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LDE-carmustine treatment resulted in marked reduction of lesion area, of the invasion of the arterial intima by macrophages and vascular smooth muscle cells and pro-inflammatory factors. Therefore, this new formulation shows great potential for therapy of atherosclerotic cardiovascular disease.

SUMMARY HIV+ patients often develop alterations of the plasma lipids that may implicate in development of premature coronary artery disease. High-density lipoprotein (HDL) has an important role in preventing atherogenesis and the aim of this study was to investigate aspects of HDL function in HIV + patients. HIV + patients (n = 48) and healthy control subjects (n = 45) of both sexes with similar age were studied. Twenty-five were not being treated with antiretroviral agents, 13 were under reverse transcriptase inhibitor nucleosidic and non-nucleosidic (NRTI+NNRTI) and 10 were under NRTI + protease inhibitors (NRTI+PI) treatment. Paraoxonase 1 (PON1) activity and the transfer of free and esterified cholesterol, tryglicerides and phospholipids from a lipidic nanoemulsion to HDL were analyzed. In comparison with healthy controls, HIV + patients presented low PON-1 activity and diminished transfer of free cholesterol and tryglicerides. In contrast, phospholipid transfer was increased in those patients, whereas the transfer of cholesteryl esters was unchanged. NRTI+NNRTI increases the transfer of cholesteryl esters and triglycerides but in NRTI+PI there was no difference in respect to non-treated HIV + patients. HDL from HIV + patients has smaller antioxidant properties, as shown by lower PON-1 activity, and the transfer of lipids to this lipoprotein fraction is also altered, suggesting that HDL function is defective in those patients.

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AGRADECIMENTOSAo Prof. Dr. Raul C. Maranhão, pela orientação, confiança, oportunidade de realizar este trabalho e a excepcional possibilidade de estudar fora do País, um período que contribuiu muito para o meu crescimento pessoal e, principalmente, profissional. Obrigada pelo valioso ensinamento durante esta importante trajetória.

After injection in bloodstream, a lipid nanoemulsion (LDE) resembling low-density lipoprotein (LDL) concentrate in atherosclerotic lesions of cholesterol-fed rabbits. Here, rabbits with atherosclerosis were treated with carmustine, an antiproliferative agent used in cancer chemotherapy, associated to LDE to investigate the effects on the lesions. Eighteen male New Zealand rabbits were fed a 1% cholesterol diet for 8 weeks. After 4 weeks nine animals were treated intravenous saline solution and nine with intravenous LDE-carmustine (4 mg/kg, weekly for 4 weeks). LDE-carmustine inhibited atherosclerotic lesions by 90%, compared to controls. LDE-carmustine reduced presence of macrophages, smooth muscle cells, and regulatory T-cells in the arterial intima as well as the expression of matrix metallopeptidase-9, interleukin-1β and TNF-α and lipoprotein receptors (LDL receptor, LDL-related protein-1 and scavenger receptor class B member 1). In conclusion, LDE-carmustine treatment resulted in marked reduction of lesion area, invasion by macrophages and intimal smooth muscle cells and pro-inflammatory factors. Therefore, this new formulation shows great potential for therapy of atherosclerotic cardiovascular disease.

Lipid core nanoparticles (LDE) resembling LDL behave similarly to native LDL when injected in animals or subjects. In contact with plasma, LDE acquires apolipoproteins (apo) E, A-I and C and bind to LDL receptors. LDE can be used to explore LDL metabolism or as a vehicle of drugs directed against tumoral or atherosclerotic sites. The aim was to investigate in knockout (KO) and transgenic mice the plasma clearance and tissue uptake of LDE labeled with H-cholesteryl ether. LDE clearance was lower in LDLR KO and apoE KO mice than in wild type (WT) mice (p< 0.05). However, infusion of human apoE3 into the apoE KO mice increased LDE clearance. LDE clearance was higher in apoA-I KO than in WT. In apoA-I transgenic mice, LDE clearance was lower than in apoA-I KO and than in apoA-I KO infusion with human HDL. Infusion of human HDL into the apoA-I KO mice resulted in higher LDE clearance than in the apoA-I transgenic mice (p < 0.05). In apoA-I KO and apoA-I KO infused human HDL, the liver uptake was greater than in WT animals and apoA-I transgenic animals (p < 0.05). LDE clearance was lower in apoE/A-I KO than in WT. Infusion of human HDL increased LDE clearance in those double KO mice. No difference among the groups in LDE uptake by the tissues occurred. In conclusion, results support LDLR and apoE as the key players for LDE clearance, apoA-I also influences those processes.