Compounds used for 'Injection Lipolysis' destroy adipocytes and other cells found in adipose tissue

Background: A widely applied technique to reduce subcutaneous fat pad size involves subcutaneous injection of a phosphatidylcholine preparation ('injection lipolysis'). As the mode of action is mostly unknown, we planned to study cellular effects of the particular drug used in Germany (Lipostabil). Methods: Human preadipocytes, adipocytes, vascular and skeletal muscle cells as well as renal epithelial cells were incubated in the compound, morphological changes were described, and cell vitality was measured. Results: A strong cytolytic effect of the compound was signified by lipid release and acridine orange staining of dying adipocyte nuclei. When the undiluted compound was used, more than 90% of cell death occurred after 90 s in preadipocytes, after 6 min in vascular smooth muscle cells, skeletal myotubes and renal epithelial cells, and after 15 min in adipocytes. Dilution slowed down cytolysis, but still >50% of the cells disappeared during 30 min incubation. Neither osmotic effects nor differences in medium acidity were responsible for cell death. Conclusion: Injection lipolysis with phosphatidylcholine as the major injected compound reduces subcutaneous fat pad size through cell and tissue destruction. Beside the lack of a clear risk-benefit analysis, applying this technique represents off-label drug use and application of a drug by a contraindicated route