Antiulcer mechanisms of the hydroalcoholic extract from Aztec marigolds' medicinal and edible flowers (Tagetes erecta L.).

The antiulcer mechanisms of the dry extract of T. erecta flowers (DETe) were studied here. The acute ulcers induced by acidified ethanol or indomethacin were reproduced in mice pretreated with DETe (3 - 300 mg/kg). The antiulcer activity of DETe was also verified in mice pretreated with NEM, L-NAME, indomethacin, or yohimbine. The antisecretory effect of DETe was verified in rats, and its anti-Helicobacter pylori activity was determined in vitro. DETe (300 mg/kg, p.o) reduced the ethanol- or indomethacin-induced ulcer by 49 and 93%, respectively. The pre-treatment with L-NAME, NEM or yohimbine abolished the gastroprotective effect of DETe. However, DETe did not change the volume, acidity, or peptic activity in rats and did not affect H. pylori. This study expands knowledge about the antiulcerogenic potential of DETe, evidencing the role of nitric oxide, non-protein sulfhydryl groups, α2 adrenergic receptors, and prostaglandins, but not antisecretory or anti-H. pylori properties.

Geraniol accelerates the gastric healing, minimizes ulcers recurrence, and reduces anxiolytic-like behavior in ulcerated rodents by oral or inhaled route.

BACKGROUND: Geraniol (GE) is dietary acyclic monoterpene alcohol found in essential oils from aromatic plants with therapeutic value against gastric ulcers already described. HYPOTHESIS/PURPOSE: To assess whether oral GE accelerates gastric healing or prevents ulcer recurrence, and to evaluate the hypothesis that GE promotes antiulcer effects by the inhaled route and that promotes changes in the behavior of ulcerated rodents. METHODS: Gastric healing effects, underlining mechanisms, and behavioral changes were measured in80% acetic acid-induced gastric ulcer model in rats receiving GE by oral (30 mg/kg) or inhaled route (1 mg/L of air/min); whereas the effects of GE to avoid ulcer recurrence was evaluated in mice submitted to 10% acetic acid plus IL-1ß ulcer. RESULTS: GE administered by both routes accelerates gastric healing, increasing mucin and GSH levels, CAT, and GST activities, and reducing MPO activity. Moreover, oral, and inhaled GE minimized ulcer recurrence reducing gastric TNF and IL-6 levels and preserving mucin levels. Interestingly, the inhalation or oral intake of GE promotes anxiolytic-like effects in ulcerated rats. CONCLUSION: Data altogether suggest that the GE accelerates gastric healing through the strengthening of protective factors of the gastric mucosa, promoting a quality healing that reduces the recurrence of the lesion. Besides, the anxiolytic-like effect of GE may also contribute to its gastric healing action since anxiety is recognized as one of the etiologic agents of ulcers.

Extract of Tagetes erecta L., a medicinal plant rich in lutein, promotes gastric healing and reduces ulcer recurrence in rodents.

ETHNOPHARMACOLOGICAL RELEVANCE: Tagetes erecta L. (Asteraceae), popularly known as Aztec Marigold, is used in South America to treat several ailments. Despite reports that T. erecta flowers are used in folk medicine to treat gastrointestinal diseases, there is no study regarding its gastric healing effects. AIM OF THE STUDY: The effect of dry extract of T. erecta L. (DETe) in gastric healing and gastric ulcer recurrence was evaluated, contributing to the validation of the antiulcer potential of this medicinal plant. METHODS: Rats were treated orally with vehicle (1 ml/kg), omeprazole (20 mg/kg), or DETe (3, 30 or 300 mg/kg) for 7 days, twice a day. The lesion area was evaluated, and the levels of reduced glutathione (GSH) and lipoperoxides (LOOH) and the activity of the superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), and myeloperoxidase (MPO) were measured. The ulcer recurrence was evaluated in mice and induced by interleukin (IL)-1ß (1 µg/kg, i.p). The recurred area, gastric wall thickness, GSH and cytokines levels, MPO and N-acetylglucosaminidase (NAG) activities were measured. RESULTS: DETe accelerated the healing of gastric ulcers only at 300 mg/kg, reducing the ulcerated area by 66%. In parallel, DETe reduced LOOH levels, SOD, CAT and MPO activities, while increasing GST activity and mucin amount. In the recurrence model, DETe reduced the lesion area by 94%, and in parallel decreased the gastric wall thickness and TNF levels, while increasing IL-10 amount. CONCLUSIONS: Corroborating the popular use of T. erecta, DETe favors the antioxidant system and reduce gastric inflammation, accelerating the gastric healing process and reducing the ulcer recurrence.

Preparations from Campomanesia reitziana reduce the gastrointestinal motility and castor oil-induced diarrhea in a non-opioid and non-dopaminergic pathway in mice and display antimicrobial activity in vitro.

BACKGROUND: This study investigated the antidiarrheal potential of the aqueous extract (AECR) and hydroalcoholic extract of Campomanesia reitziana leaves (HECR), its ethyl acetate (EAF) and dichloromethane fractions (DCMF), and myricitrin isolated from EAF. METHODS: The total phenols and flavonoids were measured, followed by chromatography and myricitrin isolation. The 2,2-diphenyl-1-picryl-hydrazyl scavenger activity, the cytotoxicity, and the effects on LPS-induced nitrite production in intestinal epithelial cells (IEC-6) were quantified. The effect of HECR, EAF, DCMF, and AECR on intestinal motility (IT), gastric emptying (GE), and castor oil-induced diarrhea in mice was determined, as well as its antimicrobial activity. KEY RESULTS: The administration of AECR 10% (10 ml/kg, p.o), but not HECR (300 mg/kg), reduced the GE and IT by 52 and 51%. The EAF and DCMF at 300 mg/kg also reduced IT but did not change GE. Moreover, AECR and EAF, but not DCMF, inhibited the castor oil-induced diarrhea and naloxone or metoclopramide pretreatment did not change these effects. Myricitrin did not change IT and the evacuation index of mice. Finally, the dry residue of AECR inhibited bacterial growth and EAF showed bacteriostatic activity against S. aureus, E. coli, and S. typhimurium and antifungal for C. albicans. However, none of the preparations alter the viability of Giardia spp. trophozoites. CONCLUSIONS: The AECR and EAF can be effective to treat diarrhea acting through opioid- or dopaminergic type 2 receptor-independent mechanisms and by its antimicrobial actions.

The gastroprotective effect of red propolis extract from Northeastern Brazil and the role of its isolated compounds.

ETHNOPHARMACOLOGICAL RELEVANCE: Propolis has been used in folk medicine to treat gastric disorders for centuries. However, although studies have been conducted to validate the gastroprotective and anti-ulcer activity of some types of propolis, red propolis activity remains unknown. AIM OF THE STUDY: The present study aimed to evaluate the gastroprotective effect of the hydroalcoholic extract of red propolis (HERP), its mode of action, and the main compounds involved in its activity, therefore contributing to validate the chemical and pharmacological potential of this product. MATERIAL AND METHODS: The effect of HERP (30, 100 and 300 mg/kg p.o. and 30 mg/kg i.p.), and the isolated compounds vestitol (VS), neovestitol (NV), methylvestitol (MV), medicarpin (MD), and oblongifolin AB (OB) (10 mg/kg p.o.) were evaluated on gastric ulcers induced by 60% ethanol/0.3 M HCl (5 mL/kg, p.o.) in mice. Histological changes and mucin levels were assessed by HE and PAS, respectively. Moreover, oxidative stress parameters and myeloperoxidase activity were analyzed on ulcerated tissue. The effect of HERP on gastric acid secretion was evaluated by pyloric ligature model and the mechanisms involved in its gastroprotective effect were investigated by pretreating mice with L-NAME (a non-selective nitric oxide synthase inhibitor, 70 mg/kg, i.p.), NEM (a sulfhydryl group chelator, 10 mg/kg, i.p.), yohimbine (an alpha-adrenergic receptor antagonist, 2 mg/kg, i.p.) and indomethacin (a non-selective cyclooxygenase inhibitor, 10 mg/kg, i.p.). RESULTS: HERP (300 mg/kg p.o. or 30 mg/kg i.p.), MV, and MD (10 mg/kg p.o.) protected gastric mucosa against the damage induced by ethanol/HCl. Histological changes were attenuated by the HERP, MV, and MD. Moreover, HERP and MV increased mucin levels. Besides, oxidative stress and MPO activity were reduced by the three treatments. HERP did not display anti-secretory action, but its effect was abolished by indomethacin treatment. CONCLUSIONS: HERP displays gastroprotective property against ethanol/HCl-induced damage. Its effect is dependent on prostaglandins and mucin production. The compounds MV and MD may have an essential role in the activity of HERP. Our data contribute to validate the traditional use of propolis for gastric disorders.

Fruticuline A, a chemically-defined diterpene, exerts antineoplastic effects in vitro and in vivo by multiple mechanisms.

Natural products have been recognized as important bioactive compounds on the basis of their wide biological properties. Here we investigated the antitumor effect and molecular mechanisms of the diterpene Fruticuline A (fruti) from Salvia lachnostachys, in human cancer cell lineages and Solid Ehrlich Carcinoma in mice. Fruti reduced MCF-7 and HepG2 proliferation by the reduction of Cyclin D1 levels and decreased NF-κB gene levels in both cell types. Furthermore, fruti also induced apoptosis in HepG2 cells, reduced Bcl-2 gene expression and induced necroptosis by increasing Ripk in MCF-7 cells. In mice, fruti prevented tumor development and reduced Cyclin D1, Bcl-2 and Rela gene levels, and reduced the p-NF-κB/NF-κB ratio in tumor tissue. Furthermore, fruti induced necrosis and apoptosis, increased N-acetyl-ß-D-glucosaminidase and TNF-α levels and reduced IL-10 and Vegf levels in tumor tissue. Collectively, fruti exerts antitumor effects through the inhibition of the NF-κB pathway, reducing Cyclin D1 and Bcl-2 levels. In vitro the apoptosis and necroptosis pathways are involved in the cellular death, whereas in vivo, cells undergo necrosis by increased tumor inflammation and reduction of angiogenesis. Thus, fruticuline A acts in tumor cells by multiple mechanisms and represents a promising molecule for drug development in cancer treatment.

Maytenus robusta Reissek, a medicinal plant popularly used to treat digestive diseases, promotes ameliorative effects in colon and liver of mice exposed to dextran sulfate sodium.

ETHNOPHARMACOLOGICAL RELEVANCE: Maytenus robusta Reissek (Celesteraceae), popularly named as cafezinho do mato or coração de bugre, is employed to treat inflammatory digestive diseases in the south of Brazil. However, despite popular usage, the effects of this species on an experimental model of ulcerative colitis are unknown. AIM OF THE STUDY: To evaluate the effects of M. robusta extract (HEMR) on colon and liver from mice with colitis induced by dextran sulfate sodium (DSS). MATERIALS AND METHODS: Firstly, the cytotoxicity of HEMR and its effects on ROS and nitrite production in IEC-6 cells were evaluated. The experimental colitis was established by adding 3% DSS on drinking water of mice and the effects of HEMR (1-100 mg/kg, p.o, once a day by 7 days) in colonic and hepatic tissues were analyzed. RESULTS: The HEMR (1-100 µg/mL) did not alter the cell viability but reduced nitrite production of IEC-6 stimulated by LPS. Moreover, HEMR (100 mg/Kg) attenuates macro and microscopic alterations in the colon from mice exposed to DSS, as evidenced by a reduction of the colon shortening, attenuation of the epithelial erosion, submucosal edema and preservation of the Goblet cells integrity, as well as the restoration of mucin depletion. The treatment with HEMR increased GSH amount, reduced LOOH levels and normalizes CAT activity in the colon. The group treated with HEMR showed increased GST activity, reduced MPO activity and decreased inflammatory cytokines secretion (TNF and IL-6) in the colonic tissue. In the liver, HEMR increased GST activity, decreased the GPx activity and reduced IL-6 levels. Furthermore, the HEMR treatment reduced AST and ALT serum levels in mice exposed to DSS. Finally, the HEMR was able to reduce intestinal transit. CONCLUSIONS: HEMR treatment minimizes inflammation of the colon and maintaining the antioxidant homeostasis. In addition, HEMR may be a potential tool to prevent hepatic injury secondary to ulcerative colitis.

Polysaccharides from green sweet pepper increase the antineoplastic effect of methotrexate on mammary tumor cells.

This study investigated the antineoplastic effects and toxicity of long-term treatment with polysaccharides from sweet green pepper (Capsicum annuum [CAP]), and concomitant treatment with CAP + methotrexate (MTX) on mammary tumor cells in vivo and in vitro. Ehrlich tumor cells were subcutaneously inoculated in female Swiss mice. The long-term treatment (31 days) with CAP (100 mg kg-1, p.o.) reduced the tumor growth and did not induce toxicity. The combined treatment protocol of 100 mg kg-1 CAP (p.o.) + 1 mg kg-1 MTX (i.p.) for 21 days inhibited the tumor growth in 95%, higher than the inhibition induced by MTX alone (1.0 or 2.5 mg kg-1, i.p.). In tumors, both CAP and CAP + MTX decreased the gene expression of Vegf, vessel area, and IL-4 and IL-10 levels, and increased IL-6 levels and the degree of necrosis. Treatment with CAP + MTX also increased TNF-α levels in tumors. Additionally, CAP + MTX treatment reduced the viability of human MDA-MB-231 and MDA-MB-436 mammary tumor cells in culture. In fact, CAP exerted antineoplastic effects in vivo and in vitro against mammary tumor cells, possibly by modulating inflammation and angiogenesis. CAP may be a promising adjunct chemotherapy with lower toxicity.

Salvia lachnostachys Benth has antitumor and chemopreventive effects against solid Ehrlich carcinoma.

Salvia lachnostachys is an herbaceous plant with anti-inflammatory, analgesic and cytotoxic properties. This study investigated the antitumor effect of an ethanolic extract of Salvia lachnostachys leaves (EES) in a solid Ehrlich carcinoma model. Ehrlich cells were inoculated subcutaneously in the right pelvic member (2 × 106 cells) in female Swiss mice. The animals were treated with vehicle (10 mL kg-1, p.o.), EES (30 and 100 mg kg-1, p.o.), or methotrexate (2.5 mg kg-1, i.p.) for 21 days (early treatment) or 14 days (late treatment) after tumor inoculation, or 10 days before tumor inoculation and continued for 21 days after tumor inoculation (chemopreventive treatment). The acute toxicity test was performed according OECD guidelines Late treatment with EES had no antitumor effect. Early treatment with 100 mg kg-1 EES prevented tumor development, increased tumor necrosis factor-α (TNF-α) levels and decreased tumor superoxide dismutase (SOD) activity, interleukin-10 (IL-10) levels and Cyclin D1 expression, and tumor cell necrosis was observed. Chemopreventive treatment with EES for 10 and 31 days prevented tumor development in the same manner. EES treatment for 31 days decreased hepatic and tumor SOD activity, tumor IL-10 levels and Cyclin D1 expression, and increased tumor reduced glutathione, N-acetylglucosaminidase, reactive oxygen species, lipid peroxidation, TNF-α levels and Nrf2 expression. No toxicity was observed in the acute toxicity assay. In conclusion, EES had an antitumor effect by inhibiting Cyclin D1 expression and increasing inflammation with early and chemopreventive treatment. Modulation of the antioxidant system also contribute for the antitumor effects of EES.

Hesperidin, a citrus flavanone glycoside, accelerates the gastric healing process of acetic acid-induced ulcer in rats.

The flavonoid hesperidin is abundantly found in citrus fruits and is used to treat vascular diseases. Previous studies described its gastroprotective actions against stress or ethanol-induced ulcer in rodents; however, results from indomethacin-induced ulcer were controversy. Therefore, given its clinical use and contradictory findings in acute models, this study aims to evaluate the effect of hesperidin (1-10 mg/kg, p.o) on chronic gastric ulcer induced by acetic acid in rats, a model that resembles the ulcer in humans. Moreover, the effects of hesperidin on mucin levels and on inflammatory and oxidative parameters at ulcer site were also measured. The treatment with hesperidin at 3 and 10 mg/kg, once a day, by seven days, accelerated by 34 and 62%, respectively, the ulcer healing process when compared to vehicle-treated group (99.1 ±â€¯6.4 mm2). Histological and histochemistry analyses confirmed the healing effect with significant favoring of mucin production. Hesperidin also promoted the preservation of reduced glutathione levels in the gastric mucosa tissue, as well as the normalization of superoxide dismutase and catalase activities at similar levels to those found in the non-ulcerated group. In addition, flavonoid administration increased the enzymatic activity of glutathione-S-transferase by 35%. Tissue lipoperoxides and myeloperoxidase activity were reduced after hesperidin treatment. In conclusion, the flavonoid hesperidin revealed a gastric healing activity in the ulcerated mucosa, an effect that showed to be associated with the reduction of oxidative damage at ulcer site, due to the reduction of the neutrophil migration and the strengthening of the mucus barrier next to the mucosa.

Hydroalcoholic extract of Tagetes erecta L. flowers, rich in the carotenoid lutein, attenuates inflammatory cytokine secretion and improves the oxidative stress in an animal model of ulcerative colitis.

Given the role of oxidative stress in ulcerative colitis (UC) etiology, and the amount of lutein (a carotenoid with antioxidant properties) in the dry hydroalcoholic extract of Tagetes erecta flowers (DHETE), this study investigated the intestinal anti-inflammatory properties of DHETE in an animal model of UC. The amount of lutein in the extract was determined by 1H-nuclear magnetic resonance spectroscopy, and total phenols, radical scavenger capability, cytotoxicity, and effects on reactive oxygen species and nitric oxide production were evaluated in vitro. Experimental UC was established by adding 5% dextran sulfate sodium (DSS) to drinking water, with the effects of DHETE (30-300 mg/kg, once a day for 7 days) on the morphological (colon length and weight), clinical (disease activity index and body weight loss), microscopic (histological score and mucin levels), and biochemical parameters analyzed. The lutein concentration found in DHETE was 8.2%, and DHETE scavenged 2,2-diphenyl-1-picrylhydrazyl radicals at 1000 µg/mL The exposure of intestinal epithelial cells to DHETE did not change its viability but reduced reactive oxygen species and nitric oxide production after lipopolysaccharide stimulation. In vivo, DHETE (300 mg/kg) attenuated weight loss, disease activity index, colon shortening, and histopathological changes promoted by DSS intake. Moreover, DHETE increased mucin colonic staining. The treatment with DHETE decreased myeloperoxidase activity as well as tumor necrosis factor and interleukin-6 levels. The extract also increased reduced glutathione levels and catalase activity and normalized superoxide dismutase and glutathione-S-transferase activities. In conclusion, DHETE reduced colitis severity by attenuating inflammatory cytokine secretion and improved the endogenous antioxidant defense in DSS-induced UC in mice.

Artepillin C, drupanin, aromadendrin-4'-O-methyl-ether and kaempferide from Brazilian green propolis promote gastroprotective action by diversified mode of action.

ETHOPHARMACOLOGICAL RELEVANCE: The propolis is extensively used in folk medicine in natura or to prepare pharmaceutical formulations since ancient time to improve health or prevent diseases, among them gastrointestinal disorders. Aiming to contribute in the scientific validation about the popular use of Brazilian Green propolis (BGP) against gastritis and gastric ulcer, this work evaluated the antiulcer potential of isolated compounds from BGP, three prenylated p-coumaric acid derivatives and two flavonoids, respectively named: 3,5 diprenyl-4-hydroxycinnamic acid (artepillin C) (1), 3-prenyl-4-dihydroxycinnamoiloxy cinnamic acid (baccharin) (2), 3-prenyl-4-hydroxycinnamic acid (drupanin) (3), aromadendrin-4'-O-methyl-ether (4) and kaempferide (5). MATERIAL AND METHODS: The compounds were characterized by nuclear magnetic resonance and mass spectrometry. Their gastroprotective effects were evaluated against ethanol/HCl- and indomethacin-induced ulcer in mice. Further, histological, histochemical, oxidative and inflammatory parameters were analyzed at ulcerated tissue. Acid antisecretory activities also were also assessed. RESULTS: Compound 2 did not reduce the ethanol/HCl- induced ulcer at 30 mg/kg (p.o), whereas the minimum oral gastroprotective doses of 1, 3, 4 and 5 were 0.3, 0.3, 3 and 3 mg/kg, respectively. Besides, these compounds prevented ethanol/HCl-induced ulcer by intraperitoneal route, as well as indomethacin-induced ulcer by oral route. The gastroprotection was accompanied by normalization of superoxide dismutase, catalase and glutathione-S-transferase activities and reduction in myeloperoxidase activity. Moreover, the compounds 4 and 5 increased the gastric mucin content and 1 reduced TNF amount. Furthermore, 1, 3, 4 and 5 decreased volume, pH, total acidity and pepsin activity of the gastric juice from rats. CONCLUSIONS: Together, our findings showed a diversified mode of action elicited by 1, 3, 4 and 5 on the gastroprotection and contribute to explain the anti-ulcer activity reported for BGP.

Brazilian green propolis hydroalcoholic extract reduces colon damages caused by dextran sulfate sodium-induced colitis in mice.

This study investigated the effects of Brazilian green propolis hydroalcoholic extract (BPE) in 3% w/v dextran sodium sulfate (DSS)-induced colitis in mice. The effects of BPE (3, 30 and 300 mg/kg, p.o, by 7 days) on the morphological (colon length and colon weight), clinical (disease activity index and weight loss), microscopic (histological score and mucin levels) and biochemical parameters were determined. The effects of BPE (300 mg/kg, p.o) in the gastrointestinal transit of mice were also evaluated. As expected, the DSS ingestion damaged the colonic tissue, lowered the body weight, decreased the mucin levels, increased MPO activity, reduced SOD activity and GSH amount. In contrast, the treatment with BPE (300 mg/kg) significantly reduced macroscopic colonic injury and the mucosal damage in colon on histopathological examination and reversed the decrease in mucin levels induced by DSS. It also significantly normalized the SOD activity and the levels of GSH, but did not elicit any effect on MPO activity in the colon. In addition, BPE did not change the gastric emptying or the intestinal transit rate of mice. Together, these results suggested that BPE reduced the signs of DSS-induced colitis in mice through maintenance of intestinal mucin barrier and favoring intestinal antioxidant defenses.

Diuretic and natriuretic effect of luteolin in normotensive and hypertensive rats: Role of muscarinic acetylcholine receptors.

BACKGROUND: Luteolin is a very common phenolic compound found in a wide variety of natural products. Although several biological properties have already been described regarding the beneficial effect of luteolin in the cardiovascular and renal system, no scientific research explored its potential effect as a diuretic agent in experimental trials. METHODS: Groups of male normotensive (NTR) and spontaneously hypertensive rats (SHR) were orally treated with vehicle, hydrochlorothiazide or luteolin. In another experimental set, in order to verify the possible mechanisms of luteolin-induced diuresis, NTR were treated with vehicle, hydrochlorothiazide, amiloride, L-NAME, indomethacin or atropine, 1h before receiving luteolin. The cumulative urine volume, electrolytes excretion, pH and osmolality were measured at the end of the experiment (after 8h). RESULTS: Luteolin, at dose of 3mg/kg, was able to induce both diuretic and natriuretic effect in NTR and SHR groups, without interfering with urinary pH, K+ or Cl- levels. While Ca2+ content remained unchanged in urine from luteolin-treated group of NTR, luteolin reduced Ca2+ excretion in urine from SHR. The treatment with HCTZ and amiloride intensified luteolin-induced diuresis and natriuresis, with an interesting potassium-sparing effect, in addition to an increase in urinary osmolality levels. Moreover, the diuretic and natriuretic action of luteolin was fully avoided in the presence of atropine, a non-selective muscarinic receptor antagonist. CONCLUSIONS: This study revealed the diuretic and natriuretic effect of luteolin in normotensive and hypertensive rats. Our data also showed the involvement of muscarinic acetylcholine receptors for the renal effects of luteolin.