Lipedema is characterized by localized accumulation of fat in the extremities, which is typically unresponsive to dietary regimes or physical activity. Although the disease is well described and has a high incidence, little is known regarding the molecular and cellular mechanisms underlying its pathogenesis. The aim of this study was to investigate the pathophysiology of lipedema adipose cells in vitro.
Adipose stem cells (ADSCs) were isolated from lipoaspirates derived from lipedema and non-lipedema patients undergoing tumescent liposuction. In vitro differentiation studies were performed for up to 14 days using adipogenic or regular culture medium. Supernatants and cell lysates were tested for adiponectin, leptin, insulin-like growth factor-1 (IGF-1), aromatase (CYP19A1), and interleukin-8 (IL-8) contents at days 7 and 14, using enzyme-linked immunosorbent assays (ELISAs). Adipogenesis was evaluated by visualizing and measuring cytoplasmic lipid accumulation.
Lipedema ADSCs showed impeded adipogenesis already at early stages of in vitro differentiation. Concomitantly with a strongly reduced cytoplasmic lipid accumulation, significantly lower amounts of adiponectin and leptin were detectable in supernatants from lipedema ADSCs and adipocytes compared to control cells. Additionally, lipedema and non-lipedema cells differed in their expression of IGF-1, aromatase (CYP19A1), IL-8 and in their proliferative activity.
Our findings indicate that in vitro adipogenesis of lipedema ADSCs is severely hampered in comparison to non-lipedema ADSCs. Lipedema adipose cells not only differ in their lipid storage capacity but also in their adipokine expression pattern. This might serve as a valuable marker for diagnosis of lipedema, probably from an early stage on.
1 Department of Plastic Surgery and Hand Surgery, Klinikum rechts der Isar, Technical University Munich, Germany
2 Praxis Ästhetik in München, Dr. von Lukowicz, Munich, Germany
3 Department of Plastic, Reconstructive and Aesthetic Surgery, Ospedale Regionale di Lugano, Ente Ospedaliero Cantonale, Lugano, Switzerland
4 Department of Biosciences, University of Salzburg, Austria
5 Institute of Tendon and Bone Regeneration, Paracelsus Medical University Salzburg, Austria
Financial Disclosure Statement: Nothing to disclose
Corresponding author: Anna-Theresa Bauer, MD, Klinik und Poliklinik für Plastische Chirurgie und Handchirurgie, Klinikum rechts der Isar, Technische Universität München, Ismaningerstrasse 22, D-81675 München, Germany. Phone: +49 (0) 89 4140-2171 Fax: +49 (0) 89 4140-4869, Email: email@example.com