A review of olive, grape, garlic, rosemary and saffron properties against cardiovascular diseases

Cardiovascular problems are the leading cause of disease and mortality worldwide. Plant extracts, rich in bioactive compounds, have contributed significantly to the development of drugs, as they offer therapeutic potential for several of these diseases. However, their use is limited by possible side effects, drug-drug interactions and the lack of scientific evidence from quality preclinical and clinical studies.

During the 2023/24 academic year, biologist Mateu Anguera Tejedor made an important contribution in this field with his final year Biology degree project at the UAB, tutored by the then postdoctoral researcher at the Institut de Neurociències of the UAB (INc-UAB) and current lecturer at the Faculty of Pharmacy and Food Sciences of the University of Barcelona René Delgado.

The study, recently published as a scientific article in the journal Food Bioscience, provides an overview of the mechanisms of action and the preclinical and clinical evidence, as well as the adverse effects of essential bioactive compounds derived from a group of selected Mediterranean plants, which form part of the Mediterranean diet.

Among the species analysed, six representative plants and their major active components are reported: garlic (Allium sativum, with diallyl trisulfide, allicin and S-allyl [cysteine]), hawthorn shrub (Crataegus monogyna, with quercetin, apigenin and chlorogenic acid), saffron (Crocus sativus, with crocin and safranal), olive (Olea europaea, with oleic acid, oleuropein, hydroxytyrosol and oleacein), rosemary (Salvia rosmarinus, with rosmarinic acid and carnosic acid) and grapevine (Vitis vinifera, with resveratrol). The review focused on the most important pharmacological mechanisms, including their antioxidant, anti-inflammatory and vasodilatory actions, as well as their regulation of lipid metabolism, which may be relevant for conditions such as atherosclerosis and hypertension. The results show that these active components are promising in the potential treatment of atherosclerosis and could reduce the risk of myocardial infarction and stroke.

In addition to summarising the current scientific evidence, the study provides a reference guide for future research by identifying potential knowledge gaps and offering timely recommendations for designing preclinical and clinical studies in this area. Key areas for future exploration include the long-term safety of these compounds, the evaluation of their synergistic effects when consumed as part of a Mediterranean diet, and the need to establish standardised protocols in controlled clinical settings. By broadening the scientific basis of these traditional remedies, this review may help pave the way for their use as active pharmaceutical ingredients in the development of future phytomedicines.

Combined ingestion could alter the efficacy of individual extracts

The research team believes that the use of these natural extracts is promising, but their combined ingestion could influence therapeutic outcomes due to the “matrix effect”, which implies that dietary components can alter the efficacy of each extract, either enhancing or diminishing their individual benefits. Understanding this interaction is essential to optimise the therapeutic application of these plant extracts in a dietary context. It is important to recognise that there is often a lack of robust evidence of the impact of natural extracts in humans, and therefore researchers caution that “the label of ‘natural’ does not guarantee safety, and this emphasises the need to prioritise pharmacokinetic, toxicological and clinical studies to evaluate their efficacy, safety and efficiency in comparison with existing drugs”.

The study was carried out by the research group led by Francesc Jiménez Altayó. Lecturer in the Department of Pharmacology, Therapeutics and Toxicology at the UAB and researcher at the Centre for Biomedical Research in Cardiovascular Diseases Network (CIBERCV) and the UAB Institut de Neurociències (INc-UAB), Jiménez Altayó was tutor of lecturer René Delgado Hernández, Cuban-born researcher from the University of Havana, assigned during the 2022/23 academic year to the María Zambrano programme in the Department of Pharmacology, Therapeutics and Toxicology of the Faculty of Medicine of the UAB and currently lecturer in the Unit of Clinical Pharmacy and Pharmaceutical Care in the Faculty of Pharmacy and Food Sciences of the University of Barcelona. Teaching and research staff from Cuban and Chilean institutions with renowned experience in the field of pharmacology of natural products also participated in the preparation and final publication of this study.

Reference article:

Anguera-Tejedor M., Garrido G, Garrido-Suárez B. B., Ardiles-Rivera A., Bistué-Rovira A., Jiménez-Altayó F., Delgado-Hernández R. Exploring the Therapeutic Potential of Bioactive Compounds from Selected Plant Extracts of Mediterranean Diet Constituents for Cardiovascular Diseases: A Review of Mechanisms of Action, Clinical Evidence, and Adverse Effects. Food Bioscience 2024: 105487. ISSN 2212-4292. https://doi.org/10.1016/j.fbio.2024.105487