Wallerian degeneration: an emerging axon death pathway linking injury and disease

Laura Conforti1, Jonathan Gilley2, Michael P Coleman3

  • 11] School of Biomedical Sciences, University of Nottingham, Medical School, Queen's Medical Centre, Nottingham, NG7 2UH, UK. [2].

Related Concept Videos

Neurogenesis and Regeneration of Nervous Tissue01:15

Neurogenesis and Regeneration of Nervous Tissue

In the CNS, neurogenesis, the birth of new neurons from stem cells, is limited to the hippocampus in adults. In other regions of the brain and spinal cord, neurogenesis is almost non-existent due to inhibitory influences from neuroglia, especially oligodendrocytes, and the absence of growth-stimulating cues. The myelin produced by oligodendrocytes in the CNS inhibits neuronal regeneration. Furthermore, astrocytes proliferate rapidly after neuronal damage, forming scar tissue that physically...
2.1K
Secondary Spinal Cord Injury llI: Pathophysiology01:25

Secondary Spinal Cord Injury llI: Pathophysiology

Early Ischemia and Ionic ImbalanceWithin minutes of spinal cord injury, a secondary cascade begins, progressing over hours to weeks. Vascular damage reduces blood flow, causing ischemia and mitochondrial dysfunction. ATP depletion leads to ion pump failure, membrane depolarization, sodium influx, potassium efflux, and water accumulation, resulting in cellular swelling. Increased intracellular calcium further disrupts mitochondria and accelerates cellular injury.Excitotoxicity and Neuronal...
51
Spinal Cord Injury ll: Pathophysiology01:14

Spinal Cord Injury ll: Pathophysiology

Spinal cord injury progresses through two interconnected phases: primary injury and secondary injury.Primary InjuryPrimary injury happens at the moment of trauma and involves immediate mechanical damage to the spinal cord.Compression happens when broken vertebrae, herniated discs, or accumulating blood (such as a hematoma) press directly against the spinal cord, distorting its normal shape and function. In cases of contusion, the cord is bruised by a blunt force (like penetrating injuries or...
23
Alzheimer Disease ll: Pathophysiology01:23

Alzheimer Disease ll: Pathophysiology

Alzheimer disease involves structural changes in the brain that begin long before symptoms appear. The most distinctive features are extracellular neuritic plaques and intracellular neurofibrillary tangles.Neuritic plaques form in the cerebral cortex and around blood vessels. These plaques contain a dense core of beta-amyloid (Aβ)—a toxic protein fragment that clumps outside neurons. The core is surrounded by damaged neuronal extensions, as well as reactive astrocytes and...
34
Canonical Wnt Signaling Pathway02:54

Canonical Wnt Signaling Pathway

The gene encoding the main signaling molecules of the Wnt signaling pathways (the Wnt proteins) was discovered almost four decades ago by Nüsslein-Volhard and Wieschaus. They identified and originally named the gene "wingless" (wg) after a phenotype discovered during their landmark genetic screen in Drosophila for body pattern defects. At around the same time, another researcher named Harold Varmus found that a murine tumor virus activates the mammalian wg homolog, Int-1, which...
8.6K
Cellular Injury IlI: Cellular Death01:11

Cellular Injury IlI: Cellular Death

Cell death is the irreversible loss of cellular structure and function, representing the final stage of severe injury. It plays a key role in both normal physiology and disease.Types of Cell DeathThe two main types are necrosis and apoptosis, though others like necroptosis and pyroptosis also exist.Necrosis:Necrosis is an unregulated form of cell death caused by severe injury such as trauma, toxins, or ischemia. It is characterized by cell swelling, membrane loss, rupture, and leakage of...
68