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The Treatment of Hypertension with Nutrition, Nutritional Supplements, Lifestyle and Pharmacologic Therapies
Published in Stephen T. Sinatra, Mark C. Houston, Nutritional and Integrative Strategies in Cardiovascular Medicine, 2022
The Mediterranean diet (MedDiet), which is rich in olive oil and the supplement olive leaf extract (OLE), reduces BP and CVD in most clinical trials [2–14,151–173]. In an open study over 2 months, 40 borderline hypertensive monozygotic twins given either 500 or 1,000 mg/day of olive leaf extract had significant reductions in BP of 6/5 mmHg (500 mg of OLE) and 13/5 mmHg reduction (1,000 of OLE) compared to controls [171]. In another randomized doublle blind placebo control and control (RDBPC) trial, the BP decreased 8/6 mmHg (p ≤ 0.01) in office and 24-hour ABM, and the need for antihypertensive medications was reduced by 48% in the MUFA group (p < 0.005) [151]. Extra virgin olive oil (EVOO) lowered the SBP by 14 mmHg in elderly hypertensive patients (p < 0.01) [152,153]. EVOO contains lipid-soluble phytonutrients such as nitrates and polyphenols which lower BP by reducing oxidative stress and oxLDL, blocking the AT1R, altering RAAS and endothelin gene expression, increasing nitric oxide levels and endothelial-induced vasodilation, and blocking calcium channels similar to a CCB [148,151,155,162–164]. EVOO with a total phenol content of at least 161 mg/kg at 20–40 g (2–4 tablespoons) per day will significantly lower SBP in about 3 weeks. EVOO with 300 mg/kg of total phenols may also decrease DBP [2–5,168].
Role of Natural Polyphenols in Oxidative Stress: Prevention of Diabetes
Published in Megh R. Goyal, Durgesh Nandini Chauhan, Assessment of Medicinal Plants for Human Health, 2020
Brahm Kumar Tiwari, Kanti Bhooshan Pandey
Studies provide results that many plant polyphenols may modulate insulin sensitivity such as green tea catechins like Epigallocatechin-3-gallate (EGCG)15,50, chlorogenic acid, 4-caffeoylquinic, gallic acid, 5-hydroxymethylfurfural, protocatechuic acid70, cinnamon polyphenols (catechin, epicatechin)72, anthocyanin (cyanidin 3-glucoside)76, resveratrol13, olive leaf polyphenols (vpigenenin, flavonoid, verbascoside, oleic acid, quercetin, luteolin, rutin, oleuropein, hydroxytyrosol, and kaempferol).24
Impact of Dietary Polyphenols on Arterial Stiffness
Published in Catherina Caballero-George, Natural Products and Cardiovascular Health, 2018
Tess De Bruyne, Lynn Roth, Harry Robberecht, Luc Pieters, Guido De Meyer, Nina Hermans
Acute ingestion of olive polyphenols oleuropein and hydroxytyrosol in an olive leaf extract (51 mg OLE; 10mg HT) improved vascular function (digital volume pulse-stiffness index) and ex vivo IL-8 production. The observed effects were related to analysis of the phenolic metabolites in urine (n = 18) (Lockyer et al., 2015). A recent double-blind randomized controlled trial confirmed this antioxidant effect and showed that a combination of red yeast rice and olive extract (containing 9.32 mg HT) decreased SBP and DBP (n = 50; 8 weeks) (Hermans et al., 2017; Verhoeven et al., 2015). An olive fruit extract standardized in hydroxytyrosol reduced the cardio-ankle vascular index (CAVI) in subjects with arterial stiffness risk (Pais et al., 2016).
Neuroprotective effects of oleuropein on retina photoreceptors cells primary culture and olive leaf extract and oleuropein inhibitory effects on aldose reductase in a diabetic model: Meriones shawi
Published in Archives of Physiology and Biochemistry, 2022
Maha Benlarbi, Hedya Jemai, Khouloud Hajri, Sihem Mbarek, Emna Amri, Mariem Jebbari, Imane Hammoun, Basma Baccouche, Nourhène Boudhrioua Mihoubi, Ayachi Zemmal, Rafika Ben Chaouacha-Chekir, Wissal Dhifi
According to the main results, olive leaf extract and oleuropein could be used to prevent diabetes complications. As perspectives of the present work, it is interesting to test olive leaf aqueous extract at different concentrations to evaluate its AR inhibitory potential. It is also interesting to test the different fractions of the aqueous extract to identify the active one. Furthermore, we have to explore in depth the mechanisms of oleuropein neuroprotective effect. Moreover, in the light of these results, it appears that olive leaves could be exploited as nutraceuticals providing substantial health benefits especially in the prevention and/or treatment of diabetes. However, this depends upon many parameters such as safety, long-term adverse effects, and toxicity as well as supplementation studies and clinical trials in humans.
Chemical composition, antioxidant activities, in an allergic asthma model, of Olea europaea L. leaf extracts from Collo (Skikda, Algeria)
Published in Drug and Chemical Toxicology, 2022
Zineb Rouibah, Amir Ben Mensour, Ons Rekik, Mahieddine Boumendjel, Faiza Taibi, Mohamed Bouaziz, Abdelfattah El Feki, Mahfoud Messarah, Amel Boumendjel
Therefore, the main active component of olive leaf extract is oleuropein, a natural product of the secoiridoid group that is the main polyphenol of fresh olives. However, because of its bitter taste, it is totally or partially eliminated or transformed, in the tree, to produce this edible fruit. Such a compound consists of a molecule of elenolic acid linked to ortho-diphenol HT by an ester bond and to a glucose molecule by a glycosidic bond (Panizzi et al.1960). These products derived from oleuropein (tyrosol and HT) are usually found in high concentrations in extra virgin oil due to the hydrolysis of oleuropein during the processing of the oil (Vissers et al.2002). On the other hand, human pharmacokinetic studies have shown that the conjugated metabolites (sulfates and glucuronids) of HT are the major metabolites of oleuropein recovered in plasma and urine after the consumption of olive leaf extract (De Bock et al.2013).
Standardized Olea europaea L. leaf extract exhibits protective activity in carbon tetrachloride-induced acute liver injury in rats: the insight into potential mechanisms
Published in Archives of Physiology and Biochemistry, 2020
Sašenka Vidičević, Jelena Tošić, Željka Stanojević, Aleksandra Isaković, Dragana Mitić, Dušica Ristić, Dragana Dekanski
The search for effective, non-toxic natural compounds with antioxidative activity has been intensified in recent years (Dimitrios 2006). There is an increasing interest in the use of natural antioxidants in the treatment of hepatic diseases also, and these products, especially total medicinal plant extracts, emerged as a promising source of hepatoprotective compounds (Domitrovic and Potocnjak 2016, Thompson et al.2017, Rahmouni et al.2018, Slama et al.2018). There is numerous non-clinical and clinical literature data on the pharmacological activity of different olive leaf extracts and especially their strong antioxidative potential (Özcan and Matthäus 2017). Recently, 14-day post-treatment with Olea europaea leaf extract was effective in reducing hepatic damage caused by CCl4 by reducing lipid peroxidation, regulating antioxidant enzymes, and minimizing DNA damage (Ustuner et al.2018). It was also found that Olea europaea fruit pulp extract could prevent CCl4-induced acute and chronic liver degeneration in mice. The extract showed similar or significantly greater activity when compared to the standard agent silymarin at the same dose tested (Kang and Koppula 2014). Long-term pre-treatment with methanolic extract of Saudi olive leaf significantly reduced serum AST and ALT activities induced by CCl4 in rabbits. This hepatoprotective effect was also explained by its antioxidant activity and was comparable with effect of a reference drug, silymarin (Hamad 2015). In addition, it is proven that olive leaf extract possesses a nephroprotective effect in CCl4-induced kidney damage (Al-Sowayan and Mousa 2014).