Anti-inflammatory agent 56

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

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

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

PINK1/Parkin-mediated mitophagy pathway is a mitochondrial quality-control signaling axis in which mitochondrial depolarization stabilizes PINK1 on damaged mitochondria, activates Parkin recruitment and E3 ubiquitin ligase activity, promotes ubiquitination of outer mitochondrial membrane proteins, recruits selective autophagy adaptors, and drives lysosomal degradation of damaged mitochondria. In neurological disease research, this pathway is experimentally important because neurons, especially dopaminergic neurons, are highly dependent on mitochondrial integrity, and defective mitochondrial turnover can lead to mitochondrial dysfunction, oxidative stress, impaired neuronal survival, α-synuclein accumulation, and neuroinflammatory damage-associated signals. The genetic disease link is strongest in Parkinson’s disease because mutations in PRKN/parkin cause autosomal recessive juvenile parkinsonism, mutations in PINK1 cause hereditary early-onset Parkinson’s disease, and Drosophila studie

Acute systemic toxicity studies evaluate adverse effects occurring after a single exposure, or repeated exposure within a short acute window, and the main in vivo readouts are mortality, moribund condition, clinical signs, body-weight change, and gross pathological findings; acute oral toxicity methods were developed to replace classical LD50 testing with reduced-animal designs such as fixed-dose procedure, acute toxic class method, and up-and-down procedure. The fixed-dose procedure classifies acute toxicity by administering predefined dose levels and observing evident toxicity rather than using death as the primary endpoint, whereas the acute toxic class method uses sequential groups of three animals per step and the up-and-down procedure doses animals sequentially to estimate an LD50 with fewer animals than conventional LD50 testing.