Biocompatibility and characterization of polyglycerol-based thermoresponsive nanogels designed as novel drug-delivery systems and their intracellular localization in keratinocytes.
Novel nanogels that possess the capacity to change their physico-chemical properties in response to external stimuli are promising drug-delivery candidates for the treatment of severe skin diseases. As thermoresponsive nanogels (tNGs) are capable of enhancing penetration through biological barriers such as the stratum corneum and are taken up by keratinocytes of human skin, potential adverse consequences of their exposure must be elucidated. In this study, tNGs were synthesized from dendritic polyglycerol (dPG) and two thermoresponsive polymers. tNG_dPG_tPG are the combination of dPG with poly(glycidyl methyl ether-co-ethyl glycidyl ether) (p(GME-co-EGE)) and tNG_dPG_pNIPAM the one with poly(N-isopropylacrylamide) (pNIPAM). Both thermoresponsive nanogels are able to incorporate high amounts of dexamethasone and tacrolimus, drugs used in the treatment of severe skin diseases. Cellular uptake, intracellular localization and the toxicological properties of the tNGs were comprehensively characterized in primary normal human keratinocytes (NHK) and in spontaneously transformed aneuploid immortal keratinocyte cell line from adult human skin (HaCaT). Laser scanning confocal microscopy revealed fluorescently labeled tNGs entered into the cells and localized predominantly within lysosomal compartments. MTT assay, comet assay and carboxy-H2DCFDA assay, demonstrated neither cytotoxic or genotoxic effects, nor any induction of reactive oxygen species of the tNGs in keratinocytes. In addition, both tNGs were devoid of eye irritation potential as shown by bovine corneal opacity and permeability (BCOP) test and red blood cell (RBC) hemolysis assay. Therefore, our study provides evidence that tNGs are locally well tolerated and underlines their potential for cutaneous drug delivery.
a Institute of Nutritional Science, Department of Nutritional Toxicology , University of Potsdam , Arthur-Scheunert-Allee 114-116 , Nuthetal , Germany.
Christian
C
Gerecke
a Institute of Nutritional Science, Department of Nutritional Toxicology , University of Potsdam , Arthur-Scheunert-Allee 114-116 , Nuthetal , Germany.
Alexander
A
Edlich
b Institute of Chemistry and Biochemistry , Freie Universität Berlin , Berlin , Germany.
Michael
M
Giulbudagian
a Institute of Nutritional Science, Department of Nutritional Toxicology , University of Potsdam , Arthur-Scheunert-Allee 114-116 , Nuthetal , Germany.|c Department of Molecular Biology , University of Duisburg-Essen , Essen , Germany.
Fabian
F
Schumacher
d Institute for Pharmacy (Pharmacology and Toxicology) , Freie Universität Berlin , Berlin , Germany.
Nan
N
Zhang
d Institute for Pharmacy (Pharmacology and Toxicology) , Freie Universität Berlin , Berlin , Germany.
Andre
A
Said
d Institute for Pharmacy (Pharmacology and Toxicology) , Freie Universität Berlin , Berlin , Germany.
Guy
G
Yealland
e Charité - Universitätsmedizin Berlin, Department of Dermatology, Venerology and Allergology , Center of Experimental and Applied Cutaneous Physiology , Berlin , Germany.
Silke B
SB
Lohan
b Institute of Chemistry and Biochemistry , Freie Universität Berlin , Berlin , Germany.
Falko
F
Neumann
e Charité - Universitätsmedizin Berlin, Department of Dermatology, Venerology and Allergology , Center of Experimental and Applied Cutaneous Physiology , Berlin , Germany.
Martina C
MC
Meinke
f Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht , Teltow , Germany.
Nan
N
Ma
b Institute of Chemistry and Biochemistry , Freie Universität Berlin , Berlin , Germany.
Marcelo
M
Calderón
d Institute for Pharmacy (Pharmacology and Toxicology) , Freie Universität Berlin , Berlin , Germany.
Sarah
S
Hedtrich
d Institute for Pharmacy (Pharmacology and Toxicology) , Freie Universität Berlin , Berlin , Germany.
Monika
M
Schäfer-Korting
a Institute of Nutritional Science, Department of Nutritional Toxicology , University of Potsdam , Arthur-Scheunert-Allee 114-116 , Nuthetal , Germany.
Burkhard
B
Kleuser
D000180:Acrylic Resins; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D002417:Cattle; D002470:Cell Survival / Q000187:drug effects; D020552:Comet Assay; D003315:Cornea / Q000187:drug effects; D004249:DNA Damage; D004337:Drug Carriers / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D004912:Erythrocytes / Q000187:drug effects; D005990:Glycerol / Q000737:chemistry*; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism*; D018613:Microscopy, Confocal; D000080385:Nanogels; D011092:Polyethylene Glycols / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D011094:Polyethyleneimine / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity; D011108:Polymers / Q000737:chemistry*; D061251:Primary Cell Culture; D012867:Skin / Q000378:metabolism*; D012869:Skin Absorption; D013696:Temperature
D000180:Acrylic Resins; D001672:Biocompatible Materials; D004337:Drug Carriers; D000080385:Nanogels; D011108:Polymers; C413692:polyethylene glycol polyethyleneimine nanogel; C052970:poly-N-isopropylacrylamide; C043941:polyglycerol; D011092:Polyethylene Glycols; D011094:Polyethyleneimine; D005990:Glycerol
Drug delivery; keratinocytes; nanoparticles; nanotoxicology; particle characterization