Techniques for the Discovery and Evaluation of Drugs Against Alopecia

February 2011 in “ Expert Opinion on Drug Discovery ”

Ajay Semalty, Mona Semalty, Gopal Krishna Joshi, Mahiraj Singh Rawat

alopecia hair loss hair growth cycle in vivo models in vitro models mouse models macaque models hair length measurement histological analysis plant extracts genetically modified animal models hair growth

Studysummary This review discusses techniques and models for assessing hair growth activity but reports no new clinical findings, emphasizing the need for standardization and improved animal models.

Our plain-language summary. Not medical advice or a treatment recommendation. Consult a qualified healthcare professional before changing treatment. Full disclaimer

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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