Chronic treatment with dill extract preserves elastic lamellae integrity and induces elastic fibers neosynthesis in the abdominal aorta of adult and aged male and female mice

Abstract

Elastic fibers are extracellular matrix components made of elastin (90%) and microfibrils (10%). Elastin is synthesized primarily in early life and confers to the large elastic arteries the property of elasticity, allowing storage of energy and stroke volume during the systole, then release of energy and blood volume during the diastole. This phenomenon helps to decrease the load on the heart. With aging, elastin is progressively degraded, leading to arterial stiffening and dysfunction. In a previous study we showed that chronic administration of Dill Extract at 5% or 10% v/v administered in drink water could be considered as an anti-aging product for the cardiovascular system but with different pathways. If 5% and 10% DE treatment increased tropoelastin and LOXL1 expressions in the aorta and induced the neo-synthesis of elastic fibers in the aortic wall of DE-treated aged mice and both had a reversal effect on aged related cardiac hypertrophy, surprisingly, blood pressure was decreased only with 5% DE and has no effect on mechanics properties of ascending aorta contrary to 10% DE. So, we decided to investigate further the effect of 5% DE. In this study, we explored the effects on elastin production (Elisa and histology) and large artery elasticity (pressure arteriography) in aged and adult mice of both genders. In opposite of the previous study, we investigate the effect of DE on the abdominal aorta which has different developmental origins, which could explain the different reaction to DE doses. We showed that chronic treatment with dill extract reduced the age-related cardiac hypertrophy only in male mice and re-induced elastic fibers formation, even in aged animals. Moreover, dill extract-treated mice exhibited increased arterial distensibility, especially in female mice. Our results suggest that dill extract presents an interesting potential for arterial function improvement in an anti-aging perspective, even when treating aged animals.