Intermittent oral supplementation with fisetin improves arterial function in doxorubicin chemotherapy-treated mice by suppressing cellular senescence
Authors: Darrah Mary , Mahoney Sophia , Venkatasubramanian Ravinandan , VanDongen Nicholas , Ludwig Katelyn , Rossman Matthew , Seals Douglas 
Published: May 2024

Introduction. Arterial dysfunction (endothelial dysfunction and aortic stiffening) is a key antecedent to the development of cardiovascular diseases. Cellular senescence, a state of nearly irreversible cell cycle arrest, develops in arteries following doxorubicin (Doxo) chemotherapy treatment and induces arterial dysfunction. Fisetin is a natural senolytic (senescent cell clearing compound) that improves arterial function in old mice. However, it is unknown if fisetin supplementation can decrease cellular senescence to reverse Doxo-induced arterial dysfunction. Purpose. To determine if fisetin supplementation can improve arterial function following Doxo treatment by decreasing cellular senescence. Methods & Results. Cell culture. Human aortic endothelial cells were treated with fisetin for 48 hr (0.25, 0.5, 1 uM) following Doxo-induced cellular senescence (200 nm Doxo for 48 hr). 1 uM fisetin lowered senescence burden (senescence-associated β-galactosidase staining) by ~50% ( P = 0.0003). Animals. Young adult (4 mo) male/female p16-3MR mice received Doxo (10 mg/kg) or sham (saline) intraperitoneally. Four weeks later (established time-point of Doxo-induced arterial dysfunction), animals were treated daily with vehicle (V; 10% EtOH, 30% PEG400, 60% Phosal 50 PG) or fisetin (F; 100 mg/kg) via oral gavage using an intermittent 1 week on - 2 weeks off - 1 week on dosing paradigm, yielding 4 groups (Sham-V; Sham-F; Doxo-V; Doxo-F). Data from Sham-V and Sham-F groups were similar for all outcomes. Data are combined due to no sex differences. Endothelial function. Endothelial function (carotid artery endothelium dependent dilation [EDD] to acetylcholine [ACh]) and nitric oxide (NO)-mediated EDD (± L-NAME) were measured following fisetin (or vehicle) supplementation. Doxo-V mice had lower peak EDD relative to Sham-V (73 ± 2 v. 89 ± 2 %; P = 0.003), and this difference was ameliorated in Doxo-F animals (88 ± 3 %). Likewise, Doxo-V mice had lower NO-mediated EDD compared to Sham-V (39 ± 7% v. 55 ± 8%, P = 0.047), and this difference was ameliorated in Doxo-F mice (66 ± 7%). Incubation of carotid arteries ex vivo with ganciclovir (GCV) to clear p16+ senescent cells in p16-3MR mice normalized peak EDD (Sham-V, 93 ± 1; Doxo-V, 93 ± 2; Doxo-F, 91 ± 2%), suggesting that reducing cellular senescence is the mechanism by which fisetin supplementation improved endothelial function. Aortic stiffness. The Doxo-induced increase in aortic stiffness (aortic pulse wave velocity [PWV]) (Doxo-V, 426 ± 20 vs. Sham-V, 332 ± 5 cm/sec; P < 0.0001) was reversed following fisetin supplementation in Doxo-F mice (pre-fisetin: 426 ± 10 v. post-fisetin: 345 ± 5 cm/sec; P = 0.001). The differences in PWV were associated with corresponding differences in ex vivo aortic intrinsic mechanical wall stiffness (Doxo-V, 5991 ± 362 v. Doxo-F, 3996 ± 415 vs. Sham-V, 4813 ± 133 kPa; P = 0.010). Ex vivo incubation of aorta rings with GCV for 48h ameliorated group differences in aortic intrinsic mechanical wall stiffness, suggesting a causal role for suppression of cellular senescence in the response. Conclusion: Intermittent fisetin supplementation may be a novel strategy to favorably modulate cellular senescence, a key cellular signaling pathway mediating arterial dysfunction with Doxo chemotherapy. R21 AG078408 & K99 HL159241. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.