Acne is a chronic
skin disease that typically occurs in the teens and twenties, and its symptoms vary according to age, sex, diet, and lifestyle. The condition is characterized by hyperproliferation of keratinocytes in the epidermis, sebum overproduction, excessive growth of Propionibacterium acnes, and P. acnes-induced skin
inflammation.
Interleukin (IL)-1α and
IL-6 are predominant in the inflammatory lesions of
acne vulgaris. These
cytokines induce an inflammatory reaction in the skin in the presence of pathogens or stresses. Moreover, IL-1α accelerates the production of
keratin 16, which is typically expressed in wounded or aberrant skin, leading to abnormalities in architecture and hyperkeratinization.
Orobol (3',4',5,7-tetrahydroxyisoflavone) is a metabolite of
genistein that inhibited the P. acnes-induced increases in
IL-6 and IL-1α levels in human keratinocytes (HaCaTs) more effectively compared with
salicylic acid. In addition,
orobol decreased the IL-1α and
IL-6 mRNA levels and inhibited the phosphorylation of inhibitor of kappa-B
kinase, nuclear factor of kappa light
polypeptide gene enhancer in B-cells inhibitor, alpha, and
mitogen-activated protein kinase induced by P. acnes. Finally, the expression of Ki67 was decreased by
orobol. Thus,
orobol ameliorated the
inflammation and hyperkeratinization induced by heat-killed P. acnes and thus has potential for use in functional foods and
cosmetics.