Abstract
Nutrition affects the amounts of important skin molecules, such as type Ⅰ and Ⅲ collagen, hyaluronan and ceramide, and decreases in these can lead to loss of moisture and inhibition of immune functions in the skin.
Protein malnutrition affects the status of dermal type Ⅰ and type Ⅲ tropocollagens, the major structural proteins in the skin, with a concomitant decrease in their mRNA levels, type Ⅲ collagen being most severely affected. Furthermore, there may be an influence on the skin hyaluronan content and mRNA levels of hyaluronan synthases (has) 2 and 3. In contrast, the synthesis of ceramide is not affected.
A high-fat diet also reduced the mRNA levels of COL1A1 and has2, with a consequent decrease of type Ⅰ tropocollagen and hyaluronan in the skin. In this case the level of ceramide in the epidermis is impacted, the mRNA levels for serine palmitoyltransferase, the key enzyme of ceramide synthesis, being reduced. These decreases might be all be attributable to suppressing the action of TGF-beta1, IGF-I and adiponectin. In conclusion, protein malnutrition and a high fat diet are deleterious for skin function.
