BACKGROUND: Aging is a risk factor for atherosclerosis. Recent studies suggest cell cycle events as well as reactive oxygen species (ROS) contribute to vascular cell dysfunction associated with aging. Mice expressing low levels of the spindle assembly checkpoint protein BubR1 develop aging-associated vascular changes at a young age, including decreased smooth muscle cells and increased reactive oxygen species (ROS) production. This study was designed to determine the effect of aging and production of oxygen-derived free radicals on expression of BubR1. MATERIALS AND METHODS: To assess cell proliferation capacity, human aortic smooth muscle cells (hAoSMC) derived from a young group (17-30 y) or an aged group (57-62 y) were cultured, and cell numbers were directly counted in using a Neubauer chamber. RT-PCR assay was used to evaluate BubR1 expression in cultured hAoSMC stimulated with Angiotensin II or H(2)O(2). RESULTS: No significant difference in BubR1 expression or hAoSMC proliferative ability was demonstrated at passage 5, but both were significantly decreased at passage 8 in the aged hAoSMC. Angiotensin II and H(2)O(2) up-regulated BubR1 expression in young hAoSMC, and the up-regulation was abrogated by a p38 MAPK inhibitor or an inhibitor of the NADH/NADPH oxidase. siRNA against BubR1 reduced proliferative activity and increased ROS production in hAoSMC. CONCLUSIONS: These findings demonstrate BubR1 mRNA expression decreases along with proliferation in aged hAoSMC. Aging-related loss of BubR1 and subsequent impairment of reactivity to ROS may explain reduced proliferative capacity of aged smooth muscle cells.
BACKGROUND: Aging is a risk factor for atherosclerosis. Recent studies suggest cell cycle events as well as reactive oxygen species (ROS) contribute to vascular cell dysfunction associated with aging. Mice expressing low levels of the spindle assembly checkpoint protein BubR1 develop aging-associated vascular changes at a young age, including decreased smooth muscle cells and increased reactive oxygen species (ROS) production. This study was designed to determine the effect of aging and production of oxygen-derived free radicals on expression of BubR1. MATERIALS AND METHODS: To assess cell proliferation capacity, human aortic smooth muscle cells (hAoSMC) derived from a young group (17-30 y) or an aged group (57-62 y) were cultured, and cell numbers were directly counted in using a Neubauer chamber. RT-PCR assay was used to evaluate BubR1 expression in cultured hAoSMC stimulated with Angiotensin II or H(2)O(2). RESULTS: No significant difference in BubR1 expression or hAoSMC proliferative ability was demonstrated at passage 5, but both were significantly decreased at passage 8 in the aged hAoSMC. Angiotensin II and H(2)O(2) up-regulated BubR1 expression in young hAoSMC, and the up-regulation was abrogated by a p38 MAPK inhibitor or an inhibitor of the NADH/NADPH oxidase. siRNA against BubR1 reduced proliferative activity and increased ROS production in hAoSMC. CONCLUSIONS: These findings demonstrate BubR1 mRNA expression decreases along with proliferation in aged hAoSMC. Aging-related loss of BubR1 and subsequent impairment of reactivity to ROS may explain reduced proliferative capacity of aged smooth muscle cells.
Authors: Carmine Izzo; Albino Carrizzo; Antonia Alfano; Nicola Virtuoso; Mario Capunzo; Mariaconsiglia Calabrese; Eros De Simone; Sebastiano Sciarretta; Giacomo Frati; Marco Oliveti; Antonio Damato; Mariateresa Ambrosio; Francesco De Caro; Paolo Remondelli; Carmine Vecchione Journal: Int J Mol Sci Date: 2018-02-06 Impact factor: 5.923
Authors: Carine Poussin; Marco van der Toorn; Sophie Scheuner; Romain Piault; Athanasios Kondylis; Rebecca Savioz; Rémi Dulize; Dariusz Peric; Emmanuel Guedj; Fabio Maranzano; Celine Merg; Moran Morelli; Anne-Laure Egesipe; Stéphanie Johne; Shoaib Majeed; Claudius Pak; Thomas Schneider; Walter K Schlage; Nikolai V Ivanov; Manuel C Peitsch; Julia Hoeng Journal: Arch Toxicol Date: 2021-07-27 Impact factor: 5.153