Aloysia triphylla infusion protects rats against dextran sulfate sodium-induced colonic damage

Anti-inflammatory and anti-hyperalgesic effects induced by an aqueous aged black garlic extract in rodent models of ulcerative colitis and colitis-associated visceral pain

Inflammatory bowel disease (IBD) is a morbid condition characterized by relapsing-remitting inflammation of the colon, accompanied by persistent gut dysmotility and abdominal pain. Different reports demonstrated biological activities of aged black garlic (ABG), including anti-inflammatory and antioxidant effects. We aimed to investigate beneficial effects exerted by ABGE on colon inflammation by using ex vivo and in vivo experimental models. We investigated the anti-inflammatory effects of an ABG water extract (ABGE) on rat colon specimens exposed to E. coli lipopolysaccharide (LPS), a known ex vivo experimental model of ulcerative colitis. We determined gene expression of various biomarkers involved in inflammation, including interleukin (IL)-1β, IL-6, nuclear factor-kB (NF-kB), tumor necrosis factor (TNF)-α. Moreover, we studied the acute effects of ABGE on visceral pain associated with colitis induced by 2,4-di-nitrobenzene sulfonic acid (DNBS) injection in rats. ABGE suppressed LPS-induced gene expression of IL-1β, IL-6, NF-kB, and TNF-α. In addition, the acute administration of ABGE (0.03-1 g kg-1) dose-dependently relieved post-inflammatory visceral pain, with the higher dose (1 g kg-1) able to significantly reduce both the behavioral nociceptive response and the entity of abdominal contraction (assessed by electromyography) in response to colorectal distension after the acute administration in DNBS-treated rats. Present findings showed that ABGE could represent a potential strategy for treatment of colitis-associated inflammatory process and visceral pain. The beneficial effects induced by the extract could be related to the pattern of polyphenolic composition, with particular regard to gallic acid and catechin.

Coriandrum sativum and Aloysia triphylla can Protect the Development of Cancer: An in Vivo Study using Mouse Painting Assay

AIM

The aim of this study is to examine the protective properties of Coriandrum sativum and Aloysia triphylla against the development of skin cancer.

METHODS

The skin cancer balb/c mouse model was utilized in the study. Plant extracts were administered to animals using oral gavage. In addition, skin cancer was induced using 7,12-dimethylbenz( a) anthracene (DMBA).

RESULTS

The study found that A. triphylla extract reduced both tumor incidence (P<0.01) and papilloma frequency (P<0.001) and delayed the onset of tumor development (P<0.001). The A. triphylla extract did not affect tumor size in animals. C. sativum leaf extract reduced the number of tumors per animal, the incidence of tumors, and the frequency of papilloma (P<0.05). In addition, it delayed (P<0.01) the onset of tumors. Treatment of animals with C. sativum seed extract reduced the frequency of papilloma (P<0.05) and delayed the onset of tumors (P<0.05). However, the examined plant extracts did not impact the size of tumors induced by DMBA (P>0.05).

CONCLUSION

The findings of this study revealed that C. sativum and A. triphylla could protect against cancer development as indicated using the animal model of skin painting assay.

Chemical Characterization of Different Extracts from Artemisia annua and Their Antioxidant, Enzyme Inhibitory and Anti-Inflammatory Properties

Artemisia annua L. (Asteraceae Family) is an important plant in Asia that has been used for treating different diseases, including fever due to malaria, wounds, tubercolisis, scabues, pain, convulsions, diabetes, and inflammation. In this study we aimed to evaluate the effects of different polarity extracts (hexane, dichloromethane, ethyl acetate, ethanol, ethanol/water (70 %) and water) from A. annua against the burden of inflammation and oxidative stress occurring in colon tissue exposed to LPS. In parallel, chemical composition, antiradical, and enzyme inhibition effects against α-amylase, α-glucosidase, tyrosinase, and cholinesterases were evaluated. The water extract contained the highest content of the total phenolic with 34.59 mg gallic acid equivalent (GAE)/g extract, while the hexane had the highest content of the total flavonoid (20.06 mg rutin equivalent (RE)/g extract). In antioxidant assays, the polar extracts (ethanol, ethanol/water and water) exhibited stronger radical scavenging and reducing power abilities when compared to non-polar extracts. The hexane extract showed the best AChE, tyrosinase and glucosidase inhibitory effects. All extracts revealed effective anti-inflammatory agents, as demonstrated by the blunting effects on COX-2 and TNFα gene expression. These effects seemed to be not related to the only phenolic content. However, it is worthy of interest to highlight how the higher potency against LPS-induced gene expression was shown by the water extract ; thus suggesting a potential phytotherapy application in the management of clinical symptoms related to inflammatory colon diseases, although future in vivo studies are needed to confirm such in vitro and ex vivo observations.

Screening for Chemical Characterization and Pharmacological Properties of Different Extracts from Nepeta italica

Plants from the Nepeta genus have been proved to possess different pharmacological properties, among which are antimicrobial, antioxidant, anti-inflammatory, analgesic, and cytotoxic effects. Nepeta italica is a medicinal plant traditionally used for its analgesic effects, and in the present study, the phytochemical composition and biological effects of hexane, dichloromethane (DCM), ethyl acetate (EA), ethanol, ethanol-water, and water extracts of the aerial parts were investigated for determining phenolic composition, antioxidant effects, and anti-inflammatory effects in isolated mouse colon specimens exposed to lipopolysaccharide (LPS). Polar extracts were the richest in terms of phenolic compounds, especially rosmarinic acid. In parallel, ethanol, ethanol-water, and water extracts were also the most effective as scavenging/reducing and enzyme inhibition agents, especially towards cholinesterases and α-glucosidase, and in inhibiting the LPS-induced cyclooxygenase-2 (COX-2) and tumor necrosis factor α (TNFα) gene expression in mouse colon. This poses the basis for future in vivo investigations for confirming the protective effects of polar extracts of N. italica against inflammatory bowel diseases.

Toxicological potential of Aloysia gratissima: Insights from chemical analysis and in vitro studies

ETHNOPHARMACOLOGICAL RELEVANCE

Aloysia gratissima leaves are popularly used to treat respiratory, digestive, and nervous system disorders. Several studies have been carried out to determine the biological activity of A. gratissima, such as its antibacterial and anti-edematogenic activities, but despite the beneficial uses of A. gratissima, few studies have examined the toxicological profile of this plant.

AIM OF THE STUDY

This study aimed to determine the chemical composition, cytotoxic, genotoxic, mutagenic potential, and antioxidant activity of an aqueous extract of A. gratissima leaves (AG-AEL).

MATERIAL AND METHODS

The phytochemical constitution of AG-AEL was assessed by colorimetric analyses and High-performance liquid chromatography (HPLC). The inorganic elements were detected by Particle-Induced X-ray Emission (PIXE). The antioxidant, cytotoxicity, genotoxic, and mutagenic activities were evaluated in vitro by Di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH), Sulforhodamine B (SRB) assay, comet assay, and Salmonella/microsome assays.

RESULTS

AG-AEL indicated the presence of terpenoids, flavonoids, and phenolic acids. HPLC detected rutin at 2.41 ± 0.33 mg/100 mg. PIXE analysis indicated the presence of Mg, Si, P, S, K, Ca, Mn, and Zn. The 50% inhibitory concentration was 84.17 ± 3.17 μg/mL in the DPPH assay. Genotoxic effects were observed using the Comet assay in neuroblastoma (SH-SY5Y) cells and mutations were observed in TA102 and TA97a strains. The extract showed cytotoxic activities against ovarian (OVCAR-3), glioblastoma (U87MG), and colon (HT-29) cancer cell lines.

CONCLUSIONS

In conclusion, AG-AEL increased DNA damage, induced frameshift, and oxidative mutations, and showed cytotoxic activities against different cancer cells. The in vitro toxicological effects observed suggest that this plant preparation should be used with caution, despite its pharmacological potential.

Anti-Inflammatory and Antioxidant Effects Induced by Allium sativum L. Extracts on an Ex Vivo Experimental Model of Ulcerative Colitis

Inflammatory bowel diseases (IBDs) are chronic and multifactorial inflammatory conditions of the colonic mucosa (ulcerative colitis), characterized by increased and unbalanced immune response to external stimuli. Garlic and its bioactive constituents were reported to exert various biological effects, including anti-inflammatory, antioxidant and immunomodulatory activities. We aimed to evaluate the protective effects of a hydroalcoholic (GHE) and a water (GWE) extract from a Sicilian variety of garlic, known as Nubia red garlic, on an ex vivo experimental model of ulcerative colitis, involving isolated LPS-treated mouse colon specimens. Both extracts were able to counteract LPS-induced cyclooxygenase (COX)-2, tumor necrosis factor (TNF)-α, nuclear factor-kB (NF-kB), and interleukin (IL)-6 gene expression in mouse colon. Moreover, the same extracts inhibited prostaglandin (PG)E₂, 8-iso-PGF_2α, and increased the 5-hydroxyindoleacetic acid/serotonin ratio following treatment with LPS. In particular, GHE showed a better anti-inflammatory profile. The anti-inflammatory and antioxidant effects induced by both extracts could be related, at least partially, to their polyphenolic composition, with particular regards to catechin. Concluding, our results showed that GHE and GWE exhibited protective effects in colon, thus suggesting their potential use in the prevention and management of ulcerative colitis.

Evaluation of Anticolitis and Antioxidant Properties of Bixa orellana (Bixaceae) Leaf Hydroethanolic Extract on Acetic Acid-Induced Ulcerative Colitis in Rats

Background

Ulcerative colitis is an idiopathic inflammatory bowel disease characterized by tissue damage, diarrhea, anemia, and loss of body weight. Tissue damage occurs as a result of uncontrolled activation of the immune response and an increase in free radicals, which have a strong effect on the pathogenesis of inflammatory bowel disease. The incidence and prevalence of this inflammatory disease continue to increase worldwide. Maceration of Bixa orellana leaves in palm wine is used in traditional medicine to treat diarrhea, dysentery, and hemorrhoids in the Adamaoua region of Cameroon.

Objective

The present work evaluated the preclinical effects (ie, antioxidant, hematological, and histological activities) of the hydroethanolic extract of Bixa orellana leaves in an in vivo, rat acetic acid-induced ulcerative colitis model.

Methods

Thirty-six female rats weighing between 165 and 180 g were fasted for 18 hours and then anesthetized with ether. A dose of 1 mL acetic acid (5%) was administered rectally through a catheter in all rats except the normal control group, which received distilled water (1 mL) instead. Treatments began 48 hours after rectal administrations of acetic acid or water, and all animals were treated twice daily for 7 days. The normal control group and the colitis control group received PO distilled water (10 mL/kg), the positive control received orally loperamide (5 mg/kg, and the 3 test groups received orally the hydroethanolic extract of Bixa orellana at 100, 200, and 400 mg/kg, respectively. During treatment, the number of diarrheal stools and weight change were assessed. At the end of the treatment, the animals were put to death under ether anesthesia. Blood was collected postmortem for evaluation of hematological and antioxidant parameters. The abdomen was opened via a midline incision and the colon was removed and emptied of all contents to assess histological and antioxidant parameters.

Results

During treatment, the number of diarrheal stools was significantly decreased from day 3 in animals treated with 100 (P < 0.05), 200 (P < 0.05), and 400 (P < 0.01) mg/kg extract compared with the colitis control group. The change in body weight of all extract-treated rats decreased significantly from day 3 (–5.55%; P < 0.05) to day 8 (–13.80%; P < 0.01) compared with the normal control. In the colitis control, this change ranges from –6.15% on day 2 to –15.13% on day 8. Extract treatment with 100, 200, and 400 mg/kg significantly reduced (P < 0.05) the number of lesions and the relative weight of the colon. The levels of red blood cells, neutrophils, and total white blood cells decreased in the colitis control group, whereas treatment with the extract at doses of 100, 200, and 400 mg/kg was associated with a significant increase in these hematological parameters. Catalase and superoxide dismutase activity and glutathione concentrations all increased significantly (P < 0.01) in blood and colon in all extract-treated animals, whereas levels of malondialdehyde and nitric oxide were significantly decreased (P < 0.01) compared with the colitis control animals.

Conclusions

The hydroethanolic extract of Bixa orellana leaves had protective effects against acetic acid-induced ulcerative colitis in rats that was associated with inhibited production of free radicals believed to be responsible for oxidative stress, hematological disorders, and tissue damage in this animal model.

Effects of hydro-ethanolic extract of leaves of Maesa lanceolata (Mursinaceae) on acetic acid-induced ulcerative colitis in rats

Ulcerative colitis is a form of inflammatory bowel disease that is characterized by acute and chronic inflammation. The aim of this work was to evaluate the efficacy of hydroethanolic extract of Maesa lanceolata leaves on acetic acid-induced colitis in rats. Colitis was induced by rectal administration of 1 mL of acetic acid (4%) in 25 male rats except the normal control group which received distilled water after 18 h of fasting followed by Ketamine (50 mg/kg)/Valium (10 mg/kg) anesthesia. Five hours later, the normal control and the negative control received distilled water, the positive control received prednisolone (5 mg/kg) and the three test groups received extract at 100, 200 and 400 mg/kg bw for eight days. During treatment, rectal temperature, the number and quality of the stools, and changes in body weight were assessed. At the end of the treatment, the animals were sacrificed, blood, colon, liver and spleen were collected for evaluation of hematological, inflammatory, antioxidant and histological parameters. Rectal temperature and the number of diarrheal, mucus and bloody stools were significantly reduced (P < 0.01) during treatment in the test and positive control groups with an increase in body weight change. The extract significantly (P < 0.01) reduced myeloperoxidase, TNF-α, interleukin 6, NO and MDA levels and significantly (P < 0.01) increased SOD levels, of GSH and catalase activity in the colon and blood. This extract also increased (P < 0.01) levels of red blood cells, hemoglobin, hematocrit, total white blood cells and blood platelets, prevented leukocyte infiltration in the liver and colon.

Exosomes: A new frontier under the spotlight for diagnosis and treatment of gastrointestinal diseases

Exosomes are small plasma membrane-bound multivesicular bodies ranging in size from 20-100 nm. Exosomes are degraded fragments of mRNA, microRNA, and enriched in proteins, lipids, and nucleic acid. They are produced in the endosomes of most eukaryotic cells and once secreted, exosomes are involved in cell to cell communication and remodeling of the matrix in the extracellular compartment. Exosome biogenesis plays a crucial role in cellular development, inflammation, immunity, hemostasis, carcinogenesis, and degeneration. Due to their unique biochemical and biophysical properties, exosomes serve a variety of functions including biomarkers of diagnostic and prognostic significance. Besides, there is an increasing level of evidence to expand our understanding of the exosomes as novel therapeutic agents. Inflammatory bowel disease (IBD) such as Crohn's disease and ulcerative colitis, hepatic fibrosis, and gastrointestinal malignancies such as colorectal cancer are the potential avenues where exosomes can be applied as cell therapy and immunotherapy and have shown promising results in several in-vitro and animal models. The purpose of this review article is to highlight the emerging role of exosomes as the diagnostic and therapeutic tool in various diseases involving the gastrointestinal tract like IBD, hepatocellular carcinoma, and colon cancer. A thorough literature search was performed on databases such as PubMed, Ovid Medline, and EMBASE to achieve the objectives of this review article.

Gastroprotective effects of both aqueous and ethanolic extracts of Lemon verbena leaves against indomethacin-induced gastric ulcer in rats

OBJECTIVES

Regarding Lemon verbena gastroprotective effects, we investigated the protective effects of Lemon verbena extracts on reducing gastric ulcer induced by indomethacin.

MATERIALS AND METHODS

Rats received aqueous and ethanolic extracts of Lemon verbena (50, 100, and 200 mg/kg), zileuton (100 mg/kg), montelukast (10 mg/kg), or 1% Tween 80 in presence or absence of indomethacin (100 mg/kg).

RESULTS

Indomethacin produced stomach ulcer and increased neutrophils percentage and MDA level compared with the control group (P<0.001). Co-administration of indomethacin and zileuton, montelukast and ethanolic (200 mg/kg) (P<0.001), aqueous extract (200 mg/kg) (P<0.05) reduced ulcer compared with the indomethacin group (P<0.001). Ethanolic extracts (100 and 200 mg/kg) and aqueous extract (200 mg/kg) reduced the MDA level (P<0.001). Ethanolic (50, 100, and 200 mg/kg) and aqueous extracts (200 mg/kg) significantly decreased neutrophils percentage compared with the indomethacin group (P<0.001).

CONCLUSION

Aqueous and particularly ethanolic extracts of Lemon verbena have protective effects on indomethacin-induced gastric ulcers.

Multidirectional Pharma-Toxicological Study on Harpagophytum procumbens DC. ex Meisn.: An IBD-Focused Investigation

In the present study, we investigated the water extract of Harpagophytum procumbens DC. ex Meisn. in an experimental model of inflammatory bowel diseases (IBDs). Additionally, a microbiological investigation was carried out to discriminate the efficacy against bacterial and fungal strains involved in IBDs. Finally, an untargeted proteomic analysis was conducted on more than one hundred colon proteins involved in tissue morphology and metabolism. The extract was effective in blunting the production of oxidative stress and inflammation, including serotonin, prostaglandins, cytokines, and transcription factors. Additionally, the extract inhibited the growth of Candida albicans and C. tropicalis. The extract was also able to exert a pro-homeostatic effect on the levels of a wide plethora of colon proteins, thus corroborating a protective effect. Conversely, the supraphysiological downregulation of cytoskeletal-related proteins involved in tissue morphology and antimicrobial barrier function suggests a warning in the use of food supplements containing H. procumbens extracts.

Relationships Between Chemical Structure and Antioxidant Activity of Isolated Phytocompounds from Lemon Verbena

Over the last few years, people have been concerned about the narrow relationship between nutrition and health leading to an increasing demand of nutraceutical products and functional food. Lemon verbena (Lippia citriodora Kunth) has been traditionally used for respiratory, digestive, and muscular diseases, showing effects that are promoted by the antioxidant activity of its phytoconstituents. The antioxidant power of several lemon verbena extracts has been tested but its isolated compounds activity has not been described. The aim of the present work was to isolate phytochemicals from a commercial lemon verbena extract through a semi-preparative high-performance liquid chromatography approach for further evaluation of its individual antioxidant activity using three different methods. The structure-antioxidant activity relationships revealed the influence of substitutions in the strong antioxidant power exerted by glycosylated phenylpropanoids, in contrast to the low antioxidant capacity showed by iridoids. Development of enriched extracts in these compounds could lead to greater antioxidant effects and improved functional ingredients to prevent chronic diseases.

Protective effects induced by alcoholic Phlomis fruticosa and Phlomis herba-venti extracts in isolated rat colon: Focus on antioxidant, anti-inflammatory, and antimicrobial activities in vitro

Phlomis fruticosa L. and P. herba-venti are species belonging to the Lamiaceae family, which have been traditionally used to prepare tonic and digestive drinks. Multiple studies also demonstrated the inhibitory effects of P. fruticosa extracts and essential oil against oxidative/proinflammatory pathways and bacterial strains deeply involved in ulcerative colitis. Considering these findings, the present study evaluated the effects of alcoholic P. fruticosa and P. herba-venti leaf extracts in isolated rat colon challenged with Escherichia coli lipopolysaccharide (LPS), an ex vivo experimental paradigm of ulcerative colitis. In this context, we assayed colon levels of pro-oxidant and proinflammatory biomarkers, including nitrites, malondialdehyde (MDA), lactate dehydrogenase (LDH), and serotonin (5-HT). Additionally, the extracts have been tested in order to evaluate possible inhibitory effects on specific bacterial and fungal strains involved in ulcerative colitis. Alcoholic P. fruticosa and P. herba-venti extracts were able to blunt LPS-induced nitrite, MDA, 5-HT, and LDH levels in isolated rat colon. The same extracts also inhibited the growth of Pseudomonas aeruginosa, E. coli, Staphylococcus aureus, Candida albicans and Candida tropicalis. In conclusion, our findings show a potential role exerted by alcoholic P. fruticosa and P. herba-venti in managing the clinical symptoms related to ulcerative colitis.

Devil's claw (Harpagophytum procumbens) and chronic inflammatory diseases: A concise overview on preclinical and clinical data

Devil's Claw is a traditional medicine that has been long used a wide range of health conditions, including indigestion, fever, allergic reactions, and rheumatism. The main compounds are iridoid glycosides, including harpagoside, harpagide, and procumbide. However, harpagoside is the most responsible for therapeutic activity, and its content is used as reference standard. Here, we analyzed and summarized preclinical and clinical studies focusing on therapeutic efficacy of devil's claw preparations in pathological conditions in which inflammation plays a key causative role.

Aloysia citrodora Paláu (Lemon verbena): A review of phytochemistry and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Aloysia citrodora Paláu (Lippia citriodora Kunth), commonly known as "lemon verbena" is a medicinal plant native to South America, North Africa, and South of Europe which is used by native people for several indications such as diarrhea, flatulence, insomnia, and rheumatism.

AIM OF THE REVIEW

Despite the wide biological activities of lemon verbena, there is no current review summarizing medicinal properties of the plant; thus, this paper aims to discuss current state of the art regarding the phytochemistry, pharmacology, and therapeutic applications of A. citrodora considering in vitro, in vivo, and clinical studies.

MATERIALS AND METHODS

Electronic databases including PubMed, Scifinder, Cochrane library, Scopus, and Science direct were searched with the scientific name of the plant and its synonyms, as well as the common name. All studies on the ethnobotany, phytochemistry, pharmacology, and clinical application of the plant until October 2017 were included in this review.

RESULTS

Despite the few number of studies on the ethnopharmacology of the plant, A. citrodora is widely assessed regarding its phytochemistry and biological activities. Neral and geranial are the main ingredients of the essential oil; whereas verbascoside is the most significant component of the extract. Biological activities such as antioxidant, anxiolytic, neuroprotective, anticancer, anesthetic, antimicrobial, and sedative effects are proved in cell cultures, as well as animal studies.

CONCLUSIONS

Several pharmacological activities have been reported for A. citrodora; however, the plant is not fully assessed regarding its safety and efficacy in human. Future well-designed human studies are essential to confirm the therapeutic benefits of this plant in clinical settings.

A Novel HPLC Method for Direct Detection of Nitric Oxide Scavengers from Complex Plant Matrices and Its Application to Aloysia triphylla Leaves

The present study aimed at developing an original pre-column HPLC assay allowing rapid characterization of nitric oxide (NO) scavengers from complex plant extracts. Sodium nitroprusside (SNP) was employed as a NO donor and spiked with an aqueous extract from Aloysia triphylla leaves prior to HPLC analysis. Relying on the ability of radical scavenging constituents to be oxidized upon reaction with radicals, this assay successfully allowed direct identification of three potential NO scavengers, including verbascoside, isoverbascoside, and luteolin-7-O-diglucuronide. These three phenolics were also individually assessed for their NO scavenging activities by using a Griess colorimetric assay. With respective IC₅₀ values of 56 ± 4, 51 ± 3, and 69 ± 5 µg/mL, verbascoside, isoverbascoside, and luteolin-7-O-diglucuronide were all reported as potent NO scavenging compounds, confirming the efficiency of the SNP spiking HPLC assay. The present method can, thus, be considered as a valuable and effective approach for speeding up the discovery of NO scavenging constituents.

The Effect of Ethanolic Extract of Lippia Citriodora on Rats with Chronic Constriction Injury of Neuropathic pain

Objective

We examined the protective effects of ethanolic extract of Lippia citriodora (L. citriodora) on rats subjected to chronic constriction injury (CCI) of sciatic nerve and possible mechanisms of actions.

Materials and Methods

In this experimental study, the extract was administered 50, 100 and 200 mg/kg, Intraperitoneally (I.P) from the surgery time for 14 consecutive days. The changes in the spinal cord levels of apoptotic factors, microglia and astroglia markers during the time course of study were assessed by western blotting on days 3, 7 and 14 post-CCI.

Results

CCI rats developed neuropathy evident from a marked mechanical allodynia, cold allodynia and thermal hyperalgesia on days 3, 5, 7, 10 and 14 post-CCI. A significant increase in the levels of Iba (a marker of microglia activation) and Bax (a proapoptotic factor) was observed three days after nerve injury. The levels of Iba remained high on day 7. In contrast, there was no difference in glial fibrillary acidic protein (GFAP) contents between sham and CCI animals. Treatment with the extract significantly attenuated behavioral changes associated with neuropathy. Bax/Bcl-2 and Iba1 were decreased in CCI animals treated with the extract.

Conclusion

The results support the evidence that microglial activation and apoptosis are correlated with pain behaviors. It is suggested that anti-allodynic and anti-hyperalgesic effects, elicited by L. citriodora, might have some degrees of association with the inhibition of microglia activation and apoptotic pathways.

Exosomes Derived from Dendritic Cells Treated with Schistosoma japonicum Soluble Egg Antigen Attenuate DSS-Induced Colitis

Exosomes are 30–150 nm small membrane vesicles that are released into the extracellular medium via cells that function as a mode of intercellular communication. Dendritic cell (DC)-derived exosomes modulate immune responses and prevent the development of autoimmune diseases. Moreover, Schistosoma japonicum eggs show modulatory effects in a mouse model of colitis. Therefore, we hypothesized that exosomes derived from DCs treated with S. japonicum soluble eggs antigen (SEA; SEA-treated DC exosomes) would be useful for treating inflammatory bowel disease (IBD). Exosomes were purified from the supernatant of DCs treated or untreated with SEA and identified via transmission electron microscopy, western blotting and NanoSight. Acute colitis was induced via the administration of dextran sulfate sodium (DSS) in drinking water (5.0%, wt/vol). Treatment with exosomes was conducted via intraperitoneal injection (i.p.; 50 μg per mouse) from day 0 to day 6. Clinical scores were calculated based on weight loss, stool type, and bleeding. Colon length was measured as an indirect marker of inflammation, and colon macroscopic characteristics were determined. Body weight loss and the disease activity index of DSS-induced colitis mice decreased significantly following treatment with SEA-treated DC exosomes. Moreover, the colon lengths of SEA-treated DC exosomes treated colitis mice improved, and their mean colon macroscopic scores decreased. In addition, histologic examinations and histological scores showed that SEA-treated DC exosomes prevented colon damage in acute DSS-induced colitis mice. These results indicate that SEA-treated DC exosomes attenuate the severity of acute DSS-induced colitis mice more effectively than DC exosomes. The current work suggests that SEA-treated DC exosomes may be useful as a new approach to treat IBD.

Optimization of Aqueous Extraction and Biological Activity of Harpagophytum procumbens Root on Ex Vivo Rat Colon Inflammatory Model

Harpagophytum procumbens has a long story of use for the treatment of inflammatory diseases. Considering both the antiinflammatory effects of H. procumbens in multiple tissues and the stability of harpagoside in artificial intestinal fluid, the aim of the present study was to explore the possible protective role of a microwave-assisted aqueous Harpagophytum extract (1-1000 μg/mL) on mouse myoblast C2C12 and human colorectal adenocarcinoma HCT116 cell lines, and isolated rat colon specimens challenged with lipopolysaccharide (LPS), a validated ex vivo model of acute ulcerative colitis. In this context, we evaluated the effects on C2C12 and HCT116 viability, and on LPS-induced production of serotonin (5-HT), tumor necrosis factor (TNF)-α, prostaglandin (PG)E₂ and 8-iso-prostaglandin (8-iso-PG)F_2α . Harpagophytum extract was well tolerated by C2C12 cells, while reduced HCT116 colon cancer cell viability. On the other hand, Harpagophytum extract reduced H₂ O₂ -induced (1 mM) reactive oxygen species (ROS) production, in both cell lines, and inhibited LPS-induced colon production of PGE₂ , 8-iso-PGF_2α , 5-HT and TNFα. Concluding, we demonstrated the efficacy of a microwave-assisted Harpagophytum aqueous extract in modulating the inflammatory, oxidative stress and immune response in an experimental model of inflammatory bowel diseases (IBD), thus suggesting a rational use of Harpagophytum in the management and prevention of ulcerative colitis in humans. Copyright © 2017 John Wiley & Sons, Ltd.

An Hydroalcoholic Chamomile Extract Modulates Inflammatory and Immune Response in HT29 Cells and Isolated Rat Colon

Inflammatory bowel diseases (IBDs) are chronic disorders characterized by disruption and ulceration of the colonic mucosa or of any part of the digestive tract (Crohn's disease). Antioxidant/anti-inflammatory herbal extract supplementation could represent an innovative approach to contrast IBDs. Clinical trials demonstrated the efficacy of natural formulas, containing chamomile, in patients with gastrointestinal disorders. This is consistent, albeit in part, with the antioxidant and anti-inflammatory properties of chamomile. The aim of the present study was to explore the possible protective role of a chamomile extract, on human colorectal adenocarcinoma HT29 cell, and rat colon specimens treated with lipopolysaccharide (LPS) to induce an inflammatory stimulus, a well established model of acute ulcerative colitis. In this context, the activities of different biomarkers of inflammation and lipid peroxidation such as ROS, myeloperoxidase (MPO), serotonin (5-HT), prostaglandin (PG)E2 , 8-iso-prostaglandin (8-iso-PG)F2α , NF-kB, tumor necrosis factor (TNF)α and interleukin (IL)-6 were assessed. We found that chamomile extract was as effective as sulfasalazine (2 mg/ml) in reducing the production of MPO, 5-HT, IL-6, NF-kB, TNFα, PGE2 and 8-iso-PGF2α , after inflammatory stimulus. The observed modulatory effects support a rationale use of chamomile supplementation as a promising pharmacological tool for the prevention and management of ulcerative colitis in humans. Copyright © 2016 John Wiley & Sons, Ltd.

Repellent and Anti-quorum Sensing Activity of Six Aromatic Plants Occurring in Colombia

Essential oils (EOs) are widely used as biopesticides and to control bacterial infections. This study describes the ability of six EOs isolated from plants cultivated in Colombia to perform as repellents against Ulomoides dermestoides and as quorum sensing (QS) inhibitors. EOs from Aloysia triphylla, Cymbopogon nardus, Lippia origanoides, Hyptis suaveolens, Swinglea glutinosa ami Eucalyptus globulus were repellents classified as Class IV, IV, IV, III, II, and II, respectively, whereas the commercial repellent IR3535 only reached Class II after 2 h exposure. All EOs presented small, but significant inhibitory properties against the QS system in Escherichia coli (pJBA132) at 25 μg/mL after 4 h exposure. These data suggest evaluated EOs from Colombia are sustainable, promising new sources of natural repellents and could be important as anti-quorum sensing molecules.

Inhibition of the DHT-induced PSA secretion by Verbascum xanthophoeniceum and Serenoa repens extracts in human LNCaP prostate epithelial cells

ETHNOPHARMACOLOGICAL RELEVANCE

Verbascum xanthophoeniceum is a mullein plant, typical of Balkan region and some parts of Turkey, traditionally used as phytotherapeutic agent due to its anti-inflammatory properties. It is rich in phenylethanoid and iridoid metabolites whose anti-inflammatory properties are under characterization.

MATERIALS AND METHODS

The role of Verbascum xanthophoeniceum crude methanolic extract and its isolated phenylethanoid glycoside verbascoside have been evaluated, in comparison to a saw palmetto extract, on a human in vitro model of androgen-regulated prostate epithelium, the LNCaP cell line. Cytotoxicity and DHT-induced free and total PSA secretion have been thoroughly studied.

RESULTS

We have found that similar to saw palmetto, Verbascum xanthophoeniceum extract and its isolated phenylethanoid glycoside verbascoside have no cytotoxicity in human LNCaP prostate epithelial cells, whereas an inhibitory effect on the DHT-induced free and total PSA secretion, a recognized anti-androgen like activity, has been shown in case of both Verbascum xanthophoeniceum extract and pure verbascoside. Furthermore, in the absence of the endogenous androgen DHT, an androgen-like activity in Verbascum xanthophoeniceum is detectable as it is for saw palmetto, suggesting that a mixed androgen-antiandrogen activity is present.

CONCLUSIONS

For the first time, Serenoa repens and Verbascum xanthophoeniceum extracts have shown an absence of cytotoxicity and an inhibitory effect on DHT-induced PSA secretion in an in vitro model of human prostate epithelium, whereas the phenylethanoid glycoside verbascoside appeared to explain only part of the Verbascum xanthophoeniceum inhibitory activity on PSA secretion.

Bioavailability of lemon verbena (Aloysia triphylla) polyphenols in rats: impact of colonic inflammation

Lemon verbena (Aloysia triphylla) infusion, a widely consumed herbal tea, contains significant amounts of polyphenols such as flavone diglucuronides and phenylpropanoid glycosides (mainly verbascoside). We have recently shown that lemon verbena infusion offers beneficial effects against dextran sodium sulphate (DSS)-induced colonic inflammation in rats. The present study aimed to evaluate the bioavailability and intestinal absorption of polyphenols derived from lemon verbena infusion in both healthy and colitic rats. For this purpose, lemon verbena infusion was given to rats ad libitum for 14 d, and then 4 % DSS was added to the infusion for 7 d. Before and after DSS administration, 24 h urinary excretion of polyphenols was determined. Flavones were excreted in the urine as conjugated aglycones, and their excretion was not significantly altered by colonic inflammation. Only trace amounts of verbascoside were excreted in the urine, but various metabolites (hydroxycinnamic acids) were detected. The urinary excretion of hydroxycinnamic acids, particularly that of caffeic acid, increased after DSS administration (P< 0·05). Only flavone aglycones (luteolin and diosmetin) were excreted in the faeces in small proportions (3·2 % of ingested flavones). Intestinal absorption of lemon verbena polyphenols was examined using an in situ intestinal perfusion model. Intestinal absorption of verbascoside and flavone diglucuronides did not significantly differ between the healthy and colitic rats. Collectively, these results show that intestinal absorption and urinary excretion of lemon verbena flavone diglucuronides were not altered by colonic inflammation, but that urinary excretion of hydroxycinnamic acids derived from verbascoside was affected in a colitic situation.