Daniel Augusto Gasparin Bueno Mendes

Ethanolic extract of roots from Arctium lappa L. accelerates the healing of acetic acid-induced gastric ulcer in rats: Involvement of the antioxidant system

We evaluate the curative efficacy of the ethanolic extract (EET) of roots from Arctium lappa (bardana) in healing of chronic gastric ulcers induced by 80% acetic acid in rats and additionally studies the possible mechanisms underlying this action. Oral administration of EET (1, 3, 10 and 30mg/kg) reduced the gastric lesion area in 29.2%, 41.4%, 59.3% and 38.5%, respectively, and at 10mg/kg promoted significant regeneration of the gastric mucosa, which was confirmed by proliferating cell nuclear antigen immunohistochemistry. EET (10mg/kg) treatment did not increase the gastric mucus content but restored the superoxide dismutase activity, prevented the reduction of glutathione levels, reduced lipid hydroperoxides levels, inhibited the myeloperoxidase activity and reduced the microvascular permeability. In addition, EET reduced the free radical generation and increased scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals in vitro. Furthermore, intraduodenal EET (10 and 30mg/kg) decreased volume and acidity of gastric secretion. Total phenolic compounds were high in EET (Folin-Ciocalteau assay) and the analysis by liquid chromatography-mass spectrometry revealed that the main compounds present in EET were a serie of hydroxycinnamoylquinic acid isomers. In conclusion, these data reveal that EET promotes regeneration of damaged gastric mucosa, probably through its antisecretory and antioxidative mechanisms.

Analysis of the Potential Topical Anti-Inflammatory Activity of Averrhoa carambola L. in Mice

Inflammatory skin disorders, such as psoriasis and atopic dermatitis, are very common in the population; however, the treatments currently available are not well tolerated and are often ineffective. Averrhoa carambola L. (Oxalidaceae) is an Asian tree that has been used in traditional folk medicine in the treatment of several skin disorders. The present study evaluates the topical anti-inflammatory effects of the crude ethanolic extract of A. carambola leaves, its hexane, ethyl acetate, and butanol fractions and two isolated flavonoids on skin inflammation. Anti-inflammatory activity was measured using a croton oil-induced ear edema model of inflammation in mice. Topically applied ethanolic extract reduced edema in a dose-dependent manner, resulting in a maximum inhibition of 73 ± 3% and an ID50 value of 0.05 (range: 0.02–0.13) mg/ear. Myeloperoxidase (MPO) activity was also inhibited by the extract, resulting in a maximum inhibition of 60 ± 6% (0.6 mg/ear). All of the fractions tested caused inhibition of edema formation and of MPO activity. Treatment with the ethyl acetate fraction was the most effective, resulting in inhibition levels of 75 ± 5 and 54 ± 8% for edema formation and MPO activity, respectively. However, treatment of mice with isolated compounds [apigenin-6-C-β-l-fucopyranoside and apigenin-6-C-(2″-O-α-l-rhamnopyranosyl)-β-l-fucopyranoside] did not yield successful results. Apigenin-6-C-(2″-O-α-l-rhamnopyranosyl)-β-l-fucopyranoside caused only a mild reduction in edema formation (28 ± 11%). Taken together, these preliminary results support the popular use of A. carambola as an anti-inflammatory agent and open up new possibilities for its use in skin disorders.

Simvastatin ointment, a new treatment for skin inflammatory conditions

BACKGROUND Statins represent a class of drugs that effectively lowers cholesterol, however they also possess pleiotropic effects, like promotion of angiogenesis, prevention of bone loss, immunomodulatory and anti-inflammatory effects. OBJECTIVES Thus, the aim of this study was to investigate the activity of simvastatin topically applied in mice in acute and chronic skin inflammation models. METHODS Skin inflammation was induced in mice ears by topical application of 12-O-tetradecanoylphorbol acetate (TPA). In the acute model, ear oedema was measured by the increase of ear thickness 6h after TPA (2.5μg/ear). The chronic inflammatory process was induced by multiple applications of TPA (2.0μg/ear) for nine alternate days, and the oedema was measured daily as the increase in ear thickness. RESULTS Topical treatment was applied immediately after TPA in acute model or started at 5th day of chronic experiment. For acute model treatment was simvastatin (0.24, 0.71 and 2.40μM), dexamethasone (0.13μM), both in acetone or vehicle alone (acetone). In chronic model simvastatin (1% and 3%) and dexamethasone (0.5%) were incorporated in ointment preparations, and a group received ointment alone (vehicle). Samples of ear tissue (6mm) were taken from acute and chronic models, weighted and prepared for histological analysis and myeloperoxidase (MPO) enzymatic activity evaluation. Application of simvastatin in acetone reduced the ear oedema after a single TPA application in a dose dependent manner [ID(50) of 0.47 (0.22-1.13) μM], and the MPO enzymatic activity up to 61±10%. Also, both simvastatin ointment preparations 1% and 3% reduced acute TPA-induced ear oedema in 55±7% and 65±8%, respectively. In the chronic model, simvastatin ointment 1% was able to reduce ear oedema (25±3%) and ear weight (10±1%), though 3% formulation augmented both parameters. Histological analysis revealed a reduction of swelling and leukocyte migration in the acute model for both the formulations of simvastatin (1% and 3%), while in chronic model simvastatin 1% decreased ear swelling and epidermal thickness, but simvastatin 3% increased both parameters. CONCLUSION The results confirm the anti-inflammatory activity of simvastatin when applied topically in both acute and chronic models of skin inflammation. Besides, the formulation of simvastatin ointment 1% shows to be a very effective formulation for a chronic usage.

Combretum leprosum Mart. (Combretaceae): Potential as an antiproliferative and anti-inflammatory agent

ETHNOPHARMACOLOGICAL RELEVANCE Combretum leprosum is a species that is popularly used in Brazil as a healing agent to treat skin problems and lesions. In this study we investigated the possible potential of this extract to treat inflammatory and hyperproliferative skin conditions. MATERIALS AND METHODS Classical models of skin inflammation such as TPA- and croton oil-induced mouse ear oedema were applied in order to verify the potential topical anti-inflammatory activity of the ethanolic extract from flowers of Combretum leprosum. RESULTS Topical application of ethanolic extract promoted a dose-dependent inhibition of phorbol ester-induced ear oedema, reduced myeloperoxidase activity and IL-6 tissue levels with inhibition comparable to dexamethasone (positive control). Histological and immunohistochemical analysis revealed that ethanolic extract also suppressed cell infiltration. Ethanolic extract altered inflammatory parameters on a chronic skin inflammation model induced by repeated applications of croton oil, decreasing ear oedema, epidermal hyperproliferation and cell infiltration. In addition, immunohistochemical analysis showed that the extract decreased PCNA expression on the epidermis. CONCLUSION Taken together, these results suggest that the extract from flowers of Combretum leprosum could be considered as a new potential tool for the treatment of several skin inflammatory diseases since it reversed the skin inflammatory and hyperproliferative process in a very significant manner. Further investigations are needed in order to verify the cellular mechanism and safety of Combretum leprosum extract.

Rhamnogalacturonan from Acmella oleracea (L.) R.K. Jansen: Gastroprotective and Ulcer Healing Properties in Rats

A rhamnogalacturonan (RGal) isolated from Acmella oleracea (L.) R.K. Jansen administered by oral route showed gastroprotective activity against acute lesions induced by ethanol. In this study, we investigated the gastric ulcer healing effect of RGal and its mechanisms of action. Intraperitoneal treatment of animals with RGal protected the gastric mucosa against acute lesions induced by ethanol, with participation of gastric mucus. Furthermore, in the chronic ulcer model, oral administration of RGal accelerates the gastric ulcer healing, accompanied by increasing of cellular proliferation and gastric mucus content, reducing inflammatory parameters and oxidative stress. In addition, the repeated 7 days-treatment of animals with RGal did not show alterations of clinical and behavioral symptoms, body and organs weights or plasmatic biochemical parameters. Collectively, these results showed that RGal has an interesting antiulcerogenic activity and could constitute an attractive molecule of interest for the development of new antiulcer agents.

B1 and B2 kinin receptor participation in hyperproliferative and inflammatory skin processes in mice

BACKGROUND Kinins are released during dermal injury and inflammation and seem to contribute to the pathogenesis of cutaneous diseases. OBJECTIVE Participation of kinins in skin inflammatory process was evaluated using knockout mice and non-peptide kinin receptor antagonists. METHODS Chronic skin inflammation was induced by multiple applications of TPA in mice ear. RESULTS The B(2) knockout mice (B(2)(-/-)) showed a significant increase of ear weight (23 ± 10%) and epidermal cellular hyperproliferation and acanthosis formation upon histological analysis when compared with wildtype mice. Also, evaluation of PCNA levels by Western blot and immunohistochemistry confirmed the increase in the epidermis hyperproliferation in the ear skin of B(2)(-/-) mice. In contrast, no modification in these parameters was detected in B(1) knockout mice (B(1)(-/-)). However, mice lacking both kinin receptors (B(1)B(2)(-/-)) presented a considerable reduction of epidermis thickness and in PCNA levels. Following the establishment of skin inflammation (5th day of TPA application) treatment with the non-peptide antagonists SSR 240612 (B(1) receptor antagonist), FR 173657 (B(2) receptor antagonist), or SSR 240612 plus FR 173657 topically applied, caused a significant inhibition of ear weight (20 ± 5%, 34 ± 4% and 32 ± 6%, respectively). In the histological analysis, the antagonists produced a reduction in epidermal hyperplasia and acanthosis formation; but the treatment with a combination of the two antagonists did not increase efficacy. CONCLUSION Kinin receptors seem to be involved in the control of the keratinocyte hyperproliferative process, and non-peptide kinin receptor antagonists may be useful tools in the treatment of hyperproliferative skin disorders.

In vivo participation of nitric oxide in hyperproliferative epidermal phenomena in mice.

A significant involvement of nitric oxide (NO) in the process of keratinocyte proliferation is reported with many divergences. To determine the involvement of NO in the hyperproliferative process of epidermis in vivo, non-selective inhibitor (N(G)-nitro-L-arginine-methyl ester.HCl: L-NAME) and selective inhibitors for inducible NO synthase (iNOS) and neuronal NO synthase (nNOS) (Aminoguanidine: AG and 7-Nitroindazole: 7-NI, respectively) and a NO-donor (Sodium nitroprusside: SNP) were topically applied twice a day in mice ear treated with multiple applications of croton oil. L-NAME and 7-NI treatments decreased and SNP increased ear edema formation. However, ear weight was reduced in groups that received L-NAME and 7-NI, while the AG and SNP groups presented an increment. The histological evaluation of epidermis thickness showed that all NOS inhibitors were able to prevent the increase in epidermis width caused by croton oil, while SNP contributed to enlargement. The same results were observed in the PCNA staining, where treatments with NOS inhibitors caused a reduction in the number of cells in the epidermis, while SNP caused an enhancement. 7-NI treatment reduced polymorphonuclear and mononuclear leukocytes migration when compared to the control group. The AG application increased the migration of polymorphonuclear and mononuclear cells, while the SNP enhanced only the polymorphonuclear cells. Therefore, in the skin NO produced by nNOS is involved in the control of keratinocyte hyperproliferation, with the contribution of iNOS. In the animal model of cutaneous chronic inflammation by croton oil, NO is involved in the exudation and leukocyte migration, with participation of all three enzymes.

Hydroalcoholic extract of Sapium glandulatum (Vell.) Pax displays potent anti-inflammatory activities through a glucocorticoid receptor-dependent pathway

BACKGROUND Ethnobotanical studies of the Sapium genus reveal that many species are widely used in several countries as therapeutic drugs and they are widely used in folk medicine for treatment of different diseases, including skin inflammation. This raises interest in the study of the pharmacological properties and phytochemical composition of these plants. The biological properties of Sapium glandulatum, a native species of southern Brazil, has not been reported in the literature. PURPOSE The aim of the present study was to investigate the anti-inflammatory action of the hydroalcoholic extract of Sapium glandulatum (EHSG) leaves in mouse models of acute or chronic skin inflammation. STUDY DESIGN/METHODS Topical effects of EHSG were evaluated in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced edema in the ear. Systemic effects of the extract were studied in a TPA-induced ear edema model, as well as in a carrageenan-induced paw edema model. To gain insight into the mechanism by which EHSG blocked inflammation, we evaluated the role of glucocorticoid receptors (GR) using the TPA-induced ear edema model and also measured specific binding in a glucocorticoid assay. Possible adverse effects of EHSG were evaluated after multiple treatments with the extract in the skin atrophy model on the ear and with the alkaline comet assay. RESULTS EHSG presented potent anti-inflammatory activity when applied topically in acute and chronic models, inhibiting edema formation and leukocyte migration as well as expression pro-inflammatory cytokines IL-1β, IL-6 and TNF-α in the tissue. Similar anti-inflammatory effects were found following oral treatment in both ear and paw edema models. Strikingly, the EHSG-induced blockade of leukocyte migration was reversed by mifepristone, a GR antagonist. Additionally, a specific binding assay revealed that ESGH interacts with GR. Multiple treatments with EHSG failed to induce adverse effects when evaluated in the skin atrophy model and bone marrow genotoxicity test. CONCLUSION Taken together, our data suggest that EHSG is a potential source of anti-inflammatory tool compounds for the treatment of pro-inflammatory-derived skin diseases, and its mechanism of action may be, at least in part, via the GR pathway.

Anti-proliferative and anti-inflammatory effects of 3β,6β,16β-Trihydroxylup-20(29)-ene on cutaneous inflammation

ETHNOPHARMACOLOGICAL RELEVANCE 3β,6β,16β-Trihydroxylup-20(29)-ene (TTHL) is a triterpene isolated from the flowers of Combretum leprosum, a plant used in folk medicine in the north of Brazil for the treatment of skin disorders. AIM OF THE STUDY In the present study, TTHL was evaluated as a potential topical anti-inflammatory and anti-proliferative agent through in vivo and in vitro models. MATERIAL AND METHODS Anti-inflammmatory and anti-proliferative effects of TTHL were assessed using Swiss mice in acute and chronic models of skin inflammation induced by 12-O-tetradecanoylphorbol-acetate (TPA) application. Anti-proliferative activity was proved through in vitro experiments with the HaCaT human keratinocyte cell line. RESULTS Treatment with TTHL inhibited inflammatory parameters such as oedema formation and cellular infiltration in acute and chronic models. In the chronic model, TTHL also inhibited epidermal hyperproliferation, as evidenced by reduction of epidermis thickness and proliferating cell nuclear antigen expression. The anti-proliferative effect was confirmed by the capability of TTHL in reducing the proliferation and inducing cell apoptosis of HaCaT cells. Suggesting a mechanism of action, TTHL showed activation of corticosteroid receptors, but without the induction of corticosteroid-related cutaneous side effects. CONCLUSION Our results demonstrate consistent anti-inflammatory and anti-proliferative activity and assign TTHL as a valuable tool in the development of a new treatment for skin inflammatory and proliferative diseases, such as psoriasis.