Wound Healing Effects of a Lipocalin-Derived Peptide Luana Wlian 1 , Linda Christian Carrijo-Carvalho 1 , Sonia Aparecida Andrade 1 , Silvia Vanessa Lourenço 2 , Consuelo Junqueira Rodrigues 3 , Durvanei Augusto Maria 1 and Ana Marisa Chudzinski Tavassi 1* 1 Butantan Institute, São Paulo, Brazil 2 Dental School, University of São Paulo, São Paulo, Brazil 3 University of São Paulo, São Paulo, Brazil *Corresponding author: Ana Marisa Chudzinski Tavassi, Instituto Butantan, Laboratório de Bioquímica e Biofísica , Av. Vital Brazil, 1500, 05503-900, São Paulo, SP, Brazil, Tel: +55 11 3726 7222; E-mail: ana.chudzinski@butantan.gov.br Received date: Feb 21, 2014; Accepted date: Mar 26, 2014; Published date: Mar 31, 2014 Copyright: © 2014 Wlian L, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abstract The role of lipocalins in wound healing is currently unknown, although the involvement of these proteins in injury response has been reported. This study aimed to investigate the effects of a peptide comprising the sequence of a previously described lipocalin conserved motif (pM2b), in an experimental model of skin lesion. Circular full- thickness wounds in the skin of rat dorsum were treated with pM2b or saline as control, and allowed to heal, keeping the wound occluded and moist. During wound healing, the following parameters were evaluated in the regenerating tissue: wound closure, collagen content, glycosaminoglycans (GAGs) and metalloproteinase (MMP) activity. In addition, tissue sections were subjected to histological analysis. Treatment with pM2b promoted an overall improvement in wound healing and tissue repair, with distinctly marked signals in the early stages of wound healing, such as the presence of histiocytes, fibroblasts and thick collagen bundles, as well as early reepithelization in the recovering tissue. In the latter stages, pM2b-treated wounds showed a better resolution of wound healing, with evidence of regeneration and reduced scars. The regenerating tissue showed collagen increase, no significant changes in the total amount of GAGs, and increased MMP-2 activity, in comparison with control lesions. The results suggest that lipocalins which share the sequence motif related to pM2b can play a role in wound healing. The lipocalin-derived peptide can serve as a tool to develop new pharmaceuticals and formulations to aid wound healing. Keywords Lipocalin; Lopap; Amino acid motif; Signature sequence; Peptide; Wound healing Introduction A diversity of biological molecules is involved in triggering and regulation of wound healing and tissue repair processes. Interaction between extracellular matrix (ECM) and cells, as well as modulation of cell responses play important roles in the dynamic regulation of wound healing and establishment of normal tissue morphology and function [1-3]. Among the decisive events distinguished in wound healing are the primary hemostasis, wound contraction, cell recruitment, orchestrating of cell responses by growth factors and cytokines, and the synthesis of ECM components [4]. Collagen is the main ECM component, important to maintaining tissue integrity. During tissue repair, fibroblasts and myofibroblasts are recruited to the new forming tissue and synthesize collagen. Rapid collagen synthesis and arrangement in a well-organized pattern, equilibrated with tissue remodeling that involves the activation of matrix metalloproteinase are critical factors, which determine the success of tissue repair, and scar prevention [5,6]. Recently, lipocalins have arisen in literature as players in injury response and morphogenic processes [7-12]. Lipocalins are multifunctional proteins that can modulate cell survival, differentiation and immune responses [13-15]. We have previously demonstrated that a signature sequence is involved in the modulation of cell responses by lipocalins and have described a peptide (pM2b), which comprises the conserved sequence motif related to the lipocalin signature sequence [16,17]. In vitro assays showed this lipocalin- derived peptide triggers anti-apoptotic activity in endothelial cells and neutrophils, and is able to modulate fibroblast responses, inducing the synthesis of ECM proteins, and expression of inflammatory and cell survival mediators [16,18]. In vivo assays, pM2b also induced increased collagen synthesis in normal dermis [18]. In the present study, we evaluated the healing effects of pM2b in skin full-thickness wound. Materials and Methods Peptide and reagents The synthetic peptide (pM2b) with the amino acid sequence YAIGYSCKDYK-OH was obtained from Orpegen Pharma (Heidelberg, Germany). All other reagents were of analytical grade. Full-thickness skin lesion model Male Wistar rats aged 6-8 weeks and weighing 120-150 g were obtained from the Central Animal Breeding House, Butantan Institute. The animals were fed with standard pellet diet and water ad libitum. All procedures were approved by the institutional animal care and use committee. Rats were anesthetized with a mixture of ketamine (75 mg.kg -1 im) and xylazine (10 mg.kg -1 im). The dorsum was shaved and disinfected with ethanol. Six full-thickness round sections (three wounds on each side) of 6 mm diameter were aseptically made on the skin using a metallic punch. The wounds on the right side were topically treated with a single dose of the peptide (50 µl, 230 nM Wlian et al., J Clin Toxicol 2014, 4:2 DOI: 10.4172/2161-0495.187 Research Article Open Access J Clin Toxicol ISSN:2161-0495 JCT Volume 4 • Issue 2 • 1000187 J o u r n a l o f C li n i c a l T o x i c o l o g y ISSN: 2161-0495 Journal of Clinical Toxicology