Effects of L-carnitine on inflammatory parameters and angiogenesis in the rat air pouch model of inflammation

Abstract

Background: In this study, effects of L-carnitine on inflammatory parameters and angiogenesis were evaluated in the rat air pouch model of inflammation. Methods: Male Wistar rats were anesthetized; 20 and 10 ml sterile air was injected subcutaneously on the back of rats at first and 3rd day. To induce inflammation, carrageenan 2% was injected intrapouch at 6th day. Saline as control and L-carnitine (250, 500, 1000 and 2000 ?g/rat) were administrated intrapouch at the same time as the carrageenan injection, 24 and 48 hours after inflammation induction. After 72 hours, the pouches were opened and pouch fluids were collected to determine exudate volume, leukocyte counts, vascular endothelial growth factor (VEGF), and interleukin-1? (IL-1?) levels. The granulated tissue was dissected out and weighed. Angiogenesis in the granulation tissues was measured based on the hemoglobin concentration method. Findings: All used doses of L-carnitine reduced the leukocyte accumulation in the pouch fluid (P < 0.001); however, granulation tissue weight was decreased only by dose of 2000 ?g (P < 0.001). In addition, L-carnitine significantly reduced volume of exudate in all treatment groups. Moreover, the agent produced inhibitory effect on IL-1? level by doses of 250 and 500 ?g. L-carnitine not only did not show an inhibitory effect on VEGF concentration, but also 1000 ?g of L-carnitine increased VEGF level as compared to the control group (P < 0.010). Conclusion: Results of this study showed that the used doses of L-carnitine have anti-inflammatory effects without anti-angiogenesis activity in this model of inflammation. The anti-inflammatory effect of L-carnitine maybe related to its inhibitory effect on IL-1?. © 2017, Isfahan University of Medical Sciences(IUMS). All rights reserved.