title: Glycyrrhizic acid prevents high calorie diet-induced metabolic aberrations despite the suppression of peroxisome proliferator-activated receptor γ expression.
abstract: OBJECTIVE
  To investigate the effects of glycyrrhizic acid supplementation on glucose and lipid metabolism in rodents consuming a high-fat, high-sucrose diet.
  
  
  METHODS
  Twenty-four male, 8-week old Sprague Dawley rats with an initial weight of 160 to 200 g were randomised into three groups (n = 6 for each group): groups A (standard rat chow), B (high-fat, high-sucrose diet), and C (high-fat, high-sucrose diet + 100 mg/kg/d of glycyrrhizic acid via oral administration). The rats were treated accordingly for 4 wk. Glycaemic parameters, lipid profile, stress hormones, and adiponectin levels were measured after the treatment. Relative gene expressions of peroxisome proliferator-activated receptor α and γ, lipoprotein lipase as well as gluconeogenic enzymatic activities in different tissues were also determined.
  
  
  RESULTS
  Consumption of high-fat, high-sucrose diet triggered hyperglycaemia, insulin resistance, and dyslipidemia, which were effectively attenuated by supplementation with glycyrrhizic acid. Glycyrrhizic acid supplementation also effectively reduced circulating adrenaline, alleviated gluconeogenic enzymes overactivity, and promoted the upregulation of lipoprotein lipase expression in the cardiomyocytes and skeletal muscles. A high calorie diet also triggered hypoadiponectinaemia and suppression of peroxisome proliferator-activated receptor γ expression, which did not improve with glycyrrhizic acid treatment.
  
  
  CONCLUSIONS
  Supplementation with glycyrrhizic acid could alleviate high calorie diet-induced glucose and lipid metabolic dysregulations by reducing circulatory stress hormones, normalizing gluconeogenic enzyme activities, and elevating muscular lipid uptake. The beneficial effects of these bioactivities outweighed the adverse effects caused by diet-induced repression of peroxisome proliferator-activated receptor γ expression, resulting in the maintenance of lipid and glucose homeostasis.
authors.affiliation: School of Science, Monash University Malaysia, Selangor Darul Ehsan, Malaysia. Electronic address: hsche19@student.monash.edu.
authors.forename: Hong Sheng
authors.initials: HS
authors.lastname: Cheng
authors.affiliation: School of Science, Monash University Malaysia, Selangor Darul Ehsan, Malaysia.
authors.forename: Hui Ping
authors.initials: HP
authors.lastname: Yaw
authors.affiliation: School of Science, Monash University Malaysia, Selangor Darul Ehsan, Malaysia.
authors.forename: So Ha
authors.initials: SH
authors.lastname: Ton
authors.affiliation: School of Science, Monash University Malaysia, Selangor Darul Ehsan, Malaysia.
authors.forename: Siew Mei
authors.initials: SM
authors.lastname: Choy
authors.affiliation: School of Science, Monash University Malaysia, Selangor Darul Ehsan, Malaysia.
authors.forename: Joana Magdelene Xiao Fang
authors.initials: JM
authors.lastname: Kong
authors.affiliation: School of Medicine and Health Sciences, Monash University Malaysia, Selangor Darul Ehsan, Malaysia.
authors.forename: Khalid
authors.initials: K
authors.lastname: Abdul Kadir
mesh_terms: D052242:Adiponectin / Q000097:blood; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000097:blood / Q000494:pharmacology*; D059305:Diet, High-Fat / Q000009:adverse effects*; D004041:Dietary Fats / Q000008:administration & dosage; D004837:Epinephrine / Q000097:blood; D005943:Gluconeogenesis / Q000187:drug effects; D019695:Glycyrrhizic Acid / Q000097:blood / Q000494:pharmacology*; D008071:Lipoprotein Lipase / Q000097:blood / Q000187:drug effects; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood / Q000517:prevention & control*; D047495:PPAR gamma / Q000037:antagonists & inhibitors* / Q000097:blood; D051381:Rats; D017207:Rats, Sprague-Dawley; D013395:Sucrose / Q000008:administration & dosage*
chemical_list: D052242:Adiponectin; D000893:Anti-Inflammatory Agents; D004041:Dietary Fats; D047495:PPAR gamma; D013395:Sucrose; D019695:Glycyrrhizic Acid; D008071:Lipoprotein Lipase; D004837:Epinephrine
keywords: Adiponectin; Adrenaline; Gluconeogenesis; Glycyrrhizin; Lipoprotein lipase; Metabolic syndrome