Anti-diabetic effects of lemon balm ( Melissa officinalis) essential oil on glucose- and lipid-regulating enzymes in type 2 diabetic mice.
The antioxidant activity of lemon balm (Melissa officinalis) essential oil (LBEO) on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and its hypoglycaemic effect in db/db mice were investigated. LBEO scavenged 97 % of DPPH radicals at a 270-fold dilution. Mice administered LBEO (0.015 mg/d) for 6 weeks showed significantly reduced blood glucose (65 %; P < 0.05) and TAG concentrations, improved glucose tolerance, as assessed by an oral glucose tolerance test, and significantly higher serum insulin levels, compared with the control group. The hypoglycaemic mechanism of LBEO was further explored via gene and protein expression analyses using RT-PCR and Western blotting, respectively. Among all glucose metabolism-related genes studied, hepatic glucokinase and GLUT4, as well as adipocyte GLUT4, PPAR-gamma, PPAR-alpha and SREBP-1c expression, were significantly up-regulated, whereas glucose-6-phosphatase and phosphoenolpyruvate carboxykinase expression was down-regulated in the livers of the LBEO group. The results further suggest that LBEO administered at low concentrations is an efficient hypoglycaemic agent, probably due to enhanced glucose uptake and metabolism in the liver and adipose tissue and the inhibition of gluconeogenesis in the liver.
Chung
Mi Ja
MJ
Division of Food Bioscience and Technology, College of Life Sciences and Biotechnology, Korea University, Seoul 136-713, Korea.
Cho
Sung-Yun
SY
Bhuiyan
Muhammad Javidul Haque
MJ
Kim
Kyoung Heon
KH
Lee
Sung-Joon
SJ
D000818:Animals; D001786:Blood Glucose / Q000187:drug effects*; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy / Q000201:enzymology*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D005941:Glucokinase / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D005951:Glucose Tolerance Test; D051246:Glucose Transport Proteins, Facilitative / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D005952:Glucose-6-Phosphatase / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D007328:Insulin / Q000097:blood; D050356:Lipid Metabolism / Q000187:drug effects*; D031334:Melissa / Q000737:chemistry*; D051379:Mice; D009822:Oils, Volatile / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D047492:Peroxisome Proliferator-Activated Receptors / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D010729:Phosphoenolpyruvate Carboxykinase (GTP) / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D008517:Phytotherapy; D010938:Plant Oils / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D051780:Sterol Regulatory Element Binding Protein 1 / Q000187:drug effects / Q000235:genetics / Q000378:metabolism
D001786:Blood Glucose; D051246:Glucose Transport Proteins, Facilitative; D007328:Insulin; D009822:Oils, Volatile; D047492:Peroxisome Proliferator-Activated Receptors; D010938:Plant Oils; D051780:Sterol Regulatory Element Binding Protein 1; D005941:Glucokinase; D005952:Glucose-6-Phosphatase; D010729:Phosphoenolpyruvate Carboxykinase (GTP)