title: Early treatment with hydroxychloroquine prevents the development of endothelial dysfunction in a murine model of systemic lupus erythematosus.
abstract: BACKGROUND
  Accelerated atherosclerosis is one of the major causes of morbidity in patients with systemic lupus erythematosus (SLE). Endothelial dysfunction (ED) is considered an early marker of atherosclerosis. It is a reversible alteration, thus representing an attractive target for prevention strategies against cardiovascular disease. Studies have shown that ED occurs in patients with SLE even in the absence of severe, active disease. Hydroxychloroquine (HCQ) is widely used in SLE to control disease activity, but its use is also associated with an improvement in long-term prognosis. Beyond the beneficial effect in well-established disease, our hypothesis is that treatment with HCQ might have a beneficial impact on ED prevention in SLE. The aim of this study was to assess the impact of early treatment with HCQ on ED in a murine model of SLE.
  
  
  METHODS
  Twelve-week-old NZB/W F1 (NZ) and C57BL/6 J mice (controls) were allocated to receive HCQ or vehicle for 6, 12, or 18 weeks. Proteinuria and anti-double-stranded DNA autoantibodies were determined. ED was assessed in mesenteric arteries (pressurized myography). Nitric oxide (NO) availability and reactive oxygen species (ROS) production were evaluated. Vascular ROS production was measured with dihydroethidium (DHE) fluorescent dye.
  
  
  RESULTS
  Starting from 18 weeks of age, NZ mice showed a progressive reduction in NO availability, which was normalized by ascorbic acid and apocynin in the up to 24-week-old group, and partly ameliorated in older animals. HCQ administration normalized the NO availability in the up to 24-week-old group, with a partial amelioration in the 30-week-old group. DHE analysis revealed a progressive increment of vascular ROS generation among NZ groups, which was prevented by apocynin. Similarly, in the NZ HCQ-treated group, vascular ROS production was abrogated.
  
  
  CONCLUSIONS
  The ED that characterizes this mouse model of SLE is caused by the nicotinamide adenine dinucleotide phosphate oxidase-driven ROS excess. Very early treatment with HCQ is able to exert vascular protection via an antioxidant effect.
authors.affiliation: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy. agostino.virdis@med.unipi.it.
authors.forename: Agostino
authors.initials: A
authors.lastname: Virdis
authors.affiliation: Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Via Roma, 67, 56100, Pisa, Italy. chiaratani78@gmail.com.
authors.forename: Chiara
authors.initials: C
authors.lastname: Tani
authors.affiliation: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy. e.duranti@int.med.unipi.it.
authors.forename: Emiliano
authors.initials: E
authors.lastname: Duranti
authors.affiliation: Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Via Roma, 67, 56100, Pisa, Italy. s.vagnani@tin.it.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Vagnani
authors.affiliation: Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Via Roma, 67, 56100, Pisa, Italy. 81clinda@inwind.it.|GenOMeC PhD, University of Siena, Siena, Italy. 81clinda@inwind.it.
authors.forename: Linda
authors.initials: L
authors.lastname: Carli
authors.affiliation: Medical Clinic I for Gastroenterology, Infectiology and Rheumatology, Campus Benjamin Franklin, Charité - Universitätsmedizin Berlin, Hindenburgdamm 30, D-12203, Berlin, Germany. anja.kuehl@charite.de.
authors.forename: Anja A
authors.initials: AA
authors.lastname: Kühl
authors.affiliation: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy. anna.solini@med.unipi.it.
authors.forename: Anna
authors.initials: A
authors.lastname: Solini
authors.affiliation: Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Via Roma, 67, 56100, Pisa, Italy. chiara.baldini74@gmail.com.
authors.forename: Chiara
authors.initials: C
authors.lastname: Baldini
authors.affiliation: Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Via Roma, 67, 56100, Pisa, Italy. sara.talarico76@gmail.com.
authors.forename: Rosaria
authors.initials: R
authors.lastname: Talarico
authors.affiliation: Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Via Roma, 67, 56100, Pisa, Italy. s.bombardieri@med.unipi.it.
authors.forename: Stefano
authors.initials: S
authors.lastname: Bombardieri
authors.affiliation: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy. s.taddei@int.med.unipi.it.
authors.forename: Stefano
authors.initials: S
authors.lastname: Taddei
authors.affiliation: Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Pisa, Via Roma, 67, 56100, Pisa, Italy. marta.mosca@med.unipi.it.
authors.forename: Marta
authors.initials: M
authors.lastname: Mosca
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D018501:Antirheumatic Agents / Q000494:pharmacology*; D004195:Disease Models, Animal; D004730:Endothelium, Vascular / Q000187:drug effects*; D005260:Female; D006886:Hydroxychloroquine / Q000494:pharmacology*; D008180:Lupus Erythematosus, Systemic / Q000150:complications*; D051379:Mice; D008810:Mice, Inbred C57BL; D008814:Mice, Inbred NZB; D017382:Reactive Oxygen Species / Q000378:metabolism; D014652:Vascular Diseases / Q000209:etiology* / Q000517:prevention & control
chemical_list: D000975:Antioxidants; D018501:Antirheumatic Agents; D017382:Reactive Oxygen Species; D006886:Hydroxychloroquine