Bioassay-guided antidiabetic potentials of Devil’s club (Oplopanax horridus) preparations from the traditional pharmacopeia of the Squamish and other first nations of British Columbia
An ethnobotanical approach has been used to identify medicinal plant species used by Canadian First Nations to treat Type 2 diabetes (T2D) symptoms. Devil's Club (Oplopanax horridus (Sm.) Miq.) was identified as one of these plants reported to possess anti-diabetic properties. The aim of this Masters thesis was to evaluate Devil’s club inner bark potential stimulation of glucose transport in C2C12 cells and inhibition of G6Pase enzyme in H4IIE hepatocytes using in vitro bioassays. Different preparations of devil’s club were used. Traditional preparations of medicinal plants are often made with hot water, so a hot water extract of the plant was used to mimic the traditional methods. Also, 80% ethanol extract of the plant was used to maximize the extraction of plant compounds. Other fractions prepared with solvents of increasing polarity (Hexanes, dichloromethane –DCM, ethyl acetate, methanol, water) and a pure compound (chlorogenic acid) were used to begin unraveling devil’s club active compounds. The results of this study showed that ethanol extract, DCM, and hexanes fractions significantly stimulated glucose transport in C2C12 cells after 18 h incubation with stimulation percentages of 204±4%, 201±14%, and 197±8% above DMSO vehicle control, respectively. Meanwhile, a statistical significant inhibition in glucose-6-phosphatase (G6Pase) activity (-24±4% compared with vehicle control) was observed when DCM fraction was tested. Hence, with respect to glucose homeostasis, the results confirmed that several preparations of devil’s club inner bark significantly stimulated muscle glucose transport and inhibited hepatic G6Pase activity. Further studies using the phytochemical fractionation approach are needed to isolate compounds and compare them together with their mixtures to enable better understanding of the synergistic and antagonistic effect and to understand the plant’s mechanisms of action and molecular targets.
G6Pase Type 2 diabetes Glucose transport Traditional medicine Glucose homeostasis Natural health products