TLDR  Wnt5a slows down hair growth by blocking a specific pathway during hair regeneration.   
  The study found that Wnt5a suppresses the activation of the canonical Wnt/β-catenin signaling pathway during hair follicle regeneration, inhibiting hair growth. The study used experiments on mice to demonstrate this, and suggests that Wnt5a could be a potential target for hair loss treatments. The study also found that the canonical Wnt signaling pathway is necessary for hair follicle regeneration.
            45 citations
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  April 2016   in “Journal of Dermatological Science”
           45 citations
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  April 2016   in “Journal of Dermatological Science”    The Wnt/β-catenin pathway can activate melanocyte stem cells and may help regenerate hair follicles.  
      39 citations
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  January 2013   in “Journal of Investigative Dermatology”
           39 citations
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  January 2013   in “Journal of Investigative Dermatology”    Changing Wnt signaling can lead to more or less hair growth and might help treat hair loss and skin conditions.  
      19 citations
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  January 2013   in “International journal of medical sciences”
           19 citations
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  January 2013   in “International journal of medical sciences”    Increasing Wnt5a in mice skin delays hair growth but doesn't stop it.  
      77 citations
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  July 2012   in “Journal of Investigative Dermatology”
           77 citations
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  July 2012   in “Journal of Investigative Dermatology”    Wnt10b overexpression can regenerate hair follicles, possibly helping treat hair loss and alopecia.  
      20 citations
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  December 2010   in “JEADV. Journal of the European Academy of Dermatology and Venereology/Journal of the European Academy of Dermatology and Venereology”
           20 citations
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  December 2010   in “JEADV. Journal of the European Academy of Dermatology and Venereology/Journal of the European Academy of Dermatology and Venereology”    Decreased CD200 in hair follicles may cause immune issues in some alopecia areata cases.  
    
  
        
      16 citations
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  January 2016   in “International Journal of Medical Sciences”
           16 citations
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  January 2016   in “International Journal of Medical Sciences”    Wnt5a slows down hair growth by blocking a specific pathway during hair regeneration.