Ovariectomy and Chemical Ovarian Failure Exacerbate Atherosclerosis without Impairing Limb Recovery in Experimental Peripheral Artery Disease
BackgroundPeripheral artery disease is a major manifestation of atherosclerotic cardiovascular disease (ASCVD) that affects both men and women. In women, menopause increases the ASCVD risk. However, preclinical ASCVD research has historically been conducted predominantly in males, with relatively few studies focused on females and even fewer incorporating menopause models that more closely reflect human ASCVD pathobiology. Herein, we tested whether the chemical 4-vinylcyclohexene diepoxide (4-VCD)-induced ovarian failure or ovariectomy (OVX) would drive atherosclerotic development and worsen ischemic limb pathophysiology. MethodsFemale C57BL/6J mice were injected with adeno-associated virus-mediated encoding a gain-of-function mutant PCSK9 and fed an atherogenic diet for 23 weeks. Based on the baseline body weight, mice were randomly assigned to normally cycling controls (CON), 4-VCD, or OVX groups. Three weeks after the conformation of ovarian failure (4-VCD) or surgical ovarian removal (OVX), hindlimb ischemia (HLI) was induced via femoral artery ligation, and limb perfusion recovery and limb muscle performance were assessed. ResultsBoth 4-VCD treatment and OVX reduced uterus mass, without impacting body weight or composition, or circulating cholesterol levels compared to CON mice. Despite the similar metabolic and cholesterol profiles, atherosclerotic lesion areas were 1.5-1.7-fold greater in 4-VCD and OVX mice than CON mice. Perfusion recovery following HLI and plantar flexor muscle function in the ischemic limb were similar across groups, though muscle oxygenation was reduced in 4-VCD and OVX groups. ConclusionsOvarian failure and removal exacerbated atherosclerotic development but had minimal impacts on perfusion recovery and limb function following HLI. These findings confirm the inclusion of menopausal models, whether through ovarian failure or OVX, should be carefully considered to improve translatability of preclinical ASCVD studies, especially for womens health. Clinical PerspectiveO_ST_ABSWhat is New?C_ST_ABSWe demonstrate that both gradual ovarian failure (4-VCD) and surgical ovariectomy exacerbate atherosclerotic plaque development in a clinically relevant AAV-PCSK9 model, despite similar circulating lipid levels. In contrast, loss of ovarian function did not impair limb perfusion recovery or muscle functional outcomes following hindlimb ischemia, revealing a dissociation between atherosclerotic burden and limb functional recovery in experimental peripheral artery disease (PAD). What are the Clinical Implications?These findings provide new insight into why menopause increases atherosclerotic cardiovascular disease (ASCVD) risk while not necessarily demonstrating proportional impairments in limb recovery following ischemia. The data suggest that menopause-associated factors accelerate large-vessel atherosclerosis independent of circulating lipids, highlighting the need for targeted therapies beyond lipid lowering in postmenopausal women. Moreover, the dissociation between plaque burden and ischemic limb function underscores the importance of assessing functional outcomes in PAD independently of vascular imaging. Finally, these findings suggest that the incorporation of menopause-relevant models in preclinical research should be considered within the context of the specific biological endpoints and translational goals being evaluated.