OBJECTIVE:The toxicity of anti-cancer chemotherapeutic agents can be reduced by associating these compounds, such as the anti-proliferative agent paclitaxel, with a cholesterol-rich nanoemulsion (LDE) that mimics the lipid composition of low-density lipoprotein (LDL). When injected into circulation, the LDE concentrates the carried drugs in neoplastic tissues and atherosclerotic lesions. In rabbits, atherosclerotic lesion size was reduced by 65% following LDE-paclitaxel treatment. The current study aimed to test the effectiveness of LDE-paclitaxel on inpatients with aortic atherosclerosis.METHODS:This study tested a 175 mg/m2 body surface area dose of LDE-paclitaxel (intravenous administration, 3/3 weeks for 6 cycles) in patients with aortic atherosclerosis who were aged between 69 and 86 yrs. A control group of 9 untreated patients with aortic atherosclerosis (72-83 yrs) was also observed.RESULTS:The LDE-paclitaxel treatment elicited no important clinical or laboratory toxicities. Images were acquired via multiple detector computer tomography angiography (64-slice scanner) before treatment and at 1-2 months after treatment. The images showed that the mean plaque volume in the aortic artery wall was reduced in 4 of the 8 patients, while in 3 patients it remained unchanged and in one patient it increased. In the control group, images were acquired twice with an interval of 6-8 months. None of the patients in this group exhibited a reduction in plaque volume; in contrast, the plaque volume increased in three patients and remained stable in four patients. During the study period, one death unrelated to the treatment occurred in the LDE-paclitaxel group and one death occurred in the control group.CONCLUSION:Treatment with LDE-paclitaxel was tolerated by patients with cardiovascular disease and showed the potential to reduce atherosclerotic lesion size.

Oxysterols are cholesterol oxygenated derivatives which possess several biological actions. Among oxysterols, 7-ketocholesterol (7KC) is known to induce cell death. Here, we hypothesized that 7KC cytotoxicity could be applied in cancer therapeutics. 7KC was incorporated into a lipid core nanoemulsion. As a cellular model the murine melanoma cell line B16F10 was used. The nanoparticle (7KCLDE) uptake into tumor cells was displaced by increasing amounts of low-density-lipoproteins (LDL) suggesting a LDL-receptor-mediated cell internalization. 7KCLDE was mainly cytostatic, which led to an accumulation of polyploid cells. Nevertheless, a single dose of 7KCLDE killed roughly 10% of melanoma cells. In addition, it was observed dissipation of the transmembrane potential, evidenced with flow cytometry; presence of autophagic vacuoles, visualized and quantified with flow cytometry and acridine orange; and presence of myelin figures, observed with ultrastructural microscopy. 7KCLDE impaired cytokenesis was accompanied by changes in cellular morphology into a fibroblastoid shape which is supported by cytoskeletal rearrangements, as shown by the increased actin polymerization. 7KCLDE was injected into B16 melanoma tumor-bearing mice. 7KCLDE accumulated in the liver and tumor. In melanoma tumor 7KCLDE promoted a >50% size reduction, enlarged the necrotic area, and reduced intratumoral vasculature. 7KCLDE increased the survival rates of animals, without hematologic or liver toxicity. Although more pre-clinical studies should be performed, our preliminary results suggested that 7KCLDE is a promising novel preparation for cancer chemotherapy.

FH elicited marked changes in three of the four tested lipid transfers to HDL. The entry of UC into HDL for subsequent esterification is an important driving force for RCT and reduction of UC transfer to HDL was previously associated to precocious coronary heart disease. Therefore, in FH, HDL functions can be lessened, which can also contribute to atherogenesis.

Dyslipidemia may influence enzymes and transfer proteins needed to the lipoprotein particle remodeling. Calculated indices and evaluation of lipoprotein particle size have widely been used to predict cardiovascular risk. The aim of this study was to evaluate HDL particle size and LDL particle size estimate based on TG/HDL-C as well as apoB/apoA-I ratio as possible marker and atherogenic indices, respectively, of cardiovascular disease risk in the presence of dyslipidemia. We evaluated 100 individuals of both gender, without treatment with lipid-lowering drugs, 27 normolipidemic and 73 dyslipidemic, such as isolated hypercholesterolemia (n = 16), isolated A. P. C. Santos et al. 25hypertriglyceridemia (n = 17), low HDL-C (n = 26) and mixed dyslipidemia (n = 14). The HDL particle size did not differ between groups. The TG/HDL-C ratio was higher in groups with isolated hypertriglyceridemia (4.2 ± 1.5), low HDL-C (5.2 ± 3.1) and mixed dyslipidemia (5.3 ± 1.6). The apoB/apoA-I ratio was increased in all groups of dyslipidemia (apoB/apoA-I > 0.5) when compared to normolipidemic (apoB/apoA-I = 0.5, p < 0.001). There was a positive linear correlation between the TG/HDL-C ratio and the apoB/apoA-I ratio in low HDL-C group (r = 0.507, p = 0.008, Spearman). The results suggest that the evaluations of lipoproteins particles remodeling markers and the use of calculated indices may contribute to the evaluation of cardiovascular disease risk when dyslipidemia take place.

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