Following reports of patients suffering hair loss during treatment for Parkinson’s Disease, scientists have discovered that a neurotransmitter* associated with the disease may have a new use in the fight against unwanted excess hair, new research published the British Journal of Dermatology reveals.

Researchers at The University of Manchester as well as research centres in Germany and Hungary looked at the role of a chemical called dopamine in relation to hair growth and discovered that, when tested in the laboratory, dopamine increases the number of hair follicles that are in the catagen phase of the hair cycle, the period at which the hair stops growing and prepares to fall out.

Dopamine is a neurotransmitter produced in the brain that has many functions in the body, including in behavioural roles such as reward seeking behaviour. Decreased levels of dopamine are associated with several common disorders, including Parkinson’s Disease and Restless Leg Syndrome. A drug called L-DOPA or levodopa is commonly used in the treatment of Parkinson’s to replace depleted dopamine levels caused by the disease.

Anecdotally, treatment with levodopa or other chemicals that imitate the actions of dopamine have been associated with diffuse hair loss, predominantly in women. Given the widespread use of both dopamine agonists and antagonists (i.e. drugs that either mimic or inhibit dopamine actions) in clinical practice, the researchers examined whether dopamine can directly alter human hair follicle growth.

The scientists found that treating healthy human scalp hair follicles with 1000nM of dopamine, in a laboratory setting rather than on living subjects, more than doubled the percentage of hair follicles in catagen, i.e. of “hair factories” that have stopped producing a hair shaft. Around 19 per cent of hair follicles were in catagen in the control group compared to 53 per cent of hair follicles treated with dopamine 1000nM in the laboratory.

Ralf Paus, Professor of Cutaneous Medicine at The University of Manchester and one of the study’s authors said: “This study provides the first direct evidence that dopamine treatment negatively affects human hair growth, namely that it pushes hair follicles out of their phase of growth and active hair shaft production. This is entirely consistent with case reports of hair loss in women being treated with dopamine agonists.”

Nina Goad of the British Association of Dermatologists said: “This is a perfect example of research confirming the experiences of patients that have been reported but not previously backed up by any hard clinical data. Having this scientific evidence may lead to new treatments for hirsutism – when an individual grows too much body or facial hair, which can cause huge embarrassment and greatly alter their quality of life. In principle, it is conceivable that dopamine could be selectively administered externally to hirsute skin in a cream or lotion.”

Ends

*Neurotransmitters are the molecules that the nervous system uses for communication between cells.

Notes to editors:

1. If using this information, please ensure you mention that the study is being released in the British Journal of Dermatology, the official publication of the British Association of Dermatologists

2. For more information please contact: Nina Goad, British Association of Dermatologists, Phone: 0207 391 6094, Email: nina@bad.org.uk, Website: www.bad.org.uk

3. Articles in the BJD can be viewed online: www.brjdermatol.org
British Journal of Dermatology: Dopamine is a novel, direct inducer of catagen in human scalp hair follicles in vitro.
E.A. Langan,1,2 E. Lisztes,3 T. Bíró,3 W. Funk,4 J.E. Kloepper,2 C.E.M. Griffiths1 and R. Paus1,2
1Dermatology Research Centre, The University of Manchester, Manchester Academic Health Science Centre, Manchester, U.K.
2Experimental Dermatology, Universitätsklinikum Schleswig Holstein, Lübeck, Germany
3DE-MTA ‘Lendulet’ Cellular Physiology Research Group, Department of Physiology, University of Debrecen, H-4032 Debrecen, Hungary
4Clinic Dr Kozlowski, Munich, Germany
DOI REFERENCE: DOI 10.1111/bjd.12113
Accepted for publication, 7th October 2012

The British Association of Dermatologists is the central association of practising UK dermatologists. Our aim is to continually improve the treatment and understanding of skin disease.

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