Dextran-shelled oxygen-loaded nanodroplets reestablish a normoxia-like pro-angiogenic phenotype and behavior in hypoxic human dermal microvascular endothelium.
In chronic wounds, hypoxia seriously undermines tissue repair processes by altering the balances between pro-angiogenic proteolytic enzymes (matrix metalloproteinases, MMPs) and their inhibitors (tissue inhibitors of metalloproteinases, TIMPs) released from surrounding cells. Recently, we have shown that in human monocytes hypoxia reduces MMP-9 and increases TIMP-1 without affecting TIMP-2 secretion, whereas in human keratinocytes it reduces MMP-2, MMP-9, and TIMP-2, without affecting TIMP-1 release. Provided that the phenotype of the cellular environment is better understood, chronic wounds might be targeted by new oxygenating compounds such as chitosan- or dextran-shelled and 2H,3H-decafluoropentane-cored oxygen-loaded nanodroplets (OLNs). Here, we investigated the effects of hypoxia and dextran-shelled OLNs on the pro-angiogenic phenotype and behavior of human dermal microvascular endothelium (HMEC-1 cell line), another cell population playing key roles during wound healing. Normoxic HMEC-1 constitutively released MMP-2, TIMP-1 and TIMP-2 proteins, but not MMP-9. Hypoxia enhanced MMP-2 and reduced TIMP-1 secretion, without affecting TIMP-2 levels, and compromised cell ability to migrate and invade the extracellular matrix. When taken up by HMEC-1, nontoxic OLNs abrogated the effects of hypoxia, restoring normoxic MMP/TIMP levels and promoting cell migration, matrix invasion, and formation of microvessels. These effects were specifically dependent on time-sustained oxygen diffusion from OLN core, since they were not achieved by oxygen-free nanodroplets or oxygen-saturated solution. Collectively, these data provide new information on the effects of hypoxia on dermal endothelium and support the hypothesis that OLNs might be used as effective adjuvant tools to promote chronic wound healing processes.
Dipartimento di Scienze Biomediche, Chirurgiche e Odontoiatriche, Università di Milano, via Pascal 36, 20133 Milano, Italy. Electronic address: nicoletta.basilico@unimi.it.
Nicoletta
N
Basilico
Istituto Nazionale di Ricerca Metrologica (INRIM), Strada delle Cacce, 91, 10135 Torino, Italy. Electronic address: c.magnetto@inrim.it.
Chiara
C
Magnetto
Dipartimento di Scienze Farmacologiche e Biomolecolari, Università di Milano, via Pascal 36, 20133 Milano, Italy. Electronic address: sarah.dalessandro@unimi.it.
Sarah
S
D'Alessandro
Dipartimento di Scienze della Salute, Università di Milano Bicocca, Via Cadore 48, 20900 Monza, Italy. Electronic address: alice.panariti@mail.mcgill.ca.
Alice
A
Panariti
Dipartimento di Scienze della Salute, Università di Milano Bicocca, Via Cadore 48, 20900 Monza, Italy. Electronic address: ilaria.rivolta@unimib.it.
Ilaria
I
Rivolta
Dipartimento di Scienze della Vita e Biologia dei Sistemi, Via Accademia Albertina 13, 10123 Torino, Italy. Electronic address: tullio.genova@unito.it.
Tullio
T
Genova
Dipartimento di Neuroscienze, Università di Torino, Corso Raffaello 30, 10125 Torino, Italy. Electronic address: amina.khadjavi@unito.it.
Amina
A
Khadjavi
Dipartimento di Oncologia, Università di Torino, Via Santena 5 bis, 10126 Torino, Italy. Electronic address: giuliarossana.gulino@unito.it.
Giulia Rossana
GR
Gulino
Dipartimento di Scienza e Tecnologia del Farmaco, Università di Torino, Via Giuria, 9, 10125 Torino, Italy. Electronic address: monica.argenziano@unito.it.
Monica
M
Argenziano
Dipartimento di Scienza e Tecnologia del Farmaco, Università di Torino, Via Giuria, 9, 10125 Torino, Italy. Electronic address: marco.soster@unito.it.
Marco
M
Soster
Dipartimento di Scienza e Tecnologia del Farmaco, Università di Torino, Via Giuria, 9, 10125 Torino, Italy. Electronic address: roberta.cavalli@unito.it.
Roberta
R
Cavalli
Dipartimento di Oncologia, Università di Torino, Via Santena 5 bis, 10126 Torino, Italy. Electronic address: giuliana.giribaldi@unito.it.
Giuliana
G
Giribaldi
Dipartimento di Neuroscienze, Università di Torino, Corso Raffaello 30, 10125 Torino, Italy. Electronic address: caterina.guiot@unito.it.
Caterina
C
Guiot
Dipartimento di Neuroscienze, Università di Torino, Corso Raffaello 30, 10125 Torino, Italy. Electronic address: mauro.prato@unito.it.
Mauro
M
Prato
D043925:Angiogenesis Inducing Agents / Q000737:chemistry / Q000494:pharmacology*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D048271:Chitosan / Q000737:chemistry / Q000494:pharmacology; D003911:Dextrans / Q000737:chemistry / Q000494:pharmacology*; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005109:Extracellular Matrix / Q000187:drug effects / Q000378:metabolism; D018093:Gelatinases / Q000378:metabolism; D006801:Humans; D000860:Hypoxia / Q000188:drug therapy*; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D049329:Nanostructures / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry / Q000494:pharmacology*; D010641:Phenotype; D012867:Skin / Q000187:drug effects / Q000378:metabolism; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000378:metabolism; D014945:Wound Healing / Q000187:drug effects
D043925:Angiogenesis Inducing Agents; D003911:Dextrans; C560822:TIMP1 protein, human; C560823:TIMP2 protein, human; D019715:Tissue Inhibitor of Metalloproteinase-1; D019716:Tissue Inhibitor of Metalloproteinase-2; D048271:Chitosan; D018093:Gelatinases; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2; C579270:MMP9 protein, human; D020780:Matrix Metalloproteinase 9; D010100:Oxygen
Human microvascular endothelial cell (HMEC); Matrix metalloproteinase (MMP); Nanodroplet; Oxygen; Skin; Tissue inhibitor of metalloproteinase (TIMP)