Tissue repair and wound healing are complex processes involving clotting, fibrin-fibronectin deposition, inflammation, re-epithelialization, neovascularization, fibroplasia, and wound contraction. Interactions of different cell types, extracellular matrix proteins and their receptors are involved in these biological significant processes, which are mediated by cytokines and growth factors. In the normal host, wound healing is usually uncomplicated and proceeds at a rapid rate. In contrast, most healing failures are associated with some form of host impairment, including diabetes, infection, immunosuppression, obesity, or malnutrition. Wound healing studies that focus on models of impaired healing, therefore, have greater clinical relevance. Diabetes probably represents the prototype of impaired healing models since multiple factors contribute towards the impairment, including peripheral vascular disease, sensory and autonomic neuropathy, and lowered immunity against infections. Recently, we have shown that treatment with a novel pharmacological agent picroliv, resulted in enhanced proliferation and migration of endothelial cells in an ex-vivo model of angiogenesis. Picroliv treatment also increased expression of growth factors that regulate the angiogenic process. The objective of this proposal is to understand effectiveness and underlying mechanism of angiogenic agent picroliv for the better management of chronic and diabetic wounds. To accomplish this objective, we plan to study the effect of picroliv on the growth of human vein endothelial cells. Cell viability and cytotoxicity studies will include cell morphology and lactate dehydrogenase (LDH) activity. We will examine whether picroliv enhances angiogenesis in an in-vitro and in vivo model of angiogenesis. We will use genetically diabetic mice models of impaired healing for our study. Additionally, it is well known that the anti-inflammatory and immunosuppressive activities of corticosteroids suppress healing. We will therefore use animal models wherein healing has been impaired by treatment with steroids. Several wound healing parameters such as wound width and gap, vessel formation, collagenization, apoptosis will be studied in tissues obtained from these models. The regulation of growth factors viz. TGFb-1, bFGF, PDGF, IGF-1 and adhesion molecules will be examined in the wound tissue by immunohistochemistry, RT-PCR as well as by in situ hybridization. Further, to understand the molecular mechanism of action of picroliv, we will examine the profile of metalloprotienases such as MMPl, MMP9, MMP2, and their tissue inhibitors (TIMPs) in the wound tissue by gelatinography and PCR. We believe that these studies will provide information regarding the mechanism(s) underlying the angiogenic effects of picroliv in better management of chronic wounds.
| Singh, Anoop K; Sharma, Anuj; Warren, James et al. (2007) Picroliv accelerates epithelialization and angiogenesis in rat wounds. Planta Med 73:251-6 |
| Sharma, Anuj; Singh, Anoop K; Warren, James et al. (2006) Differential regulation of angiogenic genes in diabetic wound healing. J Invest Dermatol 126:2323-31 |
| Maheshwari, Radha K; Singh, Anoop K; Gaddipati, Jaya et al. (2006) Multiple biological activities of curcumin: a short review. Life Sci 78:2081-7 |
