Un rappel des différentes cibles des hormones sur la peau

A review about the hormonal targets of the skin (B.Soutou).

• pregnancy is divided into 3 phases.

1. fertilization to implantation (1st week)
2. organogenesis
3. Maturation of organs

• after the corpus luteum is activated it is implicated in the following: synthesis of progesterone, others: estradiol, 17 hydroxyprogesterone, relaxin
• placenta synthesizes Sp1m PAPP-A,  peptides and steroids

the skin is not only a target but is a peripheral endocrine organ

• skin changes are due to:

1. increase in circulating hormones
2. vascular expansion
3. mechanical compression by the uterus

• Estrogens:

1. estrogens act through intranuclear receptors: but on the skin sites and mechanisms are still poorly understood.
2. estrogen receptor alpha is not marked but estrogen receptor beta is activated in the skin
3. estrogen enhances skin proliferation and collagen synthesis by teh fibroblasts
4. estrogen receptor is present on hair follicle and prolongs anagen phase and thus the size and length of the hair follicle
5. estrogen also suppresses sebaceous gland size. However the mechanisms on the eccrine gland is not understood.
6. estrogen could stimulate EGF and acts by increasing intracellular calcium

• progesterone

1. receptors are found in the epidermis and stimulates the production of keratinocytes
2. acts on eccrine glands
3. suppresses MMP-1 expression in fibroblastes: increases collagen by decreasing its breakage
4. stimulated melanocytes: melanogenesis
5. does it stimulate sebocytes ?

Estrogens and Progesterone increases the adaptive immune response in the skin

• Prolactin

1. expressesd mainly in hair follicle
2. acts membrane receptors
3. induces hair follicle catagen phase

• Placental growth factor

1. member of VEGF
2. angiogenic effect on the skin

• Hpl has an action on angiogenesis

• Androgens

1. act on a nuclear receptor
2. act on keratinocytes, sebocytes, sweat gland, endothelial cells and melanocytes

• melanoctyes have the following receptors:

1. ER alpha and B receptors
2. NGF receptor
3. SCF receptor
4. VEGF receptor
5. CRH receptor
6. less understood for  other hormones

Source of Information: WS02. Physiological Changes In Pregnancy: A Frequent Event. 2011 (10) – 20th Annual Congress of the EADV (European Academy of Dermatology and Venerology) – Lisbon (Lisboa), Portugal