Flavonoids and antiulcerogenic activity from Byrsonima crassa leaves extracts

A potential antiviral against COVID-19 obtained from Byrsonima coccolobifolia leaves extract

In this study, we specifically focused on the crude methanolic leaf extract of Byrsonima coccolobifolia, investigating its antifungal potential against human pathogenic fungi and its antiviral activity against COVID-19. Through the use of high-performance liquid chromatography coupled with electrospray ionization ion trap tandem mass spectrometry, direct infusion electrospray ionization ion trap tandem mass spectrometry, and chromatographic dereplication procedures, we identified galloyl quinic acid derivatives, catechin derivatives, proanthocyanidins, and flavonoid glycosides. The broth dilution assay revealed that the methanolic leaf extract of B. coccolobifolia exhibits antifungal activity against Cryptococcus neoformans (IC50 = 4 μg/mL). Additionally, docking studies were conducted to elucidate the interactions between the identified compounds and the central residues at the binding site of biological targets associated with COVID-19. Furthermore, the extract demonstrated an in vitro half-maximum effective concentration (EC50 = 7 μg/mL) and exhibited significant selectivity (>90%) toward SARS-CoV-2.

Phytochemicals as Immunomodulatory Molecules in Cancer Therapeutics

Phytochemicals are natural plant-derived products that provide significant nutrition, essential biomolecules, and flavor as part of our diet. They have long been known to confer protection against several diseases via their anti-inflammatory, immune-regulatory, anti-microbial, and several other properties. Deciphering the role of phytochemicals in the prevention, inhibition, and treatment of cancer-unrestrained cell proliferation due to the loss of tight regulation on cell growth and replication-has been the focus of recent research. Particularly, the immunomodulatory role of phytochemicals, which is pivotal in unchecked cell proliferation and metastasis, has recently been studied extensively. The immune system is a critical component of the tumor microenvironment, and it plays essential roles in both preventing and promoting oncogenesis. Immunomodulation includes stimulation, amplification, or inactivation of some stage(s) of the immune response. Phytochemicals and their products have demonstrated immune regulation, such as macrophage migration, nitric oxide synthase inhibition, lymphocyte, T-cell, and cytokine stimulation, natural killer cell augmentation, and NFκB, TNF, and apoptosis regulation. There is a dearth of extensive accounts of the immunomodulatory effects of phytochemicals in cancer; thus, we have compiled these effects with mechanistic aspects of dietary phytochemicals in cancer, highlighting promising candidates and ongoing clinical trials on immunotherapeutic strategies to mitigate oncogenesis.

Thymus satureioides Coss. combats oral ulcer via inhibition of inflammation, proteolysis, and apoptosis

Oral ulcer is a frequent condition that commonly affects the tongue and in which 75% of the patients experience pain, and 25% report taste changes. The available therapies are not sufficiently effective for rapid and complete healing of tongue ulcers. We previously annotated the metabolites of Thymus satureioides (TS) aerial parts and reported their antioxidant, dermacosmeceutical and hepatoprotective properties. In this study, we performed in silico analysis, by applying network pharmacology and molecular docking, followed by experimental validation of the effect of local application of T. satureioides (TS) gel at two different concentrations on the healing of acetic-acid-induced tongue ulcer in rats. Salvianolic acid A, phloretic acid caffeate, rosmarinic acid, apigenin, and luteolin were the top bioactive ingredients of TS extract. Network pharmacology showed that the most relevant targets of these active constituents were TLR4, COX-2, MMP-9, TNF-α, and Caspase-3. Molecular docking showed that rosmarinic acid and salvianolic acid had a relatively strong binding affinity, compared to the other compounds, toward all the target proteins. Experimental validation in tongue ulcer model in rats and immunohistochemistry experiments showed that application of a gel containing TS extract (5 and 10%) was effective in healing the tongue ulcer via downregulation of COX-2, TNF-α, MMP-9, and Caspase-3. This study suggests that T. satureioides extract could act as a topical treatment for tongue ulcers by combating inflammation, apoptosis, and proteolysis. The possible treatment potential of some constituents including rosmarinic acid and salvianolic acid in oral ulcerations awaits further investigations to confirm their potency.

Chemical characterization of Brazilian savannah Byrsonima species (muricis) and their impact on genomic instability and chemopreventive effects

The identification of new drugs with few or no adverse effects is of great interest worldwide. In cancer therapy, natural products have been used as chemopreventive and chemotherapeutic agents. Plants from the Brazilian savannah belonging to the Byrsonima genus are popularly known as muricis and have attracted much attention due to their various pharmacological activities. However, there are currently no data on these plants concerning their use as chemopreventive or chemotherapeutic agents in human cell lines. The present study assessed the potential of B. correifolia, B. verbascifolia, B. crassifolia, and B. intermedia extracts as natural alternatives in the prevention and/or treatment of cancer. The chemical constituents present in each extract were analyzed by electrospray ionization-mass spectrometry (ESI-MSN). The mutagenic/antimutagenic (micronucleus assay), genotoxic/antigenotoxic (comet assay), apoptotic/necrotic (acridine orange/ethidium bromide uptake), and oxidative/antioxidative (CM-H₂DCFDA) effects of the extracts and their influence on gene expression (RTqPCR) were investigated in nonmetabolizing gastric (MNP01) and metabolizing hepatocarcinoma (HepG2) epithelial cells to evaluate the effects of metabolism on the biological activities of the extracts. The genotoxicity, mutagenicity, and apoptotic effects observed in HepG2 cells with B. correifolia and B. verbascifolia extracts are probably associated with the presence of proanthocyanidins and amentoflavone. In MNP01 cells, none of the four extracts showed mutagenic effects. B. crassifolia and B. intermedia extracts exhibited strong antimutagenicity and enhanced detoxification in HepG2 cells and antioxidant capacities in both types of cells, possibly due to the presence of gallic and quinic acids, which possess chemopreventive properties. This study identifies for the first time B. correifolia and B. verbascifolia extracts as potential agents against hepatocarcinoma and B. crassifolia and B. intermedia extracts as putative chemopreventive agents.

Galloylquinic acid derivatives from Byrsonima fagifolia leaf extract and potential antifungal activity

ETHNOPHARMACOLOGICAL RELEVANCE

Byrsonima fagifolia Niedenzu (Malpighiaceae) and other Byrsonima species are popularly employed in Brazilian traditional medicine in the form of preparations as cicatrizing, anti-inflammatory, and antimicrobial.

AIM OF THE STUDY

To characterize the phytochemical profile of the hydromethanolic extract obtained from B. fagifolia leaves (BF extract) and to evaluate the toxicity and the antifungal activity.

MATERIALS AND METHODS

The compounds from BF extract were isolated by HPLC and the structures were elucidated based on extensive analyses of 1D and 2D NMR spectra (HMQC, HMBC and COSY) data. The antifungal effect was determined by the broth microdilution method and the toxicity was evaluated on erythrocytes from sheep's blood and Galleria mellonella larvae.

RESULTS

Phytochemical investigation of the BF extract led to the isolation and characterization of pyrogallol, n-butyl gallate, 3,4-di-O-galloylquinic acid, 3,5-di-O-galloylquinic acid, 3,4,5-tri-O-galloylquinic acid, and 1,3,4,5-tetra-O-galloylquinic acid. The BF extract showed high content of galloylquinic acid derivatives reaching more than twenty-times the quercetin derivatives content, according to the quantification by HPLC. These galloylquinic acid derivatives, obtained during this study, and quercetin derivatives, previously isolated, were submitted to the antifungal assays. The BF extract inhibited yeast growth mainly against Cryptococcus spp., at concentrations of 1-16 μg/mL, comparable to isolated compounds galloylquinic acid derivatives. However, the quercetin derivatives as well as quinic acid, gallic acid, and methyl gallate showed lower antifungal effect compared with galloylquinic derivatives. In addition, the BF extract had no hemolytic effect and no toxicity on G. mellonella.

CONCLUSION

The phytochemical analysis revealed that galloylquinic acid derivatives are the major compounds in the leaves of B. fagifolia and they are associated to anti-cryptococcal activity and presented reduced toxicity.

An insight into the anti-ulcerogenic potentials of medicinal herbs and their bioactive metabolites

ETHNOPHARMACOLOGICAL RELEVANCE

Peptic ulcer disease (PUD) ranks top among the most prominent gastrointestinal problems prevalent around the world. Long-term use of non-steroidal anti-inflammatory drugs, pathogenic infection by Helicobacter pylori, imbalances between gastrointestinal regulatory factors and pathological hyperacidity are major contributors towards the development of peptic ulcers. Although synthetic drugs of multiple pharmacological classes are abundantly available, inadequacy of such agents in ensuring complete recovery in not uncommon. Therefore, pharmacological explorations of herbal products including plant extracts and their respective isolated phytoconstituents, for potential gastroprotective and antiulcer properties, are regular practice among the scientific community. Moreover, the historical preferences of a significant share of world population towards herbal-based medication over modern synthetic drugs also contribute significantly to such endeavors.

AIM OF THE REVIEW

This review has endeavored to present ethnomedicinal and pharmacological prospects of a significant number of authenticated plant species in terms of their capacity to exert gastroprotection and antiulcer activities both in vitro and in vivo. The information delineated along the way was further subjected to critical analysis to ascertain the possible future prospects of such findings into designing plant-derived products in future for the treatment of peptic ulcer.

MATERIALS AND METHODS

Electronic version of prominent bibliographic databases, including Google Scholar, PubMed, Scopus, ScienceDirect, Wiley Online Library, SpringerLink, Web of Science, and MEDLINE were explored extensively for the identification and compilation of relevant information. The plant names and respective family names were verified through the Plant List (version 1.1) and World Flora Online 2021. All relevant chemical structures were verified through PubChem and SciFinder databases and illustrated with ChemDraw Ultra 12.0.

RESULTS

A colossal number of 97 plant species categorized under 58 diverse plant families have been discussed in the review for their gastroprotective and antiulcer properties. In vivo illustrations of the pharmacological properties were achieved for almost all the species under consideration. 29 individual phytoconstituents from these sources were also characterized with similar pharmacological potentials. Majority of the plant extracts as well as their constituents were found to exert their gastroprotective effects through antioxidative pathway featuring both enzymatic and nonenzymatic mechanism. Moreover, active inhibition of acid secretion, upregulation of gastroprotective mediators and downregulation of pro-inflammatory cytokines, were also associated with a prominent number of plants or products thereof.

CONCLUSIONS

Comparative evaluations of the plant sources for their antiulcer activities, both as individual and as combination formulations, are necessary to be conducted in human subjects under properly regulated clinical conditions. Moreover, the efficacy and safety of such products should also be evaluated against those of the currently available treatment options. This will further facilitate in ascertaining their suitability and superiority, if any, in the treatment of peptic ulcer diseases. Implementation of these endeavors may eventually lead to development of more efficient treatment options in the future.

UPLC-PDA-MS/MS Profiling and Healing Activity of Polyphenol-Rich Fraction of Alhagi maurorum against Oral Ulcer in Rats

Camelthorn, Alhagi maurorum Boiss, family Fabaceae has long been used in African folk medicine owing to its richness in pharmacologically active metabolites. The crude extract (CEAM), ethyl acetate fraction (EFAM) and n-butanol (BFAM) fraction of A. maurorum aerial parts were investigated for their total polyphenols and oral antiulcer activity using in-vitro and in-vivo models. The major phenolic compound was isolated from the polyphenol-rich EFAM fraction and identified by conventional and spectroscopic methods of analysis as isorhamnetin-3-O-rutinoside. Furthermore, standardization of EAFM using UPLC-PDA-UV quantified isorhamnetin-3-O-rutinoside as 262.91 0.57 g/mg of the fraction. Analysis of EFAM using UPLC-PDA-MS/MS revealed tentative identification of 25 polyphenolic compounds. EFAM exhibited the most potent free radical scavenging activity against DPPH, with an IC₅₀ (27.73 ± 1.85 µg/mL) and an FRAP value of (176.60 ± 5.21 μM Trolox equivalent (TE)/mg fraction) in comparison with CEAM and BFAM. Acetic acid-induced oral ulcers in a rat model were used to evaluate the healing properties of A. maurorum aerial parts. EFAM significantly decreased tumor necrosis factor-alpha (TNF-α) and interleukin-2 (IL-2) by 36.4% and 50.8%, respectively, in the ulcer tissues while, CEAM and BFAM exhibited lower activity at the same dose. In addition, EFAM led to a significant (p < 0.0001) rise in the expression of proliferating cell nuclear antigen (PCNA), a cell proliferation marker. A. maurorum exhibited a potent healing effect in acetic acid-induced oral ulcers in rats by mitigating the release of pro-inflammatory cytokines and improving PCNA expression.

Recent advances in interactions between polyphenols and plant cell wall polysaccharides as studied using an adsorption technique

Polyphenols include flavonoids, phenolic acids, tannins and lignans which are known to have antioxidant, UV protection and antimicrobial properties. Among them the most commonly investigated are flavonoids and phenolic acids, which, due to their plant origin, may interact with the plant cell wall (PCW) components, specifically with its polysaccharides. Knowledge concerning the nature of the interactions between these components may be used in the production of functional food or in the development of food packaging materials with additional properties. The content of polyphenols in such products is responsible for their colour and taste, and may also act as a natural preservative. On the other hand, the PCW components may have protective role of polyphenols which has impact on their release in the human digestive system. Therefore, this review is an attempt to summarize the current state of knowledge that emerged after 2017 concerning the interaction of PCW components with polyphenols, with a particular focus on hemicellulose and pectin.

A review of plant metabolites with metal interaction capacity: a green approach for industrial applications

Rapid industrial development is responsible for severe problems related to environmental pollution. Many human and industrial activities require different metals and, as a result, great amounts of metals/heavy metals are discharged into the water and soil making them dangerous for both human and ecosystems and this is being aggravated by intensive demand and utilization. In addition, compounds with metal binding capacities are needed to be used for several purposes including in activities related to the removal and/or recovery of metals from effluents and soils, as metals' corrosion inhibitors, in the synthesis of metallic nanoparticles and as metal related pharmaceuticals, preferably a with minimum risks associated to the environment. Plants are able to synthesize an uncountable number of compounds with numerous functions, including compounds with metal binding capabilities. In fact, some of the plants' secondary metabolites can bind to various metals through different mechanisms, as such they are excellent sources of such compounds due to their high availability and vast diversity. In addition, the use of plant-based compounds is desirable from an environmental and economical point of view, thus being potential candidates for utilization in different industrial activities, replacing conventional physiochemical methods. This review focuses on the ability of some classes of compounds that can be found in relatively high concentrations in plants, having good metal binding capacities and thus with potential utilization in metal based industrial activities and that can be involved in the progressive development of new environmentally friendly strategies.

Phytochemistry, antifungal and antioxidant activity, and cytotoxicity of byrsonima gardneriana (A. Juss) extract

OBJECTIVE

To determine the phytochemical composition of Byrsonima gardneriana (A. Juss) leaf extract (BGE) and its antifungal activity against Candida spp., antioxidant potential and in vitro cytotoxicity.

MATERIAL AND METHODS

BGE was obtained and submitted to Gas Chromatography Coupled to Mass Spectrometry for phytochemical analysis. The ethanolic extract was tested for its antifungal activity against C. albicans and non-albicans reference strains and clinical isolates in addition to inhibition of C. albicans growth kinetics. It was also tested for antioxidant potential in the presence of phenylhydrazine and reactive oxygen species (ROS). And cytoxicity in human erythrocytes. The data were analyzed by one-way Analysis of Variance (ANOVA) followed by Tukey's or Dunnett's post-hoc test, with α = 0.05.

RESULTS

Pyroglutamic acid (90.77 %), eucalyptol (89.61 %) and octanoic acid (76.22 %) were the major compounds detected in BGE, P (%) is the percent probability of compound identification, according to the mass spectra library. The extract showed fungistatic activity, with MIC of 125 μg/mL against most tested strains. While BGE showed low hemolytic activity on all blood types tested herein, it could not prevent osmotic stress in human erythrocytes. The extract did not have oxidizing effects in the presence of phenylhydrazine, but it showed antioxidant potential against ROS when tested at 31 μg/mL and 62 μg/mL.

CONCLUSION

B. gardneriana extract showed antifungal activity against Candida spp., demonstrated low hemolytic potential, no oxidant activity in human erythrocytes and antioxidant activity against ROS. This study opens avenues for the study of BGE as a promising biocompatible antifungal agent.

Comparative Polyphenol Composition, Antioxidant and Anticorrosion Properties in Various Parts of Panax ginseng Extracted in Different Solvents

Panax ginseng C.A. (P. ginseng) Meyer has been in use since ancient times for its therapeutic activities. Although several studies have investigated the roles of phytoconstituents in human and animal health, no comparative studies have been conducted to test the efficacy of P.ginseng leaf, fruit and root. Therefore, this study aimed to identify the antioxidant and anticorrosion activities of ginseng prepared using five different solvents. The methanolic fruit extract showed comparatively good activity in all assays. The total phenolic content (TPC) was higher in fruit (95.21 mg/g), followed by leaf (39.21 mg/g) extracted in methanol solvent compared other solvents. The total flavonoid content (TFC) of fruit methanolic extract was 50.21 mg/g, which was followed by fruit extracted in ethanol (41.33 mg/g). The same phenomenon was observed in all antioxidant studies. Through Ultrahigh Performance Liquid Chromatography (UHPLC), the presence of 23 phenolic components categorized as hydroxycinnamic acids, hydroxybenzoic acids and a few other groups that play a vital role in antioxidation was identified. Phenols such as chlorogenic acid (1002.2 μg/g), gentisic acid (854.21 μg/g) and rutin (165.32 μg/g) were found in higher amounts in fruit whereas leaf showed significant amounts of m-coumaric acid (185.32 μg/g) and p-coumaric acid (125.24 μg/g). The anti-corrosive property of the fruit extract of the ginseng with methanol as a solvent was analyzed for a copper specimen exposed to 1 M HCl medium and found to have 96% corrosion inhibition efficiency at a 1000-ppm concentration. The smooth surface of the specimen exposed to corrosive media shown in a field emission scanning electron microscope (FESEM) image confirms that the specimen was protected from corrosion, and energy-dispersive X-ray spectroscopy (EDX) spectra show that the loss of Cu is reduced in inhibited metal surface. Atomic force microscopy (AFM) images and surface roughness factor also validate the corrosion inhibition characteristic of ginseng plant extract.

Selectivity of Current Extraction Techniques for Flavonoids from Plant Materials

Flavonoids have a broad spectrum of established positive effects on human and animal health. They find an application in medicine for disease therapy and chemoprevention, whence the interest in flavonoids increases. In addition, they are used in food and cosmetic industries as pigments and biopreservatives. Plants are an inexhaustible source of flavonoids. The most important step of plant raw material processing is extraction and isolation of target compounds. The quality of an extract and efficiency of a procedure are influenced by several factors: Plant material and pre-extracting sample preparation, type of solvent, extraction technique, physicochemical conditions, etc. The present overview discusses the common problems and key challenges of the extraction procedures and the different mechanisms for selective extraction of flavonoids from different plant sources. In summary, there is no universal extraction method and each optimized procedure is individual for the respective plants. For an extraction technique to be selective, it must combine an optimal solvent or mixture of solvents with an appropriate technique. Last but not least, its optimization is important for a variety of applications. Moreover, when the selected method needs to be standardized, it must achieve acceptable degree of repeatability and reproducibility.

UPLC-qTOF-MS Phytochemical Profile and Antiulcer Potential of Cyperus conglomeratus Rottb. Alcoholic Extract

Cyperus has been commonly used as a multi-use medicinal plant in folk medicine worldwide. The objectives of our study were to determine the different metabolites in the Cyperus conglomeratus Rottb. methanol extract, and to assess its in vivo gastroprotective effect in ethanol-induced gastric ulcer model in rats. Serum levels of galactin-3 and TNF-α were employed as biochemical markers. To pinpoint for active agents, comprehensive metabolites profiling of extract via UPLC-qTOF-MS/MS was employed. A total of 77 chromatographic peaks were detected, of which 70 were annotated. The detected metabolites were categorized into phenolic acids and their derivatives, flavonoids, stilbenes, aurones, quinones, terpenes, and steroids. Rats were divided into six groups; healthy control, ulcer control, standard drug group, and 25, 50, 100 mg/kg of C. conglomeratus treated rats. Pre-treatment with C. conglomeratus alcohol extract significantly reduced galactin-3, and TNF-α in ethanol-induced ulcer model at 25, 50, and 100 mg/kg. Further histopathological and histochemical studies revealed moderate erosion of superficial epithelium, few infiltrated inflammatory cells, and depletion of gastric tissue glycoprotein in the ulcer group. Treatment with the extract protected the gastric epithelial cells in a dose-dependent manner. It could be concluded that C. conglomeratus extract provides significant gastroprotective activity in ethanol-induced gastric ulcer and ought to be included in nutraceuticals in the future for ulcer treatment.

Potential Antiulcer Agents From Plants: A Comprehensive Review

Background:

Peptic ulcer is a deep gastrointestinal erosion disorder that involves the entire mucosal thickness and can even penetrate the muscular mucosa. Nowadays, several plants and compounds derived from it have been screened for their antiulcer activity. In the last few years, there has been an exponential growth in the field of herbal medicine. This field has gained popularity in both developing and developed countries because of their natural origin and less side effects.

Objective:

This review aims to provide a comprehensive summary of currently available knowledge of medicinal plants and phytoconstituents reported for their anti-ulcer properties.

Methods:

The worldwide accepted database like SCOPUS, PUBMED, SCIELO, NISCAIR, ScienceDirect, Springerlink, Web of Science, Wiley, SciFinder and Google Scholar were used to retrieve available published literature.

Results:

A comprehensive review of the present paper is an attempt to list the plants with antiulcer activity. The review narrates the dire need to explore potential chemical moieties that exert an antiulcer effect, from unexploited traditional plants. Furthermore, the present study reveals the intense requirement to exploit the exact mechanism through which either the plant extracts or their active constituents exhibit their antiulcer properties.

Conclusion:

This article is the compilation of the plants and its constituents reported for the treatment of peptic ulcers. The Comprehensive data will surely attract the number of investigators to initiate further research that might lead to the drugs for the treatment of ulcers. As sufficient scientific data is not available on plants, most of the herbals cannot be recommended for the treatment of diseases. This can be achieved by research on pure chemical structures derived from plants or to prepare new lead compounds with proven beneficial preclinical in vitro and in vivo effects. However, a lot remains to be done in further investigations for the better status of medicinal plants.

Antiulcer properties of fruits and vegetables: A mechanism based perspective

Gastric ulcer is the damage caused to mucosal layer of the stomach under the action of various factors like high levels of acid and pepsin, invasion by Helicobacter pylori, etc. Although most cases have been controlled and the rate of ulcer occurrence has reduced over the last few decades, gastric ulcer still holds a prime concern today. A range of palliative medicines comprising proton pump inhibitors, H2 receptor antagonists, COX-2 inhibitors (coxibs) is widely in use and patients have also been administered with acid suppression therapies. But these remedies aggravate the condition of patients causing severe side effects, or rather impart temporary relief. Therefore, it is highly imperative to develop safe and effective therapies for the treatment of gastric ulcer. Nature provides us various fruits and vegetables that can combat gastric ulcer through multiple mechanisms; predominantly via antioxidant, anti-inflammatory, antisecretory, antimicrobial, anticholinergic and cytoprotective activity, inhibition of small intestinal propulsion etc. Various phytochemicals from fruits and vegetables such as phenolics, flavonoids, tannins and saponins play a vital role in the prevention and cure of gastric ulcer. This review is a compendium of all fruits and vegetables known for their profound antiulcer effect and their underlying mechanisms of action.

A Review on the Phytochemistry, Pharmacology, and Pharmacokinetics of Amentoflavone, a Naturally-Occurring Biflavonoid

Amentoflavone (C30H18O10) is a well-known biflavonoid occurring in many natural plants. This polyphenolic compound has been discovered to have some important bioactivities, including anti-inflammation, anti-oxidation, anti-diabetes, and anti-senescence effects on many important reactions in the cardiovascular and central nervous system, etc. Over 120 plants have been found to contain this bioactive component, such as Selaginellaceae, Cupressaceae, Euphorbiaceae, Podocarpaceae, and Calophyllaceae plant families. This review paper aims to profile amentoflavone on its plant sources, natural derivatives, pharmacology, and pharmacokinetics, and to highlight some existing issues and perspectives in the future.

The Effects of Methanolic Extract of Melissa officinalis on Experimental Gastric Ulcers in Rats

BACKGROUND

Melissa officinalis (MO) has potent antioxidant activity. Recent research has demonstrated the anti-ulcer properties of some medicinal plants through their antioxidant properties.

OBJECTIVES

The aim of this study was to evaluate the effects of methanolic extracts of MO on experimental gastric ulcers in rats.

MATERIALS AND METHODS

Male Wistar rats (200 - 250 g) were starved for 24 hours prior to the induction of gastric ulceration by either indomethacin (48 mg/kg/oral) or water immersion restraint (WIR) stress. Experimental rats received either ranitidine (25 mg/kg) or MO extract (150, 300 and 450mg/kg) orally 2 hours prior to WIR stress or indomethacin treatment, for the evaluation of their gastroprotective effects. The control group received the same volume of saline. Gastric lesions were scored according to the surface of lesions on the ulcer index. Superoxide dismutase (SOD) and glutathione peroxidase (GPX) were determined as measures of antioxidant defense, and malondialdehyde (MDA) was determined to measure tissue oxidation.

RESULTS

MO extract (150 and 300 mg/kg) significantly decreased the ulcer index in both the indomethacin (1.3 ± 0.09 and 1.5 ± 0.19, respectively) and WIR stress groups (1.5 ± 0.17 and 1.5 ± 0.22, respectively), as compared to the control rats (2.5 ± 0.28) (P < 0.01). MO extract (450 mg/kg) significantly reduced ulcer index readings in WIR stress rats (1.8 ± 0.31 vs. 2.4 ± 0.15 in the WIR group), however, MO extract at a dose of 450 mg/kg did not prevent indomethacin-induced gastric ulceration (2.4 ± 0.26). There was no significant difference in the ulcer index for MO extract- (150 and 300 mg/kg) and ranitidine-treated rats (P > 0.05). Also, MO extract (150 and 300 mg/kg) significantly reduced MDA serum levels (0.69 ± 0.6 µmol/L and 0.85 ± 0.24 µmol/L, respectively, vs. 4.5 ± 1.9 µmol/L in the saline group) and significantly increased antioxidants' SOD activities (296.3 ± 146.4 U/mL and 561.4 ± 120 U/mL, respectively, vs. 190.2 ± 63.8U/mL in the control group) and GPX levels (8273 ± 3049 U/mL and 14574 ± 5012 U/mL, respectively), compared to the control (3236 ± 1699 U/mL).

CONCLUSIONS

Our results showed that MO extract may have a gastroprotective effect against experimental gastric ulcers in rats. The exact mechanism has not yet been determined, but it may be due to enhancing enzymatic antioxidant defenses and inhibiting lipid peroxidation.

Hypoglycemic Effects of sesquiterpene lactones from Byrsonima crassifolia

The novel dimeric guaianolides sesquiterpene lactone Byrsoninas A and B from seed hexane extract of Byrsonima crassifolia were identified. Streptozotocin-induced mildly diabetic and severely diabetic mice were treated with these oral administrations at a dosage of 20 mg/kg of body weight per day for 30 days. Also the protective effect in vitro in RIN-5F cells against oxidative stress was investigated and TNF-α and IL-6 levels were measured. Both Byrsonina types reduced blood glucose, cholesterol, triglyceride, lipoprotein, and transaminase levels and increased HDL-cholesterol, antioxidant enzymes, and TBARS-reactive substance levels. Byrsoninas A and B both improved this glucose metabolism by reducing insulin resistance and by stimulating insulin production due to protection effect for pancreatic β-cells against oxidative stress, lipid abnormalities were reduced and, chronic inflammation responses were alleviated producing a hepatoprotective role.

LDH, proliferation curves and cell cycle analysis are the most suitable assays to identify and characterize new phytotherapeutic compounds

Brazilian flora biodiversity has been widely investigated to identify effective and safe phytotherapeutic compounds. Among the investigated plant species, the Byrsonima genus exhibits promising biological activities. This study aimed at evaluating the cytotoxicity of B. correifolia, B. verbascifolia, B. fagifolia and B. intermedia extracts using different assays in two cell lines (primary gastric and HepG2 cells). The different extract concentrations effects on cell viability were assayed using the MTT, aquabluer, neutral red and LDH assays. Non-cytotoxic concentrations were selected to generate cell proliferation curves and to assess cell cycle kinetics by flow cytometry. Byrsonima extracts differentially affected cell viability depending on the metabolic cellular state and the biological parameter evaluated. B. fagifolia and B. intermedia extracts exhibited lower cytotoxic effects than B. correifolia and B. verbascifolia in all assays. The results obtained with LDH and flow cytometry assays were more reliable, suggesting that they can be useful in the screening for herbal medicine and to further characterize these extracts as phytotherapeutic compounds.

Anti-ulcer activity of essential oil constituents

Essential oils have attracted considerable worldwide attention over the last few decades. These natural products have wide-ranging pharmacological activities and biotechnological applications. Faced with the need to find new anti-ulcer agents and the great effort on the development of drugs for the treatment of ulcers, in this review, the anti-ulcer activities of 21 bioactive compounds found in essential oils are discussed.

Chemical composition of the bark of Tetrapterys mucronata and identification of acetylcholinesterase inhibitory constituents

The secondary metabolite content of Tetrapterys mucronata, a poorly studied plant that is used occasionally in Brazil for the preparation of a psychotropic plant decoction called "Ayahuasca", was determined to establish its chemical composition and to search for acetylcholinesterase (AChE) inhibitors. The ethanolic extract of the bark of T. mucronata exhibited in vitro AChE inhibition in a TLC bioautography assay. To localize the active compounds, biological profiling for AChE inhibition was performed using at-line HPLC-microfractionation in 96-well plates and subsequent AChE inhibition bioautography. The analytical HPLC-PDA conditions were transferred geometrically to a preparative medium-pressure liquid chromatography column using chromatographic calculations for the efficient isolation of the active compounds at the milligram scale. Twenty-two compounds were isolated, of which six are new natural products. The structures of the new compounds (9, 10, 16-18, and 20) were elucidated by spectroscopic data interpretation. Compounds 1, 5, 6, 9, and 10 inhibited AChE with IC50 values below 15 μM.

Gastroprotective effect of ethanolic extract of Curcuma xanthorrhiza leaf against ethanol-induced gastric mucosal lesions in Sprague-Dawley rats

Herbal medicines appeared promising in prevention of many diseases. This study was conducted to investigate the gastroprotective effect of Curcuma xanthorrhiza leaf in the rats induced gastric ulcer by ethanol. Normal and ulcer control received carboxymethycellulose (5 mL/kg) orally, positive control was administered with 20 mg/kg omeprazole (reference drug) and 2 groups were received 250 mg/kg and 500 mg/kg of the leaf extract, respectively. To induce of gastric ulcers formation, ethanol (5 mL/kg) was given orally to all groups except normal control. Gross ulcer areas, histology, and amount of prostaglandin E₂, superoxide dismutase and malondialdehyde were assessed to determine the potentiality of extract in prevention against gastric ulcers. Oral administration of extract showed significant gastric protection effect as the ulcer areas was remarkably decreased. Histology observation showed less edema and leucocytes infiltration as compared with the ulcer control which exhibited severe gastric mucosa injury. Furthermore, the leaf extract elevated the mucus weight, level of prostaglandin E₂ and superoxide dismutase. The extract also reduced malondialdehyde amount significantly. Results showed leaf extract of Curcuma xanthorrhiza can enhanced the gastric protection and sustained the integrity of gastric mucosa structure. Acute toxicity test did not showed any sign of toxicity (2 g/kg and 5 g/kg).

Isolation of arginase inhibitors from the bioactivity-guided fractionation of Byrsonima coccolobifolia leaves and stems

Byrsonima coccolobifolia leaf and stem extracts were studied in the search for possible leishmanicidal compounds using arginase (ARG) from Leishmania amazonensis as a molecular target. Flavonoids 1b, 1e-1g, 2a, 2b, and 2d-2f showed significant inhibitory activity, with IC50 values ranging from 0.9 to 4.8 μM. The kinetics of the most active compounds were determined. Flavonoids 1e, 1f, 2a, 2b, and 2e were characterized as noncompetitive inhibitors of ARG with dissociation constants (Ki) ranging from 0.24 to 3.8 μM, demonstrating strong affinity. Structure-activity relationship studies revealed some similarities in the structural features of flavonoids related to ARG activity.

Gastric antisecretory and cytoprotective effects of hydroalcoholic extracts of Plumeria alba Linn. leaves in rats

OBJECTIVE

This study was conducted to evaluate the antiulcerogenic property of hydroalcoholic extract obtained from the leaves of Plumeria alba Linn.

METHODS

Antiulcer assays were performed using the protocols of ulcer induced by non-steroidal anti-inflammatory drugs, ethanol and pylorus ligation. The hydroalcoholic extract (HAPA), and various fractions of HAPA like, n-hexane extract (HPA), ethyl acetate extract (EAPA) and n-butanol extract (BPA) were administered at doses of 200 and 400 mg/kg for HAPA and 100 and 200 mg/kg for fractions of extracts. Parameters of gastric secretion (volume, pH, total protein, and free and total acidity) were determined by the pylorus ligation model. Parameters like aspartate aminotransferase and alanine aminotransferase were also determined in ethanol-induced ulcer model. To determine the mechanism of action, role of nitric oxide was also evaluated.

RESULTS

EAPA and BPA (100 and 200 mg/kg, p.o.) showed gastric ulcer-healing effect in indomethacin-induced ulcer model, while HAPA (200 mg/kg) and HPA showed no significant antiulcer effect. Both EAPA and BPA showed gastric cytoprotective effect in ethanol-induced gastric ulcer and inhibited gastric secretion in pylorus-ligated rats.

CONCLUSION

The results of the present study show that some hydroalcoholic extract of Plumeria alba L. displays antiulcer activity, as demonstrated by the significant inhibition of ulcer formation induced by different models, which is consistent with the literature report in folk medicine.

Chemistry and biological activities of flavonoids: an overview

There has been increasing interest in the research on flavonoids from plant sources because of their versatile health benefits reported in various epidemiological studies. Since flavonoids are directly associated with human dietary ingredients and health, there is need to evaluate structure and function relationship. The bioavailability, metabolism, and biological activity of flavonoids depend upon the configuration, total number of hydroxyl groups, and substitution of functional groups about their nuclear structure. Fruits and vegetables are the main dietary sources of flavonoids for humans, along with tea and wine. Most recent researches have focused on the health aspects of flavonoids for humans. Many flavonoids are shown to have antioxidative activity, free radical scavenging capacity, coronary heart disease prevention, hepatoprotective, anti-inflammatory, and anticancer activities, while some flavonoids exhibit potential antiviral activities. In plant systems, flavonoids help in combating oxidative stress and act as growth regulators. For pharmaceutical purposes cost-effective bulk production of different types of flavonoids has been made possible with the help of microbial biotechnology. This review highlights the structural features of flavonoids, their beneficial roles in human health, and significance in plants as well as their microbial production.

Flavonoids for treating venous leg ulcers

BACKGROUND

Venous leg ulcers are a major health burden: annually, in the UK alone, they contribute an estimated cost to the NHS of GBP 400 million. Flavonoids are a diverse group of naturally-occurring venotonic compounds that address certain microcirculatory parameters involved in venous leg ulcer pathophysiology.

OBJECTIVES

To evaluate the clinical effects of flavonoids on the healing of venous leg ulcers.

SEARCH METHODS

In February 2013 we searched the Cochrane Wounds Group Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 1); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE; and EBSCO CINAHL. No date or language restrictions were applied. We checked reference lists of included trials, and contacted pharmaceutical companies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that investigated the efficacy of any flavonoid-containing compound on venous leg ulcer healing in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for the review and disagreements were referred to a third author. All rejected articles were double-checked by a third author. Assessment of risk of bias and data extraction were performed independently by two authors, discrepancies were resolved by referring to the third author.

MAIN RESULTS

Of the nine studies (1075 participants): five investigated Micronised Purified Flavonoid Fraction (MPFF), and four investigated hydroxyethylrutosides (HR).Meta-analysis involving 723 participants from five trials - four of which were characterised by poor reporting - showed more venous leg ulcers were healed in the MPFF groups than in the control groups (RR 1.36; 95% CI 1.07 to 1.74). However, the most rigorously conducted trial, which was at low risk of bias, did not show any additional benefit of MPFF (RR 0.94; 95% CI 0.73 to 1.22). Since this trial was unpublished, the possibility of publication bias in trials involving flavonoids must be acknowledged. Overall, the quality of reporting of trials on HR was also poor. Pooling three trials, all at unclear risk of bias, involving 279 participants showed a statistically significant effect in favour of HR with respect to number of ulcers healed (RR 1.70; 95% CI 1.24 to 2.34).

AUTHORS' CONCLUSIONS

Although the overall estimate of the number of healed ulcers appeared to show a significant effect in favour of flavonoids (both MPFF and HR), this result needs to be interpreted cautiously, as most of these trials were poorly reported, and so had an unclear risk of bias for randomisation, allocation concealment, blinding and methods for addressing incomplete outcome data. There was also a possibility of publication bias.

Hadi AH, Golbabapour S, Hajrezaie M, Hassandarvish P, Ali HM, Majid NA, Abdulla MA. Acute toxicity and gastroprotection studies with a newly synthesized steroid

BACKGROUND

Synthetic steroids, such as 9α-bromobeclomethasonedipropionate, have shown gastroprotective activity. For example, the potent glucocorticoid steroid, beclomethasone dipropionate, has been used for treatment of bowel ulcerations. The purpose of the present study was to evaluate the effect of a synthetic steroid, (20S)-22-acetoxymethyl-6β-methoxy-3α,5-dihydro-3'H-cyclopropa[3α,5]-5α-pregnane (AMDCP), on ethanol-induced gastric mucosa injuries in rats.

METHODOLOGY/PRINCIPAL FINDING

Rats were divided into 8 groups. The negative control and ethanol control groups were administered Tween 20 (10%v/v) orally. The reference control group, 20 mg/kg omeprazole (10% Tween 20, 5 mL/kg), was administrated orally. The experimental groups received 1, 5, 10, 15 or 20 mg/kg of the AMDCP compound (10% Tween 20, 5 mL/kg). After 60 min, Tween 20 and absolute ethanol was given orally (5 mL/kg) to the negative control group and to the rest of the groups, and the rats were sacrificed an hour later. The acidity of gastric content, gastric wall mucus and areas of mucosal lesions were assessed. In addition, histology and immunohistochemistry of the gastric wall were assessed. Prostaglandin E2 (PGE2) and malondialdehyde (MDA) content were also measured. The ethanol control group exhibited severe mucosal lesion compared with the experimental groups with fewer mucosal lesions along with a reduction of edema and leukocyte infiltration. Immunohistochemical staining of Hsp70 and Bax proteins showed over-expression and under-expression, respectively, in the experimental groups. The experimental groups also exhibited high levels of PGE2 as well as a reduced amount of MDA. AMDCP decreased the acidity and lipid peroxidation and increased the levels of antioxidant enzymes.

CONCLUSION/SIGNIFICANCE

The current investigation evaluated the gastroprotective effects of AMDCP on ethanol-induced gastric mucosal lesions in rats. This study also suggests that AMDCP might be useful as a gastroprotective agent.

Dietary nitrate and reductive polyphenols may potentiate the vascular benefit and alleviate the ulcerative risk of low-dose aspirin

The recent revelation that daily low-dose aspirin not only lowers risk for vascular events, but also can notably decrease risk for a range of adenocarcinomas, decreasing total cancer mortality by about 20%, makes it highly desirable to implement this protective strategy on a population-wide basis. Nonetheless, the fact that low-dose aspirin approximately doubles risk for serious gastrointestinal bleeding may impede health authorities from recommending its use by people judged to be at low cardiovascular risk. Nitric oxide (NO) exerts gastroprotective effects by boosting blood flow and mucus production in the gastric mucosa - effects which demonstrably oppose the pro-ulcerative impact of aspirin and other NSAIDs. A nitrate-rich diet, as well as ingestion of reductive catechol-bearing polyphenols, can collaborate in promoting NO generation in gastric juice, and they are protective in rodent models of gastric ulceration. Moreover, a high-nitrate diet, as well as certain reductive polyphenols such as epicatechin and quercetin, can exert platelet-stabilizing effects complementary to those of aspirin, and act in other ways to preserve vascular health. Hence, diets rich in nitrate and reductive polyphenols have the potential to amplify the vascular-protective benefits of low-dose aspirin, while diminishing its pro-ulcerative risk. Low-dose aspirin may be more unequivocally recommendable within the context of such a dietary strategy.

The activity of lowering intraocular pressure of cassiae seed extract in a DBA/2J mouse glaucoma model

PURPOSE

To evaluate the activity of lowering intraocular pressure (IOP) by Cassiae seed in the DBA/2J mouse glaucoma model.

METHODS

Young male (mean age: 3 months) inherited glaucoma mice (BDA/2J) were enrolled in this study. To evaluate the potential of Cassiae seed in the treatment of glaucoma, all subjects were divided into 6 groups. There were 1 sham group, positive control identified as group 2 topical brimonidine and group 3 oral acetazolamide, and groups 4-6 Cassiae seed extract (CSE) groups. The lactate dehydrogenase (LDH) level in the anterior aqueous humor and the changes of IOP were investigated. Contents of total polyphenol glycosides in the CSE were measured using a high-performance liquid chromatography (HPLC) method. Chromatographic separation was performed on a Cosmosil 5C(18)-MS reverse-phase HPLC column (4.6×250-mm i.d., 5 μm) with methanol/0.1% H(3)PO(4) as the mobile phases in a gradient elution mode at a flow rate of 1.0 mL/min and an injection volume of 10 μL. The wavelength of UV detector was set at 254 nm.

RESULTS

The LDH level in the anterior aqueous humor and IOP significantly decreased after treatment with CSE. The IOP-lowering effect of CSE was comparable to those of oral acetazolamide and brimonidine instillation. There were no abnormal findings in the external appearance, and body weight change after treatment with CSE for 5 weeks. Chrysophanol and physcion were measured by an HPLC method to obtain total polyphenol glycosides of the CSE, and were involved in the IOP-lowering function.

CONCLUSION

Cassiae seed may be safe and beneficial for treating glaucoma due to its significant IOP- and LDH-lowering activities.

Mechanisms of Gastroprotective Effects of Ethanolic Leaf Extract of Jasminum sambac against HCl/Ethanol-Induced Gastric Mucosal Injury in Rats

Jasminum sambac is used in folk medicine as the treatment of many diseases. The aim of the present investigation is to evaluate the gastroprotective effects of ethanolic extracts of J. sambac leaves against acidified ethanol-induced gastric ulcers in rats. Seven groups of rats were orally pre-treated with carboxymethylcellulose (CMC) as normal group, CMC as ulcer group, 20 mg/kg of omeprazole as positive group, 62.5, 125, 250, and 500 mg/kg of extract as the experimental groups, respectively. An hour later, CMC was given orally to normal group and acidified ethanol solution was given orally to the ulcer control, positive control, and the experimental groups. The rats were sacrificed after an hour later. Acidity of gastric content, the gastric wall mucus, ulcer areas, and histology and immunohistochemistry of the gastric wall were assessed. Gastric homogenates were determined for prostaglandin E₂ (PGE₂), superoxide dismutase (SOD), andmalondialdehyde (MDA) content. Ulcer group exhibited significantly severe mucosal injury as compared with omeprazole or extract which shows significant protection towards gastric mucosal injury the plant promotes ulcer protection as it shows significant reduction of ulcer area grossly, and histology showed marked reduction of edema and leucocytes infiltration of submucosal layer compared with ulcer group. Immunohistochemistry showed overexpression of Hsp70 protein and downexpression of Bax protein in rats pretreated with extract. Significant increased in the pH, mucus of gastric content and high levels of PGE₂, SOD and reduced amount of MDA was observed.

Effect of Byrsonima crassa and phenolic constituents on Helicobacter pylori-induced neutrophils oxidative burst

Byrsonima crassa Niedenzu (Malpighiaceae) is used in Brazilian folk medicine for the treatment of diseases related mainly to gastric ulcers. In a previous study, our group described the gastric protective effect of the methanolic extract from the leaves of B. crassa. The present study was carried out to investigate the effects of methanolic extract and its phenolic compounds on the respiratory burst of neutrophils stimulated by H. pylori using a luminol-based chemiluminescence assay as well as their anti-H. pylori activity. The suppressive activity on oxidative burst of H. pylori-stimulated neutrophils was in the order of methyl gallate > (+)-catechin > methanol extract > quercetin 3-O-α-l-arabinopyranoside > quercetin 3-O-β-d-galactopyranoside > amentoflavone. Methyl gallate, compound that induced the highest suppressive activity with IC₅₀ value of 3.4 μg/mL, did not show anti-H. pylori activity. B. crassa could be considered as a potential source of natural antioxidant in gastric ulcers by attenuating the effects on the damage to gastric mucosa caused by neutrophil generated reactive oxygen species, even when H. pylori displays its evasion mechanisms.

Gastroprotective activity of hydroalcoholic extract obtained from the leaves of Brassica oleracea var. acephala DC in different animal models

ETHNOPHARMACOLOGICAL RELEVANCE

Brassica oleracea var. acephala DC has been extensively used in Brazilian traditional medicine to treat gastric ulcer.

AIM OF THE STUDY

This study was conducted to evaluate the antiulcerogenic property of hydroalcoholic extract obtained from the leaves of Brassica oleracea.

MATERIALS AND METHODS

Antiulcer assays were performed using the protocol of ulcer induced by ethanol/HCl, and non-steroidal anti-inflammatory drugs (NSAIDs). Parameters of gastric secretion (volume, pH and [H(+)]) were determined by the pylorus ligation model and mucus in gastric contents.

RESULTS

In the ethanol-induced ulcer model, we observed a significant reduction in all the parameters analyzed, obtaining curative ratios of 58.8 ± 11.5, 86.2 ± 12.2 and 42.8 ± 6.6% for the groups treated with 50 and 100mg/kg of extract and omeprazole (30 mg/kg), respectively. The dose of 25mg/kg of hydroalcoholic extract of Brassica oleracea showed no significant results. In the indomethacin-induced ulcer, the percentages of ulcer inhibition were 64.3 ± 9.9, 66.4 ± 12.3 and 81.2 ± 7.5% for the groups treated with 50 and 100mg/kg extract and positive control (cimetidine, 100mg/kg), respectively. The results showed a significant increase in pH and mucus production in the groups treated with Brassica oleracea when compared with the control group. No sign of toxicity was observed in the acute toxicity study.

CONCLUSIONS

The results of the present study show that hydroalcoholic extract of Brassica oleracea displays antiulcer activity, as demonstrated by the significant inhibition of ulcer formation induced using different models. The data suggest that the effectiveness of the extract is based on its ability to stimulate the synthesis of mucus, increase pH and decrease H(+) ions in the stomach. This work corroborates the ethnopharmacology use of Brassica oleracea preparations, contributing to its pharmacological validation by suggesting that preparations obtained from Brassica oleracea could be used for the development of new phytopharmaceuticals for the treatment of gastric ulcer.

Role of phenolic compounds in peptic ulcer: An overview

Peptic ulcer is the most common gastrointestinal tract (GIT) disorder in clinical practice, which affects approximately 5-10% of the people during their life. The use of herbal drugs for the prevention and treatment of various diseases is constantly developing throughout the world. This is particularly true with regard to phenolic compounds that probably constitute the largest group of plants secondary metabolites. Phenolic compounds have attracted special attention due to their health-promoting characteristics. In the past ten years a large number of the studies have been carried out on the effects of phenolic compounds on human health. Many studies have been carried out that strongly support the contribution of polyphenols to the prevention of cardiovascular diseases, cancer, osteoporosis, neurodegenerative diseases, and diabetes mellitus, and suggest a role in the prevention of peptic ulcer. Polyphenols display a number of pharmacological properties in the GIT area, acting as antisecretory, cytoprotective, and antioxidant agents. The antioxidant properties of phenolic compounds have been widely studied, but it has become clear that their mechanisms of action go beyond the modulation of oxidative stress. Various polyphenolic compounds have been reported for their anti-ulcerogenic activity with a good level of gastric protection. Besides their action as gastroprotective, these phenolic compounds can be an alternative for the treatment of gastric ulcers. Therefore, considering the important role of polyphenolic compounds in the prevention or reduction of gastric lesions induced by different ulcerogenic agents, in this review, we have summarized the literature on some potent antiulcer plants, such as, Oroxylum indicum, Zingiber officinale, Olea europaea L., Foeniculum vulgare, Alchornea glandulosa, Tephrosia purpurea, and so on, containing phenolic compounds, namely, baicalein, cinnamic acid, oleuropein, rutin, quercetin, and tephrosin, respectively, as active constituents.

Strawberry polyphenols attenuate ethanol-induced gastric lesions in rats by activation of antioxidant enzymes and attenuation of MDA increase

Background and Aim

Free radicals are implicated in the aetiology of gastrointestinal disorders such as gastric ulcer, colorectal cancer and inflammatory bowel disease. Strawberries are common and important fruit due to their high content of essential nutrient and beneficial phytochemicals which seem to have relevant biological activity on human health. In the present study we investigated the antioxidant and protective effects of three strawberry extracts against ethanol-induced gastric mucosa damage in an experimental in vivo model and to test whether strawberry extracts affect antioxidant enzyme activities in gastric mucosa.

Methods/Principal Findings

Strawberry extracts were obtained from Adria, Sveva and Alba cultivars. Total antioxidant capacity and radical scavenging capacity were performed by TEAC, ORAC and electron paramagnetic resonance assays. Identification and quantification of anthocyanins was carried out by HPLC-DAD-MS analyses. Different groups of animals received 40 mg/day/kg body weight of strawberry crude extracts for 10 days. Gastric damage was induced by ethanol. The ulcer index was calculated together with the determination of catalase and SOD activities and MDA contents. Strawberry extracts are rich in anthocyanins and present important antioxidant capacity. Ethanol caused severe gastric damage and strawberry consumption protected against its deleterious role. Antioxidant enzyme activities increased significantly after strawberry extract intake and a concomitantly decrease in gastric lipid peroxidation was found. A significant correlation between total anthocyanin content and percent of inhibition of ulcer index was also found.

Conclusions

Strawberry extracts prevented exogenous ethanol-induced damage to rats' gastric mucosa. These effects seem to be associated with the antioxidant activity and phenolic content in the extract as well as with the capacity of promoting the action of antioxidant enzymes. A diet rich in strawberries might exert a beneficial effect in the prevention of gastric diseases related to generation of reactive oxygen species.

Antiulcer and antioxidant activity of ethanolic extract of Passiflora foetida L

Passiflora foetida L. (Passifloraceae), a widely growing perennial climber, has been used in traditional medicine for treating many ailments. The objective of the present study was to evaluate the effects of ethanolic extract of P. foetida (EEPF) whole plant on gastric ulcer. The antiulcer effects of EEPF at 100 and 200 mg/kg doses were evaluated on ethanol and aspirin-induced gastric ulcer models. The antioxidant parameters and histological changes in gastric tissue of ulcer rats were also determined in both the models. P. foetida treatment significantly (P < 0.01) reduced the ulcer index and significantly (P < 0.01) increased the gastric pH of both ethanol and aspirin-induced ulcer rats. P. foetida showed significant (P < 0.01) reduction in lipid peroxidation and increase in reduced glutathione levels. The observations confirm that EEPF whole plant has antiulcer and antioxidant activities.

Byrsonima fagifolia Niedenzu Apolar Compounds with Antitubercular Activity

Bioassay-guided fractionation of the chloroform extract of Byrsonima fagifolia leaves led to the isolation of active antitubercular compounds alkane dotriacontane (Minimal Inhibitory Concentration—MIC, 62.5 μg mL⁻¹), triterpenoids as bassic acid (MIC = 2.5 μg mL⁻¹), α-amyrin acetate (MIC = 62.5 μg mL⁻¹), a mixture of lupeol, α- and β-amyrin (MIC = 31.5 μg mL⁻¹) and a mixture of lupeol, and acetates of α- and β-amyrin (MIC = 31.5 μg mL⁻¹). The antimycobacterial activity was determined by the Microplate Alamar Blue Assay (MABA) and the structures of promising compounds were determined by spectroscopic analysis. This investigation constitutes the first report of a chemical and antitubercular study of apolar compounds from B. fagifolia Niedenzu (IK).

Abarema cochliacarpos: gastroprotective and ulcer-healing activities

ETHNOPHARMACOLOGICAL RELEVANCE

Abarema cochliacarpos (Gomes) Barneby & Grimes (Mimosaceae) is a species--in folk medicine of Lagarto city, Sergipe state, northeastern Brazil--reputed to heal gastric ulcer and gastritis.

AIM OF THE STUDY

Chloroform (CE) and methanolic (ME) extracts as well as ethyl acetate fraction (AF), butanolic fraction (AC) and aqueous fraction (AQF) of the methanolic extract of Abarema cochliacarpos bark were evaluated against acute gastric ulcer. The AC fraction was selected to assess its activity in ulcer healing and its gastroprotective effects via mucus and gastric secretion.

MATERIAL AND METHODS

The gastroprotective action of CE and ME extracts and the fractions of the latter were evaluated in a rodent experimental model. The action mechanisms, involvements of the antisecretory action and mucus production, toxicological and healing activity of the AC (150 mg/kg, p.o.) were evaluated. We also used histological analysis (HE and PAS) and immunohistochemical (PCNA, COX-2, VEGF and HSP-70) assays to evaluate the effects of Abarema cochliacarpos.

RESULTS

CE (200 and 400 mg/kg, p.o.) and ME (100, 200 and 400 mg/kg, p.o.) extracts were able to protect gastric mucosa against absolute ethanol. Respective inhibitions produced were: 65.31% and 83.80% by the first; 91.69%, 96.75% and 99.80% by the second; and 74.24% by the AC fraction. Antisecretory and mucus production effects were exhibited by the AC fraction, which also accelerated the healing of ulcerated gastric mucosa by stimulating proliferation factors (PCNA) and induced healing factors including COX-2, VEGF and HSP-70.

CONCLUSION

All these results suggest that Abarema cochliacarpos (Gomes) Barneby & Grimes presents gastroprotective effects and wound-healing properties.

Determination of catechin diastereomers from the leaves of Byrsonima species using chiral HPLC-PAD-CD

When catechins are found in plant extracts, they are almost always identified as catechin and/or epicatechin probably due to stereoselectivity of the enzymes involved in the biosynthesis of these substances. However, the lack of reports regarding to ent-catechin as well as ent-epicatechin does not necessarily mean that these compounds have not been produced. In fact, most of the previous reports used chromatographic conditions not suitable for such separation. This article describes a simple and reliable analytical HPLC-PAD-CD method for simultaneous determination of catechin diastereomers both in infusions and extracts from the leaves of Byrsonima species. The direct separation of catechin, ent-catechin, epicatechin, and ent-epicatechin was obtained in normal phase by HPLC-PAD-CD using Chiralcel OD-H as chiral stationary phase and n-hexane/ethanol with 0.1% of TFA as mobile phase.

Mechanisms of the gastric antiulcerogenic activity of Anacardium humile St. Hil on ethanol-induced acute gastric mucosal injury in rats

Leaves and bark infusions Anacardium humile St. Hil. (Anacardiaceae), known as in Brazil as "cajuzinho do cerrado", have been used in folk medicine as an alternative treatment for ulcers and gastritis. This study evaluated the gastroprotective activity of an ethyl acetate extract of the leaves of A. humile (AcF) and the mechanism involved in this gastroprotection. Pretreatment concentrations (50, 100, 200 mg x kg⁻¹) were administered by gavage. Following a 60 min. period, all the rats were orally administered 1 mL of absolute ethanol. One hour after the administration of ethanol, all groups were sacrificed, and the gastric ulcer index was calculated. Prostaglandin PGE₂ concentration, gastric adherent mucous, and the participation of nitric oxide (NO) and sulfhydryl compounds in the gastroprotection process were also analyzed using the most effective tested dose (50 mg x kg⁻¹). A histological study of the glandular stomach for the evaluation of the epithelial damage and mucus content was also performed. AcF significantly reduced the gastric damage produced by ethanol. This effect was statistically significant for the 50 mg x kg⁻¹ group compared to control. Also, it significantly increased the PGE₂ (by 10-fold) and mucous production, while pretreatment with NG-nitro-L-arginine methyl ester (L-NAME) or N-ethylmaleimide (NEM) completely abolished the gastroprotection. AcF has a protective effect against ethanol, and this effect, might be due to the augmentation of the protective mechanisms of mucosa.

Protective effects of Punica granatum in experimentally-induced gastric ulcers

In the present investigation standardized aqueous methanolic extract of Punica (AMP) was used for its possible ulcer protective activity in wistar rats against different experimental models. Preliminary phytochemical screening of AMP reveals the presence of saponin, tannins, and flavonoids, which may be responsible for its activity. HPTLC finger prints of AMP showed the presence of 12 spots at different (retention factor) rf values. Oral administration of AMP (490 and 980 mg/kg bw) significantly reduced the ulcer lesion index produced by alcohol, indomethacin, and aspirin, at both doses in rats. Further, in pylorus-ligated rats AMP significantly reduces the ulcer lesions, gastric volume, and total acidity. It prevents the ulceration by increasing the pH and mucus secretion in pylorus ligated rats. The present study shows the anti-ulcer activity of AMP in experimentally-induced gastric ulcers.

Gastric anti-ulcer activity of leaf fractions obtained of polar extract from Wilbrandia ebracteata in mice

Leaf fractions of Wilbrandia ebracteata were investigated for anti-ulcerogenic effects in ethanol and indomethacin-induced gastric ulcer assays in mice. Protective anti-ulcer effects were detected only in the ethanol-induced ulcer assay effects after pre-treatment with MeOH extract, MeOH chlorophyll-free, chlorophyll residue, HEX, DCM, aqueous MeOH fraction, ethyl acetate (EtOAc) and aqueous fractions. A potent anti-ulcerogenic effect was determined after pre-treatment of animals with EtOAc fraction, which was fractionated for isolation of active constituents. Seven flavonoids, 3',4',5,6,7,8-hexahydroxyflavonol, orientin, isoorientin, vitexin, isovitexin, luteolin, 6-methoxi-luteolin were isolated from the leaves of W. ebracteata (Cucurbitaceae) by chromatographic methods and identified by their spectral data. The data suggest that flavonoids are active anti-ulcerogenic compounds from leaves of W. ebracteata. The ability of scavenging free radicals was evaluated by DPPH reduction assay by TLC of flavonoids isolated.

Anti-Helicobacter pylori activity and immunostimulatory effect of extracts from Byrsonima crassa Nied. (Malpighiaceae)

Background

Several in vitro studies have looked at the effect of medicinal plant extracts against Helicobacter pylori (H. pylori). Regardless of the popular use of Byrsonima crassa (B. crassa) as antiemetic, diuretic, febrifuge, to treat diarrhea, gastritis and ulcers, there is no data on its effects against H. pylori. In this study, we evaluated the anti-H. pylori of B. crassa leaves extracts and its effects on reactive oxygen/nitrogen intermediates induction by murine peritoneal macrophages.

Methods

The minimal inhibitory concentration (MIC) was determined by broth microdilution method and the production of hydrogen peroxide (H₂O₂) and nitric oxide (NO) by the horseradish peroxidase-dependent oxidation of phenol red and Griess reaction, respectively.

Results

The methanolic (MeOH) and chloroformic (CHCl₃) extracts inhibit, in vitro, the growth of H. pylori with MIC value of 1024 μg/ml. The MeOH extract induced the production H₂O₂ and NO, but CHCl₃ extract only NO.

Conclusion

Based in our results, B. crassa can be considered a source of compounds with anti-H. pylori activity, but its use should be done with caution in treatment of the gastritis and peptic ulcers, since the reactive oxygen/nitrogen intermediates are involved in the pathogenesis of gastric mucosal injury induced by ulcerogenic agents and H. pylori infections.