KHK-2898

Cytotoxicity assays are usually based on the assessment of cell membrane damage, which can also be indirectly detected by measuring cell viability. Detection methods include MTT assay, CKK-8 assay, LDH assay and ATP assay, etc.

Live/dead viability and cytotoxicity staining assays are based on the simultaneous detection of intracellular esterase activity in metabolically active (viable) cells and membrane integrity loss in non-viable cells. In commonly used dual-staining approaches, membrane-permeant fluorogenic substrates are converted by intracellular esterases into fluorescent products in live cells, while impermeant DNA-binding dyes selectively enter cells with compromised plasma membranes and label nucleic acids in dead or dying cells, enabling discrimination between viable and non-viable populations by fluorescence microscopy or flow cytometry.

Ferroptosis is an iron-dependent, non-apoptotic form of regulated cell death characterized by lethal lipid peroxidation and sensitivity to suppression by iron chelators or lipophilic radical-trapping antioxidants. The core pathway links cystine uptake through system Xc−, glutathione availability, GPX4-dependent detoxification of phospholipid hydroperoxides, iron-dependent oxidative reactions, and polyunsaturated-phospholipid metabolism into a cell-death program that is biochemically and morphologically distinct from apoptosis, necrosis, and autophagy. The ferroptosis pathway is experimentally linked to phenotype through chemical and genetic perturbation. Erastin induces ferroptosis by inhibiting cystine uptake through system Xc− and weakening antioxidant defenses, while GPX4 inhibition or depletion causes lipid peroxide accumulation and ferroptotic cancer-cell death. ACSL4 and oxidizable arachidonoyl- or adrenoyl-containing phosphatidylethanolamines shape ferroptosis sensitivity by con

The following protocol uses the MTT colorimetric assay as a classic literature-established method for assessing cell viability/metabolic activity in cultured mammalian cells. MTT[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] is reduced by metabolically active cells to a colored formazan product; the amount of formazan is quantified spectrophotometrically and provides an indirect measure of metabolically active viable cells. Importantly, MTT reduction reflects cellular oxidoreductase/metabolic activity rather than an absolute direct count of living cells, so changes in cellular metabolism can alter the signal independently of cell number.