Oxymetazoline inhibits and resolves inflammatory reactions in human neutrophils

Emerging Medical Therapies in Rosacea: A Narrative Review

Rosacea is a chronic inflammatory disease with a multifactorial pathogenesis. The wide spectrum of clinical phenotypes, including erythema, telangiectasia, inflammatory papules and pustules, and phyma, demand an individualized approach to treatment. This narrative review offers an updated reference for rosacea management by covering the latest developments in both topical and systemic treatments, including data from newly approved therapies, updates to current treatment modalities and ongoing clinical trials. Although use of benzoyl peroxide as a treatment for rosacea has typically been limited due to irritation, the improved tolerability due to microencapsulation of benzoyl peroxide 5% cream provides a new therapeutic option for patients with rosacea. Minocycline foam and topical ivermectin cream add to our armamentarium of treatment options, particularly for inflammatory papules and pustules. Sarecycline has a narrower spectrum of antibacterial activity, which might reduce the development of antibiotic resistance and disruption of the microbiome compared to other oral antibiotics. Brimonidine gel and oxymetazoline cream provide topical options for redness and flushing. There is emerging evidence about the role of hydroxychloroquine and intradermal botulinum toxin A, which may improve rosacea through their effects on mast cells. The clinical trials pipeline includes agents with a variety of mechanisms, including mast cell stabilization, antimicrobial, anti-inflammatory, and vasoconstrictive effects. However, the clinical pipeline for rosacea appears limited, and there remain important unmet needs for patients with more recalcitrant rosacea or phymatous disease. In addition, there is a need for comparative effectiveness studies to identify the highest value treatment approaches for patients with rosacea.

The role of the topical nasal decongestant oxymetazoline as a novel therapeutic option for post-acne erythema: A split-face, double-blind, randomized, placebo-controlled trial

Post-acne erythema (PAE) is one of the most common sequelae of acne inflammation. Unfortunately, the treatment of PAE remains challenging due to limited effective topical treatments. The objectives of this study were to evaluate the efficacy and safety of topical oxymetazoline hydrochloride (OxH) 0.05% solution for PAE. This study was a split-face, participants-and investigators-blinded, randomized, placebo-controlled trial conducted between December 2021 and March 2022 in Bangkok, Thailand. Healthy adults aged from 18 to 45 years with mild to severe PAE, according to the Clinician's Erythema Assessment (CEA), on both sides of the face were eligible. After randomization, each participant applied the OxH to one side of their face and a placebo to the contralateral face twice daily for 12 weeks. The primary outcome was PAE lesion counts. The secondary outcomes were erythema index, clinical response rate at week 12 ("clear," "almost clear," or "at least two-grade improvement" by CEA), and patient satisfaction scores. A total of 30 participants were enrolled. The OxH-treated skin showed a significantly greater mean difference (MD) reduction in PAE lesion counts than the placebo after 8 weeks of treatment (4.30, 95% confidence interval [CI] 1.42-7.18). Similarly, the MD reduction of the erythema index was higher in the OxH-treated skin from the second week (11.82, 95% CI 8.48-15.15). Additionally, the OxH-treated side also achieved a higher clinical response rate after 8 weeks of treatment (40.00% vs. 6.67%; p = 0.002) and rated higher satisfaction than those using the placebo at the end of the study (mean [standard deviation] satisfaction score 8.30 [0.18] vs 7.40 [0.18], P < 0.001). There were no serious adverse events or flares of erythema during the study. In conclusion, our study demonstrated that the topical OxH 0.05% solution was effective, well-tolerated, and safe for reducing PAE without a rebound effect. It could be a choice of PAE management. Trial Registration: Thai Clinical Trials Registry No. TCTR20211207004.

Benefits and safety of Oxymetazoline cream 1% on rosacea-associated erythema: A systematic review and analysis of clinical evidence

BACKGROUND

Facial persistent erythema is recognized as difficult feature to treat in rosacea. Topical Oxymetazoline cream 1% has been used to treat persistent facial erythema in rosacea patients for some years.

OBJECTIVE

To quantitatively synthesize the benefits and harms of Oxymetazoline cream 1% in real-world clinical management of treatment response and adverse events.

METHODS

The clinical researches before June 1, 2022 published on online databases including PubMed, Web of Science, Embase and Cochrane Library were meta-analyzed.

RESULTS

A total of 2298 participants were included, and the improvement rate of two-grade Clinician Erythema Assessment score (CEA) and Subject Self-Assessment for rosacea facial redness score (SSA) in Oxymetazoline group was 38% (95%CI 28-48) and 25% (95%CI 22-27), respectively, at the 4th week of the dosing. The comprehensive rate of treatment-related TEAEs in Oxymetazoline group was 7% (95%CI 5-8). The rate of stinging/burning was 15% (95%CI 10-19), pruritus was 15% (95%CI 9-22), dryness was 23% (95%CI 18-28), and scaling was 17% (95%CI 12-22) in analysis of dermal tolerability. And topical Oxymetazoline cream 1.0% presented a very low rebound rate of erythema (1%, 95%CI 0-2).

CONCLUSIONS

These real-world data on Oxymetazoline cream 1% in rosacea-associated erythema may help making clinic decision and informing treatment expectations, and more clinic trials on longer-term dosing or the combination treatment with oral medication and energy-based therapy are worth exploring.

Untangling the web of 5-lipoxygenase-derived products from a molecular and structural perspective: The battle between pro- and anti-inflammatory lipid mediators

Arachidonic acid (AA) is the precursor to leukotrienes (LT), potent mediators of the inflammatory response. In the 35 + years since cysteinyl-LTs were reported to mediate antigen-induced constriction of bronchi in tissue from asthma patients, numerous cellular responses evoked by the LTs, such as chemoattraction and G protein-coupled receptor (GPCR) activation, have been elucidated and revealed a potential for 5-lipoxygenase (5-LOX) as a promising drug target that goes beyond asthma. We describe herein early work identifying 5-LOX as the key enzyme that initiates LT biosynthesis and the discovery of its membrane-embedded helper protein required to execute the two-step reaction that transforms AA to the progenitor leukotriene A4 (LTA4). 5-LOX must traffic to the nuclear membrane to interact with its partner and undergo a conformational change so that AA can enter the active site. Additionally, the enzyme must retain the hydroperoxy-reaction intermediate for its final transformation to LTA4. Each of these steps provide a unique target for inhibition. Next, we describe the recent structures of GPCRs that recognize metabolites of the 5-LOX pathway and thus provide target alternatives. We also highlight the role of 5-LOX in the biosynthesis of anti-inflammatory lipid mediators (LM), the so-called specialized pro-resolving mediators (SPM). The involvement of 5-LOX in the biosynthesis of LM with opposing functions undoubtedly complicates the continuing search for 5-LOX inhibitors as therapeutic leads. Finally, we address the recent discovery of how some allosteric 5-LOX inhibitors promote oxygenation at the 12/15 carbon on AA to generate mediators that resolve, rather than promote, inflammation.

From Vietnamese plants to a biflavonoid that relieves inflammation by triggering the lipid mediator class switch to resolution

Chronic inflammation results from excessive pro-inflammatory signaling and the failure to resolve the inflammatory reaction. Lipid mediators orchestrate both the initiation and resolution of inflammation. Switching from pro-inflammatory to pro-resolving lipid mediator biosynthesis is considered as efficient strategy to relieve chronic inflammation, though drug candidates exhibiting such features are unknown. Starting from a library of Vietnamese medical plant extracts, we identified isomers of the biflavanoid 8-methylsocotrin-4'-ol from Dracaena cambodiana, which limit inflammation by targeting 5-lipoxygenase and switching the lipid mediator profile from leukotrienes to specialized pro-resolving mediators (SPM). Elucidation of the absolute configurations of 8-methylsocotrin-4'-ol revealed the 2S,γS-isomer being most active, and molecular docking studies suggest that the compound binds to an allosteric site between the 5-lipoxygenase subdomains. We identified additional subordinate targets within lipid mediator biosynthesis, including microsomal prostaglandin E2 synthase-1. Leukotriene production is efficiently suppressed in activated human neutrophils, macrophages, and blood, while the induction of SPM biosynthesis is restricted to M2 macrophages. The shift from leukotrienes to SPM was also evident in mouse peritonitis in vivo and accompanied by a substantial decrease in immune cell infiltration. In summary, we disclose a promising drug candidate that combines potent 5-lipoxygenase inhibition with the favorable reprogramming of lipid mediator profiles.

Topical Oxymetazoline Hydrochloride Cream 1% for the Treatment of Persistent Facial Erythema of Rosacea in Adults: A Comprehensive Review of Current Evidence

BACKGROUND: Rosacea is a chronic, multisymptom, inflammatory condition that affects the centrofacial skin. Facial erythema associated with rosacea can negatively impact a patient's quality of life and is often hard to treat. OBJECTIVE: We sought to review the literature on the role of alpha-adrenergic receptors (α-adrenoceptors) in the context of persistent facial erythema in patients with rosacea and the use of oxymetazoline hydrochloride cream 1% as a topical treatment. METHODS: PubMed was searched; search terms included "alpha adrenoceptor," "oxymetazoline," and "rosacea." Additional articles were identified from the reference lists of the results. RESULTS: Some α-adrenoceptor agonists have vasoconstrictive properties and may be used topically to treat persistent facial erythema in rosacea. Oxymetazoline hydrochloride cream 1% is an α_1A-adrenoceptor agonist approved for the treatment of persistent facial erythema associated with rosacea. Based on our review, we discuss the role of the α-adrenoceptor in persistent facial erythema; provide an overview of the mechanism of action of α-adrenoceptor agonists, such as oxymetazoline, in the treatment of persistent facial erythema; and summarize the clinical development and data to date demonstrating the efficacy and safety of oxymetazoline in the treatment of persistent facial erythema associated with rosacea. CONCLUSION: The review of available literature suggests that oxymetazoline cream is well-tolerated, safe, and effective for the treatment of persistent facial erythema in rosacea and is an important component of combination treatment regimens, which are likely to become the standard of treatment for rosacea in the future.

Comparative transcriptome analysis of SARS-CoV, MERS-CoV, and SARS-CoV-2 to identify potential pathways for drug repurposing

The ongoing COVID-19 pandemic caused by the coronavirus, SARS-CoV-2, has already caused in excess of 1.25 million deaths worldwide, and the number is increasing. Knowledge of the host transcriptional response against this virus and how the pathways are activated or suppressed compared to other human coronaviruses (SARS-CoV, MERS-CoV) that caused outbreaks previously can help in the identification of potential drugs for the treatment of COVID-19. Hence, we used time point meta-analysis to investigate available SARS-CoV and MERS-CoV in-vitro transcriptome datasets in order to identify the significant genes and pathways that are dysregulated at each time point. The subsequent over-representation analysis (ORA) revealed that several pathways are significantly dysregulated at each time point after both SARS-CoV and MERS-CoV infection. We also performed gene set enrichment analyses of SARS-CoV and MERS-CoV with that of SARS-CoV-2 at the same time point and cell line, the results of which revealed that common pathways are activated and suppressed in all three coronaviruses. Furthermore, an analysis of an in-vivo transcriptomic dataset of COVID-19 patients showed that similar pathways are enriched to those identified in the earlier analyses. Based on these findings, a drug repurposing analysis was performed to identify potential drug candidates for combating COVID-19.

Changes of tear lipid mediators after eyelid warming or thermopulsation treatment for meibomian gland dysfunction

Meibomian gland dysfunction (MGD) represents a major cause of dry eye and ocular discomfort. Lipid mediators, often termed oxylipins, can be produced enzymatically or non-enzymatically, and may modulate inflammatory processes in MGD. Here, we aimed to assess the longitudinal changes of lipid mediators after various eyelid treatments (eyelid warming and thermopulsation) over 12 weeks. Secondly, we aimed to assess the chirality of mono-hydroxyl lipid mediators from tears of MGD and healthy participants. Tears lipid mediators were extracted from Schirmer's strips and levels were quantified by liquid chromatography mass spectrometry (LC-MS) techniques. We quantified 33 lipid mediators in the tear, 18 of which (including 11-HETE, 20-OH-LTB4, and 15-oxoETE) were reduced significantly after treatment. Changes in concentrations of 10-HDoHE (r = 0.54) and 15-oxoETE (r = 0.54) were correlated to the number of meibomian gland plugs at baseline, so increased severity of MGD was associated with treatment-induced change in lipid mediators. The chiral analysis demonstrated that 5(S)-HETE, 12(S)-HETE, 15(S)-HETE, 14(S)-HDoHE, 17(S)-HDoHE and 11(R)-HETE were produced with significant enantiomeric excess (ee %) in controls compared to patients, due to enantiomer selective enzymatic action, whereas most lipid mediators were racemates in patients, due to dominance of oxidative effects which have no enantiomeric preference. Treatment of MGD restored the concentrations of 15(S)-HETE, 14(S)-HDoHE and 17(S)-HDoHE with significant ee values, suggesting reduction in oxidative action. Overall, MGD therapy reduced pro-inflammatory molecules generated by lipoxygenase and oxidative stress.

Acute allergic rhinitis

Allergic rhinitis is a common and troubling condition. Basic management of this condition has been well described. However, acute exacerbations of the chronic condition allergic rhinitis are a seldom discussed or described problem despite the fact that even well-controlled patients frequently have exacerbations. This consideration means that a new approach is necessary to define the management of these patients. There are three important events that illustrate the need for a new therapeutic approach:A person who gets a new diagnosis of allergic rhinitis, but has symptoms for many months or yearsA sufferer of allergic rhinitis who is exposed to an environment that triggers an exacerbationA person who has an exacerbation related to another trigger.Recognition of triggers and management strategies to correctly use 'relief' therapies such as topical nasal decongestants is the key to successful management. In addition, the use of an 'action plan', as for asthma, is useful.

Treating acute rhinitis and exacerbations of chronic rhinitis - A role for topical decongestants?

Acute nasal symptoms are troublesome for patients. In addition, these symptoms are encountered frequently by individuals because of common infectious diseases, especially rhinovirus, giving rise to a ‘common cold’. Acute nasal symptoms include rhinorrhoea, sneezing, nasal itch and congestion. Of these, nasal congestion is the most irritating. Because topical nasal decongestants provide rapid and dramatic relief from these symptoms, especially nasal congestion, they are frequently used and abused by patients. Guidance for indications, choice of most efficacious decongestant and recommendations for limiting side effects are thus essential to be imparted to patients by doctors.

Analysis of HETEs in human whole blood by chiral UHPLC-ECAPCI/HRMS

The biosynthesis of eicosanoids occurs enzymatically via lipoxygenases, cyclooxygenases, and cytochrome P450, or through nonenzymatic free radical reactions. The enzymatic routes are highly enantiospecific. Chiral separation and high-sensitivity detection methods are required to differentiate and quantify enantioselective HETEs in complex biological fluids. We report here a targeted chiral lipidomics analysis of human blood using ultra-HPLC-electron capture (EC) atmospheric pressure chemical ionization/high-resolution MS. Monitoring the high-resolution ions formed by the fragmentation of pentafluorobenzyl derivatives of oxidized lipids during the dissociative EC, followed by in-trap fragmentation, increased sensitivity by an order of magnitude when compared with the unit resolution MS. The 12(S)-HETE, 12(S)-hydroxy-(5Z,8E,10E)-heptadecatrienoic acid [12(S)-HHT], and 15(S)-HETE were the major hydroxylated nonesterified chiral lipids in serum. Stimulation of whole blood with zymosan and lipopolysaccharide (LPS) resulted in stimulus- and time-dependent effects. An acute exposure to zymosan induced ∼80% of the chiral plasma lipids, including 12(S)-HHT, 5(S)-HETE, 15(R)-HETE, and 15(S)-HETE, while a maximum response to LPS was achieved after a long-term stimulation. The reported method allows for a rapid quantification with high sensitivity and specificity of enantiospecific responses to in vitro stimulation or coagulation of human blood.

Does oxymetazoline increase the efficacy of nasal steroids in treating nasal polyposis?

BACKGROUND

Although nasal steroids are the mainstay treatments in nasal polyposis, up to one-half of patients do not respond and need surgical treatment. This study aimed to evaluate whether oxymetazoline administration produces any additive effect on nasal steroid therapy and whether rebound congestion develops after oxymetazoline treatment.

METHODS

Sixty-eight patients with nasal polyposis were randomly assigned in a 1:1 ratio to receive either oxymetazoline plus mometasone furoate nasal spray (MFNS) or placebo plus MFNS, 2 sprays per nostril twice daily, with an interval of 5 minutes between each medication for 4 weeks. All the patients were then treated with MFNS, 2 sprays per nostril twice daily for 2 weeks. The nasal symptoms score, peak inspiratory flow index, nasal mucociliary clearance time (NMCCT), and total nasal polyps score were used to evaluate treatment outcomes. An intention-to-treat analysis was performed, and a worst case sensitivity analysis was applied to missing cases.

RESULTS

Thirty-four patients were allocated to the oxymetazoline-MFNS group, and 34 to the placebo-MFNS group. One patient in each group was lost to last-visit follow-up. At 4 weeks after beginning treatment, the oxymetazoline-MFNS group showed significantly greater improvement in blocked nose, hyposmia, peak flow, NMCCT, and total nasal polyps score than the placebo-MFNS group. During the nasal steroid phase, both groups showed continuing improvement in all outcome variables. However, the oxymetazoline-MFNS group still showed significantly greater improvement in blocked nose, hyposmia, NMCCT, and total nasal polyps score, but not peak flow, than the placebo-MFNS group at the end of the study.

CONCLUSION

The use of nasal steroids with oxymetazoline was more effective over 6 weeks than nasal steroids alone in improving blocked nose, hyposmia, nasal mucociliary clearance, and polyp size in treatment of nasal polyposis. There was no evidence of rebound congestion after 4 weeks of oxymetazoline treatment.

Ultrafine particles affect the balance of endogenous pro- and anti-inflammatory lipid mediators in the lung: in-vitro and in-vivo studies

Background

Exposure to ultrafine particles exerts diverse harmful effects including aggravation of pulmonary diseases like asthma. Recently we demonstrated in a mouse model for allergic airway inflammation that particle-derived oxidative stress plays a crucial role during augmentation of allergen-induced lung inflammation by ultrafine carbon particle (UfCP) inhalation. The mechanisms how particle inhalation might change the inflammatory balance in the lungs, leading to accelerated inflammatory reactions, remain unclear. Lipid mediators, known to be immediately generated in response to tissue injury, might be strong candidates for priming this particle-triggered change of the inflammatory balance.

Methods

We hypothesize that inhalation of UfCP may disturb the balance of pro- and anti-inflammatory lipid mediators in: i) a model for acute allergic pulmonary inflammation, exposing mice for 24 h before allergen challenge to UfCP inhalation (51.7 nm, 507 μg/m³), and ii) an in-vitro model with primary rat alveolar macrophages (AM) incubated with UfCP (10 μg/1 x 10⁶ cells/ml) for 1 h. Lungs and AM were analysed for pro- and anti-inflammatory lipid mediators, namely leukotriene B₄ (LTB₄), prostaglandin E₂ (PGE₂), 15(S)-hydroxy-eicosatetraenoic acid (15(S)-HETE), lipoxin A₄ (LXA₄) and oxidative stress marker 8-isoprostane by enzyme immunoassays and immunohistochemistry.

Results

In non-sensitized mice UfCP exposure induced a light non-significant increase of all lipid mediators. Similarly but significantly in rat AM all lipid mediators were induced already within 1 h of UfCP stimulation. Also sensitized and challenge mice exposed to filtered air showed a partially significant increase in all lipid mediators. In sensitized and challenged mice UfCP exposure induced highest significant levels of all lipid mediators in the lungs together with the peak of allergic airway inflammation on day 7 after UfCP inhalation. The levels of LTB₄, 8-isoprostane and PGE₂ were significantly increased also one day after UfCP exposure. Immunohistochemistry localized highest concentrations of PGE₂ especially in AM one day after UfCP exposure.

Conclusion

Our results suggest that UfCP exposure affects the balance between pro- and anti-inflammatory lipid mediators. In allergic mice, where the endogenous balance of pro- and anti-inflammatory mediators is already altered, UfCP exposure aggravates the inflammation and the increase in anti-inflammatory, pro-resolving lipid mediators is insufficient to counterbalance the extensive inflammatory response. This may be a contributing mechanism that explains the increased susceptibility of asthmatic patients towards particle exposure.