Hypertensive status and lipoprotein oxidation in an elderly population at high cardiovascular risk

Oxidative Stress Links Aging-Associated Cardiovascular Diseases and Prostatic Diseases

The incidence of chronic aging-associated diseases, especially cardiovascular and prostatic diseases, is increasing with the aging of society. Evidence indicates that cardiovascular diseases usually coexist with prostatic diseases or increase its risk, while the pathological mechanisms of these diseases are unknown. Oxidative stress plays an important role in the development of both cardiovascular and prostatic diseases. The levels of oxidative stress biomarkers are higher in patients with cardiovascular diseases, and these also contribute to the development of prostatic diseases, suggesting cardiovascular diseases may increase the risk of prostatic diseases via oxidative stress. This review summarizes the role of oxidative stress in cardiovascular and prostatic diseases and also focuses on the main shared pathways underlying these diseases, in order to provide potential prevention and treatment targets.

Anti-Atherosclerotic Activity of (3R)-5-Hydroxymellein from an Endophytic Fungus Neofusicoccum parvum JS-0968 Derived from Vitex rotundifolia through the Inhibition of Lipoproteins Oxidation and Foam Cell Formation

An endophytic fungus, Neofusicoccum parvum JS-0968, was isolated from a plant, Vitex rotundifolia. The chemical investigation of its cultures led to the isolation of a secondary metabolite, (3R)-5-hydroxymellein. It has been reported to have antifungal, antibacterial, and antioxidant activity, but there have been no previous reports on the effects of (3R)-5-hydroxymellein on atherosclerosis. The oxidation of lipoproteins and foam cell formation have been known to be significant in the development of atherosclerosis. Therefore, we investigated the inhibitory effects of (3R)-5-hydroxymellein on atherosclerosis through low-density lipoprotein (LDL) and high-density lipoprotein (HDL) oxidation and macrophage foam cell formation. LDL and HDL oxidation were determined by measuring the production of conjugated dienes and malondialdehyde, the amount of hyperchromicity and carbonyl content, conformational changes, and anti-LDL oxidation. In addition, the inhibition of foam cell formation was measured by Oil red O staining. As a result, (3R)-5-hydroxymellein suppressed the oxidation of LDL and HDL through the inhibition of lipid peroxidation, the decrease of negative charges, the reduction of hyperchromicity and carbonyl contents, and the prevention of apolipoprotein A-I (ApoA-I) aggregation and apoB-100 fragmentation. Furthermore, (3R)-5-hydroxymellein significantly reduced foam cell formation induced by oxidized LDL (oxLDL). Taken together, our data show that (3R)-5-hydroxymellein could be a potential preventive agent for atherosclerosis via obvious anti-LDL and HDL oxidation and the inhibition of foam cell formation.

Anti-Atherosclerotic Effects of Fruits of Vitex rotundifolia and Their Isolated Compounds via Inhibition of Human LDL and HDL Oxidation

Low-density lipoprotein (LDL) and high-density lipoprotein (HDL) oxidation are well known to increase the risk for atherosclerosis. In our ongoing research on natural products with inhibitory activities against oxidation of lipoproteins, fruits of Vitex rotundifolia were found to be highly active. There is no report on the effects on LDL and HDL oxidation. Herein, we investigated the inhibitory effects of V. rotundifolia fruit extract and its six compounds, which are: (1) artemetin, (2) casticin, (3) hesperidin, (4) luteolin, (5) vitexin, and (6) vanillic acid, against LDL and HDL oxidation. The LDL and HDL oxidations were determined by measuring production of conjugated dienes and thiobarbituric acid reactive substances, amount of hyperchromicity and carbonyl content, change in electrical charge, and apoA-I aggregation. In addition, the contents of the compounds in the extracts were analyzed using HPLC-DAD. Consequently, extracts of Vitex rotundifolia fruits and compounds 2 and 4 suppressed oxidation of LDL and HDL, showing inhibition of lipid peroxidation, decrease of negative charges in lipoproteins, reduction of hyperchromicity, decrease in carbonyl contents, and prevention of apoA-I aggregation. In particular, compounds 2 and 4 exhibited more potent inhibitory effect on oxidation of LDL and HDL than the extracts, suggesting their protective role against atherosclerosis via inhibition of LDL and HDL oxidation. The contents of artemetin, casticin, and vanillic acid in the extracts were 1.838 ± 0.007, 8.629 ± 0.078, and 1.717 ± 0.006 mg/g, respectively.

Benefits of the Mediterranean diet: Epidemiological and molecular aspects

More than 50 years after the Seven Countries Study, a large number of epidemiological studies have explored the relationship between the Mediterranean diet (MD) and health, through observational, case-control, some longitudinal and a few experimental studies. The overall results show strong evidence suggesting a protective effect of the MD mainly on the risk of cardiovascular disease (CVD) and certain types of cancer. The beneficial effects have been attributed to the types of food consumed, total dietary pattern, components in the food, cooking techniques, eating behaviors and lifestyle behaviors, among others. The aim of this article is to review and summarize the knowledge derived from the literature focusing on the benefits of the MD on health, including those that have been extensively investigated (CVD, cancer) along with more recent issues such as mental health, immunity, quality of life, etc. The review begins with a brief description of the MD and its components. Then we present a review of studies evaluating metabolic biomarkers and genotypes in relation to the MD. Other sections are dedicated to observation and intervention studies for various pathologies. Finally, some insights into the relationship between the MD and sustainability are explored. In conclusion, the research undertaken on metabolomics approaches has identified potential markers for certain MD components and patterns, but more investigation is needed to obtain valid measures. Further evaluation of gene-MD interactions are also required to better understand the mechanisms by which the MD diet exerts its beneficial effects on health. Observation and intervention studies, particularly PREDIMED, have provided invaluable data on the benefits of the MD for a wide range of chronic diseases. However further research is needed to explore the effects of other lifestyle components associated with Mediterranean populations, its environmental impact, as well as the MD extrapolation to non-Mediterranean contexts.

Angiotensin II receptor blockers induce autophagy in prostate cancer cells

Angiotensin II receptor blockers (ARBs) are anti-hypertensive drugs that competitively inhibit the binding of angiotensin II to its receptor, resulting in blood vessel dilation and the reduction of blood pressure. These antagonists are also known as sartans, and are a group of pharmaceuticals that possess tetrazole or imidazole groups. In the present study, the anticancer and antimetastatic effects of the ARBs fimasartan, losartan, eprosartan and valsartan on the human prostate cancer PC-3, DU-145 and LNCap-LN3 cell lines were investigated in vitro. The proliferation of the prostate cancer cells was inhibited following treatment with 100 µM ARB. In particular, treatment with fimasartan resulted in marked anti-proliferative activity compared with the other ARBs. With respect to the molecular mechanism of the growth inhibition exhibited by the ARBs, 3-methyladenin (3-MA), an autophagy inhibitor, was revealed to increase the survival rate of PC-3 cells when cell death inhibitors were pretreated with fimasartan. In addition, the ARBs induced autophagy with increased expression levels of autophagy protein (Atg) 5-12, Atg 16-like-1, beclin-1 and microtubule-associated protein 1A/1B-light chain 3 (LC3). Notably, the enhanced expression of LC3-II (a 6.7-fold increase at 72 h) was observed in PC3 cells treated with fimasartan. This was supported by the observation of the time-dependent accumulation of LC3-positive foci in PC-3. In addition, a migration assay indicated that the ARBs induced anti-metastatic effects in PC-3 and DU-145 cells. The aforementioned results suggest that ARBs may induce autophagy-associated cell death and anti-metastatic activity in prostate cancer cells. Thus, ARBs may be a potential medication for patients with prostate cancer and hypertension.

Mediterranean diets supplemented with virgin olive oil and nuts enhance plasmatic antioxidant capabilities and decrease xanthine oxidase activity in people with metabolic syndrome: The PREDIMED study

SCOPE

This study assessed plasmatic antioxidant capabilities and xanthine oxidase (XOX) activity in metabolic syndrome patients after 5 years intervention with Mediterranean diet (MeDiet) supplemented with extra-virgin olive oil or with nuts or with low-fat diet (the PREDIMED [PREvención con Dieta MEDiterránea] study).

METHODS AND RESULTS

Seventy-five participants were randomly selected. Daily energy and nutrient intake were assessed with a validated 137-item food frequency questionnaire, and adherence to the MeDiet was assessed using a 14-item questionnaire. Catalase, superoxide dismutase (SOD), myeloperoxidase, XOX activities and protein levels, and protein carbonyl derivatives, nitrotyrosine, nitrite and nitrate levels were determined in overnight fasting venous blood samples. The plasma activity and protein levels of SOD and catalase were significantly higher and XOX activity was lower in MeDiet supplemented with extra-virgin olive oil and MeDiet supplemented with nuts than in the control group. Participants in both MeDiet groups showed higher plasma nitrate levels than in the control group. Adherence to the MeDiet showed a positive correlation with SOD and catalase plasma antioxidant activities.

CONCLUSION

A MeDiet enriched with either virgin olive oil or nuts enhances the plasma antioxidant capabilities and decreases XOX activity in patients with the metabolic syndrome but we did not observe changes in myeloperoxidase or markers of oxidative damage.

Oxidative stress is associated with an increased antioxidant defense in elderly subjects: a multilevel approach

BACKGROUND

Studies of associations between plasma GSH-Px activity and cardiovascular risk factors have been done in humans, and contradictory results have been reported. The aim of our study was to assess the association between the scavenger antioxidant enzyme glutathione peroxidase (GSH-Px) activity in plasma and the presence of novel and classical cardiovascular risk factors in elderly patients.

METHODS

We performed a cross-sectional study with baseline data from a subsample of the PREDIMED (PREvención con DIeta MEDiterránea) study in Spain. Participants were 1,060 asymptomatic subjects at high risk for cardiovascular disease (CVD), aged 55 to 80, selected from 8 primary health care centers (PHCCs). We assessed classical CVD risk factors, plasma oxidized low-density lipoproteins (ox-LDL), and glutathione peroxidase (GSH-Px) using multilevel statistical procedures.

RESULTS

Mean GSH-Px value was 612 U/L (SE: 12 U/L), with variation between PHCCs ranging from 549 to 674 U/L (Variance =  013.5; P<0.001). Between-participants variability within a PHCC accounted for 89% of the total variation. Both glucose and oxidized LDL were positively associated with GSH-Px activity after adjustment for possible confounder variables (P = 0.03 and P = 0.01, respectively).

CONCLUSION

In a population at high cardiovascular risk, a positive linear association was observed between plasma GSH-Px activity and both glucose and ox-LDL levels. The high GSH-Px activity observed when an oxidative stress situation occurred, such as hyperglycemia and lipid oxidative damage, could be interpreted as a healthy defensive response against oxidative injury in our cardiovascular risk population.

The Mediterranean diet is associated with a reduction in premature mortality among middle-aged adults

The available large prospective studies supporting an inverse association between better adherence to the Mediterranean diet and lower mortality have mainly included older adults. It is not clear whether this inverse association is also present among younger individuals at lower mortality risk. Our aim was to assess the association between adherence to the Mediterranean diet and total mortality in middle-aged adults from the Seguimiento Universidad de Navarra (SUN) Project. We followed 15,535 Spanish university graduates for a mean of 6.8 y. Their mean age was 38 ± 12 y, 59.6% were females, and all were initially free of cardiovascular disease, cancer, and diabetes. A validated FFQ was used to assess dietary habits. Adherence to the Mediterranean diet was categorized into 3 groups according to the Mediterranean Diet Score (low, 0-2 points; moderate, 3-5 points; and high, 6-9 points). The outcome variable was total mortality. Cox proportional hazards models were used to estimate HR and 95% CI. We adjusted the estimates for sex, age, years of university education, BMI, smoking, physical activity, television watching, history of depression and baseline hypertension, and hypercholesterolemia. We observed 125 deaths during 105,980 person-years of follow-up. The fully adjusted HR for moderate and high adherence were 0.58 (95% CI: 0.34, 0.99; P = 0.05) and 0.38 (95% CI: 0.21, 0.70; P = 0.002), respectively. For each 2-point increment in the Mediterranean Diet Score, the HR of death was 0.72 (95% CI: 0.58, 0.91; P = 0.006). Among highly educated, middle-aged adults, adherence to the traditional Mediterranean diet was associated with reduced risk of death.

Total polyphenol excretion and blood pressure in subjects at high cardiovascular risk

BACKGROUND AND AIMS

Dietary factors are critical for the prevention and treatment of hypertension, but data on the effects of specific nutrients on blood pressure (BP) are scarce. The aim of this study was to assess the relationship between total polyphenol excretion (TPE) in urine, as an objective measurement of total polyphenol intake and BP in an elderly population at high cardiovascular risk.

METHODS AND RESULTS

Cross-sectional substudy of 589 high-risk participants entering in the PREDIMED trial. BP was measured and TPE was determined in urine by Folin-Ciocalteu assay. A significant positive association was observed between TPE in urine and daily intake of fruit and vegetables (F&V), coffee or wine after adjusting for potential confounders. The intake of 100 g of F&V (Beta=0.150;P<0.001) had a greater contribution to TPE than 100 mL of coffee (Beta=0.141;P=0.001), and the latter two foods contributed more than the consumption of 100 mL of wine (Beta=0.120;P=0.019). An inverse association was observed between urinary TPE and the prevalence of hypertension. Participants in the highest quartile of urinary TPE had a reduced prevalence of hypertension compared to those in the lowest quartile (Odds Ratio=0.64; 95% confidence interval 0.45 to 0.92; P=0.015). Systolic and diastolic BP were inversely associated with urinary TPE after adjustment for potential confounders (P=0.024 and P=0.003, respectively).

CONCLUSIONS

Polyphenol intake, assessed via TPE in urine, was negatively associated with BP levels and prevalence of hypertension in an elderly Mediterranean population at high cardiovascular risk. Participants with the highest intake of polyphenol-rich foods showed the lowest BP measurements.

Soluble fibre (Plantago ovata husk) reduces plasma low-density lipoprotein (LDL) cholesterol, triglycerides, insulin, oxidised LDL and systolic blood pressure in hypercholesterolaemic patients: A randomised trial

The objective was to evaluate whether the soluble fibre Plantago ovata (Po)-husk improves cardiovascular disease (CVD) risk biomarkers including low-density lipoprotein cholesterol (LDL-C).

METHODS

In a multi-centred, double-blind, placebo-controlled, parallel, randomised trial conducted in primary care-clinics in Spain, France and Holland, mild-moderate hypercholesterolaemic patients (age range: 43-67 years) received 14 g/d of Po-husk (n=126) or placebo (microcrystalline-cellulose 14 g/d; n=128) in a low saturated fat diet for 8 weeks. Subsequently, if LDL-C remained > or = 3.35 mmol/L [130 mg/dL], participants proceeded with the fibre plus simvastatin (20mg/d) for further 8 weeks. Lipid profile, blood pressure (BP), insulin, oxidised LDL and some gene polymorphisms involved in CVD risk were measured.

RESULTS

Relative to placebo, Po-husk reduced plasma LDL-C by -6% (P<0.0002), total cholesterol (TC) by -6%, triglycerides (TG) by -21.6%, apolipoprotein (Apo) B-100 by -6.7%, oxidised LDL by a mean of -6.82 U/L (95%CI: 3.15-10.48), insulin by -4.68 pmol/L (95%CI: 0.68-8.67) and systolic BP by -4.0mm Hg (95%CI; 1.2-6.7) (P<0.05). The TG-lowering effect in the Po-husk group was magnified by variants in plasminogen-activator-inhibitor (PAI-1; rs1799768) and fatty acid-binding protein (FABP-2; rs1799883) genes. At 16 weeks, the intra-group action of simvastatin (20mg/d) added to Po-husk or placebo was a similar LDL-C reduction.

CONCLUSIONS

Po-husk, apart from lowering LDL-C, also reduced TG, TG related to certain gene variants, TC, Apo B-100, oxLDL, insulin-resistance and systolic BP in mild-moderate hypercholesterolaemic individuals. Thus, the target patients to receive Po-husk would be those who present a cluster of various CVD risk factors, such as metabolic syndrome.