Chronic administration of Eucommia leaf stimulates metabolic function of rats across several organs

• Published in: British journal of nutrition 2010-12, Vol.104 (12), p.1868-1877
• Main Authors: Fujikawa, Takahiko, Hirata, Tetsuya, Wada, Atsunori, Kawamura, Naomi, Yamaguchi, Yasuyo, Fujimura, Katsuyuki, Ueda, Taro, Yurugi, Yutaka, Soya, Hideaki, Nishibe, Sansei
• Format: Article
• Language: English
• Subjects: adenosine triphosphate; Adipokines - blood; adiponectin; Adipose tissue; Adipose Tissue, White - drug effects; animal models; Animals; Anti-obesity effects; Bark; Behaviour, Appetite and Obesity; Biological and medical sciences; blood lipids; body fat; Body weight; Body Weight - drug effects; brown adipose tissue; Chronic administration; diet-related diseases; Dietary Fats - administration & dosage; Disease prevention; dose response; Dose-Response Relationship, Drug; Drug Administration Schedule; Eating - drug effects; Energy Metabolism - drug effects; Eucommia leaf; Eucommia ulmoides; Eucommiaceae - chemistry; Feeding. Feeding behavior; free fatty acids; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation - drug effects; glucose; Glucose - metabolism; Herbal medicine; human diseases; ketone bodies; Ketone Bodies - metabolism; Leaves; lipid peroxidation; liver; Liver - drug effects; Liver - enzymology; Liver - metabolism; Male; Metabolic disorders; Metabolic functions; Metabolic syndrome; muscle tissues; Nutrition research; Obesity; plant extracts; Plant Extracts - administration & dosage; Plant Extracts - chemistry; Plant Extracts - pharmacology; Plant Leaves - chemistry; Powders; Rats; Rats, Sprague-Dawley; Real-time PCR; resistin; Rodents; triacylglycerols; tumor necrosis factor-alpha; Vertebrates: anatomy and physiology, studies on body, several organs or systems; visceral fat; white adipose tissue
• ISSN: 0007-1145; 1475-2662
• DOI: 10.1017/S0007114510002965

Eucommia bark (Eucommia ulmoides Oliver) has been used as an herbal medicine, and more recently, the plant's leaves have been widely used to prepare tea which may have anti-obesity properties. We used a metabolic syndrome-like rat model, produced by feeding a 35 % high-fat diet (HFD), to examine potential anti-obesity and anti-metabolic syndrome effects and mechanisms of chronic administration of Eucommia leaf as an extract or green leaf powder. Eighty rats were studied for 3 months in ten groups. Both forms of Eucommia leaves minimised increases in body weight and visceral fat in a dose-dependent fashion. Increases in plasma levels of TAG and NEFA, and insulin resistance secondary to HFD were lessened by both forms of Eucommia leaf. Concomitantly, an increase in plasma adiponectin levels and suppression of plasma resistin and TNF-α levels were confirmed. Real-time PCR studies showed that both forms of Eucommia leaf enhanced metabolic function across several organs, including diminishing ATP production (white adipose tissue), accelerating β-oxidation (liver) and increasing the use of ketone bodies/glucose (skeletal muscle), all of which may exert anti-obesity effects under HFD conditions. These findings suggest that chronic administration of either form of Eucommia leaves stimulates the metabolic function in rats across several organs. The anti-obesity and anti-metabolic syndrome activity in this rat model may be maintained through secretion and regulation of adipocytokines that depend on the accumulation of visceral fat to improve insulin resistance or hyperlipaemia.