Pharmacokinetic study of ellagic acid in rat after oral administration of pomegranate leaf extract

Unlocking the therapeutic treasure of pomegranate leaf: A comprehensive review on phytochemical compounds, health benefits, and future prospects

The exploration of sustainable and valuable by-products from industrial and agricultural processes is increasingly recognized for its economic, environmental and health advantages. This review examines the phytochemical constituents, biological properties, current applications and future directions of pomegranate (Punica granatum L.) leaf (PGL). PGL exhibits broad biological activities, aiding in managing health conditions like chronic diseases, cancer, diabetes, obesity, and neurological disorders. Anti-cancer and anti-diabetic effects are demonstrated in vitro and in vivo using animal models. Anti-inflammatory and neuroprotective properties are also observed in cell cultures and animal studies. Its anti-microbial properties show efficacy against pathogens. However, variability in phytochemical composition due to different extraction methods and environmental conditions poses challenges for standardization. The review underscores the urgent need for comprehensive human clinical trials to confirm PGL's therapeutic benefits and safety, calling for future research to fully harness PGL's potential as a sustainable and bioactive compound in various industrial applications.

Urolithin A, induces apoptosis and autophagy crosstalk in Oral Squamous Cell Carcinoma via mTOR /AKT/ERK1/2 pathway

BACKGROUND

Oral squamous cell carcinoma (OSCC) is the most prevalent malignancy in the world with an alarming rate of mortality. Despite the advancement in treatment strategies and drug developments, the overall survival rate remains poor. Therefore, it is imperative to develop alternative or complimentary anti cancer drugs with minimum off target effects. Urolithin A, a microbial metabolite of ellagic acid and ellagitannins produced endogenously by human gut micro biome is considered to have anti-cancerous activity. However anti tumorigenic effect of urolithin A in OSCC is yet to be elucidated. In this study, we examined whether urolithin A inhibits cell growth and induces both apoptosis and autophagy dependent cell death in OSCC cell lines.

PURPOSE

The present study aims to evaluate the potential of urolithin A to inhibit OSCC and its regulatory effect on OSCC proliferation and invasion in vitro and in vivo mouse models.

METHODS

We evaluated whether urolithin A could induce cell death in OSCC in vitro and in vivo mouse models.

RESULTS

Flow cytometric and immunoblot analysis on Urolithin A treated OSCC cell lines revealed that urolithin A markedly induced cell death of OSCC via the induction of endoplasmic reticulum stress and subsequent inhibition of AKT and mTOR signaling as evidenced by decreased levels of phosphorylated mTOR and 4EBP1. This further revealed a possible cross talk between apoptotic and autophagic signaling pathways. In vivo study demonstrated that urolithin A treatment reduced tumor size and showed a decrease in mTOR, ERK1/2 and Akt levels along with a decrease in proliferation marker, Ki67. Taken together, in vitro as well as our in vivo data indicates that urolithin A is a potential anticancer agent and the inhibition of AKT/mTOR/ERK signalling is crucial in Urolithin A induced growth suppression in oral cancer.

CONCLUSION

Urolithin A exerts its anti tumorigenic activity through the induction of apoptotic and autophagy pathways in OSCC. Our findings suggest that urolithin A markedly induced cell death of oral squamous cell carcinoma via the induction of endoplasmic reticulum stress and subsequent inhibition of AKT and mTOR signaling as evidenced by decreased levels of phosphorylated mTOR and 4EBP1. Urolithin A remarkably suppressed tumor growth in both in vitro and in vivo mouse models signifying its potential as an anticancer agent in the prevention and treatment of OSCC. Henceforth, our findings provide a new insight into the therapeutic potential of urolithin A in the prevention and treatment of OSCC.

Oral supplementation of Gordonibacter urolithinfaciens promotes ellagic acid metabolism and urolithin bioavailability in mice

Ellagic acid (EA) is an abundant dietary polyphenol with multifarious health benefits but low bioavailability. To increase its bio-efficacy, converting EA to urolithins by supplementing urolithin-producing bacteria, e.g., Gordonibacter urolithinfaciens (G.uro), could be a solution. This work first tested three methods for oral delivery of live G.uro. Intestinal colonization of G.uro and its impact on local gut microbiota, EA-to-urolithin conversion and bioavailability were then investigated in C57BL/6J mice administered to EA only or a synbiotic (G. uro + EA). In vitro results suggested that G.uro largely survived simulated gastrointestinal digestion and could be administered without protection. In vivo results showed that G.uro had little impact on local gut microbiota but could not colonize the gut. Moreover, synbiotic remarkably promoted Akkermansia, Lactobacillus and Bifidobacterium growth, and significantly enhanced the bioavailability of urolithins compared with the EA-only group. This study demonstrated the potential of oral supplementation of G.uro for enhancing EA-to-urolithin bioconversion and bioavailability.

Chestnut Wood Tannins in Broiler Diets: Pharmacokinetics, Serum Levels during Rearing, and Intestinal Absorption Pattern of Gallic Acid

Studies on the bioavailability, serum levels, and absorption of hydrolyzable tannin compounds are lacking. In this study, we performed a pharmacokinetic trial, measured the serum levels of compounds in broilers that were reared with different feed added or not with tannins, and tested the digestibility of tannins throughout the intestinal tract. Only gallic acid and 4-O-methyl gallic acid were found in the serum. Moreover, gallic acid showed a 41.8% absolute oral bioavailability and a 72.3% relative bioavailability of gallic acid from chestnut extract compared to the standard. The rapid metabolization caused alternating serum levels during the day and night. These patterns were not affected by the feed type or the previous addition of tannins in the feed. The absorption and metabolization in the intestines occurred gradually throughout the intestinal tract. The latter was true for gallic acid as well as ellagic acid, which was not found in the serum. We can conclude that components from chestnut tannins are absorbed throughout all components of the intestinal tract and are eliminated quickly with little interaction from the feed and previous addition of tannins. Moreover, ellagic acid seems to be absorbed but would remain accumulated in the intestinal tissue or be metabolized by the microbiome.

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.

The effect of ellagic acid on the metabolic syndrome: A review article

Objective

(s): Metabolic syndrome is a collection of metabolic abnormalities that includes hyperglycemia, dyslipidemia, hypertension, and obesity. Ellagic acid is found in various fruits and vegetables. It has been reported to have several pharmacological properties, such as antibacterial, antifungal, antiviral, anti-inflammatory, hepatoprotective, cardioprotective, chemopreventive, neuroprotective, gastroprotective, and antidiabetic. Our current study aims to shed light on the probable efficiency of ellagic acid in managing metabolic syndrome and its complications.

Materials and methods

To prepare the present review, the databases or search engines utilized included Scopus, PubMed, Science Direct, and Google Scholar, and relevant articles have been gathered with no time limit until March 2023.

Results

Several investigations indicated that ellagic acid could be a potent compound for the treatment of many disorders such as diabetes, hypertension, and hyperlipidemia by various mechanisms, including increasing insulin secretion, insulin receptor substrate protein 1 expression, regulating glucose transporter 4, triglyceride, total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), attenuating tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), reactive oxygen species (ROS), malondialdehyde (MDA), and oxidative stress in related tissues. Furthermore, ellagic acid ameliorates mitochondrial function, upregulates uncoupling protein 1 (found in brown and white adipose tissues), and regulates blood levels of nitrate/nitrite and vascular relaxations in response to acetylcholine and sodium nitroprusside.

Conclusion

Ellagic acid can treat or manage metabolic syndrome and associated complications, according to earlier studies. To validate the beneficial effects of ellagic acid on metabolic syndrome, additional preclinical and clinical research is necessary.

An Overview of the Health Benefits, Extraction Methods and Improving the Properties of Pomegranate

Pomegranate (Punica granatum L.) is a polyphenol-rich edible food and medicinal plant of ancient origin, containing flavonols, anthocyanins, and tannins, with ellagitannins as the most abundant polyphenols. In the last decades, its consumption and scientific interest increased, due to its multiple beneficial effects. Pomegranate is a balausta fruit, a large berry surrounded by a thick colored peel composed of exocarp and mesocarp with edible arils inside, from which the pomegranate juice can be produced by pressing. Seeds are used to obtain the seed oil, rich in fatty acids. The non-edible part of the fruit, the peel, although generally disposed as a waste or transformed into compost or biogas, is also used to extract bioactive products. This review summarizes some recent preclinical and clinical studies on pomegranate, which highlight promising beneficial effects in several fields. Although further insight is needed on key aspects, including the limited oral bioavailability and the role of possible active metabolites, the ongoing development of suitable encapsulation and green extraction techniques enabling the valorization of waste pomegranate products point to the great potential of pomegranate and its bioactive constituents as dietary supplements or adjuvants in therapies of cardiovascular and non-cardiovascular diseases.

Promising remedies for cardiovascular disease: Natural polyphenol ellagic acid and its metabolite urolithins

BACKGROUND

Cardiovascular disease (CVD) is a significant worldwide factor contributing to human fatality and morbidity. With the increase of incidence rates, it is of concern that there is a lack of current therapeutic alternatives because of multiple side effects. Ellagic acid (EA), the natural polyphenol (C₁₄H₆O₈), is abundant in pomegranates, berries, and nuts. EA and its intestinal microflora metabolite, urolithins, have recently attracted much attention as a potential novel "medicine" because of their wide pharmacological properties.

PURPOSE

This study aimed to critically analyze available literature to summarize the beneficial effects of EA and urolithins, and highlights their druggability and therapeutic potential in various CVDs.

METHODS

We systematically studied research and review articles between 1984 and 2022 available on various databases to obtain the data on EA and urolithins with no language restriction. Their cardiovascular protective activities, underlying mechanism, and druggability were highlighted and discussed comprehensively.

RESULTS

We found that EA and urolithins may exert preventive and curative effects on CVD with negligible side effects and possibly regulate lipid metabolism imbalance, pro-inflammatory factor production, vascular smooth muscle cell proliferation, cardiomyocyte apoptosis, endothelial cell dysfunction, and Ca²⁺ intake and release. Potentially, this may lead to the prevention and amelioration of atherosclerosis, hypertension, myocardial infarction, cardiac fibrosis, cardiomyopathy, cardiac arrhythmias, and cardiotoxicities in vivo. Several molecules and signaling pathways are associated with their therapeutic actions, including phosphatidylinositol 3-kinase/protein kinase B, mitogen-activated protein kinase, NF-κB, nuclear factor erythroid-2 related factor 2, sirtuin1, miRNA, and extracellular signal-regulated kinase 1/2.

CONCLUSION

In vitro and in vivo studies shows that EA and urolithins could be used as valid candidates for early prevention and effective therapeutic strategies for various CVDs.

Novel assay to measure chromosome instability identifies Punica granatum extract that elevates CIN and has a potential for tumor- suppressing therapies

Human artificial chromosomes (HACs) have provided a useful tool to study kinetochore structure and function, gene delivery, and gene expression. The HAC propagates and segregates properly in the cells. Recently, we have developed an experimental high-throughput imaging (HTI) HAC-based assay that allows the identification of genes whose depletion leads to chromosome instability (CIN). The HAC carries a GFP transgene that facilitates quantitative measurement of CIN. The loss of HAC/GFP may be measured by flow cytometry or fluorescence scanning microscope. Therefore, CIN rate can be measured by counting the proportion of fluorescent cells. Here, the HAC/GFP-based assay has been adapted to screen anticancer compounds for possible induction or elevation of CIN. We analyzed 24 cytotoxic plant extracts. Punica granatum leaf extract (PLE) indeed sharply increases CIN rate in HT1080 fibrosarcoma cells. PLE treatment leads to cell cycle arrest, reduction of mitotic index, and the increased numbers of micronuclei (MNi) and nucleoplasmic bridges (NPBs). PLE-mediated increased CIN correlates with the induction of double-stranded breaks (DSBs). We infer that the PLE extract contains a component(s) that elevate CIN, making it a candidate for further study as a potential cancer treatment. The data also provide a proof of principle for the utility of the HAC/GFP-based system in screening for natural products and other compounds that elevate CIN in cancer cells.

Natural Blockers of PD-1/PD-L1 Interaction for the Immunotherapy of Triple-Negative Breast Cancer-Brain Metastasis

The limited treatment options for triple-negative breast cancer with brain metastasis (TNBC-BM) have left the door of further drug development for these patients wide open. Although immunotherapy via monoclonal antibodies has shown some promising results in several cancers including TNBC, it cannot be considered the most effective treatment for brain metastasis. This is due to the protective role of the blood-brain barrier (BBB) which limits the entrance of most drugs, especially the bulky ones such as antibodies, to the brain. For a drug to traverse the BBB via passive diffusion, various physicochemical properties should be considered. Since natural medicine has been a key inspiration for the development of the majority of current medicines, in this paper, we review several naturally-derived molecules which have the potential for immunotherapy via blocking the interaction of programmed cell death protein-1 (PD-1) and its ligand, PD-L1. The mechanism of action, physicochemical properties and pharmacokinetics of these molecules and their theoretical potential to be used for the treatment of TNBC-BM are discussed.

Protection Against Drug-Induced Liver Injuries Through Nutraceuticals via Amelioration of Nrf-2 Signaling

Hepatotoxicity caused by the overdose of various medications is a leading cause of drug-induced liver injury. Overdose of drugs causes hepatocellular necrosis. Nutraceuticals are reported to prevent drug-induced liver failure. The present article aims to review the protection provided by various medicinal plants against hepatotoxic drugs. Ayurveda is considered a conventional restorative arrangement in India. It is consistently used for ages and is still used today to cure drug-induced hepatotoxicity by focusing on antioxidant stress response pathways such as the nuclear factor erythroid-2 (Nrf-2) antioxidant response element signaling pathway. Nrf-2 is a key transcription factor that entangles Kelch-like ECH-associating protein 1, a protein found in the cell cytoplasm. Some antioxidant enzymes, such as gamma glycine cysteine ligase (γ-GCL) and heme oxygenase-1 (HO-1), are expressed in Nrf-2 targeted genes. Their expression, in turn, decreases the stimulation of hepatic macrophages and induces the messenger RNA (mRNA) articulation of proinflammatory factors including tumor necrosis factor α. This review will cover various medicinal plants from a mechanistic view and how they stimulate and interact with Nrf-2, the master regulator of the antioxidant response to counterbalance oxidative stress. Interestingly, therapeutic plants have become popular in the medical sector due to safer yet effective supplementation for the prevention and treatment of new human diseases. The contemporary study is expected to collect information on a variety of therapeutic traditional herbs that have been studied in the context of drug-induced liver toxicity, as nutraceuticals are the most effective treatments for oxidative stress-induced hepatotoxicity. They are less genotoxic, have a lower cost, and are readily available. Together, nutraceuticals exert protective effects against drug-induced hepatotoxicity through the inhibition of oxidative stress, inflammation, and apoptosis. Its mechanism(s) are considered to be associated with the γ-GCL/HO-1 and Nrf-2 signaling pathways. KEY TEACHING POINTSThe liver is the most significant vital organ that carries out metabolic activities of the body such as the synthesis of glycogen, the formation of triglycerides and cholesterol, as well as the formation of bile.Acute liver failure is caused by the consumption of certain drugs; drug-induced liver injury is the major condition.The chemopreventive activity of nutraceuticals may be related to oxidative stress reduction and attenuation of biosynthetic processes involved in hepatic injury via amelioration of the nuclear factor erythroid-2 (Nrf-2) signaling pathway.Nrf-2 is a key transcription factor that is found in the cell cytoplasm resulting in the expression of various genes such as gamma glycine cysteine ligase and heme oxygenase-1.Nutraceutical-rich phytochemicals possess high antioxidant activity, which helps in the prevention of hepatic injury.

Urolithin B suppressed osteoclast activation and reduced bone loss of osteoporosis via inhibiting ERK/NF-κB pathway

Objectives

The main target of current drugs for alleviating bone loss is osteoclasts. However, the long‐term application of such drugs will also cause side effects. Therefore, it is of great need to develop new and safer therapeutics for osteoporosis. In recent years, drug development based on gut microbiota has gradually attracted attention. This manuscript investigates the inhibitory effect of urolithin B (UB) on osteoclastogenesis and differentiation in vitro and in ovariectomized (OVX) mice.

Materials and Methods

CCK‐8 was used to analyse the cytotoxicity of UB; BMMs cells were differentiated into osteoclasts by RANKL, and respectively treated with 1, 5, and 25 μmol/L UB during this process. After one week of intervention, tartrate‐resistant acid phosphatase (TRAP) staining was used to analyse the number and average area of osteoclasts. F‐actin staining and immunofluorescence staining were conducted to evaluate the morphology and function of osteoclasts. Bone resorption function of osteoclasts was detected by Pit Formation Assay. The expression of osteoclast‐related protein genes in RAW264.7 cells were investigated via western blot and RT‐PCR assays. Western blot analysis of RANKL‐mediated activation of MAPK/NF‐κB pathway after 0, 5, 15, 30, 60 min of intervention. For in vivo experiments, OVX mice received intraperitoneal injection of 10, 50 mg/kg every two days, 8 weeks later, the femurs of mice were taken for morphological analysis, and the serum content of CTX‐1, a bone metabolism index, was analysed.

Results

UB could inhibit the osteoclast differentiation of rankl‐induced bone marrow macrophages (BMMs) and RAW264.7 cells in vitro, suppress the uptake activity of hydroxyapatite and expression of osteoclast‐related gene MMP9, CTSK, NFATc1 and c‐fos. Furthermore, UB repressed the rankl‐induced phosphorylation and degradation of IκB and the phosphorylation of P65 in the NF‐κB pathway of RAW264.7 cells, and also down‐regulated the phosphorylation level of ERK in the MAPK pathway. For in vivo studies, UB‐treated OVX mice showed more significant improved various parameters of distal femur compared with the control group, with fewer NFATc1, MMP9 and TRAP‐positive osteoclasts in bone tissues, and less serum content of CTX‐1.

Conclusion

Urolithin B attenuated bone loss in OVX mice by inhibiting the formation and activation of osteoclasts via down‐regulation of the ERK/NF‐κB signalling pathway.

Pharmacokinetics study of a supersaturatable self-microemulsifying drug delivery system for ellagic acid by UHPLC-Q-TOF-MS

To evaluate the bioavailability of ellagic acid loaded super-saturatable self-microemulsifying drug delivery system (S-SMEDDS), its pharmacokinetic properties were studied in rats with an ultra-high performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry. The plasma samples were treated by solid-phase extraction method, and gallic acid was used as the internal standard when determining the concentration of ellagic acid. Results showed that the established analytical method was sensitive and accurate, which is applicable to the pharmacokinetic study of ellagic acid. The drug was found to be absorbed rapidly in vivo, and the plasma concentration-time curve showed double peaks, indicating that ellagic acid were reabsorbed by entero-hepatic circulation after oral administration. Compared with ellagic acid suspension, the apparent clearance of ellagic acid-loaded S-SMEDDS and SMEDDS reduced significantly, and the AUC _0~t of them were 4.7 and 5.8-fold increase, respectively. Therefore, the bioavailability of ellagic acid-loaded S-SMEDDS was higher than that of the suspension and SMEDDS.

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.

Natural Phytochemicals as Novel Therapeutic Strategies to Prevent and Treat Parkinson's Disease: Current Knowledge and Future Perspectives

Parkinson's disease (PD) is the second-most common neurodegenerative chronic disease affecting both cognitive performance and motor functions in aged people. Yet despite the prevalence of this disease, the current therapeutic options for the management of PD can only alleviate motor symptoms. Research has explored novel substances for naturally derived antioxidant phytochemicals with potential therapeutic benefits for PD patients through their neuroprotective mechanism, targeting oxidative stress, neuroinflammation, abnormal protein accumulation, mitochondrial dysfunction, endoplasmic reticulum stress, neurotrophic factor deficit, and apoptosis. The aim of the present study is to perform a comprehensive evaluation of naturally derived antioxidant phytochemicals with neuroprotective or therapeutic activities in PD, focusing on their neuropharmacological mechanisms, including modulation of antioxidant and anti-inflammatory activity, growth factor induction, neurotransmitter activity, direct regulation of mitochondrial apoptotic machinery, prevention of protein aggregation via modulation of protein folding, modification of cell signaling pathways, enhanced systemic immunity, autophagy, and proteasome activity. In addition, we provide data showing the relationship between nuclear factor E2-related factor 2 (Nrf2) and PD is supported by studies demonstrating that antiparkinsonian phytochemicals can activate the Nrf2/antioxidant response element (ARE) signaling pathway and Nrf2-dependent protein expression, preventing cellular oxidative damage and PD. Furthermore, we explore several experimental models that evaluated the potential neuroprotective efficacy of antioxidant phytochemical derivatives for their inhibitory effects on oxidative stress and neuroinflammation in the brain. Finally, we highlight recent developments in the nanodelivery of antioxidant phytochemicals and its neuroprotective application against pathological conditions associated with oxidative stress. In conclusion, naturally derived antioxidant phytochemicals can be considered as future pharmaceutical drug candidates to potentially alleviate symptoms or slow the progression of PD. However, further well-designed clinical studies are required to evaluate the protective and therapeutic benefits of phytochemicals as promising drugs in the management of PD.

An Overview on Dietary Polyphenols and Their Biopharmaceutical Classification System (BCS)

Polyphenols are natural organic compounds produced by plants, acting as antioxidants by reacting with ROS. These compounds are widely consumed in daily diet and many studies report several benefits to human health thanks to their bioavailability in humans. However, the digestion process of phenolic compounds is still not completely clear. Moreover, bioavailability is dependent on the metabolic phase of these compounds. The LogP value can be managed as a simplified measure of the lipophilicity of a substance ingested within the human body, which affects resultant absorption. The biopharmaceutical classification system (BCS), a method used to classify drugs intended for gastrointestinal absorption, correlates the solubility and permeability of the drug with both the rate and extent of oral absorption. BCS may be helpful to measure the bioactive constituents of foods, such as polyphenols, in order to understand their nutraceutical potential. There are many literature studies that focus on permeability, absorption, and bioavailability of polyphenols and their resultant metabolic byproducts, but there is still confusion about their respective LogP values and BCS classification. This review will provide an overview of the information regarding 10 dietarypolyphenols (ferulic acid, chlorogenic acid, rutin, quercetin, apigenin, cirsimaritin, daidzein, resveratrol, ellagic acid, and curcumin) and their association with the BCS classification.

Effect of Gut Microbiota Biotransformation on Dietary Tannins and Human Health Implications

Tannins represent a heterogeneous group of high-molecular-weight polyphenols that are ubiquitous among plant families, especially in cereals, as well as in many fruits and vegetables. Hydrolysable and condensed tannins, in addition to phlorotannins from marine algae, are the main classes of these bioactive compounds. Despite their low bioavailability, tannins have many beneficial pharmacological effects, such as anti-inflammatory, antioxidant, antidiabetic, anticancer, and cardioprotective effects. Microbiota-mediated hydrolysis of tannins produces highly bioaccessible metabolites, which have been extensively studied and account for most of the health effects attributed to tannins. This review article summarises the effect of the human microbiota on the metabolism of different tannin groups and the expected health benefits that may be induced by such mutual interactions. Microbial metabolism of tannins yields highly bioaccessible microbial metabolites that account for most of the systemic effects of tannins. This article also uses explainable artificial intelligence to define the molecular signatures of gut-biotransformed tannin metabolites that are correlated with chemical and biological activity. An understanding of microbiota-tannin interactions, tannin metabolism-related phenotypes (metabotypes) and chemical tannin-metabolites motifs is of great importance for harnessing the biological effects of tannins for drug discovery and other health benefits.

An Overview of Nanoformulated Nutraceuticals and their Therapeutic Approaches

Background:

Economic development and vast changes in food habits have accelerated the consumption of junk foods, which are the leading causes of several disorders that turn the majority of the people to use various herbal formulations or drugs for preventing various lifestyle diseases. Nutraceuticals are the borderline apparatus between nutrients and drugs that provide supplementation of the particular nutrient with a favorable health effect.

Objective:

Various nutraceutical compounds like vitamins, spices, polyphenols, prebiotics, and probiotics in the form of powders, tablets, and capsules are currently marketed globally. Among them, previous literature have reported that polyphenols are the most promising compounds that have been proven to treat various chronic diseases like cancer, hypertension, diabetes mellitus (DM), osteoporosis, osteoarthritis, dyslipidemia, multiple sclerosis, congenital anomalies, Alzheimer’s disease, etc. It is warranted to discuss the benefits of nanoformulations of nutraceuticals.

Methods:

We have searched PubMed using the keywords nutraceuticals, nanoformulations, therapeutic approaches, bionanotechnology, and therapeutics. The relevant papers and classical papers in this field were selected to write this review.

Results and Discussion:

The different classifications of nutraceuticals were described in this review. The comparison between the different categories of nutraceuticals with their nanoformulated forms was made, explaining the benefits of nanoformulations regarding stability, bioavailability, enhanced anti-oxidant properties, etc. A glimpse of the drawbacks of nanoformulations was also included.

Conclusion:

The current review highlights an overview of various nanoformulated nutraceuticals and their approach towards the treatment of multiple diseases.

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.

Pectin-Based Formulations for Controlled Release of an Ellagic Acid Salt with High Solubility Profile in Physiological Media

Among bioactive phytochemicals, ellagic acid (EA) is one of the most controversial because its high antioxidant and cancer-preventing effects are strongly inhibited by low gastrointestinal absorption and rapid excretion. Strategies toward an increase of solubility in water and bioavailability, while preserving its structural integrity and warranting its controlled release at the physiological targets, are therefore largely pursued. In this work, EA lysine salt at 1:4 molar ratio (EALYS), exhibiting a more than 400 times increase of water solubility with respect to literature reports, was incorporated at 10% in low methoxylated (LM) and high methoxylated (HM) pectin films. The release of EA in PBS at pH 7.4 from both film preparations was comparable and reached 15% of the loaded compound over 2 h. Under simulated gastric conditions, release of EA from HM and LM pectin films was minimal at gastric pH, whereas higher concentrations—up to 300 μM, corresponding to ca. 50% of the overall content—were obtained in the case of the HM pectin film after 2 h incubation at the slightly alkaline pH of small intestine environment, with the enzyme and bile salt components enhancing the release. EALYS pectin films showed a good prebiotic activity as evaluated by determination of short chain fatty acids (SCFAs) levels following microbial fermentation, with a low but significant increase of the effects produced by the pectins themselves. Overall, these results highlight pectin films loaded with EALYS salt as a promising formulation to improve administration and controlled release of the compound.

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.

Chitosan-Based Microparticles Enhance Ellagic Acid's Colon Targeting and Proapoptotic Activity

This study aimed at improving the targeting and cytotoxic effect of ellagic acid (EA) on colon cancer cells. EA was encapsulated in chitosan (CHIT) polymers then coated by eudragit S100 (ES100) microparticles. The release of EA double-coated microparticles (MPs) was tested at simulative pH values. Maximum release was observed at 24 h and pH 7.4. The cytotoxicity of EA MPs on HCT 116 colon cancer cells was synergistically improved as compared with raw EA. Cell-cycle analysis by flow cytometry suggested enhanced G2-M phase colon cancer cell accumulation. In addition, a significantly higher cell fraction was observed in the pre-G phase, which highlighted the enhancement of the proapoptotic activity of EA formulated in the double-coat mixture. Annexin-V staining was used for substantiation of the observed cell-death-inducing activity. Cell fractions were significantly increased in early, late, and total cell death. This was backed by high elevation in cellular content of caspase 3. Effectiveness of the double-coated EA to target colonic tissues was confirmed using real-time iohexol dye X-ray radiography. In conclusion, CHIT loaded with EA and coated with ES100 formula exhibits improved colon targeting as well as enhanced cytotoxic and proapoptotic activity against HCT 116 colon cancer when compared with the administration of raw EA.

Nanoformulated ellagic acid ameliorates pentylenetetrazol-induced experimental epileptic seizures by modulating oxidative stress, inflammatory cytokines and apoptosis in the brains of male mice

The present study evaluated the neuroprotective and antiepileptic efficacy of ellagic acid (EA) encapsulated in calcium-alginate nanoparticles (Ca²⁺-ALG NPs) in pentylenetetrazol (PTZ)-induced seizures in male mice. EA was encapsulated in ALG NPs using a nanospray drying method followed by ionotropic crosslinking with Ca²⁺. Characterization of the developed Ca²⁺-crosslinked EA-ALG NPs showed spherical, high stability NPs; successful loading of EA within crosslinked ALG NPs; and sustained release of EA. Male Swiss albino mice were divided into ten groups as follows; Group I- (control), Group II (50 mg EA /kg) - (EA), Group III polyethylene glycol (PEG), Group IV EA NPs (50 mg/kg) - (EA NP), Group (50 mg/kg alginate) V void V NPs - (void NPs), Group VI: (37.5 PTZ mg/kg) -(PTZ), Group VII: PTZ and EA - (PTZ-EA). Group VIII: animals received PTZ and PEG concurrently (PTZ-PEG). Group IX; animals received PTZ and void NPs concurrently - (PTZ-void). Group X: animals received PTZ and EA NPs concurrently (PTZ-EA NPs). PTZ was used to induce experimental epilepsy. Ca²⁺-ALG NPs prevented seizures throughout the experimental period and had a more prominent effect than free EA did. Ca²⁺-ALG NPs prevented increased glutamate, decreased GABA concentrations and ameliorated increased amyloid-β and homocysteine levels in the serum and brain. Ca²⁺-EA-ALG NPs were superior to free EA in improving increased IL-6 and TNF-α. Ca²⁺-ALG NPs ameliorated PTZ-induced oxidative stress, as evidenced by decreased 4HNE levels and enhanced GSH, GR and GPx levels in the brain. These changes were accompanied by amelioration of apoptosis and its regulating proteins, including Cytochrome C, P53, Bax, Bcl2 and caspase-3 and caspase-9, and protected against DNA damage. Histological examination of the hippocampus confirmed that the neuroprotective effect of Ca²⁺-EA-ALG NPs was superior and more effective than that of free EA.

Carpinus turczaninowii Extract May Alleviate High Glucose-Induced Arterial Damage and Inflammation

Hyperglycemia-induced oxidative stress triggers severe vascular damage and induces an inflammatory vascular state, and is, therefore, one of the main causes of atherosclerosis. Recently, interest in the natural compound Carpinus turczaninowii has increased because of its reported antioxidant and anti-inflammatory properties. We investigated whether a C. turczaninowii extract was capable of attenuating high glucose-induced inflammation and arterial damage using human aortic vascular smooth muscle cells (hASMCs). mRNA expression levels of proinflammatory response [interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α)], endoplasmic reticulum (ER) stress [CCAAT-enhancer-binding proteins (C/EBP) homologous protein (CHOP)], and adenosine monophosphate (AMP)-protein activated kinase α2 (AMPK α2)], and DNA damage [phosphorylated H2.AX (p-H2.AX)] were measured in hASMCs treated with the C. turczaninowii extracts (1 and 10 μg/mL) after being stimulated by high glucose (25 mM) or not. The C. turczaninowii extract attenuated the increased mRNA expression of IL-6, TNF-α, and CHOP in hASMCs under high glucose conditions. The expression levels of p-H2.AX and AMPK α2 induced by high glucose were also significantly decreased in response to treatment with the C. turczaninowii extract. In addition, 15 types of phenolic compounds including quercetin, myricitrin, and ellagic acid, which exhibit antioxidant and anti-inflammatory properties, were identified in the C. turczaninowii extract through ultra-performance liquid chromatography-quadrupole-time of flight (UPLC-Q-TOF) mass spectrometry. In conclusion, C. turczaninowii may alleviate high glucose-induced inflammation and arterial damage in hASMCs, and may have potential in the treatment of hyperglycemia-induced atherosclerosis.

Effects of Black Raspberries and Their Ellagic Acid and Anthocyanin Constituents on Taxane Chemotherapy of Castration-Resistant Prostate Cancer Cells

Cancer patients often use dietary supplements while on therapy, but little is known about interactions of supplements with cancer chemotherapy. Black raspberries (BRB) have anti-cancer effects, but have not been evaluated for interference with chemotherapy for castrate-resistant prostate cancer (CRPC). Here we studied whether BRB and some of their constituents interact with docetaxel and cabazitaxel on CRPC cells in culture and implanted into nude mice. Ellagic acid increased, but BRB extract inhibited, microtubule assembly. Ellagic acid decreased tubulin polymerization by cabazitaxel and bound to tubulin. Ellagic acid, its metabolite urolithin A, BRB extract, and the anthocyanin metabolite protocatechuic acid (PCA) did not alter cytotoxicity of taxanes. Ellagic acid inhibited drug efflux in CRPC cells, but BRB extract and PCA did not. None of these compounds altered CYP3A4 activity. Although dietary ellagic acid did not alter the tumor growth inhibition by docetaxel of xenografted 22Rv1 cells, ellagic acid has the potential to interfere with taxane chemotherapy by reducing tubulin polymerization while inhibiting P-glycoprotein drug efflux. These data are cause for concern of consuming ellagic acid during treatment for CRPC and indicate need for further research, but BRB consumption appears safe.

Improvement of post-thawed sperm quality in broiler breeder roosters by ellagic acid-loaded liposomes

Liposomes could improve the delivery of substances to sperm. This study was conducted to investigate the effect of the antioxidant ellagic acid and ellagic acid-loaded liposomes on post-thawed sperm quality in broiler breeder roosters. Semen was diluted in Beltsville extender containing ellagic acid or ellagic acid-loaded liposomes (ellagic acid at 0 (control), 0.5, 1, and 2 mM) and cryopreserved. Sperm quality was evaluated post-thawing: motility characteristics (Computer-Assisted Semen Analysis), membrane functionality (HOS test), abnormal morphology, mitochondrial activity (Rhodamine 123), apoptotic status (Annexin V/Propidium iodide), malondialdehyde, and antioxidant activities (glutathione peroxidase (GPx), superoxide dismutase (SOD), and total antioxidant capacity (TAC)). The results showed that 1 mM ellagic acid-loaded liposomes improved total motility, membrane functionality, and viability comparing to 0.5 and 2 mM ellagic acid, 2 mM ellagic acid-loaded liposomes, and control group. Mitochondrial activity was significantly higher for 1 mM ellagic acid-loaded liposomes compared to the rest of the treatments, except 1 mM ellagic acid. Ellagic acid at 1 mM in both forms significantly increased GPx and TAC after freeze-thawing (no significant variation for SOD), and also yielded the lower proportion of apoptotic and dead cells. In conclusion, ellagic acid improved post-thawed sperm quality in broiler breeder roosters. The use of liposomes could further enhance the effects of ellagic acid.

Urolithin A, a Novel Natural Compound to Target PI3K/AKT/mTOR Pathway in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy and is highly resistant to standard treatment regimens. Targeted therapies against KRAS, a mutation present in an overwhelming majority of PDAC cases, have been largely ineffective. However, inhibition of downstream components in the KRAS signaling cascade provides promising therapeutic targets in the management of PDAC and warrants further exploration. Here, we investigated Urolithin A (Uro A), a novel natural compound derived from pomegranates, which targets numerous kinases downstream of KRAS, in particular the PI3K/AKT/mTOR signaling pathways. We showed that treatment of PDAC cells with Uro A blocked the phosphorylation of AKT and p70S6K in vitro, successfully inhibited the growth of tumor xenografts, and increased overall survival of Ptf1a^Cre/+;LSL-Kras^G12D/+;Tgfbr2^flox/flox (PKT) mice compared with vehicle or gemcitabine therapy alone. Histologic evaluation of these Uro A-treated tumor samples confirmed mechanistic actions of Uro A via decreased phosphorylation of AKT and p70S6K, reduced proliferation, and increased cellular apoptosis in both xenograft and PKT mouse models. In addition, Uro A treatment reprogrammed the tumor microenvironment, as evidenced by reduced levels of infiltrating immunosuppressive cell populations such as myeloid-derived suppressor cells, tumor-associated macrophages, and regulatory T cells. Overall, this work provides convincing preclinical evidence for the utility of Uro A as a therapeutic agent in PDAC through suppression of the PI3K/AKT/mTOR pathway.

Ellagic acid attenuates arsenic induced neuro-inflammation and mitochondrial dysfunction associated apoptosis

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Ellagic acid mitigates arsenic mediated genotoxicity in rat brain hippocampi.

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Ellagic acid ameliorates arsenic induced exacerbation in levels of ROS and pro-inflammatory cytokines in rat brain hippocampi.

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Ellagic acid has the propensity to modulate mRNA expression of BAX, Bcl₂ and caspase3, suggestive of its neuroprotective efficacy.

Arsenic, being a global pollutant needs a potential remedy which could fight against its associated toxicities. Ellagic acid (EA) is a known agent for its anti-inflammatory, antioxidant and antiapoptotic effects, and it is commonly found in fruits. The present study is designed to determine protective efficacy of EA against arsenic induced toxicity with special mention to inflammation and mitochondrial dysfunction in hippocampi of wistar rats. Rats were pre-treated with EA (20 and 40 mg/kg b.wt; p.o. for 11 days) along with arsenic (10 mg/kg; p.o. for 8 days). Total reactive oxygen species level and mitochondrial membrane potential were analyzed using flow cytometry. Protein and mRNA expression of apoptotic and inflammatory markers were also evaluated in rat hippocampus. Our results show that arsenic exposure increased total ROS generation and DNA fragmentation, decreased mitochondrial membrane potential alongwith an increase in expression of pro-apoptotic and inflammatory markers. suggesting that EA complementation downregulated total ROS generation dose dependently. Apoptotic markers, BAX and Bcl₂ as well as inflammatory markers, IL-1β, TNFα, INFγ got altered significantly on its administration. Moreover, it also attenuated effects on mitochondrial membrane potential. Based on our findings, EA might substantiate to be a budding therapeutic candidate against arsenic induced neurotoxicity.

Neuroprotective effects of ellagic acid on cuprizone-induced acute demyelination through limitation of microgliosis, adjustment of CXCL12/IL-17/IL-11 axis and restriction of mature oligodendrocytes apoptosis

CONTEXT

Ellagic acid (EA) is a natural phenol antioxidant with various therapeutic activities. However, the efficacy of EA has not been examined in neuropathologic conditions.

OBJECTIVE

In vivo neuroprotective effects of EA on cuprizone (cup)-induced demyelination were evaluated.

MATERIAL AND METHODS

C57BL/6 J mice were fed with chow containing 0.2% cup for 4 weeks to induce oligodendrocytes (OLGs) depletion predominantly in the corpus callosum (CC). EA was administered at different doses (40 or 80 mg/kg body weight/day/i.p.) from the first day of cup diet. Oligodendrocytes apoptosis [TUNEL assay and myelin oligodendrocyte glycoprotein (MOG+)/caspase-3+ cells), gliosis (H&E staining, glial fibrillary acidic protein (GFAP+) and macrophage-3 (Mac-3+) cells) and inflammatory markers (interleukin 17 (IL-17), interleukin 11 (IL-11) and stromal cell-derived factor 1 α (SDF-1α) or CXCL12] during cup intoxication were examined.

RESULTS

High dose of EA (EA-80) increased mature oligodendrocytes population (MOG+ cells, p < 0.001), and decreased apoptosis (p < 0.05) compared with the cup mice. Treatment with both EA doses did not show any considerable effects on the expression of CXCL12, but significantly down-regulated the expression of IL-17 and up-regulated the expression of IL-11 in mRNA levels compared with the cup mice. Only treatment with EA-80 significantly decreased the population of active macrophage (MAC-3+ cells, p < 0.001) but not reactive astrocytes (GFAP+ cells) compared with the cup mice.

DISCUSSION AND CONCLUSION

In this model, EA-80 effectively reduces lesions via reduction of neuroinflammation and toxic effects of cup on mature OLGs. EA is a suitable therapeutic agent for moderate brain damage in neurodegenerative diseases such as multiple sclerosis.

Enhanced anticancer activity and oral bioavailability of ellagic acid through encapsulation in biodegradable polymeric nanoparticles

Despite the fact that various studies have investigated the clinical relevance of ellagic acid (EA) as a naturally existing bioactive substance in cancer therapy, little has been reported regarding the efficient strategy for improving its oral bioavailability. In this study, we report the formulation of EA-loaded nanoparticles (EA-NPs) to find a way to enhance its bioactivity as well as bioavailability after oral administration. Poly(ε-caprolactone) (PCL) was selected as the biodegradable polymer for the formulation of EA-NPs through the emulsion–diffusion–evaporation technique. The obtained NPs have been characterized by measuring particle size, zeta potential, Fourier transform infrared, differential scanning calorimetry, and X-ray diffraction. The entrapment efficiency and the release profile of EA was also determined. In vitro cellular uptake and cytotoxicity of the obtained NPs were evaluated using Caco-2 and HCT-116 cell lines, respectively. Moreover, in vivo study has been performed to measure the oral bioavailability of EA-NPs compared to free EA, using New Zealand white rabbits. NPs with distinct shape were obtained with high entrapment and loading efficiencies. Diffusion-driven release profile of EA from the prepared NPs was determined. EA-NP-treated HCT-116 cells showed relatively lower cell viability compared to free EA-treated cells. Fluorometric imaging revealed the cellular uptake and efficient localization of EA-NPs in the nuclear region of Caco-2 cells. In vivo testing revealed that the oral administration of EA-NPs produced a 3.6 times increase in the area under the curve compared to that of EA. From these results, it can be concluded that incorporation of EA into PCL as NPs enhances its oral bioavailability and activity.

Representative literature on the phytonutrients category: Phenolic acids

Research concerning the benefits derived from dietary polyphenols, a significant class within the family of phytonutrients, has increased considerably in the last decade. Prior to the late 1990s, the nutritional spotlight focused on the antioxidant capabilities of carotenoids, vitamins, and minerals. More recently, however, research has emerged in strong support of the antioxidant capacity of polyphenols and their role in the prevention and/or treatment of certain cancers, diabetes, cardiovascular diseases, and inflammation. Polyphenols are categorized according to the nature of their carbon skeleton, ranging from basic phenolic molecules to highly complex compounds, such as flavonoids, the most common and widely studied of all phenolic compounds. The most prevalent phenolic acids include ellagic acid, gallic acid, tannic acid, and capsaicin.

Polyphenol-Rich Extract of Syzygium cumini Leaf Dually Improves Peripheral Insulin Sensitivity and Pancreatic Islet Function in Monosodium L-Glutamate-Induced Obese Rats

Syzygium cumini (L.) Skeels (Myrtaceae) has been traditionally used to treat a number of illnesses. Ethnopharmacological studies have particularly addressed antidiabetic and metabolic-related effects of extracts prepared from its different parts, especially seed, and pulp-fruit, however. there is a lack of studies on phytochemical profile and biological properties of its leaf. As there is considerable interest in bioactive compounds to treat metabolic syndrome and its clustered risk factors, we sought to characterize the metabolic effects of hydroethanolic extract of S. cumini leaf (HESc) on lean and monosodium L-glutamate (MSG)-induced obese rats. HPLC-MS/MS characterization of the HESc polyphenolic profile, at 254 nm, identified 15 compounds pertaining to hydrolysable tannin and flavanol subclasses. At 60 days of age, both groups were randomly assigned to receive HESc (500 mg/kg) or vehicle for 30 days. At the end of treatment, obese+HESc exhibited significantly lower body weight gain, body mass index, and white adipose tissue mass, compared to obese rats receiving vehicle. Obese rats treated with HESc showed a twofold increase in lipolytic activity in the periepididymal fat pad, as well as, brought triglyceride levels in serum, liver and skeletal muscle back to levels close those found in lean animals. Furthermore, HESc also improved hyperinsulinemia and insulin resistance in obese+HESc rats, which resulted in partial reversal of glucose intolerance, as compared to obese rats. HESc had no effect in lean rats. Assessment of ex vivo glucose-stimulated insulin secretion showed HESc potentiated pancreatic function in islets isolated from both lean and obese rats treated with HESc. In addition, HESc (10–1000 μg/mL) increased glucose stimulated insulin secretion from both isolated rat islets and INS-1E β-cells. These data demonstrate that S. cumini leaf improved peripheral insulin sensitivity via stimulating/modulating β-cell insulin release, which was associated with improvements in metabolic outcomes in MSG-induced obese rats.

The Effects of Ellagic Acid upon Brain Cells: A Mechanistic View and Future Directions

Ellagic acid (EA, 2,3,7,8-tetrahydroxy-chromeno; C14H6O8) is a polyphenol derived from fruits (pomegranates, berries) and nuts. EA exhibits antioxidant capacity and induces anti-inflammatory actions in several mammalian tissues. EA has been characterized as a possible neuroprotective agent, but the number of reports is still limited to conclude whether and how EA exerts neuroprotection in humans. In this regard, performing additional studies considering the potential beneficial and/or toxicological roles for EA on brain cells would be an important step towards fully understanding of when and how EA may be securely utilized by humans as a neuroprotective agent. The aim of the present work is to discuss data related to the neuronal and glial effects of EA and the mechanisms underlying such events. Moreover, future directions are suggested as a potential guide to be utilized by researchers interested in investigating the neuronal and glial actions of EA hereafter.

In Vitro Bioaccessibility, Human Gut Microbiota Metabolites and Hepatoprotective Potential of Chebulic Ellagitannins: A Case of Padma Hepaten® Formulation

Chebulic ellagitannins (ChET) are plant-derived polyphenols containing chebulic acid subunits, possessing a wide spectrum of biological activities that might contribute to health benefits in humans. The herbal formulation Padma Hepaten containing ChETs as the main phenolics, is used as a hepatoprotective remedy. In the present study, an in vitro dynamic model simulating gastrointestinal digestion, including dialysability, was applied to estimate the bioaccessibility of the main phenolics of Padma Hepaten. Results indicated that phenolic release was mainly achieved during the gastric phase (recovery 59.38%-97.04%), with a slight further release during intestinal digestion. Dialysis experiments showed that dialysable phenolics were 64.11% and 22.93%-26.05% of their native concentrations, respectively, for gallic acid/simple gallate esters and ellagitanins/ellagic acid, in contrast to 20.67% and 28.37%-55.35% for the same groups in the non-dialyzed part of the intestinal media. Investigation of human gut microbiota metabolites of Padma Hepaten and pure ChETs (chebulinic, chebulagic acids) established the formation of bioactive urolithins (A, B, C, D, M5). The fact of urolithin formation during microbial transformation from ChETs and ChET-containing plant material was revealed for the first time. Evaluation of the protective effect of ChETs colonic metabolites and urolithins on tert-butyl hydroperoxide (t-BHP)-induced oxidative injury in cultured rat primary hepatocytes demonstrated their significant reversion of the t-BHP-induced cell cytotoxicity, malonic dialdehyde production and lactate dehydrogenase leakage. The most potent compound was urolithin C with close values of hepatoprotection to gallic acid. The data obtained indicate that in the case of Padma Hepaten, we speculate that urolithins have the potential to play a role in the hepatic prevention against oxidative damage.

Pomegranate inhibits neuroinflammation and amyloidogenesis in IL-1β-stimulated SK-N-SH cells

PURPOSE

Pomegranate fruit, Punica granatum L. (Punicaceae), and its constituents have been shown to inhibit inflammation. In this study, we aimed to assess the effects of freeze-dried pomegranate (PWE) on PGE2 production in IL-1β-stimulated SK-N-SH cells.

METHODS

An enzyme immunoassay (EIA) was used to measure prostaglandin E2 (PGE2) production from supernatants of IL-1β-stimulated SK-N-SH cells. Expression of COX-2, phospho-IκB, and phospho-IKK proteins was evaluated, while NF-κB reporter gene assay was carried out in TNFα-stimulated HEK293 cells to determine the effect of PWE on NF-κB transactivation. Levels of BACE-1 and Aβ in SK-N-SH cells stimulated with IL-1β were measured with an in cell ELISA.

RESULTS

PWE (25-200 μg/ml) dose dependently reduced COX-2-dependent PGE2 production in SK-N-SH cells stimulated with IL-1β. Phosphorylation of IκB and IKK was significantly (p < 0.001) inhibited by PWE (50-200 μg/ml). Our studies also show that PWE (50-200 μg/ml) significantly (p < 0.01) inhibited NF-κB transactivation in TNFα-stimulated HEK293 cells. Furthermore, PWE inhibited BACE-1 and Aβ expression in SK-N-SH cells treated with IL-1β.

CONCLUSIONS

Taken together, our study demonstrates that pomegranate inhibits inflammation, as well as amyloidogenesis in IL-1β-stimulated SK-N-SH cells. We propose that pomegranate is a potential nutritional strategy in slowing the progression of neurodegenerative disorders such as Alzheimer's disease.

Self nanoemulsifying drug delivery system of stabilized ellagic acid-phospholipid complex with improved dissolution and permeability

Ellagic acid (EA), a plant polyphenol known for its wide-range of health benefits has limited use due to its low oral bioavailability. In this study, a new self-nanoemulsifying drug delivery system (SNEDDS), based on the phospholipid complex technique, was developed to improve the oral bioavailability of ellagic acid. Ellagic acid-phospholipid complex was prepared by an anti-solvent method and characterized. Enhanced lipophilicity after the formation of ellagic acid-phospholipid complex was verified through solubility studies. Preliminary screening was carried out to select oil, surfactant and co-surfactant. Ternary phase diagrams were constructed to identify the area of nanoemulsification. Formulations were optimized on the basis of globule size, cloud point and robustness to dilution. The optimized SNEDDS of ellagic acid-phospholipid complex showed mean globule size of 106 ± 0.198 nm and cloud point at 83-85 °C. The in vitro drug release from SNEDDS was found to be higher compared to EA suspension and complex, while ex vivo studies showed increased permeation from SNEDDS compared to EA suspension. Moreover, SNEDDS overcome the food effect which was shown by EA suspension. Thus, SNEDDS were found to be influential in improving the release performance of EA, indicating their potential to improve the oral bioavailability of EA.

Preparation and characterization of micronized ellagic acid using antisolvent precipitation for oral delivery

In this work, poorly water soluble phytochemical ellagic acid (EA) was micronized to increase its solubility and thereby the bioavailability during antisolvent precipitation process using N-methyl pyrrolidone (NMP) as solvent and deionized water as antisolvent. The micronized EA (m-EA) freeze-dried powder was prepared by the subsequent lyophilization process. The effects of various experimental parameters on the mean particle size (MPS) of m-EA suspension (m-EAS) in the antisolvent precipitation process were investigated. MPS and production efficiency were taken into account comprehensively to obtain the optimum conditions of antisolvent precipitation. Under the optimum conditions, m-EA freeze-dried powder with a MPS of 429.2 ± 7.6 nm was obtained. The physico-chemical properties of m-EA freeze-dried powder were detected by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), liquid chromatography-tandem mass spectrometry (LC-MS/MS), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The results indicated m-EA kept the same chemical structure with raw EA, but the crystallinity was greatly reduced. Furthermore, a comparison of the 50% inhibition concentration (IC50) values revealed that m-EA was more effective than raw EA in scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. Meanwhile, m-EA also showed higher reducing power. Moreover, the residual amount of NMP was lower than the International Conference on Harmonization limit (530 ppm) for solvents. The dissolution rate of m-EA was approximately 2 times of raw EA. Moreover, the solubility of m-EA was about 6.5 times of raw EA. Meanwhile, the bioavailability of m-EA increased about 2 times compared with raw EA via oral administration.

JAK2 and AMP-kinase inhibition in vitro by food extracts, fractions and purified phytochemicals

A study of 49 foods shows that ellagitannin containing foods inhibit JAK2 and AMPK kinases.

Method development and validation for pharmacokinetic and tissue distributions of ellagic acid using ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS)

Ellagic acid is a dietary polyphenol found in numerous fruits and vegetables, possessing several health benefits such as antioxidant, anticancer and anti-atherosclerotic biological properties. The purpose of this study was to explore the pharmacokinetics and tissue distribution of ellagic acid in rats. A simple, rapid, sensitive and specific liquid chromatography–tandem mass spectrometry method to determine the ellagic acid in plasma and tissue samples was developed and validated. The separation was achieved using reversed-phase ultra-performance liquid chromatography (UPLC), and the mass spectrometric detection was achieved using heated electrospray ionization (negative mode) and multiple ion monitoring (m/z 301/229). A sample cleanup with a solid phase extraction (SPE) step prior to the UPLC-MS/MS analysis was also developed. The SPE and UPLC-MS/MS method established here was successfully applied to reveal the pharmacokinetic profiles and tissue distribution of ellagic acid. After oral administration dosing at 50 mg/kg, plasma levels of ellagic acid peaked at about 0.5 h, with C_max value of 93.6 ng/mL, and the results showed that the ellagic acid was poorly absorbed after oral administration. The pharmacokinetic profile of ellagic acid fitted to a two-compartment model with t_1/2α 0.25 h and t_1/2β 6.86 h, respectively. Following oral administration, ellagic acid was detected in all examined tissues including kidney, liver, heart, lung and brain et al., and the highest levels were found in kidney and liver.

Involvement of L-arginine/NO/cGMP/K(ATP) channel pathway in the peripheral antinociceptive actions of ellagic acid in the rat formalin test

The present study was conducted to evaluate the local antinociceptive actions of EA and the possible involvement of l-arginine/NO/cGMP/KATP channel pathway in this effect using formalin test in rats. To evaluate the involvement of l-arginine/NO/cGMP/KATP channel pathway in the antinociceptive action of EA, rats were pre-treated intraplantarlly with l-NAME (NOS inhibitor, 25-100μg/paw), methylene blue (guanylyl cyclase inhibitor, 100-400μg/paw), glibenclamide (ATP-sensitive K(+) channel blocker, 25-100μg/paw), l-arginine (a nitric oxide precursor, 25-100μg/paw) and sodium nitroprusside (125-500μg/paw). The local peripheral ipsilateral, but not contralateral, administration of EA into the right paw (30-300μg/paw) produced a dose-related antinociception during both early and late phases of formalin test which is comparable with morphine (25μg/paw). Moreover, local pre-treatment with l-NAME, methylene blue and glibenclamide dose-dependently prevented EA (100μg/paw)-induced antinociception in late phase. Additionally, administration of l-arginine and sodium nitroprusside significantly potentiated the antinociception induced by EA in the late phase. However, these treatments had no significant effect on antinociceptive response of EA in the early phase of the formalin test. The results of the present study showed that EA-induced local peripheral antinociception during the both phases of formalin test. Also, our data suggested the activation of the l-arginine/NO/cGMP/KATP channels pathway in EA-induced antinociception in late phase of formalin test. Topical application of EA by ointment or jelly might be a useful method to relieving the inflammatory pain states.