Cutaneous Reactivity to Malassezia Pachydermatis in Dogs with Seborrheic Dermatitis

Masahiko Nagata

doi:10.2736/jjvd.9.67

Fungi of the genus Malassezia as opportunists of humans and animals

Postępy Higieny i Medycyny Doświadczalnej ◽

10.5604/01.3001.0011.8256 ◽

2018 ◽

Vol 72 ◽

pp. 359-375 ◽

Cited By ~ 1

Author(s):

Urszula Czyżewska ◽

Magdalena Siemieniuk ◽

Marek Bartoszewicz ◽

Adam Tylicki

Keyword(s):

Extracellular Enzymes ◽

Cell Structure ◽

Seborrheic Dermatitis ◽

Epidemiological Data ◽

Protein Profiling ◽

Specific Cell ◽

Malassezia Pachydermatis ◽

Malassezia Folliculitis ◽

Malassezia Spp

Yeasts from the genus Malassezia are common commensals and pathogens found in humans and animals, and are responsible for tinea cases. Due to their specific cell structure, they may be resistant to environmental stresses and difficult to eliminate by the host’s immune system. In spite of several virulence factors, the pathogenicity of Malassezia spp. and their interactions with hosts still arouse great interest. Genomes of particular isolates, representing the majority of species from the Malassezia genus, have been sequenced in recent years. Moreover, reconstruction of the phylogeny, by the usage of ITS and IGS sequences, has been attempted as well. Biochemical analyzes led to a better understanding of those fungi’s ecology and virulence. Lipid and protein profiling, the assessment of phospholipases and extracellular enzymes activities, brought new insight into the genesis and courses of diverse illnesses, including pityriasis versicolor, seborrheic dermatitis, atopic dermatitis, Malassezia folliculitis, psoriasis and systemic fungemia. Special attention should be paid to Malassezia pachydermatis, which is a potential model of zoophilic species with an increasing frequency of tinea cases caused in humans. Furthermore, in vitro experiments suggest its possible drug resistance. The members of Malassezia genus are a serious medical and therapeutic challenge. Because of difficulties in the assessment of their virulence, high genetic and biochemical diversity and, finally, complicated evolutionary traits, they require further research. Genomic and proteomic analyses, supported with biochemical profiling and epidemiological data, will contribute to a better understanding of the biology of the yeasts, especially the issue of opportunism among fungi.

Download Full-text

Inhibitory Effects of Sulfonamide Derivatives on the β-Carbonic Anhydrase (MpaCA) from Malassezia pachydermatis, a Commensal, Pathogenic Fungus Present in Domestic Animals

International Journal of Molecular Sciences ◽

10.3390/ijms222212601 ◽

2021 ◽

Vol 22 (22) ◽

pp. 12601

Author(s):

Viviana De Luca ◽

Andrea Angeli ◽

Valeria Mazzone ◽

Claudia Adelfio ◽

Fabrizio Carta ◽

...

Keyword(s):

Pathogenic Fungus ◽

Seborrheic Dermatitis ◽

Co2 Concentration ◽

Carbonic Anhydrases ◽

Medical Sciences ◽

Inhibitory Effects ◽

Malassezia Pachydermatis ◽

Sensing Systems ◽

Promising Target ◽

Reversible Hydration

Fungi are exposed to various environmental variables during their life cycle, including changes in CO2 concentration. CO2 has the potential to act as an activator of several cell signaling pathways. In fungi, the sensing of CO2 triggers cell differentiation and the biosynthesis of proteins involved in the metabolism and pathogenicity of these microorganisms. The molecular machineries involved in CO2 sensing constitute a promising target for the development of antifungals. Carbonic anhydrases (CAs, EC 4.2.1.1) are crucial enzymes in the CO2 sensing systems of fungi, because they catalyze the reversible hydration of CO2 to proton and HCO3-. Bicarbonate in turn boots a cascade of reactions triggering fungal pathogenicity and metabolism. Accordingly, CAs affect microorganism proliferation and may represent a potential therapeutic target against fungal infection. Here, the inhibition of the unique β-CA (MpaCA) encoded in the genome of Malassezia pachydermatis, a fungus with substantial relevance in veterinary and medical sciences, was investigated using a series of conventional CA inhibitors (CAIs), namely aromatic and heterocyclic sulfonamides. This study aimed to describe novel candidates that can kill this harmful fungus by inhibiting their CA, and thus lead to effective anti-dandruff and anti-seborrheic dermatitis agents. In this context, current antifungal compounds, such as the azoles and their derivatives, have been demonstrated to induce the selection of resistant fungal strains and lose therapeutic efficacy, which might be restored by the concomitant use of alternative compounds, such as the fungal CA inhibitors.

Download Full-text

Genotipificação de Malassezia pachydermatis através da técnica de RAPD

Semina Ciências Agrárias ◽

10.5433/1679-0359.2016v37n5p3173 ◽

2016 ◽

Vol 37 (5) ◽

pp. 3173

Author(s):

Franciele Cristina Kagueyama ◽

Danny Franciele Dias Moraes ◽

Janaina Marcela Assunção Rosa ◽

Alessandra Tammy Hayakawa Ito ◽

Aline De Jesus da Silva ◽

...

Keyword(s):

Seborrheic Dermatitis ◽

Clinical Signs ◽

Domestic Cat ◽

Domestic Dog ◽

Human Beings ◽

Malassezia Pachydermatis ◽

Genomic Polymorphism ◽

Sabouraud Agar ◽

Yeast Cultures ◽

Type Iv

Malassezia pachydermatis (M. pachydermatis) is a fungus of importance in human and veterinary medicine. Although a part of the normal microbiota, it can sometimes be present in its pathogenic form, particularly causing otitis and dermatitis in animals. Among human beings, it mainly affects immune compromised patients and newborns, causing simple pustulosis, seborrheic dermatitis, tinea versicolor or fungemia. This study aimed to analyze the genomic polymorphism in M. pachydermatis samples isolated from Canis familiaris (domestic dog), Felis catus (domestic cat), and Myrmecophaga tridactyla (giant anteater). Two hundred and fourteen samples were collected and cultured in Sabouraud agar with chloranphenicol (100mg L-1) and incubated at 37 °C for a period of 7 to 10 days. One hundred and sixty six samples that appeared morphologically comparable to yeast cultures were processed for DNA extraction and PCR was performed for a specific region in the Internal Transcribed Spacer (ITS) of M. pachydermatis. Among these, seven (4.21%) were negative and 159 (95.79%) were positive. Of the 159 positive samples, 102 (64.15%) were from animals with clinical signs and 57 (35.85%) without clinical signs. Fifty-seven samples were selected at random for RAPD-PCR based genotyping and distributed into four genetic groups. Types I and II were more frequent in animals with clinical signs while type III was frequent in healthy animals. Type IV occurred evenly across animals with or without clinical signs. These results indicate differences in pathogenicity of the fungus based on the genotype.

Download Full-text