Substance P Drives Abnormal Lymphatic Vessel Growth in Dry Eye Disease
The substance P/NK1R system promotes pathologic corneal lymphangiogenesis in dry eye disease by upregulating VEGFR3 on lymphatic cells — identifying NK1R antagonists as potential treatments for dry eye-related lymphatic vessel invasion.
Quick Facts
What This Study Found
SP/NK1R system promotes corneal lymphangiogenesis in DED by upregulating VEGFR3 expression on HDLECs. DED mouse model confirmed NK1R-dependent lymphatic vessel invasion. NK1R antagonism could inhibit pathologic lymphangiogenesis.
Key Numbers
NK1R antagonist suppressed VEGF-C, VEGF-D, VEGFR3; improved fluorescein staining and tear production in DED mice
How They Did This
In vitro + animal study. Human dermal lymphatic endothelial cells (HDLECs): immunocytochemistry, angiogenesis assay, Western blot for SP/NK1R effects on VEGFR3. DED induced in wild-type C57BL/6 mice. Corneal lymphangiogenesis assessment.
Why This Research Matters
Dry eye affects hundreds of millions worldwide. Current treatments manage symptoms but don't address the underlying lymphatic vessel invasion that perpetuates inflammation. Blocking SP/NK1R could break this cycle.
The Bigger Picture
Substance P's role in dry eye extends beyond pain — it drives the structural vascular changes that make the disease chronic. This connects neuropeptide biology to the ophthalmology field's search for disease-modifying dry eye treatments.
What This Study Doesn't Tell Us
Mouse DED model may not replicate all aspects of human dry eye. Human cell data is in vitro. NK1R antagonist treatment not tested in the DED model. Clinical translation needs confirmation.
Questions This Raises
- ?Would NK1R antagonist eye drops prevent lymphatic invasion in dry eye patients?
- ?Does blocking SP/NK1R reduce dry eye inflammation or just lymphatic growth?
- ?Could this pathway explain why some dry eye patients progress while others stabilize?
Trust & Context
- Key Stat:
- NK1R drives lymphatic invasion Substance P promotes abnormal lymphatic vessel growth in the cornea that perpetuates dry eye inflammation — a new mechanism explaining chronic disease and a druggable target
- Evidence Grade:
- Moderate evidence: combined human cell and animal model data with clear mechanistic pathway. Treatment efficacy not yet tested.
- Study Age:
- Published 2021. NK1R as a target for ocular surface disease continues to be explored.
- Original Title:
- Corneal lymphangiogenesis in dry eye disease is regulated by substance P/neurokinin-1 receptor system through controlling expression of vascular endothelial growth factor receptor 3.
- Published In:
- The ocular surface, 22, 72-79 (2021)
- Authors:
- Lee, Seok Jae, Im, Sang-Taek(2), Wu, Jun, Cho, Chang Sik, Jo, Dong Hyun, Chen, Yihe, Dana, Reza, Kim, Jeong Hun, Lee, Sang-Mok
- Database ID:
- RPEP-05537
Evidence Hierarchy
Frequently Asked Questions
Why do new blood/lymphatic vessels grow in dry eye?
Chronic inflammation from dry eye triggers substance P release, which activates NK1R receptors on lymphatic cells and increases VEGFR3 expression. This drives abnormal lymphatic vessel growth into the normally vessel-free cornea, creating a cycle of worsening inflammation.
Could blocking substance P treat dry eye?
This study suggests yes — blocking the substance P/NK1R system could prevent the abnormal lymphatic vessel growth that perpetuates dry eye inflammation. NK1R blocking drugs already exist and could potentially be formulated as eye drops.
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Cite This Study
https://rethinkpeptides.com/research/RPEP-05537APA
Lee, Seok Jae; Im, Sang-Taek; Wu, Jun; Cho, Chang Sik; Jo, Dong Hyun; Chen, Yihe; Dana, Reza; Kim, Jeong Hun; Lee, Sang-Mok. (2021). Corneal lymphangiogenesis in dry eye disease is regulated by substance P/neurokinin-1 receptor system through controlling expression of vascular endothelial growth factor receptor 3.. The ocular surface, 22, 72-79. https://doi.org/10.1016/j.jtos.2021.07.003
MLA
Lee, Seok Jae, et al. "Corneal lymphangiogenesis in dry eye disease is regulated by substance P/neurokinin-1 receptor system through controlling expression of vascular endothelial growth factor receptor 3.." The ocular surface, 2021. https://doi.org/10.1016/j.jtos.2021.07.003
RethinkPeptides
RethinkPeptides Research Database. "Corneal lymphangiogenesis in dry eye disease is regulated by..." RPEP-05537. Retrieved from https://rethinkpeptides.com/research/lee-2021-corneal-lymphangiogenesis-in-dry
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.