Innovative organotypic in vitro models for safety assessment: aligning with regulatory requirements and understanding models of the heart, skin, and liver as paradigms

The development of improved, innovative models for the detection of toxicity of drugs, chemicals, or chemicals in cosmetics is crucial to efficiently bring new products safely to market in a cost-effective and timely manner. In addition, improvement in models to detect toxicity may reduce the incidence of unexpected post-marketing toxicity and reduce or eliminate the need for animal testing. The safety of novel products of the pharmaceutical, chemical, or cosmetics industry must be assured; therefore, toxicological properties need to be assessed. Accepted methods for gathering the information required by law for approval of substances are often animal methods. To reduce, refine, and replace animal testing, innovative organotypic in vitro models have emerged. Such models appear at different levels of complexity ranging from simpler, self-organized three-dimensional (3D) cell cultures up to more advanced scaffold-based co-cultures consisting of multiple cell types. This review provides an overview of recent developments in the field of toxicity testing with in vitro models for three major organ types: heart, skin, and liver. This review also examines regulatory aspects of such models in Europe and the UK, and summarizes best practices to facilitate the acceptance and appropriate use of advanced in vitro models

Aspirations for older age in the 21st century: What is successful aging?

The literature on successful aging reveals a wide range of definitions, generally reflecting the academic discipline of the investigator. Biomedical models primarily emphasise physical and mental functioning as successful aging; socio-psychological models emphasise social functioning, life satisfaction and psychological resources as successful aging. Several studies also identify these factors as the precursors of successful aging. Moreover, research shows that older people consider themselves to have aged successfully, but classifications based on traditional medical models do not. Fewer studies have explored,lay views, and most of these have been exploratory or restricted to specific groups of areas. A model of successful aging needs to be multi-dimensional, incorporate a lay perspective for social significance, use a continuum rather than dichotomous cut-offs for "success" and lack of, and distinguish clearly between predictor and constituent variables