KMID : 0043320120350050877
|
|
Archives of Pharmacal Research 2012 Volume.35 No. 5 p.877 ~ p.886
|
|
Attenuation of aortic injury by ursolic acid through RAGE-Nox-NF¥êB pathway in streptozocin-induced diabetic rats
|
|
Xiang Min
Wang Jianmei Zhang Yaqin Ling Jing Xu Xiaoyue
|
|
Abstract
|
|
|
Vascular complications are the leading causes of morbidity and mortality in diabetes mellitus (DM). The RAGE (receptor for advanced glycation end products)-NADPH oxidase-NF-¥êB signal transduction pathway plays an important role in the development of oxidative stress-related vascular complications in DM. Ursolic acid (UA), a pentacyclic triterpenoid derived from plants, has been reported to have multiple pharmacological effects, including a potent antioxidant activity. This study aimed to investigate both the effect of UA on aortic injury in streptozotocin (STZ)-induced diabetic rats and the drug¡¯s mechanism of action. STZ-induced diabetic animals were randomized in one of the following 4 groups: no treatment (diabetic model group), aminoguanidine (AG, 100 mg/kg), high-dose UA (50 mg/kg), and low-dose UA (25 mg/kg). A non-diabetic control group was followed concurrently. After 8 weeks, the diabetic model rats exhibited: severe aortic arch injury, histologically elevated serum glucose, fructosamine, and glycosylated hemoglobin; and accumulation of advanced glycation end products (AGEs) in the arota. In addition, the levels of RAGE protein, transcription factor NF-¥êB p65, and the p22phox subunit of NADPH oxidase were increased, as were the serum levels of malondialdehyde and tumor necrosis factor-alpha (TNF-¥á; p < 0.01 vs control), suggesting that the mechanisms of oxidative stress contributed to vascular injury in the diabetic model group. In contrast, rats treated with UA (50 mg/kg) had a markedly less vascular injury and significantly improved biochemical parameters. Oxidative balance was also normalized in the UA-treated rats, and a marked reduction in the levels of RAGE and p22phox paralleled the reduced activation of NF-¥êB p65 and TNF-¥á (p < 0.01 and p < 0.05, respectively, vs diabetic model). These findings suggest that UA may suppress oxidative stress, thus blunting activation of the RAGE-NADPH oxidase-NF-¥êB signal transduction pathway, to ameliorate vascular injury in the STZ-induced DM rats.
|
|
KEYWORD
|
|
NF-¥êB, Oxidative stress, p22phox, RAGE, Ursolic acid, Vascular complications
|
|
FullTexts / Linksout information
|
|
|
|
Listed journal information
|
|
|
|