Diethylmaleate

DEM induces upregulation of GSH(L-c-glutamyl-L-cysteinyl-glycine) metabolism, and the downregulation of pathways of cancer, chemokine signaling, cytokine-cytokine receptor, and focal adhesion in transformed cells. DEM appears to modify microenvironment of transformed cells thereby restraining tumor cell growth. DEM is cytotoxic to the transformed cells in a concentration dependent manner. DEM at 0.25 mM decreases cell viability to 75%. The co-exposure of cells to DEM+GSHe inhibits DEM induced cytotoxicity. DEM exposure increases the ROS generation by multiple orders of magnitude in transformed cells. This is evident from the dose and time dependent increase in fluorescence intensity of CMH2DCFDA. Moreover, DEM activates MAPK pathway and DEM induced activation of ERK is found to be due to phosphorylation at Thr 202/204^[1].

A stock solution of DEM is prepared in 100% DMSO and diluted in DMEM to achieve the desired concentration with less than 0.1% DMSO in the culture wells. Briefly, cells are seeded (1 ×10⁴ cells/well) in 96-well plates and allowed to adhere overnight. Subsequently, these cells are exposed to DEM at various test concentrations (0.05-1 mM) or co-exposed to equimolar (0.25 mM) DEM+GSHe for 24 h. Cell viability is determined by recording the OD at 570 nm in an Elisa microplate reader.

Sperm motility and epididymal sperm count are significantly reduced in the DEM treated animals. Fertility status is also affected by DEM exposure as is evident from the percent fertility and the litter size. consequences of the oxidative stress produced by the DEM induces glutathione depletion, on the reproductive ability of male mice and modulation of the various components of the antioxidant defense system at the transcriptional level^[4].