SFRP2 Is Associated with Increased Adiposity and VEGF Expression.

Area of Science:

• Endocrinology and Metabolism
• Adipose Tissue Biology
• Molecular Biology

Background:

• Secreted frizzled-related protein 2 (sFRP2) is implicated in various biological processes.
• The role of sFRP2 in adipose tissue and its contribution to metabolic health remain incompletely understood.

Purpose of the Study:

• To investigate depot-specific expression and secretion of sFRP2 by adipose tissue.
• To determine the effects of sFRP2 on adipocyte biology, including lipogenesis, proliferation, and angiogenesis.
• To explore the relationship between serum sFRP2 levels and metabolic parameters in humans.

Main Methods:

• Assessed sFRP2 mRNA and protein expression in mouse and human adipose tissues using PCR and Western blot.
• Measured sFRP2 secretion from adipose tissue in vitro.
• Evaluated the impact of recombinant sFRP2 on adipocyte lipogenesis, proliferation, and angiogenic gene expression (VEGF, NFATC3).
• Correlated serum sFRP2 levels with body mass index (BMI), glycaemia, and insulin resistance in 106 patients.

Main Results:

• sFRP2 mRNA was expressed in both mouse and human adipose tissue, with significantly higher expression in omental compared to subcutaneous adipose tissue.
• Omental adipose tissue secreted 63% more sFRP2 protein than subcutaneous adipose tissue.
• Recombinant sFRP2 did not affect lipogenesis or preadipocyte proliferation but increased VEGF mRNA expression.
• Serum sFRP2 levels positively correlated with BMI and circulating insulin levels.
• Patients with abnormal glucose tolerance exhibited higher serum sFRP2 levels than controls.

Conclusions:

• Circulating sFRP2 is associated with adipose tissue mass.
• sFRP2 may promote adipose tissue angiogenesis by enhancing VEGF expression.
• These findings suggest a potential role for sFRP2 in regulating adipose tissue function and metabolic health.