A biochemical and cellular approach to explore the antiproliferative and prodifferentiative activity of Aloe arborescens leaf extract.

Aloe arborescens Miller, belonging to the Aloe genus (Liliaceae family), is one of the main varieties of Aloe used worldwide. Although less characterized than the commonest Aloe vera, Aloe arborescens is known to be richer in beneficial phytotherapeutic, anticancer, and radio-protective properties. It is commonly used as a pharmaceutical ingredient for its effect in burn treatment and ability to increase skin wound healing properties. However, very few studies have addressed the biological effects of Aloe at molecular level. The aim of the research is to provide evidences for the antiproliferative properties of Aloe arborescens crude leaf extract using an integrated proteomic and cellular biological approach. We analysed the composition of an Aloe arborescens leaf extract by gas chromatography-mass spectrometry analysis. We found it rich in Aloe-emodin, a hydroxylanthraquinone with known antitumoral activity and in several compounds with anti-oxidant properties. Accordingly, we show that the Aloe extract has antiproliferative effects on several human transformed cell lines and exhibits prodifferentiative effects on both primary and immortalized human keratinocyte. Proteomic analysis of whole cell extracts revealed the presence of proteins with a strong antiproliferative and antimicrobial activity specifically induced in human keratinocytes by Aloe treatment supporting its application as a therapeutical agent.