Epidemiologic Study of Malassezia Yeasts in Acne Patients by Analysis of 26S rDNA PCR-RFLP

A review of skin immune processes in acne

Acne vulgaris is one of the most prevalent skin conditions, affecting almost all teenagers worldwide. Multiple factors, including the excessive production of sebum, dysbiosis of the skin microbiome, disruption of keratinization within hair follicles, and local inflammation, are believed to trigger or aggravate acne. Immune activity plays a crucial role in the pathogenesis of acne. Recent research has improved our understanding of the immunostimulatory functions of microorganisms, lipid mediators, and neuropeptides. Additionally, significant advances have been made in elucidating the intricate mechanisms through which cutaneous innate and adaptive immune cells perceive and transmit stimulatory signals and initiate immune responses. However, our understanding of precise temporal and spatial patterns of immune activity throughout various stages of acne development remains limited. This review provides a comprehensive overview of the current knowledge concerning the immune processes involved in the initiation and progression of acne. Furthermore, we highlight the significance of detailed spatiotemporal analyses, including analyses of temporal dynamics of immune cell populations as well as single-cell and spatial RNA sequencing, for the development of targeted therapeutic and prevention strategies.

Part 1: Understanding the role of Malassezia spp. in skin disorders: Malassezia yeasts as commensal or pathogenic organisms of human and animal skin

INTRODUCTION

Malassezia spp. are a group of lipid-dependent basidiomycetes yeasts acting as commensal organisms of the human and animal skin. However, under some not well-defined circumstances, these yeasts may switch to opportunistic pathogens triggering a number of skin disorders with different clinical presentations. The genus comprises of 18 lipid-dependent species with a variable distribution in the hosts and pathologies thus suggesting a host- and microbe-specific interactions.

AREA COVERED

This review highlighted and discussed the most recent literature regarding the genus Malassezia as a commensal or pathogenic organisms highlighting Malassezia-associated skin disorders in humans and animals and their antifungal susceptibility profile. A literature search of Malassezia associated skin disorders was performed via PubMed and Google scholar (up to May 2023), using the different keywords mainly associated with Malassezia skin disorders and Malassezia antifungal resistance.

EXPERT OPINION

Malassezia yeasts are part of the skin mycobiota and their life cycle is strictly associated with the environment in which they live. The biochemical, physiological, or immunological condition of the host skin selects Malassezia spp. or genotypes able to survive in a specific environment by changing their metabolisms, thus producing virulence factors or metabolites which can cause skin disorders with different clinical presentations.

Particulate matter increases Cutibacterium acnes-induced inflammation in human epidermal keratinocytes via the TLR4/NF-κB pathway

Recent studies have demonstrated that particulate matter (PM) can induce oxidative stress and inflammatory responses that are related to the development or exacerbation of several inflammatory dermatoses. However, the effect of PM on acne vulgaris has yet to be determined. In this study, we induced acne-like inflammation in HEKn cells with several concentrations of Cutibacterium acnes (C. acnes) and Staphylococcus aureus peptidoglycan (PGN) to investigate whether PM exposure exacerbates acne-like inflammation and elucidate the underlying mechanisms. To confirm whether PM increases the messenger ribonucleic acid (mRNA) and protein levels of proinflammatory cytokines (IL-1α, IL-1β, IL-6, IL-8, and TNF-α) and cyclooxygenase (COX)-2 expression in C. acnes- or PGN-treated HEKn cells, we used quantitative real-time polymerase chain reactions, enzyme-linked immunosorbent assays, and western blot assays. The results demonstrated that C. acnes, PGN, and PM induced the expression of proinflammatory cytokines in a time- and dose-dependent manner at the mRNA and protein levels, respectively. Moreover, PM further increased the expression of proinflammatory cytokines, COX2, TLR4, and the phosphorylation of NF-κB in C. acnes- and PGN-treated HEKn cells. In conclusion, our results suggest that PM may exacerbate acne symptoms by increasing the inflammatory response.

Molecular epidemiology, in vitro susceptibility and exoenzyme screening of Malassezia clinical isolates

Introduction. Malassezia folliculitis (MF) and pityriasis versicolor (PV) are common dermatoses caused by Malassezia species. Their molecular epidemiology, drug susceptibility and exoenzymes are rarely reported in China.Aim. To investigate the molecular epidemiology, drug susceptibility and enzymatic profile of Malassezia clinical isolates.Methodology. Malassezia strains were recovered from MF and PV patients and healthy subjects (HS) and identified by sequencing analysis. The minimum inhibitory concentrations (MICs) of nine antifungals (posaconazole, voriconazole, itraconazole, fluconazole, ketoconazole, miconazole, bifonazole, terbinafine and caspofungin) and tacrolimus, the interactions between three antifungals (itraconazole, ketoconazole and terbinafine) and tacrolimus, and the extracellular enzyme profile were evaluated using broth and checkerboard microdilution and the Api-Zym system, respectively.Results. Among 392 Malassezia isolates from 729 subjects (289 MF, 218 PV and 222 HS), Malassezia furfur and Malassezia globosa accounted for 67.86 and 18.88 %, respectively. M. furfur was the major species in MF and PV patients and HS. Among 60M. furfur and 50M. globosa strains, the MICs for itraconazole, posaconazole, voriconazole and ketoconazole were <1 μg ml^-1. M. furfur was more susceptible to itraconazole, terbinafine and bifonazole but tolerant to miconazole compared with M. globosa (P<0.05). Synergistic effects between terbinafine and itraconazole or between tacrolimus and itraconazole, ketoconazole or terbinafine occurred in 6, 7, 6 and 9 out of 37 strains, respectively. Phosphatases, lipases and proteases were mainly secreted in 51 isolates.Conclusions. Itraconazole, posaconazole, voriconazole and ketoconazole are theagents against which there is greatest susceptibility. Synergistic effects between terbinafine and itraconazole or tacrolimas and antifungals may be irrelevant to clinical application. Overproduction of lipases could enhance the skin inhabitation of M. furfur.

Potential Role of the Microbiome in Acne: A Comprehensive Review

Acne is a highly prevalent inflammatory skin condition involving sebaceous sties. Although it clearly develops from an interplay of multiple factors, the exact cause of acne remains elusive. It is increasingly believed that the interaction between skin microbes and host immunity plays an important role in this disease, with perturbed microbial composition and activity found in acne patients. Cutibacterium acnes (C. acnes; formerly called Propionibacterium acnes) is commonly found in sebum-rich areas and its over-proliferation has long been thought to contribute to the disease. However, information provided by advanced metagenomic sequencing has indicated that the cutaneous microbiota in acne patients and acne-free individuals differ at the virulent-specific lineage level. Acne also has close connections with the gastrointestinal tract, and many argue that the gut microbiota could be involved in the pathogenic process of acne. The emotions of stress (e.g., depression and anxiety), for instance, have been hypothesized to aggravate acne by altering the gut microbiota and increasing intestinal permeability, potentially contributing to skin inflammation. Over the years, an expanding body of research has highlighted the presence of a gut–brain–skin axis that connects gut microbes, oral probiotics, and diet, currently an area of intense scrutiny, to acne severity. This review concentrates on the skin and gut microbes in acne, the role that the gut–brain–skin axis plays in the immunobiology of acne, and newly emerging microbiome-based therapies that can be applied to treat acne.

Acne, the Skin Microbiome, and Antibiotic Treatment

Acne vulgaris is a chronic skin disorder involving hair follicles and sebaceous glands. Multiple factors contribute to the disease, including skin microbes. The skin microbiome in the follicle is composed of a diverse group of microorganisms. Among them, Propionibacterium acnes and Malassezia spp. have been linked to acne development through their influence on sebum secretion, comedone formation, and inflammatory response. Antibiotics targeting P. acnes have been the mainstay in acne treatment for the past four decades. Among them, macrolides, clindamycin, and tetracyclines are the most widely prescribed. As antibiotic resistance becomes an increasing concern in clinical practice, understanding the skin microbiome associated with acne and the effects of antibiotic use on the skin commensals is highly relevant and critical to clinicians. In this review, we summarize recent studies of the composition and dynamics of the skin microbiome in acne and the effects of antibiotic treatment on skin microbes.

Pathogenic Yeasts Recovered From Acne Vulgaris: Molecular Characterization and Antifungal Susceptibility Pattern

Context:

Acne vulgaris is a disorder showing persistent inflammation in the pilosebaceous follicles. It is one of the most prevalent dermatoses that millions of people suffer from globally.

Aim:

The aim of this study was to identify Candida species from patients with acne and to determine their drugs susceptibility.

Subjects and Methods:

A total of 70 cutaneous samples from acne vulgaris patients suspected to have Candida infections were collected. Macroscopic and microscopic morphology were recorded followed by polymerase chain reaction-sequencing of ITS regions, using universal primers. In vitro antifungal susceptibility was performed using Clinical and Laboratory Standards Institute method.

Results:

Overall, 11 Candida species including Candida parapsilosis 8 (72.73%), Candida krusei 1 (12.5%), Candida lusitaniae 1 (12.5%), Candida kefyr 1 (12.5%), and a Trichosporon asahi out of the collected clinical materials were isolated and identified. C. parapsilosis isolates susceptibility to diverse concentrations of the antifungal agents to isolate Cp1 study indicated that the isolated Cp8 and Cp5 with minimal inhibitory concentration (MIC) 50 = 32, 0.5, 0.25 and MIC 90 of <64, <1, <0.5 μg/ml fluconazole, itraconazole, and ketoconazole were resistant, respectively. Some of the isolates having relative strength, almost all other species of C. parapsilosis isolates were susceptible to these drugs.

Conclusion:

C. parapsilosis was the most prevalent Candida species in acne vulgaris samples which had higher in vitro susceptibility for antifungals.

An approach on the potential use of probiotics in the treatment of skin conditions: acne and atopic dermatitis

Acne and Atopic Dermatitis (AD) are chronic inflammatory skin conditions with severe impact on a patient's life. Current treatments are related to adverse effects and do not represent a definitive cure. The present paper reviews the alterations in skin microbiome, specifically in acne and AD, and aims in searching for potential treatments based on benefic microorganisms, called probiotics. The review was made through bibliographic search of the main databases (Science Direct, PubMed, Scielo, Medline) between September 2015 and June 2016. Acne lesions create an environment that facilitates the excess growth of Propionibacterium acnes (P. acnes). AD is related to an increase in the proportion of Staphylococcus aureus (S. aureus) during flare-ups. Some microorganisms have been shown to act not only in the prevention but also in the competition for pathogenic microorganisms and beneficially affect the inflammatory process present in these conditions. Despite the high variety of tested bacteria, Staphylococcus, Streptococcus, Lactococcus, Lactobacillus, and Enterococcus are the ones which showed the highest potential to control acne, and Vitreoscilla filiformis (V. filiformis), Staphylococcus epidermidis (S. epidermidis), and species of Lactobacillus and Bifidobacterium in the treatment of AD. Many of these studies were in vitro, and more detailed research should be performed in order to prove the real efficacy and safety of probiotics in these situations. An interesting alternative seems to be the use of Bacteriocin-like inhibitory substances produced by probiotics, responsible for their antimicrobial activity.

Efficacy of local application of an Unani formulation in acne vulgaris

Background and Objectives:

Buthūr-i-Labaniyya (Acne vulgaris) is affecting up to 80% of adolescents and many adults at different stages of life. It is one of the commonest skin disorders which appears on cheeks and nose as white eruptions that seems like solidified milk drops. These eruptions are treated by drugs having properties of tajfīf wa taḥlīl (desiccant and resolving), as mentioned by Ibne Sina. Daood Antaki in his book Tazkira Oolulalbab recommends the local application of a paste of Shonīz (nigella sativa), Naushādar (ammonium chloride) and Būra Armani mixed with Sirka (vinegar) for effective treatment of Acne vulgaris.

Methods:

The study was observational self comparison before and after treatment, conducted in the OPD of the hospital which is part of the National Institute of Unani Medicine, Bangalore. The duration of study was one year. 40 Female patients with combination of comedones, papules, pustules and nodules were recruited for this purpose. The test drug, Shonīz, Būra Armani, Naushadar powder, mixed with sirka were applied locally for one month with taqlīl-i-ghidhā tadābīr (low calorie index diet). All subjects were assessed on the basis of changes in subjective and objective parameters.

Results:

The response of test drugs was statistically highly significant (P < 0.01) by using ANOVA repeated measure test, there was also relief in subjective parameters. Subjects reported a reduction of 82.6%, 80.9%, 66.6% in tenderness, itching and irritation respectively.

Interpretation and Conclusion:

The present study reveals that the test drug formulation is safe and effective in treating Acne vulgaris if used along with low calorie index diet. No side effects of drugs were reported, therefore the trial formulation can be recommended to manage Acne vulgaris of mild to severe degree as a therapy.

Progress in Malassezia Research in Korea

Yeasts of the genus Malassezia are part of the normal flora of human skin. However, they are also associated with various skin diseases. Since the introduction of Malassezia to the Korean Dermatologic Society two decades ago, remarkable progress has been made in our knowledge of this genus. In this paper, we review recent developments in Malassezia research, including taxonomy and methods for species identification, recent genome analyses, Malassezia species distribution in healthy conditions and in specific skin diseases, trials investigating the mechanisms underlying Malassezia-related diseases, as well as therapeutic options. This review will enhance our understanding of Malassezia yeasts and related skin diseases in Korea.

Malassezia-Can it be Ignored?

Genus Malassezia comprises of 14 species of “yeast like fungi,” 13 of which are lipophilic and 1 is nonlipophilic. They are known commensals and in predisposed individuals they commonly cause a spectrum of chronic recurrent infections. They rarely also cause serious illnesses like catheter-related blood stream infections, CAPD associated peritonitis etc., Though these fungi have been known to man for over 150 years, their fastidious nature and cumbersome culture and speciation techniques have restricted research. Since the last taxonomic revision, seven new species have been added to this genus. Their ability to evade the host immune system and virulence has increased the spectrum of the diseases caused by them. These agents have been implicated as causal agents in common diseases like atopic dermatitis recently. Though culture-based research is difficult, the new molecular analysis techniques and facilities have increased research in this field such that we can devote more attention to this genus to study in detail, their characteristics and their growing implications implications in the clinical scenario.

Analysis of facial skin-resident microbiota in Japanese acne patients

OBJECTIVES

We investigated the facial skin microbiota of Japanese acne patients.

METHODS

Skin swab samples were obtained from 100 acne patients and 28 healthy controls to evaluate Propionibacterium and Staphylococcus spp. using a culture method. Malassezia spp. were evaluated using a nonculture method. Antibiotic resistance of Propionibacterium spp. was also examined.

RESULTS

Acne patients and controls did not show significant differences in Propionibacterium and Staphylococcus spp. populations. However, the number of Malassezia globosa from patients was greater than that from controls. Moreover, the number of Propionibacterium spp. from patients carrying antibiotic-resistant strains was significantly greater than that from patients not carrying them.

CONCLUSIONS

The present study characterized the facial skin microbiota of Japanese acne patients, suggesting a correlation between acne and quantitative differences in Malassezia microbiota. It was also found that the antibiotic resistance of Propionibacterium spp. may affect its abundance in the skin.