Effect of Caralluma Fimbriata Extract on 3T3-L1 Pre-Adipocyte Cell Division

A standardized extract of the plant Caralluma fimbriata (Slimaluma?) is widely used in the management of obesity but its mode of action is not yet clarified. This study investigated the ability of Caralluma fimbriata extract (CFE) to modify pre-adipocyte cell division and thus the development of hyper-plastic obesity. Mouse 3T3-L1 pre-adipocyte cell line samples were treated with different concentrations of an extract of CFE standardized against its pregnane glycoside content. Plain medium formed the negative control and hydroxyurea was the positive control. The cells were counted at 12-hour intervals, and their viability tested using the MTT assay. The treated cells were subjected to direct and indirect immunofluorescent assays for cyclin D1. CFE inhibited 3T3-L1 cell growth in a dose and duration-dependent manner, with results comparable to those produced by hydroxyurea. The viability of CFE-treated cells was reduced. Direct and indirect immunofluorescent assays demonstrated that CFE inhibits import of cyclin D1into the nucleus. CFE appears to inhibit pre-adipocyte cell division by interfering with a mechanism preceding the import of cyclin D1-CDk4/6 complex into the nucleus during the early G1 phase of the cell cycle, suggesting that CFE has the potential to inhibit hyperplastic obesity.