The Effect of Schinus terebinthifolius Raddi (Anacardiaceae) Bark Extract on Histamine-Induced Paw Edema and Ileum Smooth Muscle Contraction.

Schinus terebinthifolius Raddi (Anacardiaceae), popularly known as red aroeira, is used in traditional medicine to treat inflammatory, gastric, and respiratory disorders. The aim of this study was to evaluate the antihistaminic activity of S. terebinthifolius (St) bark extract by using in vivo and in vitro experimental models. The effects of St were investigated on contractions induced by histamine, carbachol, and potassium chloride in isolated guinea pig ileum. St was also studied in response to hind paw edema induced by histamine in rats. Experiments revealed that although St (250, 500, and 1,000 µg/mL) reduced the histamine-induced contractions by 9.1 ± 1.8, 50.2 ± 2.0, and 68.9 ± 2.0%, respectively, it did not inhibit contractions induced by carbachol or KCl. The association of St (250 and 500 µg/mL) with hydroxyzine, an H1-antihistamine (0.125 and 0.250 µM), increased the inhibitory effect to 67.0 ± 3.2 and 85.1 ± 2.1%, respectively. Moreover, St (100, 200, and 400 mg/kg) decreased paw edema from its peak by 33.9, 48.4, and 54.8%, respectively, whereas hydroxyzine (70 mg/kg) inhibited the peak edema by 56.5%. Altogether, the results suggest that the bark extract of S. terebinthifolius has an antihistaminic effect (H1).

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.

Antidiarrheal and intestinal antiinflammatory activities of a methanolic extract of Qualea parviflora Mart. in experimental models.

ETHNOPHARMACOLOGICAL RELEVANCE: An ethnopharmacological survey indicated that the bark from Qualea parviflora Mart. (Vochysiaceae) could be used to treat gastrointestinal disorders, such as diarrhea and intestinal inflammation. The objective of this study was to evaluate the effects of a methanolic extract from the bark of Qualea parviflora (QP) in an experimental model of diarrhea and intestinal inflammation induced in rodents. MATERIAL AND METHODS: The antidiarrheal and antispasmodic effects of QP were investigated by measuring intestinal motility, diarrhea, and intestinal fluid accumulation in rodents after challenging with a cathartic agent. In addition, the effects of QP on the contractility of the isolated mice-ileum preparation were determined. Acute intestinal inflammation was induced in male Wistar rats by the rectal administration of trinitrobenzenesulfonic acid (TNBS) in 50% ethanol (0.25 mL). QP was administered orally (for 5 days) prior to the induction of inflammation. The colonic injury and extent of inflammation were assessed by macroscopic damage scores and lesion length. The enhanced colonic mucosal injury, inflammatory response, and oxidative stress were evaluated by myeloperoxidase (MPO) activity; the tumor necrosis factor alpha (TNF-α), interleukin 1ß (IL1-ß), and malondialdehyde (MDA) levels; and the glutathione (GSH) content. RESULTS: Oral treatment with QP (500 mg/kg) delayed the onset of diarrhea, reduced the amount of liquid stool, and decreased the severity of the diarrhea and the evacuation index in rodents challenged with castor oil (p<0.01). Additionally, QP (150-500 µg/mL) demonstrated effective antispasmodic activity against carbachol-induced contractions of mouse ileum in vitro. Oral treatment (25 and 50 mg/kg/day) with QP significantly reduced the intestinal inflammation induced by TNBS in rats (52% and 45%, respectively). Improvement of colonic mucosal injury by treatment with QP was demonstrated by a decrease in MDA levels and an increase in GSH content in colonic tissue. QP also prevented intestinal inflammation as evidenced by reduced cytokine levels (TNF-α and IL1-ß) and low MPO activity. CONCLUSIONS: The ethnopharmacological usefulness of the bark from Qualea parviflora against diarrhea containing blood and mucus was supported by the observed antidiarrheal, antispasmodic, and intestinal antiinflammatory properties of this medicinal plant.