A bdominal aortic aneurysm (AAA) is a common vascular disease, which occurs in ≈4% to 8% of men aged 65 to 80 years.1 Aortic rupture is the most feared clinical consequence of AAA progression, resulting in mortality in ≈90% of cases. [2][3][4] Because AAA usually progresses without symptoms, AAA is often discovered in advanced stage. At present, surgical aortic replacement and endovascular stent graft repair are performed as standard definitive therapies for AAA. However, there is no effective medical therapy to prevent aortic rupture in AAA. Although several studies have reported the pathophysiology of AAA, the mechanisms of AAA formation are largely unknown. Therefore, it is necessary to investigate the molecular pathophysiology of AAA to find noninvasive strategies for the prevention of AAA.Iron is an essential element for maintaining physiological function. However, excess iron causes tissue damage by oxidative stress via the Fenton/Haber-Weiss reaction. 5Therefore, iron is involved in the pathophysiology of several diseases including cardiovascular diseases. In fact, we have previously shown that iron accumulation and superoxide production are observed in the renal tubules of a rat model of chronic kidney disease.6 Lee et al 7 have shown that iron accumulation is observed in the atherosclerotic lesions of apolipoprotein E knockout mice. Most recently, Martinez-Pinna et al 8 have demonstrated that iron is deposited in human AAA walls. Meanwhile, we have also reported that dietary iron restriction (IR) prevents the development of hypertension and proteinuria with inhibition of oxidative stress and inflammation in Dahl salt-sensitive hypertensive rats.9 Although oxidative stress and inflammation are well known to be involved in the development of AAA formation, it has not been investigated whether iron is associated with the pathophysiology of AAA through © 2015 American Heart Association, Inc. Objective-Although iron is an essential element for maintaining physiological function, excess iron leads to tissue damage caused by oxidative stress and inflammation. Oxidative stress and inflammation play critical roles for the development of abdominal aortic aneurysm (AAA). However, it has not been investigated whether iron plays a role in AAA formation through oxidative stress and inflammation. We, therefore, examined whether iron is involved in the pathophysiology of AAA formation using human AAA walls and murine AAA models. Approach and Results-Human aortic walls were collected from 53 patients who underwent cardiovascular surgery (non-AAA=34; AAA=19). Murine AAA was induced by infusion of angiotensin II to apolipoprotein E knockout mice. Iron was accumulated in human and murine AAA walls compared with non-AAA walls. Immunohistochemistry showed that both 8-hydroxy-2′-deoxyguanosine and CD68-positive areas were increased in AAA walls compared with non-AAA walls. The extent of iron accumulated area positively correlated with that of 8-hydroxy-2′-deoxyguanosine expression area and macrophage infiltration area in huma...

Iron accumulation is associated with the pathophysiology of chronic kidney disease (CKD). Renal fibrosis is a final common feature that contributes to the progression of CKD; however, little is known about the association between renal iron accumulation and renal interstitial fibrosis in CKD. Here we investigate the effects of iron chelation on renal interstitial fibrosis in a rat model of CKD. CKD was induced by 5/6 nephrectomy in Sprague-Dawley rats. At 8 weeks after operation, 5/6 nephrectomized rats were administered an oral iron chelator, deferasirox (DFX), in chow for 8 weeks. Other CKD rats were given a normal diet. Sham-operative rats given a normal diet served as a control. CKD rats exhibited hypertension, glomerulosclerosis and renal interstitial fibrosis. Iron chelation with DFX did not change hypertension and glomerulosclerosis; however, renal interstitial fibrosis was attenuated in CKD rats. Consistent with these findings, renal gene expression of collagen type III and transforming growth factor-β was increased in CKD rats compared with the controls, while iron chelation suppressed these increments. In addition, a decrease in vimentin along an increase in E-cadherin in renal gene expression was observed in CKD rats with iron chelation. CKD rats also showed increased CD68-positive cells in the kidney, whereas its increase was attenuated by iron deprivation. Similarly, increased renal gene expression of CD68, tumor necrosis factor-α and monocyte chemoattractant protein-1 was suppressed in CKD rats with iron chelation. Renal iron accumulation seems to be associated with renal interstitial fibrosis in a rat model of CKD.

Objective Oral anticoagulants (OACs), which include direct oral anticoagulants (DOACs) and warfarin, are widely used for the prevention of thromboembolic events in patients with atrial fibrillation (AF). Cancer is associated with a prothrombotic state as well as an increased bleeding risk. Few data are available on the efficacy and safety of OACs in Japanese cancer patients with AF. We sought to investigate the efficacy and safety of OACs in this population. Methods This retrospective cohort study included active cancer patients in whom AF was recorded by electrocardiography in our hospital from January 2014 to December 2016 and who were treated with DOACs or warfarin. Patients were followed for 1 year. The study outcomes were stroke or systemic embolism and major bleeding. Result A total of 224 patients with AF and active cancer were treated with OACs (DOACs, n=127; warfarin, n=97). Overall, stroke or systemic embolism and major bleeding occurred in seven (3.8%/year) and eight (4.9%/year) patients, respectively. Stroke or systemic embolism occurred in three patients in the DOAC group (2.8%/year) and four patients in the warfarin group (5.4%/year). Major bleeding occurred in four patients in the DOAC group (4.0%/year) and four patients in the warfarin group (6.5%/year). Conclusion The rates of stroke or systemic embolism and major bleeding events were not negligible among Japanese cancer patients with AF receiving OACs. Further investigations on the optimal management of Japanese patients with AF and cancer are needed.

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