Ellagic acid a multi-target bioactive compound for drug discovery in CNS? A narrative review

Green and shape-tunable synthesis of ellagic acid crystalline particles by tannic acid for neuroprotection against oxidative stress

Oxidative stress (OS) plays an important role in the emergence and prevention of neurodegenerative diseases, such as Alzheimer's disease (AD). Excess reactive oxygen species (ROS) accumulated in a neuronal cell can lead to OS, producing cell injury and death. Seeking nanoantioxidants against AD-related oxidative stress has attracted a lot of attention, especially those potential antioxidant agents derived from natural polyphenols. However, the transformation of abundant plant polyphenols to antioxidative biomaterials against OS is still challenging. In this work, we report a new method to transform amorphous tannic acid (TA) into tailorable shaped ellagic acid (EA) crystalline particles without using an organic solvent. EA crystalline particles were generated from TA, which underwent a chemical transformation, in situ metal phenolic coordination and acid-induced assembly process, and the size and shape could be controlled by varying the amount of acid. As-prepared EA crystalline particles showed excellent stability in water and lysosomal mimicking fluid and possess unique fluorescence properties and a strong response in mass spectrometry, which is beneficial for their imaging analysis in cells and tissues. More importantly, EA particles have shown significant H2O2-related ROS scavenging ability, a high cellular uptake capacity, an excellent neuroprotective effect in PC12 cells, a high drug loading capacity and BBB permeability to enter the brain. Our study suggested that the EA crystalline particles show great potential for OS-mediated AD treatment.

Effects of Ellagic Acid on Glucose and Lipid Metabolism: A Systematic Review and Meta-Analysis

Background

Abnormal glucose and lipid metabolism (GALM) serve as both a cause and an inducer for the development of the disease. Improvement and treatment of GALM are an important stage to prevent the occurrence and development of the disease. However, current clinical treatment for GALM is limited. Ellagic acid (EA), a common polyphenol present in foods, has been shown to improve abnormalities in GALM observed in patients suffering from metabolic diseases.

Objective

This study used a meta-analysis method to systematically assess the effects of EA on GALM.

Method

As of November 8, 2023, a comprehensive search was conducted across 5 databases, namely, PubMed, Embase, Web of Science, Cochrane Library, and Google Scholar to identify randomized controlled trials (RCTs) in which EA served as the primary intervention for diseases related to GALM. The risk of bias within the included studies was assessed according to the Cochrane Handbook. All statistical analyzes were performed using RevMan 5.4 software.

Results

In this study, a total of 482 articles were retrieved, resulting in the inclusion of 10 RCTs in the meta-analysis. The results showed that EA could reduce fasting blood glucose (FBG) (p = 0.008), increase insulin secretion (p = 0.01), improve insulin resistance index (HOMA-IR) (p = 0.003), decrease triglyceride (TG) (p = 0.004), and reduce cholesterol (Chol) (p = 0.04) and low-density lipoprotein (LDL-c) (p = 0.0004). EA had no significant effect on waist circumference (WC), body weight (BW), body mass index (BMI), 2 hours after prandial blood glucose (2 h-PG), total cholesterol (TC), and high-density lipoprotein (HDL-c).

Conclusions

The effect of improvement in glucose and lipids of EA was closely related to the dose and the intervention time. EA can improve GALM caused by diseases. To corroborate the findings of this study and improve the reliability of the results, EA is imperative to refine the research methodology and increase the sample size in future investigations.

Sono-assembly of ellagic acid into nanostructures significantly enhances aqueous solubility and bioavailability

INTRODUCTION

Ellagic acid (EA), commonly found in foods, offers significant health benefits in combating chronic diseases. However, its therapeutic potential is hindered by its extremely poor solubility and bioavailability.

METHOD

In this study, EA nanoparticles (EA NPs) were produced using a sono-assembly method, without additional agents.

RESULTS

EA NPs exhibited stick-like nanoparticle structures with an average size of 147.3 ± 0.73 nm. EA NPs likely adopt a tunnel-type solvate structure, with 4 water participating in disruption of intramolecular hydrogen bonds in EA and establishment of intermolecular hydrogen bonds between EAs. Importantly, EA NPs exhibited remarkable enhancements in water solubility, with 120.7-fold increase in water, and 97.8-fold increase in pH 6.8 buffer. Moreover, ex vivo intestinal permeability studies demonstrated significant improvements (P < 0.5). These findings were further supported by in vivo pharmacokinetic studies, where EA NPs significantly enhanced the relative bioavailability of EA by 4.69 times.

Phenolic Compounds Profile and Antioxidant Capacity of Plant-Based Protein Supplements

The study aimed to determine the phenolic content and antioxidant capacity of five protein supplements of plant origin. The content and profile of phenolics were determined using the UHPLC-DAD-MS method, while antioxidant capacity (ABTS and DPPH assays) and total phenolic content (TPC) were evaluated using spectrophotometric tests. In the analyzed proteins, twenty-five polyphenols were detected, including eleven phenolic acids, thirteen flavonoids, and one ellagitannin. Hemp protein revealed the highest individual phenolics content and TPC value (1620 μg/g and 1.79 mg GAE/g, respectively). Also, hemp protein showed the highest antioxidant activity determined via ABTS (9.37 μmol TE/g) and DPPH (9.01 μmol TE/g) assays. The contents of p-coumaric acid, m-coumaric acid, kaempferol, rutin, isorhamnetin-3-O-rutinoside, kaempferol-3-O-rutinoside, and TPC value were significantly correlated with antioxidant activity assays. Our findings indicate that plant-based protein supplements are a valuable source of phenols and can also be used in research related to precision medicine, nutrigenetics, and nutrigenomics. This will benefit future health promotion and personalized nutrition in the prevention of chronic diseases.

Valorisation of Raspberry Seeds in Cosmetic Industry-Green Solutions

The fruit processing industry generates large quantities of by-products well known to be rich in bioactive compounds with numerous nutritional properties and beneficial effects for human health. We developed a strategy to valorise raspberry seeds and obtain valuable ingredients with potential application in cosmetic skincare formulas. Cold press extraction technology was applied to extract oil, and the remaining defatted raspberry seed cake was treated with three proline based deep eutectic solvents (DES) to extract polyphenols. The most potent was proline/citric acid extract, with free and total ellagic acid content (52.4 mg/L and 86.4 mg/L), total phenolic content (TPC, 550.1 mg GAE/L) and radical scavenging activity (RSA, 4742.7 mmol TE/L). After the direct mixing of the extract and after encapsulation with starch as a carrier, the skincare emulsion and microemulsion were characterised by irritation potential (Zein test), transepidermal water loss (TEWL), red blood cell (RBC), and DPPH antioxidant test. The resulting preparations were of improved quality in comparison to the control hand cream, with a low skin irritation effect, lower TEWL, and higher antioxidant potential. This work complies with circular economy principles and green technology standards, and represents the efficient model on how to reuse natural resources through waste minimization.

Integrating natural compounds and nanoparticle-based drug delivery systems: A novel strategy for enhanced efficacy and selectivity in cancer therapy

Cancer remains a leading cause of death worldwide, necessitating the development of innovative and more effective treatment strategies. Conventional cancer treatments often suffer from limitations such as systemic toxicity, poor pharmacokinetics, and drug resistance. Recently, there has been growing attention to utilizing natural compounds derived from various sources as possible cancer therapeutics. Natural compounds have demonstrated diverse bioactive properties, including antioxidant, anti-inflammatory, and antitumor effects, making them attractive candidates for cancer treatment. However, their limited solubility and bioavailability present challenges for effective delivery to cancer cells. To overcome these limitations, researchers have turned to nanotechnology-based drug delivery systems. Nanoparticles, with their small size and unique properties, can encapsulate therapeutic agents and offer benefits such as improved solubility, prolonged drug release, enhanced cellular uptake, and targeted delivery. Functionalizing nanoparticles with specific ligands further enhances their precision in recognizing and binding to cancer cells. Combining natural compounds with nanotechnology holds great promise in achieving efficient and safe cancer treatments by enhancing bioavailability, pharmacokinetics, and selectivity toward cancer cells. This review article provides an overview of the advancements in utilizing natural substances and nanotechnology-based drug delivery systems for cancer treatment. It discusses the benefits and drawbacks of various types of nanoparticles, as well as the characteristics of natural compounds that make them appealing for cancer therapy. Additionally, current research on natural substances and nanoparticles in preclinical and clinical settings is highlighted. Finally, the challenges and future perspectives in developing natural compound-nanoparticle-based cancer therapies are discussed.

Protective effects and mechanisms of ellagic acid on intestinal injury in piglets infected with porcine epidemic diarrhea virus

The present study was conducted to decipher the protection effects of ellagic acid (EA) on piglets infected with porcine epidemic diarrhea virus (PEDV). Thirty 7-day-old piglets were randomly assigned to three treatment groups: control, PEDV, and EA + PEDV groups. After a 3-day period of adaption, piglets in the EA + PEDV group were orally administered with 20 mg/kg·BW EA during days 4-11 of the trial. On day 8, piglets were orally administered with PEDV at a dose of 106 TCID50 (50% tissue culture infectious dose) per pig. Additionally, intestinal porcine epithelial (IPEC-1) cells infected with PEDV were used to investigate the anti-PEDV effect of EA in vitro. The results showed that EA at a dose of 10-40 μmol/L increased the viability of PEDV-infected IPEC-1 cells, and EA administration mitigated intestinal edema in piglets challenged with PEDV. Further studies indicated that EA treatment significantly increased the proportion of white blood cells in blood and concentrations of IL-6, IL-1β, and IL-10 in the serum, but decreased the TNF-α content and gene expression of IL-6, IL-1β, TNF-α, and CXCL2 in the jejunum. Moreover, EA intervention considerably elevated the activity of total superoxide dismutase (T-SOD), but decreased the H2O2 concentration in the ileum of piglets. Importantly, EA suppressed the increased expression of antiviral-related genes and proteins (including MXI, ISG15, HSP70, and p-IRF7) induced by PEDV challenge in the jejunum. Furthermore, PEDV infection increased the protein abundance of p-JAK2 and p-STAT3, which were further enhanced by EA supplementation. In conclusion, our results revealed that EA could promote the restoration of intestinal homeostasis by regulating the interferon pathway that was interrelated with the activation of JAK2/STAT3 signaling. These findings provide theoretical basis for the use of EA as a therapy targeting PEDV infection in piglets.

Ellagic Acid Prevents α-Synuclein Spread and Mitigates Toxicity by Enhancing Autophagic Flux in an Animal Model of Parkinson's Disease

Parkinson's disease (PD) is the second most common neurological disorder, pathologically characterized by loss of dopaminergic neurons in the substantia nigra pars compacta (SNc) as well as the formation of Lewy bodies composed mainly of α-synuclein (α-syn) aggregates. It has been documented that abnormal aggregation of α-syn is one of the major causes of developing PD. In the current study, administration of ellagic acid (EA), a polyphenolic compound (10 mg/kg bodyweight), significantly decreased α-syn spreading and preserved dopaminergic neurons in a male C57BL/6 mouse model of PD. Moreover, EA altered the autophagic flux, suggesting the involvement of a restorative mechanism meditated by EA treatment. Our data support that EA could play a major role in the clearing of toxic α-syn from spreading, in addition to the canonical antioxidative role, and thus preventing dopaminergic neuronal death.

Inhibition of the NF-κB and mTOR targets by urolithin A attenuates D-galactose-induced aging in mice

Urolithin A (Uro-A), an intestinal microbiota metabolite of ellagitannin, has anti-aging properties. Through the direct intake of ellagitannin (or ellagic acid) and strains capable of producing Uro-A, the transformation of Uro-A in vivo is a potential method to develop anti-aging preparations. Therefore, this study aimed to investigate the dose-response relationship between the colonic infusion of Uro-A and its anti-aging effects. Results indicated that Uro-A exhibited a dose-dependent anti-aging effect in the colon, and the minimum effective dose might be 3.0 mg kg-1 day-1. The main manifestations were that, compared with the model group, 3.0 mg kg-1 day-1 and 15.0 mg kg-1 day-1 of Uro-A can increase forelimb grip strength by 11.87% and 16.72%, respectively, and increase the discrimination index by 92.14% and 238.11%, respectively. Both doses effectively inhibited the D-galactose-induced increase in oxidative stress levels in the body, muscle atrophy, and neuronal apoptosis. Additionally, Uro-A released through the colon could alleviate D-galactose-induced aging in mice by inhibiting NF-κB and mTOR targets, providing significant protection for motor and cognitive functions. These findings provide a theoretical basis for future application and development of ellagitannin (or ellagic acid) in combination with strains capable of producing Uro-A.

Overexpressed SIRT6 ameliorates doxorubicin-induced cardiotoxicity and potentiates the therapeutic efficacy through metabolic remodeling

Since the utilization of anthracyclines in cancer therapy, severe cardiotoxicity has become a major obstacle. The major challenge in treating cancer patients with anthracyclines is minimizing cardiotoxicity without compromising antitumor efficacy. Herein, histone deacetylase SIRT6 expression was reduced in plasma of patients treated with anthracyclines-based chemotherapy regimens. Furthermore, overexpression of SIRT6 alleviated doxorubicin-induced cytotoxicity in cardiomyocytes, and potentiated cytotoxicity of doxorubicin in multiple cancer cell lines. Moreover, SIRT6 overexpression ameliorated doxorubicin-induced cardiotoxicity and potentiated antitumor efficacy of doxorubicin in mice, suggesting that SIRT6 overexpression could be an adjunctive therapeutic strategy during doxorubicin treatment. Mechanistically, doxorubicin-impaired mitochondria led to decreased mitochondrial respiration and ATP production. And SIRT6 enhanced mitochondrial biogenesis and mitophagy by deacetylating and inhibiting Sgk1. Thus, SIRT6 overexpression coordinated metabolic remodeling from glycolysis to mitochondrial respiration during doxorubicin treatment, which was more conducive to cardiomyocyte metabolism, thus protecting cardiomyocytes but not cancer cells against doxorubicin-induced energy deficiency. In addition, ellagic acid, a natural compound that activates SIRT6, alleviated doxorubicin-induced cardiotoxicity and enhanced doxorubicin-mediated tumor regression in tumor-bearing mice. These findings provide a preclinical rationale for preventing cardiotoxicity by activating SIRT6 in cancer patients undergoing chemotherapy, but also advancing the understanding of the crucial role of SIRT6 in mitochondrial homeostasis.

Pomegranate Fruit Cracking during Maturation: From Waste to Valuable Fruits

The pomegranate is an emerging functional food which is nowadays becoming more and more commercially attractive. Each part of this fruit (peels, arils and seeds) has a specific phytocomplex, rich in anti-oxidant and anti-radical compounds. Among these, punicalagin and ellagic acid continue to be widely studied for their numerous beneficial effects on human health (anti-inflammatory effects, anti-diabetes activity, cardio-protection, cancer prevention). Despite their exceptionally valuable composition and high adaptability to different climatic conditions, pomegranate fruits are highly susceptible to splitting during different stages of ripening, so much so that an estimated 65% of the production may be lost. A "zero-kilometer" approach should therefore be adopted to utilize such a valuable product otherwise destined to be downgraded or even incinerated, with a very high environmental impact. The aim of this work is to highlight and compare the compositional differences between whole and split pomegranates belonging to the cultivar Dente di Cavallo, grown in Apulia (Italy), to assess a valuable role for this split fruit usually considered as waste. The arils and peels are subjected to extraction procedures and the extracts analyzed by CIEL*a*b*, HPLC-DAD and HS-SPME/GC-MS. Moreover, an assessment of the inhibitory activity against α-glucosidase, acetylcholinesterase and tyrosinase enzymes has also been applied. The data show a better chemical profile in split fruits (namely 60% more anthocyanin content than intact fruit) with very interesting results in terms of α-glucosidase inhibition. The juices obtained by squeezing are also compared to commercial juices ("Salus Melagrana" and "La Marianna") processed from the same cultivar and subjected to the same protocol analysis.

Rational design and evaluation of 2-((pyrrol-2-yl)methylene)thiophen-4-ones as RNase L inhibitors

Ribonuclease L (RNase L) plays a crucial role in an antiviral pathway of interferon-induced innate immunity by degrading RNAs to prevent viral replication. Modulating RNase L activity thus mediates the innate immune responses and inflammation. Although a few small molecule-based RNase L modulators have been reported, only limited molecules have been mechanistically investigated. This study explored the strategy of RNase L targeting by using a structure-based rational design approach and evaluated the RNase L-binding and inhibitory activities of the yielded 2-((pyrrol-2-yl)methylene)thiophen-4-ones, which exhibited improved inhibitory effect as determined by in vitro FRET and gel-based RNA cleavage assay. A further structural optimization study yielded selected thiophenones that showed >30-fold more potent inhibitory activity than that of sunitinib, the approved kinase inhibitor with reported RNase L inhibitory activity. The binding mode with RNase L for the resulting thiophenones was analyzed by using docking analysis. Furthermore, the obtained 2-((pyrrol-2-yl)methylene)thiophen-4-ones exhibited efficient inhibition of RNA degradation in cellular rRNA cleavage assay. The newly designed thiophenones are the most potent synthetic RNase L inhibitors reported to date and the results revealed in our study lay the foundation for the development of future RNase L-modulating small molecules with new scaffold and improved potency.

Unravelling the destabilization potential of ellagic acid on α-synuclein fibrils using molecular dynamics simulations

The aberrant deposition of α-synuclein (α-Syn) protein into the intracellular neuronal aggregates termed Lewy bodies and Lewy neurites characterizes the devastating neurodegenerative condition known as Parkinson's disease (PD). The disruption of pre-existing disease-relevant α-Syn fibrils is recognized as a viable therapeutic approach for PD. Ellagic acid (EA), a natural polyphenolic compound, is experimentally proven as a potential candidate that prevents or reverses the α-Syn fibrillization process. However, the detailed inhibitory mechanism of EA against the destabilization of α-Syn fibril remains largely unclear. In this work, the influence of EA on α-Syn fibril and its putative binding mechanism were explored using molecular dynamics (MD) simulations. EA interacted primarily with the non-amyloid-β component (NAC) of α-Syn fibril, disrupting its β-sheet content and thereby increasing the coil content. The E46-K80 salt bridge, critical for the stability of Greek-key-like α-Syn fibril, was disrupted in the presence of EA. The binding free energy analysis using the MM-PBSA method demonstrates the favourable binding of EA to α-Syn fibril (ΔG_binding = -34.62 ± 11.33 kcal mol^-1). Interestingly, the binding affinity between chains H and J of the α-Syn fibril was significantly reduced on the incorporation of EA, which highlights the disruptive ability of EA towards α-Syn fibril. The MD simulations provide mechanistic insights into the α-Syn fibril disruption by EA, which gives a valuable direction for the development of potential inhibitors of α-Syn fibrillization and its associated cytotoxicity.

In Silico and In Vitro Study of Antioxidant Potential of Urolithins

In this work, quantum chemical calculations based on density functional theory (DFT) were performed to predict the antioxidant potential of four bioactive gut microbiota metabolites of the natural polyphenols ellagitannins (ETs) and ellagic acid (EA), also known as urolithins (UROs). In order to evaluate their ability to counter the effect of oxidative stress caused by reactive oxygen species (ROS), such as the hydroperoxyl radical (•OOH), different reaction mechanisms were investigated, considering water and lipid-like environments. Through our in silico results, it emerged that at physiological pH, the scavenging activity of all urolithins, except urolithin B, are higher than that of trolox and other potent antioxidants existing in nature, such as EA, α-mangostin, allicin, caffeine and melatonin. These findings were confirmed by experimental assays.

An integrated targeted metabolomics and network pharmacology approach to exploring the mechanism of ellagic acid against sleep deprivation-induced memory impairment and anxiety

Background

As a neuroprotective agent, ellagic acid (EA) is extremely beneficial. Our previous study found that EA can alleviate sleep deprivation (SD)-induced abnormal behaviors, although the mechanisms underlying this protective effect have not yet been fully elucidated.

Objective

An integrated network pharmacology and targeted metabolomics approach was utilized in this study to investigate the mechanism of EA against SD-induced memory impairment and anxiety.

Methods

Behavioral tests were conducted on mice after 72 h of SD. Hematoxylin and eosin staining and nissl staining were then carried out. Integration of network pharmacology and targeted metabolomics was performed. Eventually, the putative targets were further verified using molecular docking analyses and immunoblotting assays.

Results

The present study findings confirmed that EA ameliorated the behavioral abnormalities induced by SD and prevented histopathological and morphological damage to hippocampal neurons. Through multivariate analysis, clear clustering was obtained among different groups, and potential biomarkers were identified. Four key targets, catechol-O-methyltransferase (COMT), cytochrome P450 1B1 (CYP1B1), glutathione S-transferase A2 (GSTA2), and glutathione S-transferase P1 (GSTP1), as well as the related potential metabolites and metabolic pathways, were determined by further integrated analysis. Meanwhile, in-silico studies revealed that EA is well located inside the binding site of CYP1B1 and COMT. The experimental results further demonstrated that EA significantly reduced the increased expression of CYP1B1 and COMT caused by SD.

Conclusion

The findings of this study extended our understanding of the underlying mechanisms by which EA treats SD-induced memory impairment and anxiety, and suggested a novel approach to address the increased health risks associated with sleep loss.

UHPLC-Triple-TOF-MS Characterization, Antioxidant, Antimicrobial and Antiproliferative Activity of Raspberry (Rubus idaeus L.) Seed Extracts

The primary aim of this experiment was to investigate the bioactivity potential and polyphenolic profile of defatted raspberry seeds (DRS) extracts from three varieties (Willamette, Meeker, and Polka) using the in vitro tests HPLC-DAD and UHPLC-Triple-TOF-MS. Extracts were obtained using ultrasound-assisted extraction (UAE) or hydrolysis. The antioxidant activity of the extracts was tested using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic) cation (ABTS), and ferric reducing antioxidant power (FRAP) assays. Furthermore, the extracts were tested for antimicrobial activity using the disk diffusion method for four bacterial cultures (Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, and Salmonella enterica subsp. enterica Enteritidis). In vitro antiproliferative activity was tested using cervical carcinoma (HeLa), breast adenocarcinoma (MCF7), and fetal lung (MRC-5) human cell lines. In total, 32 phenolic compounds were detected in DRS extracts. A small quantity of ellagic acid (EA) was in free form, while EA content increased after the hydrolysis process. The extracts from the Meeker variety exhibited the highest antioxidant activity, analyzed with DPPH and FRAP assays, while extracts from the Polka variety had the highest activity towards ABTS•⁺ radical scavenging activity. The UAE samples expressed higher antiproliferative activity in comparison to hydrolysis extracts. The results indicate that DRS extracts have certain bioactivity, and their use in the food, cosmetic, and pharmaceutical industries is recommended.

Potential implications of polyphenolic compounds in neurodegenerative diseases

Neurodegenerative diseases are common chronic diseases related to progressive damage to the nervous system. Current neurodegenerative diseases present difficulties and despite extensive research efforts to develop new disease-modifying therapies, there is still no effective treatment for halting the neurodegenerative process. Polyphenols are biologically active organic compounds abundantly found in various plants. It has been reported that plant-derived dietary polyphenols may improve some disease states and promote health. Emerging pieces of evidence indicate that polyphenols are associated with neurodegenerative diseases. This review aims to overview the potential neuroprotective roles of polyphenols in most common neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease, epilepsy, and ischemic stroke.

Ellagic acid: insight into its protective effects in age-associated disorders

The disparity in the free radical generation and the production of antioxidants to counteract its effect is known as oxidative stress. Oxidative stress causes damage to the macromolecules such as lipids, carbohydrates, proteins, and DNA and RNA. The oxidative damage to the cellular components leads to a process of aging and various age-associated disorders. The literature survey for this review was done using PubMed, Google Scholar, and Science Direct. The papers showing the studies related to aging and age-associated disorders have been selected for reviewing this paper. Ellagic acid has been used as the keyword, and more emphasis has been put on papers from the last 10 years. However, some papers with significant studies prior to 10 years have also been considered. Almost 250 papers have been studied for reviewing this paper, and about 135 papers have been cited. Ellagic acid (EA) is present in high quantities in pomegranate and various types of berries. It is known to possess the antioxidant potential and protects from the harmful effects of free radicals. Various studies have shown its effect to protect cardiovascular, neurodegenerative, cancer, and diabetes. The present review focuses on the protective effect of ellagic acid in age-associated disorders. The effect of EA has been studied in various chronic disorders but the scope of this review is limited to cancer, diabetes, cardiovascular and neurodegenerative disorders. All the disease aspects have not been addressed in this particular review.

Pharmacotherapeutic potential of pomegranate in age-related neurological disorders

Age-related neurological disorders [AND] include neurodegenerative diseases [NDDs] such as Alzheimer's disease [AD] and Parkinson's disease [PD], which are the most prevalent types of dementia in the elderly. It also includes other illnesses such as migraine and epilepsy. ANDs are multifactorial, but aging is their major risk factor. The most frequent and vital pathological features of AND are oxidative stress, inflammation, and accumulation of misfolded proteins. As AND brain damage is a significant public health burden and its incidence is increasing, much has been done to overcome it. Pomegranate (Punica granatum L.) is one of the polyphenol-rich fruits that is widely mentioned in medical folklore. Pomegranate is commonly used to treat common disorders such as diarrhea, abdominal pain, wound healing, bleeding, dysentery, acidosis, microbial infections, infectious and noninfectious respiratory diseases, and neurological disorders. In the current review article, we aimed to summarize the data on the pharmacotherapeutic potentials of pomegranate in ANDs.

Insights into the Explicit Protective Activity of Herbals in Management of Neurodegenerative and Cerebrovascular Disorders

The longstanding progressive neurodegenerative conditions of the central nervous system arise mainly due to deterioration, degradation and eventual neuronal cell loss. As an individual ages, the irreversible neurodegenerative disorders associated with aging also begin to develop, and these have become exceedingly prominent and pose a significant burden mentally, socially and economically on both the individual and their family. These disorders express several symptoms, such as tremors, dystonia, loss of cognitive functions, impairment of motor activity leading to immobility, loss of memory and many more which worsen with time. The treatment employed in management of these debilitating neurodegenerative disorders, such as Parkinson’s disease (which mainly involves the loss of dopaminergic neurons in the nigrostriatal region), Alzheimer’s disease (which arises due to accumulation of Tau proteins causing diffusive atrophy in the brain), Huntington’s disease (which involves damage of striatal and spinal neurons, etc.), have several adverse effects, leading to exploration of several lead targets and molecules existing in herbal drugs. The current review highlights the mechanistic role of natural products in the treatment of several neurodegenerative and cerebrovascular diseases such as Parkinson’s disease, Alzheimer’s disease, ischemic stroke and depression.

Ellagic Acid: A Dietary-Derived Phenolic Compound for Drug Discovery in Mild Cognitive Impairment

Ellagic acid (EA), a naturally occurring polyphenolic compound, is detected in free form or linked to polyols or sugars, constituting hydrolyzable tannins or ellagitannins in distinct fruits, nuts, and herbs. Today, a considerable number of botanicals and enriched foods containing EA are commercially available as nutraceuticals and used to prevent mild cognitive impairment (MCI) due to the excellent neuroprotective capacity of EA. Here, this study aims to provide an overview of the physicochemical properties, source, and pharmacokinetics of EA and to emphasize the importance and mechanisms of EA in the prevention and management of MCI. To date, preclinical studies of EA and its derivatives in various cell lines and animal models have advanced the idea of dietary EA as a feasible agent capable of specifically targeting and improving MCI. The molecular mechanisms of EA and its derivatives to prevent or reduce MCI are mainly through reducing neuroinflammation, oxidative stress, neuronal apoptosis, synaptic dysfunction and loss, and defective mitochondrial functions. Nevertheless, well-designed and correctly large randomized controlled trials in the human population need to be performed to reinforce the scientific facticity of the beneficial effects of EA against MCI. Synchronously, the mechanism of EA against MCI is least provided cynosure and expects more attention from the emerging research community.

Ethyl Acetate Fraction of Bixa orellana and Its Component Ellagic Acid Exert Antibacterial and Anti-Inflammatory Properties against Mycobacterium abscessus subsp. massiliense

Mycobacterium abscessus subsp. massiliense (Mabs) causes chronic infections, which has led to the need for new antimycobacterial agents. In this study, we investigated the antimycobacterial and anti-inflammatory activities of the ethyl acetate fraction of Bixa orellana leaves (BoEA) and ellagic acid (ElAc). In silico analysis predicted that ElAc had low toxicity, was not mutagenic or carcinogenic, and had antimicrobial and anti-inflammatory activities. Apparently, ElAc can interact with COX2 and Dihydrofolate reductase (DHFR) enzymes, which could explain both activities. In vitro analysis showed that BoEA and ElAc exerted antimicrobial activity against Mabs (minimum inhibitory concentration of 1.56, 1.56 mg/mL and bactericidal concentration of 6.25, 3.12 mg/mL, respectively. Clarithromycin showed MIC and MBC of 1 and 6 µg/mL). Treatment with BoEA or ElAc increased survival of Tenebrio molitor larvae after lethal infection with Mabs and reduced carrageenan-induced paw edema in mice, around 40% of edema volume after the fourth hour, similarly to diclofenac. In conclusion, BoEA and ElAc exert antimicrobial effects against Mabs and have anti-inflammatory effects, making them potential sources of antimycobacterial drugs. The biological activities of ElAc may be due to its high binding affinities predicted for COX2 and DHFR enzymes.

Synergism of ellagic acid in combination with radiotherapy and chemotherapy for cancer treatment

BACKGROUND

Ellagic acid (EA) is a polyphenol compound abundant in berries, walnuts, pecans, pomegranate, cranberries, and other plant foods and exerts a wide array of biological properties. In particular, EA has received considerable research attention in anti-cancer therapy. EA administered alone has been shown to exert effects against human cancers through multiple pathways. In addition, EA may increase tumor sensitivity to chemotherapy and radiotherapy. Namely, EA combination with a relatively low dosage of therapeutic drugs or optimized radiation dose could improve the treatment outcome. More importantly, EA could counteract chemotherapy-related adverse reactions.

PURPOSE

This review aims to summarize the in vitro and in vivo experimental evidence of synergism of EA in radiotherapy/chemotherapy for the treatment of cancers. In addition, the preventive effect of EA to counteract chemotherapy-induced toxicity is also discussed.

METHODS

The searches were performed in the PubMed, Web of Science and Google scholar and introduced the information about the role of EA in cancer treatment.

RESULTS

EA exhibits synergistic effects in radiotherapy/chemotherapy for the treatment of cancers and exerts a great potential in reducing the side effects of chemotherapy and radiotherapy due to its biological activities, such as antioxidant and anti-inflammatory activities.

CONCLUSION

EA could be a promising drug adjuvant for cancer treatment. In the near future, novel strategies for EA delivery systems that overcome the low EA solubility and bioavailability should be studied further to fully exploit the therapeutic potential of EA.

Ellagic Acid: A Review on Its Natural Sources, Chemical Stability, and Therapeutic Potential

Ellagic acid (EA) is a bioactive polyphenolic compound naturally occurring as secondary metabolite in many plant taxa. EA content is considerable in pomegranate (Punica granatum L.) and in wood and bark of some tree species. Structurally, EA is a dilactone of hexahydroxydiphenic acid (HHDP), a dimeric gallic acid derivative, produced mainly by hydrolysis of ellagitannins, a widely distributed group of secondary metabolites. EA is attracting attention due to its antioxidant, anti-inflammatory, antimutagenic, and antiproliferative properties. EA displayed pharmacological effects in various in vitro and in vivo model systems. Furthermore, EA has also been well documented for its antiallergic, antiatherosclerotic, cardioprotective, hepatoprotective, nephroprotective, and neuroprotective properties. This review reports on the health-promoting effects of EA, along with possible mechanisms of its action in maintaining the health status, by summarizing the literature related to the therapeutic potential of this polyphenolic in the treatment of several human diseases.

Healthy Properties of a New Formulation of Pomegranate-Peel Extract in Mice Suffering from Experimental Autoimmune Encephalomyelitis

A new formulation of a pomegranate-peel extract (PEm) obtained by PUAE (Pulsed Ultrasound-Assisted Extraction) and titrated in both ellagic acid (EA) and punicalagin is proposed, characterized and then analyzed for potential health properties in mice suffering from the experimental autoimmune encephalomyelitis (EAE). PEm effects were compared to those elicited by a formulation containing EA (EAm). Control and EAE mice were chronically administered EAm and Pem dissolved in the drinking water, starting from the day 10 post-immunization (d.p.i.), with a “therapeutic” protocol to deliver daily 50 mg/kg of EA. Treated EAE mice did not limit their daily access to the beverage, nor did they show changes in body weight, but they displayed a significant amelioration of “in vivo” clinical symptoms. “Ex vivo” histochemical analysis showed that spinal-cord demyelination and inflammation in PEm and EAm-treated EAE mice at 23 ± 1 d.p.i. were comparable to those in the untreated EAE animals, while microglia activation (measured as Ionized Calcium Binding Adaptor 1, Iba1 staining) and astrocytosis (quantified as glial fibrillar acid protein, GFAP immunopositivity) significantly recovered, particularly in the gray matter. EAm and PEm displayed comparable efficiencies in controlling the spinal pathological cellular hallmarks in EAE mice, and this would support their delivery as dietary supplementation in patients suffering from multiple sclerosis (MS).

Simultaneous Hydrolysis of Ellagitannins and Extraction of Ellagic Acid from Defatted Raspberry Seeds Using Natural Deep Eutectic Solvents (NADES)

Defatted raspberry seeds were used as an alternative source of antioxidants and ellagic acid (EA) extracted using Natural deep eutectic solvents (NADES). In the preliminary study, the best NADES combination (citric acid-betaine) and the most influential variables (temperature, time, and NADES/plant ratio) were selected for the further optimization process. All samples were analyzed in terms of total polyphenol, EA content, and antioxidant activity. Two sets of optimal conditions were generated by response surface methodology. The first set (Opt1) was designed for higher conversion of ellagitannins to EA while the latter set (Opt2) for higher EA content/100 g extract. Opt1 and Opt2 had higher values for all investigated responses compared to 80% ethanolic extract but had a lower conversion rate of ellagitannins to EA compared to acidified methanol extract. The third set of parameters (Opt3) selected beyond the initial experimental domain was used to obtain a sample with the highest EA content/100 g extract. Due to their nature, NADES extracts are ready to use and could have various technological roles in products since they are antioxidants, acidifiers, and colorants. NADES raspberry extracts exhibited higher anti-proliferative activity compared to ethanolic extracts in terms of EC50 values. However, the main contributor of anti-cancer activity in NADES raspberry extracts were individual NADES compounds and/or their newly formed NADES structure.

Ellagic Acid Alleviates Oxidative Stress by Mediating Nrf2 Signaling Pathways and Protects against Paraquat-Induced Intestinal Injury in Piglets

The gastrointestinal tract is a key source of superoxide so as to be one of the most vulnerable to oxidative stress damage. Ellagic acid (EA), a polyphenol displays widely biological activities owing to its strong antioxidant properties. Here, we investigated the protective benefits of EA on oxidative stress and intestinal barrier injury in paraquet (PQ)-challenged piglets. A total of 40 weaned piglets were randomly divided into five groups: Control, PQ, 0.005% EA-PQ, 0.01% EA-PQ, and 0.02% EA-PQ. Piglets were intraperitoneally injected with 4 mg/kg (BW) PQ or saline on d-18, and sacrificed on d-21 of experiment. EA treatments eliminated growth-check induced by PQ and increased serum superoxide dismutase (SOD) activity but decreased serum malondialdehyde (MDA) level as compared to PQ group. EA supplementation promoted Nrf2 nuclear translocation and enhanced heme oxygenase-1 (HO-1) and quinone oxidoreductase 1 (NQO1) protein abundances of small intestinal mucosa. Additionally, EA improved PQ-induced crypt deepening, goblet cells loss, and villi morphological damage. Consistently, EA increased tight junction protein expression as was evident from the decreased serum diamine oxidase (DAO) levels. EA could ameliorate the PQ-induced oxidative stress and intestinal damage through mediating Nrf2 signaling pathway. Intake of EA-rich food might prevent oxidative stress-mediated gut diseases.

Ellagic Acid Modulates the Amyloid Precursor Protein Gene via Superoxide Dismutase Regulation in the Entorhinal Cortex in an Experimental Alzheimer's Model

Patients suffering from Alzheimer's disease (AD) are still increasing worldwide. The development of (AD) is related to oxidative stress and genetic factors. This study investigated the therapeutic effects of ellagic acid (EA) on the entorhinal cortex (ERC), which plays a major role in episodic memory, in the brains of an AD rat model. AD was induced using AlCl3 (50 mg/kg orally for 4 weeks). Rats were divided into four groups: control, AD model, EA (treated with 50 mg/kg EA orally for 4 weeks), and ADEA (AD rats treated with EA after AlCl3 was stopped) groups. All rats were investigated for episodic memory using the novel object recognition test (NORT), antioxidant serum biomarkers, lipid peroxidation, histopathology of the ERC, and quantitative PCR for the superoxide dismutase (SOD) gene. EA therapy in AD rats significantly increased the discrimination index for NORT and the levels of SOD, glutathione, and total antioxidant capacity. Lipid peroxidation products were decreased, and the neurofibrillary tangles and neuritic plaques in the ERC sections were reduced after EA administration. The decrease in ERC thickness in the AD group, caused by caspase-3-mediated apoptosis and neurotoxicity due to amyloid precursor protein, was modulated by the increased SOD mRNA expression. Adjustment of the ERC antioxidant environment and decreased oxidative stress under EA administration enhanced SOD expression, resulting in the modulation of amyloid precursor protein toxicity and caspase-3-mediated apoptosis, thereby restoring episodic memory.

Presynaptic Release-Regulating Alpha2 Autoreceptors: Potential Molecular Target for Ellagic Acid Nutraceutical Properties

Polyphenol ellagic acid (EA) possesses antioxidant, anti-inflammatory, anti-carcinogenic, anti-diabetic and cardio protection activities, making it an interesting multi-targeting profile. EA also controls the central nervous system (CNS), since it was proven to reduce the immobility time of mice in both the forced swimming and the tail-suspension tests, with an efficiency comparable to that of classic antidepressants. Interestingly, the anti-depressant-like effect was almost nulled by the concomitant administration of selective antagonists of the noradrenergic receptors, suggesting the involvement of these cellular targets in the central effects elicited by EA and its derivatives. By in silico and in vitro studies, we discuss how EA engages with human α_2A-ARs and α_2C-AR catalytic pockets, comparing EA behaviour with that of known agonists and antagonists. Structurally, the hydrophobic residues surrounding the α_2A-AR pocket confer specificity on the intermolecular interactions and hence lead to favourable binding of EA in the α_2A-AR, with respect to α_2C-AR. Moreover, EA seems to better accommodate within α_2A-ARs into the TM5 area, close to S200 and S204, which play a crucial role for activation of aminergic GPCRs such as the α₂-AR, highlighting its promising role as a partial agonist. Consistently, EA mimics clonidine in inhibiting noradrenaline exocytosis from hippocampal nerve endings in a yohimbine-sensitive fashion that confirms the engagement of naïve α₂-ARs in the EA-mediated effect.

NPCDR: natural product-based drug combination and its disease-specific molecular regulation

Natural product (NP) has a long history in promoting modern drug discovery, which has derived or inspired a large number of currently prescribed drugs. Recently, the NPs have emerged as the ideal candidates to combine with other therapeutic strategies to deal with the persistent challenge of conventional therapy, and the molecular regulation mechanism underlying these combinations is crucial for the related communities. Thus, it is urgently demanded to comprehensively provide the disease-specific molecular regulation data for various NP-based drug combinations. However, no database has been developed yet to describe such valuable information. In this study, a newly developed database entitled ‘Natural Product-based Drug Combination and Its Disease-specific Molecular Regulation (NPCDR)’ was thus introduced. This database was unique in (a) providing the comprehensive information of NP-based drug combinations & describing their clinically or experimentally validated therapeutic effect, (b) giving the disease-specific molecular regulation data for a number of NP-based drug combinations, (c) fully referencing all NPs, drugs, regulated molecules/pathways by cross-linking them to the available databases describing their biological or pharmaceutical characteristics. Therefore, NPCDR is expected to have great implications for the future practice of network pharmacology, medical biochemistry, drug design, and medicinal chemistry. This database is now freely accessible without any login requirement at both official (https://idrblab.org/npcdr/) and mirror (http://npcdr.idrblab.net/) sites.

Contribution of Biotransformations Carried Out by the Microbiota, Drug-Metabolizing Enzymes, and Transport Proteins to the Biological Activities of Phytochemicals Found in the Diet

The consumption of dietary phytochemicals has been associated with several health benefits and relevant biological activities. It is postulated that biotransformations of these compounds regulated by the microbiota, Phase I/II reactions, transport proteins, and deconjugating enzymes contribute not only to their metabolic clearance but also, in some cases, to their bioactivation. A number of factors (age, genetics, sex, physiopathological conditions, and the interplay with other dietary phytochemicals) modulating metabolic activities are important sources and contributors to the interindividual variability observed in clinical studies evaluating the biological activities of phytochemicals. In this review, we discuss all the processes that can affect the bioaccessibility and beneficial effects of these bioactive compounds. Herein, we argue that the role of these factors must be further studied to correctly understand and predict the effects observed following the intake of phytochemicals. This is, in particular, with regard to in vitro investigations, which have shown great inconsistency with preclinical and clinical studies. The complexity of in vivo metabolic activity and biotransformation should therefore be considered in the interpretation of results in vitro and their translation to human physiopathology.

Effect of Ellagic Acid on Seizure Threshold in Two Acute Seizure Tests in Mice

Ellagic acid (EA) is a natural dietary polyphenol that has many beneficial properties, including anti-inflammatory, antioxidant, antiviral, antibacterial, and neuroprotective effects. Studies have revealed that EA may modulate seizure activity in chemically induced animal models of seizures. Therefore, the aim of the present study was to investigate the effect of EA on the seizure threshold in two acute seizure tests in male mice, i.e., in the intravenous (i.v.) pentylenetetrazole (PTZ) seizure test and in the maximal electroshock seizure threshold (MEST) test. The obtained results showed that EA (100 mg/kg) significantly elevated the threshold for both the first myoclonic twitch and generalized clonic seizure in the i.v. PTZ seizure test. At the highest dose tested (200 mg/kg), EA increased the threshold for tonic hindlimb extension in the MEST test. EA did not produce any significant changes in motor coordination (assessed in the chimney test) or muscular strength (investigated in the grip-strength test). The plasma and total brain concentration-time profiles of EA after intraperitoneal and oral administration were also determined. Although further studies are necessary to confirm the anticonvulsant activity of EA, our findings suggest that it may modulate seizure susceptibility in animal models.

Neuroprotective Potential of Ellagic Acid: A Critical Review

Ellagic acid (EA) is a dietary polyphenol present in various fruits, vegetables, herbs, and nuts. It exists either independently or as part of complex structures, such as ellagitannins, which release EA and several other metabolites including urolithins following absorption. During the past few decades, EA has drawn considerable attention because of its vast range of biological activities as well as its numerous molecular targets. Several studies have reported that the oxidative stress-lowering potential of EA accounts for its broad-spectrum pharmacological attributes. At the biochemical level, several mechanisms have also been associated with its therapeutic action, including its efficacy in normalizing lipid metabolism and lipidemic profile, regulating proinflammatory mediators, such as IL-6, IL-1β, and TNF-α, upregulating nuclear factor erythroid 2-related factor 2 and inhibiting NF-κB action. EA exerts appreciable neuroprotective activity by its free radical-scavenging action, iron chelation, initiation of several cell signaling pathways, and alleviation of mitochondrial dysfunction. Numerous in vivo studies have also explored the neuroprotective attribute of EA against various neurotoxins in animal models. Despite the increasing number of publications with experimental evidence, a critical analysis of available literature to understand the full neuroprotective potential of EA has not been performed. The present review provides up-to-date, comprehensive, and critical information regarding the natural sources of EA, its bioavailability, metabolism, neuroprotective activities, and underlying mechanisms of action in order to encourage further studies to define the clinical usefulness of EA for the management of neurological disorders.

Strawberry agro-industrial by-products as a source of bioactive compounds: effect of cultivar on the phenolic profile and the antioxidant capacity

The post-harvest processing of strawberries generates considerable amounts of by-products that consist of the inedible parts of the fruit (sepal, calyx, stem, and non-marketable portion of the fruit), which is an environmental problem for local producers and industries. This study aimed to revalue these kinds of tissues through identifying and quantifying the genotype influence on the total phenolic content, phenolic profile, and the antioxidant activity of the by-products from three strawberry cultivars: 'Festival' (FE), 'San Andreas ' (SA), and 'Camino Real' (CR). The total phenolic content was determined by the Folin-Ciocalteu method, in-vitro antioxidant activity by the DPPH* radical scavenging method and the phenolic profile by PAD-HPLC. The different genotypes showed significant differences (p < 0.05) in total phenolic content (TPC), FE being the one with the highest TPC (14.97 g of gallic acid equivalents < GAE > /Kg of by-product < R >), followed by SA and CR cultivars. The antioxidant capacity of the SA and FE tissues were similar (p > 0.05) and higher (15.1-16.3 mmol Trolox equivalents < TE > /Kg R) than CR. Eight main phenolic compounds were identified and quantified on the three cultivars. Agrimoniin was the principal polyphenol (0.38-1.56 g/Kg R), and the cultivar FE had the highest concentration. This compound showed the highest correlation coefficient with the antioxidant capacity (R2 0.87; p < 0.001). This study highlighted the impact of the multi-cultivar systems in strawberry production on the bioactive potential and the diversity of secondary metabolites obtained from strawberry agro-industrial by-products at a low cost.

Role of Polyphenols as Antioxidant Supplementation in Ischemic Stroke

Stroke is the second most common cause of death globally and the leading cause of death in China. The pathogenesis of cerebral ischemia injury is complex, and oxidative stress plays an important role in the fundamental pathologic progression of cerebral damage in ischemic stroke. Previous studies have preliminarily confirmed that oxidative stress should be a potential therapeutic target and antioxidant as a treatment strategy for ischemic stroke. Emerging experimental studies have demonstrated that polyphenols exert the antioxidant potential to play the neuroprotection role after ischemic stroke. This comprehensive review summarizes antioxidant effects of some polyphenols, which have the most inhibition effects on reactive oxygen species generation and oxidative stress after ischemic stroke.

Ellagic acid and urolithin A modulate the immune response in LPS-stimulated U937 monocytic cells and THP-1 differentiated macrophages

Dietary polyphenols are subjected, following ingestion, to an extensive metabolism, and the molecules that act at the cellular and tissue level will be, most likely, metabolites rather than native polyphenols. The mechanisms behind the positive effects exerted by polyphenols are not yet completely elucidated, since most in vitro studies use unmetabolised polyphenols rather than the metabolites present in the body. The aim of this study was to investigate and compare the potential effect of phenolic metabolites on the immune response using U937 monocyte and THP-1 macrophage cell cultures. Of the 16 metabolites tested, urolithins (Uro), and Uro A, in particular were the most potent, showing a modest increase in basal NF-κB activity and a reduction in lipopolysaccaride (LPS)-induced NF-κB activity, gene expression and secretion of pro-inflammatory cytokines. Protocatechuic acid and its sulfate/glucuronide metabolites reduced LPS-induced NF-κB activity, but not IL-6 and TNF-α cytokine secretion. Interestingly, both ellagic acid and its metabolite Uro A had immunomodulating effects, although they regulated the immune response differently, and both reduced LPS-induced NF-κB activity in U937 cells. However, while Uro A dramatically reduced IL-6 and IL-10 mRNA expression, no effect could be observed with ellagic acid. In THP-1 cells, treatment with ellagic acid dramatically reduced the expression of Toll-like receptor 4, while Uro A had no effect. The dual role observed for Uro A, showing both a modest increase in basal NF-κB activity and a reduction in LPS-induced NF-κB activity, as well as a reduction in LPS-induced pro-inflammatory cytokine secretion, makes this metabolite particularly interesting for further studies in animals and humans.

Neuroprotective Effect for Cerebral Ischemia by Natural Products: A Review

Natural products have a significant role in the prevention of disease and boosting of health in humans and animals. Stroke is a disease with high prevalence and incidence, the pathogenesis is a complex cascade reaction. In recent years, it’s reported that a vast number of natural products have demonstrated beneficial effects on stroke worldwide. Natural products have been discovered to modulate activities with multiple targets and signaling pathways to exert neuroprotection via direct or indirect effects on enzymes, such as kinases, regulatory receptors, and proteins. This review provides a comprehensive summary of the established pharmacological effects and multiple target mechanisms of natural products for cerebral ischemic injury in vitro and in vivo preclinical models, and their potential neuro-therapeutic applications. In addition, the biological activity of natural products is closely related to their structure, and the structure-activity relationship of most natural products in neuroprotection is lacking, which should be further explored in future. Overall, we stress on natural products for their role in neuroprotection, and this wide band of pharmacological or biological activities has made them suitable candidates for the treatment of stroke.

Ellagic Acid-Cyclodextrin Complexes for the Treatment of Oral Candidiasis

The increase in the prevalence of fungal infections worldwide and the rise in the occurrence of antifungal resistance suggest that new research to discover antifungal molecules is needed. The aim of this study was to evaluate the potential use of ellagic acid-cyclodextrin complexes (EA/HP-β-CD) for the treatment of oral candidiasis. First, the effect of EA/HP-β-CD on C. albicans planktonic cells and biofilms was evaluated. Then, the cytotoxicity of the effective concentration was studied to ensure safety of in vivo testing. Finally, the in vivo effectiveness was determined by using a murine model of induced oral candidiasis. Data was statistically analyzed. The minimal inhibitory concentration of EA/HP-β-CD was 25 µg/mL and a concentration of 10 times MIC (250 µg/mL) showed an inhibitory effect on C. albicans 48 h-biofilms. The complex at concentration 250 µg/mL was classified as slightly cytotoxic. In vivo experiments showed a reduction in fungal epithelial invasion after treatment with EA/HP-β-CD for 24 h and 96 h when compared to the negative control. In conclusion, the results demonstrated that EA/HP-β-CD has antifungal and anti-inflammatory effects, reducing the invasive capacity of C. albicans, which suggests that EA/HP-β-CD may be a promising alternative for the treatment of oral candidiasis.

Influence of Pre-Harvest Gibberellic Acid and Post-Harvest 1-methyl Cyclopropane Treatments on Phenolic Compounds, Vitamin C and Organic Acid Contents during the Shelf Life of Strawberry Fruits

In recent years, significant portions of the fresh fruits and vegetables produced worldwide have been decaying before reaching the consumer because of insufficient preservation after harvest. In this direction, we carried the study out to investigate the effect of gibberellic acid (GA3) and 1-methyl cyclopropane (1-MCP) applications on phenolic compounds and organic acid contents of the strawberry fruits (cv. Albion) during shelf-life. Gibberellic acid treatments, which prepared in two different concentrations (50 and 100 ppm), were performed by spraying the leaves before harvest. 1-methyl cyclopropane applied after harvest. The results of the study showed a greater decrease in organic acids (except oxalic and succinic acid) in Gibberellic acid-applied fruits during shelf-life. Citric acid was recorded as the most abundant organic acid in the control group. In phenolic compounds, gallic acid (15.22 mg 100 g-1) and ellagic acid (9.38 mg 100 g-1) were recorded as the highest phenolic compounds on the third day. 1-MCP and GA3 (50 ppm) + 1-MCP treatment reduced the breakdown of vitamin C during the shelf-life of strawberry fruits compared to the control group. As a result, phenolic compounds, vitamin C, and organic acids decreased during the shelf-life, and 1-MCP applications slowed down the breakdown of these compounds.

Combination of ellagic acid and trans-cinnamaldehyde alleviates aging-induced cognitive impairment via modulation of mitochondrial function and inflammatory and apoptotic mediators in the prefrontal cortex of aged rats

Cognitive impairments are associated with advancing age. Trans-cinnamaldehyde (CIN) and ellagic acid (ELA) have multiplex activities to reduce various age-related cognitive disorders. In this study, we investigated the effects of these compounds separately or in combination on the cognitive outcomes, mitochondrial function, and inflammatory and apoptotic mediators in aged male Wistar rats. Thirty-two old (22 months old) and eight young (5 months old) rats were randomly allocated to five groups of young control, aged control, ELA-aged, CIN-aged, and ELA + CIN-aged. ELA (15 mg/kg, orally) and CIN (50 mg/kg, intraperitoneally) separately or in combination were administered for 1 month in aged animals. Spatial memory and cognitive activity were evaluated by the Barnes maze and novel object recognition tests. Mitochondrial function (its reactive oxygen species [ROS], mitochondrial membrane potential and ATP level), pro-inflammatory cytokines such as interleukin (IL)-1β and IL-6 and pro-apoptotic caspase 3 and Bax, and anti-apoptotic Bcl2 levels and their ratio were assessed in the prefrontal cortex. Behavioral results revealed that CIN separately or in combination with ELA significantly alleviates aging-induced memory impairment. Moreover, co-administration of agents effectively decreased inflammatory cytokines, cleaved-caspase 3, Bax and Bax/Bcl2 levels, mitochondrial ROS production, and mitochondrial membrane depolarization and increased Bcl2 and ATP level as compared with untreated aged control rats. Combination therapy was greater than those of individual treatments in all parameters. Therefore, combination therapy with CIN and ELA improved aging-induced cognitive impairment through anti-inflammatory, anti-apoptotic, and mitochondrial-boosting effects in aged rats.

Ellagic acid ameliorates neuroinflammation and demyelination in experimental autoimmune encephalomyelitis: Involvement of NLRP3 and pyroptosis

Multiple sclerosis (MS) is presented as the most common autoimmune and demyelinating neurological disorder with incapacitating complications and with no definite therapy. Most treatments for MS mainly focus on attenuation of its severity and recurrence. To model MS reliably to study pathogenesis and efficacy of possible chemicals, experimental autoimmune encephalomyelitis (EAE) condition is induced in rodents. Ellagic acid is a neuroprotective polyphenol that can protect against demyelination. This study was planned and conducted to assess its possible beneficial effect in MOG-induced EAE model of MS with emphasis on uncovering its modes of action. Ellagic acid was given p.o. (at doses of 10 or 50 mg/kg/day) after development of clinical signs of MS to C57BL/6 mice immunized with MOG_35-55. Results showed that ellagic acid can ameliorate severity of the disease and partially restore tissue level of TNFα, IL-6, IL-17A and IL-10. Besides, ellagic acid lowered tissue levels of NLRP3 and caspase 1 in addition to its mitigation of neuroinflammation, demyelination and axonal damage in spinal cord specimens of EAE group. As well, ellagic acid treatment prevented reduction of MBP and decreased GFAP and Iba1 immunoreactivity. Taken together, ellagic acid can decrease severity of EAE via amelioration of astrogliosis, astrocyte activation, demyelination, neuroinflammation and axonal damage that is partly related to its effects on NLRP3 inflammasome and pyroptotic pathway.

Physical formulation approaches for improving aqueous solubility and bioavailability of ellagic acid: A review

Ellagic acid (EA) is a polyphenolic active compound with antimalarial and other promising therapeutic activities. However, its solubility and its permeability are both low (BCS IV). These properties greatly compromise its oral bioavailability and clinical utilizations. To overcome these limitations of the physicochemical parameters, several formulation approaches, including particle size reduction, amorphization and lipid-based formulations, have been used. Although these strategies have not yet led to a clinical application, some of them have resulted in significant improvements in the solubility and bioavailability of EA. This critical review reports and analyses the different formulation approaches used by scientists to improve both the biopharmaceutical properties and the clinical use of EA.

Bud-Derivatives, a Novel Source of Polyphenols and How Different Extraction Processes Affect Their Composition

The use of herbal food supplements, as a concentrate form of vegetable extracts, increased so much over the past years to count them among the relevant sources of dietetic polyphenols. Bud-derivatives are a category of botanicals perceived as a "new entry" in this sector since they are still poorly studied. Due to the lack of a manufacturing process specification, very different products can be found on the market in terms of their polyphenolic profile depending on the experimental conditions of manufacturing. In this research two different manufacturing processes, using two different protocols, and eight species (Carpinus betulus L., Cornus mas L., Ficus carica L., Fraxinus excelsior L., Larix decidua Mill., Pinus montana Mill., Quercus petraea (Matt.) Liebl., Tilia tomentosa Moench), commonly used to produce bud-derivatives, have been considered as a case study. An untargeted spectroscopic fingerprint of the extracts, coupled to chemometrics, provide to be a useful tool to identify these botanicals. The targeted phytochemical fingerprint by HPLC provided a screening of the main bud-derivatives polyphenolic classes highlighting a high variability depending on both method and protocol used. Nevertheless, ultrasonic extraction proved to be less sensitive to the different extraction protocols than conventional maceration regarding the extract polyphenolic profile.

Strategies to improve ellagic acid bioavailability: from natural or semisynthetic derivatives to nanotechnological approaches based on innovative carriers

Ellagic acid (EA) is a polyphenolic compound whose dietary consumption is mainly associated with the intake of red fruits, including pomegranates, strawberries, blackberries, blackcurrants, raspberries, grapes or dried fruits, like walnuts and almonds. A number of studies indicate that EA exerts health-beneficial effects against several chronic pathologies associated with oxidative damage, including different kinds of cancer, cardiovascular and neurodegenerative diseases. Furthermore, EA possesses wound-healing properties, antibacterial and antiviral effects, and acts as a systemic antioxidant. However, clinical applications of this polyphenol have been hampered and prevented by its poor water solubility (9.7 ± 3.2 μg ml^-1 in water) and pharmacokinetic profile (limited absorption rate and plasma half-life <1 h after ingestion of pomegranate juice), properties due to the chemical nature of the organic heterotetracyclic compound. Little has been reported on efficient strategies to enhance EA poor oral bioavailability, including chemical structure modifications, encapsulation within nano-microspheres to be used as carriers, and molecular dispersion in polymer matrices. In this review we summarize the experimental approaches investigated so far in order to improve EA pharmacokinetics, supporting the hypothesis that enhancement in EA solubility is a feasible route for increasing its oral absorption.

Oxidative Stress, Antioxidant Capabilities, and Bioavailability: Ellagic Acid or Urolithins?

Oxidative stress (OS), triggered by overproduction of reactive oxygen and nitrogen species, is the main mechanism responsible for several human diseases. The available one-target drugs often face such illnesses, by softening symptoms without eradicating the cause. Differently, natural polyphenols from fruits and vegetables possess multi-target abilities for counteracting OS, thus representing promising therapeutic alternatives and adjuvants. Although in several in vitro experiments, ellagitannins (ETs), ellagic acid (EA), and its metabolites urolithins (UROs) have shown similar great potential for the treatment of OS-mediated human diseases, only UROs have demonstrated in vivo the ability to reach tissues to a greater extent, thus appearing as the main molecules responsible for beneficial activities. Unfortunately, UROs production depends on individual metabotypes, and the consequent extreme variability limits their potentiality as novel therapeutics, as well as dietary assumption of EA, EA-enriched functional foods, and food supplements. This review focuses on the pathophysiology of OS; on EA and UROs chemical features and on the mechanisms of their antioxidant activity. A discussion on the clinical applicability of the debated UROs in place of EA and on the effectiveness of EA-enriched products is also included.