Extract of Emblica officinalis enhances the growth of human keratinocytes in culture

Abstract

Objective

Keratinocytes are the predominant cell type in the epidermis and play key roles in epidermal function. Thus, identification of the compounds that regulate the growth of keratinocytes is of importance. Here we searched for such compounds from the herbs used in traditional medicine Ayurveda.

Methods

Human keratinocytes were cultured in the presence or absence of the herbal extracts for 2 weeks; the effect of the extracts on cell growth was determined by staining the cells with Coomassie brilliant blue. To detect the compounds that regulate the growth of keratinocytes, the herbal extracts were subjected to high-performance liquid chromatography (HPLC).

Results

We found that the extract of Emblica officinalis enhanced the growth of keratinocytes in culture. Further, we fractionated the extract of E. officinalis using HPLC and identified the fractions responsible for the enhanced growth of keratinocytes.

Conclusion

The extract of E. officinalis enhanced the growth of human keratinocytes in culture. E. officinalis contains the compounds that would be beneficial for human skin health because enhanced growth of keratinocytes would promote wound healing.

Introduction

Ayurveda is a traditional medical system from the Indian subcontinent. Many kinds of natural products, including herbs, have been used for the treatment and prevention of diseases in this system. Thus, herbs used in Ayurveda are likely to contain various compounds beneficial to human health. However, the molecular mechanisms for the beneficial effects of these herbs on human health and the compounds responsible for their effects are largely undetermined. If the beneficial functions of the herbs can be analyzed with a simple assay system in vitro, identification of their effective compounds would be greatly facilitated.

The skin is the largest organ in the human body and is composed of two main layers: the epidermis and the dermis. Keratinocytes are the predominant cell type in the epidermis; they proliferate at the basal membrane and migrate upward to form the epidermal surface. Keratinocytes play crucial roles in epidermal functions, forming a mechanical barrier, defense against pathogens and resistance to water loss. Since enhanced growth of keratinocytes may promote wound healing, it could be beneficial for human health [1]. Thus, identification of the compounds that regulate the growth of keratinocytes is of importance.

Based on the above, we screened Ayurvedic herbs for compounds that regulate the growth of human keratinocytes in culture. Afterwards, it was found that the extract of fruit from Emblica officinalis enhanced the growth of keratinocytes. E. officinalis, which is also known as Phyllanthus emblica, Amla or Amalaki, is a tree of 8–18 m in height and is widely distributed in tropical and subtropical areas. E. officinalis is one of the most well-known herbs used in Ayurveda and is reported to provide a variety of benefits to human health [2]. For instance, E. officinalis shows antioxidant [3], [4], [5], antidiabetic [6], antihyperlipidemic [7], antitumor [8], antimutagenic [9], hepatoprotective [10], cardioprotective [11], renoprotective [12], cognitive improvement [13], anti-inflammatory [14], antimicrobial [15], wound healing [16] and derma protective properties [17]. To understand the growth-stimulatory property of E. officinalis in keratinocytes, we analyzed the extract of E. officinalis by chromatographic fractionation, and identified the fractions responsible for the enhanced growth of keratinocytes.