Hydroxytyrosol Exerts Anti-Inflammatory and Anti-Oxidant Activities in a Mouse Model of Systemic Inflammation

Dietary anti-inflammatory and anti-bacterial medicinal plants and its compounds in bovine mastitis associated impact on human life

Bovine mastitis (BM) is the most common bacterial mediated inflammatory disease in the dairy cattle that causes huge economic loss to the dairy industry due to decreased milk quality and quantity. Milk is the essential food in the human diet, and rich in crucial nutrients that helps in lowering the risk of diseases like hypertension, cardiovascular diseases and type 2 diabetes. The main causative agents of the disease include various gram negative, and positive bacteria, along with other risk factors such as udder shape, age, genetic, and environmental factors also contributes much for the disease. Currently, antibiotics, immunotherapy, probiotics, dry cow, and lactation therapy are commonly recommended for BM. However, these treatments can only decrease the rise of new cases but can't eliminate the causative agents, and they also exhibit several limitations. Hence, there is an urgent need of a potential source that can generate a typical and ideal treatment to overcome the limitations and eliminate the pathogens. Among the various sources, medicinal plants and its derived products always play a significant role in drug discovery against several diseases. In addition, they are also known for its low toxicity and minimum resistance features. Therefore, plants and its compounds that possess anti-inflammatory and anti-bacterial properties can serve better in bovine mastitis. In addition, the plants that are serving as a food source and possessing pharmacological properties can act even better in bovine mastitis. Hence, in this evidence-based study, we particularly review the dietary medicinal plants and derived products that are proven for anti-inflammatory and anti-bacterial effects. Moreover, the role of each dietary plant and its compounds along with possible role in the management of bovine mastitis are delineated. In this way, this article serves as a standalone source for the researchers working in this area to help in the management of BM.

Effect of olive leaf phytochemicals on the anti-acetylcholinesterase, anti-cyclooxygenase-2 and ferric reducing antioxidant capacity

In this study, the phytochemical profile of fifty olive leaves (OL) extracts from Spain, Italy, Greece, Portugal, and Morocco was characterized and their anti-cholinergic, anti-inflammatory, and antioxidant activities were evaluated. Luteolin-7-O-glucoside, isoharmnentin, and apigenin were involved in the acetylcholinesterase (AChE) inhibitory activity, while oleuropein and hydroxytyrosol showed noteworthy potential. Secoiridoids contributed to the cyclooxygenase-2 inhibitory activity and antioxidant capacity. Compounds such as oleuropein, ligstroside and luteolin-7-O-glucoside, may exert an important role in the ferric reducing antioxidant capacity. It should be also highlighted the role of hydroxytyrosol, hydroxycoumarins, and verbascoside concerning the antioxidant activity. This research provides valuable insights and confirms that specific compounds within OL extracts contribute to distinct anti-cholinergic, anti-inflammatory, and anti-oxidative effects.

Polyphenol-Rich Extracts from Agroindustrial Waste and Byproducts: Results and Perspectives According to the Green Chemistry and Circular Economy

Polyphenols are natural secondary metabolites found in plants endowed with multiple biological activities (antioxidant, anti-inflammatory, antimicrobial, cardioprotective, and anticancer). In view of these properties, they find many applications and are used as active ingredients in nutraceutical, food, pharmaceutical, and cosmetic formulations. In accordance with green chemistry and circular economy strategies, they can also be recovered from agroindustrial waste and reused in various sectors, promoting sustainable processes. This review described structural characteristics, methods for extraction, biological properties, and applications of polyphenolic extracts obtained from two selected plant materials of the Mediterranean area as olive (Olea europaea L.) and pomegranate (Punica granatum L.) based on recent literature, highlighting future research perspectives.

Anti-neuroinflammatory effect of hydroxytyrosol: a potential strategy for anti-depressant development

Introduction: Depression is a complex psychiatric disorder with substantial societal impact. While current antidepressants offer moderate efficacy, their adverse effects and limited understanding of depression's pathophysiology hinder the development of more effective treatments. Amidst this complexity, the role of neuroinflammation, a recognized but poorly understood associate of depression, has gained increasing attention. This study investigates hydroxytyrosol (HT), an olive-derived phenolic antioxidant, for its antidepressant and anti-neuroinflammatory properties based on mitochondrial protection. Methods: In vitro studies on neuronal injury models, the protective effect of HT on mitochondrial ultrastructure from inflammatory damage was investigated in combination with high-resolution imaging of mitochondrial substructures. In animal models, depressive-like behaviors of chronic restraint stress (CRS) mice and chronic unpredictable mild stress (CUMS) rats were examined to investigate the alleviating effects of HT. Targeted metabolomics and RNA-Seq in CUMS rats were used to analyze the potential antidepressant pathways of HT. Results: HT protected mitochondrial ultrastructure from inflammatory damage, thus exerting neuroprotective effects in neuronal injury models. Moreover, HT reduced depressive-like behaviors in mice and rats exposed to CRS and CUMS, respectively. HT's influence in the CRS model included alleviating hippocampal neuronal damage and modulating cytokine production, mitochondrial dysfunction, and brain-derived neurotrophic factor (BDNF) signaling. Targeted metabolomics in CUMS rats revealed HT's effect on neurotransmitter levels and tryptophan-kynurenine metabolism. RNA-Seq data underscored HT's antidepressant mechanism through the BDNF/TrkB signaling pathways, key in nerve fiber functions, myelin formation, microglial differentiation, and neural regeneration. Discussion: The findings underscore HT's potential as an anti-neuroinflammatory treatment for depression, shedding light on its antidepressant effects and its relevance in nutritional psychiatry. Further investigations are warranted to comprehensively delineate its mechanisms and optimize its clinical application in depression treatment.

Hydroxytyrosol Alleviates Methotrexate-Induced Pulmonary Fibrosis in Rats: Involvement of TGF-β1, Tissue Factor, and VEGF

Methotrexate (MTX) is an indispensable drug used for the treatment of many autoimmune and cancerous diseases. However, its clinical use is associated with serious side effects, such as lung fibrosis. The main objective of this study is to test the hypothesis that hydroxytyrosol (HT) can mitigate MTX-induced lung fibrosis in rats while synergizing MTX anticancer effects. Pulmonary fibrosis was induced in the rats using MTX (14 mg/kg/week, per os (p.o.)). The rats were treated with or without HT (10, 20, and 40 mg/kg/d p.o.) or dexamethasone (DEX; 0.5 mg/kg/d, intraperitoneally (i.p.)) for two weeks concomitantly with MTX. Transforming growth factor beta 1 (TGF-β1), interleukin-4 (IL-4), thromboxane A2 (TXA2), vascular endothelial growth factor (VEGF), 8-hydroxy-2-deoxy-guanosine (8-OHdG), tissue factor (TF) and fibrin were assessed using enzyme-linked immunosorbent assay (ELISA), immunofluorescence, and RT-PCR. Pulmonary fibrosis was manifested by an excessive extracellular matrix (ECM) deposition and a marked increase in TGF-β1 and IL-4 in lung tissues. Furthermore, cotreatment with HT or dexamethasone (DEX) significantly attenuated MTX-induced ECM deposition, TGF-β1, and IL-4 expression. Similarly, HT or DEX notably reduced hydroxyproline contents, TXA2, fibrin, and TF expression in lung tissues. Moreover, using HT or DEX downregulated the gene expression of TF. A significant decrease in lung contents of VEGF, IL-8, and 8-OHdG was also observed in HT + MTX- or DEX + MTX -treated animals in a dose-dependent manner. Collectively, the results of our study suggest that HT might represent a potential protective agent against MTX-induced pulmonary fibrosis.

Modulation of mi-RNA25/Ox-LDL/NOX4 signaling pathway by polyphenolic compound Hydroxytyrosol as a new avenue to alleviate cisplatin-induced acute kidney injury, a mechanistic study in rats

Acute kidney injury (AKI) caused by Cis is considered one of the most severe adverse effects, which restricts its use and efficacy. This study seeks to examine the potential reno-protective impact of phenolic compound Hydroxytyrosol (HT) against Cis-induced AKI and the possible involvement of the mi-RNA25/Ox-LDL/NOX4 pathway elucidating the probable implicated molecular mechanisms. Forty rats were placed into 5 groups. Group I received saline only. Group II received Cis only. Group III, IV, and V received 20, 50, and 100 mg/kg b.w, of HT, respectively, with Cis delivery. NOX4, Ox-LDL, and gene expression of mi-RNA 25, TNF-α, and HO-1 in renal tissue were detected. HT showed reno-protective effect and significantly upregulated mi-RNA 25 and HO-1 as well as decreased the expression of NOX4, Ox-LDL, and TNF-α. In conclusion, HT may be promising in the fight against Cis-induced AKI through modulation of mi-RNA25/Ox-LDL/NOX4 pathway.

Valorization of Olive Mill Byproducts: Recovery of Biophenol Compounds and Application in Animal Feed

This study aimed to recover the phenols from olive oil mill wastewater, a major pollutant of the oil industry, by using spray-drying technology to produce a new feed with a nutraceutical value for animal feed supplementation and to evaluate its effect on the productivity and nutritional quality of ewe milk. Forty-five Sarda ewes in late lactation (150 ± 2 d) and with homogeneous live weight (52 ± 1.5 kg) were randomly allotted into three groups and fed with three dietary treatments containing increasing levels of polyphenols: 0% (C), 0.1% (T0.1), and 0.2% (T0.2) of dry matter. No effect of the dietary treatments was found on the milk yield and composition. Interestingly, milk urea content (p < 0.0001) and somatic cell counts (p < 0.001) decreased as the level of polyphenols inclusion in the diet increased. The inclusion of phenols (0.2% of dry matter) in the diet of sheep was effective in increasing the vaccenic (C18:1 trans-11) and rumenic acid (C18: cis-9 trans-11) levels, which are beneficial for human health. Finally, the recovery of polyphenols via spray-drying technology and their incorporation into a new fortified feed can be a valid strategy for naturally improving the nutritional value of milk while valorizing an oil industry byproduct, reducing environmental impact, and promoting waste reuse that is in line with circular economy principles.

EVOO Polyphenols Exert Anti-Inflammatory Effects on the Microglia Cell through TREM2 Signaling Pathway

In Alzheimer's disease (AD), microglia, brain resident immune cells, become chronically inflammatory and neurotoxic. In recent years, neuroinflammation has attracted particular interest in the scientific community. The genetic variants of molecules associated with ''microgliopathies'', including the triggering receptor expressed in myeloid cells-2 (TREM2), result in increased risk of developing AD and cognitive decline. We performed a set of in vitro assays using human neuronal (SH-SY5Y) and microglial (BV2 and C13NJ) cell models. Cells were differentially treated with extra virgin olive oil (EVOO) polyphenols, oleuropein aglycone (OleA) and hydroxytyrosol (HT) before adding LPS. We evaluated the protective effects of these EVOO products by a set of biochemical and cell biology assays, including ELISA, MTT, ROS detection, Western blotting and immunofluorescence. Our results provide an integrated understanding of the neuroprotection exerted by polyphenols in terms of: (i) reduction of pro-inflammatory cytokines release (IL-6, IL-8, IP-10 and RANTES); (ii) activation of the TREM2-dependent anti-inflammatory pathway; (iii) enhancement of protective microglial activity favoring the M2 polarization phenotype. Such findings provide new and important insights into the mechanisms by which the dietary olive polyphenols exert beneficial properties against neuroinflammation and neuronal impairment.

Hydroxytyrosol Interference with Inflammaging via Modulation of Inflammation and Autophagy

Inflammaging refers to a chronic, systemic, low-grade inflammation, driven by immune (mainly macrophages) and non-immune cells stimulated by endogenous/self, misplaced or altered molecules, belonging to physiological aging. This age-related inflammatory status is characterized by increased inflammation and decreased macroautophagy/autophagy (a degradation process that removes unnecessary or dysfunctional cell components). Inflammaging predisposes to age-related diseases, including obesity, type-2 diabetes, cancer, cardiovascular and neurodegenerative disorders, as well as vulnerability to infectious diseases and vaccine failure, representing thus a major target for anti-aging strategies. Phenolic compounds-found in extra-virgin olive oil (EVOO)-are well known for their beneficial effect on longevity. Among them, hydroxytyrosol (HTyr) appears to greatly contribute to healthy aging by its documented potent antioxidant activity. In addition, HTyr can modulate inflammation and autophagy, thus possibly counteracting and reducing inflammaging. In this review, we reference the literature on pure HTyr as a modulatory agent of inflammation and autophagy, in order to highlight its possible interference with inflammaging. This HTyr-mediated activity might contribute to healthy aging and delay the development or progression of diseases related to aging.

Effects of Hydroxytyrosol in Endothelial Functioning: A Comprehensive Review

Pharmacologists have been emphasizing and applying plant and herbal-based treatments in vascular diseases for decades now. Olives, for example, are a traditional symbol of the Mediterranean diet. Hydroxytyrosol is an olive-derived compound known for its antioxidant and cardioprotective effects. Acknowledging the merit of antioxidants in maintaining endothelial function warrants the application of hydroxytyrosol in endothelial dysfunction salvage and recovery. Endothelial dysfunction (ED) is an impairment of endothelial cells that adversely affects vascular homeostasis. Disturbance in endothelial functioning is a known precursor for atherosclerosis and, subsequently, coronary and peripheral artery disease. However, the effects of hydroxytyrosol on endothelial functioning were not extensively studied, limiting its value either as a nutraceutical supplement or in clinical trials. The action of hydroxytyrosol in endothelial functioning at a cellular and molecular level is gathered and summarized in this review. The favorable effects of hydroxytyrosol in the improvement of endothelial functioning from in vitro and in vivo studies were scrutinized. We conclude that hydroxytyrosol is capable to counteract oxidative stress, inflammation, vascular aging, and arterial stiffness; thus, it is beneficial to preserve endothelial function both in vitro and in vivo. Although not specifically for endothelial dysfunction, hydroxytyrosol safety and efficacy had been demonstrated via in vivo and clinical trials for cardiovascular-related studies.

Hydroxytyrosol and Its Potential Uses on Intestinal and Gastrointestinal Disease

In recent years, the phytoconstituents of foods in the Mediterranean diet (MD) have been the subject of several studies for their beneficial effects on human health. The traditional MD is described as a diet heavy in vegetable oils, fruits, nuts, and fish. The most studied element of MD is undoubtedly olive oil due precisely to its beneficial properties that make it an object of interest. Several studies have attributed these protective effects to hydroxytyrosol (HT), the main polyphenol contained in olive oil and leaves. HT has been shown to be able to modulate the oxidative and inflammatory process in numerous chronic disorders, including intestinal and gastrointestinal pathologies. To date, there is no paper that summarizes the role of HT in these disorders. This review provides an overview of the anti-inflammatory and antioxidant proprieties of HT against intestinal and gastrointestinal diseases.

Hydroxytyrosol: Its role in the prevention of cardiovascular diseases

In recent years, non-pharmacology treatments and their effectiveness have gained popularity due to their beneficial properties in the prevention of cardiovascular diseases. Phenolic compounds intake provides a natural means of improving in vivo antioxidant status. Thus, the purpose of this review is to discuss the potential benefits of hydroxytyrosol (HT), a phenolic compound with powerful antioxidant and anti-inflammatory properties, in preventing and reducing cardiovascular risk factors, concretely atherosclerosis. Closer inspection of the studies showed a significant improvement of lipid profile, antioxidant capacity and inflammatory state. A note of caution is due in vitro studies because the lack of validated approaches difficult the goodness of fit with the in vivo and clinical research. However, animal and clinical studies were very encouraging, determining HT supplementation useful on inflammation, oxidative stress, endothelial function and cardiovascular diseases in general.

Hydroxytyrosol decreases EDNRA expression through epigenetic modification in colorectal cancer cells

The Mediterranean diet (MD) is one of the healthiest ones and is associated with a lower incidence of cardiovascular and cerebrovascular diseases as well as cancer. Extra virgin olive oil (EVOO) is probably the most idiosyncratic component of this diet. EVOO has been attributed with many healthful effects, which may be due to its phenolic components, e.g. including hydroxytyrosol (HT). Recent studies suggest that EVOO and HT have molecular targets in human tissues and modulate epigenetic mechanisms. DNA methylation is one of the most studied epigenetic mechanisms and consists of the addition of a methyl group to the cytosines of the DNA chain. Given the purported health effects of EVOO (poly)phenols, we analyzed the changes induced by HT in DNA methylation, in a colorectal cancer cell line. Caco-2 cells were treated with HT for one week or with the demethylating agent 5'-azacytidine for 48 h. Global DNA methylation was assessed by ELISA. DNA bisulfitation was performed and Infinium Methylation EPIC BeadChips were used to analyze the specific methylation of CpG sites. We show an increase in global DNA methylation in Caco-2 cells after HT treatment, with a total of 32,141 differentially methylated (CpGs DMCpGs). Interestingly, our analyses revealed the endothelin receptor type A gene (EDNRA) as a possible molecular target of HT. In summary, we demonstrate that cellular supplementation with HT results in a specific methylome map and propose a potential gene target for HT.

Effect of NETs/COX-2 pathway on immune microenvironment and metastasis in gastric cancer

Background

Neutrophil extracellular traps (NETs) are crucial in the progression of several cancers. The formation of NETs is closely related to reactive oxygen species (ROS), and the granule proteins involved in nucleosome depolymerization under the action of ROS together with the loosened DNA compose the basic structure of NETs. This study aims to investigate the specific mechanisms of NETs promoting gastric cancer metastasis in order to perfect the existing immunotherapy strategies.

Methods

In this study, the cells and tumor tissues of gastric cancer were detected by immunological experiments, real-time polymerase chain reaction and cytology experiments. Besides, bioinformatics analysis was used to analyze the correlation between cyclooxygenase-2 (COX-2) and the immune microenvironment of gastric cancer, as well as its effect on immunotherapy.

Results

Examination of clinical specimens showed that NETs were deposited in tumor tissues of patients with gastric cancer and their expression was significantly correlated with tumor staging. Bioinformatics analysis showed that COX-2 was involved in gastric cancer progression and was associated with immune cell infiltration as well as immunotherapy. In vitro experiments, we demonstrated that NETs could activate COX-2 through Toll-like receptor 2 (TLR2) and thus enhance the metastatic ability of gastric cancer cells. In addition, in a liver metastasis model of nude mice we also demonstrated the critical role of NETs and COX-2 in the distant metastasis of gastric cancer.

Conclusion

NETs can promote gastric cancer metastasis by initiating COX-2 through TLR2, and COX-2 may become a target for gastric cancer immunotherapy.

Phenylboronic Acid-Grafted Chitosan Nanocapsules for Effective Delivery and Controllable Release of Natural Antioxidants: Olive Oil and Hydroxytyrosol

Olives and virgin olive oil (VOO) are a staple of Mediterranean diets and are rich in several beneficial phenolic compounds, including hydroxytyrosol (HT). Therefore, VOO was extracted from Koroneiki olive fruits, and its volatile as well as phenolic components were identified. Meanwhile, in order to upgrade the pharmaceutical capabilities of VOO and HT, a new conjugate phenylboronic acid-chitosan nanoparticles (PBA-CSNPs, NF-1) was fabricated and applied as nanocapsules for implanting high loading and efficient delivery of VOO and HT nanoformulations (NF-2 and NF-3). Due to the H-bonding interactions and boronate ester formation between the hydroxyl groups of the phenolic content of VOO or HT and the PBA groups in the nanocapsules (NF-1), VOO and HT were successfully loaded into the PBA-CSNPs nanocapsules with high loading contents and encapsulation efficacies. The NF-2 and NF-3 nanoformulations demonstrated physicochemical stability, as revealed by their respective zeta potential values, and pH-triggered drug release characteristics. The in vitro studies demonstrated that the nascent nanocapsules were almost completely nontoxic to both healthy and cancer cells, whereas VOO-loaded (NF-2) and HT-loaded nanocapsules (NF-3) showed efficient anti-breast cancer efficiencies. In addition, the antimicrobial and antioxidant potentials of VOO and HT were significantly improved after nanoencapsulation.

Effects of Oleuropein and Hydroxytyrosol on Inflammatory Mediators: Consequences on Inflammaging

Aging is associated with a low-grade, systemic inflammatory state defined as "inflammaging", ruled by the loss of proper regulation of the immune system leading to the accumulation of pro-inflammatory mediators. Such a condition is closely connected to an increased risk of developing chronic diseases. A number of studies demonstrate that olive oil phenolic compound oleuropein and its derivative hydroxytyrosol contribute to modulating tissue inflammation and oxidative stress, thus becoming attractive potential candidates to be used in the context of nutraceutical interventions, in order to ameliorate systemic inflammation in aging subjects. In this review, we aim to summarize the available data about the anti-inflammatory properties of oleuropein and hydroxytyrosol, discussing them in the light of molecular pathways involved in the synthesis and release of inflammatory mediators in inflammaging.

The recovery from agro-industrial wastes provides different profiles of anti-inflammatory polyphenols for tailored applications

Food and agro-industrial processing produce a great amount of side-stream and waste materials that are excellent sources of functional bioactive molecules such as phenolic compounds that recover them can be beneficial not only for food sustainability but also to human for many industrial applications such as flavor compounds and therapeutic applications such as antimicrobial and anti-inflammatory. The treatments and extraction techniques have major effects on the recovery of bioactive compounds. Along with the conventional extraction methods, numerous innovative techniques have been evolved and have been optimized to facilitate bioactive extraction more efficiently and sustainably. In this work, we have summarized the state-of-the-art technological approaches concerning novel extraction methods applied for five most produced crops in Italy; Grape Pomace (GP), Tomato Pomace (TP), Olive Pomace (OP), Citrus Pomace (CP), and Spent Coffee Grounds (SCG), presenting the extraction yield and the main class of phenolic classes, with the focus on their biological activity as an anti-inflammatory in vitro and in vivo studies via describing their molecular mechanism of action.

Maternal Mediterranean Diet Adherence and Its Associations with Maternal Prenatal Stressors and Child Growth

Background

Psychosocial and physiologic stressors, such as depression and obesity, during pregnancy can have negative consequences, such as increased systemic inflammation, contributing to chronic disease for both mothers and their unborn children. These conditions disproportionately affect racial/ethnic minorities. The effects of recommended dietary patterns in mitigating the effects of these stressors remain understudied.

Objectives

We aimed to evaluate the relations between maternal Mediterranean diet adherence (MDA) and maternal and offspring outcomes during the first decade of life in African Americans, Hispanics, and Whites.

Methods

This study included 929 mother-child dyads from the NEST (Newborn Epigenetics STudy), a prospective cohort study. FFQs were used to estimate MDA in pregnant women. Weight and height were measured in children between birth and age 8 y. Multivariable linear regression models were used to examine associations between maternal MDA, inflammatory cytokines, and pregnancy and postnatal outcomes.

Results

More than 55% of White women reported high MDA during the periconceptional period compared with 22% of Hispanic and 18% of African American women (P < 0.05). Higher MDA was associated with lower likelihood of depressive mood (β = -0.45; 95% CI: -0.90, -0.18; P = 0.02) and prepregnancy obesity (β = -0.29; 95% CI: -0.57, -0.0002; P = 0.05). Higher MDA was also associated with lower body size at birth, which was maintained to ages 3-5 and 6-8 y-this association was most apparent in White children (3-5 y: β = -2.9, P = 0.02; 6-8 y: β = -3.99, P = 0.01).

Conclusions

If replicated in larger studies, our data suggest that MDA provides a potent avenue by which effects of prenatal stressors on maternal and fetal outcomes can be mitigated to reduce ethnic disparities in childhood obesity.

In Vitro Anti-Proliferative and Apoptotic Effects of Hydroxytyrosyl Oleate on SH-SY5Y Human Neuroblastoma Cells

The antitumor activity of polyphenols derived from extra virgin olive oil and, in particular the biological activity of HTyr, has been studied extensively. However, the use of HTyr as a therapeutic agent for clinical applications is limited by its low bioavailability and rapid excretion in humans. To overcome these limitations, several synthetic strategies have been optimized to prepare lipophenols and new compounds derived from HTyr to increase lipophilicity and bioavailability. One very promising ester is hydroxytyrosyl oleate (HTyr-OL) because the chemical structure of HTyr, which is responsible for several biological activities, is linked to the monounsaturated chain of oleic acid (OA), giving the compound high lipophilicity and thus bioavailability in the cellular environment. In this study, the in vitro cytotoxic, anti-proliferative, and apoptotic induction activities of HTyr-OL were evaluated against SH-SY5Y human neuroblastoma cells, and the effects were compared with those of HTyr and OA. The results showed that the biological activity of HTyr was maintained in HTyr-OL treatments at lower dosages. In addition, the shotgun proteomic approach was used to study HTyr-OL-treated and untreated neuroblastoma cells, revealing that the antioxidant, anti-proliferative and anti-inflammatory activities of HTyr-OL were observed in the unique proteins of the two groups of samples.

Thermo-Responsive Gel Containing Hydroxytyrosol-Chitosan Nanoparticles (Hyt@tgel) Counteracts the Increase of Osteoarthritis Biomarkers in Human Chondrocytes

Although osteoarthritis (OA) is a chronic inflammatory degenerative disease affecting millions of people worldwide, the current therapies are limited to palliative care and do not eliminate the necessity of surgical intervention in the most severe cases. Several dietary and nutraceutical factors, such as hydroxytyrosol (Hyt), have demonstrated beneficial effects in the prevention or treatment of OA both in vitro and in animal models. However, the therapeutic application of Hyt is limited due to its poor bioavailability following oral administration. In the present study, a localized drug delivery platform containing a combination of Hyt-loading chitosan nanoparticles (Hyt-NPs) and in situ forming hydrogel have been developed to obtain the benefits of both hydrogels and nanoparticles. This thermosensitive formulation, based on Pluronic F-127 (F-127), hyaluronic acid (HA) and Hyt-NPs (called Hyt@tgel) presents the unique ability to be injected in a minimally invasive way into a target region as a freely flowing solution at room temperature forming a gel at body temperature. The Hyt@tgel system showed reduced oxidative and inflammatory effects in the chondrocyte cellular model as well as a reduction in senescent cells after induction with H₂O₂. In addition, Hyt@tgel influenced chondrocytes gene expression under pathological state maintaining their metabolic activity and limiting the expression of critical OA-related genes in human chondrocytes treated with stressors promoting OA-like features. Hence, it can be concluded that the formulated hydrogel injection could be proposed for the efficient and sustained Hyt delivery for OA treatment. The next step would be the extraction of “added-value” bioactive polyphenols from by-products of the olive industry, in order to develop a green delivery system able not only to enhance the human wellbeing but also to promote a sustainable environment.

Recovery of hydroxytyrosol from olive mill wastewater using the promiscuous hydrolase/acyltransferase PestE

Olive mill wastewater (OMWW) is produced annually during olive oil extraction and contains most of the health‐promoting 3‐hydroxytyrosol of the olive fruit. To facilitate its recovery, enzymatic transesterification of hydroxytyrosol (HT) was directly performed in an aqueous system in the presence of ethyl acetate, yielding a 3‐hydroxytyrosol acetate rich extract. For this, the promiscuous acyltransferase from Pyrobaculum calidifontis VA1 (PestE) was engineered by rational design. The best mutant for the acetylation of hydroxytyrosol (PestE_I208A_L209F_N288A) was immobilized on EziG² beads, resulting in hydroxytyrosol conversions between 82 and 89 % in one hour, for at least ten reaction cycles in a buffered hydroxytyrosol solution. Due to inhibition by other phenols in OMWW the conversions of hydroxytyrosol from this source were between 51 and 62 %. In a preparative scale reaction, 13.8 mg (57 %) of 3‐hydroxytyrosol acetate was extracted from 60 mL OMWW.

Anti-Inflammatory Effects Induced by a Polyphenolic Granular Complex from Olive (Olea europaea, Mainly Cultivar coratina): Results from In Vivo and Ex Vivo Studies in a Model of Inflammation and MIA-Induced Osteoarthritis

MOMAST^® GR25 is a polyphenolic granular complex from olive pressing juice with high total content in polyphenols. In this work, we evaluated the possible anti-inflammatory effects of MOMAST^® GR25 in both acute and chronic inflammatory models. MOMAST^® GR25 decreased the levels of prostaglandin (PG) E₂ and 8-iso-PGF_2α in isolated rat colon, liver, and heart specimens stimulated with lipopolysaccharide (LPS). In vivo, compared to controls, rats treated with MOMAST^® GR25 (100 mg/kg to 1 g/kg) showed a significant reduction in both licking/biting time in the formalin test. In a rat model of osteoarthritis by monoiodoacetate (MIA) injection, MOMAST^® GR25 showed pain-relieving properties when acutely administered, reducing mechanical hyperalgesia and spontaneous pain. Moreover, a repeated daily treatment with MOMAST^® GR25 (300 mg/kg) fully counteracted osteoarticular pain without the development of tolerance to the antinociceptive effect. Taken together, our present findings showed that MOMAST^® GR25 could represent a potential strategy for the treatment of inflammation and pain.

State of knowledge on chemical, biological and nutritional properties of olive mill wastewater

The Mediterranean olive oil industries are producing annually a massive quantity of olive mill wastewater (OMWW). Unfortunately, the OMWW is released arbitrarily in the nature without any pretreatment. Thus, it exhibits a high toxicity against the whole natural ecosystem including, microorganisms, plants and animals. In order to eliminate or reduce its pollution, OMWW must be properly treated prior to its release in the nature. In this regard, different treatment methods have been developed by researchers, but some of them were costly and others were inappropriate. Thus, more efforts should be made to save the nature from this pollutant. In the light of that, the current work summaries the state of knowledge regarding the OMWW from a chemical, biological, nutraceutical point of view, and the treatment methods that were used to eliminate its risk of pollution.

3,4-Dihydroxyphenylethanol ameliorates lipopolysaccharide-induced septic cardiac injury in a murine model

3,4-Dihydroxyphenylethanol (DOPET) is a polyphenol found in olive oil. The present study evaluated the protective role of DOPET on LPS provoked septic cardiac injury in a murine model. Four groups were used in the study (n = 3): control, LPS, DOPET alone, and DOPET + LPS. LPS (15 mg/kg; i.p.); they were used to induce cardiac sepsis. The cardiac markers like LDH, CK-MB, and troponin-T, as well as inflammatory cytokines like TNF-α and IL-6 were measured in the serum. The antioxidants and oxidative stress parameters were measured in cardiac tissues. RT-PCR and western blot methods were done to evaluate the expression of inflammatory mediators and apoptotic markers. DOPET significantly decreased the cardiac markers (LDH, CK-MB, and troponin-T) and TNF-α and IL-6 level in the serum. DOPET effectively reduced the levels of MDA and NO in LPS intoxicated rats. DOPET also increased the levels of antioxidants like SOD, CAT, GPx, and GSH in LPS intoxicated rats. The mRNA levels of TNF-α, IL-6, and NF-κB were significantly downregulated by DOPET in cardiac tissues of LPS rats. The protein expression of Bcl-2 was upregulated, and Bax and caspase-3 were downregulated by DOPET. DOPET effectively attenuates LPS-induced cardiac dysfunction through its antioxidant, anti-inflammatory, and anti-apoptotic mechanisms.

Niosomal formulation of hydroxytyrosol, a polyphenolic antioxidant, for enhancing transdermal delivery across human cadaver skin

Hydroxytyrosol (HT), a naturally occurring polyphenol from the olive plant, is a potent antioxidant, cardioprotective, neuroprotective, and anti-inflammatory agent. Upon oral administration, HT undergoes rapid elimination within minutes and thus limiting its therapeutic utility. Due to its hydrophilic nature, percutaneous absorption and transdermal delivery of HT are very low. The aim of this research was to enhance the skin permeation of hydroxytyrosol using a niosome gel formulation. The formulations prepared with Span 60 as surfactant showed uniform particle size and high encapsulation efficiency (>90%). The niosome formulations showed a pseudoplastic behavior for topical application within the lipid/surfactant composition of 45-50%. The formulations showed a controlled release of HT compared to the HT solution. The flux of HT across human skin was increased by 28 and 4.4 fold compared to aqueous and ethanolic HT solutions, respectively (p < 0.001). The presence of lecithin lowered the flux and increased the retention of the formulations compared to HT solutions (p < 0.001). The formulations containing lecithin showed two-fold higher skin retention of hydroxytyrosol (p < 0.05). In conclusion, this study demonstrates niosome gel as a promising alternative to oral delivery of HT, providing sustained delivery and greater efficacy.

Emerging nanoformulation strategies for phytocompounds and applications from drug delivery to phototherapy to imaging

Over thousands of years, natural bioactive compounds derived from plants (bioactive phytocompounds, BPCs) have been used worldwide to address human health issues. Today, they are a significant resource for drug discovery in the development of modern medicines. Although many BPCs have promising biological activities, most of them cannot be effectively utilized in drugs for therapeutic applications because of their inherent limitations of low solubility, structural instability, short half-life, poor bioavailability, and non-specific distribution to organs. Researchers have utilized emerging nanoformulation (NF) technologies to overcome these limitations as they have demonstrated great potential to improve the solubility, stability, and pharmacokinetic and pharmacodynamic characteristics of BPCs. This review exemplifies NF strategies for resolving the issues associated with BPCs and summarizes recent advances in their preclinical and clinical applications for imaging and therapy. This review also highlights how innovative NF technologies play a leading role in next-generation BPC-based drug development for extended therapeutic applications. Finally, this review discusses the opportunities to take BPCs with meaningful clinical impact from bench to bedside and extend the patent life of BPC-based medicines with new formulations or application to new adjacent diseases beyond the primary drug indications.

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Natural bioactive phytocompounds derived from plants have been used worldwide to address human health issues. However, most of them cannot be effectively utilized in drugs for therapeutic applications because of their inherent limitations.

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Nanoformulation approach has recently been underlined as an emerging pharmaceutical strategy to overcome the intrinsic drawbacks of bioactive phytocompounds.

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Various types of nanoformulation and their up-to-date applications for targeted delivery, phototherapy, and imaging are reviewed. Finally, their clinical implications for the repurposing of bioactive phytocompounds are deliberated.

Effects of Oleuropein on Epirubicin and Cyclophosphamide Combination Treatment in Rats

Objectives

Oleuropein is the main bioactive polyphenolic compound in olive leaves, olive, and olive oil. Its anticancer, antioxidant, and antiinflammatory effects have been proven through several in vitro and in vivo studies. This study aimed to explore the effects of oleuropein on cyclophosphamideand epirubicin-induced toxicity in female rats.

Materials and Methods

Seven groups containing eight rats in each group were formed. Four cycles of 16 mg/kg/week of cyclophosphamide and 2.5 mg/kg/week of epirubicin were administered to the rats through intraperitoneal injection. Oleuropein (150 mg/kg/week) was simultaneously applied via oral gavage. The effects of oleuropein were examined with hemogram tests in whole blood samples and biochemical analysis in serum samples. Interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in the serum samples were analyzed through enzyme-linked immunosorbent assay. Subsequently, a comet assay was performed using lymphocyte DNA. The levels of oxidant [i.e., malondialdehyde (MDA)] and antioxidants [i.e., catalase (CAT), glutathione (GSH), and superoxide dismutase (SOD)] were measured in the heart, kidney, and liver tissues.

Results

Oleuropein could reduce DNA damage and serum TNF-α and IL-6 levels. It also ameliorated some hemogram and biochemical parameters that deteriorated due to antineoplastic drugs. It increased the amounts of antioxidants (GSH, SOD, and CAT) and reduced the level of MDA in the heart, kidney, and liver tissues.

Conclusion

Oleuropein might be a beneficial agent against toxicity caused by the combination treatment of cyclophosphamide and epirubicin. Further studies should be performed to demonstrate the protective effects of oleuropein against antineoplastic induced-toxicity precisely.

Anti-inflammatory activity of Jasminum grandiflorum L. subsp. floribundum (Oleaceae) in inflammatory bowel disease and arthritis models

Our study has renewed interest in the genus Jasmine for the treatment of chronic inflammatory conditions. Aerial parts of Jasminum grandiflorum L. subsp. floribundum total methanolic extract (JTME) were tested for its therapeutic potential as an anti-inflammatory agent using two experimental models in rats; acetic acid (AA) induced ulcerative colitis and adjuvant induced arthritis. The administration of JTME showed anti-inflammatory activity in a dose dependent manner. JTME, 400 mg/kg was like prednisolone, 2 mg/kg p.o. (the reference drug), since it improved the tissues of the colon clinically, macro and microscopically (ulcer index), and histopathological (scoring). It reduced the intestinal expression of pro-inflammatory cytokines in the colonic mucosa; IFNγ, TNFα, IL-6, IL-1, and MPO. It also preserved tight junctions in intestinal epithelial cells by counter-regulating claudin-5 and occludin levels additionally, it had a potent antioxidant activity. The expressions of NF-κB p65, TNF-α and caspase-3 in rats administered AA (2 mL of 4% solution, once, intrarectally) were significantly increased, where the lowest expression was scored in JTME, 400 mg/kg group. In the adjuvant induced model of rheumatoid arthritis, the TJME, 400 mg/kg reduced the levels of cathepsin D, iNOS, NO, RF, CRP, CPP and elevated the total antioxidant capacity of tissues. Additionally, it maintained bones without histopathological lesions, articular cartilage damage, and inflammation of the synovial membrane and periarticular tissues, in contrast to arthritic rats. Finally, we report a new detailed study to validate the medicinal importance of Jasminum for the chronic inflammatory disorders with immune dysfunction with anti-inflammatory and antioxidant effects.

Olive Polyphenols: Antioxidant and Anti-Inflammatory Properties

Oxidative stress and inflammation triggered by increased oxidative stress are the cause of many chronic diseases. The lack of anti-inflammatory drugs without side-effects has stimulated the search for new active substances. Plant-derived compounds provide new potential anti-inflammatory and antioxidant molecules. Natural products are structurally optimized by evolution to serve particular biological functions, including the regulation of endogenous defense mechanisms and interaction with other organisms. This property explains their relevance for infectious diseases and cancer. Recently, among the various natural substances, polyphenols from extra virgin olive oil (EVOO), an important element of the Mediterranean diet, have aroused growing interest. Extensive studies have shown the potent therapeutic effects of these bioactive molecules against a series of chronic diseases, such as cardiovascular diseases, diabetes, neurodegenerative disorders and cancer. This review begins from the chemical structure, abundance and bioavailability of the main EVOO polyphenols to highlight the effects and the possible molecular mechanism(s) of action of these compounds against inflammation and oxidation, in vitro and in vivo. In addition, the mechanisms of inhibition of molecular signaling pathways activated by oxidative stress by EVOO polyphenols are discussed, together with their possible roles in inflammation-mediated chronic disorders, also taking into account meta-analysis of population studies and clinical trials.

Molecular Action of Hydroxytyrosol in Attenuation of Intimal Hyperplasia: A Scoping Review

Objective: Hydroxytyrosol (HT), a polyphenol of olive plant is well known for its antioxidant, anti-inflammatory and anti-atherogenic properties. The aim of this systematic search is to highlight the scientific evidence evaluating molecular efficiency of HT in halting the progression of intimal hyperplasia (IH), which is a clinical condition arises from endothelial inflammation.

Methods: A systematic search was performed through PubMed, Web of Science and Scopus, based on pre-set keywords which are Hydroxytyrosol OR 3,4-dihydroxyphenylethanol, AND Intimal hyperplasia OR Neointimal hyperplasia OR Endothelial OR Smooth muscles. Eighteen in vitro and three in vitro and in vivo studies were selected based on a pre-set inclusion and exclusion criteria.

Results: Based on evidence gathered, HT was found to upregulate PI3K/AKT/mTOR pathways and supresses inflammatory factors and mediators such as IL-1β, IL-6, E-selectin, P-selectin, VCAM-1, and ICAM-1 in endothelial vascularization and functioning. Two studies revealed HT disrupted vascular smooth muscle cells (SMC) cell cycle by dephosphorylating ERK1/2 and AKT pathways. Therefore, HT was proven to promote endothelization and inhibit vascular SMCs migration thus hampering IH development. However, none of these studies described the effect of HT collectively in both vascular endothelial cells (EC) and SMCs in IH ex vivo model.

Conclusions: Evidence from this concise review provides an insight on HT regulation of molecular pathways in reendothelization and inhibition of VSMCs migration. Henceforth, we propose effect of HT on IH prevention could be further elucidated through in vivo and ex vivo model.

Olive Fruit Extracts Supplement Improve Antioxidant Capacity via Altering Colonic Microbiota Composition in Mice

Oxidative stress, one of the most common biological dysfunctions, is usually associated with pathological conditions and multiple diseases in humans and animals. Chinese olive fruit (Canarium album L.) extracts (OE) are natural plant extracts rich in polyphenols (such as hydroxytyrosol, HT) and with antioxidant, anti-hyperlipidemia, and anti-inflammatory potentials. This study was conducted to investigate the antioxidant capacity of OE supplementation and its related molecular mechanism in mice. Mice (25.46 ± 1.65 g) were treated with 100 mg/kg body weight (BW) OE or saline solution for 4 weeks, and then the antioxidant and anti-inflammatory capacities of mice were examined. The results showed that OE supplement significantly increased the serum antioxidative enzyme activities of total antioxidant activity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase and decreased the serum malondialdehyde (MDA) level, indicating that OE treatment enhanced the antioxidant capacity in mice. qPCR results showed that the transcriptional expression of antioxidant SOD1, CAT, Gpx1, and Gpx2 were significantly down-regulated in the small intestine (jejunum and ileum) after OE administration. Meanwhile, OE treatment significantly decreased the T-AOC and increased the MDA level in the small intestine. Furthermore, OE administration dramatically reduced the mRNA expression of pro-inflammatory cytokines (TNF-α and IL-1β), which confirmed its antioxidant and anti-inflammatory capacities with OE administration. Using amplicon sequencing technology, 16S rRNA sequencing results showed that OE supplement significantly increased the colonic Firmicutes/Bacteroidetes ratio, which also had a negative correlation with the serum MDA level and positively correlated with serum GSH-Px activity through Pearson correlation analysis. Besides that, Alloprevotella was negatively correlated with serum T-AOC. Colidextribacter was positively correlated with serum MDA and negatively correlated with serum T-AOC, SOD, and GSH-Px levels. In summary, this study showed that treatment with 100 mg/kg BW polyphenol-rich OE could alter colonic microbiota community, which was strongly associated with improved antioxidant capacity in mice.

Investigations of Olive Oil Industry By-Products Extracts with Potential Skin Benefits in Topical Formulations

The by-products of olive oil industry are a major ecological issue due to their phenolic content, highly toxic organic load, and low pH. However, they can be recovered and reused, since their components have antioxidant, anti-inflammatory, and photoprotector properties. In this work, oil-in-water creams containing three different olive oil industry by-products extracts were produced without the use of organic solvents. First, the extracts were thoroughly characterized in vitro for cytotoxicity, inhibition of skin enzymes, and antioxidant and photoprotection capacities. Safety studies were then performed, including ocular and skin irritation tests, ecotoxicity evaluation, and in vivo Human Repeat Insult Patch Test. The results obtained in this initial characterization supported the incorporation of the extracts in the cream formulations. After preparation, the creams were characterized for their organoleptic, physicochemical, droplet size and rheological properties, and microbial contamination. The results showed that all formulations were semi-solid creams, with stable pH, compatible with the skin, without microbial contamination, and with the expected droplet size range. The rheological analysis showed shear-thinning behavior with yield stress, with the viscosity decreasing with increasing shear rate. The oscillatory results suggest that the creams have a strong network structure, being easily rubbed into the skin. Finally, compatibility, acceptability and antioxidant efficacy were evaluated in vivo, in human volunteers. No adverse reactions were observed after application of the formulations on skin and the cream with the highest concentrations of phenolic compounds showed the highest antioxidant efficiency. In conclusion, the results suggest that olive oil industry by-products extracts have valuable properties that favor their re-use in the cosmetic industry. The example presented here showed their successful incorporation into creams and their impact in these formulations' appearance, pH, and rheological performance, as well as their in vivo compatibility with skin and antioxidant efficiency.

Graphene-Based Sensors for the Detection of Bioactive Compounds: A Review

Over the last years, different nanomaterials have been investigated to design highly selective and sensitive sensors, reaching nano/picomolar concentrations of biomolecules, which is crucial for medical sciences and the healthcare industry in order to assess physiological and metabolic parameters. The discovery of graphene (G) has unexpectedly impulsed research on developing cost-effective electrode materials owed to its unique physical and chemical properties, including high specific surface area, elevated carrier mobility, exceptional electrical and thermal conductivity, strong stiffness and strength combined with flexibility and optical transparency. G and its derivatives, including graphene oxide (GO) and reduced graphene oxide (rGO), are becoming an important class of nanomaterials in the area of optical and electrochemical sensors. The presence of oxygenated functional groups makes GO nanosheets amphiphilic, facilitating chemical functionalization. G-based nanomaterials can be easily combined with different types of inorganic nanoparticles, including metals and metal oxides, quantum dots, organic polymers, and biomolecules, to yield a wide range of nanocomposites with enhanced sensitivity for sensor applications. This review provides an overview of recent research on G-based nanocomposites for the detection of bioactive compounds, providing insights on the unique advantages offered by G and its derivatives. Their synthesis process, functionalization routes, and main properties are summarized, and the main challenges are also discussed. The antioxidants selected for this review are melatonin, gallic acid, tannic acid, resveratrol, oleuropein, hydroxytyrosol, tocopherol, ascorbic acid, and curcumin. They were chosen owed to their beneficial properties for human health, including antibiotic, antiviral, cardiovascular protector, anticancer, anti-inflammatory, cytoprotective, neuroprotective, antiageing, antidegenerative, and antiallergic capacity. The sensitivity and selectivity of G-based electrochemical and fluorescent sensors are also examined. Finally, the future outlook for the development of G-based sensors for this type of biocompounds is outlined.

Natural Bioactive Compounds Useful in Clinical Management of Metabolic Syndrome

Metabolic syndrome (MetS) is a clinical manifestation characterized by a plethora of comorbidities, including hyperglycemia, abdominal obesity, arterial hypertension, and dyslipidemia. All MetS comorbidities participate to induce a low-grade inflammation state and oxidative stress, typical of this syndrome. MetS is related to an increased risk of cardiovascular diseases and early death, with an important impact on health-care costs. For its clinic management a poly-pharmaceutical therapy is often required, but this can cause side effects and reduce the patient's compliance. For this reason, finding a valid and alternative therapeutic strategy, natural and free of side effects, could represent a useful tool in the fight the MetS. In this context, the use of functional foods, and the assumption of natural bioactive compounds (NBCs), could exert beneficial effects on body weight, blood pressure and glucose metabolism control, on endothelial damage, on the improvement of lipid profile, on the inflammatory state, and on oxidative stress. This review focuses on the possible beneficial role of NBCs in the prevention and in the clinical management of MetS and its comorbidities.

Impact of hydroxytyrosol on stroke: tracking therapy response on neuroinflammation and cerebrovascular parameters using PET-MR imaging and on functional outcomes

Immune cells have been implicated in influencing stroke outcomes depending on their temporal dynamics, number, and spatial distribution after ischemia. Depending on their activation status, immune cells can have detrimental and beneficial properties on tissue outcome after stroke, highlighting the need to modulate inflammation towards beneficial and restorative immune responses. Novel dietary therapies may promote modulation of pro- and anti-inflammatory immune cell functions. Among the dietary interventions inspired by the Mediterranean diet, hydroxytyrosol (HT), the main phenolic component of the extra virgin olive oil (EVOO), has been suggested to have antioxidant and anti-inflammatory properties in vitro. However, immunomodulatory effects of HT have not yet been studied in vivo after stroke. The aim of this project is therefore to monitor the therapeutic effect of a HT-enriched diet in an experimental stroke model using non-invasive in vivo multimodal imaging, behavioural phenotyping and cross-correlation with ex vivo parameters. Methods: A total of N = 22 male C57BL/6 mice were fed with either a standard chow (n = 11) or a HT enriched diet (n = 11) for 35 days, following a 30 min transient middle cerebral artery occlusion (tMCAo). T₂-weighted (lesion) and perfusion (cerebral blood flow)-/diffusion (cellular density)-weighted MR images were acquired at days 1, 3, 7, 14, 21 and 30 post ischemia. [¹⁸F]DPA-714 (TSPO, neuroinflammation marker) PET-CT scans were acquired at days 7, 14, 21 and 30 post ischemia. Infarct volume (mm³), cerebral blood flow (mL/100g/min), apparent diffusion coefficient (10^-4·mm²/s) and percentage of injected tracer dose (%ID/mL) were assessed. Behavioural tests (grip test, rotarod, open field, pole test) were performed prior and after ischemia to access therapy effects on sensorimotor functions. Ex vivo analyses (IHC, IF, WB) were performed to quantify TSPO expression, immune cells including microglia/macrophages (Iba-1, F4/80), astrocytes (GFAP) and peripheral markers in serum such as thiobarbituric acid reactive substances (TBARS) and nitric oxide (NO) 35 days post ischemia. Additionally, gene expression of pro- and anti-inflammatory markers were assessed by rt-qPCR, including tspo, cd163, arg1, tnf and Il-1β. Results: No treatment effect was observed on temporal [¹⁸F]DPA-714 uptake within the ischemic and contralateral region (two-way RM ANOVA, p = 0.71). Quantification of the percentage of TSPO⁺ area by immunoreactivity indicated a slight 2-fold increase in TSPO expression within the infarct region in HT-fed mice at day 35 post ischemia (p = 0.011) correlating with a 2-3 fold increase in Iba-1⁺ cell population expressing CD163 as anti-inflammatory marker (R² = 0.80). Most of the GFAP⁺ cells were TSPO^-. Only few F4/80⁺ cells were observed at day 35 post ischemia in both groups. No significant treatment effect was observed on global ADC and CBF within the infarct and the contralateral region over time. Behavioural tests indicated improved strength of the forepaws at day 14 post ischemia (p = 0.031). Conclusion: An HT-enriched diet significantly increased the number of Iba-1⁺ microglia/macrophages in the post-ischemic area, inducing higher expression of anti-inflammatory markers while no clear-cut effect was observed. Also, HT did not affect recovery of the cerebrovascular parameters, including ADC and CBF. Altogether, our data indicated that a prolonged dietary intervention with HT, as a single component of the Mediterranean diet, induces molecular changes that may improve stroke outcomes. Therefore, we support the use of the Mediterranean diet as a multicomponent therapy approach after stroke.

Application of Hydroxytyrosol in the Functional Foods Field: From Ingredient to Dietary Supplements

Hydroxytyrosol (HT) is an amphipathic functional phenol found in the olive tree, both in its leaves and fruits, in free or bound forms, as well as in olive oil and by-products of olive oil manufacture. The European Food Safety Authority recommends regular consumption of HT due to its several beneficial effects on human health, which are closely associated to its antioxidant activity. These reasons make HT an excellent candidate for application as a functional ingredient in the design of novel food products. Patents already exist for methodologies of extraction, purification, and application of HT in supplements and food products. The present review discusses the impact of HT incorporation on food properties and its effects on consumers, based on relevant data related to the use of HT as a functional ingredient, both as a pure compound or in the form of HT-rich extracts, in various food products, namely in edible oils, beverages, bakery products, as well animal-based foods such as meat, fishery and dairy products.

Functional Metabolomics Analysis Elucidating the Metabolic Biomarker and Key Pathway Change Associated With the Chronic Glomerulonephritis and Revealing Action Mechanism of Rhein

Chronic glomerulonephritis (CGN) as the culprit of kidney failure can increase the mortality of critically ill patients and seriously threatens people’s health all over the world. This study using metabolomics strategy is to reveal the potential therapeutic mechanism-related targets to evaluate the effects of rhein (RH) on CGN rats. Changes of serum metabolites and pathways were analyzed by non-targeted metabolomic method based on liquid chromatography-mass spectrometry (LC-MS) combined with ingenuity pathway analysis. In addition, the levels of biochemical indicators were also detected. A total of 25 potential biomarkers were identified to express serum metabolic turbulence in CGN animal model, and then 16 biomarkers were regulated by RH trending to the normal states. From metabolite enrichment and pathway analysis, pharmacological activity of RH on CGN were mainly involved in six vital metabolic pathways including phenylalanine, tyrosine and tryptophan biosynthesis, phenylalanine metabolism, arachidonic acid metabolism, tricarboxylic acid cycle (TCA cycle), alanine, aspartate, and glutamate metabolism, arginine and proline metabolism. It suggested CGN treatment with RH, which may be mediated via interference with metabolic pathway such as amino acid metabolism, arachidonic acid metabolism, and TCA cycle to regulating inflammation, oxidation response and immune regulation against CGN. It showed that metabolomics method offer deeply insight into the therapeutic mechanisms of natural product.

Protective Effect of Hydroxytyrosol on LPS-Induced Inflammation and Oxidative Stress in Bovine Endometrial Epithelial Cell Line

Bovine endometritis is a serious pathogen-induced infectious disease that affects the physiological processes of estrus, pregnancy and the postpartum condition. The inflamed endometrium responds by activating an inflammatory intracellular signaling cascade that leads to increased expression of proinflammatory cytokines and reactive oxygen species (ROS). Oxidative stress is closely related to several pathological conditions in perinatal dairy cows and play a key role in tissue damage. Hydroxytyrosol (HT), a natural phenolic alcohol with a strong antioxidant activity, displayed a wide range of biological effect. The aim of this study was to evaluate the protective effects of HT in an in vitro model of lipopolysaccharide (LPS)-induced inflammation in bovine uterine endometrial cells. Our results showed that HT had a significant protective effect in LPS-induced inflammation and oxidative stress. HT was also able to increase the capacity of endogenous antioxidant systems through the up-regulation of the NRF2 pathway. Furthermore, HT restored the tight junction protein expressions. In conclusion, our results showed the protective effects of HT in LPS-stimulated BEND cells. Therefore, the results of this study suggest an important protective role of HT in the treatment and prevention of uterine pathologies in dairy cows.

Potential Beneficial Effects of Extra Virgin Olive Oils Characterized by High Content in Minor Polar Compounds in Nephropathic Patients: A Pilot Study

Extra virgin olive oil (EVOO) is a lipid food, which constitutes a pillar of the Mediterranean diet. A high number of scientific data have demonstrated that it exerts a variety of beneficial effects on human health due to its peculiar chemical composition including fatty acids (98–99%) and other active compounds even if found in a very low percentage (1–2%). Among them, minor polar compounds (MCPs), represented mainly by phenolic compounds, are relevant for their healthy properties, as stated by the European Food Safety Authority’s (EFSA) claims. In this paper, we described the results obtained from a pilot in vivo study, focused for the first time on the evaluation of the possible beneficial effects of two EVOOs on chronic kidney disease (CKD) patients after the consumption of 40 mL per day for 9 weeks. The selected EVOOs, traced in the production chain, and characterized by High-Performance Liquid Chromatography (HPLC-DAD-MS) analysis, resulted rich in MCPs and satisfied the EFSA’s claim for their content of hydroxytyrosol and derivatives. The results obtained by this in vivo study appear to highlight the potential beneficial role in CKD patients of these EVOOs and are promising for future studies.

Supplementation Effect of a Combination of Olive (Olea europea L.) Leaf and Fruit Extracts in the Clinical Management of Hypertension and Metabolic Syndrome

BACKGROUND

The role of herbal products in the prevention of cardiovascular disease requires supporting evidence. This open pilot study assessed the effect of 2-month supplementation of a combination of olive leaf and fruit extracts (Tensiofytol^®, Tilman SA, Baillonville, Belgium) in the clinical management of hypertension and metabolic syndrome (MetS).

METHODS

A total of 663 (pre)-hypertensive patients were enrolled by general practitioners and supplemented for two months with Tensiofytol^®, two capsules per day (100 mg/d of oleuropein and 20 mg/d of hydroxytyrosol). Systolic and diastolic blood pressures (SBP/DBP) were measured before and after treatment. Markers of MetS, high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), fasting blood glucose (FG) and waist circumference (WC), were also examined.

RESULTS

Significant reductions (p < 0.0001) in SBP/DBP (13 ± 10/7.1 ± 6.6 mmHg) were observed and similarly in pre-diabetic and diabetic patients. Improvements in SBP/DPB were independent of age and gender but greater for elevated baseline SBP/DBP. Tensiofytol^® supplementation also significantly improved markers of MetS, with a decrease of TG (11%), WC (1.4%) and FG (4.8%) and an increase of HDL-C (5.3%). Minor side effects were reported in 3.2% patients.

CONCLUSIONS

This real-life, observational, non-controlled, non-randomized pilot study shows that supplementation of a combination of olive leaf and fruit extracts may be used efficiently and safely in reducing hypertension and MetS markers.

Hydroxytyrosol ameliorates oxidative challenge and inflammatory response associated with lipopolysaccharide-mediated sepsis in mice

Hydroxytyrosol (HT) is among the main bioactive ingredients isolated from olive tree with a variety of biological and pharmacological activities. In the current study, the antioxidative and anti-inflammatory activities of HT were distinguished in the splenic tissue following lipopolysaccharide (LPS)-mediated septic response. Thirty-five Swiss mice were divided into five groups (n = 7): control, HT (40 mg/kg), LPS (10 mg/kg), HT 20 mg+LPS and HT 40 mg+LPS. HT was administered for 10 days, while a single LPS dose was applied. The obtained findings demonstrate that HT administration enhanced the survival rate and decreased lactate dehydrogenase level in LPS-challenged mice. Treatment with HT inhibited the incidence of oxidative damage in splenic tissue through decreasing lipoperoxidation and increasing antioxidant molecules, namely glutathione, superoxide dismutase and catalase. HT also decreased total leukocytes count, C-reactive protein, monocyte chemoattractant protein-1, and myeloperoxidase levels. Additionally, HT suppressed the production levels of tumor necrosis factor-α, interleukin-1β, and interleukin-6. Moreover, mRNA expression of inducible nitric oxide synthase and nitric oxide production were increased after HT administration. Furthermore, HT supplementation resulted in a downregulation of p38 mitogen-activated protein kinase, inhibited the activation of the nuclear factor kappa-B from the nucleus to the cytoplasm, and attenuated infiltration of activated immune cells and tissue injury following LPS injection. Collectively, these findings demonstrate the antioxidative and anti-inflammatory properties of HT against LPS-mediated inflammation and sepsis. Therefore, HT could be applied as an alternative anti-inflammatory agent to minimize or prevent the development of systemic inflammatory response associated with septic shock.

An Industrial and Sustainable Platform for the Production of Bioactive Micronized Powders and Extracts Enriched in Polyphenols From Olea europaea L. and Vitis vinifera L. Wastes

In the last few years, literature data have reported that health status is related to the consumption of foods rich in polyphenols, bioactive compounds found in the plant world, in particular in vegetables and fruit. These pieces of scientific evidence have led to an increase in the demand for functional foods and drinks enriched in polyphenols, so that plant materials are more and more requested. The availability of food and agricultural wastes has adverse effects on the economy, environment, and human health. On the other hand, these materials are a precious source of bioactive compounds as polyphenols. Their recovery and reuse from wastes are according to the circular economy strategy, which has introduced the “zero waste concept.” However, the process is convenient from an economic and environmental point of view only if the final products are standardized and obtained using sustainable and industrial technologies. In this panorama, this paper describes an industrial and sustainable platform for the production of micronized powders and extracts enriched in polyphenols from Olea europaea L. and Vitis vinifera L. wastes that are useful for food, cosmetics, and pharmaceuticals sectors. The platform is based on drying plant materials, extraction of polyphenols through membrane technologies with water, and, when necessary, the concentration of the final fractions under vacuum evaporation. All powders and extracts were characterized by high-performance liquid chromatography–diode array detector–mass spectrometry analysis to define the qualitative and quantitative content of bioactive compounds and insure their standardization and reproducibility. The chromatographic profiles evidenced the presence of secoiridoids, flavones, flavonols, anthocyanins, hydroxycinnamic acids, catechins, and condensed tannins. An overview of the biological activities of the main polyphenols present in Olea europaea L. and Vitis vinifera L. powders and extracts is reported because of biomedical applications.

Hydroxytyrosol as a Promising Ally in the Treatment of Fibromyalgia

Fibromyalgia (FM) is a chronic and highly disabling syndrome, which is still underdiagnosed, with controversial treatment. Although its aetiology is unknown, a number of studies have pointed to the involvement of altered mitochondrial metabolism, increased oxidative stress and inflammation. The intake of extra virgin olive oil, and particularly of one of its phenolic compounds, hydroxytyrosol (HT), has proven to be protective in terms of redox homeostatic balance and the reduction of inflammation. In this context, using a proteomic approach with nanoscale liquid chromatography coupled to tandem mass spectrometry, the present study analysed: (i) Changes in the proteome of dermal fibroblasts from a patient with FM versus a healthy control, and (ii) the effect of the treatment with a nutritional relevant dose of HT. Our results unveiled that fibroblast from FM show a differential expression in proteins involved in the turnover of extracellular matrix and oxidative metabolism that could explain the inflammatory status of these patients. Moreover, a number of these proteins results normalized by the treatment with HT. In conclusion, our results support that an HT-enriched diet could be highly beneficial in the management of FM.

Effects of Hydroxytyrosol against Lipopolysaccharide-Induced Inflammation and Oxidative Stress in Bovine Mammary Epithelial Cells: A Natural Therapeutic Tool for Bovine Mastitis

Background: Bovine mastitis is a growing health problem, affecting both welfare of dairy cattle and milk production. It often leads to chronic infections, disturbing the quality of milk and resulting in cow death. Thus, it has a great economic impact for breeders. Methods: In this study, we evaluated the protective effect of hydroxytyrosol—a natural molecule which is the major constituent of many phyto-complexes—in an in vitro model of mastitis induced by LPS (1μg/mL). Results: Our results showed that hydroxytyrosol (10 and 25 μM) was able to prevent the oxidative stress induced by LPS (intracellular ROS, GSH and NOX-1) and the consequently inflammatory response (TNF-α, IL-1β and IL-6). The protective effect of hydroxytyrosol is also related to the enhancement of endogenous antioxidant systems (Nrf2, HO-1, NQO-1 and Txnrd1). Moreover, hydroxytyrosol showed an important protective effect on cell functionality (α-casein S1, α-casein S2 and β-casein). Conclusions: Taken together, our results showed a significant protective effect of hydroxytyrosol on oxidative stress and inflammatory response in MAC-T cells. Thus, we indicated a possible important therapeutic role for hydroxytyrosol in the prevention or management of bovine mastitis.

Olive Mill Wastewater Polyphenol-Enriched Fractions by Integrated Membrane Process: A Promising Source of Antioxidant, Hypolipidemic and Hypoglycaemic Compounds

The valorisation of food wastes is a challenging opportunity for the green, sustainable, and competitive development of industry. The recovery of phenols contributes to the sustainability of olive waste sector, reducing its environmental impact and promoting the development of innovative formulations of interest for pharmaceutical, nutraceutical, and cosmeceutical applications. In this work, olive mill wastewater was treated through a combination of microfiltration (MF), nanofiltration (NF), and reverse osmosis (RO) in a sequential design to produce polyphenol-enriched fractions that have been investigated for their chemical profile using ultra-high-performance liquid chromatography (UHPLC), and their potential antioxidant, hypolipidemic, and hypoglycaemic activities. RO retentate exhibited the highest content of hydroxytyrosol, tyrosol, oleuropein, verbascoside, vanillic acid, and luteolin. In particular, a content of hydroxytyrosol of 1522.2 mg/L, about five times higher than the MF feed, was found. RO retentate was the most active extract in all in vitro tests. Interestingly, this fraction showed a 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic) acid (ABTS) radicals scavenging activity with an IC₅₀ value of 6.9 μg/mL and a potential inhibition of lipid peroxidation evaluated by the β-carotene bleaching test with IC₅₀ values of 25.1 μg/mL after 30 min of incubation. Moreover, RO retentate inhibited α-amylase and α-glucosidase with IC₅₀ values of 65.3 and 66.2 μg/mL, respectively.

Varietal Effect on the Concentration and Anti-Inflammatory Activity of Hydroxytyrosol in French Olive Oils

Numerous studies have been carried out on the bioactive properties of hydroxytyrosol (HT) in olive oils (OOs), although there are few reports comparing anti-inflammatory activity among different olive varieties or regions of production. The purpose of this study was to investigate the in vitro inflammatory action of HT in extracts of four OO varieties in the Languedoc region of the French Mediterranean. Factors other than cultivar were eliminated, which enabled unambiguous varietal differences to be identified. Purified extracts of OO were obtained using an optimized solid-phase extraction procedure by which only polar compounds were recovered. High performance liquid chromatography-photodiode array detection-tandem mass spectrometry was used to identify and quantify HT and oleacein in the extracts. The total polyphenol concentration ranged from 93.00 mg gallic acid equivalent/kg OO for Picholine to 27 mg gallic acid equivalent for Verdale OOs. The concentrations of HT in Picholine, Olivère, and Lucques varieties were 25.3, 18.8 and 12.1 mg/kg, respectively, whereas the concentration of HT in Verdale OOs was less, 1 mg/kg. The in vitro anti-inflammatory response of purified OO extracts, evaluated by the inhibition of nitric oxide release in lipopolysaccharide-induced interferon-γ activated J774.A1 macrophages, strongly correlated with total polyphenol content (R² > 0.995). The effect increased asymptotically between the equivalent of 2 and 37 mg of OO, reaching, at the maximum tested concentration, 90%, 75%, 62%, and 30% activity for Picholine, Olivière, Lucques, and Verdale, respectively. The results presented here clearly show that, by comparison with authentic standards, the activity of HT in OO extracts was enhanced in a concentration-dependent manner, varying from 3-fold at the highest extract concentration to over 6.5-fold at the lowest extract concentration. Therefore, the anti-inflammatory activity of OOs should be rationalized on the basis of whole extracts rather than solely on the concentration of HT or other bioactive compounds in OO.