Diplacone

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.

ROS/oxidative-stress fluorescent staining uses cell-permeant fluorogenic probes that become fluorescent after oxidation inside cells or tissues; commonly used examples include DCFH-DA/DCFDA for broad cellular oxidant detection, DHE for superoxide-related signal detection, MitoSOX for mitochondrial superoxide-related signal detection, and CellROX probes for oxidative-stress-associated fluorescence readouts. The assay detects probe oxidation rather than a single ROS species unless the probe and analysis method have been chemically validated for that species. DCFH-DA enters cells, is deacetylated by intracellular esterases to DCFH, and produces fluorescent DCF after oxidation, so the readout is used as an operational measure of total cellular oxidative stress rather than a species-specific ROS measurement. DHE and MitoSOX can report superoxide-related oxidation, but red fluorescence alone can include non-specific ethidium-like oxidation products; HPLC or optimized spectral approaches are

Dextran sulfate sodium (DSS)-induced colitis is generated by administering DSS in mouse drinking water, producing epithelial injury, barrier disruption, weight loss, diarrhea, fecal blood, colon shortening, histologic mucosal damage, and inflammatory mediator changes; the model is mainly used to study acute or chronic intestinal inflammation resembling selected features of ulcerative colitis. DSS injury is interpreted through clinical and tissue readouts rather than a single molecular endpoint: daily body weight, stool consistency, and bleeding are combined into a disease activity index, while colon length, histology, cytokines, myeloperoxidase activity, intestinal permeability, and tight-junction markers provide complementary measures of inflammation and barrier damage.

TNBS-induced colitis is produced by intrarectal delivery of 2,4,6-trinitrobenzene sulfonic acid in ethanol, where ethanol disrupts the mucosal barrier and TNBS haptenates colonic proteins, generating immune-mediated colonic inflammation with weight loss, diarrhea, ulceration, transmural injury, inflammatory-cell infiltration, and cytokine responses. The model is used as an experimental intestinal inflammation model with Crohn’s disease–like features, especially when Th1-type responses, IL-12–dependent inflammation, chronic relapsing inflammation, or fibrosis-related endpoints are studied.

Apoptosis is a regulated, generally non-lytic cell-death pathway that removes unwanted, damaged, infected, or abnormal cells through coordinated morphological changes, caspase activation, DNA fragmentation, and membrane remodeling. The intrinsic apoptosis pathway is controlled mainly by mitochondrial outer membrane permeabilization, BCL-2 family proteins, cytochrome c release, apoptosome formation, caspase-9 activation, and downstream executioner caspase-3/7 activation. The extrinsic apoptosis pathway is initiated by death receptors such as Fas, TNFR, and TRAIL receptors, which recruit adaptor proteins and activate caspase-8 before engaging executioner caspases or mitochondrial amplification through BID cleavage. Apoptosis is linked to many phenotypes, including cancer cell killing, tissue homeostasis, immune regulation, neurodegeneration, infection response, and treatment-induced cytotoxicity; unresolved questions include how apoptosis interacts with necroptosis, pyroptosis, ferroptos

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

Ca²⁺ staining is an experimental technique that utilizes specific fluorescent probes (such as Fluo-4 AM, Fura-2, etc.) to qualitatively or quantitatively detect dynamic changes in intracellular Ca²⁺ concentrations; this is achieved by monitoring the changes in fluorescent signals generated when these probes bind to free intracellular calcium ions. The underlying principle relies primarily on the presence of chelating groups within the probe's molecular structure that possess high affinity for calcium ions.

The NLRP3 inflammasome is a cytosolic innate immune signaling platform that integrates priming signals and danger-signal activation to promote caspase-1 activation, maturation of IL-1β and IL-18, and gasdermin D-mediated pyroptotic cell death. The core experimental logic is to determine whether inflammatory disease phenotypes are driven by increased NLRP3 expression, ASC-containing inflammasome assembly, caspase-1 cleavage, GSDMD cleavage, and extracellular release of IL-1β/IL-18 rather than by nonspecific cell injury alone. The pathway is strongly linked to inflammation-related disease phenotypes because monosodium urate crystals activate NALP3/NLRP3 inflammasome signaling in gout-like crystal inflammation, cholesterol crystals activate NLRP3 inflammasomes in atherogenesis models, and DSS-induced intestinal inflammation has been reported to involve NLRP3 inflammasome activity. However, experimental colitis studies also show context-dependent protective effects of NLRP3 inflammasome co