Evaluation of the antidiabetic potential of selected medicinal plant extracts from the Canadian boreal forest used to treat symptoms of diabetes: part II.
Among the Cree of northern Quebec, the disproportionately high rate of diabetic complications is largely due to the cultural inadequacy of modern therapies for type 2 diabetes. To establish culturally adapted antidiabetic 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 antidiabetic 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 (i) potentiation of basal and insulin-stimulated glucose uptake by skeletal muscle cells (C2C12) and adipocytes (3T3-L1); (ii) potentiation of glucose-stimulated insulin secretion by pancreatic beta cells (betaTC); (iii) potentiation of adipogenesis in 3T3-L1 cells; (iv) protection against glucose toxicity and glucose deprivation in PC12-AC neuronal precursor cells; and (v) diphenylpicrylhydrazyl (DPPH) oxygen free radical scavenging. Four species potentiated basal glucose uptake in muscle cells or adipocytes, one species being as potent as metformin. Adipogenesis was accelerated by 4 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 antioxidant activity comparable to ascorbic acid. However, no species increased insulin secretion. The present study revealed that Gaultheria hispidula, Rhododendron tomentosum, and Vaccinium vitis-idaea exhibit a promising profile of antidiabetic potential and are good candidates for more in-depth evaluation.
Harbilas
Despina
D
Department of Pharmacology, Université de Montréal, Centre-ville Station, Montréal, QC H3C 3J7, Canada.
Martineau
Louis C
LC
Harris
Cory S
CS
Adeyiwola-Spoor
Danielle C A
DC
Saleem
Ammar
A
Lambert
Jennifer
J
Caves
Dayna
D
Johns
Timothy
T
Prentki
Marc
M
Cuerrier
Alain
A
Arnason
John T
JT
Bennett
Steffany A L
SA
Haddad
Pierre S
PS
D041721:3T3-L1 Cells; D017667:Adipocytes / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D019610:Cytoprotection / Q000187:drug effects; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy* / Q000208:ethnology; D004305:Dose-Response Relationship, Drug; D005609:Free Radicals / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D006801:Humans; D007004:Hypoglycemic Agents / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D007198:Indians, North American; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D016716:PC12 Cells; D010936:Plant Extracts / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D010946:Plants, Medicinal / Q000145:classification; D011792:Quebec / Q000453:epidemiology; D051381:Rats; D014197:Trees
D005609:Free Radicals; D007004:Hypoglycemic Agents; D007328:Insulin; D010936:Plant Extracts; D005947:Glucose