Antinociceptive and anti-inflammatory activities of Copaifera pubiflora Benth oleoresin and its major metabolite ent-hardwickiic acid.

ETHNOPHARMACOLOGICAL RELEVANCE: Copaifera species folkloric names are "copaíbas, copaibeiras, copaívas or oil stick", which are widely used in Brazilian folk medicine. Among all ethnopharmacological applications described for Copaifera spp oleoresins, their anti-inflammatory effect stands out. However, the knowledge of anti-inflammatory and antinociceptive properties of Copaifera pubiflora Benth is scarce. AIM OF THE STUDY: To investigate the cytotoxic, anti-inflammatory, and antinociceptive activities of C. pubiflora oleoresin (CPO), and its major compound ent-hardwickiic acid (HA). MATERIAL AND METHODS: The phosphatase assay was used to evaluate the cytotoxicity of CPO and HA in three different cell lines. CPO and HA doses of 1, 3, and 10 mg/kg were employed in the biological assays. The assessment of motor activity was performed using open-field and rotarod tests. Anti-inflammatory activity of CPO and HA was assessed through luciferase assay, measurement of INF-γ, IL-1ß, IL-6, IL-10, and TNF-α in a multi-spot system with the immortalized cell line THP-1, zymosan-induced arthritis, and carrageenan-induced paw edema. Acetic acid-induced abdominal writhing and formalin tests were undertaken to evaluate the antinociceptive potential of CPO and HA. In addition, the evaluation using carrageenan was performed to investigate the effect of CPO in pain intensity to a mechanical stimulus (mechanical hyperalgesia), using the von Frey filaments. A tail-flick test was used to evaluate possible central CPO and HA actions. RESULTS: In the cytotoxicity evaluation, CPO and HA were not cytotoxic to the cell lines tested. CPO and HA (10 mg/kg) did not affect animals' locomotor capacity in both open-field and rotarod tests. In the luciferase assay, CPO and HA significantly reduced luciferase activity (p < 0.05). This reduction indicates a decrease in NF-κB activity. HA and CPO decreased INF-γ, IL-1ß, IL-6, IL-10, and TNF-α at 24 and 72 h in the multi-spot system. In zymosan-induced arthritis, CPO and HA decreased the number of neutrophils in the joint of arthritic mice and the number of total leukocytes (p < 0.05). In experimental arthritis HA significantly decreased joint swelling (p < 0.05). CPO and HA also increased the mechanical threshold during experimental arthritis. HA and CPO significantly inhibited the carrageenan-induced paw edema, being the doses of 10 mg/kg the most effective, registering maximum inhibitions of 58 ± 8% and 76 ± 6% respectively, p < 0.05. CPO and HA reduced the nociceptive behavior in both phases of formalin at all tested doses. The highest doses tested displayed inhibitions of 87 ± 1% and 72 ± 4%, respectively, p < 0.001, in the first phase, and 87 ± 1% and 81 ± 2%, respectively, p < 0.001, in the second phase. Oral treatment of CPO and HA (1, 3, 10 mg/kg) significantly reduced the nociceptive response in acetic acid-induced abdominal writhings, and the 10 mg/kg dose was the most effective with maximum inhibitions of 86 ± 2% and 82 ± 1%, respectively, p < 0.001. Both HA and CPO significantly decreased the intensity of mechanical inflammatory hyper-nociception on carrageenan-induced hyperalgesia at all tested doses, and 10 mg/kg was the most effective dose with maximum inhibitions of 73 ± 5% and 74 ± 7%, respectively, p < 0.05.CPO increased the tail-flick latencies in mice, and concomitant administration of naloxone partially reduced its effect. CONCLUSIONS: CPO and HA may inhibit the production of inflammatory cytokines by suppressing the NF-κB signaling pathway, resulting in anti-inflammatory and antinociceptive activities.

Bauhinia forficata link, a Brazilian medicinal plant traditionally used to treat cardiovascular disorders, exerts endothelium-dependent and independent vasorelaxation in thoracic aorta of normotensive and hypertensive rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Bauhinia forficata Link, commonly known as "cow's paw", is a native plant from South America. Its leaves are widely used in Brazilian folk medicine to treat diabetes and cardiovascular disorders. Although this species' biological potential has been extensively proven as an antidiabetic, anti-inflammatory and antioxidant agent, there is a lack of studies to evidence its action on the cardiovascular system. AIM OF THE STUDY: This study was designed to investigate the vascular effects of B. forficata leaves preparations and its majority compound kaempferitrin, as well as its aglycone form kaempferol, in rat aortic rings of normotensive (NTR) and hypertensive (SHR) rats. MATERIALS AND METHODS: Aorta rings from NTR and SHR precontracted with phenylephrine were exposed to cumulative concentrations of B. forficata extract, fractions (1-50 µg/mL) and compounds (0.001-0.3 µg/mL). The mechanisms involved in the vasorelaxant effect of ethyl-acetate plus butanol fraction (EAButF) were also evaluated. RESULTS: Although kaempferitrin is the most abundant compound found in both methanolic extract and EAButF, 24 minor phenolic compounds were identified in B. forficata leaves, including kaempferol. EAButF was the only with endothelium-dependent and independent vasorelaxant properties in both NTR and SHR. The incubation with L-NAME or ODQ completely blocked EAButF-induced vasorelaxation. On the other hand, the incubation with propranolol, atropine, indomethacin, glibenclamide or barium chloride did not change the vasorelaxant activity of EAButF (50 µg/mL). Nevertheless, the incubation with tetraethylammonium and 4-aminopyridine significantly influenced the EAButF activity. It was also shown that Ca2+ influx or efflux is not related to EAButF vasorelaxation potential. Kaempferitrin and kaempferol were also able to relax the rat aortic rings in 34.70% and 40.54%, respectively. CONCLUSIONS: This study shows, for the first time, the vasorelaxant effect of EAButF from B. forficata leaves, an effect that may be attributed to the modulation of vascular tone through nitric oxide/soluble guanylate cyclase pathway, and potassium channels. The bioactive kaempferitrin and kaempferol seem to be important for the effects observed with the fraction. Finally, preparations obtained from the leaves of B. forficata may be interesting candidates for new or complementary strategies regarding cardiovascular diseases.

Flavonoid-rich fraction of Bauhinia forficata Link leaves prevents the intestinal toxic effects of irinotecan chemotherapy in IEC-6 cells and in mice.

This study evaluated the effects of flavonoid-rich fraction from Bauhinia forficata leaves (FRF-BF), against intestinal toxicity induced by irinotecan. The leaves of this plant are used like tea in Brazilian folk medicine, and it is rich in flavonoids, mainly kaempferitrin. First, the chemopreventive effects of FRF-BF and kaempferitrin were evaluated in intestinal cells (IEC-6 cells) exposed to irinotecan. Next, the effects were evaluated against irinotecan-induced mucositis in mice. Lastly, melanoma was induced in C57BL/6 mice to evaluate FRF-BF interference on irinotecan antitumor activity. The results showed that FRF-BF and kaempferitrin exert no cytotoxic effects in IEC-6 cells and confirmed that pretreatment with FRF-BF and kaempferitrin displays chemoprotective effects against cytotoxicity induced by irinotecan. Interestingly, the FRF-BF (100 mg/kg, p.o) reduced the intestinal motility in mice and attenuated parameters linked to irinotecan-induced intestinal mucositis, including diarrhea, histological damage, depletion of duodenal GSH, amount of TNF-α, and MPO activity in the small intestine. Also, FRF-BF does not interfere in the antitumor activity of irinotecan and exerted antitumoral activity in murine melanoma. In conclusion, FRF-BF (100 mg/kg, p.o) presents promising pharmacological potential to prevent and attenuate the severity of intestinal mucositis during chemotherapy treatment, related to the presence of kaempferitrin.

Hydroalcoholic Extract from Inflorescences of Achyrocline satureioides (Compositae) Ameliorates Dextran Sulphate Sodium-Induced Colitis in Mice by Attenuation in the Production of Inflammatory Cytokines and Oxidative Mediators.

Achyrocline satureioides is a South American herb used to treat inflammatory and gastrointestinal diseases. This study evaluated intestinal anti-inflammatory effects of the hydroalcoholic extract of inflorescences of satureioides (HEAS) in dextran sulfate sodium (DSS) induced colitis in mice. Mice were orally treated with vehicle, 5-aminosalicylic acid (100 mg/kg), or HEAS (1-100 mg/kg). Clinical signs of colitis and colonic histopathological parameters were evaluated, along with the determination of levels of reduced glutathione and lipid hydroperoxide (LOOH), the superoxide dismutase (SOD), and myeloperoxidase (MPO) activity in colon. The colonic content of cytokines (TNF, IL-4, IL-6, and IL-10) was measured. Additionally, the effects of the extract on nitric oxide (NO) release by lipopolysaccharide (LPS) stimulated macrophages and diphenylpicrylhydrazyl levels were determined. Mucin levels and SOD activity, as well as the LOOH, MPO, TNF, and IL-6 accumulation in colon tissues, were normalized by the HEAS administration. In addition, the extract elicited an increase in IL-4 and IL-10 levels in colon. NO release by macrophages was inhibited by HEAS and its scavenger activity was confirmed. Together these results suggest that preparations obtained from inflorescences from A. satureioides could be used in treatment for IBD. Besides, this work corroborates the popular use of A. satureioides in inflammatory disorders.

Gastroprotective bio-guiding study of fruits from Mimusops balata.

Mimusops spp. is used as plant-based antiulcer drugs in Indian traditional medicine. In this study, a bio-guiding study of methanolic extracts of Mimusops balata edible fruits was performed to identify an antiulcer gastric compound. The gastric lesions induced by HCl/ethanol in mice were significantly improved by methanolic extract from seed (MESe, 300 mg/kg), but not by methanolic extract from peel (MEPe, 300 mg/kg) or pulp (MEPu, 300 mg/kg), when compared to the vehicle group. Treatment with MESe also decreased gastric ulceration induced by indomethacin. The antiulcerogenic activity of MESe appears to involve the maintainance of GSH levels, reduction of LPO content, inhibition of neutrophil migration (as evidenced by a decrease in the MPO activity) and a potent free radical scavenger activity (IC50 = 3.4 µg/ml). Moreover, MESe decrease the gastric volume, pH, total acidity, and pepsin activity in the gastric juice. Exceptionally, MESe showed a high content of phenolic compound, identified by layer chromatography and Folin-Ciocalteu reagent. Considering the better pharmacological and phytochemical profile, MESe was successively partitioned and resulted in isolation and identification of a constituent, the flavonoid taxifolin, identified by spectroscopic methods ((1)H, (13)C NMR, and HPLC). Taxifolin also inhibited the ulcerogenic effect of HCl/ethanol at a low dose of 1.14 mg/kg and inhibited in vitro H+/K(+)-ATPase activity by 41% at a concentration of 100 µg/ml. Taken together, these results evidenced the gastroprotective potential of fruits from M. balata and showed that this effect is exclusive to the seeds.

Role of gastric mucus secretion, oxinitrergic system and sulfhydryl groups on the gastroprotection elicited by Polygala cyparissias (Polygalaceae) in mice.

OBJECTIVES: This study has aimed to assess the mechanisms of action for the gastroprotective effect of the acetone extract (PCAE) and methanol fraction (PCMF) of Polygala cyparissias, as well as to evaluate the activity of 1,3,6,8-tetrahydroxy-2,7-dimethoxyxanthone (1), 1,7-dihydroxy-2,3-dimethoxyxanthone (2) and astragalin (3). METHODS: Gastric secretion and mucus content were determined by pylorus ligation in mice. Nitric oxide (NO) and sulfhydryl group participation were observed by the pretreatment of mice with L-NAME or NEM. Acute ulcer was induced by ethanol/HCl and chronic ulcer by acetic acid. Anti-Helicobacter pylori activity was evaluated by the agar solid dilution assay. KEY FINDINGS: Neither PCAE nor PCMF had the ability to reduce H(+) concentration. However, both of them enhanced mucus secretion. PCAE demonstrated its gastroprotection in a NO-dependent manner, while PCMF exerted the activity depending on the sulfhydryl group. In chronic ulcer, the curative ratios for the PCAE and PCMF were 67.5 and 58.4%, respectively. No effect over H. pylori was detected. Compounds 1, 2 and 3 were able to reduce lesions in the order of 79.6, 73.8 and 67.6%, respectively. CONCLUSIONS: The data suggested that PCAE and PCMF displayed antiulcer activity due to different mechanisms and with the participation of phenolic compounds obtained from the plant.

Antiulcerogenic effect of Croton urucurana Baillon bark.

ETHNOPHARMACOLOGICAL RELEVANCE: Croton urucurana (Euphorbiaceae) bark is used to treat gastric ulcers. However, to our knowledge, no study has been conducted to confirm this therapeutic property. AIM OF THE STUDY: To evaluate the antiulcerogenic effect and any possible toxic effects of Croton urucurana bark in an induced gastric ulcer model in rats. MATERIALS AND METHODS: The preventive and healing properties of Croton urucurana bark methanol extract (CUE) were evaluated in experimental models of acute (ethanol and indomethacin) and chronic (acetic acid) gastric ulcers. The gastric juice and mucous were evaluated using the pylorus ligation model, while the gastroprotective action of sulphydryl compounds and nitric oxide were analysed using the ethanol model. The toxicity was evaluated with acute and subacute toxicity tests. RESULTS: No signs of toxicity were observed in the parameters analysed. All of the CUE doses tested (50, 100 and 250mg/kg) significantly reduced the gastric lesions by 70.25, 95.40 and 98.71%, respectively. Treatment with 30mg/kg lansoprazole (positive control) inhibited 82.58% of the gastric lesions. In the indomethacin model, the 50, 100 and 250mg/kg doses of CUE significantly reduced gastric damage by 67.85, 82.50 and 71.01%, respectively, and the positive control, cimetidine (200mg/kg), reduced gastric damage by 91.02%. The CUE (100mg/kg) and cimetidine (200mg/kg) treatments significantly reduced the ulcerative pathology induced by acetic acid, promoting 81.55 and 72.62% healing, respectively. Nitric oxide did not change the cytoprotection generated by CUE. However, the antiulcerogenic activity of CUE appears to involve sulphydryl compounds because CUE activity was inhibited in animals receiving a sulphydryl compound blocker. In addition, CUE exhibited systemic effects, increasing mucous production and decreasing gastric acidity. CONCLUSIONS: The present study shows that Croton urucurana bark exerts gastroprotective activity in rats without causing toxicity. This effect appears to involve sulphydryl compounds, increasing mucus production and reducing gastric acidity.

Gastroprotective activity of methanol extract and marrubiin obtained from leaves of Marrubium vulgare L. (Lamiaceae).

OBJECTIVES: The purpose of this study was to assess the gastroprotective properties of the methanol extract and the diterpene marrubiin obtained from the leaves of M. vulgare. METHODS: Assays were performed using different protocols in mice. Studies focusing on mechanisms of gastroprotection were also undertaken. KEY FINDINGS: In the model of ethanol-induced ulcers, we observed a significant reduction in all the parameters analysed; the curative ratios obtained were 49.31±0.57, 74.31±0.91 and 79.86±0.59 for the groups treated with 50 and 100mg/kg of extract of M. vulgare and omeprazole (30mg/kg), respectively. For indomethacin-induced ulcers, the percentages of ulcer inhibition were 50.32±5.60, 66.24±4.30, 82.17±04.09 and 67.52±4.38, for the groups treated with 25, 50 and 100mg/kg M. vulgare and positive control (cimetidine), respectively. In both models, the marrubiin (25mg/kg) produced a significant reduction in all the parameters when compared with the control group (P<0.01). There was also a significant increase in pH and mucus production in the groups treated with M. vulgare extract and marubiin. The results also demonstrated that the gastroprotection induced by the extract and marubiin is related to the activity of nitric oxide and endogenous sulfhydryls, which are important gastroprotective factors. CONCLUSIONS: The results of this study show that the extract of M. vulgare and marrubiin displays antiulcer activity and that this effect can be partly attributed to the isolated diterpene.