Dendrobium polysaccharide (DOP) ameliorates the LL-37-induced rosacea by inhibiting NF-κB activation in a mouse model.

BACKGROUND: Rosacea, a common chronic inflammatory skin disease worldwide, is currently incurable with complex pathogenesis. Dendrobium polysaccharide (DOP) may exert therapeutic effects on rosacea via acting on the NF-κB-related inflammatory and oxidative processes. MATERIALS AND METHODS: In this study, an LL-37-induced rosacea-like mouse model was established. HE staining was used to assess the skin lesions, erythema severity scores, pathological symptoms, and inflammatory cell numbers of mice in each group. The inflammation level was quantitatively analyzed using enzyme-linked immunosorbent assay (ELISA) and reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR). The expression levels of TLR4 and p-NF-κB were finally detected. RESULTS: DOP improved skin pathological symptoms of rosacea mice. DOP also alleviated the inflammation of rosacea mice. Moreover, the TLR4/NF-κB pathway was observed to be inhibited in the skin of mice after DOP application. These findings evidenced the anti-inflammatory effects of DOP on the LL-37-induced rosacea mouse model. DOP could inhibit NF-κB activation, suppress neutrophil infiltration, and reduce pro-inflammatory cytokines production, which may be the reason for DOP protecting against rosacea. CONCLUSION: This study may propose an active candidate with great potential for rosacea drug development and lay a solid experimental foundation for promoting DOP application in rosacea therapy.

Association Between Acid-Suppressive Drugs and Risk of Rosacea: Retrospective Study Using the Korean National Health Insurance Service-National Sample Cohort.

BACKGROUND: Rosacea is a common inflammatory skin disease with multiple etiologies. Proton pump inhibitors (PPIs) and histamine-2 receptor antagonists (H2RA) are acid suppressive drugs widely used for gastrointestinal (GI) diseases, and long-term use has been reported to be associated with dysbiosis which is a potential risk for development of rosacea. This study aimed to study the association between rosacea and acid suppressants in the Korean national cohort. METHODS: We used Korean National Health Insurance Service-National Sample Cohort data of 749,166 patients with upper GI diseases between 2001 and 2013. Duration of acid suppressants was compared between patients with and without rosacea together with other sociodemographic characteristics and hazard ratios were estimated. RESULTS: Longer use of acid suppressants was significantly associated with increased risk of rosacea. After adjustment for possible confounders, increased cumulative defined daily dose was significantly associated with risk of rosacea (odds ratio [OR], 1.55; 95% confidence interval [CI], 1.20-2.00; P = 0.001). Other factors significantly associated with risk of rosacea include residing in the rural area (OR, 2.58; 95% CI, 2.18-3.06; P < 0.001), greater Charlson Comorbidity Index score (OR, 1.45; 95% CI, 1.15-1.83; P = 0.002), and comorbidities (malignancy, thyroid disease, and depression). CONCLUSION: Results from our study indicate that H2RA or PPI is associated with the occurrence of rosacea among patients with GI diseases in the Korean population. The risk was increased in dose-dependent manner, even after adjusting for confounding variables. Clinicians should be aware of risks associated with prolonged use of acid suppressive drugs.

Symptomatic dermographism induced by oral minocycline: A report of four cases.

Symptomatic dermographism (SD) is the most common form of chronic inducible urticarias. The etiology of this disease has rarely been reported in the literature. Minocycline is widely used in the treatment of acne, rosacea, and other inflammatory skin diseases. Herein we report four cases of SD onset during minocycline administration. These were young women in their 20s to 30s who were taking minocycline orally for acne vulgaris or rosacea. They all experienced the onset of SD 2-3 weeks after taking the drug, and then the complete disappearance of SD 1 month after stopping the drug. Minocycline was thought to be the culprit drug in these cases as other drugs were ruled out on clinical grounds. Our small series suggests that oral minocycline may induce SD, thus raising the awareness of this association in clinical practice. More research is needed to further confirm this association and reveal the underlying mechanism(s).

Dietary supplementation of n-3 PUFAs ameliorates LL37-induced rosacea-like skin inflammation via inhibition of TLR2/MyD88/NF-κB pathway.

Rosacea is a facial chronic inflammatory skin disease with dysfunction of immune and neurovascular system and treatments for rosacea are challenging. N-3 polyunsaturated fatty acids (PUFAs), one of essential fatty acids, are needed for health maintenance and exert anti-inflammation and immunomodulatory effects in a series of cutaneous diseases such as atopic dermatitis and photoaging through dietary supplementation. However, the role of n-3 PUFAs on rosacea remains to be elucidated. In this study, KEGG enrichment analysis and GO analysis indicated that the biological process and signaling pathways, including chemokine signaling pathway, regulated by n-3 PUFAs highly overlapped with those in the pathogenic biological process of rosacea, especially the erythema telangiectasia type. Next, mice were randomized to fed with a customized n-3 PUFAs diet. We showed that n-3 PUFAs ameliorated skin erythema, inhibited dermal inflammatory cell infiltration (mast cells, neutrophils, and CD4 +T cells) and suppressed elevated pro-inflammatory cytokines in LL37-induced rosacea-like mice. Besides, n-3 PUFAs were also verified to repress angiogenesis in LL37-induced mice skin. Further investigation revealed that n-3 PUFAs attenuated LL37-induced inflammation via TLR2/ MyD88/ NF-κB pathway both in mice and in keratinocytes. In conclusion, our findings underscore that dietary supplementation of n-3 PUFAs have the potential to become an efficient and safe clinical therapeutic candidate for rosacea.

Celastrol inhibits LL37-induced rosacea by inhibiting Ca2+/CaMKII-mTOR-NF-κB activation.

Rosacea is a common chronic facial inflammatory disease that affects millions of people worldwide. Due to the unclear etiology of rosacea, effective treatments are limited. Celastrol, a plant-derived triterpene, has been reported to alleviate inflammation in various diseases. However, whether celastrol exerts protective effects in rosacea remains to be elucidated. In this study, weighted gene co-expression network analyses (WGCNA) were performed. Hub modules closely related to rosacea clinical characteristics were identified and found to be involved in inflammation- and angiogenesis-related signaling pathways. Then, the pharmacological targets of celastrol were predicted using the TargetNet and Swiss Target Prediction databases. A GO analysis indicated that the biological process regulated by celastrol highly overlapped with the pathogenic biological processes in rosacea. Next, we showed that celastrol ameliorated erythema, skin thickness and inflammatory cell infiltration in the dermis of LL37-treated mice. Celastrol suppressed the expression of rosacea-related inflammatory cytokines and inhibited the Th17 immune response and cutaneous angiogenesis in LL37-induced rosacea-like mice. We further demonstrated that celastrol attenuated LL37-induced inflammation by inhibiting intracellular-free calcium ([Ca2+]i)-mediated mTOR signaling in keratinocytes. Chelating intracellular Ca2+ with BAPTA/AM potentiated celastrol-induced repression of LL37-induced p-S6 elevation. The mTOR agonist MHY1485 dramatically reinforced LL37-induced rosacea-like characteristics, while celastrol attenuated these outcomes. Moreover, celastrol inhibited LL37-activated NF-κB in a mTOR signaling-dependent manner. In conclusion, our findings underscore that celastrol may be a rosacea protective agent by inhibiting the LL37-activated Ca2+/CaMKII-mTOR-NF-κB pathway associated with skin inflammation disorders.

Topical calcineurin inhibitors as a double-edged sword in rosacea: A systematic review.

BACKGROUND: Rosacea is a chronic inflammatory disease mainly with skin or ocular manifestations. Topical calcineurin inhibitors, pimecrolimus and tacrolimus, can be used to treat rosacea. However, they can also induce rosacea-like eruptions. AIMS: This study systematically reviewed the double-edged sword effects of pimecrolimus and tacrolimus on rosacea. METHODS: Four databases were retrieved to search for articles on the effects of pimecrolimus and tacrolimus on rosacea, including Cochrane Library, Embase, PubMed, and Web of Science. Only English articles were included in the systematic review. Relevant data were collected, and the levels of evidence were evaluated. RESULTS: 28 articles published between 2001 and 2016 were included. 11 articles were about pimecrolimus as the treatment of rosacea, 4 articles were about the pimecrolimus-induced rosacea, 9 articles were about tacrolimus as the treatment of rosacea, and 4 articles were about tacrolimus-induced rosacea. Participants for each study ranged from 1 to 200. Several types of outcome measurements were used for these publications. CONCLUSIONS: Both pimecrolimus and tacrolimus might have double-edged sword effects on rosacea. Pimecrolimus and tacrolimus could be effective for rosacea. However, both of them could also induce rosacea. Larger, randomized, controlled studies on pimecrolimus and tacrolimus as the treatment of rosacea and studies on the mechanisms of pimecrolimus and tacrolimus in treating or inducing rosacea are needed. This systematic review emphasized the double-edged sword role of topical calcineurin inhibitors in rosacea, which may pave the way for future research.

Papulopustular rosacea during nivolumab therapy of metastatic squamous cell esophageal carcinoma.

We present a 76-year old man who developed papulopustular rosacea after receiving nivolumab treatment for his esophageal carcinoma, metastatic to the lungs. Nivolumab is an emerging cancer therapy whose immune-related adverse events are still not fully recognized and likely underreported. The treatment has been reported to cause a myriad of cutaneous immune-related adverse events. However, nivolumab-induced-papulopustular rosacea has been scarcely reported. Thus, this case presents a clinically important finding that physicians should be aware of when seeing patients on nivolumab therapy.

Aspirin alleviates skin inflammation and angiogenesis in rosacea.

Rosacea is a chronic, relapsing inflammatory skin disease featured by abnormal activation of immune responses, vascular dysfunction and prominent permeability barrier alterations. Aspirin, as the first nonsteroidal anti-inflammatory drug (NSAID), is widely used for various inflammatory conditions due to its anti-inflammatory and anti-angiogenic properties. However, its effects on rosacea are unclear. In this study, we demonstrated that aspirin dramatically improved pathological phenotypes in LL37-induced rosacea-like mice. The RNA-sequencing analysis revealed that aspirin alleviated rosacea-like skin dermatitis mainly via modulating immune responses. Mechanically, we showed that aspirin decreased the production of chemokines and cytokines associated with rosacea, and suppressed the Th1- and Th17-polarized immune responses in LL37-induced rosacea-like mice. Besides, aspirin administration decreased the microvessels density and the VEGF expression in rosacea-like skin. We further demonstrated that aspirin inhibited the activation of NF-κB signaling and the release of its downstream pro-inflammatory cytokines. Collectively we showed that aspirin exerts a curative effect on rosacea by attenuating skin inflammation and angiogenesis, suggesting a promising therapeutic candidate for the treatment of rosacea.

Antimicrobial Peptide LL-37 Drives Rosacea-Like Skin Inflammation in an NLRP3-Dependent Manner.

Rosacea is a chronic inflammatory skin disease characterized by immune response-dependent erythema and pustules. Although the precise etiology of rosacea remains elusive, its pathogenesis is reportedly associated with an increased level of antimicrobial peptide LL-37. However, molecular mechanisms underlying the progression of rosacea via LL-37 remain poorly understood. Here, we examined the potential role of LL-37 in rosacea-like skin inflammatory phenotypes at a molecular level. Our in vitro data demonstrated that LL-37 promotes NLRP3-mediated inflammasome activation in lipopolysaccharide-primed macrophages, indicated by the processing of caspase-1 and IL-1ß. LL-37 was internalized into the cytoplasm of macrophages through P2X7 receptor-mediated endocytosis. Intracellular LL-37 triggered the assembly and activation of NLRP3-ASC inflammasome complex by facilitating lysosomal destabilization. Consistent with these in vitro results, intradermal LL-37 administration induced in vivo caspase-1 activation and ASC speck formation in the skin of Nlrp3-expressing, but not in Nlrp3-deficient, mice. Intradermal injection of LL-37 elicited profound recruitment of inflammatory Gr1+ cells and subsequent skin inflammation. However, LL-37-induced rosacea-like skin inflammation was significantly abrogated in Nlrp3-deficient mice. Furthermore, an NLRP3-specific inhibitor, MCC950, markedly reduced LL-37-triggered rosacea-like phenotypes. Taken together, our findings clearly indicate that NLRP3 inflammasome activation plays a crucial role in LL-37-induced skin inflammation and rosacea pathogenesis.

[Granulomatous rosacea-like dermatitis under therapy with tofacitinib]. / Granulomatöse rosazeaartiges Exanthem unter Tofacitinib.

The case of a 32-year-old female with ulcerative colitis who developed severe papulopustular dermatitis while undergoing treatment with the Janus kinase (JAK) inhibitor tofacitinib. Despite intensive topical therapy, treatment with oral corticosteroids and oral doxycycline was unable to achieve sufficient improvement. Hence, tofacitinib treatment needed to be discontinued. It is well known that the class of JAK inhibitors can cause infectious and allergic cutaneous side effects. However, sterile papulopustular dermatitis as a side-effect has rarely been reported to date.