Abstract:
BACKGROUND : Atopic dermatitis (eczema) is an inflammatory skin condition with synthetic treatments that induce adverse effects and
are ineffective. One of the proposed causes for the development of the condition is the outside-in hypothesis, which states that eczema
is caused by a disruption in the skin barrier. These disruptions include developing dry cracked skin, which promotes the production of
histamine. Bulbine frutescens (BF) is traditionally used to treat wounds and eczema; however, limited research has been conducted to
scientifically validate this. Furthermore, gold nanoparticles (AuNPs) have been used to repair damaged skin; however, no research has
been conducted on AuNPs synthesized using BF.
PURPOSE : The study aimed to determine whether BF alleviated skin damage through wound healing, reducing the production of
histamine and investigate whether AuNPs synthesized using BF would enhance biological activity.
METHODS : Four extracts and four synthesized AuNPs were prepared using BF and their antiproliferative and wound healing properties
against human keratinocyte cells (HaCaT) were evaluated. Thereafter, the selected samples antiproliferative activity and antihistamine
activity against phorbol 12-myristate 13-acetate (PMA) stimulated granulocytes were evaluated.
RESULTS : Of the eight samples, the freeze-dried leaf juice (BFE; p < 0.01) extract and its AuNPs (BFEAuNPs; p < 0.05) displayed
significant wound closure at 100 μg/mL and were further evaluated. The selected samples displayed a fifty percent inhibitory
concentration (IC50) of >200 μg/mL against PMA stimulated granulocytes. Compared to the untreated (media with PMA) control
(0.30 ± 0.02 ng/mL), BFEAuNPs significantly inhibited histamine production at a concentration of 100 (p < 0.01) and 50 μg/mL
(p < 0.001).
CONCLUSION : BFE and BFEAuNPs stimulated wound closure, while BFEAuNPs significantly inhibited histamine production. Further
investigation into BFEAuNPs in vivo wound healing activity and whether it can target histamine-associated receptors on mast cells as
a potential mechanism of action should be considered.
