Rapamycin-Loaded Biomimetic Nanoparticles Reverse Vascular Inflammation.

RATIONALE: Through localized delivery of rapamycin via a biomimetic drug delivery system, it is possible to reduce vascular inflammation and thus the progression of vascular disease. OBJECTIVE: Use biomimetic nanoparticles to deliver rapamycin to the vessel wall to reduce inflammation in an in vivo model of atherosclerosis after a short dosing schedule. METHODS AND RESULTS: Biomimetic nanoparticles (leukosomes) were synthesized using membrane proteins purified from activated J774 macrophages. Rapamycin-loaded nanoparticles were characterized using dynamic light scattering and were found to have a diameter of 108±2.3 nm, a surface charge of -15.4±14.4 mV, and a polydispersity index of 0.11 +/ 0.2. For in vivo studies, ApoE-/- mice were fed a high-fat diet for 12 weeks. Mice were injected with either PBS, free rapamycin (5 mg/kg), or rapamycin-loaded leukosomes (Leuko-Rapa; 5 mg/kg) once daily for 7 days. In mice treated with Leuko-Rapa, flow cytometry of disaggregated aortic tissue revealed fewer proliferating macrophages in the aorta (15.6±9.79 %) compared with untreated mice (30.2±13.34 %) and rapamycin alone (26.8±9.87 %). Decreased macrophage proliferation correlated with decreased levels of MCP (monocyte chemoattractant protein)-1 and IL (interleukin)-b1 in mice treated with Leuko-Rapa. Furthermore, Leuko-Rapa-treated mice also displayed significantly decreased MMP (matrix metalloproteinases) activity in the aorta (mean difference 2554±363.9, P=9.95122×10-6). No significant changes in metabolic or inflammation markers observed in liver metabolic assays. Histological analysis showed improvements in lung morphology, with no alterations in heart, spleen, lung, or liver in Leuko-Rapa-treated mice. CONCLUSIONS: We showed that our biomimetic nanoparticles showed a decrease in proliferating macrophage population that was accompanied by the reduction of key proinflammatory cytokines and changes in plaque morphology. This proof-of-concept showed that our platform was capable of suppressing macrophage proliferation within the aorta after a short dosing schedule (7 days) and with a favorable toxicity profile. This treatment could be a promising intervention for the acute stabilization of late-stage plaques.

[Aortic inflammatory lesions in Behçet's disease]. / Atteintes aortiques inflammatoires associées à la maladie de Behçet.

The arterial lesions affect about 10% of patients with Behçet's disease (BD). Aortic inflammatory involvement includes predominantly aortic aneurysmal lesions affecting most often the abdominal aorta. They account for the severity of the disease and are a leading cause of death when they hit the aorta or pulmonary arteries. Within the arterial lesions of BD, aortic involvement is, with femoral lesions, the most common site involved (18-28% of patients with vascular disease). Unlike other large vessels vasculitis (i.e. giant cell arteritis and Takayasu's arteritis) diffuse aortitis is observed in less than 5% of patients with BD. Aortic lesions of BD may be asymptomatic (systematic imaging or occasionally associated with other vascular event) or be revealed by the occurrence of abdominal, thoracic or lumbar pain, or an aortic valve insufficiency. Fever is frequently associated. Increase in acute phase reactants is common in these patients. Histological analysis may show infiltration by lymphocytes, neutrophils and plasma cells in the media and adventitia and a proliferation of the vasa vasorum in the media as well as a fibroblastic proliferation. In the later phase, a fibrous thickening of the media and adventitia is observed as well as a proliferation and thickening of the vasa vasorum. The therapeutic management should always include a medical treatment for the control of inflammation (corticosteroids, immunosuppressive drugs and/or biotherapy) and often an endovascular or surgical treatment if the aneurysm is threatening. The choice between endovascular or surgical treatment is considered case by case, depending on the experience of the team, anatomical conditions and of the clinical presentation. In this review, we provide a detailed and updated review of the literature to describe the aortic inflammatory damage associated with Behçet's disease.

Infección intravascular por Salmonella enteritidis / Intravascular infection by salmonella enteritidis

Presentamos un caso de aortitis salmonelósica en un varón de 70 años tras un episodio de gastroenteritis aguda por Salmonella enteritidis que fue tratado con éxito mediante by-pass extraanatómico y administración prolongada de ciprofloxacino (AU)