A high carbohydrate diet induces insulin resistance through decreased glucose utilization in ovariectomized rats.
BACKGROUND
Recent research has reported that high sugar diets increase insulin resistance, without abdominal obesity, in male, but not female Wistar rats. Whether a high sucrose (SU) diet increased insulin resistance in ovariectomized (OVX) rats was determined.


METHODS
Female Sprague Dawley rats, weighing 273 +/- 20 g, had either an ovariectomy or a sham operation (sham). OVX and sham rats were divided into two groups: one group had a 68 En% SU diet and the other a 68 En% starch (ST) diet for 8 weeks.


RESULTS
The body weight was higher in the OVX than the sham rats, regardless of dietary carbohydrate subtype. The fasting serum glucose levels did not differ according to diet and ovariectomy. However, the fasting serum insulin levels were higher in the OVX than the sham rats, and in the OVX rats, a high SU diet increased the serum insulin levels more than a high ST diet. The whole body glucose disposal rates, which referred to the state of insulin sensitivity, were lower in the OVX rats fed both the high SU and ST diets, compared to sham rats. Glycogen deposits in the soleus and quadriceps muscles were lower in the OVX rats fed high SU and ST diets than in sham rats. The glucose transporter 4 content and fraction velocity of glycogen synthase in muscles showed similar glucose disposal rates. However, the triacylglycerol content in the muscles were higher in the OVX rats with a high SU diet than those with a high ST diet.


CONCLUSIONS
These results suggested that an OVX increased the weight gain due to higher food intakes, regardless of dietary carbohydrate subtypes. OVX-induced obesity may be involved in the induction of insulin resistance from an increased triacylglycerol content, decreased glucose uptake and glycogen synthesis in skeletal muscles, regardless of dietary carbohydrate subtypes.
Park
Sun Min
SM
Department of Food & Nutrition, College of Natural Science, Hoseo University, Asan, Korea.
Park
Chun Hee
CH
Wha
Jun Dong
JD
Choi
Soo Bong
SB
D000818:Animals; D001786:Blood Glucose / Q000187:drug effects* / Q000378:metabolism*; D001835:Body Weight / Q000187:drug effects; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D002149:Energy Intake / Q000187:drug effects; D004958:Estradiol / Q000097:blood; D005260:Female; D015309:Glucose Clamp Technique; D051275:Glucose Transporter Type 4 / Q000187:drug effects / Q000378:metabolism; D006003:Glycogen / Q000378:metabolism; D006006:Glycogen Synthase / Q000187:drug effects / Q000378:metabolism; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D020738:Leptin / Q000097:blood; D023421:Models, Animal; D018482:Muscle, Skeletal / Q000378:metabolism; D010052:Ovariectomy; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D014280:Triglycerides / Q000378:metabolism
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D051275:Glucose Transporter Type 4; D007328:Insulin; D020738:Leptin; C495694:Slc2a4 protein, rat; D014280:Triglycerides; D004958:Estradiol; D006003:Glycogen; D006006:Glycogen Synthase