[Suppression of experimental abdominal aortic aneurysm by saturated hydrogen saline: a preliminary study with rats]

To investigate the effects of saturated hydrogen saline on the prevention of abdominal aortic aneurysm (AAA) induced by calcium chloride in a rat model.

In healthy male Sprague-Dawley rats, AAA was induced by infiltration of abdominal arota with 0.5 mol/L calcium chloride. Saturated hydrogen saline (5 ml·kg(-1)·d(-1)) or saline was administred intraperitoneally once daily. Twenty-eight days later, the diameter of the aorta was measured, and the aortic tissue was exercised for histological examination. Pro-inflammatory cytokines (tumor necrosis factor α (TNF-α), IL-1β) in AAA tissue were detected with ELISA. The protein expression and mRNA expression of matrix metalloproteinase 2 (MMP-2) and MMP-9 in AAA tissue were observed by immunohistochemistry staining and real-time PCR.

The aorta diameter of the experiment group and control group were (2.2 ± 0.3) mm and (3.4 ± 0.5) mm, the tissue IL-1β levels were (81 ± 29) ng/L and (165 ± 51) ng/L, the tissue TNF-α levels were (109 ± 46) ng/L and (360 ± 51) ng/L, the relative mRNA expressions were 2.4 ± 1.0 and 11.8 ± 2.9, the relative mRNA expressions were 2.9 ± 0.6 and 6.7 ± 1.0 (t = 4.055 to 10.406, P < 0.05). Compared with the control group, the infiltration of inflammation, the injury of elastic fibers in the vessel wall, and the positive expression of MMP-2 and 9 protein of the experiment group were all reduced.

Saturated hydrogen saline prevents the degradation of elastin in vessel wall and ameliorates the formation and development of AAA, which may be associated with its anti-inflammatory effects, thereby reduces the MMP-2 and 9 mRNA and protein expression.