P-536

By lysing cells, releasing RNA, and removing impurities such as proteins and DNA, high-purity RNA products are finally obtained. The commonly used traditional method is the guanidine isothiocyanate/phenol/chloroform method (Trizol), which is suitable for a variety of animal materials including animal tissues, microorganisms, cultured cells, etc., and most plant materials.

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

Endocrine diseases often arise from disrupted hormone production, hormone signaling, or target-tissue responsiveness; for diabetes-focused endocrine disease models, insulin signaling regulates glucose uptake, hepatic glucose output, lipid metabolism, and β-cell compensation. Type 2 diabetes develops through interacting defects in insulin resistance, β-cell dysfunction, adipose inflammation, hepatic glucose overproduction, altered incretin signaling, and ectopic lipid metabolism. A major unresolved question is whether endocrine dysfunction is driven primarily by target-tissue insulin resistance, intrinsic β-cell failure, immune/inflammatory stress, or combined multi-organ failure that differs by disease stage.

Cardiovascular disease can be modeled as maladaptive cardiac remodeling, where ischemic injury or pressure overload activates inflammatory signaling, fibroblast activation, extracellular-matrix deposition, cardiomyocyte hypertrophy, vascular remodeling, and progressive ventricular dysfunction. The TGF-β/SMAD axis is a central profibrotic pathway after myocardial injury and pressure overload, while innate immune and cytokine pathways regulate leukocyte recruitment, scar formation, and adverse remodeling. Key unresolved questions include which inflammatory signals are reparative versus harmful, when fibrosis is protective versus maladaptive, and whether pathway inhibition improves function without weakening necessary infarct healing or compensatory remodeling.

AMP-activated protein kinase, AMPK, is a conserved cellular energy sensor that responds to reduced cellular energy status and coordinates metabolism by increasing ATP-generating catabolic pathways while suppressing ATP-consuming anabolic processes. In metabolic disease research, the AMPK pathway is experimentally relevant because it regulates hepatic lipid synthesis, fatty acid oxidation, glucose production, skeletal-muscle glucose disposal, mTORC1-linked biosynthesis, autophagy, mitochondrial homeostasis, and whole-body energy balance. The central pathway logic is that energy stress, metformin, exercise-like stimulation, or direct AMPK activators increase AMPKα Thr172 phosphorylation and downstream substrate phosphorylation, including ACC and RAPTOR. Phosphorylation of ACC suppresses lipogenesis and supports fatty acid oxidation, whereas phosphorylation of RAPTOR suppresses mTORC1 signaling and links cellular energy status to growth and protein synthesis control. The pathway is linked