Arachidonic acid can significantly prevent early insulin resistance induced by a high-fat diet.
OBJECTIVE
To investigate whole-body metabolic disorder and hepatic glucose output (HGO) disturbance in rats with insulin resistance induced by a short-term high-fat diet, and the effect of arachidonic acid (AA).


METHODS
Twenty-four normal male Wistar rats (230-250 g) were randomly divided into 3 groups according to their weight and fed for 12 weeks: control group, n = 8, fed with standard chow diet; high-fat (HF) group, n = 8, fed with a high-fat diet; HF+AA group, n = 8, fed with a high-fat diet and administered orally 3 mg x kg(-1) x day(-1)AA.


RESULTS
Early insulin resistance was successfully induced in HF-fed rats with hyperinsulinemia (p < 0.05), higher plasma triglyceride (TG) (p < 0.05), higher fasting liver glycogen content (p < 0.01) and higher glucose-insulin index (p < 0.01) during an oral glucose tolerance test (OGTT). The AA treatment significantly decreased the glucose-insulin index (p < 0.01), blood TG (p < 0.05) and glycogen content (p < 0.05) in liver. Both activity of phosphoenolpyruvate carboxykinase (PEPCK) (p < 0.05) and mRNA levels of PEPCK (p < 0.05) and glucose-6-phosphatase (G-6-Pase) (p < 0.01) in liver were also observed to be significantly decreased. But there were significant differences in the glucose-insulin index (p < 0.01) during OGTT, and glycogen content (p < 0.01) between the HF+AA and control groups.


CONCLUSIONS
AA can significantly prevent whole-body insulin resistance induced by a high-fat diet, as well as accompanied HGO disturbance in the overnight fasting state, but not thoroughly.
Wu
Mianyun
M
Biochemistry Department, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Wang
Ximing
X
Duan
Qiuhong
Q
Lu
Tao
T
D000818:Animals; D016718:Arachidonic Acid / Q000494:pharmacology*; D001786:Blood Glucose / Q000378:metabolism; D004041:Dietary Fats / Q000008:administration & dosage* / Q000009:adverse effects; D005786:Gene Expression Regulation; D005951:Glucose Tolerance Test; D005952:Glucose-6-Phosphatase / Q000378:metabolism; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008099:Liver / Q000201:enzymology / Q000378:metabolism*; D008112:Liver Glycogen / Q000378:metabolism; D008297:Male; D019764:Phosphoenolpyruvate Carboxykinase (ATP) / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D014280:Triglycerides / Q000097:blood
D001786:Blood Glucose; D004041:Dietary Fats; D007328:Insulin; D008112:Liver Glycogen; D014280:Triglycerides; D016718:Arachidonic Acid; D005952:Glucose-6-Phosphatase; D019764:Phosphoenolpyruvate Carboxykinase (ATP)