Long-term baicalin administration ameliorates metabolic disorders and hepatic steatosis in rats given a high-fat diet.
OBJECTIVE
Baicalin, one of the major flavonoids in Scutellaria baicalensis, possesses antioxidant and anti-inflammatory properties. However, the effects of baicalin on metabolic disorders and hepatic steatosis have not been investigated.


METHODS
Body weight was examined in high-fat diet (HFD)-fed rats with or without baicalin treatment. At the end of the experiment, serum biochemical parameters, liver histology and lipid profile were analyzed to assess whether the animals were suffering from metabolic disorders or hepatic steatosis. In the liver, the phosphorylation of AMP activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) and the gene expression of some enzymes involved in lipogenesis were examined. The effects of baicalin on the phosphorylation of AMPK and lipid accumulation induced by high glucose in human hepatoma HepG2 cells were also examined.


RESULTS
Baicalin (80 mg/kg) administered ip for 16 weeks suppressed body weight gain in HFD-fed rats. Weight reduction was accompanied by the reduction of visceral fat mass. Baicalin significantly decreased the elevated serum cholesterol, free fatty acid and insulin concentrations caused by the HFD. Baicalin also suppressed systemic inflammation by reducing the serum level of tumor necrosis factor alpha. Baicalin reduced hepatic lipid accumulation, enhanced the phosphorylation of AMPK and ACC and down-regulated genes involved in lipogenesis, including fatty acid synthase and its upstream regulator SREBP-1c. In HepG2 cells, baicalin (5 and 10 micromol/L) increased the phosphorylation of AMPK and decreased lipid accumulation following the addition of high glucose.


CONCLUSIONS
Our study suggests that baicalin might have beneficial effects on the development of hepatic steatosis and obesity-related disorders by targeting the hepatic AMPK.
Guo
Hong-xia
HX
State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
Liu
Dai-hua
DH
Ma
Ying
Y
Liu
Jin-feng
JF
Wang
Ying
Y
Du
Zhi-yan
ZY
Wang
Xin
X
Shen
Jing-kang
JK
Peng
Hong-li
HL
D055372:AMP-Activated Protein Kinases / Q000378:metabolism; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D004041:Dietary Fats / Q000009:adverse effects; D004305:Dose-Response Relationship, Drug; D016503:Drug Delivery Systems; D005234:Fatty Liver / Q000188:drug therapy* / Q000209:etiology; D005419:Flavonoids / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D056945:Hep G2 Cells; D006801:Humans; D008297:Male; D008659:Metabolic Diseases / Q000188:drug therapy* / Q000209:etiology; D010766:Phosphorylation / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D031364:Scutellaria baicalensis / Q000737:chemistry; D015430:Weight Gain / Q000187:drug effects
D000894:Anti-Inflammatory Agents, Non-Steroidal; D004041:Dietary Fats; D005419:Flavonoids; C038044:baicalin; D055372:AMP-Activated Protein Kinases