Method for screening candidate compounds for preventing and/or attenuating skin aging, and/or for hydrating the skin

Abstract

The disclosure relates to the identification and the use of compounds which regulate the expression of at least one Sestrin gene, for preventing and/or attenuating skin ageing, and/or for hydrating the skin and/or for regulating skin pigmentation. The method includes the following steps: a. bringing at least one test compound in contact with a sample of human keratinocytes or melanocytes; b. measuring the expression of at least one Sestrin gene chosen from SESN3, SESN2 and SESN1 in the keratinocytes or melanocytes; c. selecting the compounds for which an activation of at least 1.6 fold of the expression of at least one of the genes is measured in the keratinocytes treated in a. compared with the untreated keratinocytes, or for which a significant modulation of the expression of at least one of the genes is measured in the melanocytes treated in a. compared with the untreated melanocytes.

1 . In vitro method for screening candidate compounds for preventing and/or attenuating skin ageing, and/or for hydrating the skin, comprising the following steps:
 a. bringing at least one test compound in contact with a sample of human keratinocytes;   b. measuring the expression of at least one Sestrin gene chosen from SESN3, SESN2 and SESN1 in said keratinocytes;   c. selecting the compounds for which an increase of at least 1.6 fold of the expression of at least one of said genes is measured in the keratinocytes treated in a. compared with the untreated keratinocytes.   
     
     
         2 . Method according to  claim 1 , wherein step b. is performed before and after step a. 
     
     
         3 . Method according to  claim 1 , wherein it comprises the following steps:
 a′. preparing at least two samples of human keratinocytes;   a. bringing one of the samples into contact with at least one test compound; then   b. measuring the expression of at least one Sestrin gene in said samples; and   c. selecting the compounds for which an increase of at least 1.6 fold of the expression of at least one of said genes is measured in the keratinocytes treated in a. as compared to the untreated keratinocytes.   
     
     
         4 . Method according to  claim 1 , wherein the expression of at least one Sestrin gene is measured by quantifying the mRNA of the corresponding gene or by quantifying the protein encoded by the corresponding gene. 
     
     
         5 . Method according to  claim 1 , wherein the test compounds are chosen from chemical products or botanical extracts. 
     
     
         6 . Method according to  claim 1 , wherein the increase of the expression of at least one of said genes measured in step c. is of at least 2 fold as compared to untreated keratinocytes.