Dietary DNA Attenuates the Degradation of Elastin Fibers in the Aortic Wall in Nicotine-Administrated Mice

: Abdominal aortic aneurysm (AAA) is a vascular disease characterized by chronic inflammation in the infrarenal aorta. Epidemiologic data have clearly linked tobacco smoking to aneurysm formation and a faster rate of expansion. It suggested that nicotine, one of the main ingredients of tobacco, has been suggested to be associated with AAA development and rupture. In the condition where no established drugs are available; therefore, an effective approach to prevent the vascular damage from nicotine consumption may be the use of dietary functional food factors. However, little is known about the relationship between dietary components and AAA. In this study, we estimated the effect of dietary deoxyribonucleic acid (DNA) on the vascular wall. After habituation for 5 d, the mice were divided into four groups: control diet and distilled water group (C), DNA-Na diet and distilled water group (DNA), control diet and 0.5 mg/mL nicotine solution group (C-Nic), DNA-Na diet, and 0.5 mg/mL nicotine solution group (DNA-Nic). The dietary DNA attenuated the degradation of elastin fibers induced by nicotine administration. The areas stained positive for MMP-2 in the DNA-Nic group were significantly suppressed compared to C-Nic mice. These data suggest that the dietary DNA may prevent the weakening of the aortic wall via inhibition of the MMP-2-dependent pathway. In conclusion, we have revealed the protective effect of dietary DNA on the vascular pathology of nicotine-administrated mice. A nucleic acid-rich diet might be useful for people who consume nicotine via smoking, chewing tobacco, or nicotine patches.