Silver aids healing in the sterile skin wound: experimental studies in the laboratory rat

Abstract

Incisional wounds 15 mm long were induced surgically in the back skin of young adult Wistar rats. They were sutured and used as an experimental model in the therapeutic evaluation of daily applications of 0.5 mL of silver nitrate (SN) at 0.01, 0.1 or 1.0% w/v aqueous solution, or 0.5 g silver sulphadiazine (SSD) over a 10-day period. Control wounds received deionized water only. The silver preparations were not toxic but SN did stain the hair and superficial layers of the stratum corneum. The wounds remained microbiologically clean. Wounds exposed to SN (0.1 or 1.0%) or SSD healed more rapidly than controls. From about the fourth day of treatment, we noted a more rapid exteriorization of sutures, improved wound closure and an earlier loss of scabs and wound debris. Silver treatment appeared to reduce the inflammatory and granulation tissue phases of healing and enhance epidermal repair. Silver from SN was deposited as silver sulphide in extrafollicular hair shafts and superficial aspects of the skin and wound debris but not at deeper levels. Silver uptake was four-fold higher in damaged skin than in intact tissue. SSD was absorbed by intact and wounded skin but the silver did not precipitate as silver sulphide and its localization in the tissue is not known. Uptake of silver from SN or SSD was associated with changes in the concentrations of zinc and calcium in the skin. Zinc levels were depressed during the inflammatory and proliferative phases of healing and then increased. Zinc concentrations had normalized by 10 days when wound healing was achieved. Calcium levels remained higher than normal throughout the observation period. The mechanism of action of silver in advancing wound healing in the rat is unclear. Its ability to reduce the inflammatory and granulation phases of healing, and to invoke metallothionein production and influence metal ion binding are possibly important.

Relationships Between Tensile Strength, Ascorbic Acid, Hydroxyproline, and Zinc Levels of Rabbit Full-Thickness Incision Wound Healing

“…The Zn concentrations have been reported to normalize in 10 days when rat incision back skin wound healing is achieved. 24 We observed similar results on the 15th day with normalized Zn levels and a highest tensile strength value for the rabbit back skin incision wound. Concerning these results, the healing processes increase the need for ascorbic acid and Zn in the wound tissue, especially in the first 7 days.…”

Ultrastructural localization and chemical binding of silver ions in human organotypic skin cultures

“…Despite the evident acute in vitro cytotoxicity of silver ions (Hollinger 1996;Burd et al 2007;Lansdown and Williams 2004;Brett 2006) wound healing in patients and animals treated with silver dressings is a well-known fact (Lansdown et al 1997;Jorgensen et al 2005). Thus accumulation of silver in the keratinocytes as shown in the present study does not seem to restrain the closure of the wound, undoubtly because of the presence of detoxiWcation mechanisms.…”

Topical silver sulfadiazine for the prevention of acute dermatitis during irradiation for breast cancer

“…SSD cream is a topical antibacterial used primarily as a topical burn cream which prevents the growth of a wide array of bacteria, as well as yeast, on the damaged skin [8]. According to anti-inflammatory and barrier-enhancing functions, SSD can protect the skin from entry of infectious and antigenic agents [9][10][11][12]. Evidence has shown the ameliorating effects of formulations with putative barrierenhancing activity on radiation dermatitis [21,22].…”

“…It is typically delivered in a 1% solution suspended in a water-soluble base. It also has anti-inflammatory and barrier-enhancing functions and thus can protect the skin from entry of infectious and antigenic agents [9][10][11][12]. These characteristics, in addition to providing a moist environment to the irradiated area, make SSD cream a potential preventive/therapeutic agent for acute radiation dermatitis.…”