Molecular and cellular pharmacology Chitosan-based copper nanocomposite accelerates healing in excision wound model in rats Anu Gopal, Vinay Kant, Anu Gopalakrishnan, Surendra K. Tandan, Dinesh Kumar n Division of Pharmacology and Toxicology, Indian Veterinary Research Institute, Izatnagar 243 122, Uttar Pradesh, India article info Article history: Received 20 August 2013 Received in revised form 19 February 2014 Accepted 28 February 2014 Available online 13 March 2014 Keywords: Copper Chitosan Wound healing VEGF TGF-β1 TNF-α abstract Copper possesses efficacy in wound healing which is a complex phenomenon involving various cells, cytokines and growth factors. Copper nanoparticles modulate cells, cytokines and growth factors involved in wound healing in a better way than copper ions. Chitosan has been shown to be beneficial in healing because of its antibacterial, antifungal, biocompatible and biodegradable polymeric nature. In the present study, chitosan-based copper nanocomposite (CCNC) was prepared by mixing chitosan and copper nanoparticles. CCNC was applied topically to evaluate its wound healing potential and to study its effects on some important components of healing process in open excision wound model in adult Wistar rats. Significant increase in wound contraction was observed in the CCNC-treated rats. The up-regulation of vascular endothelial growth factor (VEGF) and transforming growth factor-beta1(TGF-β 1 ) by CCNC- treatment revealed its role in facilitating angiogenesis, fibroblast proliferation and collagen deposition. The tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) were significantly decreased and increased, respectively, in CCNC-treated rats. Histological evaluation showed more fibroblast prolifera- tion, collagen deposition and intact re-epithelialization in CCNC-treated rats. Immunohistochemistry of CD31 revealed marked increase in angiogenesis. Thus, we concluded that chitosan-based copper nanocomposite efficiently enhanced cutaneous wound healing by modulation of various cells, cytokines and growth factors during different phases of healing process. & 2014 Elsevier B.V. All rights reserved. 1. Introduction Copper is an essential trace element for humans and animals and the ancients recognized copper as an essential healing mineral. It facilitates the activity of several enzymes (Borkow and Gabbay, 2009) and provides a role in the development and maintenance of the cardiovascular system, the skeletal system, and the structure and functions of the nervous system. It is evidenced that copper has potent antibacterial properties and is an essential element in many wound-healing-related processes (Borkow and Gabbay, 2005). The emergence of nanoscience and nanotechnology in the last decade presents opportunities for exploring the effects of copper nanoparticles in wound healing. Chitosan, a linear polysaccharide of chitin, has been proposed as a biomaterial because of its apparent satisfactory biocompat- ibility (Peluso et al., 1994). It is biocompatible and biodegradable and possesses antimicrobial, and wound healing properties which can be synergistically combined with metals like Cu 2 þ and Ag 2 þ thereby enhancing its antimicrobial and wound healing effects (Leonida et al., 2011). Various composites based on chitosan such as, silver nanocomposite have been reported with good healing activity (Chambers et al., 2007; Fredriksson et al., 2009). Wound healing involves four temporally overlapping phases i.e. hemostasis, inflammation, proliferation and remodeling (Donald and Zachary, 2011). Despite some recent advances in understanding basic principles of wound healing, it continues to cause significant morbid- ity and mortality (Fine and Mustoe, 2006). A large variety of treatment modalities are available for the wounds, including application of antibiotics, occlusive layers, bandages, poultices, mechanical devices that reduce evaporation of water and others. However, all of these modalities have one drawback in common; they all help wound healing by supporting the body mechanisms to heal the wound. Unfortunately, this passive wound healing process proves inadequate for some obstinate/recalcitrant wounds or when immunity or other body functions are compromised. To tide over such situations, a treatment modality is desired that speeds up the healing by actively regenerating the skin (dermis and epidermis). A recent study suggests that chitosan and its nanoparticles can inhibit skin aging and facilitates the extracellular matrix (ECM) in remodeling phase of wound healing (Leonida et al., 2011). The composites prepared using metal nanoparticles and polymers could find better utilization due to the enhanced antimicrobial Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/ejphar European Journal of Pharmacology http://dx.doi.org/10.1016/j.ejphar.2014.02.033 0014-2999/& 2014 Elsevier B.V. All rights reserved. n Corresponding author. Fax: þ91 581 230 3284. E-mail addresses: dineshks17@gmail.com, dineshks17@ivri.res.in (D. Kumar). European Journal of Pharmacology 731 (2014) 8–19