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-1ß, 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.

Effect of a Garcinia gardneriana (Planchon and Triana) Zappi hydroalcoholic extract on melanogenesis in B16F10 melanoma cells.

ETHNOPHARMACOLOGY RELEVANCE: Garcinia gardneriana (Planchon and Triana) Zappi (Clusiaceae) is popularly called "bacopari" in southern Brazil. The leaves of this plant are traditionally used to treat skin disorders. AIM OF STUDY: This study evaluated the effects of a hydroalcoholic extract of Garcinia gardneriana leaves (HEGG) on B16F10 murine melanoma cells in order to search for new depigmenting agents. MATERIALS AND METHODS: The effects of HEGG were assessed in melanin content assays in B16F10 melanoma cells compared with the reference drug kojic acid (500mM). Melanin content was measured after spontaneous melanogenesis, UVB-induced melanogenesis and melanogenesis induced by α-MSH. At the same time, cell viability assays were conducted. Intracellular and mushroom tyrosinase activity assays were employed to evaluate the effect of HEGG on tyrosinase activity. RESULTS: HEGG decreased the level of melanin under all three experimental conditions of melanin content evaluation without reducing cell viability. In intracellular tyrosinase assays, the enzyme's activity was reduced about 19% with extract concentrations ranging 0.1-10µg/mL. In the mushroom tyrosinase activity assay a maximal inhibition of 35% (1000µg/mL) was observed. CONCLUSION: These results suggest that HEGG inhibition relates to its tyrosinase activity. Therefore, the hydroalcoholic extract of Garcinia gardneriana shows great potential for use as a depigmenting agent in hyperpigmentation 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.

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.