Techniques for the discovery and evaluation of drugs against alopecia
February 2011
in “Expert Opinion on Drug Discovery”
TLDR We need better treatments for hair loss, and while test-tube methods are helpful, they can't fully replace animal tests for evaluating new hair growth treatments.
The 2011 document reviews the challenges and techniques in drug discovery and evaluation for alopecia, emphasizing the need for more effective treatments due to the psychological impact of hair loss. It discusses the anatomy of hair, the hair growth cycle, and the criteria for an effective alopecia drug. Various in vivo and in vitro models are described for assessing hair growth, including mouse and macaque models, with the macaque monkey being the second most relevant model after humans. The document details methods for evaluating hair growth in studies, such as hair length measurement and histological analysis, and cites specific studies on the effects of treatments like plant extracts. It also discusses the limitations of current techniques and the potential of in vitro systems and genetically modified animal models to replace whole-animal systems in research. The document concludes that while in vitro systems are useful, they cannot yet fully replace animal assays for initial assessments of hair growth treatments.
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