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Introduction: The association between high-density lipoprotein cholesterol (HDLc) with the incidence and progression of breast cancer (BC) is controversial. HDL removes excess cholesterol from cells and acts as an antioxidant and anti-inflammatory. BC is a heterogeneous disease, and its molecular classification is important in the prediction of clinical and therapeutic evolution. Triple-negative breast cancer (TNBC) presents higher malignancy, lower therapeutic response, and survival rate. In the present investigation, the composition and antioxidant activity of isolated HDL was assessed in women with TNBC compared to controls. Methods: Twenty-seven women with a recent diagnosis of TNBC, without prior treatment, and 27 healthy women (control group) paired by age and body mass index (BMI) were included in the study. HDL and low-density lipoprotein (LDL) were isolated from plasma by discontinuous density gradient ultracentrifugation. Plasma lipid profile and HDL composition (total cholesterol, TC; triglycerides, TG; HDLc; phospholipids, PL) were determined by enzymatic colorimetric methods. ApoB and apo A-I were quantified by immunoturbidimetry. The antioxidant activity of HDL was determined by measuring the lag time phase for LDL oxidation and the maximal rate of conjugated dienes formation in LDL incubated with copper sulfate solution. The absorbance (234 nm) was monitored at 37°C, for 4 h, at 3 min intervals. Results: The control group was similar to the TNBC concerning menopausal status, concentrations, and ratios of plasma lipids. The composition of the HDL particle in TC, TG, PL, and apo A-I was also similar between the groups. The ability of HDL to retard LDL oxidation was 22% greater in the TNBC group as compared to the control and positively correlated with apoA-I in HDL. Moreover, the antioxidant activity of HDL was greater in the advanced stages of TNBC (stages III and IV) compared to the control group. The maximum rate of formation of conjugated dienes was similar between groups and the clinical stages of the disease. Discussion: The results highlight the role of HDL as an antioxidant defense in TNBC independently of HDLc plasma levels. The improved antioxidant activity of HDL, reflected by retardation in LDL oxidation, could contribute to limiting oxidative and inflammatory stress in advanced stages of TNBC.

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Solanum sessiliflorum is an Amazonian fruit (cubiu) that has been domesticated since pre-Colombian era. It is also used in folk medicine to treat some clinical conditions. This investigation chemically characterized and analyzed the in vitro antioxidant and antitumoral effect of a cubiu pulp/seed hydroalcoholic extract. Cubiu extract was chemically characterized by high-performance liquid chromatography with diode array detector (HPLC-DAD), its antioxidant capacity measured by 2.2-diphenyl-1-picrylhydrazyl (DPPH) assay, and the following complementary in vitro protocols were performed: (1) cytoprotective effect of cubiu on human peripheral blood mononuclear cells (PBMCs) exposed to H2O2, a genotoxic and procarcinogen molecule; (2) effect of cubiu on low density lipoproteins oxidation; and (3) cytotoxic and antiproliferative effect on breast (MCF-7) and colorectal (HT-29) cancer cell lines. Biochemical and flow cytometry analyses were conducted in these protocols. Cubiu extract presented high concentrations of caffeic and gallic acids, beta-carotene, catechin, quercetin, and rutin, and its antioxidant capacity was confirmed. Cubiu attenuated H2O2 cytotoxicity on PBMCs, presented lowering effect on LDL oxidation, and induced mortality and proliferative inhibition of colorectal cancer cells. In cancer cells, cubiu extract at 10 µg/mL showed similar effects to 5-fluorouracil chemo drug reducing its viability and frequency of S-phase, indicating that cells are undergoing mitosis. In summary, despite the limitations of in vitro protocols, our results suggest that cubiu has several biological properties that affect human health.

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Camu-camu (Myrciaria dubia) seeds are discarded without recovering the bioactive compounds. The main aim of the present work was to optimise the solvent mixture to extract higher total phenolic content and antioxidant capacity of camu-camu seeds. The optimised solvent system increased the extraction of phenolic compounds, in which vescalagin and castalagin were the main compounds. The optimised extract displayed antioxidant capacity measured by different chemical and biological assays, exerted antiproliferative and cytotoxic effects against A549 and HCT8 cancer cells, antimicrobial effects, protected human erythrocytes against hemolysis, inhibited α-amylase and α-glucosidase enzymes and presented in vitro antihypertensive effect. Additionally, the optimized extract inhibited human LDL copper-induced oxidation in vitro and reduced the TNF-α release and NF-κB activation in macrophages cell culture. Thus, the use of camu-camu seed showed to be a sustainable way to recover bioactive compounds with in vitro functional properties.

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Lipid nitration occurs during physiological and pathophysiological conditions, generating a variety of biomolecules capable to modulate inflammatory cell responses. Low-density lipoprotein (LDL) oxidation has been extensively related to atherosclerotic lesion development while oxidative modifications confer the particle pro-atherogenic features. Herein, we reviewed the oxidation versus nitration of human LDL protein and lipid fractions. We propose that unsaturated fatty acids present in LDL can be nitrated under mild nitration conditions, suggesting an anti-atherogenic role for LDL carrying nitro-fatty acids (NFA).

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Consumption of food products enriched with plant sterols and the use of ezetimibe reduce cholesterol absorption in the intestine and effectively reduce low-density lipoprotein (LDL) plasma levels. We evaluated the therapeutic effect of the ezetimibe+plant sterol association in patients with coronary artery disease still not reaching recommended lipid levels despite the use of statins. We performed a prospective open-label study with 41 patients with stable coronary disease and LDL >70 mg/dL. Patients were randomized into four groups for a 6-week treatment: the control (CT) group remained on the same statin therapy, the ezetimibe (EZ) group received 10 mg/day of ezetimibe, the plant sterol (PS) group received spread enriched with 2 g of plant sterols, and the ezetimibe+PS (EZ+PS) group received 10 mg/day EZ +2 g PS. Initial mean LDL level was 97.4 ± 31.1 mg/dL in control group, 105.1 ± 23.1 mg/dL in EZ group, 95.4 ± 27.7 mg/dL in PS group, and 97.0 ± 8.3 mg/dL in EZ+PS group (P > .05). After 6 weeks of treatment, LDL of patients slightly increased in the control group (+8.9%; P > .05) and dropped in EZ group (-19.1%; P = .06), PS group (-16.6%; P = .01), and EZ+PS group (-27.3%; P < .01). Mean LDL levels after treatment were 70.5 ± 17.9 mg/dL in EZ+PS group, lower than the other groups (control was 106.1 ± 34.9 mg/dL, EZ group was 85.0 ± 35.6 mg/dL, and PS was 79.6 ± 29.7 mg/dL) (P = .05 variance analysis factor [ANOVA]). Body weight, body-mass index, and glucose plasma levels did not change significantly after intervention. The combination of PS+ezetimibe was associated with lower LDL levels and suggests beneficial therapeutic effect against major cardiovascular events.

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Seis pulpas de frutas tropicales de origen colombiano: curuba (Passiflora tripartida var. Mollissima), gulupa (Passiflora edulis Sims), aguacate variedad Hass (Persea America Mill), lulo (Solanum quitoense Lam.), tomate de árbol (Cyphomandra betacea Sendt) y uchuva (Physalis peruvianaL) fueron empleadas para realizar el estudio del contenido total de fenoles, por el método de Folin Ciocalteu y la actividad antioxidante por los métodos químicos: DPPH (2,2-difenil-2-picrilhidrazilo) y FRAP (poder antioxidante para reducir iones férricos), y por los métodos biológicos: oxidación de lipoproteínas de baja densidad (LDL) e inhibición del estrés oxidativo sobre el crecimiento de Saccharomyces cerevisiae. Se encontró que el extracto de curuba presentó el mayor contenido total de fenoles con un valor de 683,48 ± 18,48 mg equivalentes de ácido gálico/100 g muestra B.H. (Base Húmeda). En cuanto a los ensayos de actividad antioxidante el extracto de aguacate presentó mayor actividad por el método DPPH con un valor de 165,10 ± 4,36 µmol Trolox/100 g muestra B.H., mientras que el extracto de curuba presentó la mayor actividad antioxidante por el método FRAP con un valor de 148,07 ± 12,07 µmol Trolox/g muestra B.H. En el ensayo de oxidación de LDL los extractos de curuba y uchuva presentaron la mayor capacidad de inhibición en la oxidación de dichas lipoproteínas con un valor de 1,61 ± 0,01 y 1,46 ± 0,06 nmol TMP (Tetrametoxipropano)/g muestra B.H., respectivamente. En el ensayo de inhibición del estrés oxidativo sobre el crecimiento de S. cerevisiae los extractos de aguacate, curuba y gulupa tuvieron el mayor efecto protector obteniéndose una concentración celular de.

Six pulp extracts of tropical fruits from Colombia: banana passion fruit (Passiflora tripartida var. Mollissima), gulupa (Passiflora edulis Sims), avocado (Persea americana Mill.), lulo (Solanum quitoense Lam.), tomate de árbol (Cyphomandra betacea Sendt.), and gooseberry (Physalis peruviana L.) were used for studying the total phenolic content by the Folin Ciocalteu method and the antioxidant activity by the chemical methods: DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric ion reducing antioxidant power), and by the biological methods: oxidation of low density lipoproteins (LDL) and inhibition of oxidative stress on Saccharomyces cerevissiae growth. It was found that banana passion fruit extract showed the highest content of total phenolics, with a value of 683.48 ± 18.48 mg equivalents to gallic acid/100 g fresh weight (F.W.). Regarding the antioxidant activity the avocado extract exhibited the highest activity in the DPPH assay, with a value of 165.10 ± 4.36 µmol Trolox/100g F.W. whereas the banana passion fruit extract showed the highest antioxidant activity by the FRAP method, with a value of 148.07 ± 12.07 µmol Trolox/g F.W. In the LDL oxidation assay the extracts from banana passion fruit and gooseberry presented the greater ability to inhibit the oxidation of those lipoproteins, with a value of 1.61 ± 0.01 and 1.46 ± 0.06 nmol TMP (Tetrametoxipropane)/g F.W., respectively. In the assay of inhibition of oxidative stress on S. cerevissiae the avocado, banana passion fruit, and gulupa extracts exhibited the main protective effect and the obtained values for cellular concentration were 1.96 ×10(7) cells/mL, 1.86 × 10(7) cells/mL, and 1.54 × 10(7) cells/mL, respectively, as compared to 0.99 × 10(7) cells/mL found.

Seis polpa de frutas tropicais da Colômbia: maracujá (Passiflora tripartite Mollissima var.), Gulupa (Passiflora edulis Sims), Hass abacate (Persea América Mill), lulo (Solanum quitoense Lam.), tomate de árvore (Cyphomandra betacea Sendt) e uchuva (Physalis Peruviana L) foram utilizados para o estudo do teor total de fenol pelo método de Folin-Ciocalteu e actividade antioxidante por métodos químicos: DPPH (2,2-difenil-2-picrilhidrazilo) e FRAP (poder antioxidante de reduzir iões férricos), e métodos biológicos: a oxidação de lipoproteínas de baixa densidade (LDL) e inibição de estresse oxidativo no crescimento de Saccharomyces cerevisiae. Os resultados são encontrados no extrato tiveram o maior teor total maracujá de fenóis com um valor de 683,48 ± 18,48 mg equivalentes o ácvido gálico/100 g amostra de ácido BH (Base úmida). Quanto à atividade antioxidante testes abacate extrato apresentou maior atividade com o método DPPH vale 165,10 ± 4,36 µmol Trolox / 100g de amostra BH, enquanto o extrato de maracujá apresentou a maior atividade antioxidante, método FRAP com um valor de 148,07 ± 12,07 µmol Trolox/g amostra BH. No ensaio de oxidação de LDL e extrai maracujá e uchuva teve a maior capacidade para inibir a oxidação de lipoproteínas estes com um valor de 1,61 ± 0,01 e 1,46 ± 0,06 nmol TMP (tetrametoxipropano)/g BH amostra, respectivamente. No ensaio de inibição de estresse oxidativo no crescimento de S. cerevisiae de extratos de abacate, maracujá e gulupa tinha o maior efeito protector sendo obtido uma concentração de células de 1,96 ×10(7) células/mL, 1,86 × 10(7) células/ml e 1,54 × 10(7) células/mL, respectivamente, em comparação com aqueles encontrados.

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The antioxidant effect of 5-Aminosalicylic acid (5-ASA) on copper-mediated LDL oxidation was followed either by the emitted chemiluminiscence (CL) or by UV-vis spectroscopy. 5-ASA addition extends the lag phase in a concentration-dependent manner without changes in the rate of the process in the autoaccelerated phase. The antioxidant behavior of 5-ASA was very similar to that of Trolox, a very efficient water soluble antioxidant. The copper-binding capacity of 5-ASA was evaluated by UV-visible spectroscopy. The addition of copper to a 5-ASA solution increases the absorbance at 332 nm and generates a new band at 298 nm. These changes in the UV-vis spectra indicate formation of a complex between 5-ASA and copper. However, LDL protection by 5-ASA is unrelated to its copper chelating capacity.

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