Adipose-derived stem cells sustain prolonged angiogenesis through leptin secretion.

Area of Science:

• Stem Cell Biology
• Angiogenesis Research
• Tissue Engineering

Background:

• Adipose-derived stem cells (ASCs) are known to influence tissue remodeling via secreted factors.
• Understanding the specific roles of ASCs under different conditions is crucial for therapeutic applications.

Purpose of the Study:

• To compare the cytokine profiles of normoxic ASCs (nASCs) and hypoxia-conditioned ASCs (hASCs).
• To investigate the impact of ASC-conditioned media on endothelial cell function, particularly angiogenesis.
• To elucidate the role of leptin in hypoxia-induced ASC-mediated angiogenic effects.

Main Methods:

• ASCs were cultured under normoxic and hypoxic conditions.
• Secreted cytokine profiles were analyzed, focusing on leptin and VEGF.
• Conditioned media (CM) from hASCs and nASCs were applied to endothelial cells (ECs).
• EC tube formation assays were performed.
• The effects of exogenous leptin on ECs, including receptor expression (HIFs, Flt-1, Tie-1), were assessed.

Main Results:

• Hypoxia induced transient VEGF upregulation and significant, sustained leptin mRNA upregulation in ASCs (up to 60-fold by day 7).
• CM from hASCs markedly enhanced EC tube formation compared to CM from nASCs.
• Exogenous leptin stimulated HIF2-α expression and upregulated proangiogenic receptors Flt-1 and Tie-1 in ECs.

Conclusions:

• Hypoxia-conditioned ASCs exhibit enhanced angiogenic potential.
• Leptin is identified as a key secreted factor mediating the proangiogenic effects of hASCs.
• hASCs, through leptin release, may be particularly effective in promoting angiogenesis for therapeutic purposes.