Rosacea is associated with conjoined interactions between physical barrier of the skin and microorganisms: A pilot study

A two-center randomized controlled trial of a repairing mask as an adjunctive treatment for mild to moderate rosacea

OBJECTIVE

To investigate the efficacy and safety of a repairing mask as an adjunctive treatment for skin barrier maintenance of mild to moderate rosacea.

METHODS

Patients with rosacea were recruited in this dual center randomized controlled trial from November 2019 to December 2021. A total of 64 patients were included and randomized into two groups at a ratio of 3:1 into a mask group (n = 47) and a control group (n = 17). Patients in the mask group received treatment with Dr. Yu Centella asiatica repairing facial mask three times weekly for a duration of 6 weeks. All participants were instructed to continue their regimen of 50 mg oral minocycline twice daily and to apply Dr. Yu Intensive Hydrating Soft Cream twice daily. The primary endpoint of this study was the Investigator Global Assessment (IGA) score.

RESULTS

A total of 54 patients completed this trial, with 41 in the mask group and 13 in the control group. After using this facial mask for 3 and 6 weeks, the IGA, facial skin dryness, facial flushing, and severity of skin lesion in the mask group showed significantly improvement (p < 0.05). Moreover, the change in the delta degree of skin flushing was significantly higher than that in the control group (p = 0.037). Throughout the study, no adverse events were reported in either group of participants.

CONCLUSION

The Dr. Yu Centella asiatica repairing facial mask, as an adjunctive treatment of rosacea, appears to effectively repair and protect the skin barrier, alleviate cutaneous symptoms of rosacea, and is both efficacious and safe for patient use.

Rosacea, microbiome and probiotics: the gut-skin axis

Rosacea is an inflammatory skin disease involving diverse symptoms with a variable clinical progress which can severely impact the patient's quality of life as well as their mental health. The pathophysiological model of rosacea involves an unbalanced immune system predisposed to excessive inflammation, in addition to vascular and nervous alterations, being certain cutaneous microorganisms' triggers of the symptoms onset. The gut-skin axis explains a bidirectional interaction between skin and gut microbiota in some inflammatory skin diseases such as atopic dermatitis, psoriasis, or rosacea. The introduction and consolidation of the next-generation sequencing in recent years has provided unprecedented information about the microbiome. However, the characterization of the gut and skin microbiota and the impact of the gut-skin axis in patients with rosacea has been little explored, in contrast to other inflammatory skin diseases such as atopic dermatitis or psoriasis. Furthermore, the clinical evolution of patients with rosacea is not always adequate and it is common for them to present a sustained symptomatology with frequent flare-ups. In this context, probiotic supplementation could improve the clinical evolution of these patients as happens in other pathologies. Through this review we aim to establish and compile the basics and directions of current knowledge to understand the mechanisms by which the microbiome influences the pathogenesis of rosacea, and how modulation of the skin and gut microbiota could benefit these patients.

Rosacea pathogenesis and therapeutics: current treatments and a look at future targets

Rosacea is a chronic inflammatory skin condition associated with a significant health and economic burden from costs and loss of productivity due to seeking medical treatment. The disease encompasses multiple phenotypic manifestations involving a complex and multi-variate pathogenesis. Although the pathophysiology of rosacea is not completely understood, ongoing research is continually elucidating its mechanisms. In this review, current concepts of rosacea pathogenesis will be addressed which involve skin barrier and permeability dysfunction, the innate and adaptive immune systems, and the neurovascular system. More specifically, the cathelicidin pathway, transient potential receptor channels, mast cells, and the NLRP3 inflammasome pathway are various targets of current pharmacologic regimens. Future therapies may seek different mechanisms to act on current treatment targets, like the potential use of JAK/STAT inhibitors in ameliorating skin barrier dysfunction or TLR antagonists in alleviating cathelicidin mediated inflammation. Other potential treatments aim for entirely different molecular targets such as microvesicle particle mediated local and systemic inflammation. Ultimately rosacea is associated with a significant health and economic burden which warrants deeper research into its pathogenesis and resultant new treatment discovery.

Role of the skin microbiota and intestinal microbiome in rosacea

Rosacea is a chronic inflammatory cutaneous disorder of uncertain etiology that mainly affects the centrofacial region, including cheeks, nose, chin, forehead, and eyes. The pathogenesis of rosacea remains unclear because it involves several complex factors. Additionally, the potential treatment methods need to be explored. We reviewed the common bacterial species in the skin microbiota and gut microbiota of rosacea patients such as Demodex folliculorum, Staphylococcus epidermidis, Bacillus oleronius, Cutibacterium acnes, and Helicobacter pylori and identified their role in the pathogenesis. Besides, we summarized the influence factors such as temperature and age on rosacea patients. We also systematically reviewed the commonly used clinical treatment methods, including antibiotics, probiotics. as well as their treatment mechanism and application precautions.

The Fate of Epidermal Tight Junctions in the stratum corneum: Their Involvement in the Regulation of Desquamation and Phenotypic Expression of Certain Skin Conditions

We evaluated the presence of tight junction (TJ) remnants in the stratum corneum (SC) of in vitro reconstructed human epidermis and human skin explants subjected or not to an aggressive topical treatment with beta-lipohydroxy salicylic acid (LSA) for 24 h. LSA-treated samples showed an increased presence of TJ remnants in the two lowermost layers of the SC, as quantified with standard electron microscopy. The topical aggression-induced overexpression of TJ-like cell–cell envelope fusions may influence SC functions: (1) directly, through an enhanced cohesion, and (2) indirectly, by impeding accessibility of peripheral corneodesmosomes to extracellular hydrolytic enzymes and, thus, slowing down desquamation. Observations of ichthyotic epidermis in peeling skin disease (PSD; corneodesmosin deficiency; two cases) and ichthyosis hypotrichosis sclerosing cholangitis syndrome (IHSC/NISCH; absence of claudin-1; two cases) also demonstrated increased persistence of TJ-like intercellular fusions in pathological SC and contributed to the interpretation of the diseases’ pathological mechanisms.

Relationships of Serum Homocysteine, Vitamin B12, and Folic Acid Levels with Papulopustular Rosacea Severity: A Case-Control Study

Background

Rosacea is a chronic inflammatory skin disease with a multifactorial etiology. Recently, associations between serum homocysteine (Hcy) levels and inflammatory skin diseases, such as psoriasis and hidradenitis suppurativa, have been reported. However, no study has explored the levels of serum Hcy, folic acid, and vitamin B₁₂ in patients with rosacea.

Objective

To investigate serum Hcy, vitamin B₁₂, and folic acid levels in patients with papulopustular rosacea (PPR), we characterized the association of these levels with PPR severity.

Methods

This case-control study included 138 PPR patients and 58 healthy controls. The serum levels of Hcy, vitamin B₁₂, and folic acid were measured. A correlation was assessed between disease severity and serum levels of Hcy, vitamin B₁₂, and folic acid.

Results

Serum vitamin B₁₂ and folic acid levels were significantly lower in PPR patients than in the healthy controls (p = 0.011 and p = 0.0173, respectively). Although serum Hcy levels did not significantly differ between PPR patients and healthy controls, PPR severity was positively correlated with serum Hcy levels (p < 0.001).

Conclusions

Our results suggest a possible association between hyperhomocysteinemia and vitamin B₁₂ deficiency in patients with PPR.

Rosacea: Treatment targets based on new physiopathology data

Over the past 15 years, numerous clinical, epidemiological and physiopathological articles have been published on rosacea. There is now increasing evidence that rosacea is an inflammatory disease characterised by abnormal innate immune response, major vascular changes, and increased colonisation by Demodex mites, along with a genetic predisposition and multiple external aggravating factors. It is thus possible to define treatment targets and possible treatments: 1) permanent vascular changes (medical and instrumental treatments); 2) flushing (betablockers, botulinum toxin); 3) innate immunity (antibiotics, nonspecific antioxidants and anti-inflammatory molecules); 4) a neurovascular component (analgesics, antidepressants); 5) Demodex (antiparasitic drugs); 6) microbiome; 7) skin barrier impairment (cosmetics and certain systemic drugs); 8) sebaceous glands (isotretinoin, surgery); 9) environmental factors (alcohol, coffee, UV exposure). Treatment recommendations are now available in many countries and benefit from the new phenotypic approach to rosacea, in which every sign or symptom is considered separately rather than having to deal with overlapping subtypes. Since the 2000s, many good quality clinical trials have been published in the field of rosacea and many others are still ongoing. Rosacea is a complex disease involving many different mechanisms and with numerous possible treatments, but there are still some important unmet needs with regard to optimal care.

The Importance of Assessing Burning and Stinging when Managing Rosacea: A Review

Rosacea, a chronic condition usually recognized by its visible presentation, can be accompanied by invisible symptoms, such as burning and stinging. The aim of this review is to gather the most recent evidence on burning and stinging, in order to further emphasize the need to address these symptoms. Inflammatory pathways can explain both the signs and symptoms of rosacea, but available treatments are still evaluated primarily on their ability to treat visible signs. Recent evidence also highlights the adverse impact of symptoms, particularly burning and stinging, on quality of life. Despite an increasing understanding of symptoms and their impact, the management of burning and stinging as part of rosacea treatment has not been widely investigated. Clinicians often underestimate the impact of these symptoms and do not routinely include them as part of management. Available therapies for rosacea have the potential to treat beyond signs, and improve burning and stinging symptoms in parallel. Further investigation is needed to better understand these benefits and to optimize the management of rosacea.

A randomized, controlled, split-face study of topical timolol maleate 0.5% eye drops for the treatment of erythematotelangiectatic rosacea

BACKGROUND

Centrofacial erythema associated with telangiectasis is the most common presentation of rosacea, known as erythematotelangiectatic rosacea (ETR). However, successful management of these symptoms remains challenging.

AIM

The purpose of this study was to evaluate the efficacy and safety of topical timolol maleate eye drops 0.5% for ETR.

METHODS

In this randomized, single-center, single-blind, placebo-controlled split-face study, 16 patients with mild-to-moderate ETR who presented at West China Hospital between January 2019 to September 2020 were randomized to receive either topical timolol maleate eye drops 0.5% to one side of their face daily for 28 days and normal saline to the other side of the face. Patients were assessed with both the Clinician Erythema Assessment (CEA) and Patient Self-Assessment (PSA) at the 28-day follow-up appointment. Subjective assessment was performed by asking participants to grade their sensation of warmth and burning.

RESULTS

The sides treated with timolol demonstrated a significant improvement in both the CEA and PSA at the 28-day assessment. Patients reported a significant difference in warmth and burning sensations. The only adverse reaction was worsened redness on both sides of the face at Day 1 in one patient.

CONCLUSIONS

In this small study, the application of topical timolol maleate was safe and effective for the treatment of ETR.

Impact of ultraviolet radiation and exposome on rosacea: Key role of photoprotection in optimizing treatment

Background

Pathophysiology of rosacea is not completely understood and involves a complex interaction among genetics, ultraviolet (UV) light, microorganisms, impaired skin barrier, neuronal and vascular dysfunction, and immune system disruption.

Aims

To describe the etiology of rosacea with an emphasis on the role of UV radiation and exposome, and to review the importance of non‐pharmacologic strategies focusing on photoprotection.

Methods

We conducted a narrative review of the literature. We performed literature searches with PubMed from January 1990 to November 2020 using the keywords “rosacea”, “pathogenesis”, “ultraviolet radiation”, “exposome”, “photoprotection”, “sunscreens” and “non‐pharmacologic agents”. The search was limited to English, Spanish, and French language articles.

Results

Several environmental factors such as UV light, diverse microorganisms, air pollution, tobacco smoking, nutrition, and psychological stress showed to trigger or worsen rosacea. UV radiation was reported to induce pro‐inflammatory, pro‐angiogenic, and pro‐fibrotic responses. We found 6 original articles about the impact of sunscreens on rosacea. The use of sunscreens containing ingredients with emollient, anti‐inflammatory, and/or vasoregulatory properties was shown to significantly improve symptomatology.

Conclusion

UV radiation and the exposome play a key role in the development of rosacea. UV light is implicated in all significant aspects of rosacea: skin inflammation, neoangiogenesis, telangiectasia, and fibrosis, and may even initiate rosacea. While the use of sunscreens is widely recommended, the literature on the impact of photoprotection in rosacea is scarce. Adequately formulated sunscreens could not only provide the required level of photoprotection, but may also help to mitigate the barrier dysfunction, neutralize facial redness (tinted sunscreens), and decrease inflammation and vascular dysfunction.

Rosacea is associated with conjoined interactions between physical barrier of the skin and microorganisms: A pilot study

Background

Rosacea is a common condition characterized by transient or persistent central facial erythema, and often papules and pustules. Currently, the role of bacterium in the development and progression of rosacea remains controversial. This study aimed to investigate the difference in the physiological conditions and microorganisms between the lesional and non‐lesional areas of papulopustular rosacea.

Methods

Twenty‐five French patients with papulopustular rosacea were enrolled in this pilot study. Each patient was subjected to clinical assessment, and the skin barrier function was tested in lesional and non‐lesional areas. In addition, samples from the lesional and non‐lesional areas were collected for bacterial culturing.

Results

Of all subjects included in the study, a lower skin conductivity was measured in lesional areas than in non‐lesional areas (43.5 ± 12.4 vs. 57.2 ± 11.6 U, P < .05), and a higher transepidermal water loss (TEWL) value was found in lesional areas than in non‐lesional areas (17.2 ± 5.9 vs. 14.2 ± 4.1 g/(m² h), P < .05). We found a lower TEWL in lesions in rosacea patients with bacterial dysbiosis than in those with bacterial balance (P < .05). In addition, there were significant differences in the skin conductivity and TEWL between lesional and non‐lesional areas in patients with bacterial dysbiosis (P < .001), and no significant differences were seen in patients with bacterial balance (P < .05).

Conclusion

The results of the present study demonstrate that the physiological features of rosacea are closely associated with the interactions between the host and the microorganisms.