Long-term effect of PROLI/NO on cellular proliferation and phenotype after arterial injury

• Published in: Free radical biology & medicine 2016-01, Vol.90, p.272-286
• Main Authors: Bahnson, Edward S.M., Vavra, Ashley K., Flynn, Megan E., Vercammen, Janet M., Jiang, Qun, Schwartz, Amanda R., Kibbe, Melina R.
• Format: Article
• Language: English
• Subjects: Actins - analysis; Animals; Apoptosis - drug effects; Arteries - injuries; Carotid Artery Injuries - pathology; Cell Proliferation - drug effects; Hyperplasia; Inflammation; Male; Muscle, Smooth, Vascular - cytology; Muscle, Smooth, Vascular - drug effects; Myocytes, Smooth Muscle - drug effects; Myocytes, Smooth Muscle - physiology; Neointima - pathology; Neointimal hyperplasia; Nitric oxide; Nitric Oxide Donors - pharmacology; Phenotype; Proliferation; Proline - analogs & derivatives; Proline - pharmacology; Rats; Rats, Sprague-Dawley; Reactive nitrogen species; S-nitrosation
• ISSN: 0891-5849; 1873-4596
• DOI: 10.1016/j.freeradbiomed.2015.11.027

Vascular interventions are associated with high failure rates from restenosis secondary to negative remodeling and neointimal hyperplasia. Periadventitial delivery of nitric oxide (NO) inhibits neointimal hyperplasia, preserving lumen patency. With the development of new localized delivery vehicles, NO-based therapies remain a promising therapeutic avenue for the prevention of restenosis. While the time course of events during neointimal development has been well established, a full characterization of the impact of NO donors on the cells that comprise the arterial wall has not been performed. Thus, the aim of our study was to perform a detailed assessment of proliferation, cellularity, inflammation, and phenotypic cellular modulation in injured arteries treated with the short-lived NO donor, PROLI/NO. PROLI/NO provided durable inhibition of neointimal hyperplasia for 6 months after arterial injury. PROLI/NO inhibited proliferation and cellularity in the media and intima at all of the time points studied. However, PROLI/NO caused an increase in adventitial proliferation at 2 weeks, resulting in increased cellularity at 2 and 8 weeks compared to injury alone. PROLI/NO promoted local protein S-nitrosation and increased local tyrosine nitration, without measurable systemic effects. PROLI/NO predominantly inhibited contractile smooth muscle cells in the intima and media, and had little to no effect on vascular smooth muscle cells or myofibroblasts in the adventitia. Finally, PROLI/NO caused a delayed and decreased leukocyte infiltration response after injury. Our results show that a short-lived NO donor exerts durable effects on proliferation, phenotype modulation, and inflammation that result in long-term inhibition of neointimal hyperplasia. •This protection depends upon the diazeniumdiolate moiety as proline has no effect.•Periadventitial delivery of this NO donor, significantly increased plasma nitrite. However, it caused neither a drop in blood pressure, nor an increase in plasma S-nitrosothiols. Periadventitial delivery of PROLI/NO increased plasma nitrite with no side effects.•PROLI/NO inhibited proliferation and cellularity in the media and intima.•However, it caused an increase in adventitial proliferation and cellularity.•PROLI/NO inhibited contractile smooth muscle cells in the intima and media.•PROLI/NO caused a delayed and decreased leukocyte infiltration response after injury.•Periadventitial PROLI/NO locally affects S-nitrosation and protein nit