Abstract 14771: Iron Plays a Role in the Thrombus Formation of a Rat Model of Deep Vein Thrombosis

Abstract

Introduction: Deep vein thrombosis (DVT) is a major cause of pulmonary thromboembolism. On the other hand, iron is an essential element for maintaining physiological homeostasis in the body, whereas excess iron leads to toxicity and free radical damage. Hence, iron accumulation is associated with the pathogenesis of several cardiovascular diseases. We have previously reported that dietary iron restriction (IR) prevents the development of hypertension and chronic kidney disease (CKD) in animal models of several cardiovascular diseases. In addition, we have shown that intracellular iron transport protein, transferrin receptor 1 (TfR1), is involved in the mechanism of several cardiovascular diseases. In this study, we hypothesized that iron and TfR1 play roles in the pathogenesis of DVT. We investigate the effects of dietary IR on the thrombus formation and resolution in a rat model of DVT. Methods: We performed the ligation of inferior vena cava to induce DVT in 8-week-old male Sprague-Dawley rats. After the ligation, rats were given either a normal diet (DVT group) or iron-restricted diet (DVT+IR group). The thrombus was harvested at 5days after the ligation. Results: At first, TfR1 expression was increased in the thrombus of a rat model of DVT, suggesting that iron and TfR1 play roles in the pathogenesis of DVT. Interestingly, dietary iron restriction reduced the thrombus size compared with the DVT group (180±17 mg/cm vs 135±13 mg/cm, DVT vs DVT+IR ; p < 0.05). Intrathrombotic collagen content was diminished in the DVT+IR group compared with the DVT group. Intrathrombotic gene expression and activity of matrix metalloproteinase (MMP)-9 were increased in the DVT+IR group compared with the DVT group. In addition, the numbers of CD68 positive cells in the thrombus were fewer in the DVT+IR group than in the DVT group. Furthermore, intrathrombotic gene expression of urokinase-type plasminogen activator and tissue-type plasminogen activator was higher in the DVT+IR group than in the DVT group. Conclusions: These results suggest that iron plays a role in the pathogenesis of DVT.