Planta Med 2008; 74 - PA197
DOI: 10.1055/s-0028-1084195

Screening for anti-diabetic activity of medicinal plant extracts from the Canadian Boreal Forest

D Harbilas 1, 2, 3, LC Martineau 1, 2, 3, CS Harris 4, 5, DCA Adeyiwola-Spoor 1, 2, 3, A Saleem 4, T Johns 6, A Cuerrier 7, JT Arnason 4, SAL Bennett 5, PS Haddad 1, 2, 3
  • 1Department of Pharmacology, Université de Montréal, P.O. Box 6128, Centre-ville Station, Quebec, H3C 3J7, Canada
  • 2Nutraceuticals and Functional Foods Institute, Université Laval, Quebec, G1K 7P4, Canada
  • 3Montreal Diabetes Research Center, 2901 Rachel Est, Quebec, H1W 4A4, Canada
  • 4Department of Biology and Center for Research in Biopharmaceuticals and Biotechnology, University of Ottawa, Ontario, K1N 6N5, Canada
  • 5Neural Regeneration Laboratory, Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ontario, K1H 8M5, Canada
  • 6School of Dietetics and Human Nutrition, Macdonald Campus, McGill University, Ste. Anne de Bellevue, Quebec, H9X 3V9, Canada
  • 7Plant Biology Research Institute, Montreal Botanical Garden, Université de Montréal, Quebec, H1X 2B2, Canada

Among the Cree of Northern Quebec, there is a disproportionately high rate of diabetic complications due to the cultural inadequacy of modern type II diabetes therapies. In order to establish culturally adapted anti-diabetic treatments, our team identified several candidate plant species used by the Cree to treat symptoms of diabetes. An initial study focused on 8 species and revealed that most possess significant in vitro anti-diabetic activity. The purpose of the present study was to assess a further 9 species identified through the ethnobotanical survey. Crude plant extracts were screened for: 1) potentiation of basal and insulin-stimulated glucose uptake by skeletal muscle cells (C2C12) and adipocytes (3T3-L1); 2) potentiation of glucose-stimulated insulin secretion by pancreatic β-cells (βTC); 3) potentiation of adipogenesis in 3T3-L1 cells; 4) protection against glucose toxicity and deprivation in PC12-AC neuronal precursor cells; and 5) diphenylpicrylhydrazyl (DPPH) oxygen free-radical scavenging. Four species potentiated basal glucose uptake in C2C12s or 3T3-L1s, one being as potent as metformin. Adipogenesis was accelerated by four species with a potency roughly half that of rosiglitazone. Five species protected PC12-AC cells against glucose toxicity and 4 protected against glucose deprivation. Five species exhibited anti-oxidant activity comparable to ascorbic acid. However, no species increased insulin secretion. The present study revealed that several plants exhibit a promising profile of anti-diabetic potential. Such profiles are varied and can be used to inform the rational choice of plants for more in depth evaluation. Such profiles also confirm the validity of our novel ethnobotanical approach.

Acknowledgement: Funded by the CHIR