Induction of fat cell necrosis in human fat tissue after treatment with phosphatidylcholine and deoxycholate

Abstract

Injections with phosphatidylcholine- and deoxycholate-containing substances are used to treat localized fat accumulation and lipomas. It is believed that the injected substances induce fat cell destruction with subsequent acute panniculitis followed by a repair process of the treated fat tissue. We investigated whether necrosis or apoptosis of fat cells was induced by the injected substances. Samples of fat tissue of lipoma were collected at various times after injection and evaluated by light and electron microscopy, by immunostaining for active caspase-3 and antideoxyribonuclease I, in situ end-labelling (TUNEL staining), and biochemical caspase-3 assays. Light and electron microscopy showed fat cell necrosis in all areas of the treated lipomas. Low levels of active caspase-3 indicated the absence of apoptosis. Injection of the lipolytic substances phosphatidylcholine and deoxycholate leads to fat cell necrosis rather than apoptosis. However, additional studies evaluating different dosing and further time points after treatment are necessary.