Pablo Andrés González

Relationship Between Vitiligo and the Stress Produced Hormone Corticotropin

Dr. Edwin Vázquez Ph.DJuly 12,2011University of Puerto Rico CayeyBiol-3009

About the diseaseVitiligo is a pigmentation disorder in which

melanocytes in the skin are destroyed (a result of apoptosis).

As a result white patches appear on the skin.

The hair that grows on areas affected by vitiligo sometimes turns white.

It affects 1% of the worldwide population regardless of sex, age, and race.

ClassificationVitiligo focalis- only one or more maculae in

one areaVitiligo segmentalis- one or more maculae

in a quasidermatomal patternVitiligo acrofacialis- distal extremity and

faceVitiligo vulgaris- scattered macules over the

entire bodyVitiligo universalis- Almost all body

depigmentation

MelanocytesMelanocytes are special skin cells located

in the bottom layer of the epidermis that are responsible for the production of melanin.

ACTHACTH is a hormone that stimulates the

adreal cortex and its produced as a response to corticotropin- releasing hormones.

Corticotropin is released with stress.

PathogenesisThere are four hypothesis to why these

melanocytes are affected:Autoimmune hypothesisNeural hypothesisSelf-destruction hypothesisCombination of 1, 2, and 3

Certain modifications in the immune system result in the destruction of the melanocytes.

The presence of a certain neurochemical mediator that is cytotoxic to pigment cells.

Precursors of melanogenesis are toxyc to melanocytes.

All of these factors are involved in the destruction of the melanocytes.

Other types of disordersPsoriasis bulgarisAlopecia areataSeborrhea

HypothesisIf I submit subjects, such as mice, to a

stressful environment they will produce Adrenocorticotropic (ACTH or corticotropin) hormone and destroy they melanocytes. By analyzing this substance I can create something to counter that effect or to regenerate the damaged melanocytes.

ObjectiveTo determine why the body produces

adrenocorticotropic hormone during periods of extreme emotional stress that affect the melanocytes in the skin.

MethodologySurvey different types of people that have

or are prone to the disease.Make a culture of normal (people with

medical history of vitiligo) and affected melanocytes. Then expose them to ACTH.

StepsMake different groups of 5 people,

depending on their age. - One group 1-12 years - Another group 15-20 years - A group of 23-55 years - One last group of 60-73 years

Ask them If they have any medical history of Vitiligo.

Question them about the first time they notice an outbreak of the disorder.

Where did the white patches start.Did they feel any different.What did they do to manage their

condition.

Expected ResultsThe production of ACTH causes the

destruction of melanocytes if the person has a medical history of Vitiligo. The melanocytes of the people affected with vitiligo will start to undergo apoptosis.

ReferencesYaghoobi R..Vitiligo: a review of the

published work. PubMed.gov. May 38 201. http://www.ncbi.nlm.nih.gov/pubmed/21667529

Wu Cs. Narrow-band UVB irradiation stimulates the migration and functional development of vitiligo-IgG antibodies-treated pigment cells. PubMed.gov. May 4, 2011. http://www.ncbi.nlm.nih.gov/pubmed/21545543

Kadri Asif M. Causes of Vitiligo. 2008. http://www.vitiligoguide.com/vitiligo-videos/causes-of-vitiligo-video/

Inoue K. Stress augmented ultraviolet-irradiation-induced pigmentation. PubMed.gov. Kuly 12, 2003. http://www.ncbi.nlm.nih.gov/pubmed/12839577

Costin Gertrude. Human skin pigmentation: melanocytes modulate skin color in response to stress. The FASEB Journal. January 22, 2007. http://www.fasebj.org/content/21/4/976.short

Lerner Aron, A Mouse Model for Vitiligo http://hamiltongen677s10.weebly.com/uploads/3/6/1/9/3619132/a_mouse_model_for_vitiligo.pdf

Njoo et.al. Vitiligo: A review. University of Amsterdam. 1997-1998