INTERNATIONAL JOURNAL OFREVIEW ARTICLEPHARMACEUTICAL INNOVATIONS ISSN 2249-1031number of drugs are developed fromplants that are active against a number ofdiseases including wound healing [3] .<strong>Wound</strong>s are physical injuries that result inan opening or breaking of the skin. <strong>Wound</strong>is defined as the disruption of the cellular<strong>and</strong> anatomic continuity of a living tissue.<strong>Wound</strong> may be produced by physical,chemical, thermal, microbial orimmunological insult to the tissues [4] .Types of wounds:<strong>Wound</strong>s are classified into differentcategories on the basis of underlying causeof wound creation <strong>and</strong> on the basis ofphysiology of wound healing as shownbelow-TYPES OF WOUNDSBased onunderlying causeofwound creationBased onPhysiology ofwound healingOpen woundsClosed woundsAcute woundsChronic wounds*Abrasion wounds*Lacration wounds*Incised wounds*Puncure wounds*Penetrationwounds*Gunshot wounds*Contusion*Hematomas* Crush injuriesVolume 3, Issue 4, July − August 201331 | P a g ehttp://www.ijpi.org
INTERNATIONAL JOURNAL OFREVIEW ARTICLEPHARMACEUTICAL INNOVATIONS ISSN 2249-1031Mechanism of <strong>Wound</strong> <strong>Healing</strong><strong>Wound</strong> healing is a complex process <strong>and</strong>consists of integrated cellular <strong>and</strong>biochemical events that lead to reestablishmentof structural <strong>and</strong> functionalintegrity <strong>with</strong> regain of strength in injuredtissues. Proper healing of wounds isessential for the restoration of disruptedanatomical continuity <strong>and</strong> disturbedfunctional status of the skin.The response to injury is immediate <strong>and</strong>the damaged tissue or wound for properhealing passes through three broadphases [5, 6] . These are‣ The inflammatory phase‣ The fibroplastic phase‣ The remodelling phaseThe inflammatory phase prepares thearea for healing <strong>and</strong> immobilizes thewound by causing it to swell <strong>and</strong> becomepainful, so that movement becomesrestricted. The fibroplastic phase rebuildsthe structure <strong>and</strong> then the remodellingphase provides the final healed form.<strong>Wound</strong>s affect physical <strong>and</strong> mentalhealth of millions of patients <strong>and</strong> imposesignificant cost to them. [7] . Impairedwound healing can result into severemorbidity leading to long hospitalizationof patients. There are many factors thatcan interfere <strong>with</strong> wound healing process<strong>and</strong> thus causing improper or impairedwound healing. These factors includepoor nutrition, insufficient oxygenation,infection, prolonged inflammation, age,diabetes <strong>and</strong> other diseases, drugs,smoking, alcoholism, depression,oxidative stress <strong>and</strong> many more [8] .Volume 3, Issue 4, July − August 2013Oxidative stress plays an important rolein impaired wound healing <strong>and</strong> causesdamage to the growing tissue at therepair site. Oxidative stress results froman imbalance between the generation ofreactive oxygen species <strong>and</strong> endogenousantioxidant systems. In the inflammatoryphase of wound healing, reactive oxygenspecies are produced as a defencemechanism against invading bacteria byneutrophills <strong>and</strong> macrophages, <strong>and</strong> lowlevels of ROS are also essentialmediators of intracellular signalling .<strong>Wound</strong> related non-phagocytic cells alsogenerate free radicals by involving nonphagocyticNADPH oxidase mechanism[9] . However, excessive amounts of ROSare deleterious due to their high reactivity<strong>and</strong> causes oxidative stress. The processof wound healing may be hampered bythe presence of these free radicals whichcan damage the cells surrounding thewound in excessive amount. At highconcentration ROSs also induce severtissue damage, pathogenesis of chronic,non-healing wound <strong>and</strong> even lead toneoplastic transformation which furtherdelay healing process by causing damageto cellular membranes, DNA , proteins<strong>and</strong> lipids[10] . Therefore, a tightregulation of ROS production <strong>and</strong>detoxification is crucial for the normalrepair process.<strong>Antioxidant</strong>s reduce these effects causedby oxidative stress by reacting <strong>with</strong> thesefree radicals or ROSs <strong>and</strong> act as freeradical scavengers. Free-radicalscavengingenzymes are cytoprotectiveenzymes that have an essential role in thereduction, deactivation <strong>and</strong> removal of32 | P a g ehttp://www.ijpi.org