Antiatherogenic components of olive oil

Mediterranean diet in the targeted prevention and personalized treatment of chronic diseases: evidence, potential mechanisms, and prospects

The prevalence of chronic diseases is currently a major public health issue worldwide and is exploding with the population growth and aging. Dietary patterns are well known to play a important role in our overall health and well-being, and therefore, poor diet and malnutrition are among the most critical risk factors for chronic disease. Thus, dietary recommendation and nutritional supplementation have significant clinical implications for the targeted treatment of some of these diseases. Multiple dietary patterns have been proposed to prevent chronic disease incidence, like Dietary Approaches to Stop Hypertension (DASH) and Diabetes Risk Reduction Diet (DRRD). Among them, the MedDiet, which is one of the most well-known and studied dietary patterns in the world, has been related to a wide extent of health benefits. Substantial evidence has supported an important reverse association between higher compliance to MedDiet and the risk of chronic disease. Innovative strategies within the healthcare framework of predictive, preventive, and personalized medicine (PPPM/3PM) view personalized dietary customization as a predictive medical approach, cost-effective preventive measures, and the optimal dietary treatment tailored to the characteristics of patients with chronic diseases in primary and secondary care. Through a comprehensive collection and review of available evidence, this review summarizes health benefits of MedDiet in the context of PPPM/3PM for chronic diseases, including cardiovascular disease, hypertension, type 2 diabetes, obesity, metabolic syndrome, osteoporosis, and cancer, thereby a working hypothesis that MedDiet can personalize the prevention and treatment of chronic diseases was derived.

Ultrasound assisted extraction and liposome encapsulation of olive leaves and orange peels: How to transform biomass waste into valuable resources with antimicrobial activity

Every year million tons of by-products and waste from olive and orange processing are produced by agri-food industries, thus triggering environmental and economic problems worldwide. From the perspective of a circular economy model, olive leaves and orange peels can be valorized in valuable products due to the presence of bioactive compounds such as polyphenols exhibiting beneficial effects on human health. The aqueous extracts of olive leaves and orange peels rich in phenolic compounds were prepared by ultrasound-assisted extraction. Both extracts were characterized in terms of yield of extraction, total phenolic content and antioxidant capacity; the polyphenolic profiles were deeper investigated by HPLC-MS analysis. Each extract was included in liposomes composed by a natural phospholipid, 1,2-dioleoyl-sn-glycero-3-phosphocholine,and cholesterol prepared according to the thin-layer evaporation method coupled with a sonication process. The antimicrobial activity of the extracts, free and loaded in liposomes, was investigated according to the broth macrodilution method against different strains of potential bacterial pathogenic species: Staphylococcus aureus (NCIMB 9518), Bacillus subtilis (ATCC 6051) and Enterococcus faecalis (NCIMB 775) as Gram-positive, while Escherichia coli (NCIMB 13302), Pseudomonas aeruginosa (NCIMB 9904) and Klebsiella oxytoca (NCIMB 12259) as Gram-negative. The encapsulation of olive leaves extract in liposomes enhanced its antibacterial activity against S. aureus by an order of magnitude.

Effect of Geographical Location on the Phenolic and Mineral Composition of Chetoui Olive Leaves

In this study, we investigated the influence of pedological parameters and variation of altitude on the mineral nutrients, phenolic compounds, and antioxidant activities of olive leaves. Samples of the Chetoui cultivar were collected from eight geographical locations with different altitudes. Levels of phenolic compounds varied according to the altitude. Classification of the locations revealed that altitude 1 (>500 m) was characterized by high levels of secoiridoids and simple phenols, while altitude 2 (500-300 m) and altitude 3 (<300 m) were higher in flavonoids. Levels of Mn, Ca and B in the leaves and level of Zn in the soil were significantly correlated with the abundance of oleuropein and luteolin-7-O glucoside, the most important phenols in Chetoui olive leaves. The results suggest that, in addition to pedological criteria, environmental conditions also influence the formation of phenolic compounds.

Effect of macronutrient fertilization on olive oil composition and quality under irrigated, intensive cultivation management

BACKGROUND

Intensive olive (Olea europaea L.) orchards are fertilized, mostly with the macronutrients nitrogen (N), phosphorus (P) and potassium (K). The effects of different application levels of these nutrients on olive oil composition and quality were studied over 6 years in a commercial intensively cultivated 'Barnea' olive orchard in Israel.

RESULTS

Oil quality and composition were affected by N, but not P or K availability. Elevated N levels increased free fatty acid content and reduced polyphenol level in the oil. Peroxide value was not affected by N, P or K levels. The relative concentrations of palmitoleic, linoleic and linolenic fatty acids increased with increasing levels of N application, whereas that of oleic acid, monounsaturated-to-polyunsaturated fatty acid ratio and oleic-to-linoleic ratio decreased.

CONCLUSION

These results indicate that intensive olive orchard fertilization should be carried out carefully, especially where N application is concerned, to avoid a decrease in oil quality due to over-fertilization. Informed application of macronutrients requires leaf and fruit analyses to establish good agricultural practices, especially in view of the expansion of olive cultivation to new agricultural regions and soils. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Olive oil protects against progression of heart failure by inhibiting remodeling of heart subsequent to myocardial infarction in rats

We examined the beneficial effects of olive oil against heart failure post-myocardial infarction (PMI), induced by coronary artery ligation in rats. Animals were divided into sham and ligated groups and fed either regular chow, olive oil (10% wt/wt), or corn oil (10% wt/wt) and were followed up to 16 weeks. On the echocardiography at 3 days (PMI), in the ligated regular chow (LRC), ligated olive oil (LOO), and ligated corn oil (LCO) left ventricular ejection fraction (LVEF) decrease was 12.14%, 16.42%, and 17.53% from the baseline, respectively. However, only LOO group improved LVEF significantly at 16 weeks PMI and became comparable with all sham groups. Both scar formation and collagen deposition at 16 weeks PMI were less pronounced in the LOO group. Myocardial TNF-α level at 4 weeks of PMI increased by 176%, 11%, and 181% in the LRC, LOO, and LCO groups, respectively. Plasma TNF-α levels in LOO were significantly lower than LRC group after 4 weeks of PMI. Myocardial redox ratio (reduced glutathione/oxidized glutathione) decreased at 4 weeks PMI by 44.4%, 16.4%, and 36.9% in the LRC, LOO, and LCO groups, respectively, compared to the baseline. These changes in the redox ratio at 16 weeks PMI were further exacerbated in the LRC and LCO groups. Lipid hydroperoxides formation increased at 4 weeks PMI by 137.4%, 14.6%, and 97.1% in the LRC, LOO, and LCO groups, respectively. Since coronary artery ligation decreased left ventricular ejection fraction, increased myocardial TNF-α and oxidative stress, and since olive oil was able to inhibit these effects, it is proposed that dietary olive oil modulates cardiac remodeling and heart failure subsequent to myocardial infarction.

Effect of Supplementation with Olive Leaf Extract Enriched with Oleuropein on the Metabolome and Redox Status of Athletes’ Blood and Urine—A Metabolomic Approach

Oleuropein (OE) is a secoiridoid glycoside occurring mostly in the Oleaceae family and presenting several pharmacological properties, including hypolipidemic and antioxidant properties. Based on these, several dietary supplements containing olive leaf extracts enriched with OE are commercially available in many countries. The current study aimed to examine the effect of supplementation with such an extract on the serum and urine metabolome of young healthy male athletes. For this purpose, applying a randomized, balanced, double-blind study, nine young, healthy males (physical education students) received either a commercially prepared extract or placebo for one week, followed by a two-week washout period; then, they were subsequently dosed with the alternate scheme (crossover design). Urine and serum samples were analyzed using UHPLC-HRMS, followed by evaluation with several multivariate methods of data analysis. The data were interpreted using a multilevel metabolomic approach (multilevel-sPLSDA) as it was found to be the most efficient approach for the study design. Metabolic pathway analysis of the most affected metabolites revealed that tryptophan and acylcarnitine’s biochemistries were most influenced. Furthermore, several metabolites connected to indole metabolism were detected, which may indicate enhanced serotonin turnover. Phenylethylamine and related metabolites, as well as estrone, were connected to enhanced performance. In addition, possible changes to the lipidemic profile and the blood and urine redox statuses were investigated.

Oleuropein Aglycone Peracetylated (3,4-DHPEA-EA(P)) Attenuates H2O2-Mediated Cytotoxicity in C2C12 Myocytes via Inactivation of p-JNK/p-c-Jun Signaling Pathway

Oleuropein, a glycosylated secoiridoid present in olive leaves, is known to be an important antioxidant phenolic compound. We studied the antioxidant effect of low doses of oleuropein aglycone (3,4-DHPEA-EA) and oleuropein aglycone peracetylated (3,4-DHPEA-EA(P)) in murine C2C12 myocytes treated with hydrogen peroxide (H2O2). Both compounds were used at a concentration of 10 μM and were able to inhibit cell death induced by the H2O2 treatment, with 3,4-DHPEA-EA(P) being more. Under our experimental conditions, H2O2 efficiently induced the phosphorylated-active form of JNK and of its downstream target c-Jun. We demonstrated, by Western blot analysis, that 3,4-DHPEA-EA(P) was efficient in inhibiting the phospho-active form of JNK. This data suggests that the growth arrest and cell death of C2C12 proceeds via the JNK/c-Jun pathway. Moreover, we demonstrated that 3,4-DHPEA-EA(P) affects the myogenesis of C2C12 cells; because MyoD mRNA levels and the differentiation process are restored with 3,4-DHPEA-EA(P) after treatment. Overall, the results indicate that 3,4-DHPEA-EA(P) prevents ROS-mediated degenerative process by functioning as an efficient antioxidant.

Metabolic and Vascular Effect of the Mediterranean Diet

Several studies indicated how dietary patterns that were obtained from nutritional cluster analysis can predict disease risk or mortality. Low-grade chronic inflammation represents a background pathogenetic mechanism linking metabolic risk factors to increased risk of chronic degenerative diseases. A Mediterranean diet (MeDi) style has been reported as associated with a lower degree of inflammation biomarkers and with a protective role on cardiovascular and cerebrovascular events. There is heterogeneity in defining the MedDiet, and it can, owing to its complexity, be considered as an exposome with thousands of nutrients and phytochemicals. Recently, it has been reported a novel positive association between baseline plasma ceramide concentrations and cardiovascular events and how adherence to a Mediterranean Diet-style may influence the potential negative relationship between elevated plasma ceramide concentrations and cardiovascular diseases (CVD). Several randomized controlled trials (RCTs) showed the positive effects of the MeDi diet style on several cardiovascular risk factors, such as body mass index, waist circumference, blood lipids, blood pressure, inflammatory markers and adhesion molecules, and diabetes and how these advantages of the MeDi are maintained in comparison of a low-fat diet. Some studies reported a positive effect of adherence to a Mediterranean Diet and heart failure incidence, whereas some recent studies, such as the PREDIMED study, showed that the incidence of major cardiovascular events was lower among those assigned to MeDi supplemented with extra-virgin olive oil or nuts than among those assigned to a reduced-fat diet. New studies are needed to better understand the molecular mechanisms, whereby the MedDiet may exercise its effects. Here, we present recent advances in understanding the molecular basis of MedDiet effects, mainly focusing on cardiovascular diseases, but also discussing other related diseases. We review MedDiet composition and assessment as well as the latest advances in the genomic, epigenomic (DNA methylation, histone modifications, microRNAs, and other emerging regulators), transcriptomic (selected genes and whole transcriptome), and metabolomic and metagenomic aspects of the MedDiet effects (as a whole and for its most typical food components). We also present a review of the clinical effects of this dietary style underlying the biochemical and molecular effects of the Mediterranean diet. Our purpose is to review the main features of the Mediterranean diet in particular its benefits on human health, underling the anti-inflammatory, anti-oxidant and anti-atherosclerotic effects to which new knowledge about epigenetic and gut-microbiota relationship is recently added.

Identification of putative genes for polyphenol biosynthesis in olive fruits and leaves using full-length transcriptome sequencing

Olive (Olea europaea) is a rich source of valuable bioactive polyphenols, which has attracted widespread interest. In this study, we combined targeted metabolome, Pacbio ISOseq transcriptome, and Illumina RNA-seq transcriptome to investigate the association between polyphenols and gene expression in the developing olive fruits and leaves. A total of 12 main polyphenols were measured, and 122 transcripts of 17 gene families, 101 transcripts of 9 gene families, and 106 transcripts of 6 gene families that encode for enzymes involved in flavonoid, oleuropein, and hydroxytyrosol biosynthesis were separately identified. Additionally, 232 alternative splicing events of 18 genes related to polyphenol synthesis were analyzed. This is the first time that the third generations of full-length transcriptome technology were used to study the gene expression pattern of olive fruits and leaves. The results of transcriptome combined with targeted metabolome can help us better understand the polyphenol biosynthesis pathways in the olive.

Prevention of rocuronium induced mast cell activation with prophylactic oleuropein rich diet in anesthetized rabbits1

PURPOSE

The effect of a prophylactic oleuropein-rich diet before anesthesia accompanied by the widely-used steroid-based neuromuscular drug rocuronium on mast cell activation was investigated in the study.

METHODS

14 rabbits used in the study. The rabbits in the oleuropein group were given oleuropein-rich extract added to the animals' water at doses of 20 mg/kg oleuropein for 15 days orally. After 15 days, all rabbits in the two groups were given general anesthesia with rocuronium of 1 mg/kg. After 1 day, animals were sacrificed and the liver tissue sections stained with H&E, toluidine blue and tryptase for immunohistochemical study.

RESULTS

There was no statistically significant difference between ALT, AST and albumin averages of the oleuropein and control groups (p> 0.05). The tryptase average of the control group was higher than the tryptase average of the oleuropein group and this difference was statistically significant (p=0.003). The T. blue average in the oleuropein group was higher than the control group. However, there was no statistically significant difference between groups (p=0.482).

CONCLUSIONS

Rocuronium adverse effects, like hypersensitivity and anaphylaxis, may limit routine use of this substance. The use of oleuropein reduced the number of inflammatory cells and prevented degranulation.

The Dietary Approaches to Stop Hypertension (DASH)-Style Diet and an Alternative Mediterranean Diet are Differently Associated with Serum Inflammatory Markers in Female Adults

Background:

Studies on the association between a priori dietary patterns and serum highly sensitive C-reactive protein (hs-CRP) have led to inconsistent results, and we are not aware of any study on interleukin 17A (IL-17A) as an inflammatory marker associated with autoimmune diseases.

Objective:

The present study aimed to investigate the association between Dietary Approaches to Stop Hypertension (DASH) and the Mediterranean dietary patterns with circulating hs-CRP and IL-17A levels.

Methods:

In this cross-sectional study, female teachers (aged 20-50 years) who lived in Yazd, Iran, were randomly selected from elementary, guidance, and high schools from September 2015 to February 2016. Anthropometric data, as well as general information and dietary food intakes, were gathered, and each participant gave 1 blood sample. Participants were categorized into tertiles based on the DASH and the Mediterranean diet calculated scores. The associations between the dietary patterns and serum hs-CRP and IL-17A levels were assessed in the crude and multivariable models. In total, 320 female teachers aged 40.38 (8.08) years were included.

Results:

The DASH diet was associated with lower serum hs-CRP levels in the crude ( P = .05) and the fully adjusted models ( P = .02), while it was not significantly associated with IL-17A levels. The participants with the highest adherence to the Mediterranean diet had significantly lower circulating IL-17A levels ( P = .04) even controlling for all confounders ( P = .02); however, there was not a significant relationship between this diet and hs-CRP levels.

Conclusions:

The DASH and the Mediterranean dietary patterns might be differently associated with inflammatory markers. Further prospective studies are recommended to confirm our results.

Synthesis and antioxidant evaluation of lipophilic oleuropein aglycone derivatives

Oleuropein is the most important phenolic compound present in olive cultivars, but it is scarcely present in extra virgin olive oil (EVOO) due to its high hydrophilicity and degradability. Thus, a set of oleuropein aglycone derivatives were synthesized by transacetylation under mild conditions with the aim of circumventing these drawbacks and making the active moiety in oleuropein suitable to be added to food fats. The oleuropein aglycone (closed ring form) is obtained by hydrolyzing oleuropein using Lewis acid catalysis. Then, the permeation profiles as well as the antioxidant capacity of the oleuropein aglycone derivatives were evaluated by ORAC, DPPH assays and by ROS formation using the SH-SY5Y cell line. The biological activities of the obtained compounds exhibited a dependence on their level of lipophilicity.

Coriander (Coriandrum sativum): A promising functional food toward the well-being

Coriandrum sativum (C. sativum) or coriander is one of the most popularly used spices in culinary worldwide, and its medicinal values has been recognized since ancient time. C. sativum contains bioactive phytochemicals that are accounted for a wide range of biological activities including antioxidant, anticancer, neuroprotective, anxiolytic, anticonvulsant, analgesic, migraine-relieving, hypolipidemic, hypoglycemic, hypotensive, antimicrobial, and antiinflammatory activities. The major compound, linalool, abundantly found in seeds is remarked for its abilities to modulate many key pathogenesis pathways of diseases. Apart from the modulating effects, the potent antioxidant property of the C. sativum provides a key mechanism behind its protective effects against neurodegenerative diseases, cancer, and metabolic syndrome. This review shed light on comprehensive aspects regarding the therapeutic values of the C. sativum, which indicate its significance of being a promising functional food for promoting the well-being in the era of aging and lifestyle-related diseases.

Impact of a Proprietary Standardized Olive Fruit Extract (SOFE) on Cardio-Ankle Vascular Index, Visual Analog Scale and C-Reactive Protein Assessments in Subjects with Arterial Stiffness Risk

INTRODUCTION

The chemical components of olive fruit provide a wide range of cardiovascular benefits. Arterial stiffness is an important cardiovascular risk factor and can be assessed using the Cardio-Ankle Vascular Index (CAVI).

OBJECTIVE

The objective of this study was to assess the impact of a proprietary standardized olive fruit extract (SOFE) in subjects at risk for arterial stiffness.

METHODS

Twelve of 36 subjects were assigned to each of the following groups for this 11-day, double-blind, placebo-controlled study: Group 1: 250 mg SOFE-50 mg active ingredient, hydroxytyrosol (dosage achieved with two capsules per day); Group 2: 500 mg SOFE-100 mg active ingredient, hydroxytyrosol (dosage achieved with two capsules per day); and Group 3: placebo.

RESULTS

All three groups showed a decrease in CAVI scores, although no significant between-group differences were observed. Group 2 had the largest reduction, with mean CAVI scores decreasing from 11.02 to 8.91. Group 2 showed the strongest response in visual analog scale (VAS) energy intensity (11.71% increase). Results for C-reactive protein (CRP) blood levels showed no changes of statistical significance between groups. Mean triglyceride levels from Group 2 decreased by 21.64%, the most significant change among all three groups.

CONCLUSIONS

SOFE, an olive fruit extract containing many of the phytochemicals shown to provide cardiovascular benefits, was safe and well-tolerated. SOFE 500 mg had a greater effect on CAVI scores, suggesting improved arterial elasticity, and a clear reduction in triglycerides compared with placebo and SOFE 250 mg. The decreased CAVI scores suggest that increasing high-density lipoprotein cholesterol and lowering triglycerides with SOFE could potentially reduce patients' risk of developing atherosclerosis. Although more studies are needed, positive cardiovascular health trends, including improved vessel elasticity and positive triglyceride effects, were evident with SOFE.

Prevention of intraocular pressure elevation with oleuropein rich diet in rabbits, during the general anaesthesia

Background

Oleuropein is known to have anti-oxidant and anti-inflammatory effects. An important aim of anesthetic management in ocular surgery is to keep the intraocular pressure under control. Studies have researched a variety of prophylactic materials used to prevent increases in intraocular pressure. We aimed to research the effects of oleuropein on intraocular pressure (IOP) during general anaesthesia.

Methods

Fourteen New Zealand rabbits were randomly divided into two groups of seven. The rabbits in Group O were given olive leaf extract (OLE) equivalent to a daily dose of 20 mg/kg oleuropein for 15 days. HPLC method used for oleuropein standardization. For anaesthesia induction 1 mg/kg rocuronium was given and after muscle relaxation all animals had a V-gel Rabbit inserted. Anesthetic maintenance was provided by 1 MAC isoflurane. Twenty minutes after rabbits were given 10 mg/kg ketamine, basal IOP values were measured. After the V-gel rabbit was inserted, in the 5th, 10th, 20th, 25th and 30th minutes measurements were repeated.

Results

IOP data variation of OLE group was compared with control group and the measured levels were lower in Group O during the anaesthesia. IOP was 33.8 ± 4 mmHg in Group C and 24.1 ± 8 mmHg in Group O in 25th minute and the difference between the two groups was statistically significant at this time.

Conclusion

We observed that consumption of prophylactic OLE had a reducing effect on IOP in the period before waking in anaesthesia. We believe it is necessary to investigate the effects of OLE on IOP in broad participation patient groups.

Computer-aided discovery of biological activity spectra for anti-aging and anti-cancer olive oil oleuropeins

Aging is associated with common conditions, including cancer, diabetes, cardiovascular disease, and Alzheimer's disease. The type of multi-targeted pharmacological approach necessary to address a complex multifaceteddisease such as aging might take advantage of pleiotropic natural polyphenols affecting a wide variety of biological processes. We have recently postulated that the secoiridoids oleuropein aglycone (OA) and decarboxymethyl oleuropein aglycone (DOA), two complex polyphenols present in health-promoting extra virgin olive oil (EVOO), might constitute anew family of plant-produced gerosuppressant agents. This paper describes an analysis of the biological activity spectra (BAS) of OA and DOA using PASS (Prediction of Activity Spectra for Substances) software. PASS can predict thousands of biological activities, as the BAS of a compound is an intrinsic property that is largely dependent on the compound's structure and reflects pharmacological effects, physiological and biochemical mechanisms of action, and specific toxicities. Using Pharmaexpert, a tool that analyzes the PASS-predicted BAS of substances based on thousands of “mechanism-effect” and “effect-mechanism” relationships, we illuminate hypothesis-generating pharmacological effects, mechanisms of action, and targets that might underlie the anti-aging/anti-cancer activities of the gerosuppressant EVOO oleuropeins.

Effects of a long-term lifestyle intervention program with Mediterranean diet and exercise for the management of patients with metabolic syndrome in a primary care setting

BACKGROUND

The impact of a lifestyle intervention (LSI) program for the long-term management of subjects with metabolic syndrome in a primary care setting is not known.

METHODS

This 3-year prospective controlled trial randomized adult subjects with metabolic syndrome to receive intensive LSI or to usual care in a community health centre in Malaga, Spain. LSI subjects received instruction on Mediterranean diet and a regular aerobic exercise program by their primary care professionals. Primary outcome included changes from baseline on different components of metabolic syndrome (abdominal circumference, blood pressure, HDL-cholesterol, fasting plasma glucose and triglycerides).

RESULTS

Among the 2,492 subjects screened, 601 subjects with metabolic syndrome (24.1%) were randomized to LSI (n = 298) or to usual care (n = 303); of them, a 77% and a 58%, respectively, completed the study. At the end of the study period, LSI resulted in significant differences vs. usual care in abdominal circumference (-0.4 ± 6 cm vs. + 2.1 ± 6.7 cm, p < 0.001), systolic blood pressure (-5.5 ± 15 mmHg vs. -0.6 ± 19 mmHg, p = 0.004), diastolic blood pressure (-4.6 ± 10 mmHg vs. -0.2 ± 13 mmHg, p < 0.001) and HDL-cholesterol (+4 ± 12 mg/dL vs. + 2 ± 12 mg/dL, p = 0.05); however, there were no differences in fasting plasma glucose and triglyceride concentration (-4 ± 35 mg/dl vs. -1 ± 32 mg/dl, p = 0.43 and -0.4 ± 83 mg/dl vs. +6 ± 113 mg/dl, p = 0.28).

CONCLUSION

Intensive LSI counseling provided by primary care professionals resulted in significant improvements in abdominal circumference, blood pressure and HDL-cholesterol but had limited effects on glucose and triglyceride levels in patients with metabolic syndrome.

The Mediterranean-style dietary pattern and mortality among men and women with cardiovascular disease

BACKGROUND

The role of the Mediterranean diet among individuals with previous cardiovascular disease (CVD) is uncertain.

OBJECTIVE

The aim of this study was to assess the association between the Alternate Mediterranean Diet (aMED) score and all-cause, cardiovascular, and cancer mortality in men and women with CVD from the Health Professionals Follow-Up Study and the Nurses' Health Study.

DESIGN

This study included 6137 men and 11,278 women with myocardial infarction, stroke, angina pectoris, coronary bypass, and coronary angioplasty. Diet was first assessed in 1986 for men and in 1980 for women with a food-frequency questionnaire (FFQ) and then repeatedly every 2-4 y. Cumulative consumption was calculated with all available FFQs from the diagnosis of CVD to the end of the follow-up in 2008.

RESULTS

During a median follow-up of 7.7 y (IQR: 4.2-11.8) for men and 5.8 y (IQR: 3.8-8.0) for women, we documented 1982 deaths (1142 from CVD and 344 from cancer) among men and 1468 deaths (666 from CVD and 197 from cancer) among women. In multivariable Cox regression models, the pooled RR of all-cause mortality from a comparison of the top with the bottom quintiles of the aMED score was 0.81 (95% CI: 0.72, 0.91; P-trend < 0.001). The corresponding pooled RR for CVD mortality was 0.85 (95% CI: 0.67, 1.09; P-trend = 0.30), for cancer mortality was 0.85 (95% CI: 0.65, 1.11; P-trend = 0.10), and for other causes was 0.79 (95% CI: 0.65, 0.97; P-trend = 0.01). A 2-point increase in adherence to the aMED score was associated with a 7% (95% CI: 3%, 11%) reduction in the risk of total mortality.

CONCLUSION

Adherence to a Mediterranean-style dietary pattern was associated with lower all-cause mortality in individuals with CVD.

Development and validation of a combined methodology for assessing the total quality control of herbal medicinal products--application to oleuropein preparations

Oleuropein (OE) is a secoiridoid glycoside, which occurs mostly in the Oleaceae family presenting several pharmacological properties, including antioxidant, cardio-protective, anti-atherogenic effects etc. Based on these findings OE is commercially available, as Herbal Medicinal Product (HMP), claimed for its antioxidant effects. As there are general provisions of the medicine regulating bodies e.g. European Medicines Agency, the quality of the HMP’s must always be demonstrated. Therefore, a novel LC-MS methodology was developed and validated for the simultaneous quantification of OE and its main degradation product, hydroxytyrosol (HT), for the relevant OE claimed HMP’s. The internal standard (IS) methodology was employed and separation of OE, HT and IS was achieved on a C18 Fused Core column with 3.1 min overall run time employing the SIM method for the analytical signal acquisition. The method was validated according to the International Conference on Harmonisation requirements and the results show adequate linearity (r² > 0.99) over a wide concentration range [0.1–15 μg/mL (n=12)] and a LLOQ value of 0.1 μg/mL, for both OE and HT. Furthermore, as it would be beneficial to control the quality taking into account all the substances of the OE claimed HMP’s; a metabolomics-like approach has been developed and applied for the total quality control of the different preparations employing UHPLC-HRMS-multivariate analysis (MVA). Four OE-claimed commercial HMP’s have been randomly selected and MVA similarity-based measurements were performed. The results showed that the examined samples could also be differentiated as evidenced according to their scores plot. Batch to batch reproducibility between the samples of the same brand has also been determined and found to be acceptable. Overall, the developed combined methodology has been found to be an efficient tool for the monitoring of the HMP’s total quality. Only one OE HMP has been found to be consistent to its label claim.

Oleic acid increases hepatic sex hormone binding globulin production in men

SCOPE

Low circulating sex hormone-binding globulin (SHBG) is an independent risk factor for cardiovascular disease. Mediterranean diet has been associated with a decreased risk of cardiovascular disease. We aimed to test the hypothesis that the increase of circulating MUFA associated with olive oil consumption (primary fat source in Mediterranean diet) increases SHBG serum levels.

METHODS AND RESULTS

A total of 315 men were included. In these patients, nutrition data and plasma samples for SHBG assessment were obtained. In vitro studies to examine the effects of oleic and linoleic acid on SHBG production using HepG2 cells were performed. We provided evidence that SHBG serum levels were significantly higher in subjects using olive oil for cooking in comparison with subjects using sunflower oil. The SHBG levels correlated positively with MUFA (p < 0.001) and negatively with saturated fatty acids (p = 0.003). In the multiple regression analysis, MUFA were independently associated with SHBG levels and accounted for the 20.4% of SHBG variance. In vitro studies revealed that oleoyl-CoA increases SHBG production by downregulating PPAR-γ levels in HepG2 cells.

CONCLUSION

Olive oil consumption is associated with elevated SHBG serum levels. PPAR-γ downregulation induced by oleoyl-CoA is an important underlying mechanism of such regulation.

Oleuropein and oleacein may restore biological functions of endothelial progenitor cells impaired by angiotensin II via activation of Nrf2/heme oxygenase-1 pathway

Endothelial progenitor cells (EPCs) are responsible for neovascularization of ischaemic tissue and may participate in re-endothelization of an injured arterial wall. There is evidence that angiotensin II, by an increase of gp91phox expression and induction of ROS generation, accelerates cell senescence and impairs functions of EPCs. Oleacein is a main phenolic compound from olive oil, whereas oleuropein is present in olive leaves. Both compounds possess antioxidative, hypotensive and anti-inflammatory properties and show beneficial activity on the cardiovascular system. In this study, we examined whether oleoeuropein and oleacein could protect EPCs against impairment of their functions due to angiotensin-induced cell senescence. CD31(+)/VEGFR-2(+) cells were isolated from young healthy volunteers blood samples and cultured on fibronectin-coated plates with angiotensin (1.0μM) in presence or absence of increasing concentrations (from 1.0 to 10.0 μM) of oleoeuropein or oleacein. As compared to angiotensin II-treated cells, EPCs exposed to oleacein or oleuropein prior to angiotensin II showed a significant increase of proliferation and telomerase activity, and a decrease in the percentage of senescent cells and intracellular ROS formation. Oleacein and oleuropein restored migration, adhesion and tube formation of EPCs diminished by angiotensin II in a concentration-dependent manner. This effect was related to NF-E2-related factor 2 (Nrf2) transcription factor activation and the increase of heme oxygenase-1 (HO-1) expression.

The biotransformation of oleuropein in rats

A highly sensitive and specific LC-MS/MS method was developed to investigate the in vivo bio-transformation of oleuropein in rat. Rat feces and urine samples collected after oral administration were determined by liquid chromatography coupled to tandem mass spectrometry with electrospray ionization in the negative-ion mode. The assay procedure involves a simple liquid-liquid extraction of parent oleuropein and the metabolite from rat feces and urine with ethyl acetate. Chromatographic separation was operated with 0.1% formic acid aqueous and methanol in gradient program at a flow rate of 0.50 mL/min on an RP-C18 column with a total run time of 31 min. This method was successfully applied to simultaneous determination of oleuropein and its metabolites in rat feces and urine. De-glucosylation, hydrolysis, oxygenation and methylation were found to comprise the major metabolic pathway of oleuropein in rat gastrointestinal tract and three metabolites were absorbed into the blood circulatory system within 24 h after oral administration.

Olive fermentation brine: biotechnological potentialities and valorization

Olive fermentation brine causes an important local environmental problem in Mediterranean countries. Valorization is a relatively new concept in the field of industrial residue management, promoting the principle of sustainable development. One of the valorization objectives regarding food processing by-products is the recovery of fine chemicals and the production of value metabolites via chemical and biotechnological processes. In this article, recent research studies for the valorization of olive fermentation brine performed by several authors were reviewed. Special attention was paid to the metabolic products produced during table olive preparation. The selection of the corresponding valorization process will depend on the agricultural or industrial environment of the olive fermentation brine. Although some methods are strongly consolidated in this sector, other options, more respectful to the environment, should also be considered.

A comparison of Mediterranean-style and MyPyramid diets on weight loss and inflammatory biomarkers in postpartum breastfeeding women

BACKGROUND

Of postpartum women, 15%-20% retain ≥ 5 kg of their gestational weight gain, increasing risk for adult weight gain. Postpartum women are also in a persistent elevated inflammatory state. Both factors could increase the risk of obesity-related chronic disease. We hypothesized that breastfeeding women randomized to a Mediterranean-style (MED) diet for 4 months would demonstrate significantly greater reductions in body weight, body fat, and inflammation than women randomized to the U.S. Department of Agriculture's (USDA) MyPyramid diet for Pregnancy and Breastfeeding (comparison diet).

METHODS

A randomized, controlled dietary intervention trial was conducted in 129 overweight (body mass index [BMI] 27.2 ± 4.9 kg/m(2)), mostly exclusively breastfeeding (73.6%) women who were a mean 17.5 weeks postpartum. Dietary change was assessed using a validated Food Frequency Questionnaire (FFQ) before and after intervention as well as plasma fatty acid measures (gas chromatography/flame ionization detector [GC/FID]). Anthropometric measurements and biomarkers of inflammation, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), also were assessed at baseline and 4 months via enzyme-linked immunosorbent assay (ELISA).

RESULTS

Participants in both diet groups demonstrated significant (p<0.001) reductions in body weight (-2.3 ± 3.4 kg and -3.1 ± 3.4 kg for the MED and comparison diets, respectively) and significant (p ≤ 0.002) reductions in all other anthropometric measurements; no significant between-group differences were shown as hypothesized. A significant decrease in TNF-α but not IL-6 was also demonstrated in both diet groups, with no significant between-group difference.

CONCLUSIONS

Both diets support the promotion of postpartum weight loss and reduction in inflammation (TNF-α) in breastfeeding women.

Differential effects of high-carbohydrate and high-fat diet composition on metabolic control and insulin resistance in normal rats

The macronutrient component of diets is critical for metabolic control and insulin action. The aim of this study was to compare the effects of high fat diets (HFDs) vs. high carbohydrate diets (HCDs) on metabolic control and insulin resistance in Wistar rats. Thirty animals divided into five groups (n = 6) were fed: (1) Control diet (CD); (2) High-saturated fat diet (HSFD); (3) High-unsaturated fat diet (HUFD); (4) High-digestible starch diet, (HDSD); and (5) High-resistant starch diet (HRSD) during eight weeks. HFDs and HCDs reduced weight gain in comparison with CD, however no statistical significance was reached. Calorie intake was similar in both HFDs and CD, but rats receiving HCDs showed higher calorie consumption than other groups, (p < 0.01). HRSD showed the lowest levels of serum and hepatic lipids. The HUFD induced the lowest fasting glycemia levels and HOMA-IR values. The HDSD group exhibited the highest insulin resistance and hepatic cholesterol content. In conclusion, HUFD exhibited the most beneficial effects on glycemic control meanwhile HRSD induced the highest reduction on lipid content and did not modify insulin sensitivity. In both groups, HFDs and HCDs, the diet constituents were more important factors than caloric intake for metabolic disturbance and insulin resistance.

Virgin olive oil and nuts as key foods of the Mediterranean diet effects on inflammatory biomakers related to atherosclerosis

Previous epidemiological and feeding studies have observed that adherence to Mediterranean diet (Med-Diet) is associated with reduced cardiovascular risk. However, the molecular mechanisms involved are not fully understood. Since atherosclerosis is nowadays considered a low-grade inflammatory disease, recent studies have explored the anti-inflammatory effects of a Med-Diet intervention on serum and cellular biomarkers related to atherosclerosis. In two sub-studies of the PREDIMED (PREvencion con DIeta MEDiterranea) trial, we analyzed the effects at 3 months of two Med-Diet interventions supplemented with either virgin olive oil (VOO) or nuts compared with a control low-fat diet (LFD). Both Med-Diets showed an anti-inflammatory effect reducing serum C-reactive protein, interleukin-6 (IL6) and endothelial and monocytary adhesion molecules and chemokines (P<0.05; all), whereas these parameters increased after the LFD intervention (P<0.05; all). In another substudy, we evaluated the long-term (1 year) effects of these interventions on vascular risk factors in 516 high-risk subjects, as well as the effect of different Med-Diet components in the reduction of these biomarkers. At 1 year, the Med-Diet groups had significant decreases in the plasma concentrations of IL6, tumor necrosis factor receptor (TNFR) 60 and TNFR80 (P<0.05), while intercellular adhesion molecule 1 (ICAM-1), TNFR60 and TNFR80 concentrations increased in the LFD group (P<0.002). In addition, those allocated in the highest tertile of VOO and vegetables consumption had a significant diminution of plasma TNFR60 concentration compared with those in tertile 1 (P<0.02). In conclusion, Med-Diet exerts an anti-inflammatory effect on cardiovascular system since it down-regulates cellular and circulating inflammatory biomarkers related to atherogenesis in subjects at high cardiovascular risk.

Bioavailability of phenols from a phenol-enriched olive oil

Phenolic compounds are one of the main reasons behind the healthy properties of virgin olive oil (VOO). However, their daily intake from VOO is low compared with that obtained from other phenolic sources. Therefore, the intake of VOO enriched with its own phenolic compounds could be of interest to increase the daily dose of these beneficial compounds. To evaluate the effectiveness of enrichment on their bioavailability, the concentration of phenolic compounds and their metabolites in human plasma (0, 60, 120, 240 and 300 min) from thirteen healthy volunteers (seven men and six women, aged 25 and 69 years) was determined after the ingestion of a single dose (30 ml) of either enriched virgin olive oil (EVOO) (961·17 mg/kg oil) or control VOO (288·89 mg/kg oil) in a cross-over study. Compared with VOO, EVOO increased plasma concentration of the phenol metabolites, particularly hydroxytyrosol sulphate and vanillin sulphate (P < 0·05). After the consumption of VOO, the maximum concentration of these peaks was reached at 60 min, while EVOO shifted this maximum to 120 min. Despite these differences, the wide variability of results indicates that the absorption and metabolism of olive oil phenols are highly dependent on the individual.

Dietary monounsaturated fatty acids appear not to provide cardioprotection

Dietary interventions have been consistently proposed as a part of a comprehensive strategy to lower the incidence and severity of coronary heart disease (CHD), in the process providing long-term cardioprotection. Replacement of dietary saturated fatty acids (SFA) with higher intakes of monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) has been reported to be inversely associated with risk of CHD. The observed lower incidence of CHD among populations consuming a Mediterranean-type diet, mainly enriched in MUFA from olive oil, has long supported the belief that MUFA are an optimal substitution for SFA. However, both epidemiologic and interventional studies suggest that although substituting MUFA-rich foods for SFA-rich foods in the diet can potentially lower total plasma cholesterol concentrations, this substitution does not lower the extent of coronary artery atherosclerosis. In addition, although recent evidence suggests that the source of MUFA (animal fat vs vegetable oils) may differentially influence the correlation between MUFA intake and CHD mortality, animal studies suggest that neither source is cardioprotective.

Simultaneous quantification of oleuropein and its metabolites in rat plasma by liquid chromatography electrospray ionization tandem mass spectrometry

Oleuropein (OE) is the cardinal bioactive compound derived from Olea europaea and possesses numerous beneficial properties for human health. However, despite the plethora of analytical methods that have studied the biological fate of olive oil-derived bioactive compounds, no validated methodology has been published to date for the simultaneous determination of OE, along with all its major metabolites. In this study, a liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI MS/MS) method has been developed and validated for the quantification of OE, simultaneously with its main metabolites hydroxytyrosol, 2-(3,4-dihydroxyphenyl)acetic acid, 4-(2-hydroxyethyl)-2-methoxy-phenol or homovanillyl alcohol, 2-(4-hydroxy-3-methoxyphenyl)acetic acid or homovanillic acid, and elenolic acid in rat plasma matrix. Samples were analyzed by LC-ESI MS/MS prior to and after enzymatic treatment. A solid-phase extraction step with high mean recovery for all compounds was performed as sample pretreatment. Calibration curves were linear for all bioactive compounds over the range studied, while the method exhibited good accuracy, intra- and inter-day precision. The limit of detection was in the picogram range (per milliliterof plasma) for HT and OE and in the nanogram range (per milliliter of plasma) for the other analytes, and the method was simple and rapid. The developed methodology was successfully applied for the simultaneous quantification of OE and its aforementioned metabolites in rat plasma samples, thus demonstrating its suitability for pharmacokinetics, as well as bioavailability and metabolism studies.

Anti-inflammatory effects of the Mediterranean diet: the experience of the PREDIMED study

Several epidemiological and clinical studies have evaluated the effects of a Mediterranean diet (Med-Diet) on total cardiovascular mortality, and all concluded that adherence to the traditional Med-Diet is associated with reduced cardiovascular risk. However, the molecular mechanisms involved are not fully understood. Since atherosclerosis is nowadays considered a low-grade inflammatory disease, recent studies have explored the anti-inflammatory effects of a Med-Diet intervention on serum and cellular biomarkers related to atherosclerosis. In a pilot study of the PREvencion con DIeta MEDiterranea (PREDIMED) trial, we analysed the short-term effects of two Med-Diet interventions, one supplemented with virgin olive oil and another with nuts, on vascular risk factors in 772 subjects at high risk for CVD, and in a second study we evaluated the effects of these interventions on cellular and serum inflammatory biomarkers in 106 high-risk subjects. Compared to a low-fat diet, the Med-Diet produced favourable changes in all risk factors. Thus, participants in both Med-Diet groups reduced blood pressure, improved lipid profile and diminished insulin resistance compared to those allocated a low-fat diet. In addition, the Med-Diet supplemented with virgin olive oil or nuts showed an anti-inflammatory effect reducing serum C-reactive protein, IL-6 and endothelial and monocytary adhesion molecules and chemokines, whereas these parameters increased after the low-fat diet intervention. In conclusion, Med-Diets down-regulate cellular and circulating inflammatory biomarkers related to atherogenesis in subjects at high cardiovascular risk. These results support the recommendation of the Med-Diet as a useful tool against CVD.

Cardioprotective and neuroprotective roles of oleuropein in olive

Traditional diets of people living in the Mediterranean basin are, among other components, very rich in extra-virgin olive oil, the most typical source of visible fat. Olive is a priceless source of monounsaturated and di-unsaturated fatty acids, polyphenolic antioxidants and vitamins. Oleuropein is the main glycoside in olives and is responsible for the bitter taste of immature and unprocessed olives. Chemically, oleuropein is the ester of elenolic acid and 3,4-dihydroxyphenyl ethanol, which possesses beneficial effects on human health, such as antioxidant, antiatherogenic, anti-cancer, anti-inflammatory and antimicrobial properties. The phenolic fraction extracted from the leaves of the olive tree, which contains significant amounts of oleuropein, prevents lipoprotein oxidation. In addition, oleuropein has shown cardioprotective effect against acute adriamycin cardiotoxicity and an anti-ischemic and hypolipidemic activities. Recently, oleuropein has shown neuroprotection by forming a non-covalent complex with the Aβ peptide, which is a key hallmark of several degenerative diseases like Alzheimer and Parkinson. Thus, a large mass of research has been accumulating in the area of olive oil, in the attempt to provide evidence for the health benefits of olive oil consumption and to scientifically support the widespread adoption of traditional Mediterranean diet as a model of healthy eating. These results provide a molecular basis for some of the benefits potentially coming from oleuropein consumption and pave the way to further studies on the possible pharmacological use of oleuropein to prevent or to slow down the cardiovascular and neurodegenerative diseases.

Oleuropein in olive and its pharmacological effects

Olive from Olea europaea is native to the Mediterranean region and, both the oil and the fruit are some of the main components of the Mediterranean diet. The main active constituents of olive oil include oleic acid, phenolic constituents, and squalene. The main phenolic compounds, hydroxytyrosol and oleuropein, give extra-virgin olive oil its bitter, pungent taste. The present review focuses on recent works that have analyzed the relationship between the major phenolic compound oleuropein and its pharmacological activities including antioxidant, anti-inflammatory, anti-atherogenic, anti-cancer activities, antimicrobial activity, antiviral activity, hypolipidemic and hypoglycemic effect.

Effects of Mediterranean diets with low and high proportions of phytate-rich foods on the urinary phytate excretion

BACKGROUND

Important health benefits have been reported recently to phytate intake. This includes the prevention of pathological calcifications such as renal calculi, dental calculi and cardiovascular calcification, due its action as crystallization inhibitor of calcium salts, and as preventive of cancer.

AIM OF STUDY

The aim of this study was to establish a relation between the intake of phytate, through consumption of typical components of the Mediterranean diet (including nuts), and its excretion in urine.

METHODS

This study recruited participants from subjects included in a larger trial (PREDIMED) of food habits, that were assigned to one of two diet groups: (1) the Mediterranean diet with low proportion of phytate-rich food group, where participants were asked to maintain their usual diet; and (2) the Mediterranean diet with high proportion of phytate-rich food group, where participants were asked to increase phytate-rich foods in their diet. Phytate intake was assessed on the basis of a food frequency questionnaire. Urinary phytate excretion was determined in 2-h urine samples.

RESULTS

The overall phytate consumption of the Mediterranean diet with high proportion of phytate-rich food group (672 +/- 50 mg) was significantly higher than the Mediterranean diet with low proportion of phytate-rich food group (422 +/- 34 mg), representing a 59% difference. Urinary phytate excretion was also significantly higher (54%) in the Mediterranean diet with high proportion of phytate-rich food group (1,016 +/- 70 microg/L) than the Mediterranean diet with low proportion of phytate-rich food group (659 +/- 45 microg/L).

CONCLUSIONS

Mediterranean diets high in whole cereals, legumes and nuts compared to Mediterranean diets low in these phytate-rich foods increase the urinary phytate excretion in humans.

Effects of extra virgin olive oil supplementation at two different low doses on lipid profile in mild hypercholesterolemic subjects: a randomised clinical trial

Olive oil, the principal fat of Mediterranean Diet, is known to improve several cardiovascular risk factors at relatively high doses together with intensive modifications of dietary habits. Since this is hard to obtain in the long term, an intervention with encapsulated oil supplements might be more feasible. Aim of this preliminary study was to investigate the effects of the supplementation of a moderate amount of encapsulated extra virgin olive oil vs a lower dose in mildly hypercholesterolemic subjects, as part of their established diet, on blood lipid profile. A prospective randomized study was performed. Thirty-four mildly hypercholesterolemic subjects [age, mean+/-SD: 46+/-7 yr; total cholesterol (TC): 235+/-28 mg/dl] were randomly assigned to receive 2 g (group A) or 4 g (group B) per os of extra-virgin olive oil for 3 months. TC, triglycerides (TG), LDL cholesterol, HDL cholesterol, apolipoprotein A1 (Apo-AI), apolipoprotein B (Apo-B), and atherogenic index of plasma (AIP) were evaluated at the beginning and at the end of the study. In group B, but not in group A, a significant reduction of Apo-B values (7%) was observed; TG concentrations showed a trend towards reduction and Apo-A1 values a trend towards increase (9%). A significant decrease in Apo-B/Apo-A1 ratio (p<0.01) was also observed in group B. Extra virgin olive oil supplementation significantly decreased AIP from baseline in group B (p<0.05). The results of the present study seem to suggest that the daily supplementation, on top of the normal diet, of at least 4 g of extra virgin olive oil, in mildly hypercholesterolemic subjects, is associated to favorable modifications of the plasmatic lipid profile.

Antiviral efficacy against hepatitis B virus replication of oleuropein isolated from Jasminum officinale L. var. grandiflorum

ETHNOPHARMACOLOGICAL RELEVANCE

Jasminum officinale L. var. grandiflorum (JOG) is a folk medicine used for the treatment of hepatitis in south of China. Phytochemical studies showed that secoiridoid glycosides are the typical constituents of this plant.

AIM OF THE STUDY

The present study was undertaken to evaluate the effect of oleuropein (Ole) derived from the flowers of JOG on hepatitis B virus (HBV) replication in HepG2 2.2.15 cell line in vitro and duck hepatitis B virus (DHBV) replication in ducklings in vivo.

MATERIAL AND METHODS

The extracellular hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) concentrations in cell culture medium were determined by ELISA. DHBV in duck serum was analyzed by dot blot.

RESULTS

Ole blocks effectively HBsAg secretion in HepG2 2.2.15 cells in a dose-dependent manner (IC(50)=23.2 microg/ml). Ole (80 mg/kg, intraperitoneally, twice daily) also reduced viremia in DHBV-infected ducks.

CONCLUSION

Ole therefore warrants further investigation as a potential therapeutic agent for HBV infection.

Oleic acid content is responsible for the reduction in blood pressure induced by olive oil

Numerous studies have shown that high olive oil intake reduces blood pressure (BP). These positive effects of olive oil have frequently been ascribed to its minor components, such as alpha-tocopherol, polyphenols, and other phenolic compounds that are not present in other oils. However, in this study we demonstrate that the hypotensive effect of olive oil is caused by its high oleic acid (OA) content (approximately 70-80%). We propose that olive oil intake increases OA levels in membranes, which regulates membrane lipid structure (H(II) phase propensity) in such a way as to control G protein-mediated signaling, causing a reduction in BP. This effect is in part caused by its regulatory action on G protein-associated cascades that regulate adenylyl cyclase and phospholipase C. In turn, the OA analogues, elaidic and stearic acids, had no hypotensive activity, indicating that the molecular mechanisms that link membrane lipid structure and BP regulation are very specific. Similarly, soybean oil (with low OA content) did not reduce BP. This study demonstrates that olive oil induces its hypotensive effects through the action of OA.