title: Cutaneous injury-related structural changes and their progression following topical nitrogen mustard exposure in hairless and haired mice.
abstract: To identify effective therapies against sulfur mustard (SM)-induced skin injuries, various animals have been used to assess the cutaneous pathology and related histopathological changes of SM injuries. However, these efforts to establish relevant skin injury endpoints for efficacy studies have been limited mainly due to the restricted assess of SM. Therefore, we employed the SM analog nitrogen mustard (NM), a primary vesicating and bifunctional alkylating agent, to establish relevant endpoints for efficient efficacy studies. Our published studies show that NM (3.2 mg) exposure for 12-120 h in both the hairless SKH-1 and haired C57BL/6 mice caused clinical sequelae of toxicity similar to SM exposure in humans. The NM-induced cutaneous pathology-related structural changes were further analyzed in this study and quantified morphometrically (as percent length or area of epidermis or dermis) of skin sections in mice showing these lesions. H&E stained skin sections of both hairless and haired mice showed that NM (12-120 h) exposure caused epidermal histopathological effects such as increased epidermal thickness, epidermal-dermal separation, necrotic/dead epidermis, epidermal denuding, scab formation, parakeratosis (24-120 h), hyperkeratosis (12-120 h), and acanthosis with hyperplasia (72-120 h). Similar NM exposure in both mice caused dermal changes including necrosis, edema, increase in inflammatory cells, and red blood cell extravasation. These NM-induced cutaneous histopathological features are comparable to the reported lesions from SM exposure in humans and animal models. This study advocates the usefulness of these histopathological parameters observed due to NM exposure in screening and optimization of rescue therapies against NM and SM skin injuries.
authors.affiliation: Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora, Colorado, United States of America.
authors.forename: Neera
authors.initials: N
authors.lastname: Tewari-Singh
authors.affiliation: Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora, Colorado, United States of America.
authors.forename: Anil K
authors.initials: AK
authors.lastname: Jain
authors.affiliation: Department of Pathology, School of Medicine, University of Colorado Denver, Aurora, Colorado, United States of America.
authors.forename: David J
authors.initials: DJ
authors.lastname: Orlicky
authors.affiliation: Department of Pediatrics, School of Medicine, University of Colorado Denver, Aurora, Colorado, United States of America.
authors.forename: Carl W
authors.initials: CW
authors.lastname: White
authors.affiliation: Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Denver, Aurora, Colorado, United States of America.
authors.forename: Rajesh
authors.initials: R
authors.lastname: Agarwal
mesh_terms: D000818:Animals; D001768:Blister / Q000139:chemically induced / Q000473:pathology*; D002619:Chemical Warfare Agents / Q000633:toxicity*; D020405:Dermis / Q000187:drug effects / Q000473:pathology*; D018450:Disease Progression; D004817:Epidermis / Q000187:drug effects / Q000473:pathology*; D017488:Hyperkeratosis, Epidermolytic / Q000139:chemically induced / Q000473:pathology*; D008466:Mechlorethamine / Q000633:toxicity*; D051379:Mice; D008812:Mice, Hairless; D008810:Mice, Inbred C57BL; D009151:Mustard Gas / Q000633:toxicity; D009336:Necrosis / Q000139:chemically induced / Q000473:pathology*
chemical_list: D002619:Chemical Warfare Agents; D008466:Mechlorethamine; D009151:Mustard Gas