Exploring the Potential of Ellagic Acid in Gastrointestinal Cancer Prevention: Recent Advances and Future Directions

Gastrointestinal (GI) cancers are a significant global health concern with diverse etiologies and limited treatment options. Ellagic acid (EA), a natural polyphenolic compound, exhibits promising anticancer properties against various GI malignancies. In this article, we have reviewed recent research on the anticancer potential of EA across esophageal, gastric, colorectal, pancreatic, and liver cancers. In esophageal cancer, EA inhibits the formation of O6-methylguanine (O6-meGua) adducts induced by carcinogens like N-nitrosomethylbenzylamine (NMBA), thereby suppressing tumor growth. Additionally, EA inhibits STAT3 signaling and stabilizes tumor suppressor proteins, showing potential as an anti-esophageal cancer agent. In gastric cancer, EA regulates multiple pathways involved in cell proliferation, invasion, and apoptosis, including the p53 and PI3K-Akt signaling pathways. It also demonstrates anti-inflammatory and antioxidant effects, making it a promising therapeutic candidate against gastric cancer. In colorectal cancer (CRC), EA inhibits cell proliferation, induces apoptosis, and modulates the Wnt/β-catenin and PI3K/Akt pathways, suggesting its efficacy in preventing CRC progression. Furthermore, EA has shown promise in pancreatic cancer by inhibiting nuclear factor-kappa B, inducing apoptosis, and suppressing epithelial-mesenchymal transition. In liver cancer, EA exhibits radio-sensitizing effects, inhibits inflammatory pathways, and modulates the tumor microenvironment, offering potential therapeutic benefits against hepatocellular carcinoma. Studies on EA potential in combination therapies and the development of targeted delivery systems are required for enhanced efficacy against gastrointestinal cancers.

Ellagic acid improves the symptoms of early-onset Alzheimer's disease: Behavioral and physiological correlates

Oryza sativa is a globally recognized staple food, rich in essential phyto-phenolic compounds such as γ-Oryzanol (OZ), Ferulic acid (FA), and Ellagic acid (EA). These phytochemicals are known for their potential to beneficially modulate molecular biochemistry. The present investigation aimed to evaluate the neuroprotective and cognitive enhancement effects of Oryza sativa phyto-phenolics in a model of early-onset Alzheimer's disease (EOAD) induced by Aβ (1-42) in animals. In-silico studies suggested that FA, OZ, and EA have target specificity for Aβ, with EA being further selected based on its potent in-vitro Aβ anti-aggregatory effects for exploring neurodegenerative conditions. The in-vivo experiments demonstrated that EA exerts therapeutic effects in Aβ-induced EOAD, modulating both biochemical and behavioral outcomes. EA treatment at two dose levels, EA70 and EA140 (70 μM and 140 μM, respectively, administered i.c.v.), significantly counteracted Aβ aggregation and modulated the Ca2⁺/Calpain/GSK-3β/CDK5 signaling pathways, exhibiting anti-tauopathy effects. Additionally, EA was shown to exert anti-inflammatory effects by preventing astroglial activation, modulating FAIM-L expression, and protecting against TNF-α-induced apoptotic signals. Moreover, the neuromodulatory effects of EA were attributed to the regulation of CREB levels, Dnm-1 expression, and synaptophysin levels, thereby enhancing LTP and synaptic plasticity. EA also induced beneficial cytological and behavioral changes, improving both long-term and short-term spatial memory as well as associative learning behavior in the animal model, which underscores its cognitive enhancement properties.

Hydrolyzable Tannins in the Management of Th1, Th2 and Th17 Inflammatory-Related Diseases

Plants rich in hydrolyzable tannins were traditionally used all over the world for a variety of chronic inflammatory disorders, including arthritis, colitis, and dermatitis. However, the knowledge of their immunological targets is still limited though fundamental for their rational use in phytotherapy. The recent advances regarding the pathogenesis of inflammatory-based diseases represent an opportunity to elucidate the pharmacological mechanism of plant-derived metabolites with immunomodulatory activity. This review collects recent articles regarding the role of hydrolyzable tannins and their gut metabolites in Th1, Th2, and Th17 inflammatory responses. In line with the traditional use, rheumatoid arthritis (RA), inflammatory bowel diseases (IBDs), psoriasis, atopic dermatitis (AD), and asthma were the most investigated diseases. A substantial body of in vivo studies suggests that, beside innate response, hydrolyzable tannins may reduce the levels of Th-derived cytokines, including IFN-γ, IL-17, and IL-4, following oral administration. The mode of action is multitarget and may involve the impairment of inflammatory transcription factors (NF-κB, NFAT, STAT), enzymes (MAPKs, COX-2, iNOS), and ion channels. However, their potential impact on pathways with renewed interest for inflammation, such as JAK/STAT, or the modulation of the gut microbiota demands dedicate studies.

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.

The Alleviating Effect of Lagerstroemia indica Flower Extract on Stretch Marks through Regulation of Mast Cells

Striae distensae (SD) or stretch marks are common linear scars of atrophic skin with disintegrating extracellular matrix (ECM) structures. Although fibroblasts contribute to the construction of ECM structure in SD, some studies have reported that mast cell degranulation causes the disruption of ECM in early SD lesions. Lagerstroemia indica flower (LIF) has traditionally been used in India as a diuretic. However, little is known about the effect and molecular action of Lagerstroemia indica flower extract (LIFE) on alleviating SD. This study evaluated the effects of LIFE on mast cell degranulation and the synthesis of ECM components in fibroblasts. LIFE inhibits the adhesion of rat basophilic leukemia (RBL) cells, RBL-2H3 on fibronectin (FN) and the expression of integrin, a receptor for FN, thereby reducing focal adhesion kinase (FAK) phosphorylation. In addition, LIFE attenuated the allergen-induced granules and cytokine interleukin 3 (IL-3) through the adhesion with FN. Moreover, the conditioned medium (CM) of activated mast cells decreases the synthesis of ECM components, and LIFE restores the abnormal expressions induced by activated mast cells. These results demonstrate that LIFE suppresses FN-induced mast cell activation and promotes the synthesis of ECM components in fibroblast, which indicates that LIFE may be a useful cosmetic agent for SD treatment.

Camu-Camu Fruit Extract Inhibits Oxidative Stress and Inflammatory Responses by Regulating NFAT and Nrf2 Signaling Pathways in High Glucose-Induced Human Keratinocytes

Myrciaria dubia (HBK) McVaugh (camu-camu) belongs to the family Myrtaceae. Although camu-camu has received a great deal of attention for its potential pharmacological activities, there is little information on the anti-oxidative stress and anti-inflammatory effects of camu-camu fruit in skin diseases. In the present study, we investigated the preventative effect of 70% ethanol camu-camu fruit extract against high glucose-induced human keratinocytes. High glucose-induced overproduction of reactive oxygen species (ROS) was inhibited by camu-camu fruit treatment. In response to ROS reduction, camu-camu fruit modulated the mitogen-activated protein kinases (MAPK)/activator protein-1 (AP-1), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and nuclear factor of activated T cells (NFAT) signaling pathways related to inflammation by downregulating the expression of proinflammatory cytokines and chemokines. Furthermore, camu-camu fruit treatment activated the expression of nuclear factor E2-related factor 2 (Nrf2) and subsequently increased the NAD(P)H:quinone oxidoreductase1 (NQO1) expression to protect keratinocytes against high-glucose-induced oxidative stress. These results indicate that camu-camu fruit is a promising material for preventing oxidative stress and skin inflammation induced by high glucose level.

Pharmacological Benefits of Triphala: A Perspective for Allergic Rhinitis

Allergic rhinitis (AR) is considered a major nasal condition impacting a large number of people around the world, and it is now becoming a global health problem. Because the underlying mechanisms of AR are complex, the development of single-drug treatment might not be enough to treat a wide spectrum of the disease. Although the standard guidelines classify and provide suitable diagnosis and treatment, the vast majority of people with AR are still without any means of controlling it. Moreover, the benefits of AR drugs are sometimes accompanied by undesirable side effects. Thus, it is becoming a significant challenge to find effective therapies with limited undesirable side effects for a majority of patients suffering from uncontrolled AR. Aller-7/NR-A2, a polyherbal formulation, has revealed promising results in patients by reducing nasal symptoms and eosinophil counts without serious adverse effects. Interestingly, three out of seven of the herbals in the Aller-7/NR-A2 formulation are also found in an Ayurvedic polyherbal formulation known as “Triphala,” which is a potential candidate for the treatment of AR. However, there are no current studies that have examined the effects of Triphala on the disease. This review aims to describe the complexity of AR pathophysiology, currently available treatments, and the effects of Triphala on AR in order to help develop it as a promising alternative treatment in the future.

CHEMICAL CONSTITUENTS OF GEUM RIVALE L. AND THEIR BIOLOGICAL ACTIVITY

The aim of the study is to review the literature data on the chemical constituents of arial and underground parts of Geum rivale L. (Rosaceae) and the pharmacological activity of its extracts and individual compounds.

Materials and methods. The study was carried out using Internet resources (Google Scholar, PubMed) and library databases (e-Library, Scopus, Web of Science). The main research methods were a review and analysis of the literature data on the topic for the period from 1958 up to the present.

Results. For the period from 1958 up to the present more than 80 components in the arial and underground parts of G. rivale have been identified.  Among them there were components of the essential oil, phenolic acids and coumarins, aglycones of flavonoids, including luteolin, apigenin, quercetin and kaempferol, as well as a number of their glycosides and glucuronides, ellagitannins (hemin A, B, C, D, pedunculagin, stachiurin/casuarinin, tellimagrandin I). Some aspects of the pharmacological activity of total extracts and individual secondary metabolites of G. rivale have been studied, anti-inflammatory, antioxidant, antimicrobial, antiviral activities have been experimentally confirmed.

Conclusion. The analysis of the literature data showed that a further study of the composition of metabolites of G. rivale and their pharmacological activity is an urgent task, the solution of which will expand the range of use of this plant in medical practice and consider G. rivale as a promising source of pharmaceutical substances for the creation of new drugs and biologically active additives.

The polyphenol ellagic acid exerts anti-inflammatory actions via disruption of store-operated calcium entry (SOCE) pathway activators and coupling mediators

Ellagic acid, a naturally occurring phenol found in a variety of fruits and nuts has been shown to possess anti-inflammatory properties. However, the mechanism of action behind its anti-inflammatory action is unclear. Using human Jurkat T cells, our study examined the effects of ellagic acid (EA) on Ca²⁺ handling, in particular, store-operated Ca²⁺ entry (SOCE), a process critical to proper T cell function. We observed that the acute addition of EA-induced Ca²⁺ release with an EC₅₀ of 63 μM. The Ca²⁺ release was significantly attenuated by Xestospongin C, a known inhibitor of the Inositol 1,4,5-trisphosphate receptor (IP₃R) channel and was unaffected by the phospholipase C (PLC) inhibitor, U73122. Furthermore, chronic incubation of Jurkat T cells with EA not only decreased the ATP-induced Ca²⁺ release but also diminished the SOCE-mediated Ca²⁺ influx in a dose-dependent manner. This inhibition was confirmed by reduced Mn²⁺ entry rates in the EA-treated cells. The ATP-induced Ca²⁺ entry was also attenuated in EA-treated HEK293 cells transiently transfected with SOCE channel Orai1-myc and ER-sensor stromal interaction molecule (STIM1) (HEK^STIM/Orai). Moreover, EA treatment interfered with the Orai1 and STIM1 coupling by disrupting STIM1 puncta formation in the HEK^STIM/Orai cells. We observed that EA treatment reduced cytokine secretion and nuclear factor of activated T-cell transcriptional activity in stimulated T cells. Hence, by inhibiting SOCE mediated Ca²⁺ influx, EA decreased downstream activation of pro-inflammatory mediators. These results suggest a novel target for EA-mediated effects and provide insight into the mechanisms underlying EA-mediated anti-inflammatory effects.

Anti-Atopic Effect of Acorn Shell Extract on Atopic Dermatitis-Like Lesions in Mice and Its Active Phytochemicals

To investigate the potential effects of acorn shells on atopic dermatitis (AD), we utilized oxazolone (OX)- or 2,4-dinitrochlorobenzene (DNCB)-induced AD-like lesion mouse models. Our research demonstrates that Acorn shell extract (ASE) improved the progression of AD-like lesions, including swelling, which were induced by oxazolone on Balb/c mouse ears. Additionally, ASE significantly decreased the ear thickness (OX: 0.42 ± 0.01 mm, OX-ASE: 0.32 ± 0.02 mm) and epidermal thickness (OX: 75.3 ± 32.6 µm, OX-ASE: 46.1 ± 13.4 µm). The continuous DNCB-induced AD mouse model in SKH-1 hairless mice demonstrated that ASE improved AD-like symptoms, including the recovery of skin barrier dysfunction, Immunoglobulin E hyperproduction (DNCB: 340.1 ± 66.8 ng/mL, DNCB-ASE: 234.8 ± 32.9 ng/mL) and an increase in epidermal thickness (DNCB: 96.4 ± 21.9 µm, DNCB-ASE: 52.4 ± 16.3 µm). In addition, we found that ASE suppressed the levels of AD-involved cytokines, such as Tumor Necrosis Factor α, IL-1β, IL-25 and IL-33 in both animal models. Furthermore, gallic acid and ellagic acid isolated from ASE suppressed β-hexosaminidase release and IL-4 expression in RBL-2H3 cells. The acorn shell and its active phytochemicals have potential as a new remedy for the improvement of atopic dermatitis and other inflammatory diseases.

Inhibitory effect of ethanol extract of Ampelopsis brevipedunculata rhizomes on atopic dermatitis-like skin inflammation

ETHNOPHARMACOLOGICAL RELEVANCE

Extracts from various parts of Ampelopsis brevipedunculata has been used as anti-inflammatory agents in Asian folk medicine.

AIM OF THE STUDY

To demonstrate the medicinal effect of the A. brevipedunculata in skin inflammation, specifically atopic dermatitis (AD).

MATERIALS AND METHODS

The effect of ethanol extract of A. brevipedunculata rhizomes (ABE) on AD was examined using an AD-like skin inflammation model induced by repeated exposure to house dust mite (Dermatophagoides farinae extract, DFE) and 2,4-dinitrochlorobenzene (DNCB). The mechanism study was performed using tumor necrosis factor (TNF)-α and interferon (IFN)-γ-activated human keratinocytes (HaCaT). Serum histamine and immunoglobulin levels were quantified using enzymatic kits, while the gene expression of cytokines and chemokines was analyzed using quantitative real time polymerase chain reaction. The expression of signaling molecules was detected using Western blot.

RESULTS

Oral administration of ABE alleviated DFE/DNCB-induced ear thickening and clinical symptoms, as well as immune cell infiltration (mast cells and eosinophils) into the dermal layer. Serum Immunoglobulin (Ig) E, DFE-specific IgE, IgG2a, and histamine levels were decreased after the administration of ABE. ABE also inhibited CD4⁺IFN-γ⁺ and CD4⁺IL-4⁺ lymphocyte polarization in lymph nodes and expression of TNF-α, IFN-γ, IL-4, IL-13, and IL-31 in the ear tissue. In TNF-α/INF-γ-stimulated keratinocytes, ABE inhibited the gene expression of TNF-α, IL-6, IL-1β, and CCL17. In addition, ABE decreased the nuclear localization of signal transducer and activator of transcription 1 and nuclear factor-κB, and the phosphorylation of extracellular signal-regulated kinase and p38 mitogen-activated protein kinase.

CONCLUSION

Collectively, our data demonstrate the pharmacological role and signaling mechanism of ABE in the regulation of skin allergic inflammation, which supports our suggestion that ABE could be developed as a potential therapeutic agent for the treatment of AD.

Alkali-soluble pectin suppresses IgE production in human myeloma cell line in vitro

We found that strawberry (Fragaria x ananassa) extract has an IgE production suppressive activity and its oral administration improved skin manifestation in atopic dermatitis model mice. In present study, we identified an active substance using the IgE-producing human myeloma cell line U266. Gel filtration experiment indicated that the IgE suppressor was more than 6 kDa in molecular size. In addition, its pectinase treatment inhibited the activity, suggesting that the active substance in strawberry extract is pectin. Among solutions of water-(WP), hexametaphosphate-(HXP), acid-(HP) and alkali soluble pectin (OHP) extracted from strawberry, only OHP suppressed IgE production, and their suppressive activity was cancelled by pectinase treatment. In addition, OHP extracted from apple also inhibited IgE production. Furthermore, OHP also suppressed IgE production and did not affect IgG and IgM production in human peripheral blood mononuclear cells in an in vitro immunization condition. From these results, we concluded that OHP was an IgE suppressor in strawberry extract.

Dehydrocostus lactone, a sesquiterpene from Saussurea lappa Clarke, suppresses allergic airway inflammation by binding to dimerized translationally controlled tumor protein

BACKGROUND

We previously reported that the biologically active form of histamine releasing factor (HRF) is dimerized translationally controlled tumor protein (dTCTP) which is involved in a number of allergic diseases.

HYPOTHESIS/PURPOSE

Hoping that agents that modulate dTCTP may provide new therapeutic targets to allergic inflammatory diseases, we screened a library of natural products for substances that inhibit dTCTP. One such inhibitor we found was dehydrocostus lactone (DCL), a natural sesquiterpene present in rhizome of Saussurea lappa Clarke, the subject of this study.

METHODS

We evaluated the therapeutic efficacy of DCL in a mouse model of ovalbumin (OVA)-induced allergic airway inflammation, employing the ELISA system using BEAS-2B cells and splenocytes, and confirmed that DCL interacts with dTCTP using SPR assay.

RESULTS

DCL inhibited dTCTP-induced secretion of IL-8 in BEAS-2B cells. From kinetic analysis of dTCTP and DCL, we found that K_D value was 5.33 ± 0.03 μM between dTCTP and DCL. DCL also significantly reduced inflammatory lung eosinophilia, type 2 cytokines in BALF, as well as OVA specific IgE and mucus production in a mouse model of ovalbumin induced allergy. Moreover, DCL suppressed NF-κB activation.

CONCLUSION

DCL's therapeutic potential in allergic airway inflammation is based on its anti-inflammatory activity of suppressing the function of dTCTP.

Combined efficacy of oseltamivir, isoprinosine and ellagic acid in influenza A(H3N2)-infected mice

Influenza pathogenesis comprises a complex cascade of impaired cellular processes resulting from the viral replication and exaggerated immune response accompanied by reactive oxygen species (ROS) burst and oxidative stress, destructing membranous structures and tissues. By classical virological and biochemical methods we compared and evaluated the therapeutic effects of 2.5mg/kg/day of the antiviral drug - oseltamivir (OS), 500mg/kg/day of the immune modulator - isoprinosine (IP) and 500mg/kg/day of the antioxidant agent ellagic acid (EA) with a focus on their combined activities in influenza H3N2 virus-infected mice. The survival, lung pathology and titers, as well as the oxidative stress biomarker thiobarbituric acid reactive substances (TBARS) in the lungs, liver and blood plasma, correlated to the activities of the antioxidant enzymes superoxide dismutase (SOD) and glutathione reductase (GR) were assessed. We found that the viral inhibitor applied together with the immune modulator and the antioxidant exhibited strong therapeutic effects on the survival of the influenza-challenged mice. That effect was mostly pronounced for the triple combination - protection index (PI) of 75.2%, mean survival time (MST) extended by 5.8 days compared to the PBS control and significant reduction of the lung titers by 1.38 Δlg; 2.3 scores lower lung pathology and 8 times reduction of the accumulated TBARS in the lungs and liver on the 5^-th day p.i. The enzymatic assays revealed that this combination demonstrated very good protection against the damaging superoxide radicals (83% efficiency of SOD, in comparison to healthy controls 100%). The double combinations of OS with IP and EA also showed protective effects according to the virological analysis - PI of 53.1% and 54.5%. Ten times higher GR activity was observed when the combination EA+OS and monotherapy of EA were applied (96% in comparison to healthy controls 100%). The best antioxidant effect in blood plasma was observed in the EA+IP group - 4 times reduction in the TBARS-content compared to infected controls but it did not have any efficacy on the survival and lung injury.

Asiaticoside Mitigates the Allergic Inflammation by Abrogating the Degranulation of Mast Cells

The effects of asiaticoside (AS) on allergic responses mediated by mast cells were investigated. AS showed no obvious cytotoxicity on RPMCs (rat peritoneal mast cells). AS reduced the intracellular calcium in RPMCs and deprived the histamine release and degranulation. AS also decreased the generation of antigen-induced tumor necrosis factor α, interleukin (IL)-4, IL-8, and IL-1β in RBL-2H3 cells sensitized by IgE. The suppression of AS on pro-inflammatory cytokines was related with the activation of the intracellular FcεRI and the inhibition of the nuclear factor-κB signaling pathway. In addition, AS disabled the phosphorylation of antigen-induced Syk, Lyn, Gab2, and PLCγ1, thus suppressing the downstream Akt phosphorylation and MAPKs pathways. It also increased HO-1 and Nrf2 expression time dependently. In summary, we demonstrate that AS suppresses the allergic inflammation mediated by mast cells and this effect might be mediated by FcεRI-dependent signaling pathways.

Assessing the effect of 5-hydroxymethylfurfural on selected components of immune responses in mice immunised with ovalbumin

BACKGROUND

5-Hydroxymethylfurfural (5-HMF) is one of the most important products of the Maillard reaction. In recent years, many profitable biological effects of this compound have been demonstrated. This study sought to elucidate the anti-allergic effect of 5-HMF by investigating some selected components of the immune response in BALB/c mice immunised with ovalbumin (OVA).

RESULTS

Immunised animals had an increased level of serum total and OVA-specific antibodies when compared to the control (P < 0.01).We found that the OVA-induced increase in serum IgE and OVA-specific IgE were significantly suppressed in the groups treated with 5-HMF (P < 0.05). Moreover, interleukin-4 (IL-4) and interferon gamma (IFN-γ) were significantly reduced in a dose-independent manner when compared to the sensitised group (P < 0.05).

CONCLUSION

5-HMF inhibited the up-regulation of total and OVA-specific IgE through the suppression of the Th2-type immune response in immunised BALB/c mice. 5-HMF could therefore be a novel therapeutic approach for the prevention of IgE-mediated allergic diseases. © 2017 Society of Chemical Industry.

Mandevilla longiflora (Desf.) Pichon improves airway inflammation in a murine model of allergic asthma

ETHNOPHARMACOLOGICAL RELEVANCE

Mandevilla longiflora, popularly known as "velame" in central Brazil, is a subshrub widely distributed in South America. Its xylopodium is used in the form of a decoction or infusion to treat inflammation and other ailments.

AIM OF THE STUDY

This study aimed to evaluate the anti-inflammatory potential of M. longiflora in an in vivo model of ovalbumin-induced immediate hypersensitivity, identifying its effects on leukocyte infiltration, IgE and LTB₄ levels, and Th2 cytokine production. In addition, HPLC fingerprint of the extract was performed.

MATERIAL AND METHODS

The hydroethanolic extract 70% of M. longiflora (HEMI) was obtained by maceration of the plant xylopodium. Swiss mice were sensitized by i.p. injection OVA-aluminium hydroxide on days 1 and 10. Nine days after the last sensitisation animals were challenged for 6 consecutive days with OVA solution for 20min daily in a closed chamber under continuous flow of aerosol. The animals were treated with HEMl (20, 50 and 200mg/kg p.o.), 2 times per day, and euthanized 24h later. Animals treated with vehicle (2% Tween-20) or dexamethasone were used as negative and positive controls, respectively. The recruitment of inflammatory cells into the pulmonary cavity was evaluated by counting cells present in broncho-alveolar lavage fluid (BALF). Lung tissue was also collected for histopathology and infiltration analysis. Quantification of IL-4, IL-5 and IL-13 from the BALF, and IgE, and LTB₄ from plasma, were conducted by immunoassay.

RESULTS AND CONCLUSIONS

The HEMl attenuated leukocyte migration into the airways, which was evidenced by a decrease in eosinophils, neutrophils and mononuclear cells, both in BALF quantification and by histopathological analysis, as well as decreasing the concentrations of IL-4, IL-5, IL-13, IgE and LTB₄. All of these events are typical of air-mucosa inflammatory disease. These findings scientifically evidence for the first time the ethnopharmacological use of M. longiflora to treat chronic inflammatory events, such as asthma, and suggest a potential therapeutic use or complementary therapy for this plant extract.

Beneficial effects of ellagic acid against animal models of scopolamine- and diazepam-induced cognitive impairments

Context In a previous study, it has been shown that ellagic acid (EA), a polyphenolic compound found in pomegranate and different berries, prevents cognitive and hippocampal long-term potentiation (LTP) impairments induced by traumatic brain injury in rats through antioxidant and anti-inflammatory mechanisms. Objective The present study was conducted to assess the potential of EA as a memory enhancer. Materials and methods The elevated plus maze (EPM) and passive avoidance (PA) paradigm were used to evaluate learning and memory parameters. Three doses (10, 30 and 100 mg/kg, i.p.) of EA were administered to animals. Memory impairment was induced by scopolamine treatment (0.4 mg/kg, i.p.) and/or diazepam (1 mg/kg, i.p.). Acquisition trials were carried out 30 min after scopolamine treatment and retention trials were performed for 5 min 24 h after the acquisition trials. Results EA at doses 30 and 100 mg/kg significantly reversed the amnesia induced by scopolamine (0.4 mg/kg, i.p.) in the EPM and PA tests in mice. Also, EA at doses 30 and 100 mg/kg significantly antagonized the amnesia induced by diazepam (1 mg/kg, i.p.) in EPM test in rats. Moreover, chronic administration of EA at dose 30 mg/kg ameliorated the memory deficit induced by diazepam (1 mg/kg, i.p.) in rats. Discussion and conclusion This study demonstrates that ellagic acid is effective in preventing scopolamine- and diazepam-induced cognitive impairments without altering the animals' locomotion. This suggests the potential of EA application as a useful memory restorative agent in the treatment of dementia seen in elderly persons.

Comparative study on the antioxidant capacities of synthetic influenza inhibitors and ellagic acid in model systems

This study compares the antioxidant capacities in vitro of several synthetic and natural compounds applied and researched for influenza treatment - oseltamivir, isoprinosine, ellagic acid, vitamin E and vitamin C. Three chemical systems are utilized for the generation of reactive oxygen species (ROS) at pH 7.4 and pH 8.5: (1) Fenton's (Fe²⁺+H₂O₂) for OH and -OH species (2) H₂O₂ (3) NADH-phenazinemethosulfat, for superoxide radicals (O₂^-). The kinetics was evaluated by lucigenin-enhanced chemiluminescence. The calculated constants of inhibition k₇ describe the antioxidant capacity at the moment of oxidative burst. Their values do not necessarily correspond to the calculated total antioxidant activity. The obtained results revealed that the synthetic anti-influenza drugs (oseltamivir and isoprinosine) as well as ellagic acid possess pronounced scavenging properties mostly against superoxide radicals, comparable and higher than that of traditional natural antioxidants. Quantitative analysis of the antioxidant effects of the examined synthetic substances was performed. The results compared the corresponding effect of the average physiological concentrations and the applied therapeutic antioxidant dose. With these experiments we registered new aspects of their therapeutic activities, due to antioxidant properties against hydroxyl, superoxide radicals and H₂O₂ oxidation.

Cornuside inhibits mast cell-mediated allergic response by down-regulating MAPK and NF-κB signaling pathways

AIMS

The present study is to investigate the effect of cornuside on mast cell-mediated allergic response, as well as its possible mechanisms of action.

METHODS

To test the anti-allergic effects of cornuside in vivo, local extravasation was induced by local injection of anti-dinitrophenyl immunoglobulin E (IgE) followed by intravenous antigenic challenge in passive cutaneous anaphylaxis model rats. Mast cell viability was determined using MTT assay. Histamine content from rat peritoneal mast cells was measured by the radioenzymatic method. To investigate the mechanisms by which cornuside affects the reduction of histamine release, the levels of calcium uptake were measured. To examine whether cornuside affects the expression of pro-inflammatory cytokines, Western blotting and ELISA were carried out.

RESULTS

Oral administration of cornuside inhibited passive cutaneous anaphylaxis in rats. Presence of cornuside attenuated IgE-induced histamine release from rat peritoneal mast cells. The inhibitory effect of cornuside on histamine release was mediated by the modulation of intracellular calcium. In addition, cornuside decreased phorbol 12-myristate 13-acetate (PMA) and calcium ionophore A23187-stimulated production and secretion of pro-inflammatory cytokines such as TNF-α and IL-6 in human mast cells. The inhibitory effect of cornuside on pro-inflammatory cytokines was dependent on nuclear factor-κB and p38 mitogen-activated protein kinase.

CONCLUSIONS

The present study provides evidence that cornuside inhibits mast cell-derived inflammatory allergic reactions by blocking histamine release and pro-inflammatory cytokine expression. Furthermore, in vivo and in vitro anti-allergic effects of cornuside suggest a possible therapeutic application of this agent in inflammatory allergic diseases.

Mast cell stabilisers

Mast cells play a critical role in type 1 hypersensitivity reactions. Indeed, mast cell mediators are implicated in many different conditions including allergic rhinitis, conjunctivitis, asthma, psoriasis, mastocytosis and the progression of many different cancers. Thus, there is intense interest in the development of agents which prevent mast cell mediator release or which inhibit the actions of such mediators once released into the environment of the cell. Much progress into the design of new agents has been made since the initial discovery of the mast cell stabilising properties of khellin from Ammi visnaga and the clinical approval of cromolyn sodium. This review critically examines the progress that has been made in the intervening years from the design of new agents that target a specific signalling event in the mast cell degranulation pathway to those agents which have been developed where the precise mechanism of action remains elusive. Particular emphasis is also placed on clinically used drugs for other indications that stabilise mast cells and how this additional action may be harnessed for their clinical use in disease processes where mast cells are implicated.

Inhibition of allergic airway inflammation through the blockage of NF-κB activation by ellagic acid in an ovalbumin-induced mouse asthma model

Allergic asthma is a complex inflammatory disease characterized by airway hyperresponsiveness, eosinophilic inflammation and the hypersecretion of mucus by goblet cells. Ellagic acid (EA), a natural polyphenolic compound present as ellagitannins in fruits and fruit juices, has been reported to show potent anti-inflammatory properties in various diseases. We aimed to investigate the effects of EA in an ovalbumin (OVA)-induced mouse asthma model and to explore its potential mechanism of action. Our results showed that EA resulted in a significant reduction in lung eosinophilia, increased Th2 cytokines in bronchoalveolar lavage fluid and increased OVA-induced specific IgE in serum samples. Moreover, histological examination showed that EA markedly inhibited lung eosinophilic inflammation and goblet cell hyperplasia. In addition, EA attenuated the development of airway hyperresponsiveness and blocked NF-κB activation. These results demonstrate that EA shows obvious anti-inflammatory effects in OVA-induced asthma in a mouse model, possibly through inhibiting NF-κB activation. Therefore it may be a potential therapeutic agent for the treatment of allergic asthma.

Twenty-first century mast cell stabilizers

Mast cell stabilizing drugs inhibit the release of allergic mediators from mast cells and are used clinically to prevent allergic reactions to common allergens. Despite the relative success of the most commonly prescribed mast cell stabilizer, disodium cromoglycate, in use for the preventative treatment of bronchial asthma, allergic conjunctivitis and vernal keratoconjunctivitis, there still remains an urgent need to design new substances that are less expensive and require less frequent dosing schedules. In this regard, recent developments towards the discovery of the next generation of mast cell stabilizing drugs has included studies on substances isolated from natural sources, biological, newly synthesized compounds and drugs licensed for other indications. The diversity of natural products evaluated range from simple phenols, alkaloids, terpenes to simple amino acids. While in some cases their precise mode of action remains unknown it has nevertheless sparked interest in the development of synthetic derivatives with improved pharmacological properties. Within the purely synthetic class of inhibitors, particular attention has been devoted to the inhibition of important signalling molecules including spleen TK and JAK3. The statin class of cholesterol-lowering drugs as well as nilotinib, a TK inhibitor, are just some examples of clinically used drugs that have been evaluated for their anti-allergic properties. Here, we examine each approach under investigation, summarize the test data generated and offer suggestions for further preclinical evaluation before their therapeutic potential can be realized.

The multicomponent medication lymphomyosot improves the outcome of experimental lymphedema

BACKGROUND

Secondary lymphedema is a life-long disease of painful tissue swelling that often follows axillary lymph node dissection to treat breast cancer. It is hypothesized that poor lymphatic regeneration across the obstructive scar tissue during the wound healing process may predispose the tissue to swell at a later date. Treatment for lymphedema remains suboptimal and is in most cases palliative. The purpose of this study was to evaluate the ability of Lymphomyosot to treat tissue swelling and promote lymphangiogenesis in experimental models of murine lymphedema.

METHODS

Experimental models of mouse lymphedema were injected with varied amounts of Lymphomyosot and saline as control. Measurements of tail swelling and wound closure were taken and compared amongst the groups. Three separate groups of mice were analyzed for lymphatic capillary migration, lymphatic vessel regeneration, and macrophage recruitment.

RESULTS

Lymphomyosot significantly reduced swelling and increased the rate of surgical wound closure. Lymphomyosot did not increase the migration of lymph capillaries in a mouse tail skin regeneration model or regeneration of lymph vessels following murine axillary lymph node dissection.

CONCLUSIONS

Lymphomyosot may act through inflammatory and wound repair pathways to reduce experimental lymphedema. Its ability to regulate inflammation as well as assist in tissue repair and extracellular formation may allow for the production of a scar-free matrix bridge through which migrating cells and accumulated interstitial fluid can freely spread.

Anti-inflammatory effects of ellagic acid on acute lung injury induced by acid in mice

Acute lung injury (ALI) is characterized by alveolar edema and uncontrolled neutrophil migration to the lung, and no specific therapy is still available. Ellagic acid, a compound present in several fruits and medicinal plants, has shown anti-inflammatory activity in several experimental disease models. We used the nonlethal acid aspiration model of ALI in mice to determine whether preventive or therapeutic administration of ellagic acid (10 mg/kg; oral route) could interfere with the development or establishment of ALI inflammation. Dexamethasone (1 mg/kg; subcutaneous route) was used as a positive control. In both preventive and therapeutic treatments, ellagic acid reduced the vascular permeability changes and neutrophil recruitment to the bronchoalveolar lavage fluid (BALF) and to lung compared to the vehicle. In addition, the ellagic acid accelerated the resolution for lung neutrophilia. Moreover, ellagic acid reduced the COX-2-induced exacerbation of inflammation. These results were similar to the dexamethasone. However, while the anti-inflammatory effects of dexamethasone treatment were due to the reduced activation of NF-κB and AP-1, the ellagic acid treatment led to reduced BALF levels of IL-6 and increased levels of IL-10. In addition, dexamethasone treatment reduced IL-1β. Together, these findings identify ellagic acid as a potential therapeutic agent for ALI-associated inflammation.

Pomegranate: a fruit that ameliorates metabolic syndrome

Pomegranate is an ancient fruit that is still part of the diet in the Mediterranean area, the Middle East, and India. Health-promoting effects have long been attributed to this fruit. Modern research corroborates the use of pomegranate as a folk remedy for diabetes and metabolic syndrome, and is responsible for a new evaluation of nutritional and pharmaceutical aspects of pomegranate in the general public. In the last decade, industry and agricultural production have been adapted to meet higher market demands for pomegranate. In vivo and in vitro studies have demonstrated that pomegranate exerts hypoglycaemic effects, including increased insulin sensitivity, inhibition of α-glucosidase, and impact on glucose transporter type 4 function, but is also responsible for a reduction of total cholesterol, and the improvement of blood lipid profiles, as well as anti-inflammatory effects through the modulation of peroxisome proliferator-activated receptor pathways. These effects may also explain how pomegranate-derived compounds function in the amelioration of adverse health effects caused by metabolic syndrome. Pomegranate contains polyphenols such as ellagitannins and anthocyanins, as well as phenolic acids, fatty acids and a variety of volatile compounds. Ellagitannins are some of the most prevalent compounds present in pomegranate, and may be responsible for certain benevolent characteristics associated with pomegranate. A brief overview of rising health problems due to obesity will be provided, followed by characterisation of the biological activity, bioavailability, and safety of pomegranate and pomegranate-derived compounds. Although the fruit is consumed in many countries, epidemiological and clinical studies are unavailable. Additional research is necessary to corroborate the promise of current in vivo and in vitro findings.

Current nutraceuticals in the management of osteoarthritis: a review

Osteoarthritis (OA) is a progressive degenerative joint disease that has a major impact on joint function and quality of life. Nutraceuticals and dietary supplements derived from herbs have long been used in traditional medicine and there is considerable evidence that nutraceuticals may play an important role in inflammation and joint destruction in OA. We review the biological effects of some medicinal fruits and herbs - pomegranate, green tea, cat's claw, devil's claw, ginger, Indian olibaum, turmeric and ananas - in an attempt to understand the pivotal molecular targets involved in inflammation and the joint destruction process and to summarize their toxicities and efficacy for OA management. So far there is insufficient reliable evidence on the effectiveness of ginger, turmeric and ananas. Pomegranate and green tea only have preclinical evidence of efficacy due to the lack of clinical data. In vivo and clinical studies are required to understand their targets and efficacy in OA. Limited in vitro and in vivo evidence is available for cat's claw and Indian olibaum. More extensive studies are required before long-term controlled trials of whole cat's claw and Indian olibaum extracts, or isolated active compounds, are carried out in patients with OA to determine their long-term efficacy and safety. Devil's claw has not been rigorously tested to determine its antiarthritic potential in in vitro and in vivo models. There is strong clinical evidence of the effectiveness of devil's claw in pain reduction. However, high-quality clinical trials are needed to determine its effectiveness. No serious side effects have been reported for any fruits and herbs. Overall, these studies identify and support the use of nutraceuticals to provide symptomatic relief to patients with OA and to be used as adjunct therapy for OA management. More high-quality trials are needed to provide definitive answers to questions related to their efficacy and safety for OA prevention and/or treatment.

Antinociceptive effect of Lafoensia pacari A. St.-Hil. independent of anti-inflammatory activity of ellagic acid

This study was performed to determine the antinociceptive and anti-inflammatory activities of ethanolic extract of Lafoensia pacari A. St.-Hil. (PEtExt) stem bark and its fractions using various animal models such as acetic acid-induced abdominal writhing, formalin-induced pain and croton oil-induced ear edema tests. The PEtExt inhibited the acetic acid-induced abdominal writhing, reduced the pain reaction time on both phases of the formalin test and decreased the edema in a dose-dependent manner. Pre-treatment with naloxone did not reverse the antinociceptive effect. Only the ethyl acetate fraction showed antinociceptive and anti-inflammatory effects. Our results also showed that this extract contains compounds with analgesic action independent of anti-inflammatory activity.

The activity of medicinal plants and secondary metabolites on eosinophilic inflammation

Eosinophils are leukocytes that are present in several body compartments and in the blood at relatively low numbers under normal conditions. However, an increase in the number of eosinophils, in the blood or in the tissues, is observed in allergic or parasitic disorders. Although some progress has been made in understanding the development of eosinophil-mediated inflammation in allergic and parasitic diseases, the discovery of new compounds to control eosinophilia has lagged behind other advances. Plant-derived secondary metabolites are the basis for many drugs currently used to treat pathologic conditions, including eosinophilic diseases. Several studies, including our own, have demonstrated that plant extracts and secondary metabolites can reduce eosinophilia and eosinophil recruitment in different experimental animal models. In this review, we summarize these studies and describe the anti-eosinophilic activity of various plant extracts, such as Ginkgo biloba, Allium cepa, and Lafoensia pacari, as well as those of secondary metabolites (compounds isolated from plant extracts), such as quercetin and ellagic acid. In addition, we highlight the medical potential of these plant-derived compounds for treating eosinophil-mediated inflammation, such as asthma and allergy.