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1.
Arch Toxicol ; 91(2): 521-547, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26997338

RESUMO

A thorough understanding of which of the effects assessed in the in vivo Draize eye test are responsible for driving UN GHS/EU CLP classification is critical for an adequate selection of chemicals to be used in the development and/or evaluation of alternative methods/strategies and for properly assessing their predictive capacity and limitations. For this reason, Cosmetics Europe has compiled a database of Draize data (Draize eye test Reference Database, DRD) from external lists that were created to support past validation activities. This database contains 681 independent in vivo studies on 634 individual chemicals representing a wide range of chemical classes. A description of all the ocular effects observed in vivo, i.e. degree of severity and persistence of corneal opacity (CO), iritis, and/or conjunctiva effects, was added for each individual study in the database, and the studies were categorised according to their UN GHS/EU CLP classification and the main effect driving the classification. An evaluation of the various in vivo drivers of classification compiled in the database was performed to establish which of these are most important from a regulatory point of view. These analyses established that the most important drivers for Cat 1 Classification are (1) CO mean ≥ 3 (days 1-3) (severity) and (2) CO persistence on day 21 in the absence of severity, and those for Cat 2 classification are (3) CO mean ≥ 1 and (4) conjunctival redness mean ≥ 2. Moreover, it is shown that all classifiable effects (including persistence and CO = 4) should be present in ≥60 % of the animals to drive a classification. As a consequence, our analyses suggest the need for a critical revision of the UN GHS/EU CLP decision criteria for the Cat 1 classification of chemicals. Finally, a number of key criteria are identified that should be taken into consideration when selecting reference chemicals for the development, evaluation and/or validation of alternative methods and/or strategies for serious eye damage/eye irritation testing. Most important, the DRD is an invaluable tool for any future activity involving the selection of reference chemicals.


Assuntos
Cosméticos/efeitos adversos , Cosméticos/classificação , Avaliação Pré-Clínica de Medicamentos/métodos , Olho/efeitos dos fármacos , Testes de Toxicidade/métodos , Animais , Cosméticos/toxicidade , Bases de Dados Factuais , Europa (Continente) , Humanos , Irritantes/classificação , Irritantes/toxicidade , Coelhos , Reprodutibilidade dos Testes
2.
Toxicol In Vitro ; 29(5): 976-86, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25868915

RESUMO

Allergic contact dermatitis is a delayed T-cell mediated allergic response associated with relevant social and economic impacts. Animal experiments (e.g. the local lymph node assay) are still supplying most of the data used to assess the sensitization potential of new chemicals. However, the 7th amendment to the EU Cosmetic Directive have introduced a testing ban for cosmetic ingredients after March 2013. We have developed and optimized a stable and reproducible in vitro protocol based on human peripheral blood monocyte derived dendritic cells to assess the sensitization potential of chemicals. To evaluate the transferability and the predictivity of this PBMDCs based test protocol, a ring study was organized with five laboratories using seven chemicals with a known sensitization potential (one none-sensitizer and six sensitizers, including one pro-hapten). The results indicated that this optimized test protocol could be successfully transferred to all participating laboratories and allowed a correct assessment of the sensitization potential of the tested set of chemicals. This should allow a wider acceptance of PBMDCs as a reliable test system for the detection of human skin sensitizers and the inclusion of this protocol in the toolbox of in vitro methods for the evaluation of the skin sensitization potential of chemicals.


Assuntos
Alérgenos/toxicidade , Células Dendríticas/imunologia , Alternativas aos Testes com Animais , Dermatite Alérgica de Contato/imunologia , Humanos , Laboratórios , Monócitos/citologia , Reprodutibilidade dos Testes
3.
Toxicol In Vitro ; 29(1): 259-70, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25448812

RESUMO

The need for non-animal data to assess skin sensitisation properties of substances, especially cosmetics ingredients, has spawned the development of many in vitro methods. As it is widely believed that no single method can provide a solution, the Cosmetics Europe Skin Tolerance Task Force has defined a three-phase framework for the development of a non-animal testing strategy for skin sensitization potency prediction. The results of the first phase ­ systematic evaluation of 16 test methods ­ are presented here. This evaluation involved generation of data on a common set of ten substances in all methods and systematic collation of information including the level of standardisation, existing test data,potential for throughput, transferability and accessibility in cooperation with the test method developers.A workshop was held with the test method developers to review the outcome of this evaluation and to discuss the results. The evaluation informed the prioritisation of test methods for the next phase of the non-animal testing strategy development framework. Ultimately, the testing strategy ­ combined with bioavailability and skin metabolism data and exposure consideration ­ is envisaged to allow establishment of a data integration approach for skin sensitisation safety assessment of cosmetic ingredients.


Assuntos
Alternativas aos Testes com Animais/métodos , Dermatite Alérgica de Contato/etiologia , Linhagem Celular , Cosméticos , Epiderme/efeitos dos fármacos , Humanos , Técnicas In Vitro , Interleucina-18/análise , Queratinócitos/efeitos dos fármacos , Medição de Risco , Pele/efeitos dos fármacos , Células U937/efeitos dos fármacos
4.
Dermatitis ; 25(1): 11-21, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24407057

RESUMO

Although adoption of skin sensitization in vivo assays for hazard identification is likely to be successful in the next few years, this does not replace their use in potency prediction. Notably, measurement of potency of skin sensitizers in the local lymph node assay has been important. However, this local lymph node assay potency measure has not been formally assessed against a range of substances of known human sensitizing potential, because the latter is lacking. Accordingly, criteria for human data have been established that characterize 6 categories of human sensitizing potency, with 1 the most potent and 5 the least potent; category 6 represents true nonsensitizers. The literature has been searched, and 131 chemicals assigned into these categories according to their intrinsic potency judged only by the available human information. The criteria and data set generated provide a basis for examination of the capacity of nonanimal approaches for the determination of human sensitization potency.


Assuntos
Alérgenos/classificação , Alérgenos/toxicidade , Dermatite Alérgica de Contato/etiologia , Relação Dose-Resposta Imunológica , Humanos , Ensaio Local de Linfonodo , Nível de Efeito Adverso não Observado , Testes do Emplastro
5.
BJU Int ; 110(6 Pt B): E301-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22520557

RESUMO

UNLABELLED: What's known on the subject? and What does the study add? Pervasive inflammatory infiltrates, mainly composed of chronically activated T cells and monocytes/macrophages, have been observed in benign prostatic hyperplasia (BPH). Permixon®, a hexanic lipidosterolic extract of Serenoa repens (hexanic LSESr) used to treat urinary dysfunction in BPH patients, has anti-inflammatory activities. This paper provides new insights into the anti-inflammatory properties of Permixon®. We report that hexanic LSESr inhibits early steps of leukocyte infiltration in vitro by downregulating MCP-1/CCL2 and VCAM-1 expression. OBJECTIVE: To investigate the mechanisms by which hexanic lipidosterolic extract of Serenoa repens (hexanic LSESr) may prevent leukocyte infiltration in benign prostatic hyperplasia by studying its impact on monocyte chemoattractant protein 1/chemokine (C-C motif) ligand 2 (MCP-1/CCL2) and vascular cell adhesion molecule 1 (VCAM-1) expression in vitro. MATERIALS AND METHODS: After pretreatment with hexanic LSESr, human prostate (epithelial and myofibroblastic) cells and vascular endothelial cells were stimulated with proinflammatory cytokines. MCP-1/CCL2 and VCAM-1 mRNA expression was quantified by real-time PCR. ELISA kits were used to determine MCP-1/CCL2 levels in culture supernatants and VCAM-1 expression in living cells. RESULTS: Hexanic LSESr reduced MCP-1/CCL2 mRNA levels in both epithelial (BPH-1) and myofibroblastic (WPMY-1) prostate cell lines. Hexanic LSESr downregulated MCP1/CCL2 secretion by WPMY-1 cells in a concentration-dependent manner, more efficiently than Serenoa repens extracts obtained by supercritical carbon dioxide extraction. Hexanic LSESr inhibited tumour-necrosis-factor-α-induced MCP-1/CCL2 secretion by the human vascular endothelial cell line EAhy.926, as well as surface VCAM-1 protein expression, in a concentration-dependent manner. CONCLUSIONS: Hexanic LSESr impedes key steps of monocyte and T cell attraction and adherence by inhibiting MCP-1/CCL2 and VCAM-1 expression by human prostate and vascular cells in an inflammatory environment. These findings provide new insights into the anti-inflammatory effects of the hexanic lipidosterolic extract of Serenoa repens, Permixon®, in benign prostatic hyperplasia.


Assuntos
Quimiocina CCL2/antagonistas & inibidores , Quimiocina CCL2/biossíntese , Hexanos/farmacologia , Extratos Vegetais/farmacologia , Serenoa , Molécula 1 de Adesão de Célula Vascular/biossíntese , Molécula 1 de Adesão de Célula Vascular/efeitos dos fármacos , Células Cultivadas , Humanos
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