Obesity Is Associated with Distorted Proteoglycan Expression in Adipose Tissue

Area of Science:

• Biochemistry
• Molecular Biology
• Adipose Tissue Biology

Background:

• Proteoglycans are key extracellular matrix (ECM) components involved in inflammation.
• Obesity is characterized by altered ECM morphology and increased inflammation in white adipose tissue.
• The effects of obesity and weight loss on adipose tissue proteoglycan expression remain largely unknown.

Purpose of the Study:

• To investigate the relationship between adiposity and proteoglycan expression in adipose tissue.
• To analyze changes in proteoglycan and ECM-related gene expression following weight loss in humans and in a mouse model of obesity.

Main Methods:

• Analysis of transcriptomic data from human bariatric surgery cohorts.
• Quantitative real-time PCR (RT-qPCR) on adipose tissues from male and female mice on a high-fat diet.
• Examination of both visceral and subcutaneous adipose tissue depots.

Main Results:

• Adipose mRNA expression of proteoglycans, their biosynthetic enzymes, and ECM proteins were altered in human cohorts post-surgery.
• Significant alterations in ECM gene expression, including VCAN, OGN, GPC4, and COL1A1, were observed in visceral adipose tissue after surgery.
• Gene expression analyses in mice revealed sex-specific differences in adipose tissue compartments in obesity.

Conclusions:

• Adipose tissue gene expression related to proteoglycans and ECM is significantly impacted by obesity and subsequent weight loss.
• Visceral adipose tissue shows more profound gene expression changes post-surgery, indicating potential challenges in tissue remodeling.
• These findings highlight the role of proteoglycans in adipose tissue during obesity and suggest ongoing repair processes post-weight loss.