The effects of cucurbitacin E on two lymphocyte models

Abstract

Cucurbitacin E (CuE), like other cucurbitacins, is a potential anti-neoplastic agent. The aim of the present study was to investigate the in vitro effects of CuE on phytohaemagglutinin (PHA)-activated and unstimulated lymphocytes. CuE did not produce any significant cytotoxic effects on the two models. On the contrary, it had a stimulatory effect, and was capable of inducing and maintaining high proliferation rates in lymphocytes. The stimulatory effect of CuE was concentration-dependent with a median stimulatory concentration (SC50) of 1.166 µM and reaching maximal effect at a concentration of 10–20 µM. The stimulatory effect of CuE was about 25% lower than that of PHA, but a combination of CuE and PHA had an additive effect producing a greater response than that induced by the two substances used separately. Agarose gel electrophoresis for DNA fragmentation failed to show any significant apoptotic activity in the cells after 48 h exposure to CuE.