Nutr Res Pract.  2012 Aug;6(4):322-327.

Sorghum extract exerts an anti-diabetic effect by improving insulin sensitivity via PPAR-gamma in mice fed a high-fat diet

• Park JH
• Lee SH
• Chung IM
• Park Y

Abstract

This study investigated the hypothesis that a sorghum extract exerts anti-diabetic effects through a mechanism that improves insulin sensitivity via peroxisome proliferator-activated receptor gamma (PPAR-gamma) from adipose tissue. Seven C57BL/6 mice were fed an AIN-93M diet with fat consisting of 10% of total energy intake (LF) for 14 weeks, and 21 mice were fed a high-fat AIN diet with 60% of calories derived from fat (HF). From week 8, the HF diet-fed mice were orally administered either saline (HF group), 0.5% (0.5% SE group), or 1% sorghum extract (1% SE group) for 6 weeks (n = 7/group). Perirenal fat content was significantly lower in the 0.5% SE and 1% SE groups than that in the HF mice. Levels of total and low-density lipoprotein cholesterol, triglycerides, glucose, and the area under the curve for glucose were significantly lower in mice administered 0.5% SE and 1% SE than those in HF mice. Serum insulin level was significantly lower in mice administered 1% SE than that in HF mice or those given 0.5% SE. PPAR-gamma expression was significantly higher, whereas the expression of tumor necrosis factor-alpha was significantly lower in mice given 1% SE compared to those in the HF mice. Adiponectin expression was also significantly higher in mice given 0.5% SE and 1% SE than that in the HF mice. These results suggest that the hypoglycemic effect of SE may be related with the regulation of PPAR-gamma-mediated metabolism in this mouse model.

Keyword

Glucose metabolism; mice; PPAR-gamma; TNF-alpha; sorghum extract

MeSH Terms

Adiponectin
Adipose Tissue
Animals
Cholesterol
Diet
Diet, High-Fat
Energy Intake
Glucose
Hypoglycemic Agents
Insulin
Insulin Resistance
Lipoproteins
Mice
PPAR gamma
Sorghum
Triglycerides
Tumor Necrosis Factor-alpha
Adiponectin
Cholesterol
Glucose
Hypoglycemic Agents
Insulin
Lipoproteins
PPAR gamma
Triglycerides
Tumor Necrosis Factor-alpha

Figure

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  Fig. 1 Effect of sorghum extract on the oral glucose tolerance test. Values are expressed as mean ± standard error; n = 7/group. LF, low fat diet; HF, high fat diet; 0.5% SE, high fat diet with 0.5% of dietary intake as sorghum extract, 1% SE, high fat diet with 1% of dietary intake as sorghum extract. Values with different letters are significantly different at P < 0.05 by analysis of variance followed by Duncan's multiple-range test.

• 

  Fig. 2 Effect of sorghum extracts on peroxisome proliferator-activated receptor gamma (PPAR-γ), tumor necrosis factor-α (TNF-α), and adiponectin protein expression in adipose tissue. Values are expressed as means ± standard error; n = 7/group. LF, low fat diet; HF, high fat diet; 0.5% SE, high fat diet with 0.5% of dietary intake as sorghum extract; 1% SE, high fat diet with 1% of dietary intake as sorghum extract. Values with different letters are significantly different at P < 0.05 by analysis of variance followed by Duncan's multiple-range test.

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