P021

This protocol assesses in vitro neurotoxicity by combining neuronal viability, mitochondrial/metabolic activity, neurite outgrowth, and optional neuronal network function readouts. Calcein-AM or resazurin/PrestoBlue readouts estimate viable or metabolically active cells; βIII-tubulin immunofluorescence detects neuronal morphology and neurite networks; TMRE detects mitochondrial membrane potential; and MEA recordings detect functional changes in neuronal network activity.

SH-SY5Y neuronal-like differentiation uses defined culture conditions to shift proliferative human neuroblastoma cells toward a neuron-like state, mainly assessed by reduced proliferation, neurite extension, neuronal-marker expression, and, in some protocols, increased dependence on neurotrophic support. Retinoic acid (RA) is commonly used for the first differentiation phase, and sequential RA followed by brain-derived neurotrophic factor (BDNF) in serum-free medium is a well-characterized approach for generating neuron-like SH-SY5Y cultures with extensive neurite outgrowth. The primary readouts are morphology-based neurite outgrowth and marker-based confirmation using proteins such as βIII-tubulin, MAP2, GAP43, synaptophysin, NeuN, NSE, TH, or related neuronal/synaptic markers, depending on the study endpoint.

Cell differentiation refers to the process in which cells of the same origin gradually produce cell groups with different morphological structure and functional characteristics.

Congo red amyloid staining is a histochemical method used to detect extracellular amyloid deposits in tissue sections based on the affinity of Congo red dye for β-pleated sheet-rich protein aggregates. When bound to amyloid, Congo red produces characteristic apple-green birefringence under polarized light microscopy, which is widely regarded as a diagnostic feature of amyloid deposition in histopathology. The diagnostic principle relies on the combination of dye binding (congophilia) and optical anisotropy under polarized illumination, which distinguishes amyloid from most non-amyloid eosinophilic extracellular deposits in routine histological evaluation. Amyloid identification by Congo red staining remains a cornerstone in diagnostic pathology despite the availability of adjunct methods such as immunohistochemistry and mass spectrometry, particularly because of its ability to localize deposits directly within tissue architecture. The specificity of Congo red-positive deposits is incre

Alzheimer’s Disease (AD) is a neurodegenerative disorder characterized by a progressive decline in cognitive functions and loss of specific types of neurons and synapses. Alzheimer's symptoms can be simulated in mice by injecting drugs (such as Aβ) or genetically modified.