J Dermatol. 2024 Aug 10. doi: 10.1111/1346-8138.17411. Online ahead of print. ABSTRACT Rosacea is a chronic inflammatory disorder primarily affecting the facial skin, prominently involving the cheeks, nose, chin, forehead, and periorbital area. Cutaneous manifestations encompass persistent facial erythema, phymas, papules, pustules, telangiectasia, and flushing. The pathogenesis of rosacea is associated with various exacerbating or triggering factors, including microbial infestation, temperature fluctuations, sunlight exposure, physical exertion, emotional stress, consumption of hot beverages and spicy foods, and exposure to airborne pollen. These environmental factors interact with genetic predispositions in the development of rosacea. The roles of the lipophilic microbiome, ultraviolet radiation, nociceptive responses, and vascular alterations have been proposed as significant factors in the pathogenesis. These insights contribute to understanding the anatomical specificity of facial involvement and the progressive nature of rosacea. East Asian skin, predominantly classified as Fitzpatrick skin phototypes III to IV, is characterized by relatively diminished skin barrier function and increased sensitivity to irritants. Airborne pollen exposure may particularly act as a trigger in East Asian individuals, possibly mediated through toll-like receptors. The lack of specificity in objective clinical and histopathological findings leads to diagnostic challenges for individuals with colored skin, including East Asians, particularly when erythema is the sole objective manifestation. An alternative diagnostic scheme may thus be necessary. A diagnostic approach emphasizing vascular manifestations and nociceptive symptoms potentially holds promise for individuals with darker skin tones. More research focusing on potential variations in skin physiology across different racial groups is essential to establish more effective diagnostic schemes applicable to both dark and light skin colors. PMID:39126257 | DOI:10.1111/1346-8138.17411 {url} = URL to article

Indian J Dermatol. 2024 May-Jun;69(3):232-237. doi: 10.4103/ijd.ijd_470_23. Epub 2024 Jun 26. ABSTRACT BACKGROUND: Rosacea is a chronic inflammatory skin disease. Previous studies have determined that IL-36, IL-37, and IL-38 may play a role in the pathogenesis of various inflammatory diseases. AIMS AND OBJECTIVES: The present study aims to evaluate the relationship of these cytokines with rosacea. MATERIALS AND METHODS: A total of 100 individuals, including 50 patients with rosacea and 50 healthy controls, were included in the study. IL-36, IL-37, and IL-38 levels were measured using the ELISA method by taking serum samples from all participants. RESULTS: The mean serum levels of IL-36, IL-37, and IL-38 in the patient group were 52.17 ± 24.07 pg/ml, 18.46 ± 8.18 pg/ml, and 25.74 ± 8.36 ng/l, respectively. The mean serum levels of IL-36, IL-37, and IL-38 in the control group were 32.99 ± 19.90 pg/ml, 44.61 ± 22.27 pg/ml, and 45.61 ± 17.32 ng/l, respectively. The difference between the serum levels of IL-36, IL-37, and IL-38 in the patient and control groups was statistically significant (P < 0.001). CONCLUSION: Based on these findings, an increase in IL-36 and a decrease in IL-37 and IL-38 may contribute to the pathogenesis of rosacea. Future rosacea treatments could target and/or interact with these possible steps in the pathogenesis of rosacea. PMID:39119329 | PMC:PMC11305503 | DOI:10.4103/ijd.ijd_470_23 {url} = URL to article

Skin Res Technol. 2024 Aug;30(8):e13875. doi: 10.1111/srt.13875. ABSTRACT BACKGROUND: Recent studies increasingly suggest that microbial infections and the immune responses they elicit play significant roles in the pathogenesis of chronic inflammatory skin diseases. This study uses Mendelian randomization (MR) and Bayesian weighted Mendelian randomization (BWMR) to explore the causal relationships between immune antibody responses and four common skin diseases: psoriasis, atopic dermatitis (AD), rosacea, and vitiligo. METHODS: We utilized summary statistics from genome-wide association studies (GWAS) for antibody responses to 13 infectious pathogens and four skin diseases. Single nucleotide polymorphisms (SNPs) were selected as instrumental variables (IVs) to assess causal relationships using multiple MR methods, including inverse variance weighted (IVW), MR Egger, and weighted median. BWMR was also employed to confirm findings and address potential pleiotropy. RESULTS: The IVW analysis identified significant associations between specific antibody responses and the skin diseases studied. Key findings include protective associations of anti-Epstein-Barr virus (EBV) IgG seropositivity and Helicobacter pylori UREA antibody levels with psoriasis and AD. anti-chlamydia trachomatis IgG seropositivity, anti-polyomavirus 2 IgG seropositivity, and varicella zoster virus glycoprotein E and I antibody levels were negatively associated with rosacea, while EBV Elevated levels of the early antigen (EA-D) antibody levels and HHV-6 IE1B antibody levels were positively associated with rosacea. H. pylori Catalase antibody levels were protectively associated with vitiligo, whereas anti-herpes simplex virus 2 (HSV-2) IgG seropositivity was positively associated with vitiligo. The BWMR analysis confirmed these associations. CONCLUSION: This study underscores the significant role of H. pylori and other pathogens in these skin diseases, suggesting both protective and exacerbating effects depending on the specific condition. Understanding these pathogen-immune interactions can lead to the development of more effective, personalized treatments and preventative strategies, ultimately improving patient outcomes and quality of life. PMID:39120064 | PMC:PMC11311118 | DOI:10.1111/srt.13875 {url} = URL to article

J Invest Dermatol. 2024 Aug 7:S0022-202X(24)01982-1. doi: 10.1016/j.jid.2024.07.018. Online ahead of print. ABSTRACT Numerous recent evidence highlights epidemiological connections between rosacea and metabolic disorders. However, the precise path through which metabolic factors impact rosacea risk is still unclear. Therefore, this study aims to investigate the role of adiponectin, a crucial adipokine that regulates metabolic homeostasis, in the pathogenesis of rosacea. We elucidated a detrimental feedback loop between rosacea-like skin inflammation and decreased levels of skin adiponectin. To elaborate, rosacea lesional skin exhibits diminished adiponectin expression compared to non-lesional areas in the same patients. Induction of rosacea-like inflammation reduced adiponectin levels in the skin by generating inflammatory cytokines that suppress adiponectin production from subcutaneous adipocytes. Conversely, complete depletion of adiponectin exacerbated rosacea-like features in the mouse model. Mechanistically, adiponectin deficiency led to heightened S6 phosphorylation, a marker of the mTORC1 signaling pathway, in the epidermis. Adiponectin significantly inhibited S6 phosphorylation in cultured keratinocytes. Notably, replenishing adiponectin whole protein or topically applying an agonist for adiponectin receptor 1 successfully improved rosacea-like features in mice. This study contributes to understanding the role of adiponectin in skin inflammation associated with rosacea pathophysiology, suggesting that restoring adiponectin function in the skin could be a potential therapeutic strategy. PMID:39122145 | DOI:10.1016/j.jid.2024.07.018 {url} = URL to article

Cutan Ocul Toxicol. 2024 Aug 8:1-5. doi: 10.1080/15569527.2024.2383242. Online ahead of print. ABSTRACT BACKGROUND/ OBJECTIVES: Rosacea is a common chronic inflammatory skin disorder. Endocrinedisrupting chemicals (EDC) are toxic substances, that may gain entry through the skin and subsequently interfere with hormonal and immune functions. Bisphenol A (BPA) and pentachlorophenol sodium (PCS) are two of these EDCs, incriminated in the pathogenesis of certain inflammatory skin disorders. We aimed to test the hypothesis that exposure to BPA and PCS might be involved in the pathogenesis of rosacea. METHODS: This prospective cross-sectional study involved 34 patients with rosacea (18F/16 M; mean age 48.5 ± 11 years) and 34 age and sex-matched healthy controls (20 F/14 M; mean age 48.2 ± 10.2 years). Main anthropometric measures, fasting plasma glucose (FPG), insulin, HOMA-IR, lipids, C-reactive protein (CRP), BPA, and PCS levels were quantified and recorded. RESULTS: Serum CRP (9.6 ± 3.4 vs. 3.7 ± 1.6 mg/L, respectively, p0.05 for all). Serum BPA levels were 55.8 ± 14.4 and 51.9 ± 19.2 ng/mL, and PCS levels were 63.3 ± 45.9 ng/mL and 68.6 ± 40.8 ng/mL for patients and healthy controls, respectively. There was no significant difference in BPA and PCS levels between the two groups (p > 0.05 for both). No significant association was found among HOMAIR, CRP, BPA, and PCS levels (p > 0.05 for all). CONCLUSIONS: Although the present study fails to provide presumptive evidence for the role of BPA and PCS in rosacea, the question as to other EDCs might be involved in its etiopathogenesis remains. This hypothesis requires confirmation in large-scale future prospective trials. PMID:39113570 | DOI:10.1080/15569527.2024.2383242 {url} = URL to article