Synergistic antimicrobial activity by combining an allylamine with benzoyl peroxide with expanded coverage against yeast and bacterial species

Acne - therapeutic challenges to the cooperation between a dermatologist and a cosmetologist

Acne vulgaris is one of the most common skin diseases in adolescence, causing a significant negative impact on the quality of life of young people who - in a large percentage of cases - do not accept their appearance. The complex pathogenesis of this disease requires appropriate preventive and curative treatment from both a dermatologist and a cosmetologist. The aim of the study was to discuss the methods currently used by dermatologists in local therapy for mild and intermediate forms of acne vulgaris, and to provide an overview of possible preventive and caring activities in the cosmetologist's office. Possible directions of cooperation between the dermatologist and the cosmetologist in the prevention of acne relapse and treatment of possible acne complications were also discussed.

Cysteamine, an Endogenous Aminothiol, and Cystamine, the Disulfide Product of Oxidation, Increase Pseudomonas aeruginosa Sensitivity to Reactive Oxygen and Nitrogen Species and Potentiate Therapeutic Antibiotics against Bacterial Infection

Cysteamine is an endogenous aminothiol produced in mammalian cells as a consequence of coenzyme A metabolism through the activity of the vanin family of pantetheinase ectoenzymes. It is known to have a biological role in oxidative stress, inflammation, and cell migration. There have been several reports demonstrating anti-infective properties targeting viruses, bacteria, and even the malarial parasite. We and others have previously described broad-spectrum antimicrobial and antibiofilm activities of cysteamine. Here, we go further to demonstrate redox-dependent mechanisms of action for the compound and how its antimicrobial effects are, at least in part, due to undermining bacterial defenses against oxidative and nitrosative challenges. We demonstrate the therapeutic potentiation of antibiotic therapy against Pseudomonas aeruginosa in mouse models of infection. We also demonstrate potentiation of many different classes of antibiotics against a selection of priority antibiotic-resistant pathogens, including colistin (often considered an antibiotic of last resort), and we discuss how this endogenous antimicrobial component of innate immunity has a role in infectious disease that is beginning to be explored and is not yet fully understood.

Peroxides with Anthelmintic, Antiprotozoal, Fungicidal and Antiviral Bioactivity: Properties, Synthesis and Reactions

The biological activity of organic peroxides is usually associated with the antimalarial properties of artemisinin and its derivatives. However, the analysis of published data indicates that organic peroxides exhibit a variety of biological activity, which is still being given insufficient attention. In the present review, we deal with natural, semi-synthetic and synthetic peroxides exhibiting anthelmintic, antiprotozoal, fungicidal, antiviral and other activities that have not been described in detail earlier. The review is mainly concerned with the development of methods for the synthesis of biologically active natural peroxides, as well as its isolation from natural sources and the modification of natural peroxides. In addition, much attention is paid to the substantially cheaper biologically active synthetic peroxides. The present review summarizes 217 publications mainly from 2000 onwards.

Characterization of Antimicrobial Agent Loaded Eudragit RS Solvent Exchange-Induced In Situ Forming Gels for Periodontitis Treatment

Eudragit RS (ERS), a quaternary polyacrylate positively charged polymer, exhibits a very low permeability and swells in aqueous media independently of pH without dissolving. Owing to its high solubility in N-methyl pyrrolidone (NMP), it was interesting to apply as polymer matrix for solvent-exchanged in situ forming gel. The aim of this research was to prepare in situ forming gels from ERS to deliver the antimicrobial agents (doxycycline hyclate, metronidazole, and benzoyl peroxide) for periodontitis treatment. They were evaluated for viscosity and rheology, gel formation, syringeability, drug release, and antimicrobial activities. The solvent exchange between NMP and an external aqueous simulated gingival crevicular fluid stimulated the dissolved ERS transforming into the opaque rigid gel. Antimicrobial agent loaded ERS systems exhibited Newtonian flow with acceptable syringeability. The higher-loaded ERS promoted the more prolongation of drug release because of the retardation of water diffusion into the precipitated matrix. Antimicrobial activities against Staphylococcus aureus, Escherichia coli, Candida albicans, Streptococcus mutans, and Porphyromonas gingivalis depended on type of drugs and test microorganisms. Doxycycline hyclate loaded ERS systems showed these activities greater than the others; however, all of them could inhibit all test microorganisms. Thus, the solvent exchange-induced in situ forming gels comprising ERS-antimicrobial drugs exhibited potential use as localized delivery systems for periodontitis treatment.

Activity of Cysteamine against the Cystic Fibrosis Pathogen Burkholderia cepacia Complex

There are no wholly successful chemotherapeutic strategies against Burkholderia cepacia complex (BCC) colonization in cystic fibrosis (CF). We assessed the impact of cysteamine (Lynovex) in combination with standard-of-care CF antibiotics in vitro against BCC CF isolates by the concentration at which 100% of bacteria were killed (MIC₁₀₀) and checkerboard assays under CLSI standard conditions. Cysteamine facilitated the aminoglycoside-, fluoroquinolone- and folate pathway inhibitor-mediated killing of BCC organisms that were otherwise resistant or intermediately sensitive to these antibiotic classes. Slow-growing BCC strains are often recalcitrant to treatment and form biofilms. In assessing the impact of cysteamine on biofilms, we demonstrated inhibition of BCC biofilm formation at sub-MIC₁₀₀s of cysteamine.

Naftifine hydrochloride (NH) in the treatment of pityriasis versicolor

Introduction & objectives: The purpose of this study was to demonstrate the efficacy comparability of 1% NH lotion vs. of 1% NH cream (exoderil, Sandoz) in the treatment of pityriasis versicolor. Material & methods. 71 patients with pityriasis versicolor were randomly allocated either to receive NH lotion once daily (NH lotion group (п = 35, 38.6 years (95% CI [33,7, 43.5]) or NH cream once daily (NH cream group (п = 36, 40.8 years (95% CI [36,6, 45.0]) for 14 days. Mycological evaluations (microscopy and culture) were performed at weeks 2 and 3, inflammation symptoms evaluations were scored at day 3, weeks 2 and 3 after start of the therapy. Overall cure rates assessment included results of mycological, clinical outcomes and safety evaluation. Results. There was no difference between groups in mycological cure rates (94% vs 92%) and inflammation regression (97% vs 97%). Overall cure rate was 91% and 92% of patients in NH lotion and NH cream groups respectively (p = 0,97). Conclusion. 1% NH lotion and 1% NH cream are effective in the treatment of pityriasis versicolor.

Naftifine hydrochloride in treatment of foot mycosis complicated with a bacterial infection and significant inflammatory reaction

Goal of the study. To compare the etticacy ot nattitine hydrochloride (Exoderil® cream) and combination cream comprising betamethasone dipropionate, clotrimazole and gentamicin sultate in treatment ot toot mycosis complicated with a bacterial intection and signiticant intlammatory reaction. Materials and methods. A single-center, prospective, randomized, open-label comparative study involved 75 patients aged 23-80 suttering trom toot mycosis complicated with a bacterial intection and signiticant intlammatory reaction. The patients were randomized in two groups. The tirst group comprised 36 patients receiving nattitine hydrochloride while the second one included 39 patients treated with a combination drug comprising betamethasone, clotrimazole and gentamicin. Results. The anti-bacterial etticacy ot nattitine and combination drug comprising betamethasone, clotrimazole and gentamicin was comparable. Complete sanitation ot the bacterial intection was achieved in 94% ot the patients in both groups. The antimycotic etticacy ot nattitine (Exoderil® cream) was reliably higher than that ot the three-component drug to amount to 97% and 82%, respectively (p = 0.03). Complete recovery was achieved in 92% ot the patients treated with nattitine hydrochloride cream and 82% ot the patients treated with the three-component drug (p = 0.22). Conclusion. Exoderil® cream (active substance: nattitine) is a highly etticient drug tor treatment ot ditterent clinical torms ot skin mycosis including those accompanied by a signiticant intlammatory reaction and/or concomitant bacterial intection.

Cysteamine (Lynovex®), a novel mucoactive antimicrobial & antibiofilm agent for the treatment of cystic fibrosis

Background

There remains a critical need for more effective, safe, long-term treatments for cystic fibrosis (CF). Any successful therapeutic strategy designed to combat the respiratory pathology of this condition must address the altered lung physiology and recurrent, complex, polymicrobial infections and biofilms that affect the CF pulmonary tract. Cysteamine is a potential solution to these unmet medical needs and is described here for the first time as (Lynovex®) a single therapy with the potential to deliver mucoactive, antibiofilm and antibacterial properties; both in oral and inhaled delivery modes. Cysteamine is already established in clinical practice for an unrelated orphan condition, cystinosis, and is therefore being repurposed (in oral form) for cystic fibrosis from a platform of over twenty years of safety data and clinical experience.

Methods

The antibacterial and antibiofilm attributes of cysteamine were determined against type strain and clinical isolates of CF relevant pathogens using CLSI standard and adapted microbiological methods and a BioFlux microfluidic system. Assays were performed in standard nutrient media conditions, minimal media, to mimic the low metabolic activity of microbes/persister cells in the CF respiratory tract and in artificial sputum medium. In vivo antibacterial activity was determined in acute murine lung infection/cysteamine nebulisation models. The mucolytic potential of cysteamine was assessed against DNA and mucin in vitro by semi-quantitative macro-rheology. In all cases, the ‘gold standard’ therapeutic agents were employed as control/comparator compounds against which the efficacy of cysteamine was compared.

Results

Cysteamine demonstrated at least comparable mucolytic activity to currently available mucoactive agents. Cysteamine was rapidly bactericidal against both metabolically active and persister cells of Pseudomonas aeruginosa and also emerging CF pathogens; its activity was not sensitive to high ionic concentrations characteristic of the CF lung. Cysteamine prevented the formation of, and disrupted established P. aeruginosa biofilms. Cysteamine was synergistic with conventional CF antibiotics; reversing antibiotic resistance/insensitivity in CF bacterial pathogens.

Conclusions

The novel mucolytic-antimicrobial activity of cysteamine (Lynovex®) provides potential for a much needed new therapeutic strategy in cystic fibrosis. The data we present here provides a platform for cysteamine’s continued investigation as a novel treatment for this poorly served orphan disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s13023-014-0189-2) contains supplementary material, which is available to authorized users.

Co-operative inhibitory effects of hydrogen peroxide and iodine against bacterial and yeast species

BACKGROUND

Hydrogen peroxide and iodine are powerful antimicrobials widely used as antiseptics and disinfectants. Their antimicrobial properties are known to be enhanced by combining them with other compounds. We studied co-operative inhibitory activities (synergism, additive effects and modes of growth inhibition) of hydrogen peroxide and iodine used concurrently against 3 bacterial and 16 yeast species.

RESULTS

Synergistic or additive inhibitory effects were shown for hydrogen peroxide and iodine mixtures against all 19 species used in the study. Both biocides were mostly cidal individually and in mixtures against Pseudomonas aeruginosa and Staphylococcus aureus. Both compounds manifested static inhibitory effects individually, but their mixtures were synergistically cidal for Saccharomyces cerevisiae and Escherihia coli. Cells of S. cerevisiae treated with hydrogen peroxide and iodine-hydrogen peroxide mixture produced increased numbers of respiratory deficient mutants indicating genotoxic effects.

CONCLUSION

Iodine and hydrogen peroxide used concurrently interact synergistically or additively against a range of prokaryotic and eukaryotic microorganisms. The study provides an insight as to how these traditional antimicrobials could be used more effectively for disinfection and antisepsis. In addition, a simple approach is proposed for scoring genotoxicity of different biocides by using the budding yeast system.

Emerging drugs for acne

Acne vulgaris is a common skin disorder that affects most individuals at some point in their lives. It may result in significant morbidity, including cutaneous scarring and psychological impairment. Current treatments include topical retinoids, benzoyl peroxide, topical and systemic antibiotics, and systemic isotretinoin. There are growing concerns of rising antibiotic resistance, significant side effects of isotretinoin therapy, and lack of safe and effective treatment for pregnant females. Recent advances in the pathogenesis of acne have led to a greater understanding of the underlying inflammatory mechanisms and the role the Propionibacterium acnes and biofilms. This has led to the development of new therapeutic targets. This article reviews emerging treatments of acne, including topical picolinic acid, topical antibiotic dapsone, systemic zinc salts, oral antibiotic lymecycline, new formulations of and synergistic combinations of benzoyl peroxide, photodynamic therapy with topical photosensitizers and potential acne vaccines.

Treatment of acne vulgaris without antibiotics: tertiary amine?benzoyl peroxide combination vs. benzoyl peroxide alone (Proactiv Solution?)

BACKGROUND

Concerns have arisen over the development of antibiotic-resistant organisms due to the prolonged use of oral and topical antibiotics in acne vulgaris. We have previously demonstrated that benzoyl peroxide used in consort with a chemical with an accessible tertiary amine, such as an allylamine, increases radical activity and biological effect.

OBJECTIVES

The purpose of this pilot study was to assess the efficacy of two nonantibiotic topical remedies for mild to moderate acne, with one of the agents being a combination of benzoyl peroxide with butenifine, an allylamine.

METHODS

In an open-label, patient-satisfaction, 8-week comparative study, 23 patients demonstrating mild to moderate facial acne were given randomly either benzoyl peroxide in Proactiv Solution or the combination of benzoyl peroxide with an allylamine.

RESULTS

The allylamine-benzoyl peroxide combination therapy outperformed Proactiv Solution during each 2-week stage of evaluation in terms of reduction of comedones, inflammatory lesions, and degree of oiliness. There was a marked preference for the allylamine-benzoyl peroxide combination in terms of patient satisfaction.

CONCLUSIONS

Benzoyl peroxide used in consort with antimicrobial agents that contain an accessible tertiary amine, such as erythromycin, has previously been shown to increase radical activity and biological effect. Trials of short duration with small numbers of patients do not adequately inform practitioners about whether the combination of allylamines with benzoyl peroxide is a viable alternative to topical antibiotic therapy for acne. Nevertheless, the higher satisfaction with the allylamine-benzoyl peroxide combination certainly warrants further investigation.