Causal relationship between gut microbiota and pathological scars: a two-sample Mendelian randomization study.

Background: Pathological scars, including keloids and hypertrophic scars, represent a significant dermatological challenge, and emerging evidence suggests a potential role for the gut microbiota in this process. Methods: Utilizing a two-sample Mendelian randomization (MR) methodology, this study meticulously analyzed data from genome-wide association studies (GWASs) relevant to the gut microbiota, keloids, and hypertrophic scars. The integrity and reliability of the results were rigorously evaluated through sensitivity, heterogeneity, pleiotropy, and directionality analyses. Results: By employing inverse variance weighted (IVW) method, our findings revealed a causal influence of five bacterial taxa on keloid formation: class Melainabacteria, class Negativicutes, order Selenomonadales, family XIII, and genus Coprococcus2. Seven gut microbiota have been identified as having causal relationships with hypertrophic scars: class Alphaproteobacteria, family Clostridiaceae1, family Desulfovibrionaceae, genus Eubacterium coprostanoligenes group, genus Eubacterium fissicatena group, genus Erysipelotrichaceae UCG003 and genus Subdoligranulum. Additional sensitivity analyses further validated the robustness of the associations above. Conclusion: Overall, our MR analysis supports the hypothesis that gut microbiota is causally linked to pathological scar formation, providing pivotal insights for future mechanistic and clinical research in this domain.

Effects of 15% Azelaic Acid Gel in the Management of Post-Inflammatory Erythema and Post-Inflammatory Hyperpigmentation in Acne Vulgaris.

INTRODUCTION: The aim of this study was to assess the efficacy and safety of 15% azelaic acid (AzA) gel in treating acne-induced post-inflammatory erythema (PIE) and post-inflammatory hyperpigmentation (PIH). The effects of 15% AzA gel on acne, skin barrier function, and quality of life were also evaluated. METHODS: A total of 72 patients with mild to moderate acne were enrolled in a randomized, double-blind, placebo-controlled trial. Patients were divided into two groups: patients in the AzA group applied 15% AzA gel twice daily for 12 weeks, and those in the placebo group applied AzA-free gel. Clinical evaluations using non-invasive skin detection technologies, including VISIA skin analysis, dermoscopy, and skin physiological function tests, were performed at 0, 4, 8, and 12 weeks. Main outcome measures included the post-acne hyperpigmentation index (PAHPI), melanin, hemoglobin, individual typology angle, water content, transepidermal water loss, and sebum. Investigator Global Assessment) and Dermatology Life Quality Index (DLQI) assessments were conducted at weeks 0 and 12. Adverse reactions were recorded. RESULTS: Of the 72 patients at study initiation, 60 completed the trial. At 8 and 12 weeks, patients in the AzA group showed significantly reduced PAHPI for PIE lesions compared to baseline and patients receiving placebo (P < 0.05). Patients in both groups exhibited reduced PIH lesions at weeks 8 and 12 that differed significantly from baseline (P < 0.05). Hemoglobin content decreased significantly in AzA-treated PIE lesions compared to those treated with placebo at week 12 (P < 0.05). Melanin content decreased significantly in AzA-treated PIH lesions at week 12 (P < 0.05). The AzA group showed higher improvement in DLQI (P < 0.05), and greater overall satisfaction (P < 0.05) compared to placebo. CONCLUSION: The results indicate that 15% AzA gel effectively improved acne-induced PIE and PIH with minimal adverse reactions, making it a viable clinical application. In the study population, it had no adverse effects on skin barrier function and contributed positively to acne improvement and patient quality of life. TRIAL REGISTRATION: This study was registered with the Chinese Clinical Trial Registry (ChiCTR.org.cn) under the identifier ChiCTR2300076959. The registration date was 25 October 2023, retrospectively registered.

Overexpression and potential roles of midkine via regulation of vascular endothelial growth factor A in psoriasis.

Midkine plays a critical role in angiogenesis by regulating the vascular endothelial growth factor (VEGF) signalling pathway, which is known to be associated with psoriasis pathogenesis. However, research on midkine-psoriasis relationship remains limited. The objective of this study was to detect midkine expression in psoriasis and investigate its potential role in the disease. Midkine expression was measured using immunohistochemistry and ELISA. Effects of midkine on HaCaT cell proliferation, VEGF-A production and signalling pathways were assessed using CCK8, RT-PCR and WB. Scratch and in vitro tube formation tests were used to evaluate the effects of HaCaT-cell-activated midkine on the migration and tube formation of human dermal microvascular endothelial cells. Murine psoriasiform models were injected with midkine recombinant protein and midkine monoclonal antibody to investigate skin lesions, tissue sections and dermal microvessel density. Levels of midkine significantly increased in both lesions and serum of patients with psoriasis. Serum expression of midkine decreased after treatment and a positive correlation was found between midkine and disease severity. Midkine promoted HaCaT cell proliferation and VEGF-A production. The Notch2/HES1/JAK2-STAT5A pathway expression increased after midkine treatment of HaCaT cells. The supernatant of HaCaT cells treated with midkine promoted HMEC-1 migration and angiogenesis in vitro. Recombinant midkine protein exacerbated psoriasiform lesions with increased expressions of VEGF-A and microvessel density, while midkine monoclonal antibody alleviated psoriasis lesions. Midkine may have a significant impact on psoriasis angiogenesis by regulating VEGF-A expression through the Notch2/HES1/JAK2-STAT5A pathway, highlighting a potential therapeutic target for psoriasis treatment.

Differences in clinical characteristics of rosacea across age groups: A retrospective study of 840 female patients.

BACKGROUND: Aging remains a common influencing factor for many diseases. Previous studies have shown that age is significantly associated with rosacea among female cases and that the incidence of rosacea increases with age. However, previous studies did not specifically analyze the clinical characteristics of different age groups. OBJECTIVE: This study aimed to analyze and compare the clinical characteristics of female patients of rosacea among different age groups. METHODS: We conducted a retrospective study of 840 female rosacea subjects and compared cutaneous features, aggravating factors, systemic diseases, and psychological states across age groups. The patients were divided into three groups according to their age at diagnosis: ≤30 years，31-44 years，and ≥45 years. RESULTS: In our study, the mean age of subjects was 35.9 ± 10.23 years. The common symptoms included telangiectasia (82.6%), persistent erythema (82.0%), burning/stinging sensation (89.3%), dry sensation (74.0%), and pruritis (41.9%). Hot temperature (89.9%), emotional changes (67.3%), spicy food (55.6%), and sun exposure (50.7%) were the common aggravating factors. Some patients had comorbidities of systemic disorders (20.4%). Of the patients, 48.8% presented with anxiety and 35.2% with depression. The clinical characteristics were found to be significantly different among the different age groups. Middle-aged and older patients (≥45 years) were more likely to have more serious persistent erythema and telangiectasia. And these patients were relatively less affected by some of the influencing factors and had more systemic diseases of the digestive system, endocrine metabolic system, and cardiovascular system (p < 0.05). CONCLUSION: We revealed the impact of age on the characteristics of rosacea, which indicated that the clinical features of rosacea are more complex and more difficult to treat in females over the age of 45.