Therapeutic Potential of Plants in Wound Healing

Introduction Wound is defined simply as the disruption of the cellular and anatomic continuity of a tissue (Bennet 1988). Wound may be produced by physical, chemical, thermal, microbial or immunological insult to the tissue. The process of wound healing consists of integrated cellular and biochemical events leading to reestablishment of structural and functional integrity with regain of strength of injured tissue. The events include coagulation, inflammation, formation of granulation tissue and tissue remodeling (Lynch 1987; Savant & Shah 1998). Clinically, one often encounters non-healing, under-healing or over healing. Therefore the aim of treating a wound is to either shorten the time required for healing or to minimize the undesired consequences (Myers et al 1980). Attention is directed towards discovering an agent, which will accelerate wound healing either when it is progressing normally (Brown et al., 1988a; Mather et al., 1989), or when it is suppressed by various agents like corticosteroids (Ehrlich & Hunt 1968), antineoplastics (Raju & Kulkarni 1986), non steroidal anti-inflammatory agents (Lee 1968 b). Medical treatment of wound includes administration of drugs either locally (topical) or systemically (oral or parenteral) in an attempt to aid wound repair (Savanth & Shah 1998; Rains & Mann 1988; Moy 1993). The topical agents used include antibiotics and antiseptics (Chulani 1996), desloughing agents (chemical debridement, e.g. Hydrogen peroxide, eusol and collagenase ointment) (Savanth & Mehta 1998), wound healing promoters (eg. Tretinoin, aloe vera extract, honey, comfrey, benzoyl peroxide, chamomilia extract, dexpanthenol, tetrachlordecaxide solution, clostebol acetate and the experimental cytokines. Various growth factors like platelet derived growth factor, macrophage derived growth factor, monocyte derived growth factor (Brown et al., 1988a; Mather et al., 1989) etc. are necessary for the initiation and promotion of wound healing. Many substances like tissue extracts (Udupa et al 1991; Ramesh et al., 1990), vitamins (Williams & Bissel 1944), minerals (Rao et al., 1988a) and a number of plant products (Dahanukar et al., 2000; Sharma et al., 1990; Udupa et al., 1991); have been reported by various workers, to possess prohealing effects. These approaches are being advocated in wound management as body’s repair kit (McAuliffe 1989). Consequently there exists a need for new agents which may be useful in proper wound management. In this direction a number of herbal products are being investigated.