Abstract
Some research indicates that cinnamon bark powder may possess blood glucose-modulating properties, but little research has been done on the volatile oil. This study examined cinnamon bark essential oil, as well as a blend of essential oils (including cinnamon bark, turmeric, cumin, and lemon balm) that may also have glucose-modulating properties, using in silico, in vitro, and in vivo techniques. In silico modeling suggested that the proposed essential oils may influence glucose metabolism via interaction with PTP1B, glucokinase, ⍺-amylase, ⍺-glucosidase, and PPAR-𝛄 receptors. In vitro studies showed that essential oils are metabolized by both cytochrome P450 (Phase I) and UGT (Phase II) enzymes in human hepatocyte microsomes, and constituents have intrinsic clearance estimates of about 2 – 22 μL/min/mg of protein. Preliminary in vivo human studies demonstrated pharmacokinetic estimates of bioavailability and half-life of some of the main constituents of cinnamon bark essential oil. Additional double-blind, randomized, placebo controlled clinical studies showed that the oils posed no significant safety hazard in the short term, and in some cases lowered fasting glucose and insulin levels in participants, though statistical significance was not achieved. Future research directions should further characterize interaction between glucose metabolic pathways and essential oils, as well as testing various dosage levels and postprandial glucose response.