oleuropein and Disease-Models--Animal

In TgCRND8 (Tg) mice we checked the dose-response effect of diet supplementation with oleuropein aglycone (OLE) at 12.5 or 0.5 mg kg. Four month-old Tg mice were equally divided into four groups and treated for 8 weeks with a modified low fat (5.0%) AIN-76 A diet (10 g day. OLE supplementation at 12.5 mg kg. Our results extend previous data showing that the effects of OLE on behavioural performance and neuropathology are dose-dependent and not closely related to OLE by itself. In fact, diet supplementation with the same dose of a mix of polyphenols found in olive mill waste water resulted in comparable neuroprotection.

Topics: Amyloid beta-Peptides; Amyloid beta-Protein Precursor; Animals; Behavior, Animal; Brain; Cognitive Dysfunction; Dietary Supplements; Disease Models, Animal; Dose-Response Relationship, Drug; Iridoid Glucosides; Iridoids; Mice, Transgenic; Olea; Peptide Fragments; Plaque, Amyloid; Polyphenols; Wastewater

This study assesses whether oleuropein prevents ovalbumin (OVA)-induced food allergy (FA) and investigates the underlying mechanisms.. A Balb/c FA mouse model is established and maintained for 7 weeks. The subjects are administered OVA by oral gavage to induce FA and supplemented with different oleuropein doses (1.00-20.00 mg kg. These findings suggest that oleuropein prevents FA by enhancing intestinal epithelial barrier function and improving immune homeostasis and intestinal flora in sensitized mice. Therefore, diets rich in oleuropein should be recommended for people with FA.

Topics: Animals; Disease Models, Animal; Food Hypersensitivity; Gastrointestinal Microbiome; Immunoglobulin E; Intestinal Mucosa; Mice; Mice, Inbred BALB C; Ovalbumin

Acute lung injury (ALI) is one of the most common causes of death in diseases with septic shock. Oleuropein, one of the important components of olive leaf, has antioxidant and anti-inflammatory effects. The objective of this study was to investigate the effects of oleuropein on lipopolysaccharide (LPS)-induced ALI in rats. Oleuropein was administered to rats at a dose of 200 mg/kg for 20 days and LPS was given through intratracheal administration to induce ALI. The study was terminated after 12 h. The results showed that in the group treated with oleuropein, inflammatory cytokines and oxidative stress decreased in serum, bronchoalveolar lavage fluid (BALF), and lung tissue, and there were significant improvements in the picture of acute interstitial pneumonia (AIP) caused by LPS in histopathological examination. Based on the findings of the present study, oleuropein showed protective effects against LPS-induced ALI.

Topics: Acute Lung Injury; Animals; Anti-Inflammatory Agents; Antioxidants; Cytokines; Disease Models, Animal; Inflammation Mediators; Iridoid Glucosides; Lipopolysaccharides; Lung; Male; Neutrophil Infiltration; Oxidative Stress; Rats, Wistar

Neonatal hypoxia-ischemia (HI) causes white matter injury that is not fully prevented by therapeutic hypothermia. Adjuvant treatments are needed. We compared myelination in different piglet white matter regions. We then tested whether oleuropein (OLE) improves neuroprotection in 2- to 4-day-old piglets randomized to undergo HI or sham procedure and OLE or vehicle administration beginning at 15 minutes. All groups received overnight hypothermia and rewarming. Injury in the subcortical white matter, corpus callosum, internal capsule, putamen, and motor cortex gray matter was assessed 1 day later. At baseline, piglets had greater subcortical myelination than in corpus callosum. Hypothermic HI piglets had scant injury in putamen and cerebral cortex. However, hypothermia alone did not prevent the loss of subcortical myelinating oligodendrocytes or the reduction in subcortical myelin density after HI. Combining OLE with hypothermia improved post-HI subcortical white matter protection by preserving myelinating oligodendrocytes, myelin density, and oligodendrocyte markers. Corpus callosum and internal capsule showed little HI injury after hypothermia, and OLE accordingly had minimal effect. OLE did not affect putamen or motor cortex neuron counts. Thus, OLE combined with hypothermia protected subcortical white matter after HI. As an adjuvant to hypothermia, OLE may subacutely improve regional white matter protection after HI.

Topics: Animals; Animals, Newborn; Brain; Combined Modality Therapy; Disease Models, Animal; Hypothermia, Induced; Hypoxia-Ischemia, Brain; Iridoid Glucosides; Myelin Sheath; Neuroprotection; Neuroprotective Agents; Swine; White Matter

Obesity is a risk factor for development of metabolic diseases and cognitive decline; therefore, obesity prevention is of paramount importance. Neuronal mitochondrial dysfunction induced by oxidative stress is an important mechanism underlying cognitive decline. Olive leaf extract contains large amounts of oleanolic acid, a transmembrane G protein-coupled receptor 5 (TGR5) agonist, and oleuropein, an antioxidant. Activation of TGR5 results in enhanced mitochondrial biogenesis, which suggests that olive leaf extract may help prevent cognitive decline through its mitochondrial and antioxidant effects. Therefore, we investigated olive leaf extract's effects on obesity, cognitive decline, depression, and endurance exercise capacity in a mouse model. In physically inactive mice fed a high-fat diet, olive leaf extract administration suppressed increases in fat mass and body weight and prevented cognitive declines, specifically decreased working memory and depressive behaviors. Additionally, olive leaf extract increased endurance exercise capacity under atmospheric and hypoxic conditions. Our study suggests that these promising effects may be related to oleanolic acid's improvement of mitochondrial function and oleuropein's increase of antioxidant capacity.

Topics: Animals; Cognitive Dysfunction; Depression; Diet, High-Fat; Disease Models, Animal; Exercise Tolerance; Humans; Iridoid Glucosides; Male; Mice; Mitochondria; Obesity; Olea; Oleanolic Acid; Oxidative Stress; Physical Conditioning, Animal; Plant Extracts; Plant Leaves; Receptors, G-Protein-Coupled

Cerebral hypoxia-ischemia (HI) compromises the proteasome in a clinically relevant neonatal piglet model. Protecting and activating proteasomes could be an adjunct therapy to hypothermia. We investigated whether chymotrypsin-like proteasome activity differs regionally and developmentally in the neonatal brain. We also tested whether neonatal brain proteasomes can be modulated by oleuropein, an experimental pleiotropic neuroprotective drug, or by targeting a proteasome subunit gene using recombinant adeno-associated virus-9 (AAV). During post-HI hypothermia, we treated piglets with oleuropein, used AAV-short hairpin RNA (shRNA) to knock down proteasome activator 28γ (PA28γ), or enforced PA28γ using AAV-PA28γ with green fluorescent protein (GFP). Neonatal neocortex and subcortical white matter had greater proteasome activity than did liver and kidney. Neonatal white matter had higher proteasome activity than did juvenile white matter. Lower arterial pH 1 h after HI correlated with greater subsequent cortical proteasome activity. With increasing brain homogenate protein input into the assay, the initial proteasome activity increased only among shams, whereas HI increased total kinetic proteasome activity. OLE increased the initial neocortical proteasome activity after hypothermia. AAV drove GFP expression, and white matter PA28γ levels correlated with proteasome activity and subunit levels. However, AAV proteasome modulation varied. Thus, neonatal neocortical proteasomes can be pharmacologically activated. HI slows the initial proteasome performance, but then augments ongoing catalytic activity. AAV-mediated genetic manipulation in the piglet brain holds promise, though proteasome gene targeting requires further development.

Topics: Animals; Animals, Newborn; Blotting, Western; Brain; Disease Models, Animal; Hypothermia; Hypoxia-Ischemia, Brain; Iridoid Glucosides; Mice; Proteasome Endopeptidase Complex; Swine

When Zika virus emerged as a public health emergency there were no drugs or vaccines approved for its prevention or treatment. We used a high-throughput screen for Zika virus protease inhibitors to identify several inhibitors of Zika virus infection. We expressed the NS2B-NS3 Zika virus protease and conducted a biochemical screen for small-molecule inhibitors. A quantitative structure-activity relationship model was employed to virtually screen ∼138,000 compounds, which increased the identification of active compounds, while decreasing screening time and resources. Candidate inhibitors were validated in several viral infection assays. Small molecules with favorable clinical profiles, especially the five-lipoxygenase-activating protein inhibitor, MK-591, inhibited the Zika virus protease and infection in neural stem cells. Members of the tetracycline family of antibiotics were more potent inhibitors of Zika virus infection than the protease, suggesting they may have multiple mechanisms of action. The most potent tetracycline, methacycline, reduced the amount of Zika virus present in the brain and the severity of Zika virus-induced motor deficits in an immunocompetent mouse model. As Food and Drug Administration-approved drugs, the tetracyclines could be quickly translated to the clinic. The compounds identified through our screening paradigm have the potential to be used as prophylactics for patients traveling to endemic regions or for the treatment of the neurological complications of Zika virus infection.

Topics: Animals; Antiviral Agents; Artificial Intelligence; Chlorocebus aethiops; Disease Models, Animal; Drug Evaluation, Preclinical; High-Throughput Screening Assays; Immunocompetence; Inhibitory Concentration 50; Methacycline; Mice, Inbred C57BL; Protease Inhibitors; Quantitative Structure-Activity Relationship; Small Molecule Libraries; Vero Cells; Zika Virus; Zika Virus Infection

Depression is still one of challenging, and widely encountered disorders with complex etiology. The role of healthy diet and olive oil in ameliorating depression has been claimed. This study was designed to explore the effects of oleuropein; the main constituent of olive oil; on depression-like behaviors that are induced by repeated administration of corticosterone (40 mg/kg, i.p.), once a day for 21 days, in mice. Oleuropein (8, 16, and 32 mg/kg, i.p.) or fluoxetine (20 mg/kg, positive control, i.p.1) was administered 30 minutes prior to corticosterone injection. Sucrose consumption test, open-field test (OFT), tail suspension test (TST), and forced swimming test (FST) were performed. Reduced Glutathione (GSH), lipid peroxidation, and biogenic amines; serotonin, dopamine, and nor-epinephrine; levels were also analyzed in brain homogenates. Corticosterone treatment induced depression-like behaviors, it increased immobility time in the TST, OFT, and FST, decreased the number of movements in OFT, and decreased sucrose consumption. Corticosterone effect was associated with depletion of reduced glutathione and increase of lipid peroxidation, in addition to modification of biogenic amines; decreased serotonin and dopamine. Oleuropein or fluoxetine administration counteracted corticosterone-induced changes. In conclusion, oleuropein showed a promising antidepressant activity, that is evident by improving corticosterone-induced depression-like behaviors, and normalizing levels of biogenic amines.

Topics: Anhedonia; Animals; Behavior, Animal; Biogenic Amines; Brain; Corticosterone; Depression; Disease Models, Animal; Hindlimb Suspension; Immobilization; Iridoid Glucosides; Iridoids; Male; Mice; Movement; Neurotransmitter Agents; Oxidative Stress; Sucrose; Swimming

The antioxidant and cardioprotective effects of oleuropein have been reported in several studies; however, its effect on ketamine cardiotoxicity has not been known yet. The aim of this study was to investigate the effects of oleuropein in ketamine-induced cardiotoxicity model in rats. A total of 28 male Wistar Albino rats were included in the study and they were randomly divided into four groups, each having seven rats. Group 1 (control): rats were given 1 mL of DMSO by oral gavage method for 7 days. Group 2 (ketamine): on the seventh day of the study, 60 mg/kg ketamine was administered intraperitoneally. Then, 60 mg/kg ketamine was administered intraperitoneally every 10 min for 3 h. Group 3 (oleuropein): rats were given 200 mg/kg/day oleuropein by oral gavage method for 7 days. Group 4 (oleuropein + ketamine): rats were given 1 × 200 mg/kg oleuropein by oral gavage method for 7 days. Furthermore, 60 mg/kg ketamine was administered intraperitoneally on the seventh day of the experiment. Then, 60 mg/kg ketamine was administered intraperitoneally every 10 min for 3 h. Serum cardiac marker (TnI, CK-MB and CK) levels were measured. Histopathological analysis was performed on a portion of the cardiac tissue. Cardiac tissue oxidative stress and antioxidant markers (MDA, GSH, GSH.Px and CAT), TNF-α, IL-6, NF-κB, COX-2 and Nrf-2 gene expressions, and protein conversion levels of related genes were determined. Data obtained showed that ketamine administration increased MDA (p < 0.001), TNF-α (p < 0.01), IL-6 (p < 0.01), COX-2 (p < 0.001) and NF-κB (p < 0.001) levels, as well as serum TnI (p < 0.001), CK-MB (p < 0.001) and CK (p < 0.01) levels whereas decreased GSH (p < 0.05) and Nrf-2 (p < 0.05) levels, as well as GSH-Px (p < 0.001) and CAT (p < 0.05) enzyme activities. Oleuropein administration was observed to decrease MDA, TNF-α, IL-6, COX-2, NF-κB, TnI, CK-MB and CK levels close to the control group and to increase GSH levels and GSH-Px and CAT enzyme activities close to the control group. This study showed that oleuropein administration reversed the increased oxidative stress and inflammation as a result of the use of ketamine and had protective effects on the heart.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Cardiotoxicity; Disease Models, Animal; Heart Diseases; Inflammation Mediators; Iridoid Glucosides; Ketamine; Male; Myocytes, Cardiac; Oxidative Stress; Rats, Wistar; Signal Transduction

Inflammation and oxidative stress pathways have emerged as novel targets in the management of inflammatory bowel diseases (IBD). Targeting the drug to the inflamed colon remains a challenge. Nanostructured lipid carriers (NLCs) have been reported to accumulate in inflamed colonic mucosa. The antioxidant/antiinflamatory polyphenol oleuropein (OLE) was loaded in NLCs (NLC-OLE). NLC-OLE showed to be more effective in decreasing the TNF-α secretion and intracellular reactive oxygen species (ROS) by activated macrophages (J774) compared to the conventional form of OLE. OLE efficacy was preserved within NLC-OLE ameliorating inflammation in a murine model of acute colitis: reduced levels of TNF-α and IL-6, decreased neutrophil infiltration and improved histopathology of the colon were reported. In addition, NLC-OLE enhanced the ROS scavenging activity of OLE in the colon after oral administration. These data suggest that the proposed NLC-OLE could be a promising drug delivery system for OLE in IBD treatment.

Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Antioxidants; Cell Line; Colitis; Disease Models, Animal; Drug Carriers; Drug Delivery Systems; Inflammation; Iridoid Glucosides; Iridoids; Lipids; Macrophages; Male; Mice; Mice, Inbred C57BL; Nanostructures; Oxidative Stress; Reactive Oxygen Species

Topics: Animals; Dietary Supplements; Disease Models, Animal; Heme Oxygenase-1; Inflammasomes; Iridoid Glucosides; Iridoids; Janus Kinases; Kidney; Lupus Nephritis; MAP Kinase Signaling System; Matrix Metalloproteinase 3; Membrane Proteins; Mice, Inbred BALB C; NF-kappa B; Nitric Oxide Synthase Type II; NLR Family, Pyrin Domain-Containing 3 Protein; STAT Transcription Factors; Terpenes

This study aims to develop and evaluate oleuropein loaded surface functionalized folate-targeted - PEG liposomes for the effective management of prostate cancer in an animal model.. Film hydration-cum-extrusion technique was used to produce liposomes. Particle size, entrapment efficiency, drug loading, electron microscopy, and drug release study were performed for the characterization. Cell viability and various in vitro studies (phosphatidylserine internalization, TUNEL assay, measurement of mitochondrial membrane potential and caspase-3 assay) were performed to compare the anticancer and apoptotic effects of developed liposomes against the plain oleuropein. Comparative pharmacokinetic profiling and anticancer efficacy studies including a change in tumor volume, body weight, and survival analysis were performed in mice model.. The developed liposomes (OL-FML) showed the particle size of 184.2 ± 9.16 nm, the zeta potential of 1.41 ± 0.24 mV, entrapment efficiency of 63.52 ± 4.15% and drug loading of 21.31 ± 2.37%. OL-FML showed higher in vitro anti-proliferative effect and apoptosis on 22Rv1 cells. In vivo pharmacokinetic study revealed a nearly 6 fold increase in the bioavailability of OL-FML (AUC. The study provides conclusive evidence for the utilization of combining passive and active targeting strategy to enhance the anticancer effect of OL.

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Cell Survival; Disease Models, Animal; Drug Liberation; Folic Acid; Humans; Iridoid Glucosides; Iridoids; Liposomes; Male; Mice; Mice, Inbred BALB C; Particle Size; Prostatic Neoplasms

Post-traumatic stress disorder (PTSD) is a condition that develops after an individual has experienced a major trauma. This psychopathological response to traumatic stressors induces learning and memory deficits in rats. Oleuropein (OLE), a major compound in olive leaves, has been reported to possess several pharmacological properties, including anti-cancer, anti-diabetic, anti-atherosclerotic and neuroprotective activities. However, the cognitive effects of OLE and its mechanism of action have remained unclear in PTSD. In this study, we examined whether OLE improved spatial cognitive impairment induced in rats following single prolonged stress (SPS), an animal model of PTSD. Male rats were treated intraperitoneally (i.p.) with vehicle or various doses of OLE for 14 consecutive days after the SPS procedure. The SPS procedure resulted in cognitive impairment in the object recognition task and the Morris water maze test, which was reversed by OLE (100 mg/kg, i.p). Additionally, as assessed by immunohistochemistry and reverse transcription-polymerase chain reaction analysis, the administration of OLE significantly alleviated memory-associated decreases in the levels of brain-derived neurotrophic factor and cAMP response element-binding protein and mRNA in the hippocampus. Together, these findings suggest that OLE attenuated SPS-induced cognitive impairment significantly by inhibiting the expression of pro-inflammatory mediators in the rat brain. Thus, OLE reversed several behavioral impairments triggered by the traumatic stress of SPS and might be a potential useful therapeutic intervention for PTSD.

Topics: Animals; Brain-Derived Neurotrophic Factor; Cognition; Cytokines; Disease Models, Animal; Hippocampus; Iridoid Glucosides; Iridoids; Male; Rats; Rats, Sprague-Dawley; Stress Disorders, Post-Traumatic; Vasodilator Agents

Hepatotoxicity induced by cyclophosphamide (Cyclo) is a major concern in clinical practice. This study was designed to investigate the possible cytoprotective effect of natural antioxidants as oleuropein and quercetin against Cyclo induced hepatotoxicity via the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway. Male Wistar rats were randomly divided into six groups and treated for 10 days as follow: Group I (Normal control) received saline, group II (Oleu control): received orally oleuropein 30 mg/kg/day, group III (Quer control): administered orally quercetin 50 mg/kg/day, group IV (Cyclo): received saline and injected with single intraperitoneal (i.p) dose of Cyclo 200 mg/kg at day 5, group V (Oleu ttt): treated with oleuropein plus Cyclo i.p. injection at day 5, and group VI (Quer ttt): treated with quercetin plus Cyclo i.p. injection at day 5. Injection of Cyclo showed marked increase in serum transaminases and alkaline phosphatase, hepatic malondialdehyde (MDA) and tumor necrosis factor-alpha (TNF-⍺) levels along with significant reduction in hepatic reduced glutathione (GSH), superoxide dismutase (SOD), and catalase levels in addition to downregulation of hepatic Nrf2 and HO-1 expressions and reduction in hepatic nuclear Nrf2 binding activity when compared with normal group. Histopathological examination of Cyclo treated rats revealed hepatic damage. Both oleuropein and quercetin exhibited an improvement in the biochemical and histopathological findings. In conclusion, the natural antioxidants oleuropein and quercetin counteract the Cyclo induced hepatotoxicity through activation of Nrf2/HO-1 signaling pathway with subsequent suppression of oxidative stress and inflammation.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Biological Products; Chemical and Drug Induced Liver Injury; Cyclophosphamide; Disease Models, Animal; Heme Oxygenase-1; Humans; Iridoid Glucosides; Iridoids; Liver; Male; NF-E2-Related Factor 2; Oxidative Stress; Quercetin; Rats; Rats, Wistar; Signal Transduction

BACKGROUND In this study, we investigated the potential neuroprotective effect of oleuropein (OLE) on apoptotic changes via modulating Akt/glycogen synthase kinase 3 beta (Akt/GSK-3b) signaling in a rat model of cerebral ischemia/reperfusion injury (IRI). MATERIAL AND METHODS Sprague-Dawley male rats (12 weeks, n=200) were randomly assigned to 5 groups: sham group, vehicle (IRI+ vehicle) group, OLE (IRI+OLE) group, OLE+LY294002 (IRI+OLE+LY294002) group, and LY294002(IRI+LY294002) group. The rats were subjected to cerebral ischemia/reperfusion injury (IRI) model and treated once daily for 5 days with vehicle and OLE (100 mg/kg via intraperitoneal injection) after IRI injury. LY294002 (0.3 mg/kg) was intraperitoneally injected once at 30 min after IRI injury. Brain edema, neurological deficit, rotarod latencies, and Morris water maze (MWM) performance were evaluated after IRI. The number of dead cells were assayed by TUNEL staining. Western blot was used to detect the expression of Bcl-2, Bax, cleaved caspase-3 (CC3), neurotrophic factors, and the phosphorylation levels of Akt and GSK-3β. RESULTS Compared with the vehicle group, brain water content, neurological deficits, rotarod latencies, and escape latency following IRI were reduced in the OLE group. Cell apoptosis and reduced neurotrophic factor caused by IRI was also attenuated by OLE. Furthermore, increased p-Akt and decreased p-GSK-3β were caused by OLE, which were associated with decrease of Bax/Bcl-2 ratio and the suppression of Caspase-3 activity after IRI. Importantly, all the beneficial effects of OLE in the vehicle group were abrogated by PI3K inhibitor LY294002. CONCLUSIONS Cerebral ischemia was protected by OLE via suppressing apoptosis through the Akt/GSK-3β pathway and upregulating neurotrophic factor after IRI.

Topics: Animals; Apoptosis; Brain; Brain Ischemia; Disease Models, Animal; Glycogen Synthase Kinase 3 beta; Infarction, Middle Cerebral Artery; Iridoid Glucosides; Iridoids; Male; Neurons; Neuroprotective Agents; Oncogene Protein v-akt; Phosphatidylinositol 3-Kinases; Phosphorylation; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Signal Transduction

Oleuropein mediates most of the beneficial effects of olive products. This study examined the role of oxidative stress in the effects of oleuropein on lipid profile and blood glucose in rats with simultaneous renovascular hypertension and type 2 diabetes. Eight groups (n = 7-9 each) of male Sprague-Dawley rats including a control, a type 2 diabetic, a renovascular hypertensive, a sham, a simultaneously hypertensive diabetic receiving vehicle, and 3 simultaneously hypertensive-diabetic receiving 20, 40, or 60 mg/kg/day oleuropein were used. Four weeks after treatment, blood glucose, lipid profile, and biomarkers of oxidative stress were measured, and glucose tolerance test (GTT) was performed. Simultaneously hypertensive diabetic rats had significantly higher blood pressure, blood glucose, and serum total cholesterol, low-density lipoprotein cholesterol (LDL-C), triglyceride and malondialdehyde. They also had lower serum high-density lipoprotein cholesterol, erythrocyte superoxide dismutase, and impaired glucose tolerance. Oleuropein significantly reduced blood pressure, blood glucose, and serum total cholesterol, LDL-C, triglyceride and malondoaldehyde. It also increased serum high-density lipoprotein cholesterol, erythrocyte superoxide dismutase, and improved glucose tolerance. The findings show that the model is associated with impaired glucose tolerance, and adverse lipid profile. They also show that oleuropein, partly by an antioxidant mechanism, improves glucose tolerance and changed lipid profile favorably.

Topics: Animals; Antioxidants; Blood Glucose; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Disease Models, Animal; Glucose Tolerance Test; Hypertension, Renal; Hypertension, Renovascular; Iridoid Glucosides; Iridoids; Lipids; Male; Malondialdehyde; Molecular Structure; Oxidative Stress; Rats; Rats, Sprague-Dawley; Streptozocin; Superoxide Dismutase

Oleuropein (OLE) is a natural secoiridoid that is derived from Olea europaea. OLE possesses cardioprotective effects in experimental models of hypertension, myocardial infarction, atherosclerosis and hyperlipidaemia. In the present study, the effects of OLE on experimental autoimmune myocarditis (EAM) were evaluated. EAM in rats were induced by subcutaneous injections of porcine cardiac myosin. Cardiac function parameters, myocardial pathology, myocardial inflammatory cell infiltration and nuclear factor kappa-B (NF-κB) expression were measured. Our data showed that the postmyocarditis rats exhibited increased left ventricular end systolic diameters, left ventricular end diastolic diameters, left ventricular end-diastolic pressures (LVEDP), and decreased ejection fractions. However, OLE significantly suppressed these changes in EAM rats. Histological analysis revealed that myosin induced miliary foci of discolouration on endocardial surfaces and extensive myocardial injuries with inflammatory cell infiltration were significantly improved by OLE therapy. A definitive positive correlation between the histological scores and LVEDP was observed. Moreover, OLE inhibited CD4

Topics: Animals; Autoimmune Diseases; Cardiac Myosins; Cardiotonic Agents; Cytokines; Disease Models, Animal; Iridoid Glucosides; Iridoids; Male; Mitogen-Activated Protein Kinases; Myocarditis; Myocardium; NF-kappa B; Rats, Inbred Lew; Signal Transduction; T-Lymphocytes; Ventricular Function, Left

The purpose of this study was the evaluation of the antioxidant activity of natural and semisynthetic polyphenol derivatives from Olea europea L., by assessing malondialdehyde (MDA), an important marker of oxidative stress.. Polyphenol as hydroxytyrosol, oleuropein, oleuropein aglycone as mix of four tautomeric forms and their respective acetyl-derivatives were obtained from olive leaves using semisynthetic protocols. These compounds were administered intraperitoneally to Wistar rats treated with paraquat, an herbicide which is able to cause oxidative stress after central administration. Malondialdehyde was derivatized with 2,4-dinitrophenylhydrazine to produce hydrazone that was purified by solid-phase extraction. Using high-performance liquid chromatography coupled with a diode array, free and total MDA was measured on homogenate rat brain as marker of lipid peroxidation. The analytical method was fully validated and showed linearity in the tested concentration range, with detection limit of 5 ng/ml. Recovery ranged from 94.1 to 105.8%.. Both natural and semisynthetic polyphenol derivatives from a natural source as olive leaves were able to reduce MDA detection. The more lipophilic acetyl-derivatives showed an antioxidant activity greater than parent compounds. This potency seems to put in evidence a strict correlation between lipophilicity and bioavailability.

Topics: Animals; Antioxidants; Brain; Chromatography, High Pressure Liquid; Disease Models, Animal; Iridoid Glucosides; Iridoids; Limit of Detection; Lipid Peroxidation; Male; Malondialdehyde; Olea; Oxidative Stress; Plant Extracts; Plant Leaves; Polyphenols; Rats; Rats, Wistar

Intracerebral haemorrhage (ICH) as a devastating form of stroke has remained a public health threat due to lack of FDA-approved therapy. Oxidative stress originated from blood cell degradation products plays a crucial role in the ICH pathogenesis. In this study we evaluated oleuropein, a potent natural antioxidant from olive, in a well-established rat ICH model from overall symptoms to detailed molecular mechanism.. ICH model was established by collagenase injection to the brain of rats, which were randomly divided into groups with vehicle mock treatment, followed by treatment with different doses of oleuropein via daily intraperitoneal injection post-ICH for 3days. The overall neurological deficit, brain edema level and blood-brain barrier (BBB) integrity were then measured in different treatment groups. To understand the protection mechanism of oleuropein in ICH, BBB structural components ZO-1 and occludin, oxidative stress and MAPK signalling pathways were also examined.. Oleuropein treatment showed overall alleviation of ICH-associated neurological deficit and brain edema in a dose dependent manner. Consistently, it could preserve the BBB structure and attenuate oxidative stress as well as ICH-induced MAPK activation in brain tissue.. Our study suggests oleuropein could be used as a promising therapeutic agent for ICH.

Topics: Animals; Antioxidants; Blood-Brain Barrier; Brain Edema; Cerebral Hemorrhage; Disease Models, Animal; Dose-Response Relationship, Drug; Injections, Intraperitoneal; Iridoid Glucosides; Iridoids; Male; MAP Kinase Signaling System; Oxidative Stress; Rats; Rats, Sprague-Dawley; Stroke

Much of the beneficial effects of olive products have been attributed to oleuropein. This study examined the effects of oleuropein in rats with heart failure induced by permanent ligation of left coronary arteries. Twenty-four hours after the operation, the rats were assigned to five groups including a sham assigned to receive vehicle (1 ml/day) and four coronary ligated groups assigned to receive vehicle or oleuropein at 5, 10, or 20 mg/kg/day. Five weeks later, echocardiographic and hemodynamic parameters, serum concentrations of oxidative stress, and inflammatory markers were determined. Myocardial infarction group receiving vehicle showed impaired hemodynamic and echocardiographic parameters as evidenced by decreased left ventricular systolic pressure, rate of rise and decrease of left ventricular pressure, stroke volume, ejection fraction, and cardiac output. In addition, significant reduction in superoxide dismutase and glutathione reductase was observed. Oleuropein treatment prevented the reduction of these variables. Moreover, the group had a significantly higher infarct size and serum malondialdehyde, interleukin-1β, and tumor necrosis factor-α than those of the sham group. Treatment with oleuropein prevented the increase of these variables. The results show that oleuropein attenuates the progression of heart failure, possibly by antioxidative and antiinflammatory effects.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Biomarkers; Disease Models, Animal; Disease Progression; Glutathione Reductase; Heart Failure; Hemodynamics; Inflammation Mediators; Interleukin-1beta; Iridoid Glucosides; Iridoids; Male; Malondialdehyde; Myocardial Infarction; Oxidative Stress; Rats, Sprague-Dawley; Superoxide Dismutase; Tumor Necrosis Factor-alpha; Ventricular Function, Left

Oleuropein, a well-known olive polyphenol, has been shown to mediate neuroprotection in Alzheimer's disease and cerebral ischemia. We investigated the effects of oleuropein on pentylenetetrazole (PTZ)-induced seizures in male NMRI mice, with diazepam as the standard drug. We also examined the possible involvement of opioidergic/nitrergic pathways in the probable effects of oleuropein. Intraperitoneal (i.p.) administration of different doses of oleuropein (10, 20 and 30 mg/kg) significantly increased the seizure threshold 60 min prior to induction of seizure, in a dose-dependent manner. Administration of naltrexone (10 mg/kg, i.p.), an opioid receptor antagonist, completely reversed the anticonvulsant effects of oleuropein (10 mg/kg). On the other hand, the anticonvulsant effect of oleuropein (10 mg/kg) was blocked by a non-effective dose of nonspecific inhibitor of nitric oxide synthase (NOS), L-NAME (1 and 10 mg/kg, i.p) and a selective inhibitor of neuronal NOS, 7-nitroindazole (30 mg/kg, i.p.). However, the nitric oxide precursor, L-arginine (30 and 60 mg/kg, i.p.) potentiated the anticonvulsant activity of oleuropein (10 mg/kg). A selective inducible NOS inhibitor, aminoguanidine (100 mg/kg, i.p.) did not change the anticonvulsant activity of oleuropein. It seems that the opioidergic system and constitutive neuronal NOS may be involved in the anticonvulsant properties of oleuropein.

Topics: Animals; Biological Products; Disease Models, Animal; Dose-Response Relationship, Drug; Iridoid Glucosides; Iridoids; Male; Mice; Olea; Pentylenetetrazole; Seizures

Hemorrhagic cystitis is one of the devastating complications seen after receiving cyclophosphamide chemotherapy. Oleuropein is the most important phenolic compound of olive leaves that mediates most of its beneficial pharmacological properties. Herein, we investigated the possible uroprotective effect of oleuropein against cyclophosphamide induced hemorrhagic cystitis in a rat model. For this purpose, we measured bladder nitric oxide, reduced glutathione, catalase, tumor necrosis factor-alpha and vascular endothelial growth factor levels in addition to the bladder gene expression of intercellular adhesion molecule-1 after induction of hemorrhagic cystitis in the presence or absence of oleuropein. Histopathological examination of bladder tissues was also performed. After cyclophosphamide injection, we demonstrated a significant decrease in bladder reduced glutathione (39%) and catalase (55.4%) levels and a significant increase of nitric oxide (5.6 folds), tumor necrosis factor-alpha (3.3 folds), vascular endothelial growth factor (2 folds) and intercellular adhesion molecule-1 (8 folds) bladder contents when compared to those in normal control rats. Administration of oleuropein induced a marked elevation in bladder reduced glutathione (37.8%), catalase (100.4%) with a prominent reduction of bladder nitric oxide (40%), tumor necrosis factor-alpha (35.9%) and vascular endothelial growth factor (56.2%) levels along with downregulation of intercellular adhesion molecule-1 bladder expression (73.1%) in comparison to cyclophosphamide treated rats levels. Our data demonstrated that oleuropein counteracts the harmful effects of cyclophosphamide on the bladder through its antioxidant and anti-inflammatory activities. Oleuropein exerts a definite uroprotective effect against cyclophosphamide induced hemorrhagic cystitis in rats.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Cyclophosphamide; Cystitis; Disease Models, Animal; Gene Expression Regulation; Hemorrhage; Humans; Intercellular Adhesion Molecule-1; Iridoid Glucosides; Iridoids; Male; Rats; Rats, Sprague-Dawley; Real-Time Polymerase Chain Reaction; Urinary Bladder

Myocardial infarction causes a cascade of events, which leads to heart failure, debilitation and death. This study examined possible cardioprotective effect of oleuropein in rats with acute myocardial infarction. Male Sprague-Dawly rats were allocated to five groups: sham, myocardial infarction receiving vehicle, and three myocardial infarction receiving oleuropein at 10, 20, and 30 mg/kg/day for 7 days, and underwent sham operation or coronary ligation. Twenty-four hours later, animals underwent echocardiographic and hemodynamic studies, and infarct areas, serum concentrations of oxidative stress and inflammatory markers were determined. Myocardial infarction group receiving vehicle had significantly lower left ventricular developed and systolic pressures, rate of rise/decrease of left ventricular pressure, stroke volume, ejection fraction and cardiac output, and serum superoxide dismutase and glutathione reductase than those of sham group. Pretreatment with oleuropein prevented the reduction of these variables. Moreover, the group had a significantly higher serum malondialdehyde, interleukin-1β, TNF-α, creatin kinase-MB, and troponin I, lactate dehydrogenase, and infarct area than those of sham group. Pretreatment with oleuropein prevented the increase of these variables. The findings indicate that coronary ligation results in acute myocardial infarction characterized by impaired cardiac function, and oleuropein pretreatment prevented cardiac impairment partly by reducing oxidative stress and release of proinflammatory cytokines.

Topics: Animals; Biomarkers; Cardiotonic Agents; Creatine Kinase, MB Form; Disease Models, Animal; Electrocardiography; Hemodynamics; Interleukin-1beta; Iridoid Glucosides; Iridoids; L-Lactate Dehydrogenase; Male; Malondialdehyde; Myocardial Infarction; Oxidative Stress; Rats; Rats, Sprague-Dawley; Troponin I; Tumor Necrosis Factor-alpha; Ultrasonography; Vasodilator Agents

Ischemic preconditioning, which is mediated by cell signaling molecules, protects the heart from ischemia-reperfusion injury by limiting the infarct size. Oleuropein, the main polyphenolic constituent of olives, reduced the infarct size in normal and cholesterol-fed rabbits when it was administered at a nutritional dose. The aim of the present study was to compare the effects of oleuropein and preconditioning in terms of the cell signaling and metabolism pathways underlying myocardial protection. Rabbits were randomly divided into six groups: the control group received 5 % dextrose for six weeks, the preconditioning group was subjected to two cycles of preconditioning with 5 min ischemia/10 min reperfusion, the O6 group was treated with oleuropein for six weeks, the Chol group was fed a cholesterol-enriched diet and 5 % dextrose for six weeks, and the CholO6 and CholO3 groups were treated with cholesterol and oleuropein for six and three weeks, respectively; oleuropein was dissolved in 5 % dextrose solution and was administered orally at a dose of 20 mg × kg(-1) × day(-1). All animals were subsequently subjected to 30 min myocardial ischemia followed by 10 min of reperfusion. At that time, myocardial biopsies were taken from the ischemic areas for the assessment of oxidative and nitrosative stress biomarkers (malondialdehyde and nitrotyrosine), and determination of phosphorylation of signaling molecules involved in the mechanism of preconditioning (PI3K, Akt, eNOS, AMPK, STAT3). The tissue extracts NMR metabolic profile was recorded and further analyzed by multivariate statistics. Oxidative biomarkers were significantly reduced in the O6, CholO6, and CholO3 groups compared to the control, preconditioning, and Chol groups. Considering the underlying signaling cascade, the phosphorylation of PI3K, Akt, eNOS, AMPK, and STAT-3 was significantly higher in the preconditioning and all oleuropein-treated groups compared to the control and Chol groups. The NMR-based metabonomic study, performed through the analysis of spectroscopic data, depicted differences in the metabolome of the various groups with significant alterations in purine metabolism. In conclusion, the addition of oleuropein to a normal or hypercholesterolemic diet results in a preconditioning-like intracellular effect, eliminating the deleterious consequences of ischemia and hypercholesterolemia, followed by a decrease of oxidative stress biomarkers. This effect is exerted through inducing precondit

Topics: Animals; Cholesterol; Disease Models, Animal; Hypercholesterolemia; Iridoid Glucosides; Iridoids; Male; Malondialdehyde; Myocardial Ischemia; Myocardial Reperfusion Injury; Myocardium; Olea; Oxidative Stress; Phosphatidylinositol 3-Kinases; Protective Agents; Rabbits; Signal Transduction; Tyrosine

Oleuropein, a phenolic compound found in abundance in olive leaves, has beneficial effects on various diseases. However, it is unknown whether an oleuropein-rich diet is efficacious against type 2 diabetic phenotypes. In this study, we investigated the effects of the oleuropein-containing supplement OPIACE, whose oleuropein content exceeds 35% (w/w), on the diabetic phenotypes in type 2 diabetes model Tsumura Suzuki Obese Diabetes (TSOD) mouse. TSOD mice were fed OPIACE at 4 weeks of age, i.e., before the TSOD mice exhibited diabetic phenotypes. We revealed that OPIACE attenuated hyperglycemia and impaired glucose tolerance in TSOD mice over the long-term (from 10 to 24 weeks of age) but had no effect on obesity. Furthermore, we demonstrated that OPIACE mildly reduced oxidative stress in TSOD mice by 26.2% and attenuated anxiety-like behavioral abnormality in aged TSOD mice. The results suggest that oleuropein suppresses the progression of type 2 diabetes and diabetes-related behavioral abnormality over the long-term.

Topics: Animals; Blood Glucose; Diabetes Mellitus, Type 2; Diet; Disease Models, Animal; Glucose Tolerance Test; Humans; Hyperglycemia; Iridoid Glucosides; Iridoids; Male; Mice; Mice, Obese

The healthy effects of plant polyphenols, some of which characterize the so-called Mediterranean diet, have been shown to arise from epigenetic and biological modifications resulting, among others, in autophagy stimulation. Our previous work highlighted the beneficial effects of oleuropein aglycone (OLE), the main polyphenol found in the extra virgin olive oil, against neurodegeneration both in cultured cells and in model organisms, focusing, in particular, autophagy activation. In this study we investigated more in depth the molecular and cellular mechanisms of autophagy induction by OLE using cultured neuroblastoma cells and an OLE-fed mouse model of amylod beta (Aβ) deposition. We found that OLE triggers autophagy in cultured cells through the Ca2+-CAMKKβ-AMPK axis. In particular, in these cells OLE induces a rapid release of Ca2+ from the SR stores which, in turn, activates CAMKKβ, with subsequent phosphorylation and activation of AMPK. The link between AMPK activation and mTOR inhibition was shown in the OLE-fed animal model in which we found that decreased phospho-mTOR immunoreactivity and phosphorylated mTOR substrate p70 S6K levels match enhanced phospho-AMPK levels, supporting the idea that autophagy activation by OLE proceeds through mTOR inhibition. Our results agree with those reported for other plant polyphenols, suggesting a shared molecular mechanism underlying the healthy effects of these substances against ageing, neurodegeneration, cancer, diabetes and other diseases implying autophagy dysfunction.

Topics: AMP-Activated Protein Kinases; Animals; Autophagy; Disease Models, Animal; Humans; Iridoid Glucosides; Iridoids; Mice; Signal Transduction; TOR Serine-Threonine Kinases

Translational research needs valid animal models of disease to discover new pathogenetic aspects and treatments. In Alzheimer's disease (AD), transgenic models are of great value for AD research and drug testing.. It was the aim of this study to analyze the power of dietary polyphenols against neurodegeneration by investigating the effects of oleuropein aglycone (OLE), the main phenol in the extra virgin olive oil (EVOO), a key component of the Mediterranean diet (MD), in a mouse model of amyloid-β deposition.. TgCRND8 mice (3.5 months old), expressing the mutant KM670/671NL+V717F h-βAPP695 transgene, and wild-type (wt) mice were used to study in vivo the effects of an 8-week dietary supplementation with OLE (50 mg/kg of diet) [Grossi et al: PLoS One 2013;8:e71702], following the European Communities Council Directive 86/609 (DL 116/92) and National Guidelines (permit number: 283/2012-B).. OLE administration ameliorates memory dysfunction, raises a significant autophagic response in the cortex and promotes the proliferation of newborn cells in the subgranular zone of the dentate gyrus of the hippocampus.. Our findings support the beneficial effects of EVOO and highlight the possibility that continuous intake of high doses of OLE, both as a nutraceutical or as a food integrator, may prevent/delay the appearance of AD and reduce the severity of its symptoms.

Topics: Alzheimer Disease; Animal Feed; Animals; Brain; Diet, Mediterranean; Disease Models, Animal; Humans; Iridoid Glucosides; Iridoids; Mice, Transgenic; Neuroprotective Agents; Olive Oil; Plant Oils; Translational Research, Biomedical

The mechanism of oleuropein's antihypertensive effects was examined in rat model of simultaneous type 2 diabetes and renal hypertension (diabetic hypertensive). Five groups of male Sprague-Dawley rats including a control, a diabetic-hypertensive group receiving vehicle, and three diabetic-hypertensive groups receiving oleuropein at 20, 40, or 60 mg/kg/day were used. The duration of diabetes was 10 weeks; during the last 4 weeks of which, animals were hypertensive and received vehicle or oleuropein. Systolic blood pressure, glucose and malondialdehyde, heart rate, and maximal response to phenylephrine (PE) in the absence of nitro-L-arginine methyl ester (L-NAME) of oleuropein-treated groups were significantly lower than those of vehicle-treated group. Erythrocyte superoxide dismutase, maximal response to PE in the presence of L-NAME, and maximal response to acetylcholine (Ach) of oleuropein-treated groups were significantly higher than those of vehicle-treated group. The findings indicate that antihypertensive effects of oleuropein might be partly mediated by improving the release of nitric oxide, and antioxidant and sympathoplegic activities.

Topics: Acetylcholine; Animals; Antihypertensive Agents; Arginine; Blood Glucose; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Disease Models, Animal; Endothelium, Vascular; Hypertension, Renal; Iridoid Glucosides; Iridoids; Male; Molecular Structure; Nitric Oxide; Rats; Rats, Sprague-Dawley; Superoxide Dismutase

The presence of amyloid aggregates of the 42 amino acid peptide of amyloid beta (Aβ42) in the brain is the characteristic feature of Alzheimer's disease (AD). Amyloid beta (Aβ deposition is also found in muscle fibers of individuals affected by inclusion body myositis (sIBM), a rare muscular degenerative disease affecting people over 50. Both conditions are presently lacking an effective therapeutic treatment. There is increasing evidence to suggest that natural polyphenols may prevent the formation of toxic amyloid aggregates; this applies also to oleuropein aglycone (OLE), the most abundant polyphenol in extra virgin olive oil, previously shown to hinder amylin and Aβ aggregation. Here we evaluated the ability of OLE to interfere with Aβ proteotoxicity in vivo by using the transgenic CL2006 and CL4176 strains of Caenorhabditis elegans, simplified models of AD and of sIBM, which express human Aβ in the cytoplasm of body wall muscle cells. OLE-fed CL2006 worms displayed reduced Aβ plaque deposition, less abundant toxic Aβ oligomers, remarkably decreased paralysis and increased lifespan with respect to untreated animals. A protective effect was also observed in CL4176 worms but only when OLE was administered before the induction of the Aβ transgene expression. These effects were specific, dose-related, and not mediated by the known polyphenolic anti-oxidant activity, suggesting that, in this model organism, OLE interferes with the Aβ aggregation skipping the appearance of toxic species, as already shown in vitro for Aβ42.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Animals, Genetically Modified; Caenorhabditis; Disease Models, Animal; Humans; Iridoid Glucosides; Iridoids; Peptide Fragments; Pyrans; Vasodilator Agents

Dietary olive oil supplementation and more recently, olive oil phenols have been recommended as important therapeutic interventions in preventive medicine. Ole has several pharmacological properties, including antioxidant, anti-inflammatory, antiatherogenic, anticancer, antimicrobial, and antiviral and for these reasons, is becoming an important subject of study in recent years. The aim of this study was to investigate the effects of Ole aglycone on the modulation of the secondary events in mice subjected to intestinal IRI. This was induced in mice by clamping the superior mesenteric artery and the celiac trunk for 30 min, followed by release of the clamp, allowing reperfusion for 1 h. After 60 min of reperfusion, animals were killed for histological examination of the ileum tissue and immunohistochemical localization of proinflammatory cytokines (TNF-α and IL-1β) and adhesion molecules (ICAM-1 and P-sel); moreover, by Western blot analysis, we investigated the activation of NF-κB and IκBα. In addition, we evaluated the apoptosis process, as shown by TUNEL staining and Bax/Bcl-2 expressions. The results obtained by the histological and molecular examinations showed in Ole aglycone-treated mice, a decrease of inflammation and apoptosis pathway versus SAO-shocked mice. In conclusion, we propose that the olive oil compounds, in particular, the Ole aglycone, could represent a possible treatment against secondary events of intestinal IRI.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Apoptosis; Blotting, Western; Cell Adhesion Molecules; Cytokines; Disease Models, Animal; Immunohistochemistry; In Situ Nick-End Labeling; Intestinal Diseases; Iridoid Glucosides; Iridoids; Male; Mice; Olive Oil; Plant Oils; Polyphenols; Pyrans; Reperfusion Injury

Oleuropein (OE) is a well-known antioxidant polyphenol from olive oil. The purpose of this study was to determine the potential neuroprotective effects of oleuropein in an experimental spinal cord injury model.. Rats were randomly divided into four groups of 21 rats each as follows: sham-operated group, trauma group, and OE treatment groups (20 mg/kg, i.p., immediately and 1 hour after spinal cord injury). Spinal cord samples were taken 24 hours after injury and studied for determination of malondialdehyde and glutathione levels, histopathological assessment, immunohistochemistry of Bax and Bcl-2, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling reaction. Behavioral testing was performed weekly up to 6 weeks post-injury.. The results showed that malondialdehyde levels were significantly decreased, and glutathione levels were significantly increased in OE treatment groups. Greater Bcl-2 and attenuated Bax expression could be detected in the OE-treated rats. OE significantly reduced terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-positive reaction and improved behavioral function than the trauma group.. These findings indicate that OE may be effective in protecting rat spinal cord from secondary injury.

Topics: Animals; Apoptosis; bcl-2-Associated X Protein; Disease Models, Animal; Female; Glutathione; Iridoid Glucosides; Iridoids; Lipid Peroxidation; Malondialdehyde; Neuroprotective Agents; Pyrans; Rats; Rats, Sprague-Dawley; Recovery of Function; Spinal Cord Injuries

Olives and olive products, an inevitable part of the Mediterranean diet, possess various beneficial effects, such as a decreased risk of cardiovascular disease and cancer. Oleuropein is a non-toxic secoiridoid found in the leaves and fruits of olive (Olea europaea L.). In this study, we have investigated the hepatoprotective activity of oleuropein in carbon tetrachloride (CCl(4))-induced liver injury in male BALB/cN mice. Oleuropein in doses of 100 and 200mg/kg was administered intraperitoneally (ip) once daily for 3 consecutive days, prior to CCl(4) administration (the preventive treatment), or once daily for 2 consecutive days 6h after CCl(4) intoxication (the curative treatment). CCl(4) intoxication resulted in a massive hepatic necrosis and increased plasma transaminases. Liver injury was associated with oxidative/nitrosative stress evidenced by increased nitrotyrosine formation as well as a significant decrease in superoxide dismutase activity and glutathione levels. CCl(4) administration triggered inflammatory response in mice livers by inducing expression of nuclear factor-kappaB, which coincided with the induction of tumor necrosis factor-alpha, cyclooxygenase-2 and inducible nitric oxide synthase. In both treatment protocols, oleuropein significantly attenuated oxidative/nitrosative stress and inflammatory response and improved histological and plasma markers of liver damage. Additionally, in the curative regimen, oleuropein prevented tumor necrosis factor-beta1-mediated activation of hepatic stellate cells, as well as the activation of caspase-3. The hepatoprotective activity of oleuropein was, at least in part, achieved through the NF-E2-related factor 2-mediated induction of heme oxygenase-1. The present study demonstrates antioxidant, anti-inflammatory, antiapoptotic, and antifibrotic activity of oleuropein, with more pronounced therapeutic than prophylactic effects.

Topics: Animals; Antioxidants; Carbon Tetrachloride; Chemical and Drug Induced Liver Injury; Disease Models, Animal; Glutathione; Heme Oxygenase-1; Iridoid Glucosides; Iridoids; Male; Mice; Mice, Inbred BALB C; Oleaceae; Oxidative Stress; Pyrans; Superoxide Dismutase

Oleuropein, a secoiridoid derived from olives and olive oil, has been known to possess antimicrobial, antioxidative, and anticancer activities. The purpose of the present study was to determine whether oleuropein has a protective effect against hepatic steatosis induced by a high fat diet (HFD) and to elucidate its underlying molecular mechanisms in mice.. Male C57BL/6N mice were fed a normal diet (ND), HFD, or an oleuropein-supplemented diet (OSD) for 10 weeks. The plasma and hepatic lipid levels were determined, and the hepatic gene and protein expression levels were analysed via RT-PCR and Western blotting, respectively.. The supplementation of HFD with oleuropein reversed the HFD-induced increases in liver weight along with plasma and hepatic lipid levels in mice. The expression of Wnt10b inhibitor genes, such as secreted firizzed-related sequence protein 5 and dickkopf homolog 2, was downregulated, whereas the β-catenin protein expression was upregulated in the liver of OSD-fed mice compared to HFD-fed mice. Fibroblast growth factor receptor 1 (FGFR1), phosphoextracellular-signal-regulated kinase 1/2, cyclin D, and E2F transcription factor 1, along with several key transcription factors and their target genes involved in adipogenesis, were downregulated by oleuropein. OSD-fed mice exhibited decreased expression of the toll-like-receptor-(TLR)-mediated signaling molecules (TLR2, TLR4, and myeloid differentiation primary-response gene 88) and proinflammatory cytokines, in their livers, as compared to HFD mice.. These results suggest that the protective effects of oleuropein against HFD-induced hepatic steatosis in mice appear to be associated with the Wnt10b- and FGFR1-mediated signaling cascades involved in hepatic lipogenesis, along with the TLR2- and TLR4-mediated signaling implicated in hepatic steatosis.

Topics: Animals; Antioxidants; beta Catenin; Body Weight; Dietary Fats; Disease Models, Animal; Extracellular Signal-Regulated MAP Kinases; Fatty Liver; Gene Expression; Iridoid Glucosides; Iridoids; Lipogenesis; Liver; Liver Cirrhosis; Male; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Organ Size; Pyrans; Signal Transduction; Toll-Like Receptors

Several olive oil phenolic compounds, such us oleuropein have attracted considerable attention because of their antioxidant activity, anti-atherosclerotic and anti-inflammatory properties. The aim of this study was to investigate the effects of oleuropein aglycone, a hydrolysis product of oleuropein, in a mouse model of carrageenan-induced pleurisy.. Mice were anaesthetized and subjected to a skin incision at the level of the left sixth intercostals space. The underlying muscle was dissected and saline or saline containing 2% λ-carrageenan was injected into the pleural cavity.. Injection of carrageenan elicited an acute inflammatory response characterized by: infiltration of neutrophils in lung tissues (P < 0.01 versus sham. P < 0.01 versus carrageenan) and subsequent lipid peroxidation (P < 0.01 versus sham. P < 0.01 versus carrageenan), increased production of tumor necrosis factor-α and interleukin-1β (P < 0.01 versus sham. P < 0.01 versus carrageenan), increased expression of adhesion molecules, increased synthesis of nitric oxide (P < 0.01 versus sham. P < 0.01 versus carrageenan), nitrotyrosine and poly-ADP-ribose (P < 0.01 versus sham. P < 0.01 versus carrageenan). Administration of oleuropein aglycone 30 min after the challenge with carrageenan, caused a significant reduction of all the parameters of inflammation measured.. Thus, we propose that olive oil phenolic constituents may be useful in the treatment of various inflammatory diseases.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Carrageenan; Disease Models, Animal; Hydrolysis; Intercellular Adhesion Molecule-1; Interleukin-1beta; Iridoid Glucosides; Iridoids; Lipid Peroxidation; Lung; Male; Mice; Nitric Oxide; Olive Oil; P-Selectin; Phenols; Plant Oils; Pleurisy; Poly Adenosine Diphosphate Ribose; Pyrans; Tumor Necrosis Factor-alpha; Tyrosine

The aim of this study was to investigate the effect of oleuropein aglycone, an olive oil compound, on the modulation of the inflammatory response in mice subjected to collagen-induced arthritis (CIA). CIA was induced in mice by an intradermal injection of 100 μl of an emulsion containing 100 μg of bovine type II collagen (CII) and complete Freund's adjuvant (CFA) at the base of the tail. On day 21, a second injection of CII in CFA was administered. Mice developed erosive hind paw arthritis when immunized with CII in CFA. Macroscopic clinical evidence of CIA first appeared as periarticular erythema and edema in the hind paws. The incidence of CIA was 100% by day 28 in the CII-challenged mice and the severity of CIA progressed over a 35-day period with resorption of bone. The histopathology of CIA included erosion of the cartilage at the joint. Treatment with oleuropein aglycone starting at the onset of arthritis (day 25) ameliorated the clinical signs at days 26 to 35 and improved histological status in the joint and paw. The degree of oxidative and nitrosative damage was also significantly reduced in oleuropein aglycone-treated mice. Plasma levels of the proinflammatory cytokines were also significantly reduced by oleuropein aglycone. In addition, we have confirmed the beneficial effects of oleuropein aglycone on an experimental model of CIA in a therapeutic regimen of post-treatment, with treatment started at day 28, demonstrating that oleuropein aglycone exerts an anti-inflammatory effect during chronic inflammation and ameliorates the tissue damage associated with CIA.

Topics: Alcohol Oxidoreductases; Animals; Anti-Inflammatory Agents, Non-Steroidal; Arthritis, Experimental; Cattle; Collagen Type II; Cytokines; Dinoprostone; Disease Models, Animal; Disease Progression; Drug Administration Schedule; Drug Evaluation, Preclinical; Iridoid Glucosides; Iridoids; Joints; Male; Mice; Mice, Inbred DBA; Nitric Oxide Synthase Type II; Olive Oil; Peroxidase; Plant Oils; Pyrans

Oxidative stress may play an important role in the pathogenesis of non-alcoholic steatohepatitis (NASH). Oleuropein, the active constituent of olive leaf, possesses anti-oxidant, hypoglycaemic, and hypolipidaemic activities. We aimed to investigate the preventive effects of olive leaf extract on hepatic fat accumulation in a rat model of NASH.. Spontaneously hypertensive/NIH-corpulent rats were fed a diet of AIN-93G with or without olive leaf extract (500, 1000, 2000 mg/kg diet, and control; 5 rats each) for 23 weeks. Serological and histopathological findings, anti-oxidative activity, and the alteration of fatty acid synthesis in the liver were evaluated.. Histopathologically, a diet of AIN-93G containing more than 1000 mg/kg olive leaf extract had a preventive effect for the occurrence of NASH. Thioredoxin-1 expression in the liver was more evident in rats fed this diet, and 4-hydroxynonenal expression in the liver was less evident in these rats. There were no significant differences in the activities of hepatic carnitine palmitoyltransferase, fatty acid synthase, malic enzyme, and phosphatidic acid phosphohydrolase among the groups.. Our data suggest that olive leaf extract may help prevent NASH, presumably through its anti-oxidative activity.

Topics: Aldehydes; Animal Feed; Animals; Antioxidants; Blood Chemical Analysis; Disease Models, Animal; Fatty Liver; Iridoid Glucosides; Iridoids; Liver; Male; Olea; Organ Size; Oxidative Stress; Plant Leaves; Pyrans; Rats; Rats, Inbred SHR; Thioredoxins

Oleuropein, an active constituent of olive leaf, has a variety of pharmacological activities associated with its capacity to scavenge reactive oxygen species. Oleuropein is also reported to have protective effects against non-alcoholic fatty liver disease (NAFLD) in vivo. In this study, gene expression profiling of hepatic tissues was examined, and transcription factors (TFs) with target genes that were modulated by oleuropein were identified to gain insights into the molecular mechanisms for the hepatoprotective action of this compound. C57BL/6N mice were fed either a high-fat diet (HFD) or 0.03% oleuropein-supplemented HFD for 10 weeks, after which their livers were subjected to oligo DNA microarray analysis. The oleuropein with which the HFD was supplemented reduced the hepatic mRNA level of the genes that encoded the key regulators of the hepatic fatty acid uptake and transport. In addition, the oleuropein reduced the expression of a number of hepatic genes involved in the oxidative stress responses and detoxification of lipid peroxidation products and proinflammatory cytokine genes. The (putative) candidate TFs that bound to the promoters of the genes regulated at least threefold (both up and down) by oleuropein were implicated in the lipogenesis, inflammation, insulin resistance, fibrosis, and cell proliferation and differentiation, which implies that the mechanisms that underlie the beneficial effects of oleuropein on NAFLD may be multifactorial.

Topics: Animals; Dietary Fats; Disease Models, Animal; Fatty Liver; Gene Expression Profiling; Gene Expression Regulation; Iridoid Glucosides; Iridoids; Lipid Metabolism; Liver; Male; Mice; Mice, Inbred C57BL; Non-alcoholic Fatty Liver Disease; Nutrigenomics; Oligonucleotide Array Sequence Analysis; Pyrans; Transcription Factors

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

Topics: Animals; Antiviral Agents; Cell Line; Disease Models, Animal; Dose-Response Relationship, Drug; Ducks; Flowers; Hepatitis B; Hepatitis B Surface Antigens; Hepatitis B virus; Hepatitis B Virus, Duck; Hepatitis, Viral, Animal; Humans; Iridoid Glucosides; Iridoids; Jasminum; Phytotherapy; Plant Extracts; Pyrans; Viremia; Virus Replication

Patients with diabetes mellitus are likely to develop certain complication such as retinopathy, nephropathy and neuropathy as a result of oxidative stress and overwhelming free radicals. Treatment of diabetic patients with antioxidant may be of advantage in attenuating these complications. Oleuropein, the active constituent of olive leaf (Olea europaea), has been endowed with many beneficial and health promoting properties mostly linked to its antioxidant activity. This study aimed to evaluate the significance of supplementation of oleuropein in reducing oxidative stress and hyperglycemia in alloxan-induced diabetic rabbits. After induction of diabetes, a significant rise in plasma and erythrocyte malondialdehyde (MDA) and blood glucose as well as alteration in enzymatic and non-enzymatic antioxidants was observed in all diabetic animals. During 16 weeks of treatment of diabetic rabbits with 20 mg/kg body weight of oleuropein the levels of MDA along with blood glucose and most of the enzymatic and non-enzymatic antioxidants were significantly restored to establish values that were not different from normal control rabbits. Untreated diabetic rabbits on the other hand demonstrated persistent alterations in the oxidative stress marker MDA, blood glucose and the antioxidant parameters. These results demonstrate that oleuropein may be of advantage in inhibiting hyperglycemia and oxidative stress induced by diabetes and suggest that administration of oleuropein may be helpful in the prevention of diabetic complications associated with oxidative stress.

Topics: Animals; Antioxidants; Blood Glucose; Body Weight; Diabetes Mellitus, Experimental; Disease Models, Animal; Hypoglycemic Agents; Iridoid Glucosides; Iridoids; Oleaceae; Phytotherapy; Plant Leaves; Pyrans; Rabbits