Unveiling the Ability of Witch Hazel (Hamamelis virginiana L.) Bark Extract to Impair Keratinocyte Inflammatory Cascade Typical of Atopic Eczema

Abstract

Hamamelis virginiana L. bark extract is a traditional remedy for skin affections, including atopic dermatitis/eczema (AD). Hamamelis preparations contain tannins, including hamamelitannin (HT), although their pharmacological role in AD is still unknown. This study aimed to study the rational for its topical use by considering the impact of crucial biomarkers on AD pathogenesis. A standardized extract (HVE) (0.5–125 μg/mL) was compared to hamamelitannin (HT), its main compound (0.5–5 μg/mL), in a model of human keratinocytes (HaCaTs), challenged with an AD-like cytokine milieu (TNF-α, IFN-γ, and IL-4). HVE inhibited the release of mediators involved in skin autoimmunity (IL-6 and IL-17C) and allergy (TSLP, IL-6, CCL26, and MMP-9) with a concentration-dependent fashion (IC50s < 25 μg/mL). The biological mechanism was ascribed, at least in part, to the impairment of the NF-κB-driven transcription. Moreover, HVE counteracted the proliferative effects of IL-4 and recovered K10, a marker of skin differentiation. Notably, HT showed activity on well-known targets of IL-4 pathway (CCL26, K10, cell proliferation). To the best of our knowledge, this work represents the first demonstration of the potential role of Hamamelis virginiana in the control of AD symptoms, such as itch and skin barrier impairment, supporting the relevance of the whole phytocomplex.

Ginnalin A and hamamelitannin: the unique gallotannins with promising anti-carcinogenic potential

“…Similarly, HAM was also reported to be an anticancer, anti-inflammatory, antioxidant agent as well as a quorum sensing inhibitor as established in earlier studies in the literature [25][26][27][28][29][30][31]. It was observed in a study that HAM possessed anti-colon cancer activities as it showed lower IC 50 values against various colorectal cell lines in MTT assay.…”

“…In another set of experiments, HAM was found to be active against chemokine (C-C motif) ligand 26 (CCL26), K10, and cell proliferation and hence hindered the interleukin-4 (IL-4) inflammatory pathway. Thus, it was found to be effective against the keratinocyte inflammatory cascade [ 28 ]. In yet another set of experiments, the murine skin fibroblasts were exposed to ultraviolet (UV)-B (UVB) radiation.…”

Hydrolyzable Tannins in the Management of Th1, Th2 and Th17 Inflammatory-Related Diseases

“…Recently, our group of researchers attributed an anti-inflammatory activity to a polar extract from witch hazel bark and twigs (0.5–125 μg/mL) in HaCaT cells challenged with TNF-α and IL-4 [ 52 , 84 ]. The extract was characterized by the presence of oligomeric proanthocyanidins (0.29%) and hamamelitannin (0.30%) as the main compounds.…”

Evidenz- und erfahrungsbasierte Phytotherapie bei Erkrankungen der Haut

“…Der Extrakt hemmte sowohl die Freisetzung von Mediatoren, die an der Haut Autoimmungeschehen vermitteln (IL-6 und IL-17C), als auch solche, die allergische Reaktionen auslösen (TSLP, IL-6, CCL26 und MMP-9). Zudem wirkte er der proliferativen Wirkung von IL-4 entgegen und regenerierte K10, einen Marker für die Hautdifferenzierung, was die positive Wirkung von Hamamelis bei Juckreiz und Beeinträchtigung der Hautbarriere erklärt [23].…”