TSH stimulates adipogenesis in mouse embryonic stem cells

Area of Science:

• Endocrinology
• Stem Cell Biology
• Adipose Tissue Biology

Background:

• Thyroid-stimulating hormone (TSH) is primarily known for regulating thyroid function and growth.
• TSH receptor (TSHR) expression has been identified in preadipocytes and adipocytes, suggesting a potential role in adipose tissue.
• The precise function of TSH in adipogenesis remains largely undefined.

Purpose of the Study:

• To investigate the role of TSH in adipose differentiation using an in vitro model.
• To determine if TSHR expression and signaling are involved in adipogenesis.
• To ascertain whether TSH acts as a pro-adipogenic factor.

Main Methods:

• Utilized a 3-week in vitro model of adipogenesis from mouse embryonic stem (ES) cells.
• Monitored TSHR expression and intracellular cAMP levels in response to TSH.
• Assessed the impact of TSH on adipogenesis with and without standard adipogenic factors.

Main Results:

• TSHR expression was upregulated during the terminal differentiation of adipocytes derived from ES cells.
• TSH stimulation led to increased intracellular cAMP production in differentiated adipocytes, indicating TSHR activation.
• TSH significantly enhanced adipogenesis when added with adipogenic factors and also stimulated adipogenesis independently of these factors.

Conclusions:

• TSH acts as a pro-adipogenic factor, promoting the conversion of ES cells into adipocytes.
• TSH signaling through TSHR plays a direct role in regulating adipogenesis.
• ES cells provide a valuable in vitro model for studying TSH's influence on adipose tissue physiology.