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Since the authors are not responding to the editor’s requests to fulfill the editorial requirement, therefore, the article has been withdrawn. Bentham Science apologizes to the readers of the journal for any inconvenience this may have caused. The Bentham Editorial Policy on Article Withdrawal can be found at https://benthamscience.com/editorial-policies-main.php Bentham Science Disclaimer: It is a condition of publication that manuscripts submitted to this journal have not been published and will not be simultaneously submitted or published elsewhere. Furthermore, any data, illustration, structure or table that has been published elsewhere must be reported, and copyright permission for reproduction must be obtained. Plagiarism is strictly forbidden, and by submitting the article for publication the authors agree that the publishers have the legal right to take appropriate action against the authors, if plagiarism or fabricated information is discovered. By submitting a manuscript, the authors agree that the copyright of their article is transferred to the publishers if and when the article is accepted for publication. more...

Introduction: Oxidative stress plays a critical role in the pathological process of Alzheimer’s disease (AD). There is a growing interest in natural anti-oxidants and cholinesterase inhibitors from medicinal plants that may aid in the prevention against oxidative injury and in the treatment of AD. Athamanta sicula L. is an important medicinal plant. Aims: The aim of current study was to investigate the total phenolic content, antioxidant and anti-cholinesterase properties of aqueous (AqE) and methanolic extracts (MethE) from Athamanta sicula L. (A. sicula L.). Methods: The phenanthroline, ABTS free radical scavenging, β-carotene bleaching methods were utilized to assess the antioxidant capacity. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory methods were used to determine the anti-cholinesterase effect. Results: These extracts were rich in phenolic contents. It was capable of scavenging free radicals, inhibiting lipid peroxidation, and reducing agents. A. sicula L. had a remarkable cholinesterase inhibitory effect. Conclusion: These results support that A. sicula L. could be a new source of anti-oxidant and anti-cholinesterase natural drugs. Further studies on the isolation and characterization of active principles of anti-oxidant and tyrosinase inhibitory activities are needed. more...

The plants of the genus Phlomis are native to Turkey, North Africa, Europe and Asia. Phlomis bovei De Noé (Lamiaceae) is a rare Algerian endemic plant, commonly known as Kayat El Adjarah. The objective of this study is to quantify the polyphenol content and to evaluate the antioxidant activities of the ethanolic extract (EthE) of Phlomis bovei De Noé. The plant extract was prepared by macerating 100 g of ground material in 1000 ml of 85 % ethanol for 72 h, then the filtrate was evaporated using a rotary evaporator at a temperature of 45C and the filtrate was dried. The total content in polyphenols was determined using Folin Ciocalteu method. Flavonoid content in extracts was determined using Aluminum trichloride assay and the total content of tannins was determined according to Bate Smith method. The antioxidant activity was investigated in vitro by the DPPH (2, 2-diphenyl-1-picryl-hydrazyl), ABTS and iron chelating assays. The results indicate that the ethanol extract was rich in polyphenols and has an important capacity of scavenging the DPPH and ABTS free radical with an IC50 of 0.05 and 0.018 mg/ml, respectively. However, in the ferrous ions chelating ability test, PBEE extract showed moderate chelating activity (IC50 = 1.59 ± 0.05 mg/ml). To conclude, the obtained results may contribute to add possible scientific data to use Phlomis bovei industrially as herbal medicine and as supplementary sources for natural antioxidant drugs in food. Keywords: antioxidant activity, ethanol extract, Phlomis bovei De Noé, polyphenol content. more...

Reactive oxygen (ROS) and nitrogen species (RNS) are produced in all cells and play important roles in physiology. The loss of the redox balance, either by an increase of oxidant molecules ROS and RNS or by decreased antioxidant system activities cause a state of oxidative stress. Several studies are going on worldwide directed towards finding natural antioxidants of plant origin. Plants containing phenolic compounds have been reported to possess strong antioxidant activity. The objective of this study is to evaluate total polyphenols and flavonoids contents (TPC and TFC) as well as examine the in vitro antioxidative properties from aqueous extract of Ammoides atlantica (AqE). TPC was estimated utilizing Folin-Ciocalteu's reagent. TFC was evaluated utilizing the aluminum chloride method. The antioxidant properties were evaluated using metal chelating and cupric ion reducing antioxidant capacity (CUPRAC) assays. Indeed, results showed that the AqE is rich in polyphenols (141.74±0.44 µg gallic acid equivalents/ mg of dry weight), and flavonoids (61.87±6.7 µg quercetin equivalent/ mg dry weight). These phytochemical compounds possess significant antioxidant activities. The results showed that AqE exhibited a good Metal chelating activity with an IC50 of 36.57±4.73 µg/ mL. CUPRAC assay showed that AqE extract exhibited high cupric ion reducing antioxidant capacity with an A0.5 of 8.58±0.13 µg/mL. These findings provide evidence that AqE of Ammoides atlantica is a potential source of antioxidant which have many benefits towards human health. Keywords: Ammoides atlantica, aqueous extract, phenolic compounds, metal chelating and cupric ion reducing antioxidant capacity. more...

Artemisia absinthium L. is a medicinal plant largely used in traditional medicine. The aim of this study was to estimate the content of polyphenols, and flavonoids compounds and also to evaluate the antioxidant and the anti-ulcer activities of the Aqueous extract from Artemisia absinthium L. aerial parts. The Folin-Ciocalteau and AlCl3 methods were applied in order to quantify the polyphenolic and flavonoids contents, respectively. However, DPPH method was used to evaluate the in vitro antioxidant activity. Quantitative analysis of the yield and phenolic content of the aqueous extract of Artemisia absinthium showed that the yield of the aqueous extract was 19.32% and its phenolic content was 58.66 ± 2.16 μg GAE / mg dry extract for polyphenols and 6.85 μg QE / mg dry extract for the flavonoids. The antioxidant activity of the plant extract evaluated by the DPPH test is very important (IC50=45.48±0.37 µg/ml). Treatment of mice with the aqueous extract of Artemisia absinthium at a dose of 400 mg / kg significantly reduced the ulcerogenic effect of ethanol on the gastric wall with an estimated protection rate of 91%. These findings suggest that Artemisia absinthium L. aqueous extract possessed good antiulcer and antioxidant potentials. This supports the traditional claims of this plant in folklore medicine. Keywords: Artemisia absinthium, polyphenols, antioxidant activity, gastric ulcer, ethanol. more...

This study aimed to estimate the total phenolic and flavonoid contents and to evaluate the antioxidant activity of the Hydro-methanolic from Saccocalyx satureioides Coss and Dur aerial part. Total polyphenols contents were determined using Folin-Ciocalteu’s reagent. The flavonoids were estimated using the method of Aluminum chloride (AlCl3). The antioxidant capacity was evaluated using two in vitro models (the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and reducing power). Total phenolic and flavonoid content in the extract were 171.34 ±1.43 mg Gallic acid equivalent/g of dry extract (GAE/g) and 18.6 ± 0.46 mg Quercetin equivalent / g of dry extract (QE/g), respectively. The methanol extract has an important capacity to scavenge the free radical DPPH with an IC50 of 0.03 ± 0. 0024 mg/ml. In addition, the plant extract exhibited high reducing power with an IC50 of 0.54 ± 0.00625 mg/ml. The results of the present study may prove that the medicinal plants are a good resource of natural antioxidants. Keywords: Antioxidant activity, Saccocalyx satureioides, polyphenols, flavonoids. more...

Phytotherapy has known a great evolution all the world and some medicinal plants are important remedies of some diseases. Ammoides atlantica is one of the medicinal plants used in folk medicine. This study aims to estimate the total phenolics and flavonoids contents then to investigate both in vitro antioxidant activity models of aqueous extract (AqE) from Ammoides atlantica. Total polyphenol contents were determined using Folin Ciocalteu's reagent; flavonoids were quantified employing the AlCl3 Method. The in vitro antioxidant property was assessed by DPPH-scavenging radicals and lipid peroxidation assays. The results revealed that Ammoides atlantica aqueous extract presented a high total phenolic and flavonoid contents with values of 85.56±4.71 µg GAE (gallic acid equivalent)/mg and 40.55±4.09 µg QE (quercitin equivalent)/mg dry extract, respectively. This extract shows a good DPPH radical scavenging and β-carotene bleaching activities with an IC50 of 107.48±5.9 µg/mL and 130.17±5.52 µg/mL, respectively. This study indicates that the aqueous extract from Ammoides atlantica has potent antioxidant effects and may prove to be of latent health benefit as well as supplementary sources for natural antioxidants drugs. Keywords: Ammoides atlantica, aqueous extract, antioxidant activity, phenolic compounds. more...

The present study aimed to experimentally identify the essential oil of Algerian Cyperus rotundus L. and to model the interaction of some known anti-inflammatory molecules with two key enzymes involved in inflammation, 5-Lypoxygenase (5-LO) and leukotriene A4 hydrolase (LTA4H). Gas chromatography/gas chromatography–mass spectrometry (GC/GC-MS) revealed that 92.7% of the essential oil contains 35 compounds, including oxygenated sesquiterpenes (44.2%), oxygenated monoterpenes (30.2%), monoterpene hydrocarbons (11.8%) and sesquiterpene hydrocarbons (6.5%). The major identified oxygenated terpenes are humulene oxide II, caryophyllene oxide, khusinol, agarospirol, spathulinol and trans-pinocarveol Myrtenol and α-terpineol are known to exhibit anti-inflammatory activities. Several complexes obtained after docking the natural terpenes with 5-LO and LTA4H have shown strong hydrogen bonding interactions. The best docking energies were found with α-terpineol, Myrtenol and khusinol. The interaction between the natural products and amino-acid residues HIS367, ILE673 and GLN363 appears to be critical for 5-LO inhibition, while the interaction with residues GLU271, HIS295, TYR383, TYR378, GLU318, GLU296 and ASP375 is critical for LTA4H inhibition. Molecular dynamics (MD) trajectories of the selected docked complexes showed stable backbone root mean square deviation (RMSD), supporting the stability of the natural product–enzyme interaction. Communicated by Ramaswamy H. Sarma more...

In this study, Salvia aegyptiaca and Salvia verbenaca aerial part decoction and methanol extracts (SAE DE, SAE ME, SVR DE, and SVR ME) were screened for their in vitro antioxidant, anti-Alzheimer, and antidiabetic enzymes inhibition activities. The antioxidant properties of Salvia extracts were determined using DPPH radical scavenging, ABTS radical scavenging, Alkaline DMSO superoxide radical scavenging, β-carotene bleaching, reducing power, and metal chelating activity assays. All extracts showed high antioxidant capacity and the antioxidant properties with the best performance were detected in the SAE ME and SVR ME. The extracts of S. aegyptiaca and S. verbenaca showed a low inhibitory activity of acetylcholinesterase (AChE), whereas, the methanol extract of S. aegyptiaca had the highest inhibitory activity on butyrylcholinesterase (BChE) (71.60 ± 4.33% for 100 µg/ml) compared to the other extracts. In vitro inhibitory effect on diabetic enzymes showed that the ME inhibited α-amylase enzyme with an IC50 86 and 101 µg/ml for SAE and SVR, respectively. Similarly, both extracts inhibited α-glucosidase with (IC50 97 and 150 µg/ml, respectively). The decoction extracts exhibited lower activity on both enzymes. PRACTICAL APPLICATIONS: It is becoming evident that oxidative stress is involved in several acute and chronic diseases. Counteracting free radical generation has become one of the widest fields of research worldwide. This study deals with the in vitro antioxidant activity of two plants from the Salvia genus as well as the assessment of their in vitro inhibitory properties of four key enzymes implicated in diabetes and Alzheimer's disease. Concerning the practical applications of our work, it can be explored in its antioxidant part as a food supplement to prevent the excess of free radicals in the body and also in other industrial practices. Another potential use is in the prevention and amelioration of both diabetes and Alzheimer's disease symptoms for the extracts that had enzyme inhibitory activity, but this deserves further toxicological and in vivo studies. more...

In this paper, the isolation of one new iridoid glucoside, 6β-acetoxyipolamiide (1), and thirteen (2 – 14) known congeners from two Lamiaceae species, Stachys ocymastrum and Premna resinosa, leaf extracts is reported. The structural determination of the isolated compounds was performed by mono- and bidimensional NMR spectroscopic analysis as well as MS experiments. The isolates were assayed for their antiangiogenic activity by two in vivo models, zebrafish embryos and chick chorioallantoic membrane assays. The compounds with a significant antiangiogenic activity in both assays were β-hydroxyipolamiide (2), ipolamiide (3), and buddlejoside A5 (8). 6-O-α-l-(3″-O-p-Methoxycinnamoyl-4″-O-acetyl)rhamnopyranosyl catalpol (13) and 6-O-α-l-(2″-trans-caffeoyl)rhamnopyranosyl catalpol (6) showed the best antiangiogenic response on blood vessel growth in zebrafish embryos, whereas saccatoside (10) and 6-O-α-l-(2″-O - p-methoxycinnamoyl-3″-O-acetyl)rhamnopyranosyl catalpol (14) resulted in a strong reduction of capillary formation in the chorioallantoic membrane assay. more...

The phytochemical study of Galium tunetanum Lam., Rubiaceae, leaves led to the isolation of 13 compounds from the chloroform–methanol and the methanol extracts, including six iridoid glycosides, one non-glycoside iridoid, two p-coumaroyl iridoid glycosides, two phenolic acids, and two flavonoid glycosides. The structural determination of the isolated compounds was performed by mono- and bidimensional NMR spectroscopic data, as well as ESI-MS experiments. All compounds were isolated from this species for the first time. The anti-angiogenic effects of the isolated iridoids were also reported on new blood vessels formation using the chick embryo chorioallantoic membrane as in vivo model. Results showed that among the isolated iridoids tested at the dose of 2 μg/egg, asperuloside (1), geniposidic acid (2), and iridoid V1 (3) reduced microvessel formation of the chorioallantoic membrane on morphological observations using a stereomicroscope. The anti-angiogenic effects of the active compounds, expressed as percentages of inhibition versus control, were 67% (1), 59% (2), and 54% (3), respectively. In addition, the active compounds were able to inhibit angiogenesis in the chorioallantoic membrane assay, in a dose-dependent manner (0.5–2 μg/egg) as compared to the standard retinoic acid. Keywords: Anti-angiogenic activity, Asperuloside, Chick chorioallantoic membrane, Geniposidic acid, Iridoid V1 more...

The essential oils of the flowers of Magydaris tomentosa (Desf.) DC. (Apiaceae) collected in Sicily (MSi) and Algeria (MAl), respectively, were obtained by hydrodistillation, and their compositions were analysed. The analyses allowed the identification and quantification of 23 components in MSi and 60 compounds in MAl, respectively, showing a very different profile in the composition of the two populations. The main components of MSi were cembrene (28.2%), α-springene (17.5%) and β-springene (14.8%), also present in MAl but in lesser amount (0.4%, 1.8% and 0.9%, respectively), whereas the principal constituents of MAl were (E)-nerolidol (35.4%), α-costol (13.3%) and β-costol (6.8%). Both MSi and MAl exhibited a significant antibacterial activity against Staphylococcus epidermidis (minimum inhibitory concentration = 25 and 12.5 μg/mL, respectively). The chemotaxonomy markers of the species were identified. more...

Fluoride, a well-recognised harmful substance, is easily absorbed by the gastrointestinal mucosa. It is therefore conceivable that any alteration of the gastrointestinal motility can affect the rate of absorption of fluoride and leads to aggravation of its toxic effects. The effects of fluoride on gastric emptying and intestinal transit were studied in the mouse using a carboxymethyl cellulose (CMC) solution as a non-nutrient meal. The participation of the cholinergic and nitrergic systems in these effects was also evaluated. Oral gavage of 5 mM NaF had no significant effect on gastric emptying and intestinal transit of the CMC meal, whereas a decrease of gastric emptying (-33%, P more...

Mosquitoes (Diptera: Culicidae) represent a threat for millions of people worldwide, since they act as vectors for important pathogens, including malaria, yellow fever, dengue and West Nile. Second to malaria as the world's most widespread parasitic disease, infection by trematodes is a devastating public health problem. In this study, we proposed two essential oils from plants cultivated in Mediterranean regions as effective chemicals against mosquitoes and freshwater snails vectors of Echinostoma trematodes. Chemical composition of essential oils from Achillea millefolium (Asteraceae) and Haplophyllum tuberculatum (Rutaceae) was investigated. Acute toxicity was evaluated against larvae of the West Nile vector Culex pipiens (Diptera: Culicidae) and the invasive freshwater snail Physella acuta (Mollusca: Physidae), an important intermediate host of many parasites, including Echinostoma revolutum (Echinostomidae). Acute toxicity of essential oils was assessed also on a non-target aquatic organism, the mayfly Cloeon dipterum (Ephemeroptera: Baetidae). Achillea millefolium and H. tuberculatum essentials oils were mainly composed by oxygenated monoterpenes (59.3 and 71.0 % of the whole oil, respectively). Chrysanthenone and borneol were the two major constituents of Achillea millefolium essential oil (24.1 and 14.2 %, respectively). Major compounds of H. tuberculatum essential oil were cis-p-menth-2-en-1-ol and trans-p-menth-2-en-1-ol (22.9 and 16.1 %, respectively). In acute toxicity assays, C. pipiens LC50 was 154.190 and 175.268 ppm for Achillea millefolium and H. tuberculatum, respectively. P. acuta LC50 was 112.911 and 73.695 ppm for Achillea millefolium and H. tuberculatum, respectively, while the same values were 198.116 and 280.265 ppm for C. dipterum. Relative median potency analysis showed that both tested essential oils were more toxic to P. acuta over C. dipterum. This research adds knowledge on plant-borne chemicals toxic against invertebrates of medical importance, allowing us to propose the tested oils as effective candidates to develop newer and safer vector control tools. more...

The aim of this study was to investigate the chemical composition of the essential oils of three populations of Daucus aureus from three sites in Eastern Algeria (Setif, Constantine and Oum Elbouaghi) and to test their antibacterial and antioxidant activities. The essential oils were obtained by hydrodistillation and analyzed by GC and GC/MS. The major components were sabinene (30.6% and 36.2%), n-nonane (8.0% and 7.9%), α-pinene (5.5% and 6.3%) and 4-terpineol (4.4% and 6.0%) in D. aureus from Setif and Constantine populations essential oils, respectively; whereas, α-pinene (19.4%), β-pinene (12.0%) and p-cymene (12.2%) were the major components in Oum Elbouaghi essential oil population. The chemical compositions of D. aureus from Eastern Algeria are markedly different from those from Western Algeria, and likely represent new chemotypes. The antimicrobial activity of the essential oils was evaluated against four bacteria and one fungus, using the disc-diffusion method and minimal inhibitory concentration (MIC), whereas, the antioxidant activity of the essential oils was evaluated using the DPPH test. The results showed that the oils have an antimicrobial activity against the microorganisms tested, with minimal inhibitory concentration (MIC) values between 0.97 and 3.23 mg/mL and weaker antioxidant and DPPH radical scavenging activities were found in comparison to butylated hydroxyl toluene (BHT). more...

The gastric cytoprotective properties of natural honey (monofloral and polyfloral specimens) and of a glucose-fructose-sucrose-maltose mixture (GFSM) was evaluated in the rat using absolute ethanol, indomethacin and acidified acetylsalicylic acid (ASA-HCl) as necrotising agents. Prior gastric administration of honey (2.5 g/kg) to animals induced a net reduction of hemorrhagic lesions length of the mucosa. Protection of the stomach elicited by both types of honey and GFSM was almost total against ethanol-induced lesions. Similar results were also observed when using ASA-HCl except that the percent protection was 87%. The percent reduction of indomethacin-induced gastric lesions was variable according to the nature of the test solution: GFSM mixture (41.1%) < polyfloral honey (55.2%) < monofloral honey (64.0%). Perfusion of the stomach with isotonic honey resulted in (1) a 70% reduction of the area of the lesions caused by ethanol, (2) the failure to prevent the transmural potential difference fall induced by ethanol, (3) an increase of basal and histamine-stimulated acid secretion. These results suggest that sugar rich solutions (GFSM and honey) may prevent gastric damage by a mechanism involving the release of some protective agents. more...

Summary Background: We have previously shown that natural honey is able to protect the rat stomach against acute ethanol- and indomethacin-induced lesions. The present investigations were undertaken to examine the role of intraluminal osmolality in this protective effect. Methods: Mannitol, glucose-fructose-sucrose-maltose mixture (GFSM) and natural honey (300, 600, 1800 mOsmol/kg water) were given orally to rats 30 min before administration of 70% ethanol for a further 15-min period. Lesions area of the excised stomachs were evaluated. Pylorus-ligated stomachs were filled with mannitol, GFSM mixture and honey (1800 mOsmol/kg water) to test the effect of the hyperosmolar solutions on gastric fluid content and acid secretion. The rate of gastric emptying of the three test solutions (1800 mOsmol/kg) was measured by the phenol red method. Results: Intragastric administration of mannitol, GFSM mixture or honey prevented the formation of mucosal lesions in an osmolality-dependent manner. Using the pylorus-ligated stomach model, the test solutions led to a net increase of luminal fluid volume without affecting acid content. Hyperosmolar solutions presented a delayed gastric emptying if compared to a nonnutrient solution made of carboxymethyl cellulose. Conclusions: The observed results suggest that hyperosmolar solutions can prevent the formation of hemorrhagic lesions by luminal dilution of the necrotising agent and acid, an effect which may be potentiated by a lowered gastric emptying rate. more...

The gastroprotective effect of tannic acid and the aqueous extract of Quercus ilex L. root bark, Punica granatum L. fruit peel and Artemisia herba-alba Asso leaves was investigated in the rat against ethanol-induced damage. Tannic acid, Q. ilex and P. granatum extracts gave 100% precipitation of ovine haemoglobin in vitro, whereas A. herba-alba extract was devoid of any protein-binding property. Oral administration of these plant extracts or tannic acid induced a significant decrease in gastric lesions (47.7%-76%). The observed protection was more pronounced when the test solution was given at the same time with ethanol, except for Q. ilex extract. The acid content of the stomach was significantly increased by P. granatum (368%) and A. herba-alba (251%) extracts prepared in ethanol. It is suggested that monomeric and polymeric polyphenols can strengthen the gastric mucosal barrier. more...

The aim of this research was to study the potential anti-inflammatory activity of myrtle (Myrtus communis), sarsaparilla (Smilax aspera), Arabian or French lavender (Lavandula stoechas), and calamint (Calamintha nepeta) along with their apoptotic effects on the pro-inflammatory cells, and the correlation of these effects with the plants' potential anti-oxidant activity. Myrtle extract exhibited the highest inhibitory activity in the paw oedema induced by carrageenan (60% at 3 h), whereas calamint, lavender, and sarsaparilla produced inhibitions of 49%, 38%, and 47%, respectively. None of them had an effect on the TPA-induced ear oedema. Moreover, all the extracts except sarsaparilla showed different degrees of anti-oxidant activity. Lavender and myrtle at 200 μg/mL decreased cell viability by 63% and 59%, respectively, after 3 h of incubation. Neutrophil elimination through apoptosis could be implicated in the resolution of acute inflammation in the case of lavender, whereas the reduction of reactive oxygen species produced by neutrophils, such as the superoxide anion and the hydroxyl radical, could be implicated in the overall reduction of inflammation. These results may support the traditional use of these plants. more...

Flavonoids are a large heterogeneous group of benzo-gamma-pyrone derivatives, which are abundantly present in our diet. In this study we investigated the effects of six flavonoids (apigenin, genistein, quercetin, rutin, naringenin and catechin) on the gastric tone in mouse isolated stomach. The mechanical activity was recorded as changes of intraluminal pressure. All flavonoids tested produced a concentration-dependent relaxation, which was reversible after washout. The relative order of potency of the flavonoids was apigenin> or =genistein>quercetin>naringenin> or =rutin>catechin. Analysis of the chemical structure showed that the relaxant activity was progressively diminished by the presence of hydroxyl group at C-3, saturation of the C-2, C-3 double bound, saturation of the C-2, C-3 double bound coupled with lack of the C-4 carbonyl and glycosylation. The flavonoid-induced relaxations were not modified in the presence of tetrodotoxin, a voltage-dependent Na(+)-channel blocker, N(omega)-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide synthase, indomethacin, an inhibitor of cycloxygenase or tetraethylammonium, a non-selective blocker of potassium channels. In conclusion, this study provides the first experimental evidence for gastric relaxant activity of flavonoids. This action is influenced to a great extent by the structure of the molecules and it seems not to be dependent on neural action potentials, NO/prostaglandin production or activation of K(+) channels. more...

The aim of the present study was to investigate the responses induced by sodium fluoride (NaF) on gastric mechanical activity, using mouse whole-stomach preparations. The mechanical activity was recorded in vitro as changes of intraluminal pressure. In most of the preparations, NaF induced a tetrodotoxin-insensitive biphasic effect characterized by early relaxation followed by slowly developing contractile response. The contraction was dependent on the concentration of NaF, whereas the relaxation was observed at only 10–30 mmol/L NaF. The contractile effect was significantly reduced by nifedipine (an L-type Ca2+channel blocker), ryanodine or ruthenium red (inhibitors of Ca2+release from sarcoplasmic reticulum), and GF109203X (a protein kinase C inhibitor). Moreover, it was abolished by neomycin (an inhibitor of phospholipase C) and potentiated by SQ22536 (an inhibitor of adenylyl cyclase). All the drugs significantly increased the relaxation, except SQ22536, which abolished it. The present results suggest that NaF causes a complex mechanical response in the whole-stomach, which might explain gastric discomfort after fluoride ingestion. The relaxation appears owing to production of cAMP, while the contractile effects imply activation of phospholipase C, protein kinase C, influx of Ca2+, and release of Ca2+from ryanodine-sensitive intracellular store.Key words: gastric mechanical activity, mouse stomach, smooth muscle, sodium fluoride. more...

The gastroprotective effects of 70% acetone extracts of Quercus suber and Quercus coccifera leaves and of tannins (pedunculagin, castalagin, phillyraeoidin A, and acutissimin B) purified from these extracts were examined in the mouse using the ethanol-induced gastric ulcer model. Both extracts (25, 50, and 100 mg/kg), given orally, prevented the formation of ethanol-induced lesions in the stomach. The percent protection varied between 68 and 91%. Purified tannins (50 mg/kg) were also effective in protecting the stomach against ethanol, and the percent protection varied from 66 to 83%. Castalagin was the most potent. Both extracts and all of the tannins tested (10, 25, and 50 μg/mL) strongly inhibited (55−65%) the lipid peroxidation of rabbit brain homogenate. These results suggest that the gastroprotective effects of extracts of Q. suber and Q. coccifera leaves and the purified tannins in this experimental model are related to their anti-lipoperoxidant properties. Keywords: Experimental gastric ulcer; lip... more...

The cytoprotective properties of various natural honey specimens and of a glucose-fructose-sucrose-maltose mixture (GFSM) against gastric ethanol-induced lesions have been evaluated in rats. GFSM mixture and honey (2.5 g kg-1) were given orally 30 min before administration of 100% ethanol (5 ml kg-1) for a further 15-min period. Animal pretreatment with GFSM or honey prevented the formation of gastric lesions. The number and severity of haemorrhagic lesions were reduced by 98%. Stomach acid content increased by 110-703% according to honey specimens. The similar protective effects of honey and GFSM mixture suggest that carbohydrates at high concentrations behave as mild irritants that can induce adaptive cytoprotection. more...