Cardioprotective Effect of a Virgin Olive Oil Enriched with Bioactive Compounds in Spontaneously Hypertensive Rats

Abstract

Olive oil and its derivatives have been described to exert beneficial effects on hypertensive states and cardiovascular disease prevention. We studied the effects of chronic consumption of extra virgin olive oil (EVOO), enriched in bioactive compounds from olive fruit and leaves, on blood pressure, endothelial function, oxidative and inflammatory status, and circulating cholesterol levels, in spontaneously hypertensive rats (SHR). Thirty SHR were randomly assigned to three groups: a control untreated SHR group, an SHR group (1 mL/rat/day) of a control olive oil (17.6 mg/kg of phenolic compounds), and an SHR group (1 mL/rat/day) of the enriched EVOO (750 mg/kg of phenolic compounds) for eight weeks. Ten Wistar Kyoto rats (WKY) were included as healthy controls. Long-term administration of the enriched EVOO decreased systolic blood pressure and cardiac hypertrophy, and improved the ex vivo aortic endothelial dysfunction measured in SHR. Moreover, enriched oil supplementation reduced the plasma levels of Angiotensin II and total cholesterol, and the urinary levels of endothelin-1 and oxidative stress biomarkers, while pro-inflammatory cytokines were unaffected. In conclusion, sustained treatment with EVOO, enriched in bioactive compounds from the olive fruit and leaves, may be an effective tool for reducing blood pressure and cholesterol levels alone or in combination with pharmacological anti-hypertensive treatment.

Chemical Characterisation and Antihypertensive Effects of Locular Gel and Serum of Lycopersicum esculentum L. var. “Camone” Tomato in Spontaneously Hypertensive Rats

“…It is plausible that the anti-hypertensive effect shown by Gs was due to more than one component or to an additive effect of polyphenols and glycoalkaloids, which need to be administered for a long period of time. The effects of Gs could be more pronounced if treatment is started before the onset of hypertension and continued at length, as indicated in a recent paper on the anti-hypertensive effect of an enriched olive oil, that produced a reduction in blood pressure after five weeks of treatment and reduced cardiac hypertrophy after eight weeks of treatment [4,28]. A similar observation was also reported by other authors [29].…”

“…Four weeks of Gs treatment may not be enough to restore all cardiovascular parameters, especially those linked to morphological modifications. In fact, the literature suggests that treatments with natural compounds inducing morphological modifications have to be continued for longer periods [28]. Our results show that none of the treatments affected plasma glucose and triglycerides, which in our study were not significantly different in WKYs and SHRs.…”

Acute/Subacute and Sub-Chronic Oral Toxicity of a Hidroxytyrosol-Rich Virgin Olive Oil Extract

“…Therefore, it is desirable to increase the polyphenol content of VOO in order to improve its benefits. In this way, previous studies have demonstrated the cardioprotective effect of VOO enriched in bioactive compounds from the olive oil in animals [8] and humans [9,10]. In fact, recent studies have shown a strong ergogenic effect on physical activity and remodeling of more efficient mitochondrial super-complexes with lower reactive oxygen-derived species production at doses 20 mg/kg and 300 mg/kg [11,12].…”

Effects of Olive Oil on Blood Pressure: Epidemiological, Clinical, and Mechanistic Evidence

“…In line with this hypothesis, in the same SHR model, the administration of EVOO [75], pomace oil [76], or related antioxidant polyphenolic components (oleuropein, hydroxytyrosol) was shown to lower BP significantly. Investigated mechanisms range across anti-oxidative activities [75,77], changes of aminopeptidase activities favoring the production of Ang 2-10 (in this way compensating the activity of Ang II) and the clearance of Ang III and Ang IV [75], increase in the endothelial nitric oxide synthase (eNOS) expression [76,78], and reduction of plasma Ang II [75] (Figure 4). Correspondingly, our previous research has shown that OO polyphenols and related human serum metabolites, as found in human serum upon EVOO ingestion, can decrease the endothelial activity and expression of NADPH oxidase, as shown by the reduced levels of intracellular ROS and decreased expression and activity of MMP-2 and MMP-9 in endothelial cells [79,80] and adipocytes [81,82].…”