Effects Of Olive Leaf Extract Research Articles

Effect of olive leaf extract on skeletal muscle in disuse-induced muscle atrophy model rats

Effect of olive leaf extract on skeletal muscle in disuse-induced muscle atrophy model rats

Investigation of the Genotoxic, Cytotoxic, Apoptotic, and Oxidant Effects of Olive Leaf Extracts on Liver Cancer Cell Lines.

Hepatocellular carcinoma (HCC) is the seventh most common cancer and the third leading cause of tumor-related deaths worldwide. Mechanisms underlying tumor onset, progression, and metastasis in the case of HCC have not been adequately studied. In this study, we aimed to investigate the genotoxic, cytotoxic, apoptotic and oxidant effects of olive leaf extract (OLE) on HCC cells. H4IIE Rattus norvegicus hepatoma cells and Rattus norvegicus healthy liver clone-9 cells were treated with the increasing concentrations of OLEs (250-2000 ppm) in ethanol, acetone, dichloromethane, and methanol. ATP cell viability, intracellular reactive oxygen species generation levels, double staining test with acridine orange/ethidium bromide, comet assay, levels of interleukin 1-beta (IL-1β), IL-6, and tumor necrosis factor alpha were measured. Significance was determined using ANOVA test. Apoptotic, genotoxic, cytotoxic, and oxidative effects of OLEs increased with the increasing concentrations as compared to controls in H4IIE cells (p<0.001). This is the first study to show a significant and selective cytotoxic activity of OLEs in the selected H4IIE cancer cell lines. OLEs could selectively increase the apoptotic damage and show anti-proliferative and pro-apoptotic properties against the H4IIE cells. They could be recommended as potential nutraceuticals in the prevention of cancer.

The effect of olive leaf extract containing natural antioxidant on the formation of heterocyclic aromatic amines in oil free pan-cooked salmon

Rationale: Heterocyclic aromatic amines (HCA) are mutagenic and carcinogenic compounds that are formed at low levels (ng / g) by cooking protein-rich foods such as meat and fish. These compounds play an important role in the etiology of human cancer, so researchers suggest that the formation of HCAs should be minimized. It has been reported that antioxidants can reduce HCA formation by retaining the free radicals formed in HCA formation mechanism and Maillard reaction. The aim of this study was to investigate the preventive effects of the olive leaf extract on the formation of HCAs.

Potential benefit of olive leaf extract in cervical spondylotic myelopathy model

IntroductionCervical spondylosis is the most common cause of myelopathy in the cervical due to chronic compression of the spinal cord in patients aged 55 years or older. Recent studies suggest that olive extracts suppress inflammation and reduce stress oxidative injury. The purpose of this study was to determine the potential neuroprotective effects of olive leaf extract (OLE) in an experimental cervical spondylotic myelopathy model. MethodsThis study was divided into 6 groups; Control Negative (Sham-Operated) Group, Control Positive 1 & 2 (early chronic and chronic), Treatment Groups 1, 2 & 3 (prophylactic, concomitant & late). Olive leaf extract (OLE) give 350 mg/kg BW and spinal cord sample was taken at the compression level C5. Histopathological assessment and immunohistochemistry of Amyloid-β, p-Tau, TDP-43 dan CD-68 dan evaluation of functional motoric outcome was done before animals were terminated. ResultsChronic spinal cord compression increased the expression of Amyloid-β, p-Tau, TDP-43 dan CD-68. OLE 350 mg/kg BW decreased the expression of these biomarkers and increased functional motoric outcome, especially as prophylactic dan concomitant treatment. DiscussionThese findings indicate that OLE may be effective in protecting cervical spondylotic myelopathy.

Study of Therapeutic Effects of Olive Leaf Extract on Phenylhydrazine-Induced Anemia Mice Model

IntroductionAnemia is the most common blood disorder which affects billions of people, especially young adults and women. However, currently available treatments of anemia are with limitations and adverse effects. Therefore, natural resources have been receiving considerable attention as complementary or alternative hematinic agents in recent years. In this regard, olive leaf extract (OLE) is rich in bioactive phenolic compounds and has been reported to have anti-inflammatory, antioxidant and neuroprotective effects (Vogel et al., 2015). Our previous study showed treatment with water extract of olive leaf (WOL) for 12 days could induce erythroid differentiation in human hematopoietic stem cells (hHSCs) and showed potential in oxygen and iron homeostasis, haem metabolism, and hemoglobin (Hb) biosynthesis (Kondo et al., 2021). In the present study, we aimed to investigate the therapeutic effects of WOL on the phenylhydrazine (PHZ)-induced mice model of anemia and explore its underlying molecular mechanism.MethodsTotal 63 male ICR mice (four weeks old) were randomly divided into three groups: control, PHZ and WOL groups. Mice in the WOL group were orally administered with 150 mg/kg body weight of WOL (diluted by saline) every day, while mice in the other two groups received saline. After two weeks of WOL pretreatment, PHZ was injected intraperitoneally (60 mg/kg body weight) to PHZ and WOL groups. The mice were dissected on day0 (before PHZ injection), day1, day3, day5, and day7 after PHZ injection. We collected blood for hematologic tests during dissection and liver, kidney, intestine, bone marrow, and spleen samples. We next checked the iron homeostasis-related gene expressions by real-time PCR: hepcidin (Hamp) in liver, ferroportin (Fpn) in spleen and intestine.Results and DiscussionAfter anemia was induced, WOL group showed a significant increase in the number of reticulocytes, the erythroid progenitors, compared to that of in PHZ group on Day 5. Simultaneously, plasma iron level on Day 5 and Hb level on Day7 was significantly decreased in the WOL group compared to the PHZ group. These results suggest that during anemia, the WOL group had rapid erythropoiesis, which in turn caused a rapid consumption of Hb and iron.Additionally, mRNA expression of Hamp in liver was significantly decreased on Day 5, whereas Fpn expressions in spleen and intestine were significantly increased on Day 5 and Day 7 in the WOL group compared to the PHZ group.Hamp regulates plasma iron concentrations as well as systemic iron metabolism by interacting with its receptor Fpn, a transmembrane iron-exporter. In intestine, Fpn controls iron absorption from food intake, while in spleen, Fpn regulates phagocytosis of senescent erythrocytes by the macrophages. Decreased Hamp expression and increased Fpn expression by WOL treatment suggest increased levels of absorbed and recycled iron to meet the demand for erythropoiesis. Altogether, our findings indicate that WOL could regulate iron homeostasis in the early stage of anemia to promote the differentiation of erythroid progenitors.ConclusionOur study suggests that WOL treatment downregulates Hamp expression in liver and increased Fpn expressions in the intestine and spleen, leading to increased absorbed iron in the intestine and recycled iron in the spleen (Figure 1). Therefore, WOL may have therapeutic potential in anemia through regulating iron homeostasis and promoting erythroid differentiation. However, further studies are required to confirm these findings and to elucidate the molecular mechanisms.Our previous study showed that 12-day treatment of hHSCs with WOL could upregulate the expression of hypoxia-inducible factor 1-a (HIF1A) (Kondo et al., 2021), a key modulator of the transcriptional response to hypoxia and has been reported to regulate erythropoietin (Epo) production, which plays an important role in erythropoiesis. So, we hypothesize that WOL treatment would activate HIF1A in anemia-induced mice model, thus regulating Epo production to accelerate erythroid maturation. HIF2A is also reported to regulate Epo in kidney and Fpn in intestine to regulate erythropoiesis (Andrew J., et al., 2019).Therefore, we will investigate Epo expression in kidney, Hif1a and Hif2a expressions in kidney and intestine, and transferrin receptor (Tfrc, erythroid marker) in bone marrow. All gene expressions will be confirmed in protein levels also. [Display omitted] DisclosuresSuidasari: Nutrition Act Co. Ltd.: Current Employment. Yokozawa: Nutrition Act Co. Ltd.: Current Employment. Yamauchi: Nutrition Act Co. Ltd.: Current Employment.

Protective effects of olive leaf extract against reproductive toxicity of the lead acetate in rats.

Lead acetate (PbAc) is one of the toxic metals in the environment which causes many effects on different organs of the body. And due to the importance of the olive tree, with its healthy and protective elements against many diseases, the leaf extract of this tree was chosen in our study. Therefore, the aim of this study was to investigate the role of olive leaf (Olea europea L.) extract (OLE) against PbAc-induced sperm toxicity, sex hormone changes, oxidative stress, and histopathological changes in rats. Twenty male Wistar rats were divided into four groups (group 1, as control; group 2, OLE; group 3, PbAc; group 4, PbAc+OLE). In the PbAc group, the body weight, testis and epididymis weights, sexual hormones, sperm characteristics, GR, GPx, GST, GSH, SOD, and CAT were significantly decreased, and the sperm abnormality and TBARS level were significant increase when compared with control and OLE groups. Also, numerous damages to testicular tissue were observed in the PbAc group when compared to the control group, while the treatment with OLE in the fourth group led to improvement of sex hormones, semen characteristics, oxidative stress, and testicular tissue damage caused by PbAc. It can be concluded that OLE has a protective and ameliorative effects against PbAc-induced oxidative stress, apoptosis and alterations in testicular tissue, and sperm quality in rats.

Antimicrobial activity of olive leaf extract on selected foodborne pathogens and its effect on thermal resistance of Listeria monocytogenes in sous vide ground beef

Antimicrobial activity of a commercial olive leaf extract (OLE) against Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli O157:H7, Escherichia coli Biotype I, Salmonella Enteritidis and Salmonella Typhimurium was tested by disc diffusion assay. The Gram negative bacteria tested in this study were more sensitive to OLE than Gram negatives. The highest antimicrobial activity was on L. monocytogenes which yielded the largest inhibitions zone. Effect of OLE on thermal resistance of L. monocytogenes was tested both in Tryptic Soy Broth supplemented with 0.6% yeast extract (TSBYE) and sous vide packed ground beef. OLE added TSBYE (0, 0.5, 1%) tubes and ground beef (0, 1%) samples were inoculated with L. monocytogenes (7-8 log cfu/ml-g) and heated at 55, 60 and 65°C up to 30, 20 and 7.5 minutes, respectively. Total reductions in TSBYE tubes added with 0.5 and 1% OLE were slightly higher than control tubes (0% OLE) for all temperatures. Counts of L. monocytogenes in sous vide packed ground beef samples added with 1% OLE and then cooked at 55°C (30 min), 60°C (20 min) and 65°C (7.5 min) were 0.31, 1.04 and 0.73 log cfu/g lower than those control samples, respectively. The results indicate that OLE included in formulation may be an additional hurdle to control L. monocytogenes in heat processed ground beef.

Antioxidant and anti-inflammatory effect of olive leaf extract treatment in diabetic rat brain.

Olive (Olea europaea L.) plays a promising role in pharmaceutical, nutraceutical, and cosmetic production. On the other hand, olive leaf is widely used in folk medicine due to its antihyperglycemic activity. For this aim, possible effects of olive leaf extract (OLE) in the brain tissue of streptozotocin-induced diabetic rats were investigated. A total of 28 male rats were divided into four equal groups as control, diabetic (single dose of 45mg/kg streptozotocin, i.p.), OLE (500mg/kg/day), and diabetic+OLE groups. The study was terminated 21days after the diabetes model was formed. At the end of the study, all the animals were sacrificed and blood and brain tissues were isolated. Relative brain weights, complete blood count, blood glycated hemoglobin, serum glucose, total protein, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, insulin, gonadal hormone levels, production and messenger ribonucleic acid(mRNA) levels of proinflammatory cytokines and mediators, total thiol, total oxidative stress, and total antioxidant status levels and fatty acid composition in brain tissue were measured in all study groups. In diabetic rats, relative brain weight and serum insulin level decreased, glycated hemoglobin, oxidative stress, production and mRNA level of proinflammatory cytokines and mediators increased, hyperglycemia, hypercholesterolemia and hypertriglyceridemia, degraded fatty acid composition, anemia, leukopenia, and thrombocytopenia occurred. After OLE treatment, a remarkable improvement in most of these parameters, except gonadal hormones, has been observed in diabetic rats. This study suggests that olive leaf can be a precious neuroprotective agent in diabetes.

Olive leaf extract effect on cardiometabolic profile among adults with prehypertension and hypertension: a systematic review and meta-analysis.

BackgroundThis systematic review and meta-analysis aimed to determine the effectiveness of olive leaf extract on cardiometabolic profiles among prehypertensive and hypertensive groups. MethodologyThe Cochrane central register of controlled trials, Medline (1966 to April week 1, 2020), Embase (1966 to April week 1, 2020) and trial registries for relevant randomized clinical trials were used. Published and unpublished randomized clinical trials were reviewed and evaluated. Random effects models were used to estimate the continuous outcomes and mean differences (MDs); both with 95% confidence intervals (CIs). The primary outcomes were changes in systolic and diastolic BP. The secondary outcomes were changes in lipid profile, glucose metabolism, inflammatory markers for CVD, kidney and liver functions safety parameters. We assessed the data for risk of bias, heterogeneity, sensitivity, reporting bias and quality of evidence.ResultsFive trials were included involving 325 patients aged 18–80 years. Two trials involved high-income countries and three trials involved moderate-income countries. The analysis performed was based on three comparisons. No significant changes were found between systolic or diastolic blood pressure (BP) for the first comparison, 1,000 mg per day for a combined formulation of olive leaf extract versus a placebo. The second comparison, 500 mg per day of olive leaf extract versus placebo or no treatment, showed a significant reduction in systolic BP over a period of at least 8 weeks of follow up (MD −5.78 mmHg, 95% CI [−10.27 to −1.30]) and no significant changes on diastolic BP. The third comparison, 1,000 mg per day of olive leaf extract versus placebo shows no significant difference but an almost similar reduction in systolic BP (−11.5 mmHg in olive leaf extract and −13.7 mmHg in placebo, MD 2.2 mmHg, 95% CI [−0.43–4.83]) and diastolic BP (−4.8 mmHg in olive leaf extract and −6.4 mmHg in placebo, MD 1.60 mmHg, 95% CI [−0.13–3.33]). For secondary outcomes, 1,000 mg per day of olive leaf extract versus captopril showed a reduction in LDL (MD −6.00 mg/dl, 95% CI [−11.5 to −0.50]). The 500 mg per day olive leaf extract versus placebo showed a reduction in inflammatory markers for CVD IL-6 (MD −6.83 ng/L, 95% CI [−13.15 to −0.51]), IL-8 (MD −8.24 ng/L, 95% CI [−16.00 to −0.48) and TNF-alpha (MD −7.40 ng/L, 95% CI [−13.23 to −1.57]).ConclusionsThe results from this review suggest the reduction of systolic BP, LDL and inflammatory biomarkers, but it may not provide a robust conclusion regarding the effects of olive leaf extract on cardiometabolic profile due to the limited number of participants in the included trials.Review registrationsPROSPERO CDR 42020181212.

Olive Leaf Extract (OLE) impaired vasopressin-induced aquaporin-2 trafficking through the activation of the calcium-sensing receptor

Vasopressin (AVP) increases water permeability in the renal collecting duct through the regulation of aquaporin-2 (AQP2) trafficking. Several disorders, including hypertension and inappropriate antidiuretic hormone secretion (SIADH), are associated with abnormalities in water homeostasis. It has been shown that certain phytocompounds are beneficial to human health. Here, the effects of the Olive Leaf Extract (OLE) have been evaluated using in vitro and in vivo models. Confocal studies showed that OLE prevents the vasopressin induced AQP2 translocation to the plasma membrane in MCD4 cells and rat kidneys. Incubation with OLE decreases the AVP-dependent increase of the osmotic water permeability coefficient (Pf). To elucidate the possible effectors of OLE, intracellular calcium was evaluated. OLE increases the intracellular calcium through the activation of the Calcium Sensing Receptor (CaSR). NPS2143, a selective CaSR inhibitor, abolished the inhibitory effect of OLE on AVP-dependent water permeability. In vivo experiments revealed that treatment with OLE increases the expression of the CaSR mRNA and decreases AQP2 mRNA paralleled by an increase of the AQP2-targeting miRNA-137. Together, these findings suggest that OLE antagonizes vasopressin action through stimulation of the CaSR indicating that this extract may be beneficial to attenuate disorders characterized by abnormal CaSR signaling and affecting renal water reabsorption.

Effects of olive leaf extract (Olea europaea Leecino) on growth, haematological parameters, immune system and carcass composition in common carp (Cyprinus carpio)

In this study, the effects of olive leaf extract on growth, haematological parameters, immune system and carcass composition in common carp were examined. In this research, 180 common carp (32.26 ± 1.01 g) were randomly distributed to nine fibreglass tanks. The fish were fed a diet with 200 mg/kg olive leaf extract (group 1), 400 mg/kg olive leaf extract (group 2), and basal food (control group) for 75 days. At the end of the experiment, WG, SGR and PER values were significantly higher in the groups fed the diet containing 200 mg/kg of olive leaf extract compared with the control group. Furthermore, FCR and FER values were improved in the groups fed by diets with various levels of olive leaf extract than the control group. The contents of WBCs, lysozyme and NBT activity were significantly increased in the groups fed diets containing olive leaf extract. Cholesterol content was significantly lower in the group fed diet containing olive leaf extract compared with the control group. Also, serum triglyceride and carcass lipid contents were significantly lower in the group fed diet containing 200 mg/kg of olive leaf extract compared with the control group. Total protein, albumin, globulin and calcium contents were significantly higher in the group fed the diet containing 200 mg/kg of olive leaf extract compared with the control group. Our results demonstrated that diet containing 200 mg/kg olive leaf extract were efficient feed additives and has the potential for use in improving the growth performance and health status for this species.

Effects of olive leaf extract prepared in water on streptozotocin-induced oxidative stress and lipid peroxidation in rats

Bu çalışmada, Streptozotosin'in (STZ) neden olduğu diyabetik ratlarda su içinde hazırlanan zeytin yaprağı özütünün (OLE) antidiyabetik ve antioksidatif etkilerinin araştırması amaçlanmıştır. Çalışmamızda Atatürk Üniversitesi Tıbbi Uygulama ve Araştırma Merkezi (ATADEM)’den temin edilen ve ağırlıkları 200-215 g arasında değişen toplam 25 adet Albino Wistar erkek rat kullanıldı. Ratlar Kontrol, 0.5 g kg-1 OLE, 40 mg kg-1 STZ, 0.25 g kg-1 OLE + STZ ve 0.5 g kg-1 OLE + STZ olmak üzere beş gruba ayrıldı. 14 günlük OLE uygulama sonrası ratların karaciğer dokuları süperoksit dismutaz (SOD), glutatyon peroksidaz (GPx), glutatyon S-transferaz (GST) aktivitelerinin ve malondialdehit (MDA) seviyelerinin belirlenmesi için alındı. Kan örnekleri ise alanin transaminaz (ALT), aspartat transaminaz (AST) ve alkalen fosfataz (ALP) biyokimyasal parametrelerinin ve ek olarak glikoz seviyelerinin belirlenmesi için alındı. İstatistiksel analizler SPSS 20.0 yazılım programı kullanılarak ANOVA testi ile belirlendi. STZ ile birlikte OLE’nin iki farklı dozda oral yoldan verilmesinden sonra, diyabetik grup ile karşılaştırıldığında OLE’nin her iki doz grubunda ALP, ALT ve AST düzeylerinde önemli düşüşler gözlenmiştir (p&amp;lt;0.001). Ayrıca, sadece STZ verilen gruba kıyasla, STZ ile birlikte OLE uygulanan gruplarda SOD, GPx ve GST aktivitelerinde anlamlı bir artışla birlikte MDA, ALT, AST ve ALP düzeylerinde istatiksel olarak anlamlı düşüşler görülmüştür (p&amp;lt;0.001). Ancak OLE’nin 0.5 g kg-1 dozu 0.25 g kg-1 dozuna kıyasla daha etkili olmuştur. Sonuç olarak, elde edilen in-vivo veriler, suda hazırlanan OLE'nin oksidatif stresin kısıtlanması ve antioksidan aktivitelerin güçlendirilmesi sayesinde bir anti-diyabetik etkiye sahip olabileceğini göstermiştir.

Streptozotocin‐Induced Oxidative Stress in Rats: The Protective Role of Olive Leaf Extract

This paper investigates the antidiabetic and antioxidant effects of olive leaf extract (OLE) prepared in ethanol upon Streptozotocin (STZ)‐induced diabetic rats. The rats were divided into five groups (control, OLE, 40 mg/kg STZ, 0.25 g/kg OLE + STZ, and 0.5 g/kg OLE + STZ). The blood of rats was taken for determination of glucose levels besides oxidative activities (superoxide dismutase‐SOD, glutathione peroxidase‐GPx, glutathione‐S transferase‐GST activities, and malondialdehyde‐MDA) and biochemical parameters (alanine transaminase‐ALT, aspartate transaminase‐AST, and alkaline phosphatase‐ALP). While ALP, AST, ALT, and MDA levels showed an increase, SOD, GPx, and GST levels decreased in Group STZ compared to Control Group. When compared to the group given only STZ, OLE played a significant role in decreasing MDA, ALT, AST, and ALP levels, apart from increasing GPx, and GST following treatment of diabetic rats. As a result, the in vivo data obtained have shown that the OLE has an antidiabetic effect thanks to restricting oxidative stress and reinforcing antioxidant activities.

Olive Leaf Extract, from Olea europaea L., Reduces Palmitate-Induced Inflammation via Regulation of Murine Macrophages Polarization.

Olive tree (Olea europaea L.) leaves are an abundant source of bioactive compounds with several beneficial effects for human health. Recently, the effect of olive leaf extract in obesity has been studied. However, the molecular mechanism in preventing obesity-related inflammation has not been elucidated. Obesity is a state of chronic low-grade inflammation and is associated with an increase of pro-inflammatory M1 macrophages infiltration in the adipose tissue. In the current study, we explored Olea europaea L. leaf extract (OLE) anti-inflammatory activity using an in vitro model of obesity-induced inflammation obtained by stimulating murine macrophages RAW 264.7 with high dose of the free fatty acid palmitate. We found that OLE significantly suppressed the induction of pro-inflammatory mediators, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β, nitric oxide (NO), prostaglandin E2 (PGE2) and reactive oxygen species (ROS), while it enhanced the anti-inflammatory cytokine, IL-10. Moreover, we demonstrated that OLE reduced the oxidative stress induced by palmitate in macrophages by regulating the NF-E2-related factor 2 (NRF2)−Kelch-like ECH-associated protein 1 (KEAP1) pathway. Finally, we showed that OLE promoted the shift of M1 macrophage toward less inflammatory M2-cells via the modulation of the associated NF-κB and proliferator-activated receptor gamma (PPARγ) signaling pathways. Thereby, our findings shed light on the potential therapeutic feature of OLE in recovering obesity-associated inflammation via regulating M1/M2 status.

PENGARUH SEDIAAN DEKOK DAUN ZAITUN (Olea europaea L.) TERHADAP PENURUNAN TEKANAN DARAH PADA TIKUS PUTIH GALUR WISTAR (Rattus norvegicus strain wistar) JANTAN YANG DIINDUKSI NATRIUM KLORIDA 5,5%

According toWHOhypertension about 26.4% of world population who have suffered hypertension. It wouldprobably increase up to 29.2% in 2025. Usually,hypertension medical care uses convensional medicine, however itpossessessome side effects and could causecomplication.For that reason, herbal medicine is needed for safer andmore effective purpose. One of herbal medicines is olive leaf (Olea europea L).It aimed to figure out effect of oliveleaf extract (Olea europaea L.) on declining blood pressurein whitemale rat wistar strain (Rattus novergicus strainwistar) after 5.5% Natrium Chloride (NaCl) induction.24 of rats were divided into 4 groups of treatments and 5.5%NaCl inductions. Group I, as a control withaquadest treatment, Group II was inducted with 540 mgs of olive leafextract, Group III was inducted with 1080mgs of olive leaf extract, and Group IV was inducted with 2160 mgs ofolive leaf extract. Data were Analyzed byOne way ANOVA then followed with Post-hoc test using LeastSignificant Differences (LSD) test. From the group I, the mean of pretest was 117.83/150.83mmHg and the meanof post test was117.83/141.67 mmHg. Group II, the mean of pretest was 123.67/156,00 mmHg and the mean of posttest was87.00/116,00 mmHg. Group III, the mean of pretest was 123.50/156.83 mmHg and the mean of post testwasand the mean of post test was 81.67/112,50 mmHg. Group IV the mean of pretest was 119.00/156.50 mmHgandthe mean of post test was 80.00/105.00 mmHg.There were effects of olive leaf extract (Olea europaea L.) in 540mgs, 1080 mgs and 2160 mgs toblood pressure declining in white male rat wistar strain (Rattus novergicus strainwistar) after 5.5% NatriumChloride (NaCl) induction. The higest blood pressure declining was in Group IV of 2160mg olive leaf extractinduction.

The effect of olive leaf extract on cardiovascular health markers: a randomized placebo-controlled clinical trial

PurposeOverweight and obesity are associated with many health problems, including cardiovascular disease (CVD). Evidence from previous studies has shown that extracts from olive leaves rich in olive phenolics are able to positively affect CVD risk factors, such as high blood pressure and dyslipidemia. The aim of this study was to investigate the effect of 8-week olive leaf extract (OLE) administration on blood lipid profiles in overweight/obese subjects with mildly elevated cholesterol levels.MethodsIn this randomized, double-blind, placebo-controlled study, 77 healthy adult overweight/obese subjects (aged 56 ± 10 years and BMI 29.0 ± 2.7 kg/m2) with total cholesterol levels of 5.0–8.0 mmol/L (5.9 ± 0.7 mmol/L) were randomly assigned to receive 500 mg of OLE (n = 39) or placebo (n = 38) for 8 weeks. In total, 74 subjects completed the entire study protocol. At baseline, after 4 weeks, and after 8 weeks of supplementation, blood lipid profiles, oxidized low-density lipoprotein (oxLDL), blood pressure, glucose, and insulin levels were assessed. In addition, liver function parameters were measured at baseline and after 8 weeks.ResultsOLE supplementation did not significantly affect blood lipid levels after 4 weeks or after 8 weeks compared to placebo (all p > 0.05). For oxLDL, blood pressure, glucose, and insulin levels and liver function parameters, also no statistically significant differences were found between the two intervention groups (all p > 0.05).ConclusionsBlood lipid profiles were not significantly affected by 8 weeks OLE supplementation in overweight/obese subjects with mildly elevated cholesterol levels.Trial registeredThe trial has been registered at ClinicalTrials.gov (NCT02990637).

Study on the protective effect of hydroalcoholic Olive Leaf extract (oleuropein) on the testis and sperm parameters in adult male NMRI mice exposed to Mancozeb

This study aimed to assess the protective effects of the Olive Leaf Extract (OLE) against Mancozeb (MZB)-induced reproductive damage in male NMRI mice.In this experimental study, NMRI mice were randomly divided into 7 groups (n = 8) including 1: control, 2: MZB, 3: MZB + OLE (200 mg/kg), 4: MZB + OLE (400 mg/kg), 5: MZB + atropine (0.25 mg/kg), 6: OLE (200 mg/kg) and 7: OLE (400 mg/kg). Mice were sacrificed after 5 weeks, and blood samples were drawn to measure serum testosterone level. Sperm samples were collected and analyzed according to standard criteria. The left testis was removed to assess testicular parameters using H&E staining. The Protamine level and DNA fragmentation were determined by chromomycin A3 (CMA3) and SCD assays, respectively.Sperm viability decreased in MZB- induced groups. Also, the sperm's protamine deficiency (higher than 30%) and DNA fragmentation increased within MZB induced. There were significantly higher structural deformities of sperm's head, neck, and tail in MZB-treated groups as well (p < 0.05).Within treated groups with OLE, these sperm factors could repair defects versus MZB group. Furthermore, there were significant differences comparing sperm motility (type A, B, and D); protamine level, DNA fragmentation (SCD1, SCD3, and SCD4), and testosterone levels compared to the groups (p < 0.05). Sperm motility, seminiferous tubules diameter, the height of the germinal epithelium, and testosterone level within OLE 200 mg/kg was higher than other groups, while these factors in OLE 400 mg/kg was less than OLE 200 mg/kg.Results showed that oral administration of OLE could be useful in ameliorating MZB induced toxicity in the reproductive system of male mice within 200 mg/kg dosage; while OLE 400 mg/kg probably could exacerbate the harmful effects.

Olive Leaf Extract Modulates Quorum Sensing Genes and Biofilm Formation in Multi-Drug Resistant Pseudomonas aeruginosa.

Biofilm acts as a complex barrier against antibiotics. In this study, we investigated the inhibitory activities of Olea europaea (olive) leaves Camellia sinensis (green tea), Styrax benzoin, Ocimum basilicum, Humulus lupulus, Ruta graveolens, and Propolis extracts on the biofilm formation, pyocyanin production, and twitching motility of Pseudomonas aeruginosa isolates. Moreover, we investigated the effect of olive leaf extract on the transcription of some biofilm related genes. A total of 204 isolates of Pseudomonas were collected from different Egyptian hospitals. A susceptibility test, carried out using the disc diffusion method, revealed that 49% of the isolates were multidrug-resistant. More than 90% of the isolates were biofilm-forming, of which 26% were strong biofilm producers. At subinhibitory concentrations, green tea and olive leaf extracts had the highest biofilm inhibitory effects with 84.8% and 82.2%, respectively. The expression levels of lasI, lasR, rhlI, and rhlR treated with these extracts were significantly reduced (p < 0.05) by around 97–99% compared to untreated isolates. This study suggests the ability of olive leaf extract to reduce the biofilm formation and virulence factor production of P. aeruginosa through the down regulation of quorum sensing (QS) genes. This may help in reducing our dependence on antibiotics and to handle biofilm-related infections of opportunistic pathogens more efficiently.

Effects of Olive Leaf Extracts as Natural Preservative on Retailed Poultry Meat Quality.

Poultry meat is commonly marketed at refrigerated temperatures (2–5 °C). The major concern for retailers and consumers is the quality and safety of refrigerated poultry meat. During the chilling period, poultry meat undergoes too many undesirable changes due to microbial growth that leads to spoilage and economic loss. Therefore, this study was conducted to assess the effects of olive leaf extracts (OLE) used at three concentrations (0.25, 0.5, and 1%) on the sensory attributes, as well as the chemical and microbiological quality of raw poultry meat stored at 4 ± 1 °C for 15 days. The results revealed that the OLE addition reduced microbial growth successfully, and maintained the chemical quality and sensory attributes of poultry meat. Moreover, OLE extended the shelf-life of the poultry meat that held under proper refrigeration conditions up to 15 days compared to the control group, that was completely spoiled by the sixth day of storage. This study concludes that OLE could be used both as a natural antioxidant and an antimicrobial preservative for chilled poultry meat held at refrigerated temperature.

Dietary supplementation of olive leaf extract enhances growth performance, digestive enzyme activity and growth related genes expression in common carp Cyprinus carpio

It is not desirable to use synthetic chemicals as growth promoters in aquaculture. Therefore, phytogenic compounds have been extensively studied in fish diets due to their growth promoter effects. Common carp (Cyprinus carpio) is widely distributed around the world and has been reared in Asia for several centuries. This study was conducted to determine the effects of olive leaf extract (OLE) (0, 0.1, 0.25, 0.50 and 1%) on the growth performance, digestive enzyme activity in the intestine and the expression levels of some growth-related genes in the brain. liver, head kidney and mucsle tissue of common carp C. carpio. At the end of the 60-day feeding period, there was a significant increase in growth performance in the OLE0.1 and OLE0.25 groups. Similar trends have been obtained for digestive enzyme activities such as α-amylase, protease and lipase. Morover, the expression of growth hormone (GH) and insulin-like growth factor I (IGF-I) was regulated by OLE supplemented by up to 0.25% in brain, liver, head kidney and muscle tissue. This study confirms that dietary OLE may enhance the growth performance of the common carp by activating the digestive enzyme activity in the intestine and increase the expression of genes (GH and IGF-I) related with growth in brain, liver, head kidneys and muscle tissue of common carp up to use 0.10% in diets.