4-aminopyridine attenuates inflammation and apoptosis and increases angiogenesis to promote skin regeneration following a burn injury in mice.


Journal

Cell death discovery
ISSN: 2058-7716
Titre abrégé: Cell Death Discov
Pays: United States
ID NLM: 101665035

Informations de publication

Date de publication:
04 Oct 2024
Historique:
received: 03 07 2024
accepted: 27 09 2024
revised: 23 09 2024
medline: 5 10 2024
pubmed: 5 10 2024
entrez: 4 10 2024
Statut: epublish

Résumé

Severe thermal skin burns are complicated by inflammation and apoptosis, which delays wound healing and contributes to significant morbidity. Diverse treatments demonstrate limited success in mitigating these processes to accelerate healing. Agents that alter cell behavior to improve healing would alter treatment paradigms. We repurposed 4-aminopyridine (4-AP), a drug approved by the US FDA for multiple sclerosis, to treat severe burns in mice (10-week-old C57BL/6 J male mice weighing 25 ± 3 g). We found that 4-AP, in the early stages of burn healing, significantly reduced the expression of pro-inflammatory cytokines IL1β and TNFα while increasing the expression of anti-inflammatory markers CD206, ARG-1, and IL10. We demonstrated increased intracellular calcium effects of 4-AP through Orai1-pSTAT6 signaling, where 4-AP significantly mitigated inflammatory effects by promoting M2 macrophage differentiation in in-vitro macrophages and post-skin burn tissues. 4-AP attenuated apoptosis, with decreases in apoptotic markers BAX, caspase-9, and caspase-3 and increases in anti-apoptotic markers BCL2 and BCL-XL. Furthermore, 4-AP promoted angiogenesis through increases in the expression of CD31, VEGF, and eNOS. Together, these likely contributed to accelerated burn wound closure, as demonstrated in increased keratinocyte proliferation (K14) and differentiation (K10) markers. In the later stages of burn healing, 4-AP increased TGFβ and FGF levels, which are known to mark the transformation of fibroblasts to myofibroblasts. This was further demonstrated by an increased expression of α-SMA and vimentin, as well as higher levels of collagen I and III, MMP 3, and 9 in mice treated with 4-AP. Our findings support the idea that 4-AP may have a novel, clinically relevant therapeutic use in promoting burn wound healing.

Identifiants

pubmed: 39366954
doi: 10.1038/s41420-024-02199-6
pii: 10.1038/s41420-024-02199-6
doi:

Types de publication

Journal Article

Langues

eng

Pagination

428

Subventions

Organisme : U.S. Department of Health & Human Services | National Institutes of Health (NIH)
ID : K08 AR060164-01A
Organisme : U.S. Department of Defense (United States Department of Defense)
ID : W81XWH-16-1-0725

Informations de copyright

© 2024. The Author(s).

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Auteurs

Rahul V G (R)

Department of Orthopaedics and Sports Medicine, University of Arizona College of Medicine, Tucson, AZ, 85724, USA.

Govindaraj Ellur (G)

Department of Orthopaedics and Sports Medicine, University of Arizona College of Medicine, Tucson, AZ, 85724, USA.

Amir A Gaber (A)

Department of Orthopaedics and Sports Medicine, University of Arizona College of Medicine, Tucson, AZ, 85724, USA.

Prem Kumar Govindappa (PK)

Department of Orthopaedics and Sports Medicine, University of Arizona College of Medicine, Tucson, AZ, 85724, USA. pkgovindappa@gmail.com.

John C Elfar (JC)

Department of Orthopaedics and Sports Medicine, University of Arizona College of Medicine, Tucson, AZ, 85724, USA. openelfar@gmail.com.

Classifications MeSH