Topical application of Acalypha indica accelerates rat cutaneous wound healing by up-regulating the expression of Type I and III collagen Moorthy Ganeshkumar a , Thangavel Ponrasu a , Rajesh Krithika b , Kuttalam Iyappan b , Vinaya Subramani Gayathri c , Lonchin Suguna a,n a Department of Biochemistry, Central Leather Research Institute—Council of Scientific and Industrial Research, Chennai 600020, India b Chemical Engineering Division, Central Leather Research Institute—Council of Scientific and Industrial Research, Chennai 600020, India c Department of Chemistry, SSN College of Engineering, Kalavakkam, Chennai 603110, India article info Article history: Received 27 December 2011 Received in revised form 14 March 2012 Accepted 6 April 2012 Available online 14 April 2012 Keywords: Acalypha indica Collagen TGF-b1 TNF-a Antioxidative abstract Ethnopharmacological relevance: Acalypha indica Linn. (Acalypha indica) vernacularly called Kuppaimeni in Tamil, has been used as a folklore medicine since ages for the treatment of wounds by tribal people of Tamil Nadu, Southern India. The present study investigates the biochemical and molecular rationale behind the healing potential of Acalypha indica on dermal wounds in rats. Material and methods: Acalypha indica extract (40 mg/kg body weight) was applied topically once a day on full-thickness excision wounds created on rats. The wound tissue was removed and used for estimation of various biochemical and biophysical analyses and to observe histopathological changes with and with-out extract treatment. The serum levels of pro-inflammatory cytokine tumor necrosis factor (TNF-a) was measured at 12 h, 24 h, 48 h and 72 h post-wounding using ELISA. Reverse transcription-polymerase chain reaction (RT-PCR) analysis was performed to study the expression pattern of transforming growth factor [TGF-b1], collagen 1 a (I) [Col 1 a (I)] and collagen 3 a (I) [Col 3 a (I)]. Likewise, linear incision wounds were created and treated with the extract and used for tensile strength measurements. Results: Wound healing in control rats was characterized by less inflammatory cell infiltration, lack of granulation tissue formation, deficit of collagen and significant decrease in biomechanical strength of wounds. Acalypha indica treatment mitigated the oxidative stress and decreased lipid peroxidation with concomitant increase in ascorbic acid levels. It also improved cellular proliferation, increased TNF-a levels during early stages of wound healing, up-regulated TGF-b1 and elevated collagen synthesis by markedly increasing the expression of Col 1 a (I) and Col 3 a (I). Increased rates of wound contraction, epithelialization, enhanced shrinkage temperature and high tensile strength were observed in the extract treated rats. Conclusion: Acalypha indica extract was shown to augment the process of dermal wound healing by its ability to increase collagen synthesis through up-regulation of key players in different phases of wound healing and by its antioxidative potential. & 2012 Elsevier Ireland Ltd. All rights reserved. 1. Introduction Wound healing is a natural process occurring in living organ- isms which results in complete or partial remodeling of injured tissue and ultimately progresses to the formation of a fibrous scar. Healing occurs in different overlapping phases and involves the interplay of several processes like inflammation, neovasculariza- tion and matrix formation (Stadelmann et al., 1998). Hubner et al. (1996) have demonstrated that impaired TNF-a expression in glucocorticoid-treated mice is associated with defects in wound healing pattern. As TNF-a precedes the expression of several growth factors, any decrease in its production may play a detrimental role on wound tissue remodeling and regeneration (Lim et al., 2006). TNF-a is also known to stimulate the produc- tion of collagen (Lawrence and Diegelmann, 1994). The multifunctional growth factor TGF-b1 has been reported to possess the broadest spectrum of action and is involved in almost all stages of wound healing. TGF-b1 facilitates the recruit- ment of inflammatory cells and augments macrophage-mediated tissue debridement, promotes angiogenesis and aids in re-epithe- lization and also increases collagen deposition in the proliferative phase (Caiado et al., 2011). It is well established now that TGF-b1 Contents lists available at SciVerse ScienceDirect journal homepage: www.elsevier.com/locate/jep Journal of Ethnopharmacology 0378-8741/$ - see front matter & 2012 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jep.2012.04.005 n Corresponding author. Tel.: þ91 44 24911386; fax: þ91 44 24911589. E-mail address: slonchin@yahoo.co.uk (L. Suguna). Journal of Ethnopharmacology 142 (2012) 14–22