Senolytic Therapies For Neurodegenerative Diseases is a treatment approach for neurodegenerative diseases. This page provides comprehensive information about its mechanism of action, clinical evidence, and therapeutic potential.
Senolytic drugs selectively eliminate senescent cells that accumulate with age and secrete pro-inflammatory "senescence-associated secretory phenotype" (SASP) factors[1]. These senescent cells contribute to chronic neuroinflammation and neuronal dysfunction in neurodegenerative diseases, making senolytics a promising therapeutic approach[2].
Cellular senescence is a state of irreversible cell cycle arrest characterized by the secretion of pro-inflammatory cytokines, chemokines, growth factors, and proteases collectively known as the SASP. In the brain, senescent neurons, astrocytes, and microglia accumulate with age and in neurodegenerative diseases, creating a toxic microenvironment that promotes disease progression.
Senescent cells in the brain exhibit distinct characteristics[3]:
| Marker | Detection | Significance |
|---|---|---|
| p16^INK4a | IHC, qPCR | Cell cycle arrest |
| p21^CIP1 | IHC, Western | Cell cycle arrest |
| SA-β-gal | Histochemistry | Senescence marker |
| SASP factors | ELISA, multiplex | Inflammation |
The SASP includes:
A critical feature of senescent cells is their ability to induce senescence in neighboring cells through:
This creates a spread of senescence throughout tissues, amplifying the toxic microenvironment.
| Target | Function | Senolytic Drug | Mechanism |
|---|---|---|---|
| Bcl-2 family | Anti-apoptotic | Dasatinib + Quercetin | Inhibits survival signaling |
| p53 | Apoptosis regulator | Nutlin-3a | MDM2 activator |
| PI3K/Akt | Survival pathway | Navitoclax (ABT-263) | Bcl-2 inhibitor |
| HSP90 | Chaperone function | Geldanamycin | Inhibits protein folding |
| γ-secretase | Notch signaling | DAPT | Protease inhibition |
The most extensively studied senolytic combination:
| Property | Dasatinib | Quercetin |
|---|---|---|
| Class | Tyrosine kinase inhibitor | Flavonoid |
| Primary target | Bcr-Abl, Src | Multiple kinases |
| Senolytic target | Bcl-2, Src | PI3K, Bcl-2 |
| FDA status | Approved (leukemia) | Dietary supplement |
Clinical Trials:
Dosing: Dasatinib 100mg + Quercetin 1000mg, intermittent dosing
An alternative combination being explored:
A natural flavonoid with senolytic activity:
Bcl-2 family inhibitor:
| Drug | Class | Status |
|---|---|---|
| ABT-737 | Bcl-2 inhibitor | Preclinical |
| 17-DMAG | HSP90 inhibitor | Preclinical |
| Rapamycin | mTOR inhibitor | Clinical |
| Metformin | AMPK activator | Clinical |
| Trial | Drug | Phase | Status | Outcome |
|---|---|---|---|---|
| NCT03415087 | D+Q | I | Completed | Safety, biomarkers |
| NCT0341504 | Fisetin | II | Recruiting | Cognitive endpoints |
| NCT04063124 | D+Q | I | Ongoing | Safety, SASP markers |
Biomarker Findings:
| Trial | Drug | Phase | Status |
|---|---|---|---|
| NCT04685590 | D+Q | I/II | Ongoing |
| NCT04446303 | Fisetin | I | Planning |
Preclinical Evidence:
| Drug | Common AEs | Serious AEs |
|---|---|---|
| Dasatinib | Fluid retention, rash | Pleural effusion |
| Quercetin | Generally well-tolerated | GI upset at high doses |
| Navitoclax | Thrombocytopenia | Cytopenias |
| Fisetin | Well-tolerated | Limited data |
The study of Senolytic Therapies For Neurodegenerative Diseases has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
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He S, Sharpless NE. Senescence in health and disease. Cell. 2017;169(6):1000-1011. PMID:28575665
Kirkland JL, Tchkonia T. Clinical strategies for targeting senolytic drugs. Aging Cell. 2020;19(2):e13108.
Xu M, Pirtskhalava T, Farr JN, et al. Senolytics improve physical function and increase lifespan in old age. Nat Med. 2018;24(8):1246-1256.
Bussian TJ, Aziz A, Meyer CF, et al. Clearance of senescent glial cells prevents tau-dependent pathology. Nature. 2018;563(7732):578-582.
Musi N, Valentine JM, Sickora KR, et al. Tau protein aggregation is associated with cellular senescence in the brain. Aging Cell. 2018;17(6):e12840.
Ogrodnik M, Zhu Y, Langhi LGP, et al. Obesity-induced cellular senescence drives anxiety and impairs neurogenesis. Cell Metab. 2019;29(5):1061-1077.e8.
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Walaszczyk A, Dookun E, Redgrave R, et al. Senolytic drugs relieve pain in a mouse model of osteoarthritis. Aging Cell. 2023;22(1):e13754.
Zhang P, Kishimoto Y, Grammatikakis I, et al. Senolytic therapy improves myelin regeneration in aged mice. Nat Aging. 2023;3(2):176-191.