Biomol Ther.  2017 Sep;25(5):528-534. 10.4062/biomolther.2017.089.

Oral Administration of Glycine and Leucine Dipeptides Improves Skin Hydration and Elasticity in UVB-Irradiated Hairless Mice

• Park JI
• Lee JE
• Shin HJ
• Song S
• Lee WK
• Hwang JS

• KMID: 2389385
• DOI: http://doi.org/10.4062/biomolther.2017.089

Abstract

Placenta is a special organ that contains many nutrients such as growth factors, minerals, and bioactive peptides. Dipeptides of glycine and leucine are major components of porcine placenta extracts (PPE) that has been used as an alternative of human placenta extracts. In this study, we investigated whether major peptides of PPE, Glycyl-L-Leucine (Gly-Leu), L-Leucyl-Glycine (Leu-Gly), and L-Leucyl-L-Leucine (Leu-Leu), affect skin hydration and elasticity in vitro and in vivo. We found that Gly-Leu and Leu-Gly dipeptides induced the expression of transglutaminase 1 in normal human epidermal keratinocytes (NHEKs) whereas Leu-Leu dipeptides did not. Treatment with Gly-Leu or Leu-Gly significantly increased hyaluronan (HA) synthesis in NHEKs and the upregulation of hyaluronan synthase 2 (HAS2) mRNA level was confirmed. In addition, elastase activity was inhibited in NHEKs treated with Gly-Leu or Leu-Gly dipeptides. Oral administration of Gly-Leu or Leu-Gly dipeptides increased skin hydration and elasticity in UVB-irradiated hairless mice. The significant upregulation of HA in UVB-irradiated hairless mice was observed in response to oral administration of Gly-Leu or Leu-Gly. These results suggest that the major dipeptides of porcine placenta, Gly-Leu and Leu-Gly, are potentially active ingredients for skin moisturization formulations.

Keyword

Gly-Leu; Leu-Gly; Hyaluronan; elasticity; Porcine placenta extract

MeSH Terms

Administration, Oral*
Animals
Dipeptides*
Elasticity*
Glycine*
Humans
Hyaluronic Acid
In Vitro Techniques
Intercellular Signaling Peptides and Proteins
Keratinocytes
Leucine*
Mice
Mice, Hairless*
Minerals
Miners
Pancreatic Elastase
Peptides
Placenta
RNA, Messenger
Skin*
Up-Regulation
Dipeptides
Glycine
Hyaluronic Acid
Intercellular Signaling Peptides and Proteins
Leucine
Minerals
Pancreatic Elastase
Peptides
RNA, Messenger