Polyphenol extract from evening primrose pomace alleviates experimental colitis after intracolonic and oral administration in mice

A systematic review on the role of gut microbiome in inflammatory bowel disease: Spotlight on virome and plant metabolites

Inflammatory bowel diseases (IBD), including ulcerative colitis and Crohn's disease, arise from various factors such as dietary, genetic, immunological, and microbiological influences. The gut microbiota plays a crucial role in the development and treatment of IBD, though the exact mechanisms remain uncertain. Current research has yet to definitively establish the beneficial effects of the microbiome on IBD. Bacteria and viruses (both prokaryotic and eukaryotic) are key components of the microbiome uniquely related to IBD. Numerous studies suggest that dysbiosis of the microbiota, including bacteria, viruses, and bacteriophages, contributes to IBD pathogenesis. Conversely, some research indicates that bacteria and bacteriophages may positively impact IBD outcomes. Additionally, plant metabolites play a crucial role in alleviating IBD due to their anti-inflammatory and microbiome-modulating properties. This systematic review discusses the role of the microbiome in IBD pathogenesis and evaluates the potential connection between plant metabolites and the microbiome in the context of IBD pathophysiology.

Efficacy of combination of N-acetylcysteine and primrose in spinal cord injury; an experimental study

Introduction

Spinal cord trauma represents a major cause of emergency department admissions, with high morbidity and mortality rates. It requires early and urgent treatment. This experimental study assessed the effectiveness of a combination of primrose and N-acetylcysteine (NAC) in managing spinal cord injury (SCI).

Methods

We divided 46 adult male Wistar albino rats (6-8 months old, weighing 300-350 g) into five groups. Group 1 (n = 10) received only primrose; group 2 (n = 10) received only NAC; group 3 (n = 10) received a combination of NAC and primrose; group 4 (n = 10) received no intervention (first control group); group 5 (n = 10) underwent laminectomy only (second control group). Intergroup neurological and motor function were evaluated on days 1, 7, and 14. Oxidative biochemical markers, such as superoxide dismutase (SOD), glutathione peroxidase (GPX), and malondialdehyde (MDA), were measured.

Results

Significant differences were recorded in the GPX, SOD, and MDA values of groups 1, 2, 3, and 4 (p < 0.001, p = 0.005, and p = 0.097, respectively). Groupwise comparisons were conducted to identify the clinical significance of these markers. GPX and SOD levels were significantly higher in group 1 than in group 2; MDA levels were lower in group 1. GPX and SOD levels were significantly higher than in group 3 than in group 1; MDA levels were lower in group 3. Compared with group 5, group 1 demonstrated significantly higher GPX and SOD levels and lower MDA levels. Results in group 2 were similar to results in group 5. In group 3, GPX and SOD levels were significantly higher than in groups 2 and 5; MDA levels were significantly lower. Comparisons according to inclined plane angle level and motor function values revealed significant results on day 14, in favor of group 3 rats that had received the combined treatment.

Conclusion

The combined administration of NAC and primrose for traumatic SCI was more effective than either treatment alone in terms of improving biochemical and neurological functions. These findings suggest that the combination of NAC and primrose can serve as an effective treatment option for traumatic SCI.

Oxidative Stability and Protective Effect of the Mixture between Helianthus annuus L. and Oenothera biennis L. Oils on 3D Tissue Models of Skin Irritation and Phototoxicity

The present study was aimed to evaluate the oxidative stability as well as to assess the protective effect of the mixture of Helianthus annuus L. (HAO) and Oenothera biennis L. (OBO) oils on 3D tissue models of skin irritation and phototoxicity. The following methods were used: GS analysis (fatty acids composition), thiobarbituric acid-reactive substances assay (TBA) (lipid oxidation degree of tested samples), 3D EpiDerm models (skin irritation and phototoxicity). For HAO the detected saturated fatty acids (SFA) were palmitic acid (7.179%), stearic acid (3.586%), eicosanoic (0.138%) and docosanoic acid (0.548%) The monounsaturated acids (MUFA) were palmitoleic acid (0.158%) and oleic acid (28.249%) and the polyunsaturated acids (PUFA) were linoleic acid (59.941%) and linolenic acid (0.208%). For OBO the detected SFA were myristic acid (0.325%), pentadecylic acid (0.281%), palmitic (7.2%), stearic (2.88%), and arachidic acid (0.275%). Regarding MUFA, even a lower proportion (8.196%) was observed, predominantly being oleic acid, cis form (7.175%), oleic (n10) (0.558%) and 11-eicosenoic (0.210%) acids. The higher content was found for PUFA (82.247%), the most significant proportions being linoleic acid (72.093%), arachidonic acid (9.812%) and linolenic (0.233%). Obtained data indicate a good oxidative stability and biocompatibility of the mixture on the 3D EpiDerm models with no irritant and no phototoxic effects. Oenothera biennis L. oil may be an excellent natural choice in order to delay or prevent oxidative damage of Helianthus annuus L. oil.

Natural compounds as safe therapeutic options for ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory bowel disease of unknown etiology. Several conventional treatments for UC such as corticosteroids, immunosuppressive agents, tumor necrosis factor antagonist, integrin blockers, and interleukin antagonist, and salicylates are available but are associated with the various limitations and side-effects. None of the above treatments helps to achieve the ultimate goal of the therapy, i.e., maintenance of remission in the long-term. Natural remedies for the treatment of UC show comparatively less side effects as compared to conventional approaches, and affordable. The current review presents details on the role of herbal drugs in the treatment and cure of UC. Google, PubMed, Web of Science, and Scopus portals have been searched for potentially relevant literature to get the latest developments and updated information related to use of natural drugs in the treatment of UC. Natural products have been used over centuries to treat UC. Some of the essential herbal constituents exhibiting antiulcerogenic activity include gymnemic acid (Gymnema sylvestre), shagoal (Zingiber officinale), catechin (Camellia sinensis), curcumin (Curcuma longa), arctigenin (Arctium lappa), and boswellic acid (Boswellia serrata). Although many plant-derived products have been recommended for UC, further research to understand the exact molecular mechanism is still warranted to establish their usefulness clinically.

The potential and outgoing trends in traditional, phytochemical, economical, and ethnopharmacological importance of family Onagraceae: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

The Onagraceae is a widely distributed family of flowering plants comprises about 17 genera and more than 650 species of herbs, shrubs, and trees. Onagraceae also common as willowherb family or evening primrose family is divided into two subfamilies; Ludwigioideae (mainly genus; Ludwigia) and Onagroideae. Family Onagraceae is characterized by its numerous traditional uses as treatment of hormonal imbalances, urinary system ailments, prostate health maintenance, and antimicrobial effects.

AIM OF THE STUDY

This review aims to introduce a holistic overview on the phytochemical composition, economical importance and ethnopharmacological value of different species of family Onagraceae.

MATERIALS AND METHODS

Literature review was performed using different data bases such as PubMed, Web of Science, Google Scholar and Reaxys searching for articles focused on phytochemical composition, bioactivity and ethnopharmacological history of Onagraceae species.

RESULTS

Different species of Onagraceae were reported to have a great variety of phytochemicals including flavonoids, tannins, phenolic acids, triterpenoids, saponins, and volatile/fixed oils. Onagraceae exhibited several health benefits and pharmacological activities including anti-inflammatory, antiarthritic and analgesic, antioxidant, cytotoxic, antidiabetic, and antimicrobial.

CONCLUSIONS

Family Onagraceae is an extremely important family with diverse phytochemical composition which enriches their pharmacological importance and hence it's commercial and economical value.

Characterization of the Synergistic Effect between Ligands of Opioid and Free Fatty Acid Receptors in the Mouse Model of Colitis

Background: Recent studies suggest that lipids, including free fatty acids (FFAs), are necessary for proper μ opioid receptor (MOR) binding and that activation of opioid receptors (ORs) improves intestinal inflammation. The objective of the study was to investigate a possible interaction between the ORs and FFA receptors (FFARs) ligands in the colitis. Methods: The potential synergistic effect of ORs and FFARs ligands was evaluated using mouse model of acute colitis induced by dextran sulfate sodium (DSS, 4%). Compounds were injected intraperitoneally (i.p.) once or twice daily at the doses of 0.01 or 0.02 mg/kg body weight (BW) (DAMGO—an MOR agonist), 0.3 mg/kg BW (DPDPE—a δ OR (DOR) agonist) and 1 mg/kg BW (naloxone—a non-selective OR antagonist, GLPG 0974—a FFAR2 antagonist, GSK 137647—a FFAR4 agonist and AH 7614—a FFAR4 antagonist) for 4 days. Results: Myeloperoxidase (MPO) activity was significantly decreased after DAMGO (0.02 mg/kg BW) and GSK 137647 (1 mg/kg BW) administration and co-administration as compared to DSS group. Conclusions: Treatment with ligands of ORs and FFARs may affect the immune cells in the inflammation; however, no significant influence on the severity of colitis and no synergistic effect were observed.

Phytochemicals in Malignant Pleural Mesothelioma Treatment-Review on the Current Trends of Therapies

Malignant pleural mesothelioma (MPM) is a rare but highly aggressive tumor of pleura arising in response to asbestos fibers exposure. MPM is frequently diagnosed in the advanced stage of the disease and causes poor prognostic outcomes. From the clinical perspective, MPM is resistant to conventional treatment, thus challenging the therapeutic options. There is still demand for improvement and sensitization of MPM cells to therapy in light of intensive clinical studies on chemotherapeutic drugs, including immuno-modulatory and targeted therapies. One way is looking for natural sources, whole plants, and extracts whose ingredients, especially polyphenols, have potential anticancer properties. This comprehensive review summarizes the current studies on natural compounds and plant extracts in developing new treatment strategies for MPM.

Antioxidant, Antimicrobial and Antiviral Properties of Herbal Materials

Recently, increasing public concern about hygiene has been driving many studies to investigate antimicrobial and antiviral agents. However, the use of any antimicrobial agents must be limited due to their possible toxic or harmful effects. In recent years, due to previous antibiotics' lesser side effects, the use of herbal materials instead of synthetic or chemical drugs is increasing. Herbal materials are found in medicines. Herbs can be used in the form of plant extracts or as their active components. Furthermore, most of the world's populations used herbal materials due to their strong antimicrobial properties and primary healthcare benefits. For example, herbs are an excellent material to replace nanosilver as an antibiotic and antiviral agent. The use of nanosilver involves an ROS-mediated mechanism that might lead to oxidative stress-related cancer, cytotoxicity, and heart diseases. Oxidative stress further leads to increased ROS production and also delays the cellular processes involved in wound healing. Therefore, existing antibiotic drugs can be replaced with biomaterials such as herbal medicine with high antimicrobial, antiviral, and antioxidant activity. This review paper highlights the antibacterial, antiviral, and radical scavenger (antioxidant) properties of herbal materials. Antimicrobial activity, radical scavenger ability, the potential for antimicrobial, antiviral, and anticancer agents, and efficacy in eliminating bacteria and viruses and scavenging free radicals in herbal materials are discussed in this review. The presented herbal antimicrobial agents in this review include clove, portulaca, tribulus, eryngium, cinnamon, turmeric, ginger, thyme, pennyroyal, mint, fennel, chamomile, burdock, eucalyptus, primrose, lemon balm, mallow, and garlic, which are all summarized.

Polyphenol Extract from Evening Primrose (Oenothera paradoxa) Inhibits Invasion Properties of Human Malignant Pleural Mesothelioma Cells

Extracts from the defatted evening primrose (Oenothera paradoxa Hudziok) seeds are the source of a range of stable polyphenolic compounds, including ellagic acid, gallic acid, and catechin. Our studies evaluate, for the first time, the influence of evening primrose isopropanol extract (EPE) on malignant pleural mesothelioma (MPM) cells. MPM is rarely diagnosed, its high aggressiveness and frequently noted chemoresistance limit its treatment schemes and it is characterized by low prognostic features. Here, we demonstrate that EPE inhibited MPM growth in a dose-dependent manner in cells with increased invasion properties. Moreover, EPE treatment resulted in cell cycle arrest in the G2/M phase and increased apoptosis in invasive MPM cell lines. Additionally, EPE strongly limited invasion and MMP-7 secretion in MPM cancer cells. Our original data provide evidence about the potential anti-invasive effects of EPE in MPM therapy treatment.

Ultraviolet A protective potential of plant extracts and phytochemicals

Chronic exposure to solar radiation is related to an increased incidence of various skin disorders, including premature skin aging and melanoma and non-melanoma skin cancers. Ultraviolet (UV) photons in particular are responsible for skin damage. Solar UV photons mainly belong to UVA wavebands, however UVA radiation has been mostly ignored for a long time. At the cellular level, UVA photons mainly provoke indirect oxidative damage to biomolecules via the massive generation of unstable and highly reactive compounds. Human skin has several effective mechanisms that forestall, repair and eliminate damage caused by solar radiation. Regardless, some damage persists and can accumulate with chronic exposure. Therefore, conscious protection against solar radiation (UVB+UVA) is necessary. Besides traditional types of photoprotection such as sunscreen use, new strategies are being searched for and developed. One very popular protective strategy is the application of phytochemicals as active ingredients of photoprotection preparations instead of synthetic chemicals. Phytochemicals usually possess additional biological activities besides absorbing the energy of photons, and those properties (e.g. antioxidant, anti-inflammatory) magnify the protective potential of phytochemicals and extracts. Therefore, compounds of natural origin are in the interest of researchers as well as developers. In this review, only studies on UVA protection with well-documented experimental conditions are summarized. This article includes 17 well standardized plant extracts (Camellia sinensis (L.) Kuntze, Silybum marianum L. Gaertn., Punica granatum L., Polypodium aureum L., Vaccinium myrtillus L., Lonicera caerulea L., Thymus vulgaris L., Opuntia ficus-indica (L.) Mill., Morinda citrifolia L., Aloe vera (L.) Burm.f., Oenothera paradoxa Hudziok, Galinsoga parviflora Cav., Galinsoga quadriradiata Ruiz et Pavón, Hippophae rhamnoides L., Cola acuminata Schott & Endl., Theobroma cacao L. and Amaranthus cruentus L.) and 26 phytochemicals.

Evening Primrose Oil Ameliorates Hyperleptinemia and Reproductive Hormone Disturbances in Obese Female Rats: Impact on Estrus Cyclicity

Obesity is a public health burden disturbing all body functions and reproductive hormones. As obesity increases among females, there will be a rising challenge to physicians in care from fertility problems. Evening primrose oil (EPR oil) contains essential fatty acids including omega-6 linoleic acid with strong anti-inflammatory activity. Since EPR oil has utility in alleviating dysmenorrhea, this study aimed to ascertain its modulatory effect on systemic inflammation, reproductive hormones and estrus cycle irregularity in female obese rats. Thirty-two female rats were distributed to 4 groups: (i) normal, (ii) dietary obese-control female rats, and (iii and iv) dietary obese female rats treated with EPR oil (5 or 10 g/kg). Rats were examined for estrus regularity by taking vaginal smears daily during the last 2 weeks of the experiment. Serum level of insulin, leptin, adiponectin, and inflammatory cytokines was measured. In addition, serum lipid profile, and liver enzyme activities were estimated. Adipose tissues were taken for histopathologic examination as well as determination of gene expression for leptin, leptin receptors, adiponectin, and visfatin. Obese rats exhibited significant weight gain (90.69 ± 8.9), irregular prolonged estrus cycles (83.33%), increased serum levels of insulin, leptin, prolactin and testosterone and decreased gonadotropin levels. EPR oil exhibited a curative effect on obesity-related irregularity in estrus cycle and ovarian pathology. The underlying molecular mechanism may be related to reduction of systemic inflammation, alleviating insulin resistance and modulation of adipokine expression. EPR oil may be considered as a promising therapeutic intervention against obesity-related female hormonal disturbances and estrus irregularity.

High activity of endogenous opioid system protects against gastric damage development in mouse models of gastric mucosal injury

BACKGROUND

Gastric mucosal injury appears when acid and pepsin production, simultaneously with inadequate mucosal response, overwhelms protective mechanism in stomach. Here we aimed to explore the linkage between gastric lesion formation and endogenous opioid system activity.

METHODS

Two mouse lines bidirectionally selected for high (HA) and low (LA) swim stress-induced analgesia associated with high and low endogenous opioid system activity were used. Gastric mucosal injury was induced by ethanol (EtOH) and chronic mild stress. To investigate the anti-inflammatory effect of the endogenous opioid system macroscopic score, myeloperoxidase (MPO) activity, the expression of inflammatory molecules as well as oxidative stress markers were determined. Moreover, expression of opioid receptors μ (MOR), κ (KOR) and δ (DOR) at mRNA levels were determined in gastric tissue.

RESULTS

High activity of the endogenous opioid system alleviated gastric lesions development in the EtOH-and chronic mild stress-induced mouse gastric mucosal injury models, as demonstrated by decreased macroscopic score in HA line compared to LA. Additionally, antioxidative stress defence mechanisms were positively modulated in both models of gastric mucosal injury. MOR and partially KOR receptors may be responsible for the gastroprotective effect.

CONCLUSION

To our knowledge this is the first study to show that increased activity of the endogenous opioid system prevents from gastric lesion formation by influencing - among others - the anti-inflammatory and anti-oxidant mechanisms in the mice stomach. Hence, we suggest that opioids may play an important role in gastric mucosal injury prevention.

Novel peptide inhibitor of dipeptidyl peptidase IV (Tyr-Pro-D-Ala-NH2) with anti-inflammatory activity in the mouse models of colitis

Protease inhibition has become a new possible approach in the inflammatory bowel disease (IBD) therapy. A serine exopeptidase, dipeptidyl peptidase IV (DPP IV) is responsible for inactivation of incretin hormone, glucagon-like peptide 2 (GLP-2), a potent stimulator of intestinal epithelium regeneration and growth. Recently we showed that the novel peptide analog of endomorphin-2, EMDB-1 (Tyr-Pro-D-ClPhe-Phe-NH₂) is a potent blocker of DPP IV and exhibits an anti-inflammatory activity in vivo. The aim of this study was to design, synthesize and characterize the therapeutic activity and mechanism of action of a series of novel EMDB-1 analogs. The inhibitory potential of all peptides was evaluated using the fluorometric screening assay employing Gly-Pro-Aminomethylcoumarin (AMC) to measure DPP IV activity. Consequently, one compound, namely DI-1 was selected and its therapeutic activity evaluated using mouse models of experimental colitis (induced by TNBS and DSS). Macro- and microscopic score, ulcer score, colonic wall thickness as well as myeloperoxidase activity were measured. We showed that DI-1 blocks DPP IV in vitro (IC₅₀ = 0.76 ± 0.04 nM) and attenuates acute, semichronic and relapsing TNBS- as well as DSS-induced colitis in mice after topical administration. Its anti-inflammatory action is associated with the increase of colonic GLP-2 but not GLP2 receptor or DPP IV expression. Our results validate DPP IV as a pharmacological target for the anti-IBD drugs and its inhibitors, such as DI-1, have the potential to become valuable anti-inflammatory therapeutics.

Highly selective CB2 receptor agonist A836339 has gastroprotective effect on experimentally induced gastric ulcers in mice

Cannabinoid type 2 (CB₂) receptors are distributed in central and peripheral tissues, including immunocytes and the gastrointestinal (GI) tract, suggesting that CB₂ receptor agonists represent potential therapeutics in GI inflammatory states. In this study, we investigated the effect of highly selective CB₂ agonist, A836339, on the development of gastric lesions. We used two models of gastric ulcer (GU) induced by ethanol (EtOH) and diclofenac. To confirm the involvement of CB₂ receptors, a selective CB₂ antagonist, AM630 was used. Clinical parameters for gastroprotection were assessed based on inhibition of the gastric lesion area. To investigate the anti-inflammatory effect of A836339, the expression of TNF-α and IL-1β was assessed. To establish the mechanism of gastroprotective action, catalase (CAT), superoxide dismutase (SOD) activity and H₂O₂ and glutathione (GSH) levels were measured. Moreover, expression of CB₂ and cyclooxygenase-2 (COX-2) was characterized using immunohistochemistry (IHC). A836339 reduced ulcer index in a dose-dependent manner in both EtOH- and diclofenac-induced GU models. This effect was reversed by the CB₂ antagonist AM630. Administration of A836339 reduced TNF-α and IL-1β levels in gastric tissue. Furthermore, A836339 exhibited potent anti-oxidant activity, as demonstrated by reduced H₂O₂ levels and increased CAT and SOD activities. IHC studies revealed a co-localization of CB₂ receptors and COX-2 in the gastric tissue. Activation of CB₂ receptors exhibited gastroprotective effect through enhancement of anti-oxidative pathways in the stomach. Activation of CB₂ receptors may thus become a novel therapeutic approach in the treatment of GU.

Polyunsaturated Fatty Acids and Their Derivatives: Therapeutic Value for Inflammatory, Functional Gastrointestinal Disorders, and Colorectal Cancer

Polyunsaturated fatty acids (PUFAs) are bioactive lipids which modulate inflammation and immunity. They gained recognition in nutritional therapy and are recommended dietary supplements. There is a growing body of evidence suggesting the usefulness of PUFAs in active therapy of various gastrointestinal (GI) diseases. In this review we briefly cover the systematics of PUFAs and their metabolites, and elaborate on their possible use in inflammatory bowel disease (IBD), functional gastrointestinal disorders (FGIDs) with focus on irritable bowel syndrome (IBS), and colorectal cancer (CRC). Each section describes the latest findings from in vitro and in vivo studies, with reports of clinical interventions when available.

Bioactivity of Polyphenols: Preventive and Adjuvant Strategies toward Reducing Inflammatory Bowel Diseases-Promises, Perspectives, and Pitfalls

Inflammatory bowel diseases (IBDs) are characterized by autoimmune and inflammation-related complications of the large intestine (ulcerative colitis) and additional parts of the digestive tract (Crohn's disease). Complications include pain, diarrhoea, chronic inflammation, and cancer. IBD prevalence has increased during the past decades, especially in Westernized countries, being as high as 1%. As prognosis is poor and medication often ineffective or causing side effects, additional preventive/adjuvant strategies are sought. A possible approach is via diets rich in protective constituents. Polyphenols, the most abundant phytochemicals, have been associated with anti-inflammatory, antioxidant, immunomodulatory, and apoptotic properties. Locally reducing oxidative stress, they can further act on cellular targets, altering gene expression related to inflammation, including NF-κB, Nrf-2, Jak/STAT, and MAPKs, suppressing downstream cytokine formation (e.g., IL-8, IL-1β, and TNF-α), and boosting the bodies' own antioxidant status (HO-1, SOD, and GPx). Moreover, they may promote, as prebiotics, healthy microbiota (e.g., Bifidobacteria, Akkermansia), short-chain fatty acid formation, and reduced gut permeability/improved tight junction stability. However, potential adverse effects such as acting as prooxidants, or perturbations of efflux transporters and phase I/II metabolizing enzymes, with increased uptake of undesired xenobiotics, should also be considered. In this review, we summarize current knowledge around preventive and arbitrary actions of polyphenols targeting IBD.

Favorable results from the use of herbal and plant products in inflammatory bowel disease: evidence from experimental animal studies

The use of herbal therapy for inflammatory bowel disease is increasing worldwide. The aim of this study was to review the available literature on the efficacy of herbal therapy in experimental colitis. All relevant studies published in Medline and Embase up to June 2015 have been reviewed. The results of bowel histology and serum parameters have been recorded. A satisfactory number of published experimental studies, and a quite large one of both herbal and plant products tested in different studies have been reported. The results showed that in the majority of the studies, herbal therapy reduced the inflammatory activity of experimental colitis and diminished the levels of many inflammatory indices, including serum cytokines and indices of oxidative stress. The most promising plant and herbal products were tormentil extracts, wormwoodherb, Aloe vera, germinated barley foodstuff, curcumin, Boswellia serrata, Panax notoginseng, Ixeris dentata, green tea, Cordia dichotoma, Plantago lanceolata, Iridoidglycosides, and mastic gum. Herbal therapies exert their therapeutic benefit via various mechanisms, including immune regulation, anti-oxidant activity, inhibition of leukotriene B4 and nuclear factor-κB, and antiplatelet activity. Large, double-blind clinical studies assessing these natural substances should be urgently conducted.

Enhancement of anticancer potential of polyphenols by covalent modifications

As evidenced by a growing number of respective clinical trials, a promising and increasingly valued approach to cancer prevention is chemoprevention which is based on using synthetic, semisynthetic, or natural compounds with the aim of preventing, delaying, arresting, or reversing carcinogenesis. Research carried out in the last two decades indicates that natural polyphenols isolated from plants (as well as their derivatives and synthetic analogs) exhibit pleiotropic actions toward cancer cells and therefore they could be used in both cancer prevention and therapy. This review discusses selected covalent modifications of polyphenols as a means for increasing their anticancer potential in relation to the parent compounds. The modifications include hydroxylation, methylation, acylation, and galloylation, among others. They were demonstrated to enhance cytotoxic, pro-oxidant, antiproliferative, proapoptotic, proautophagic, and antimigratory activities of phenolics toward various cancer cell lines in vitro. Importantly, some derivatives proved to suppress tumor growth and metastasis in animal models more strongly than the parent compounds. Some of the above-mentioned covalent modifications were also shown to increase absorption and tissue distribution of tested phenolic compounds in vivo. Anticancer clinical trials with polyphenol derivatives therefore seem warranted.

Experimental colitis in mice is attenuated by topical administration of chlorogenic acid

Epidemiological data suggest that the consumption of polyphenol-rich foods reduces the incidence of cancer, coronary heart disease, and inflammation. Chlorogenic acid (CGA), an ester of caffeic and quinic acids, is one of the most abundant polyphenol compounds in human diet with proven biological effectiveness both in vitro and in vivo. The aim of the study is to investigate the possible anti-inflammatory effect of CGA in the gastrointestinal (GI) tract and its mechanism of action. We used a well-established model of colitis, induced by intracolonic (i.c.) administration of trinitrobenzenesulfonic acid (TNBS) in mice. The anti-inflammatory effect of CGA in the colon was evaluated based on the clinical and macroscopic and microscopic parameters. To investigate the mechanism of protective action of CGA, myeloperoxidase (MPO), H2O2, and NF-κB levels were assessed in the colon tissue. CGA administered i.c. at the dose of 20 mg/kg (two times daily) protected against TNBS-induced colitis more effectively than the same dose administered orally (p.o.), as evidenced by significantly lower macroscopic and ulcer scores. Furthermore, CGA (20 mg/kg, i.c.) reduced neutrophil infiltration, as demonstrated by decreased MPO activity. Moreover, CGA suppressed activation of NF-κB, as evidenced by lower levels of phospho-NF-κB/NF-κB ratio in the tissue. CGA did not affect the oxidative stress pathways. CGA exhibits anti-inflammatory properties through reduction of neutrophil infiltration and inhibition of NF-κB-dependent pathways. Our results suggest that CGA may have the potential to become a valuable supplement in the treatment of GI diseases.

Oral administration of geraniol ameliorates acute experimental murine colitis by inhibiting pro-inflammatory cytokines and NF-κB signaling

Oral administration of geraniol ameliorates DSS-induced ulcerative colitis in mice.