Publications by authors named "Birgit Haarhaus"

We demonstrated the anti-inflammatory and anti-oxidative effects of (HL) extract on solar simulator-irradiated primary human keratinocytes (PHKs) by analyzing ERK and p38 MAPK phosphorylation and production of IL-6 and IL-8. The anti-inflammatory effect of topically applied HL was further tested in vivo on human skin. To this end, we developed an oil-in-water (O/W) and a water-in-oil (W/O) cream with a lipid content of 40%.

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Psoriasis is a chronic inflammatory skin disease characterized by hyperproliferation of keratinocytes and a pro-inflammatory milieu in the skin. While patients with moderate to severe psoriasis are treated using targeted therapies (small molecules and monoclonal antibodies), patients suffering from milder forms are still in need of effective topical products without adverse effects. Antimony compounds (ACs) are regularly used as anti-inflammatory compounds in traditional and anthroposophic medicine and as antiprotozoan drugs.

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Psoriasis is a chronic inflammatory skin disease characterized by hyperproliferation of keratinocytes and expression of pro-inflammatory cytokines in the epidermis. New biological drugs were developed for the systemic treatment of moderate to severe psoriasis. However, products for the topical treatment of mild psoriasis are still required.

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is a bitter herb that is traditionally used to improve gastric disorders. Recently, we have shown that extract (GE) also modulates the lipid metabolism of human keratinocytes in vitro and in vivo. In the present study, we investigated the role of GE on ceramide synthesis in human primary keratinocytes (HPKs) and psoriasis-like keratinocytes.

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Acne is associated with hyperkeratosis, elevated levels of skin sebum and growth of () and (). Furthermore, promotes inflammation by inducing IL-6 production and oxidative stress. The aim of this study was to assess the antioxidant, anti-inflammatory and antibacterial potential of a hop-CO₂-extract with 50% humulone and lupulone.

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is a herbal bitter drug that is used to enhance gastrointestinal motility and secretion. Recently we have shown that amarogentin, a characteristic bitter compound of extract (GE), binds to the bitter taste receptors TAS2R1 and TAS2R38 in human keratinocytes, and stimulates the synthesis of epidermal barrier proteins. Here, we wondered if GE also modulates lipid synthesis in human keratinocytes.

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Ethnopharmacological Relevance: Potentilla erecta (L.) Raeusch is a medicinal plant of the Northern hemisphere belonging to the plant family of roses (Rosaceae). It has traditionally been used to treat inflammatory disorders of the skin and mucous membranes as well as chronic diarrhea.

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Potentilla erecta (PE) is a small herbaceous plant with four yellow petals belonging to the Rosaceae family. The rhizome of PE has traditionally been used as an antidiarrheal, hemostatic and antihemorrhoidal remedy. PE contains up to 20% tannins and 5% ellagitannins, mainly agrimoniin.

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Bitter taste receptors (TAS2Rs) are expressed in mucous epithelial cells of the tongue but also outside the gustatory system in epithelial cells of the colon, stomach and bladder, in the upper respiratory tract, in the cornified squamous epithelium of the skin as well as in airway smooth muscle cells, in the testis and in the brain. In the present work we addressed the question if bitter taste receptors might also be expressed in other epithelial tissues as well. By staining a tissue microarray with 45 tissue spots from healthy human donors with an antibody directed against the best characterized bitter taste receptor TAS2R38, we observed an unexpected strong TAS2R38 expression in the amniotic epithelium, syncytiotrophoblast and decidua cells of the human placenta.

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Keratinocytes express the bitter taste receptors TAS2R1 and TAS2R38. Amarogentin as an agonist for TAS2R1 and other TAS2Rs promotes keratinocyte differentiation. Similarly, mast cells are known to express bitter taste receptors.

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Salicin from willow bark has been used throughout centuries in China and Europe for the treatment of pain, headache, and inflammatory conditions. Recently, it could be demonstrated that salicin binds and activates the bitter taste receptor TAS2R16. Studies on rodent tissues showed the general expression of bitter taste receptors (TAS2Rs) in rodent brain.

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Recent studies have shown that human bitter taste receptors (TAS2Rs) are not only expressed in mucous epithelial cells of the tongue, but also in epithelial cells of the colon, stomach and upper respiratory tract. These cell types come in close contact with external bitter compounds by ingestion or breathing. In the present work we addressed the question whether bitter taste receptors might also be expressed in cornified epithelial cells of the skin.

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Ultraviolet radiation induces DNA damage and oxidative stress which can result in skin inflammation, photoaging, and photocarcinogenesis. The flavonoid luteolin that is present in high amounts in the dyers weld, Reseda luteola, is one of the most potent antioxidative plant metabolites and also has ultraviolet-absorbing properties.The aim of this study was to determine whether tocopherol and ubiquinone add synergistic antioxidative values to luteolin.

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Human skin is continuously exposed to solar radiation, which can result in photoaging, a process involving both dermal and, to a lesser extent, epidermal structures. Previously, we have shown that the flavonoid luteolin protects the epidermis from ultraviolet (UV)-induced damage by a combination of UV-absorbing, antioxidant, and antiinflammatory properties. The aim of the present study was to determine direct and indirect effects of luteolin on dermal fibroblasts as major targets of photoaging.

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