Teucrium polium significantly lowers blood glucose levels acutely in normoglycemic male Wistar rats: A comparative to insulin and metformin

Abstract

Teucrium polium (commonly known as golden germander) is a herb that grows wild in the Mediterranean region. The natives commonly drink it as a tea for its medicinal reputation in alleviating ailments including diabetes mellitus. Some animal studies have supported its glucose lowering activity but the majority of these studies were uncontrolled and did not adequately assess its acute effect on blood glucose concentrations in vivo. The current study was undertaken to assess the acute glucose lowering effect of T. polium extract in vivo. We also aimed to identify some of the phytochemicals in the extract tested. A single dose of either the aqueous extract of T. polium, insulin, metformin or vehicle was injected in normoglycemic rats. Blood glucose samples were taken at set time points within the first 3.5 h of administration of each treatment. The glucose lowering potential of T. polium was compared to that of insulin and metformin. The total aqueous extract of T. polium significantly (p < 0.01) lowered blood glucose concentration with an efficacy approaching that of insulin within the first 30 min of its administration. The extract continued to lower blood glucose levels several hours following its administration and overall was more effective than metformin in lowering blood glucose over time. The total aqueous extract of T. polium lowers blood glucose levels acutely and potently. Some phytochemicals of bioactive reputation have been identified in this plant. However, the exact bioactive agent(s) and their mechanism(s) of action responsible for the glucose lowering effect are yet to be identified.

Keywords: Teucrium polium, golden germander, diabetes mellitus, antidiabetic effect, hypoglycemic potential, acute study, blood sugar levels.