title: Sweet tea leaves extract improves leptin resistance in diet-induced obese rats.
abstract: OBJECTIVE
  Dietary obesity is usually characterized by leptin resistance and abnormal lipid metabolism. Lithocarpus polystachyus Rehd.(Sweet Tea) leaf is a kind of Chinese folkloric medicine, and it has been widely used for obesity, diabetes, and hypertension in South China. The present study is aimed at investigating the pharmacological mechanism of the anti-hyperleptinaemia effects of Sweet Tea leaves extract in high fat diet-induced obese rats.
  
  
  METHODS
  We induced high fat diet obesity for 14 weeks to test the corrective effects of three ST doses (75, 150 and 300 mg/kg per day) for 8 weeks. At the end of the experiment, body weight, fasting blood glucose and serum lipids, superoxide dismutase (SOD), malondialdehyde (MDA), fasting serum insulin and leptin, C-reactive protein, adiponectin and resistin levels were measured, Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) was also calculated. mRNA gene expression of PPARγ (peroxisome proliferator-activated receptor γ) and C/EBPα(CCAAT/enhancer-binding protein α) in epididymal adipose tissue of DIO control and experimental groups were evaluated.
  
  
  RESULTS
  Sweet Tea leaves extract could significantly decrease the levels of serum lipids, attenuate body weight gain and lower circulating leptin and insulin levels, ameliorate the state of oxidative stress, raise serum adiponectin, reduce circulating CRP and resistin levels, and depress the expression of PPARγ and C/EBPα in epididymal adipose tissue of obese rats.
  
  
  CONCLUSIONS
  The present findings suggest that ST can effectively attenuate the leptin resistance at least through anti-hyperlipidemic activity and thus has the therapeutic potential in treating hyperlipidemia and hyperleptinaemia related to dietary obesity.
authors.affiliation: Shenzhen ENT Institute, Shenzhen 518172, China. azhou828@163.com
authors.forename: Cai-Jie
authors.initials: CJ
authors.lastname: Zhou
authors.forename: Song
authors.initials: S
authors.lastname: Huang
authors.forename: Jiang-Qi
authors.initials: JQ
authors.lastname: Liu
authors.forename: Shu-Qi
authors.initials: SQ
authors.lastname: Qiu
authors.forename: Fang-Yi
authors.initials: FY
authors.lastname: Xie
authors.forename: Hou-Pan
authors.initials: HP
authors.lastname: Song
authors.forename: Yi-Sheng
authors.initials: YS
authors.lastname: Li
authors.forename: Shao-Zhen
authors.initials: SZ
authors.lastname: Hou
authors.forename: Xiao-Ping
authors.initials: XP
authors.lastname: Lai
mesh_terms: D052242:Adiponectin / Q000378:metabolism; D000273:Adipose Tissue / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D001628:Beverages; D001786:Blood Glucose / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D002097:C-Reactive Protein / Q000378:metabolism; D023081:CCAAT-Binding Factor / Q000096:biosynthesis; D059305:Diet, High-Fat; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000494:pharmacology / Q000627:therapeutic use*; D029962:Fagaceae / Q000737:chemistry*; D015870:Gene Expression / Q000187:drug effects; D007328:Insulin / Q000378:metabolism / Q000494:pharmacology; D007333:Insulin Resistance; D020738:Leptin / Q000378:metabolism*; D050356:Lipid Metabolism / Q000187:drug effects; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D009765:Obesity / Q000097:blood; D047495:PPAR gamma / Q000096:biosynthesis; D018515:Plant Leaves / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D052243:Resistin / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D052242:Adiponectin; D001786:Blood Glucose; D023081:CCAAT-Binding Factor; D004365:Drugs, Chinese Herbal; D007328:Insulin; D020738:Leptin; D047495:PPAR gamma; D052243:Resistin; D008315:Malondialdehyde; D002097:C-Reactive Protein; D013482:Superoxide Dismutase