Effect of Geranium Essential Oil on Food Intake via Olfactory Stimulus / 대한이비인후과학회지

ABSTRACT

BACKGROUND AND OBJECTIVES: Recently, obesity has become one of the major health problems in our society. To overcome this problem, keeping a balance between food intake and energy expenditure is very important. Many natural substances including essential oils have been suggested for their potential effect on reducing weight. This study was performed to evaluate whether aroma inhalation of essential oil has a role in appetite regulation and works on the central nervous system through the olfactory stimulus. MATERIALS AND METHOD: Food intake was measured after 30 minutes of treatment with essential oil in overnight fasted Sprague-Dawley rats. In the control group, saline was used instead of essential oil. Changes in pro-opiomelanocortin (POMC) and neuropeptide Y (NPY) mRNA expression levels in the hypothalamus were measured following 30 minutes of treatment with geranium essential oil using real-time polymerase chain reaction. RESULTS: Of the seven essential oils, geranium significantly decreased the amount of food intake compared to the control group. Geranium essential oil significantly increased POMC mRNA expression in the hypothalamus, but did not change the NPY mRNA expression. The increased POMC mRNA expression was reversed by treatment with xylocaine, which blocks the olfactory perception. CONCLUSION: These results suggest that geranium essential oil has anorexic effect through the activation of POMC neurons in the hypothalamus via olfactory stimulus.