[Depot-specific expression of caveolin-1 in human adipose tissue and their relationship with obesity and insulin resistance].

Abstract

OBJECTIVE:

To explore the depot-specific mRNA and protein expression of caveolin-1 (CAV-1) in human subcutaneous and omental adipose tissues and analyze their relationship with obesity and insulin resistance.

METHODS:

A total of 41 subjects with normal glucose regulation were recruited. Among them, there were 29 cases with normal body mass index (BMI) and 12 cases with BMI ≥ 24 kg/m(2). All were scheduled to undergone selective abdominal operations. The levels of fasting insulin (FINS) were measured by chemiluminescence enzyme-linked immunosorbent assay (ELISA) kit. Fasting plasma glucose (FPG) was tested by glucose oxidase and home model insulin resistance index (HOMA-IR) calculated. Real-time polymerase chain reaction (RT-PCR) and Western blotting were employed to assess the relative mRNA and protein expression of caveolin-1 in subcutaneous and omental adipose tissues. And the mRNA and protein expression of caveolin-1 from different fat depots were compared and their correlations with BMI and HOMA-IR analyzed.

RESULTS:

(1) FINS and HOMA-IR were significantly higher in the overweight and obesity group than those in the normal BMI group (FINS: (8.82 ± 3.79) mU/L vs (6.43 ± 4.38) mU/L, P < 0.05, HOMA-1R: 1.91 ± 0.85 vs 1.36 ± 0.72, P < 0.05). (2) The normal BMI group patients had the higher expression levels of caveolin-1 mRNA in omental adipose tissue than overweight counterparts (2.84 ± 0.86 vs 1.02 ± 0.36, P < 0.01). But the difference in subcutaneous adipose tissue was not significant (P > 0.05). (3) The caveolin-1 protein expression in omental adipose tissue of the normal BMI group was higher than that of overweight patients (1.68 ± 0.67 vs 0.73 ± 0.29, P < 0.05). And the difference between two groups was not significant (P > 0.05). (4)The expressions of caveolin-1 mRNA in omental adipose tissue were negatively correlated with BMI, waist circumstance, triglyceride and HOMA-IR (r = -0.441, -0.615, -0.539, -0.688, P < 0.05). No correlations were found between the expressions of caveolin-1 mRNA in subcutaneous adipose tissue with BMI, waist circumstance and HOMA-IR (P > 0.05).

CONCLUSION:

Differential depot-specific expressions of caveolin-1 are present in human subcutaneous and omental adipose tissues. A low expression of caveolin-1 in omental adipose tissue may contribute to the pathogenesis of obesity and insulin resistance.

• Authors: Xiao-feng Li, Hong-yun Lu, Wei Jiang, Ya-wei Qiu, Long-yi Zeng
• Journal: Zhonghua yi xue za zhi (Zhonghua Yi Xue Za Zhi) Vol. 92 Issue 20 Pg. 1388-91 (May 29 2012) ISSN: 0376-2491 [Print] China
• PMID: 22883195 (Publication Type: English Abstract, Journal Article, Research Support, U.S. Gov't, Non-P.H.S.)

Chemical References

• CAV1 protein, human
• Caveolin 1

Topics

• Adipose Tissue (metabolism)
• Adolescent
• Adult
• Body Mass Index
• Case-Control Studies
• Caveolin 1 (metabolism)
• Female
• Humans
• Insulin Resistance
• Middle Aged
• Obesity (metabolism)
• Overweight (metabolism)
• Subcutaneous Fat (metabolism)
• Young Adult