s).