Effects of Tithonia diversifolia (Asteraceae) extract on innate inflammatory responses.

ETHNOPHARMACOLOGICAL RELEVANCE: Tithonia diversifolia (Helms.) A. Gray, popularly known in Brazil as "margaridão" or "mão-de-Deus" has been used in the folk medicine as anti-inflammatory and against other illnesses in several countries. Indeed, many studies show de effect of T. diversifolia in the inflammatory process, however, any of them have demonstrated the mechanism of cell migration. AIM OF THE STUDY: The aim of this investigation was to show the in vivo and in vitro effects of T. diversifolia leaves ethanol extract on neutrophil trafficking from the blood to the inflamed tissue and on cell-derived secretion of chemical mediators, as well as, the effects on inflammatory resolution and inflammatory pain. MATERIALS AND METHODS: Anti-inflammatory activity was investigated using carrageenan-induced inflammation in the subcutaneous tissue of male Swiss mice orally treated with the T. diversifolia extract (0.1, 1 or 3 mg/kg). The leukocyte influx (optical microscopy) and the secretion of chemical mediators (TNF, IL-6, IL-1ß and CXCL1, by enzyme-linked immunosorbent assay) were quantified in the inflamed exudate. Histological analysis of the pouches was performed. N-Formyl-methionine-leucine-phenylalanine-induced chemotaxis, lipopolysaccharide-induced TNF, IL-6, IL-1ß, CXCL1 and NO production, and adhesion molecule expression (CD62L and CD18, flow cytometry) were in vitro quantified using oyster glycogen recruited peritoneal neutrophils previous treated with the extract (1, 10, or 100 µg/mL). The resolution of inflammation was accessed by efferocytosis assay, and the antinociceptive activity was investigated using carrageenan-induced mechanical hypersensitivity. RESULTS: The oral treatment with T. diversifolia promoted reduction in the neutrophil migration as well as the decrease in total protein, TNF, IL-1ß and CXCL1 levels in the inflamed exudate. In vitro treatment with T. diversifolia shedding of ß2 integrin expressions, without alter CD62L expression. The extract was able to increase the efferocytosis of apoptotic neutrophils, and the increase of the IL-10 and the decrease of TNF secretion. Additionally, the extract reduced the hypersensitivity induced by carrageenan. CONCLUSIONS: Together, the data herein obtained showed that T. diversifolia extract presented anti-inflammatory activity by inhibiting the cytokine and NO production, and also the leukocyte migration. The mechanisms involved in the extract anti-inflammatory effects include the impairment in the leukocyte migration to the inflamed tissue, the pro-resolution activity, and consequently the anti-hypersensitivity.

Ipomoea pes-caprae (L.) R. Br (Convolvulaceae) relieved nociception and inflammation in mice - A topical herbal medicine against effects due to cnidarian venom-skin contact.

ETHNOPHARMACOLOGICAL RELEVANCE: Ipomoea pes-caprae is known as bayhops, beach morning glory or goat's foot, and in Brazil as salsa-de-praia. Its leaves are used in worldwide folk medicine for the relief of jellyfish-stings symptoms. The literature only reports the neutralizing effects of nonpolar plant derived over jellyfish venoms, without validating the popular use or exploring the mechanism of action. AIM OF THE STUDY: This study aimed to evaluate and validate the topical effects of a semisolid containing hydroethanolic extract obtained from the aerial parts of I. pes-caprae using different models of paw- and ear-oedema and spontaneous nociception in mice, attempting to better understand the mechanism involved in its effect. MATERIALS AND METHODS: Leaf and stem of I. pes-caprae were extracted by ethanol 50% (v/v) and the soft-extract was incorporated in Hostacerin® cream base at 0.5%, 1.0% and 2% (w/w). The anti-hypersensitivity effects were evaluated by injecting the Physalia physalis venom into the right mice's hindpaw pre-treated either with the semisolid containing the I. pes-caprae extract or with the isolated majority compound 3,5-Di-O-caffeoylquinic acid (ISA). The topical anti-inflammatory activity was investigated using both preclinical models: paw oedema induced by trypsin, bradykinin (BK), histamine and carrageenan, and ear oedema induced by capsaicin. Additionally, the model of spontaneous nociception induced by trypsin and capsaicin were used to verify the topical antinociceptive activity. RESULTS: The animals pre-treated with the semisolid containing I. pes-caprae extract or with the intraplantar injection of the major component (ISA) had the mechanical hypersensitivity induced by P. physalis venom significantly reduced. Significant inhibition was also observed in paw-oedema induced by trypsin, histamine and BK, and in a less extent in carrageenan-induced paw oedema. Similar effect was observed in mice challenged to the capsaicin-induced ear-oedema. Besides the vascular effects, the extract interfered with leukocyte migration induced by histamine injection. Finally, the semisolid presented significant inhibition in trypsin- and capsaicin-induced spontaneous nociception. CONCLUSIONS: The hydroethanolic extract of I. pes-caprae showed compliance with the topical popular use of the herbal product to relieve the symptoms evoked by the cnidarian venom-skin contact, such as neurogenic oedema and nociception. The extract components seem to interfere with the effects resulting from the TRPV1, B2R and PAR-2 activation, once it interfered with painful-behaviour and oedema induced by capsaicin, BK and trypsin, pointing the histaminergic system as the main target, once it is an important mediator in the signalling pathway of the aforementioned receptors.

Topical anti-inflammatory activity of semisolid containing standardized Aleurites moluccana L. Willd (Euphorbiaceae) leaves extract.

ETHNOPHARMMACOLOGICAL RELEVANCE: Aleurites moluccana is a medicinal plant popularly used to treat pain, fever, asthma, hepatitis, gastric ulcer and inflammatory process in general. Recently, pre-clinical studies have demonstrated that the dry extract obtained from A. moluccana leaves was effective as analgesic, anti-inflammatory and wound healing. AIM: The present study has aimed to evaluate the mechanisms involved in the topical anti-inflammatory effects of the semisolid containing 10mg/g of A. moluccana dried extract. MATERIAL AND METHODS: Ear edema induced by croton oil (2.5%) in mice was used throughout the study. The level of cytokines tumour necrosis factor (TNF) and interleukine-1ß (IL-1ß) and chemokine keratinocyte chemoattractant (CXCL1/KC), and neutrophil migration were quantified. The histological analysis has also been performed. RESULTS: The topical treatment with the semisolid was able to significantly inhibite the ear edema (35.77±7.35%). This effect was accompanied by the reduction of leukocyte migration, as well as TNF (53.75±12.96%), IL-1ß (38.36±5.92%), and CXCL1/KC (62.29±11.65%) decreased levels. CONCLUSIONS: This study demonstrated for the first time the mechanisms involved in the topical anti-inflammatory effect presented by the semisolid containing A. moluccana dried extract pointing as the main mechanism is the reduction in the leukocyte migration and consequently resulting in diminished levels of cytokins and chemokines, indicating this herbal product as a promissor anti-inflammatory phytomedicine to treat skin inflammatory diseases.

Bioactive metabolites from Cnidoscolus souzae and Acmella pilosa.

The bioassay-guided purification of the ethanol extracts of Acmella pilosa and Cnidoscolus souzae, two plants of the native flora of the Yucatan Peninsula used in traditional medicine to treat inflammation and pain, resulted in the identification of rosmarinic acid (1) and caffeic acid (2) as the bioactive metabolites from A. pilosa, and of 7-deoxynimbidiol (4) as the major bioactive metabolite from C. souzae. Metabolites 1, 2, and 4 proved to be responsible for the antioxidant activity originally detected in the corresponding organic crude extracts; 7-deoxynimbidiol (4) showed good analgesic and anti-inflammatory activities, inhibiting the pain induced by PGE2 and reducing the edema induced by carrageenan, respectively.