|Title||Antidiabetic Activity of Extracts from Needle, Bark, and Cone of Picea glauca: Organ-Specific Protection from Glucose Toxicity and Glucose Deprivation|
|Year of Publication||2008|
|Authors||Harris CS, Lambert J, Saleem A, Coonishish J, Martineau LC, Cuerrier A, Haddad PS, Arnason JT, Bennett SAL|
|Keywords||Anti Diabetic Plant Project|
The incidence of type 2 diabetes mellitus has reached epidemic proportions worldwide. Canadian aboriginal communities, particularly theCreeNation of Eeyou Istchee, have been identified as a high-risk population. Culturally
acceptable treatment options are limited notably for diabetic complications resulting in peripheral neuropathy. Here, we describe results of an ongoing collaborative research
project with Cree of Eeyou Istchee to identify botanicals capable of protecting peripheral neuronal precursors from glucose toxicity and glucose deprivation in vitro. Polar
fractions of three plant organs (needles, cone, and bark) collected from Picea glauca (Moench) Voss (Pinaceae), were tested for toxicity under normoglucose, glucotoxicity,
and glucose deprivation conditions. The profile of phenolic metabolites in each extract was first characterized by high-performance liquid chromatography-diode array
detection-atmospheric pressure chemical ionisation mass spectrometry (HPLC-DAD-APCI/MS). We report here that these fractions are well-tolerated by PC12 neuronal
precursors under normoglucose conditions. LD50 concentrations of needle extracts exceeded 100 μg/mL, whereas the LD50 of bark and cone extracts was 40 and 36.4
μg/mL, respectively. We further show that the cytoprotective properties of minhikw after glucose challenge are concentration-dependent and organ-specific. Needle
extracts protected PC12 cells from both glucotoxicity and glucose deprivation. Bark extracts had negligible activity. Cone extracts further impaired PC12 cell glucose tolerance.
This study provides the first validation of antidiabetic activity of minhikw organs at the cellular level relevant to the management of diabetic peripheral neuropathy.