Oleuropein protects L-02 cells against H2O2-induced oxidative stress by increasing SOD1, GPx1 and CAT expression

From Epimedium to Neuroprotection: Exploring the Potential of Wushanicaritin

Epimedium has been used for functional foods with many beneficial functions to human health. Wushanicaritin is one of the most important chemicals int Epimedium. This study investigated the neuroprotective effects of wushanicaritin and potential underlying mechanisms. The results demonstrated that wushanicaritin possessed superior intercellular antioxidant activity compared to icaritin. Wushanicaritin, with an EC50 value of 3.87 μM, showed better neuroprotective effect than quercetin, a promising neuroprotection agent. Wushanicaritin significantly reversed lactate dehydrogenase release, reactive oxygen species generation, cell apoptosis, and mRNA expression related to cell apoptosis and oxidative defense, in glutamate-induced PC-12 cells. Wushanicaritin could also maintain the enzymatic antioxidant defense system and mitochondrial function. The suppression of caspase-3 activation and amelioration of mitochondrial membrane potential loss and nucleus morphology changes were involved in the antiapoptotic effect of wushanicaritin. These findings suggested that wushanicaritin possesses excellent intercellular antioxidant and neuroprotective activities, showing potential promise in functional foods.

miR-128-3p is involved in aluminum-induced cognitive impairment by regulating the Sirt1-Keap1/Nrf2 pathway

Aluminum (Al) is a common neurotoxicant in the environment, but the molecular mechanism of its toxic effects is still unclear. Studies have shown that aluminum exposure causes an increase in neuronal apoptosis. The aim of this study was to investigate the mechanism and signaling pathway of neuronal apoptosis induced by aluminum exposure. The rat model was established by intraperitoneal injection of maltol aluminum for 90 days. The results showed that the escape latency of the three groups exposed to maltol aluminum was higher than that of the control group on the 3rd, 4th and 5th days of the positioning cruise experiment (P < 0.05). On the 6th day of the space exploration experiment, compared with the control group(6.00 ± 0.71,15.33 ± 1.08) and the low-dose group(5.08 ± 1.69,13.67 ± 1.09), the number of times that the high-dose group crossed the platform(2.25 ± 0.76) and the platform quadrant(7.58 ± 1.43) was significantly reduced (P < 0.01). The relative expression levels of Sirt1 and Nrf2 in hippocampal tissues of all groups decreased gradually with increasing maltol aluminum exposure dose the relative expression levels of Sirt1 and Nrf2 in high-dose group (0.261 ± 0.094,0.325 ± 0.108) were significantly lower than those in control group (1.018 ± 0.222,1.009 ± 0.156)(P < 0.05). The relative expression level of Keap1 increased gradually with increasing maltol aluminum exposure dose (P < 0.05). The relative expression level of miR-128-3p in the high-dose group(1.520 ± 0.280) was significantly higher than that in the control group(1.000 ± 0.420) (P < 0.05). The content of GSH-Px in the hippocampus of rats decreased with increasing dose. ROS levels gradually increased. We speculated that subchronic aluminum exposure may lead to the activation of miR-128-3p in rat hippocampus of rats, thereby inhibiting the Sirt1-Keap1/Nrf2 pathway so that the Sirt1-Keap1/Nrf2 pathway could not be activated to exert antioxidant capacity, resulting in an imbalance in the antioxidant system of rats and the apoptosis of neurons, which caused reduced cognitive impairment in rats.

Structure characterization and anti-fatigue activity of an acidic polysaccharide from Panax ginseng C. A. Meyer

ETHNOPHARMACOLOGICAL RELEVANCE

Panax ginseng C. A. Meyer is a traditional Chinese herbal medicine, which has been used in China for more than 2000 years. Its traditional effect of "invigorating vitality" is mainly reflected in anti-fatigue. However, due to the difficulty of identification of polysaccharide structure, there are few reports on homogeneous ginseng polysaccharide, and the molecular mechanism of its anti-fatigue effect remains to be further explored.

AIM OF THE STUDY

In order to find the homogenous ginseng polysaccharide with the most anti-fatigue effect, this study is for the first time extracted, isolated and structurally identified polysaccharide monomer from Mountain Cultivated Ginseng (MCG). Then the anti-fatigue activity and molecular mechanism were studied.

MATERIALS AND METHODS

The structure of ginseng acidic polysaccharide APS-1 prepared by high performance gel permeation chromatography (HPGPC) was determined by acid hydrolysis/HPLC, methylation/GC-MS and NMR analysis. Anti-fatigue effect was evaluated by exhaustive swimming model, and AMPK axis-related proteins were detected by Western blot.

RESULTS

APS-1 significantly prolonged fatigue tolerance time, alleviated accumulation of BLA, LDH and BUN, increased activities of SOD and CAT, alleviated oxidative damage caused by MDA, increased activity of CK, regulated glycolysis, and alleviated muscle fiber contraction. The expressions of LKB1, p-AMPK, PGC-1α and Glut4 in muscle were significantly up-regulated.

CONCLUSIONS

The anti-fatigue effect of APS-1 was significantly, and the molecular mechanism may be related to the activation of AMPK axis signaling pathway to improve glucose uptake and mitochondrial function.

Oleuropein Attenuates Oxidative Stress in Human Trophoblast Cells

Olive-derived bioactive compound oleuropein was evaluated against damage induced by hydrogen peroxide in human trophoblast cells in vitro, by examining the changes in several markers implicated in oxidative stress interactions in the placenta. Trophoblast HTR-8/SVneo cells were preincubated with OLE at 10 and 100 µM and exposed to H₂O₂, as a model of oxidative stress. Protein and lipid peroxidation, as well as antioxidant enzymes' activity, were determined spectrophotometrically, and DNA damage was evaluated by comet assay. iNOS protein expression was assessed by Western blot, while the mRNA expression of pro- and anti-apoptotic genes BAX and BCL2 and transcription factor NFE2L2, as well as cytokines IL-6 and TNF α were determined by qPCR. Oleuropein demonstrated cytoprotective effects against H₂O₂ in trophoblast cells by significantly improving the antioxidant status and preventing protein and lipid damage, as well as reducing the iNOS levels. OLE reduced the mRNA expression of IL-6 and TNF α, however, it did not influence the expression of NFE2L2 or the BAX/BCL2 ratio after H₂O₂ exposure. Oleuropein per se did not lead to any adverse effects in HTR-8/SVneo cells under the described conditions, confirming its safety in vitro. In conclusion, it significantly attenuated oxidative damage and restored antioxidant functioning, confirming its protective role in trophoblast.

MaNmrA, a Negative Transcription Regulator in Nitrogen Catabolite Repression Pathway, Contributes to Nutrient Utilization, Stress Resistance, and Virulence in Entomopathogenic Fungus Metarhizium acridum

Simple Summary

Nutrient metabolism is closely related to the growth, development, and pathogenicity of pathogenic fungi. The nitrogen catabolite repression (NCR) pathway is a well-known fungal nitrogen source regulation path, in which NmrA plays an important regulatory role. Here, we reported a negative regulatory protein MaNmrA, the NmrA homologous protein, in the entomopathogenic fungus Metarhizium acridum, and found that it played important roles in carbon and nitrogen metabolism, growth, stress tolerance, and virulence of M. acridum. Our work will provide a theoretical basis for further exploring the functions of NCR pathway related genes in entomopathogenic fungi.

Abstract

The NCR pathway plays an important regulatory role in the nitrogen metabolism of filamentous fungi. NmrA, a central negative regulatory protein in the NCR pathway and a key factor in sensing to the carbon metabolism, plays important roles in pathogenic fungal nutrition metabolism. In this study, we characterized the functions of MaNmrA in the insect pathogenic fungus M. acridum. Multiple sequence alignments found that the conserved domain (NAD/NADP binding domain) of MaNmrA was highly conservative with its homologues proteins. Deletion of MaNmrA improved the utilization of multiple carbon sources (such as glucose, mannose, sucrose, and trehalose) and non-preferred nitrogen sources (such as NaNO₃ and urea), significantly delayed the conidial germination rate and reduced the conidial yield. The MaNmrA-disruption strain (ΔMaNmrA) significantly decreased tolerances to UV-B and heat-shock, and it also increased the sensitivity to the hypertonic substance sorbitol, oxygen stress substance H₂O₂, and cell wall destroyer calcofluor white, indicating that loss of MaNmrA affected cell wall integrity, tolerances to hypertonic and oxidative stress. Bioassays demonstrated that disruption of MaNmrA decreased the virulence in both topical inoculation and intrahemocoel injection tests. Further studies revealed that the appressorium formation, turgor pressure, and colonization in hemolymph were significantly reduced in the absence of MaNmrA. Our work will deepen the functional cognition of MaNmrA and make a contribution to the study of its homologous proteins.

Ocular Application of Oleuropein in Dry Eye Treatment: Formulation Studies and Biological Evaluation

Background. Oleuropein is already known for its numerous pharmacological properties, but its activity in the ocular field has not yet been investigated. The study aims to verify a possible use of oleuropein (OLE)-based eye drops both in terms of efficacy in dry eye syndrome and stability in aqueous solution. Methods. OLE was co-precipitated with HP-β-cyclodextrin, and the obtained complex was encapsulated into liposomes prepared by hydration of a lipid film composed of Lipoid S100 and cholesterol with different pH buffer solutions. The hydrated vesicles were shrunk by ultrasonication or extrusion. The preparations were characterized from the physicochemical point of view by subjecting them to differential scanning calorimetry, ATR-FTIR, dynamic light scattering analysis, and microscopy. Subsequently, OLE protective activity against hyperosmotic and oxidative stress on rabbit corneal epithelial cells (RCE) was evaluated. Results. The liposomal vesicles obtained after extrusion showed a tendency towards greater encapsulation efficiency (up to 80.77%) compared to that obtained by sonication, and the liposomes hydrated in pH 5.5 solution tended to incapsulate more than the neutral ones. Ultrasonication produced two-dimensional populations of liposomes, the largest of which reached 2149 nm. On the contrary, the extruded liposomes showed homogeneous diameters of about 250 nm. Complexation with cyclodextrin and subsequent encapsulation in liposomes greatly increased the OLE stability in aqueous solution, especially at 4 °C and for the extruded formulations. OLE aqueous solution (OLE7.4-sol, reference) and neutral extruded liposomes (F7.4-e) were well tolerated on RCE cells. Moreover, OLE was able to control the effects of hyperosmolarity on ocular surface cells and to prevent oxidative stress-induced loss of cell viability.

Dietary rational targeting of redox-regulated genes

Nutrigenomics is the study of how food and associated nutrients affect gene expression. This field sits at the intersection of diet, the genome and health with the ultimate goal of exploiting its understanding to design a precision nutrition strategy for humans. We have studied diet and nutrigenomics in the context of something we call "dietary rational gene targeting." Here, healthy diet is used to alter disease-causing gene expression back toward the normal to treat various diseases and conditions while lowering treatment cost and toxicity. In this paper, we discuss the use of this strategy to modulate the expression of redox-associated genes to improve human health. Most human disorders are associated, at least to some extent, with oxidative stress and so treatments (including diet) that target redox-related genes have major potential clinical significance. Healthy dietary options here are wide-ranging and include whole foods and botanical-based beverages. In some cases, botanical supplements may also be useful gene modulators although their health benefits are less clear. Key redox gene targets for these dietary agents include antioxidant genes, related transcription factors, detoxification genes, and DNA repair genes. Other important considerations include bioavailability, the contribution of the microbiome, and advancing technologies. In this review, specific examples of redox associated genes and pathologies and their potential treatment with healthy diet are presented to illustrate our approach. This will also serve as a foundation for the design of future clinical studies to improve diet-related health.

Olive Oil: Nutritional Applications, Beneficial Health Aspects and its Prospective Application in Poultry Production

Plant polyphenols have promoting health features, including anti-mutagenic, anti-inflammatory, anti-thrombotic, anti-atherogenic, and anti-allergic effects. These polyphenols improve the immune system by affecting the white blood cell proliferation, as well as by the synthesis of cytokines and other factors, which contribute to immunological resistance. Olive trees are one of the most famous trees in the world. Whereas, olive olive oil and derivatives represent a large group of feeding resource for farm animals. In recent years, remarkable studies have been carried out to show the possible use of olive oil and derivatives for improvement of both animal performance and product quality. In vivo application of olive oil and its derived products has shown to maintain oxidative balance owing to its polyphenolic content. Consumption of extra virgin olive oil reduces the inflammation, limits the risk of liver damage, and prevents the progression of steatohepatitis through its potent antioxidant activities. Also, the monounsaturated fatty acids content of olive oil (particularly oleic acid), might have positive impacts on lipid peroxidation and hepatic protection. Therefore, this review article aims to highlight the nutritional applications and beneficial health aspects of olive oil and its effect on poultry production.

Effect of oleuropein on oxidative stress, inflammation and apoptosis induced by ischemia-reperfusion injury in rat kidney

AIMS

This study aimed to evaluate the effect of oleuropein (OLE), the main phenolic compound present in olive leaves, on kidney ischemia-reperfusion injury (IRI) and to explore the underlying protective mechanism.

MAIN METHODS

Rat kidneys were subjected to 60 min of bilateral warm ischemia followed by 120 min of reperfusion. OLE was administered orally 48 h, 24 h and 30 min prior to ischemia at doses of 10, 50 and 100 mg/kg body weight. The creatinine, urea, uric acid concentrations and lactate dehydrogenase (LDH) activity in plasma were evaluated. Oxidative stress and inflammation parameters were also assessed. Renal expression of AMP-activated protein kinase (p-AMPK), endothelial nitric oxide synthase (eNOS), mitogen-activated protein kinases (MAPK), inflammatory proteins and apoptotic proteins were evaluated using Western blot.

KEY FINDINGS

Our results showed that OLE at 50 mg/kg reduced kidney IRI as revealed by a significant decrease of plasmatic creatinine, urea, uric acid concentrations and LDH activity. In parallel, OLE up-regulated antioxidant capacities. Moreover, OLE diminished the level of CRP and the expression of cyclooxygenase 2 (COX-2). Finally, OLE enhanced AMPK phosphorylation as well as eNOS expression whereas MAPK, and cleaved caspase-3 implicated in cellular apoptosis were attenuated in the ischemic kidneys.

SIGNIFICANCE

In conclusion, this study shows that OLE could be used as therapeutic agent to reduce IRI through its anti-oxidative, anti-inflammatory and anti-apoptotic properties.

The antioxidant activity and neuroprotective mechanism of isoliquiritigenin

Glycyrrhizae radix has been widely accepted as a functional food in Asia. Isoliquiritigenin is a characteristic bioactive chemical in this medicinal plant. In this work, the neuroprotective effect of isoliquiritigenin and the possible mechanisms were investigated. The results revealed that isoliquiritigenin exhibited better neuroprotective and antioxidant activities than quercetin, a commercial natural antioxidant. Isoliquiritigenin significantly inhibited the release of lactate dehydrogenase, and the generation of reactive oxygen species in H₂O₂-treated cells. The activities of superoxide dismutase, glutathione peroxidase and catalase were improved. The mRNA expression levels related to oxidative defense and cell apoptosis were reversed by isoliquiritigenin. Moreover, isoliquiritigenin might inhibit the cell apoptosis via ameliorating the loss of mitochondrial membrane potential and the change of nucleus morphology.

Selective chemiluminescent TURN-ON quantitative bioassay and imaging of intracellular hydrogen peroxide in human living cells

Hydrogen peroxide is an unavoidable by-product of cell metabolism, but when it is not properly managed by the body it can lead to several pathologies (e.g., premature aging, cardiovascular and neurodegenerative diseases, cancer). Several methods have been proposed for the measurement of intracellular H₂O₂ but none of them has proven to be selective. We developed a rapid all-in-one chemiluminescent bioassay for the quantification of H₂O₂ in living cells with a low limit of detection (0.15 μM). The method relies on an adamantylidene-1,2-dioxetane lipophilic probe containing an arylboronate moiety; upon reaction with H₂O₂ the arylboronate moiety is converted to the correspondent phenol and the molecule decomposes leading to an excited-state fragment that emits light. The probe has been successfully employed for quantifying intracellular H₂O₂ in living human endothelial, colon and keratinocyte cells exposed to different pro-oxidant stimuli (i.e., menadione, phorbol myristate acetate and lipopolysaccharide). Imaging experiments clearly localize the chemiluminescence emission inside the cells. Treatment of cells with antioxidant molecules leads to a dose-dependent decrease of intracellular H₂O₂ levels. As a proof of concept, the bioassay has been used to measure the antioxidant activity of extracts from Brassica juncea wastes, which contain glucosinolates, isothiocyanates and other antioxidant molecules.

Oxidative stress, nutritional antioxidants and beyond

Free radical-induced oxidative stress contributes to the development of metabolic syndromes (Mets), including overweight, hyperglycemia, insulin resistance and pro-inflammatory state. Most free radicals are generated from the mitochondrial electron transport chain; under physiological conditions, their levels are maintained by efficient antioxidant systems. A variety of transcription factors have been identified and characterized that control gene expression in response to oxidative stress status. Natural antioxidant compounds have been largely studied for their strong antioxidant capacities. This review discusses the recent progress in oxidative stress and mitochondrial dysfunction in Mets and highlights the anti-Mets, anti-oxidative, and anti-inflammatory effect of polyphenols as potential nutritional therapy.

Oleuropein-Induced Apoptosis Is Mediated by Mitochondrial Glyoxalase 2 in NSCLC A549 Cells: A Mechanistic Inside and a Possible Novel Nonenzymatic Role for an Ancient Enzyme

Oleuropein (OP) is a bioactive compound derived from plants of the genus Oleaceae exhibiting antitumor properties in several human cancers, including non-small-cell lung cancer (NSCLC). Recent evidence suggests that OP has proapoptotic effects on NSCLC cells via the mitochondrial apoptotic pathway. However, the exact molecular mechanisms behind the apoptogenic action of OP in NSCLC are still largely unknown. Glyoxalase 2 (Glo2) is an ancient enzyme belonging to the glyoxalase system involved in the detoxification of glycolysis-derived methylglyoxal. However, emerging evidence suggests that Glo2 may have also nonenzymatic roles in some malignant cells. In the present study, we evaluated whether and how Glo2 participated in the proapoptotic effects of OP in NSCLC A549 cells. Our results indicate that OP is able to induce apoptosis in A549 cells through the upregulation of mitochondrial Glo2 (mGlo2), mediated by the superoxide anion and Akt signaling pathway. Moreover, our data shows that the proapoptotic role of mGlo2, observed following OP exposure, occurs via the interaction of mGlo2 with the proapoptotic Bax protein. Conversely, OP does not alter the behavior of nonmalignant human BEAS-2B cells or mGlo2 expression, thus suggesting a specific anticancer role for this bioactive compound in NSCLC. Our data identify a novel pathway through which OP exerts a proapoptotic effect in NSCLC and suggest, for the first time, a novel, nonenzymatic antiapoptotic role for this ancient enzyme in NSCLC.

Hydroxytyrosol, Tyrosol and Derivatives and Their Potential Effects on Human Health

The Mediterranean diet and olive oil as its quintessential part are almost synonymous with a healthy way of eating and living nowadays. This kind of diet has been highly appreciated and is widely recognized for being associated with many favorable effects, such as reduced incidence of different chronic diseases and prolonged longevity. Although olive oil polyphenols present a minor fraction in the composition of olive oil, they seem to be of great importance when it comes to the health benefits, and interest in their biological and potential therapeutic effects is huge. There is a growing body of in vitro and in vivo studies, as well as intervention-based clinical trials, revealing new aspects of already known and many new, previously unknown activities and health effects of these compounds. This review summarizes recent findings regarding biological activities, metabolism and bioavailability of the major olive oil phenolic compounds—hydroxytyrosol, tyrosol, oleuropein, oleocanthal and oleacein—the most important being their antiatherogenic, cardioprotective, anticancer, neuroprotective and endocrine effects. The evidence presented in the review concludes that these phenolic compounds have great pharmacological potential, however, further studies are still required.

Cytoprotective effects of Avenathramide C against oxidative and inflammatory stress in normal human dermal fibroblasts

Natural polyphenols are promising anti-aging compounds not only for their antioxidant activity, but also their ability to activate specific cellular pathways mediating the aging process. Avenanthramide C (Avn C), found exclusively in oats, is a natural antioxidant associated with free radical scavenging; however, it is how this compound elicits other protective effects. We investigated the intracellular antioxidant activity of Avn C and other cytoprotective potential in normal human skin fibroblasts exposed to extracellular stress. Avn C reduced H2O2-induced oxidative stress by reducing intracellular free radical levels and antioxidant gene transcripts. Avn C also resulted in decreased levels of gene transcripts encoding pro-inflammatory cytokines in response to H2O2 or tumor necrosis factor-α (TNF-α). This reduction in cytokine gene transcription occurred concomitantly with reduced phosphorylated nuclear factor-κB (NF-κB) p65, and decreased NF-κB DNA binding. Avn C further induced heme oxygense-1 (HO-1) expression through increased Nrf2 DNA binding activity, demonstrating a second mechanism by which Avn C attenuates cellular stress. Collectively, our findings indicate that Avn C protects normal human skin fibroblasts against oxidative stress and inflammatory response through NF-κB inhibition and Nrf2/HO-1 activation.

Oxymatrine and its metabolite matrine contribute to the hepatotoxicity induced by radix Sophorae tonkinensis in mice

Previous studies by our group demonstrated that radix Sophorae tonkinensis could induce hepatotoxicity. However, it remains unclear which components of this herb may be responsible for its hepatotoxicity. The present study aimed to investigate the hepatic toxicity of treatment with matrine (MT) and oxymatrine (OMT) alone or simultaneously. Furthermore, the current study aimed to identify whether the hepatotoxicity induced by OMT is actually the toxic characterization of its metabolite MT. Hepatotoxicity was evaluated by biochemical and histopathological approaches in subchronic toxicity in mice, as well as via evaluation of cytotoxicity and enzyme leakage in AML12 liver cells. The results indicated that treatment of mice with OMT and MT individually or simultaneously resulted in centrilobular hypertrophy in the liver at doses equivalent to that contained in radix S. tonkinensis at a hepatotoxic dose, suggesting that MT and OMT are likely hepatotoxic components of this herb. OMT-induced hepatotoxicity may be primarily exerted via its metabolite MT in mice. Furthermore, OMT combined with MT was observed to be more toxic compared with OMT or MT alone. These results extend our understanding of the hepatotoxicity of radix S. tonkinensis and its active ingredients.

The hepatoprotective effects of Sedum sarmentosum extract and its isolated major constituent through Nrf2 activation and NF-κB inhibition

BACKGROUND

Sedum sarmentosum, which is recorded in Chinese Pharmacopoeia, has been applied clinically to treat liver and gallbladder diseases.

PURPOSE

This study aimed to explore the hepatoprotective effect of S. sarmentosum less polar extract (SSE) against ANIT-induced liver injury in rats, and the protective activity and mechanism of one major constituent isolated from this extract on D-GalN-induced human hepatic QSG7701 cell damage.

METHODS

Rats were divided into groups and then administrated intragastrically with SSE at doses of 100, 200 and 400 mg/kg for 7 days. They were modeled in the experiments with ANIT (70 mg/kg) to induce liver injury after the sixth day administration. The levels of serum biochemical markers ALT, AST, ALP, GGT/γ-GT, DBiL, TBiL, ALB, TP, and bile flow rate, as well as the histopathology of the liver tissue were used as indices of liver damage and measured. The inflammatory response and oxidative stress were thought to be key contributors to ANIT-induced liver injury in rats. Therefore, the inflammatory mediators (TNF-α, IFN-γ, IL-4) and oxidative stress (ROS, SOD, GSH-PX) were measured in the serum and liver homogenates, respectively. Next, phytochemical research was performed to produce the main component, and the isolated compound was evaluated for its hepatoprotective activity against QSG7701 cell injured by D-GalN through the measurement of cell viabilities, ALT, AST, IL-1β, TNF-α, IL-6, ROS, GSH-PX and SOD productions. Furthermore, the protein expression of the Nrf2 and NF-κB pathways were analyzed by western blotting.

RESULTS

SSE had an obvious effect on the decreases of ALT, AST, ALP, GGT/γ-GT, DBiL and TBiL levels, the increases of ALB and TP levels in serum, and the ANIT-induced deceleration in bile flow for liver injury. Meanwhile, SSE pretreatment alleviated ANIT-induced liver pathological injuries exhibited by HE stain of the liver. Moreover, SSE significantly suppressed levels of pro-inflammatory cytokines TNF-α and IFN-γ, and elevated level of anti-inflammatory cytokine IL-4 in serum. SSE also attenuated oxidative stress by reducing ROS level and by enhancing antioxidative enzymes (SOD and GSH-PX) activities after ANIT administration in liver tissue. Further, the major compound shown in HPLC was isolated from SSE. Its structure was identified by the spectroscopic data analysis and comparison with literature values. The principal constituent had potent protective effect on D-GalN-induced QSG7701 cells damage in a dose dependent manner with survival rates of 58.2% and 69.5% at 10 μM and 20 μM, respectively. Its cytoprotective effect was associated with the reduction of ALT, AST, IL-1β, TNF-α, IL-6 and ROS levels, and the elevation of GSH-PX and SOD productions in QSG7701 cells induced by D-GalN. Western blotting showed that this compound enhanced the expression of Nrf2, HO1, NQO1 and GCLC, and inhibited D-GalN-induced IκBα and NF-κB p65 phosphorylation.

CONCLUSIONS

Current study showed that SSE treatment exerted a protective effect on ANIT-induced liver injury. The main compound δ-amyrone isolated from the extract was characterized as the effective component with hepatoprotective activity by promoting Nrf2 antioxidant defense and suppressing NF-κB inflammatory response.

Modulation of intestinal epithelium homeostasis by extra virgin olive oil phenolic compounds

Extra virgin olive oil polyphenols concentrate at the intestinal level and, by modulating the microbiota, oxidative status and inflammation, contribute to prevent the onset or delay the progression of inflammatory/degenerative diseases.

Oleuropein protects intracerebral hemorrhage-induced disruption of blood-brain barrier through alleviation of oxidative stress

BACKGROUND

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.

METHODS

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.

RESULTS

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.

CONCLUSION

Our study suggests oleuropein could be used as a promising therapeutic agent for ICH.