Inflammatory Signaling in Neurodegenerative Diseases

Inflammatory signalling has emerged as a central feature in the onset and progression of neurodegenerative disorders such as Alzheimer’s disease, Parkinson’s disease and diverse tauopathies. Initially viewed as a secondary response to neuronal injury, chronic activation of the innate immune system in the brain is now recognised as a driver of neuronal dysfunction and synaptic loss. Resident glial cells, in particular microglia and astrocytes, respond to pathogenic proteins and environmental insults by releasing pro-inflammatory mediators and reactive oxygen species. These soluble factors can amplify local inflammation, promote protein misfolding and compromise neuronal survival. Key intracellular pathways, notably those governed by nuclear factor-κB (NF-κB) and Toll-like receptor cascades, modulate the balance between protective clearance of aggregates and deleterious chronic inflammation. Recent advances have elucidated cell-type specificity in these signalling networks and unveiled novel regulators that link systemic risk factors—such as vascular disease and air pollution—to central nervous system inflammation. This evolving understanding has spurred the development of therapeutic strategies aimed at selectively modulating inflammatory pathways to restore neuronal homeostasis and delay disease progression.

Research from Nature Portfolio

Recent studies have demonstrated that microglial NF-κB signalling directly contributes to the propagation and toxicity of pathogenic tau assemblies in models of tauopathy. Constitutive activation of microglial NF-κB exacerbates tau seeding, spreading and associated synaptic deficits, whereas genetic or pharmacological inhibition of NF-κB in these cells reduces tau release and rescues autophagy function. In aged animals, suppression of microglial NF-κB not only ameliorates learning and memory deficits but also remodels disease-associated microglial states, shifting them towards a homeostatic profile despite elevated neuronal tau inclusions. These findings establish microglial NF-κB as a pivotal mediator of neurodegenerative spread and underscore the potential of cell-type specific immune modulation as a therapeutic avenue.

Inflammatory Signaling in Neurodegenerative Diseases publication trend

The graph below shows the total number of articles in inflammatory signaling in neurodegenerative diseases across all publications each year (not limited to Nature Index journals).

Technical terms

Neuroinflammation: Activation of the brain’s innate immune response, often involving glial cells, leading to the release of inflammatory mediators.

Microglia: Resident immune cells of the central nervous system responsible for sensing pathological stimuli and orchestrating inflammatory responses.

Astrocytes: Star-shaped glial cells that support neuronal function and contribute to inflammatory signalling when activated.

NF-κB signalling pathway: A transcriptional cascade controlling expression of pro-inflammatory genes and cell-survival factors.

TLR4/MYD88 pathway: A receptor-adaptor cascade that recognises pathogen-associated or damage-associated signals and activates innate immunity.

Cytokine: Soluble protein released by immune cells that mediates intercellular communication during inflammatory responses.

Tauopathy: A class of neurodegenerative disorders characterised by accumulation of abnormally phosphorylated tau protein.

Amyloid-β: Peptide fragments that aggregate to form extracellular plaques, a hallmark of Alzheimer’s disease pathology.

References

1. Neurodegenerative effects of air pollutant Particles: Biological mechanisms implicated for Early-Onset Alzheimer’s disease. Environment International (2024).
2. Catalpol rescues cognitive deficits by attenuating amyloid β plaques and neuroinflammation. Biomedicine & Pharmacotherapy (2023).
3. Meta‐analysis and transcriptomic analysis reveal that NKRF and ZBTB17 regulate the NF‐κB signaling pathway, contributing to the shared molecular mechanisms of Alzheimer's disease and atherosclerosis. CNS Neuroscience & Therapeutics (2024).
4. Microglial NF-κB drives tau spreading and toxicity in a mouse model of tauopathy. Nature Communications (2022).