Effekt von Ultraviolett-A-Filtern auf pigmentierte und alternde Haut

Neben der Wirkung von Ultraviolett-A-Filtern beschäftigen wir uns dieses Mal auch mit Therapieansätzen für das bullöse Pemphigoid, eine Autoimmunerkrankung, deren Charakteristika prall gespannte Blasen sowie Autoantikörper gegen Proteine der Hemidesmosomen sind. Und es gehtausserdem um die gestörte Heilung bei infizierten Wunden unter Diabetes mellitus.

The impact of methoxypropylamino cyclohexenylidene ethoxyethyl-cyanoacetate (MCE) UVA1 filter on pigmentary and ageing signs

While sunscreens traditionally focused on UVB protection, recognizing UVA’s harmful effects led to new regulations in Europe mandating a minimum UVA protection factor/SPF ratio of 1/3. However, current sunscreens lack sufficient filters to shield against UVA1 (>370 nm).

A study published in the JEADV assessed the effectiveness and safety of an SPF50 sunscreen with methoxypropylamino cyclohexenylidene ethoxyethylcyano-acetate (MCE) over 8 weeks, with subjects exposed to the sun for 2 hours daily. Comparing it to a reference SPF50 sunscreen without MCE, the study measured skin benefits related to enlarged UVA1 protection. The study demonstrated that the inclusion of MCE providing UVA protection in the 370-400nm range significantly decreases pigmentation and signs of aging compared to the reference product lacking MCE. However, the study had limitations, including the absence of skin phototypes I, V, and VI and the need for further investigation into the efficacy of MCE in diverse populations.

Omalizumab in the treatment of bullous pemphigoid resistant to first-line therapy

Bullous pemphigoid (BP) is a prevalent autoimmune condition posing challenges in treatment due to adverse effects linked with corticosteroids and immunosuppressive therapies. Chebani et al. conducted a nationwide multicenter study in France to assess omalizumab’s safety and efficacy in treating BP, aiming to identify predictors of treatment response. The study, comprising 100 patients across 18 expert departments, found omalizumab – an IgE antagonist – effective in 86% of cases, with 77% achieving complete remission and 9% partial remission.

While some patients required additional therapies, 57% achieved complete remission with minimal treatment, including 49% with omalizumab monotherapy. Omalizumab showed rapid disease control, with a median time to disease activity control of 10 days and to complete remission of 3 months. The safety profile was favorable, with only 4% experiencing related adverse events. Notably, omalizumab occasionally achieved disease control without additional immunosuppressive or immunomodulatory treatments.

The presence of Anti-BP180-NC16A IgE was suggestive of a favorable treatment response, indicating its potential as a standard assessment tool for BP patients. Furthermore, patients previously treated with multiple therapies exhibited a higher complete response rate, suggesting the potential for delayed impacts of immunosuppressive agents and the need for multiple therapies in resistant cases.

Reduced bioactive microbial products (pathogen-associated molecular patterns) contribute to dysregulated immune responses and impaired healing in infected wounds in mice with diabetes

Diabetic foot ulcers contribute to the majority of lower extremity amputations. These ulcers are characterized by persistent and unresolved inflammation. While infections typically hinder wound healing, the presence of low subinfective levels of bacteria can actually expedite the healing process by enhancing inflammatory responses in wounds via the activation of Toll-like receptors (TLRs). A study conducted in a diabetes mouse model showed that, despite higher bacterial levels, infected diabetic wounds early after injury exhibited significantly reduced levels of bioactive lipopolysaccharide (LPS, a bacterial product), leading to decreased expression of Toll-like receptor 4 (TLR4) and lower production of proinflammatory cytokines. Topical treatment with bioactive LPS effectively increased TLR4 expression and cytokine production in diabetic wounds. Importantly, LPS treatment also substantially improved healing and significantly reduced infection burdens of both Pseudomonas aeruginosa and Staphylococcus aureus by 90-95%.

This suggests that LPS treatment holds promise for managing healing and polymicrobial infections in diabetic wounds.