Evaluation of Ointments with Daldinia eschscholtzii in Wound Healing in an In Vivo Model.

Fungi are a source of a variety of secondary metabolites of importance in different areas of biotechnology. Several compounds have been characterized with antioxidant, antimicrobial, and anti-inflammatory activity from fungi of the division of the Ascomycota, among which is the species Daldinia eschscholtzii, an endophyte fungus of pantropical distribution. In this study, we evaluated the effect of an ointment made with D. eschscholtzii on the wound healing of BALB/c mice. The species was corroborated using a molecular marker Internal Transcribed Spacer (ITS1 and ITS4). The extracts and dust of the fungus were considered nontoxic as they caused a mortality of <15% in the nematode Panagrellus redivivus, and experimental ointments had no adverse effects on the skin of BALB/c mice. Wounds treated with the D. eschscholtzii ointments had 99.9-100% wound contraction after 17 days, which was similar to commercial healing (positive control). As such, the ointment of D. eschscholtzii is a natural alternative to improve wound healing.

Study of the dermal anti-inflammatory, antioxidant, and analgesic activity of pinostrobin.

Pinostrobin is a flavanone isolated from Renealmia alpinia (Rottb.) Maas, which is used to treat painful diseases and ailments; indigenous peoples use it as plasters. Different plant species have been reported as a source of this flavonoid, among which are: Boesenbergia rotunda, Cajanus cajan, Piper ecuadorense, Piper hispidum, Teloxys graveolens, Kaempferia pandurata, among others. Pinostrobin expresses potentially useful biological activities such as antioxidant, analgesic, and dermal anti-inflammatory, at low levels nonetheless due to its low solubility. The formation of inclusion complexes deems a good strategy to improve the pharmacologic effects of many substances. In the present work, we evaluated the dermal toxicity, analgesic and dermal anti-inflammatory activity of pinostrobin included in cyclodextrins, to improve those effects on experimental animals. To include pinostrobin, we used two of beta cyclodextrin (ßCD) and hydroxypropil beta cyclodextrin (HPßCD) complexes using two methods developed by Benesi-Hildebrand and Higuchi-Connors. Dermal anti-inflammatory activity was evaluated in experimental mice by inhibiting the edema generated by 12-O-tetradecanoylforbol-13-acetate (TPA). Analgesic activity was evaluated by inducing chemical pain by means of a Siegmund test. Antioxidant activities were measured with two in vitro tests. Analgesic and dermal anti-inflammatory activities of pinostrobin, as included in control and experimental complexes, showed comparatively better effects than pinostrobin without inclusion complexes. Our results indicate that both beta cyclodextrin (ßCD) and hydroxypropyl beta cyclodextrin (HPßCD) enhance the different effects of pinostrobin, which may indicate greater bioavailability.

Preclinical safety evaluation of amphotericin A21: A novel antifungal.

Safety studies are essential in drug development. This study evaluates the safety of Amphotericin A21 (AmB-A21), a derivative of amphotericin B with antifungal therapeutic potential. We performed a chronic toxicity study, a targeted organ study and a dermal irritation test. To evaluate chronic toxicity, 18 male adult rats were treated orally with AmB-21 (2 mg/kg) for 26 weeks. The effects on body-weight and animal health were measured, and haematological, clinical chemistry and histopathological tests were conducted on various organs. In the target organ toxicity study, male adult rats received a daily oral dose of AmB-21 (2 mg/kg) for 6 and 17 weeks; testicle histology and testosterone levels were then evaluated. For the dermal irritation study, AmB-21 (200 and 1000 mg/kg) was placed on the skin of adult male rabbits; macroscopic and microscopic studies, as well as haematological and clinical chemistry tests were then conducted. The chronic toxicity study revealed that AmB-21 caused testicle damage, and the testicle-targeted study showed structural alterations and changes in testosterone levels at 17 weeks. However, these alterations were no longer observed 8 weeks after discontinuation of treatment, and the testes showed very similar characteristics to those in the control group. The dermal irritation study showed skin thickening and reddening in rabbits treated with 2000 mg of AmB-A21 after 14 days of exposure. This same group also showed changes in liver enzymes, renal parameters and platelet levels. Based on our results, we consider AmB-21 to be a potential candidate for safe, long-term antifungal treatment given its reduced side effects.

Non-relevance of acute dermal toxicity testing for assessing human health protection in the regulatory decision-making for agrochemical formulated products.

Compared to oral toxicity tests, dermal toxicity tests offer little or no additional scientific information or public health protection for agrochemical-formulated products (US EPA, 2016). Based on that, a retrospective analysis of the results of acute oral and dermal LD50 studies of agrochemical products registered in Brazil was carried out by the Technical Group on Toxicological Risk Assessment (GT-ART) of the Brazilian Crop Protection Association (ANDEF). The data were obtained from 6 agrochemical industries that are associated to ANDEF, following these considerations: only rat studies were selected; only paired studies were chosen; only studies performed with top doses ≥2,000 mg/kg were selected; biological products were excluded. The dataset includes 342 formulated products in 21 formulation types. Among these 342 formulated products, 228 have a single active ingredient, 107 have 2 and 7 have 3 or more. The comparison of acute oral to dermal toxicity studies of agrochemical-formulated products registered in Brazil corroborates the United States Environmental Protection Agency (US EPA) conclusion on waiving acute dermal toxicity tests, which will result in avoiding unnecessary use of time and resources, data generation costs and animal testing.

Comparative analysis of Lacistema pubescens and dexamethasone on topical treatment of skin inflammation in a chronic disease model and side effects.

OBJECTIVES: This study aimed to evaluate the chronic topical anti-inflammatory activity of the pharmaceutical formulation ProHLP containing the hexane fraction of Lacistema pubescens (HLP). It was also investigated the possible cutaneous and systemic adverse effects of HLP and ProHLP in mice when compared to dexamethasone. METHODS: The chronic topical anti-inflammatory activity was determined by croton oil multiple application-induced mouse ear oedema model. Histopathological analyses of ear tissue samples sensitized with croton oil were performed. Cutaneous atrophy induced by HLP and topical glucocorticoid treatments and excision skin wounds model to evidenced possible adverse reactions were also determined. KEY FINDINGS: ProHLP significantly reduced the mice ear oedema and considerably accelerated the wound-healing process. Also, HLP did not lead cutaneous atrophy and preserved the clinical aspect of the thymus, adrenal and spleen, unlike dexamethasone. CONCLUSIONS: The results suggested that ProHLP is an efficient and safer pharmaceutical formulation to treat chronic inflammatory diseases.

Toxicidad aguda tópica e irritabilidad dérmica de la decocción de hojas de Piper auritum Kunth (caisimón de anís) / Acute topical toxicity and dermal irritability of decoction of Piper auritum Kunth (caisimón de anís)

INTRODUCCIÓN: el Piper auritum Kunth comúnmente conocido como caisimón de anís, o anisón en algunas regiones del país, es una planta ampliamente utilizada como antiinflamatorio tópico. Tanto la hoja calentada como la decocción aplicada sobre la zona dañada son empleadas por la población con este fin. OBJETIVO: determinar la toxicidad aguda tópica y la irritabilidad dérmica primaria de la decocción al 50 % de hojas frescas de Piper auritum. MÉTODOS: se emplearon hojas frescas colectadas el mismo día del ensayo y se utilizaron las técnicas descritas en las guías de la Organización para la Cooperación Económica y el Desarrollo (OECD), la 434 para la toxicidad dérmica utilizando ratas Wistar, manteniendo la decocción por 24 horas en contacto con la piel previamente afeitada; el peso de los animales fue controlado antes, durante y al concluir el experimento. Y la OECD 404 para la irritabilidad tópica empleando conejos Nueva Zelanda aplicando el extracto por 4 horas a la zona rasurada. RESULTADOS: no se apreciaron signos ni síntomas de toxicidad por la absorción dérmica en las ratas ni se observó evidencia de edema ni eritema en los conejos empleados. CONCLUSIONES: la decocción al 50 % de Piper auritum Kunth posee un índice de irritabilidad y una toxicidad dérmica bajas en nuestras condiciones de ensayo.

INTRODUCTION: Piper auritum Kunth, commonly known as caisimón de anís or anisón in some regions of the country, is a plant widely used as topical anti-inflammatory. To this end, leaves may be warmed up and applied to the damaged area or a decoction prepared and drunk. OBJECTIVE: determine the acute topical toxicity and primary dermal irritability of a 50 % decoction of Piper auritum fresh LEAVES. METHODS: fresh leaves collected on the same day of the assay were used to prepare a decoction, following the techniques described in Guideline 434 of the Organization for Economic Co-operation and Development (OECD 434) about dermal toxicity in Wistar rats. Decoction was kept in contact with previously shaved skin for 24 hours. The weight of animals was controlled before, during and upon completion of the experiment. OECD Guideline 404 was used for topical irritability in New Zealand rabbits, applying the extract to a previously shaved area for 4 hours. RESULTS: no sign or symptom of toxicity due to dermal absorption was observed in the rats. Rabbits did not show any evidence of edema or erythema. CONCLUSIONS: Piper auritum Kunth 50 % decoction has a low irritability and dermal toxicity rate in our test conditions.

Dermal toxicity, eye and dermal irritation and skin sensitization evaluation of a new formulation of Bacillus thuringiensis var israelensis SH-14.

Bacillus thuringiensis (Bt) is the best known and most widely used of all pesticidal microbes. The aim of this study was to assess the toxicity of a new formulation of Bacillus thuringiensis var israelensis SH-14 in rats through acute dermal toxicity, dermal and eye irritation experiments. The acute dermal toxicity and dermal and eye irritation studies were performed using rabbits according to the United States Environmental Protection Agency guidelines 885.3100, 870.2500 and 870.2500, respectively. The skin sensitization study was carried out in accordance to the EPA OPPTS 870.2600 using guinea pigs. There was no mortality and no evidence of treatment-related toxicity in acute dermal toxicity test. No dermal responses, including erythema/eschar or edema, were found in rabbits treated with the new formulation of Bti SH-14. Minimum response was observed after eye application of test substance. No skin sensitization reactions were observed after the challenge with the new formulation of Bti SH-14 in the Bti SH-14-treated guinea pigs. In summary, the present study demonstrated that the new formulation of Bti SH-14 is not acutely toxic via dermal route, has low eye irritation and would not cause dermal irritation or hypersensitivity to tested animals.