Role of the antioxidant pathway in the healing of peptic ulcers induced by ischemia-reperfusion in male and female rats treated with Eugenia punicifolia.

Ischaemia and reperfusion (I/R)-induced gastrointestinal disorders are caused by free radicals, resulting in organ damage and functional disarrangement. This study aimed to investigate the healing effects of hydroalcoholic extracts from the leaves of Eugenia punicifolia (Kunth) DC. (HEEP) in male and female Wistar rats with I/R-induced peptic injuries, and the role of antioxidants in improving this response. After I/R-induced gastric and duodenal injuries, male and female [intact (INT) and ovariectomized (OVZ)] rats were orally treated with HEEP for 6 days. Biochemical analysis was used to determine the catalase (CAT), superoxide dismutase (SOD), and myeloperoxidase (MPO) activities, as well as malondialdehyde and reduced glutathione levels, to measure the gastric and duodenal healing process. Six days of HEEP treatment significantly decreased the I/R-induced gastric [male (73.68%), INT (52.83%), and OVZ (43.13%)] and duodenal damage [male (57.03%), INT (56.04%), and OVZ (54.83%)] in all groups. In OVZ rats, the healing effect of HEEP occurred because of the increased activity of SOD (2x) and CAT (1.16x) in the gastric mucosa. In the duodenal mucosa of INT rats, the extract reduced MPO (20.83%) activity. The 6-day HEEP treatment improved the healing of I/R-induced peptic ulcer injury, with the system acting differently in males and females. The antioxidant system is an important component of the HEEP activity during post-I/R mucosal recovery. This result revealed the importance of antioxidant compounds in minimizing the severity of I/R-related events.

The essential oil from Baccharis trimera (Less.) DC improves gastric ulcer healing in rats through modulation of VEGF and MMP-2 activity.

ETHNOPHARMACOLOGICAL RELEVANCE: Baccharis trimera (Less.) DC known as "carqueja" in Brazil has been acknowledged as a medicinal plant in folk medicine for the treatment of stomach aches and gastrointestinal disorders. AIM OF THE STUDY: The present study aimed to evaluate the gastroprotective and healing effects of essential oil from B. trimera (EOBT) against gastric ulcer lesions caused by absolute ethanol and acetic acid, respectively, and to identify the mechanism of action of this essential oil in male Wistar rats. MATERIALS AND METHODS: The plant material used to obtain EOBT was collected in the southern region of Brazil and was analyzed by chromatography-mass spectrometry (GCMS) demonstrate its characteristic chemical composition, with carquejyl acetate as its main component. Different doses of EOBT (50, 100, and 200 mg/kg) were administered orally in male Wistar rats as an acute treatment against absolute ethanol-induced gastric lesions. The gastric healing effect of EOBT (100 mg/kg) was evaluated once a day after 7, 10, and 14 days of treatment. After treatment, the stomachs of rats from all groups were collected to measure the lesion area (mm2), the activity of myeloperoxidase (MPO), and the relative expression of caspases -3, -8, -9, cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF). The zymography method was used to elucidate the activity of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) in the healing action of EOBT. We also analyzed toxicological parameters (body weight evolution and biochemical parameters) that could result after treatment with this essential oil for 14 days. RESULTS: Pretreatment with EOBT (100 and 200 mg/kg) significantly decreased the severity of gastric damage induced by absolute ethanol and decreased MPO activity in gastric tissue. After 10 and 14 days of treatment with EOBT (100 mg/kg) once a day, the lesion area was significantly reduced by 61% and 65.5%, respectively, compared to the negative control group. The gastric healing effect of EOBT was followed by a decrease in the expression of COX-1 compared to that in the negative control group. Notably, treatment with EOBT for 14 days increased the expression of VEGF compared to that using an anti-ulcer drug (lansoprazole). Additionally, analyses of MMP-2 and MMP-9 activities in the gastric mucosa confirmed the accelerated gastric healing effect of EOBT, with a significant decrease in the activity of pro-MMP-2. No sign of toxicity was observed after treatment with EOBT for 14 consecutive days. CONCLUSION: These findings indicated that EOBT was effective in preventing and accelerating ulcer healing by decreasing MPO activity, increasing VEGF expression, and decreasing MMP-2 activity. These actions collectively contribute to the rapid recovery of gastric mucosa following treatment with EOBT, without any observed toxicity.

Organic Selenium Reaches the Central Nervous System and Downmodulates Local Inflammation: A Complementary Therapy for Multiple Sclerosis?

Multiple sclerosis (MS) is an inflammatory and demyelinating disease of the central nervous system (CNS). The persistent inflammation is being mainly attributed to local oxidative stress and inflammasome activation implicated in the ensuing demyelination and axonal damage. Since new control measures remain necessary, we evaluated the preventive and therapeutic potential of a beta-selenium-lactic acid derivative (LAD-ßSe), which is a source of organic selenium under development, to control experimental autoimmune encephalomyelitis (EAE) that is an animal model for MS. Two EAE murine models: C57BL/6 and SJL/J immunized with myelin oligodendrocyte glycoprotein and proteolipid protein, respectively, and a model of neurodegeneration induced by LPS in male C57BL/6 mice were used. The preventive potential of LAD-ßSe was initially tested in C57BL/6 mice, the chronic MS model, by three different protocols that were started 14 days before or 1 or 7 days after EAE induction and were extended until the acute disease phase. These three procedures were denominated preventive therapy -14 days, 1 day, and 7 days, respectively. LAD-ßSe administration significantly controlled clinical EAE development without triggering overt hepatic and renal dysfunction. In addition of a tolerogenic profile in dendritic cells from the mesenteric lymph nodes, LAD-ßSe also downregulated cell amount, activation status of macrophages and microglia, NLRP3 (NOD-like receptors) inflammasome activation and other pro-inflammatory parameters in the CNS. The high Se levels found in the CNS suggested that the product crossed the blood-brain barrier having a possible local effect. The hypothesis that LAD-ßSe was acting locally was then confirmed by using the LPS-induced neurodegeneration model that also displayed Se accumulation and downmodulation of pro-inflammatory parameters in the CNS. Remarkably, therapy with LAD-ßSe soon after the first remitting episode in SJL/J mice, also significantly downmodulated local inflammation and clinical disease severity. This study indicates that LAD-ßSe, and possibly other derivatives containing Se, are able to reach the CNS and have the potential to be used as preventive and therapeutic measures in distinct clinical forms of MS.

Machaerium hirtum (Vell.) Stellfeld Alleviates Acute Pain and Inflammation: Potential Mechanisms of Action.

:Machaerium hirtum (Vell.) Stellfeld (Fabaceae) known in Brazil as "jacaranda de espinho" or "espinheira santa nativa" is a medicinal plant commonly used in folk medicine to treat ulcers, cough and diarrhea. This study aimed to investigate the anti-inflammatory and antinociceptive effects of hydroalcoholic extracts from M. hirtum twig (HEMh) using in vivo experimental models of nociception through the involvement of transient receptor potential channels, acid-sensing ion channel (ASIC), nitrergic, opioidergic, glutamatergic, and supraspinal pathways. Our results revealed an antinociceptive effect of HEMh mediated by the opioidergic, L-arginine-nitric oxide and glutamate systems, as well as by interactions with TRPA1/ASIC channels. The anti-inflammatory effect of HEMh evaluated with a xylene-induced ear edema and by the involvement of arachidonic acid and prostaglandin E2 (PGE2) showed involvement of the COX pathway, based on observed decreases in PGE2 levels. A phytochemical investigation of the HEMh led to the isolation of α-amyrin, ß-amyrin, allantoin, apigenin-7-methoxy-6-C-ß-D-glucopyranoside, and apigenin-6-C-ß-D-glucopyranosyl-8-C-ß-D-xylopyranoside. In conclusion, the acute oral administration of HEMh inhibits the nociceptive behavioral response in animals through the nitrergic, opioid, glutamatergic pathways, and by inhibition of the TRPA1 and ASIC channels, without causing locomotor dysfunction. In addition, its anti-inflammatory effect is associated with the COX pathway and decreased PGE2 levels.

Terminalia catappa L. infusion accelerates the healing process of gastric ischemia-reperfusion injury in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Terminalia catappa L. (Combretaceae), known as "amendoeira da praia" in Brazil, has been recognized as a medicinal plant in folk medicine for the treatment of gastrointestinal disorders and other inflammatory conditions. The present study aimed to investigate the preventive and healing effects of the infusion of leaves of T. catappa (ILTC) against gastric lesions caused by ischemia and reperfusion (I/R) injury and characterize its mechanism of action in the gastric mucosa of rats. MATERIALS AND METHODS: Different doses (30, 100, and 300 mg/kg) of ILTC were orally administered as acute and subacute treatments against I/R-induced gastric lesion in rats. After treatment, the stomach of rats was collected to measure the lesion area, redox parameters malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH) and inflammatory parameters myeloperoxidase activity (MPO), interleukin 1ß (IL-1ß) and tumor necrosis factor α (TNF-α). The activities of matrix metalloproteinases 2 and 9 (MMPs 2 and 9) were assessed by zymography method to clarify the mechanisms of the healing acceleration promoted by ILTC. RESULTS: Pretreatment with ILTC (100 mg/kg) was effective in preventing the aggravation of lesions in the acute model by reducing MPO activity by 38% relative to control group, despite the lack of clarity of this action at the macroscopical level at the lesion area (p < 0.05). After three days of treatment with ILTC (30 and 100 mg/kg), this infusion significantly reduced the lesion area by 95% and 89%, respectively, compared the control (p < 0.05). The gastric healing effect of all doses of ILTC was followed by a reduction in MPO activity (decrease by 70-78%). Compared to the negative control, an improvement in gastric healing owing to treatment with ILTC was observed and this was followed by an increase in MMP-2 (20-47%) (p < 0.05). CONCLUSION: Three days of treatment with ILTC could accelerate the healing process in I/R-induced lesions in rats. By decreasing MPO levels, ILTC enabled the action of MMP-2, which led to tissue recovery in the gastric mucosa.

Chrysin Modulates Genes Related to Inflammation, Tissue Remodeling, and Cell Proliferation in the Gastric Ulcer Healing.

Chrysin exhibits anti-inflammatory and antioxidant activities. Here, the gastroprotective effect of chrysin was investigated in mouse models of gastric ulcer induced by absolute ethanol, acetic acid, and ischemia-reperfusion injury. The gastric-healing effect was evaluated at 7 and 14 days after treatment; the mechanism of action was verified using the expression of metalloproteinase 2 (MMP-2) and 9 (MMP-9), caspase-3, cyclooxygenase 1 (COX-1) and 2 (COX-2), epidermal growth factor (EGF), and interleukin-10. Chrysin (10 mg/kg) inhibited macroscopic lesions and increased catalase activity in the mouse model established using absolute ethanol. It ameliorated the gastric ulcer caused by acetic acid by improving the expression of inflammatory genes such as COX-2, inhibiting negative remodeling promoted by MMP-9, increasing cell proliferation effect via EGF, and reducing cellular apoptosis by modulating caspase-3. A faster healing effect was evident in the first 7 days of treatment compared to 14 days of treatment, indicating the pharmacological potential of chrysin. Overall, these results demonstrate the potent effect of chrysin in the gastrointestinal tract and elucidate the genes involved in the healing of gastric ulcers. Moreover, an increase in the levels of gastric mucosa defensive factors is involved in the activity of chrysin in the gastric mucosa.

Chemical constituents and allelopathic activity of Machaerium eriocarpum Benth.

The analysis by HPLC-PDA of the hydroalcoholic extract of the leaves of M. eriocarpum together with the injection of the fractions containing the already identified metabolites allowed the detection of at least 5 flavonoids, of which two are derived from apigenin and three from luteolin. After isolating larger amounts of isovitexin (I), assays were performed to evaluate the allelopathic activity together with the crude extract. The results show that the initial inhibition indexes were very similar to those observed in the treatments with F17 (Fraction enriched in isovitexin) and F18 (isovitexin), mainly in the concentrations of 500 and 1000 mg L-1. The index of the number of lateral roots, an increase of the inhibitory effect is observed with the increase of the concentration of M. eriocarpum extract.

Byrsonima intermedia A. Juss partitions promote gastroprotection against peptic ulcers and improve healing through antioxidant and anti-inflammatory activities.

Byrsonima intermedia is a species of bush popularly used to treat gastrointestinal disorders, such as gastric ulcers, gastritis, and diarrhea. Previous studies have revealed that the methanolic crude extract of B. intermedia leaves has gastroprotective and healing properties. In this new study, we specifically investigated two purified partitions, ethyl acetate (EtOAc) and water (AcoAq), obtained from the crude extract to characterize the antiulcer effects of these two partitions and the mechanisms of action of this medicinal plant. The healing effects of these partitions on the gastric and duodenal mucosa were assessed after ischemia-reperfusion (I/R) or acetic acid-induced injury. The involvement of tumor necrosis factor-alpha (TNF-alpha), interleukin 1ß (IL-1ß), interleukin 10 (IL-10), and myeloperoxidase (MPO) activity and glutathione (GSH) levels were determined. The antibacterial activity against Helicobacter pylori was evaluated using microdilution methods. The phytochemical analysis of AcoAq revealed a predominance of oligomeric proanthocyanidins and galloyl quinic esters, whereas EtOAc was found to contain concentrated flavonoids. Both partitions led to a significant reduction in gastric lesions, but AcoAq was more effective than EtOAc with regard to anti-Helicobacter pylori activity in addition to protecting the gastric mucosa against ethanol, non-steroidal anti-inflammatory drugs (NSAIDs) and duodenal mucosal damage induced by cysteamine. Additionally, both partitions were associated with a significant increase in gastric and duodenal healing and increased gastric mucosal GSH content after damage induced by acetic acid. On the other hand, after 6 days of treatment, EtOAc was more effective than AcoAq in ameliorating gastric damage upon initiation of the gastric I/R, which was accompanied by a significant reduction in the activity of gastric mucosal MPO, IL 1-ß and TNF-alpha, as well as an elevation in IL-10 and GSH content. These results demonstrate that the oligomeric proanthocyanidins and galloyl quinic esters present in AcoAq were more effective in the prevention of gastric and duodenal ulcers due to the antioxidant effects of these compounds, whereas the flavonoids present in EtOAc were more effective due to their anti-inflammatory activity on the gastric and duodenal tissue. All these results confirm that the rich phytochemical diversity of B. intermedia contributes to the pharmacological actions of this medicinal plant on the gastrointestinal tract in addition to its activity against H. pylori.

Can the gastric healing effect of Eugenia punicifolia be the same in male and female rats?

ETHNOPHARMACOLOGICAL RELEVANCE: Eugenia punicifolia (Kunth) DC. (Myrtaceae), an Amazonian medicinal plant known as "pedra-ume-caá," is popularly used as a natural remedy for inflammation, wounds, infections, diabetes, fever, and flu. Its anti-inflammatory, antinociceptive, and gastroprotective effects have already been characterized. We evaluated the gastric healing effect of the hydroalcoholic extract of the leaves of E. punicifolia (HEEP) in male and female Wistar rats against nonsteroidal anti-inflammatory drugs (NSAIDs) and ethanol. MATERIALS AND METHODS: The healing effect of HEEP on the gastric mucosa of adult male and female Wistar rats was measured after the chronic application of aggressive factors such as NSAIDs or 80% ethanol. Male, and intact and ovariectomized (OVZ) female rats were treated with HEEP for two days (NSAIDs) or one, two, four, and six days (80% ethanol). The stomachs were analyzed macroscopically for ulcerative lesions (mm2), and the healing process was measured using biochemical analysis with anti-inflammatory and antioxidant parameters. RESULTS: Macroscopic evaluation of the gastric mucosa showed that gastric lesions induced by NSAIDs were significantly healed (66%) and pro-inflammatory interleukin 5 cytokine level was decreased after two-day oral treatment with HEEP compared with those in the negative control group (p < 0.05). However, the gastric lesions induced by NSAIDs did not heal in HEEP-treated female rats (p > 0.05). In addition, four-day treatment with HEEP significantly healed the gastric lesions induced by ethanol in male and female rats (63% and 78%, respectively) compared to those of the negative control group (p < 0.05). However, the OVZ group required six days of HEEP treatment to heal gastric ulcers (67% compared to the control group). HEEP exerts the healing effect against ethanol by significantly reducing neutrophil infiltration into the gastric mucosa by decreasing myeloperoxidase activity in male and OVZ rats after four and six days of treatment, respectively (p < 0.05). Four-day treatment with HEEP also increased the level of a non-enzymatic antioxidant, reduced glutathione in intact females compared to that of the negative control group (p < 0.05). CONCLUSION: These findings indicated that HEEP was effective in promoting the healing of gastric ulcers induced by NSAIDs or ethanol. The gastric healing effects of this extract could be affected by female sex hormone interference; in future, comprehensive studies should be performed by considering sex differences.

Sex-specific effects of Eugenia punicifolia extract on gastric ulcer healing in rats.

AIM: To evaluate the sex-specific effects of a hydroalcoholic extract from Eugenia punicifolia (HEEP) leaves on gastric ulcer healing. METHODS: In this rat study involving males, intact (cycling) females, and ovariectomized females, gastric ulcers were induced using acetic acid. A vehicle, lansoprazole, or HEEP was administered for 14 d after ulcer induction. Body weight was monitored throughout the treatment period. At the end of treatment, the rats were euthanized and the following in vivo and in vitro investigations were performed: macroscopic examination of the lesion area and organ weights, biochemical analysis, zymography, and evaluation of protein expression levels. Additionally, the concentration-dependent effect of HEEP was evaluated in terms of subacute toxicity and cytotoxicity. RESULTS: Compared to the vehicle, HEEP demonstrated a great healing capacity by substantially reducing the ulcerative lesion area in males (52.44%), intact females (85.22%), and ovariectomized females (65.47%), confirming that HEEP accelerates the healing of acetic acid-induced gastric lesions and suggesting that this effect is modulated by female sex hormones. The antiulcer effect of HEEP was mediated by prostaglandin E2 only in male rats. Overall, the beneficial effect of HEEP was the highest in intact females. Notably, HEEP promoted the expression of vascular endothelial growth factor (intact vs ovariectomized females) and decreased the expression of Caspase-8 and Bcl-2 (intact female vs male or ovariectomized female). Additionally, HEEP enhanced fibroblast proliferation and migration into a wounded area in vitro, confirming its healing effect. Finally, no sign of subacute toxicity or cytotoxicity of HEEP was observed. CONCLUSION: In gastric ulcers, HEEP-induced healing (modulated by female sex hormones; in males, mediated by prostaglandin) involves extracellular matrix remodeling, with gastric mucosa cell proliferation and migration.

Multielement analysis of plant extracts with potential use in the treatment of peptic ulcers by synchrotron radiation total reflection X-ray fluorescence.

Some plants popularly employed for the treatment of peptic ulcers have proved to be attractive sources of new drugs. Despite extensive research, the pharmacological and toxicological potentials of these plants are not fully understood. In this context, the aim of this work was to analyze the multielemental composition of the methanolic extracts of three of those plants, Alchornea glandulosa (AG), Davilla elliptica (DE) and Davilla nitida (DN), with the intention of contributing to the understanding of the mechanisms of action of these extracts. For this purpose, we used the analytical technique of total reflection X-ray fluorescence (TXRF) by synchrotron radiation at the Brazilian Synchrotron Light Source (LNLS/CNPEM). It was possible to determine the concentrations of the elements: P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Rb and Br in all of the samples. Selenium (Se) was detected only in the DN extract. An inverse relationship between the concentrations of elements with proven effectiveness and the gastroprotective activity of extracts considering induction protocols with ethanol and non-steroidal anti-inflammatory drugs (NSAIDs) was obtained. This data suggests that the function of the extract is not only associated with providing the elements for restoring the gastric mucosa but that it also promotes the displacement of these elements from other parts of the mucosa to the damaged area. Correlations between the concentrations of the elements were also obtained. In the DE extract, which is the most effective extract for both induction protocols, the obtained correlations were above 70% among almost all of the elements, and no anticorrelations were found. For the other two extracts, in the less effective extract (AG) anticorrelations above 70% were predominantly found. Meanwhile, in the DN extract, a few high anticorrelations were found, which may explain its intermediate stage of effectiveness.

Involvement of Opioid System, TRPM8, and ASIC Receptors in Antinociceptive Effect of Arrabidaea brachypoda (DC) Bureau.

Arrabidaea brachypoda (DC) Bureau is a medicinal plant found in Brazil. Known as "cipó-una", it is popularly used as a natural therapeutic agent against pain and inflammation. This study evaluated the chemical composition and antinociceptive activity of the dichloromethane fraction from the roots of A. brachypoda (DEAB) and its mechanism of action. The chemical composition was characterized by high-performance liquid chromatography, and this fraction is composed only of dimeric flavonoids. The antinociceptive effect was evaluated in formalin and hot plate tests after oral administration (10-100 mg/kg) in male Swiss mice. We also investigated the involvement of TRPV1 (transient receptor potential vanilloid 1), TRPA1 (transient receptor potential ankyrin 1), TRPM8 (transient receptor potential melastatin 8), and ASIC (acid-sensing ion channel), as well as the opioidergic, glutamatergic, and supraspinal pathways. Moreover, the nociceptive response was reduced (30 mg/kg) in the early and late phase of the formalin test. DEAB activity appears to involve the opioid system, TRPM8, and ASIC receptors, clearly showing that the DEAB alleviates acute pain in mice and suggesting the involvement of the TRPM8 and ASIC receptors and the opioid system in acute pain relief.

Anti-inflammatory intestinal activity of Combretum duarteanum Cambess. in trinitrobenzene sulfonic acid colitis model.

AIM: To evaluate the anti-inflammatory intestinal effect of the ethanolic extract (EtOHE) and hexane phase (HexP) obtained from the leaves of Combretum duarteanum (Cd). METHODS: Inflammatory bowel disease was induced using trinitrobenzenesulfonic acid in acute and relapsed ulcerative colitis in rat models. Damage scores, and biochemical, histological and immunohistochemical parameters were evaluated. RESULTS: Both Cd-EtOHE and Cd-HexP caused significant reductions in macroscopic lesion scores and ulcerative lesion areas. The vegetable samples inhibited myeloperoxidase increase, as well as pro-inflammatory cytokines TNF-α and IL-1ß. Anti-inflammatory cytokine IL-10 also increased in animals treated with the tested plant samples. The anti-inflammatory intestinal effect is related to decreased expression of cyclooxygenase-2, proliferating cell nuclear antigen, and an increase in superoxide dismutase. CONCLUSION: The data indicate anti-inflammatory intestinal activity. The effects may also involve participation of the antioxidant system and principal cytokines relating to inflammatory bowel disease.

Cissus sicyoides: Pharmacological Mechanisms Involved in the Anti-Inflammatory and Antidiarrheal Activities.

The objective of this study was to evaluate the pharmacological mechanisms involved in anti-inflammatory and antidiarrheal actions of hydroalcoholic extract obtained from the leaves of Cissus sicyoides (HECS). The anti-inflammatory effect was evaluated by oral administration of HECS against acute model of edema induced by xylene, and the mechanisms of action were analysed by involvement of arachidonic acid (AA) and prostaglandin E2 (PGE2). The antidiarrheal effect of HECS was observed and we analyzed the motility and accumulation of intestinal fluid. We also analyzed the antidiarrheal mechanisms of action of HECS by evaluating the role of the opioid receptor, α2 adrenergic receptor, muscarinic receptor, nitric oxide (NO) and PGE2. The oral administration of HECS inhibited the edema induced by xylene and AA and was also able to significantly decrease the levels of PGE2. The extract also exhibited significant anti-diarrheal activity by reducing motility and intestinal fluid accumulation. This extract significantly reduced intestinal transit stimulated by muscarinic agonist and intestinal secretion induced by PGE2. Our data demonstrate that the mechanism of action involved in the anti-inflammatory effect of HECS is related to PGE2. The antidiarrheal effect of this extract may be mediated by inhibition of contraction by acting on the intestinal smooth muscle and/or intestinal transit.

Ulcer healing and mechanism(s) of action involved in the gastroprotective activity of fractions obtained from Syngonanthus arthrotrichus and Syngonanthus bisulcatus.

BACKGROUND: Syngonanthus arthrotrichus and Syngonanthus bisulcatus, currently known for Comanthera aciphylla (Bong.) L.R.Parra & Giul. and Comanthera bisulcata (Koern.) L.R. Parra & Giul, popularly known in Brazil as "sempre-vivas," are plants from the family Eriocaulaceae. They are found in the states of Minas Gerais and Bahia. The species are known to be rich in flavonoids to which their gastroprotective activity has been attributed. In this research, experimental protocols were performed to elucidate the associated mechanisms of action. METHODS: The activity was evaluated using induced gastric ulcer models (acetic acid and ethanol-induced gastric lesions in NEM or L-NAME pre-treated mice, and by ischemia/reperfusion). Antioxidant enzymes, serum somatostatin, and gastrin were also evaluated. RESULTS: In chronic gastric ulcers, a single daily oral dose of Sa-FRF or Sb-FRF (100 mg/kg body wt.) for 14 consecutive days accelerated ulcer healing to an extent similar to that seen with an equal dose of cimetidine. The pre-treatment of mice with NEM (N-ethylmaleimide) or L-NAME (N-nitro-L-arginine) abolished the protective activity of Sa-FRF, Sa-FDF, Sb-FDF and Sb-FRF or Sa-FRF and Sb-FRF, respectively, which indicates that antioxidant compounds and nitric oxide synthase activity are involved in the gastroprotective. Sa-FRF and Sb-FRF (100 mg/kg p.o) protected the gastric mucosa against ulceration that was induced by ischemia/reperfusion (72 and 76 %, respectively). It also decreased lipid peroxidation and restored total thiols in the gastric wall of mice that had been treated with ethanol. When administered to rats submitted to ethanol-induced gastric lesions, Sa-FRF and Sb-FRF (100 mg/kg, p.o.) increased the somatostatin serum levels, while the gastrin serum levels were proportionally decreased. CONCLUSIONS: The results indicate significant healing effects and gastroprotective activity for the Sa-FRF and Sb-FRF, which probably involves the participation of SH groups, nitric oxide (NO), the antioxidant system, somatostatin, and gastrin. All are integral parts of the gastrointestinal mucosa's cytoprotective mechanisms against aggressive factors.

Effect of Himatanthus sucuuba in Maternal Reproductive Outcome and Fetal Anomaly Frequency in Rats.

The aim of this study was to evaluate the effect of Himatanthus sucuuba on the maternal reproductive outcome and fetal anomaly incidence in rats. Pregnant rats were randomly divided into three experimental groups as follows: Control = treated with water (vehicle), treated 250 = treated with H. sucuuba at dose 250 mg/kg, and treated 500 = treated with H. sucuuba at dose 500 mg/kg. The rats were orally treated, by gavage, with H. sucuuba or vehicle (water) during preimplantation and organogenic period (from gestational day 0-14). At day 21 of pregnancy, all rats were killed to obtain maternal-fetal data. The treatment with H. sucuuba at dose of 250 mg/kg caused reduction in placental efficiency and an increase preimplantation loss rate and placenta weight compared with the control. The treated 500 group presented a significant decrease in maternal weight gain, maternal weight gain minus gravid uterus weight, fetal weight, and placental efficiency compared with the control. In this group, there was a decrease in body weight at day 20 of pregnancy and metacarpus ossification and an increase in the preimplantation loss rate and skeletal anomalies compared with other groups. Himatanthus sucuuba extract caused intrauterine growth restriction, preimplantation loss, and developmental delay in the high doses tested.

Does the gastroprotective action of a medicinal plant ensure healing effects? An integrative study of the biological effects of Serjania marginata Casar. (Sapindaceae) in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Serjania marginata (Sapindaceae), a medicinal plant commonly found in the Brazilian Cerrado, Paraguay, Bolivia and Argentina, is also known as "cipó-uva" or "cipó-timbó". Ethnopharmacological studies indicate that the leaves from this medicinal plant are used in folk medicine to treat gastric pain. The overall objective of this study was to evaluate the gastroprotective and healing effect of the hydroalcoholic extract obtained from S. marginata (HESM) leaves using rodent experimental models. As part of the integrative study of this medicinal plant, we also evaluated the acute toxicity, antimicrobial, antidiarrheal, (anti)mutagenic, and hemodynamic effects. MATERIAL AND METHODS: We performed a pharmacological study to test the acute toxicity and antimutagenic effect (Ames assay) of the HESM. The HESM was tested against different necrosis-promoting agents and experimental manipulations, such as absolute ethanol, cysteamine, pyloric ligature, and ischemia-reperfusion (I/R) injury. The gastroprotective effect of the HESM was assessed by analyzing the gastric juice (volume, pH, total acidity) and the mucus in the gastric mucosa from rats. We assessed the levels of NO, sulfhydryl compounds, PGE2, vanilloid receptor, glutathione (GSH), and malondialdehyde (MDA), as well as the myeloperoxidase (MPO) activity. The gastric healing effects of the HESM were evaluated during 7 or 14 days of treatment. The intestinal motility, antidiarrheal action, and antibacterial effects (microdilution methods) of the HESM were also evaluated. RESULTS: The phytochemical analysis of the HESM revealed the presence of saponins, flavonoid glycosides, and tannins. The extract exhibited no sign of acute toxicity or mutagenic effect in vitro. In contrast, this extract exhibited a protective effect against the mutagenic action of direct- and indirect-acting mutagens. Only the oral administration of HESM (250mg/kg) significantly decreased the severity of gastric damage induced by ethanol (60.13%) and I/R (58.31%). The HESM exerts its gastroprotective effects by decreasing the MPO and MDA activities in the gastric tissue and by increasing the amount of adherent mucus covering the gastric mucosa. In vitro, the extract also displayed evident antimicrobial effects against Helicobacter pylori. However, the preventive effect of the HESM was not accompanied by an ulcer-healing effect. The treatment with HESM (14 days) significantly increased gastric lesions in 99% of the tested animals compared with the control group. This result represents a highly relevant piece of evidence that should resonate as an alert against the chronic use of this medicinal plant as an antiulcer in folk medicine. CONCLUSIONS: Despite the anti-H. pylori and gastroprotective actions of S. marginata in experimental models, the gastric injuries aggravation induced after chronic treatment with the HESM argues against the use of this plant species in folk medicine.

The Anti-Inflammatory Effects of the Methanolic Extract and Fractions from Davilla elliptica St. Hil. (Dilleniaceae) on Bothrops jararaca Envenomation.

Inflammation and haemorrhage are the main characteristics of tissue injury in botropic envenomation. Although some studies have shown that anti-venom prevents systemic reactions, it is not efficient in preventing tissue injury at the site of the bite. Therefore, this work was undertaken to investigate the anti-inflammatory effects of the methanolic extract and fractions from D. elliptica and to evaluate the role of matrix metalloproteinases (MMPs) in this process. Effects of the extract and fractions from D. elliptica were evaluated using a carrageenan-induced paw oedema model in rats, and leukocyte rolling was visualized by intravital. The quantification of MMPs activities (MMP-2 and MMP-9) extracted from the dermis of mice treated with extract and fractions alone or incubated with venom was determined by zymographic analyses. Our results show that intraperitoneal (i.p.) injection of fractions significantly reduced paw oedema after the carrageenan challenge. Treatment with the tannins fraction also resulted in considerable inhibition of the rolling of leukocytes and this fraction was able to decrease the activation of MMP-9. These results confirmed the anti-inflammatory activity of the methanolic extract and tannins fraction of D. elliptica and showed that the dermonecrosis properties of B. jararaca venom might be mediated through the inhibition of MMP-9 activity.

New steroidal saponin and antiulcer activity from Solanum paniculatum L.

Solanum paniculatum L. (Solanaceae) is a plant species widespread throughout tropical America, especially in the Brazilian Savanna region. It is used in Brazil for culinary purposes and in folk medicine to treat liver and gastric dysfunctions, as well as hangovers. Fractionation of the ethanolic extracts (70%) from aerial parts (leaves and twigs) of S. paniculatum led to the isolation of the two new saponins (22R, 23S, 25R)-3ß, 6α, 23-trihydroxy-5α-spirostane 6-O-ß-D-xylopyranosyl-(1"" → 3"')-O-[ß-D-quinovopyranosyl(1″' → 2')]-O-[α-L-rhamnopyranosyl(1" → 3')]-O-ß-D-quinovopyranoside (1) and diosgenin 3-O-ß-D-glucopyranosyl(1" → 6')-O-ß-D-glucopyranoside (2) together with four know compounds: caffeic acid (3), diosgenin ß-D-glucopyranoside (4), rutin (5), and quercetin 3-O-α-L-rhamnopyranosyl (1"' → 6 ″)-O-ß-D-galactopyranoside (6). The structures of these compounds were elucidated by extensive use of 1D and 2D NMR experiments along with HRESIMS analyses. Different doses (31.25-500 mg/kg) of ethanolic extract of leaves from S. paniculatum were evaluated against gastric ulcer induced by ethanol in rats. The lower dose of extract able to promote antiulcer effect was 125 mg/kg. The treatment with S. paniculatum by oral route was able to decrease gastric lesion area and also reduced levels of myeloperoxidase (MPO) in the gastric mucosa. Our results reveal for the first time, steroidal saponins from S. paniculatum and the antiulcer effect of this species at this lower dose.

Geraniol-a flavoring agent with multifunctional effects in protecting the gastric and duodenal mucosa.

Geraniol is an acyclic monoterpene alcohol commonly used as a flavoring agent. The present study was undertaken to investigate antiulcerogenic effects of geraniol and to determine the possible mechanisms involved in this action. In the model of the ethanol-induced ulcer, treatment of rats with geraniol by oral route significantly inhibited gastric lesions by 70 % (7.50 mg/kg) to 99 % (200 mg/kg). Analysis of the gastric tissue of rats treated with geraniol (7.50 mg/kg) revealed that total glutathione content levels (GSH) increased and levels of myeloperoxidase (MPO) decreased in the gastric mucosa. Oral treatment with geraniol significantly decreased the number of ulcerative lesions induced by ischemia/reperfusion injury by 71 % and the duodenal ulcers induced by cysteamine by 68 %. The action of geraniol was mediated by the activation of defensive mucosa-protective factors such as the nitric oxide (NO) pathway, endogenous prostaglandins, increased mucus production, increased sulfhydryl compounds, antioxidant properties and the stimulation of calcitonin gene-related peptide (CGRP) release through the activation of transient receptor potential vanilloid (TRPV). The multifaceted gastroprotective mechanisms of geraniol represent a promising option for the treatment of gastric and duodenal mucosa injury.