Molecular characterization of Candida dubliniensis and Candida albicans in the oral cavity of drug abusers using duplex polymerase chain reaction

Exploring the diversity of uncommon oral yeast species and associated risk factors among substance abusers in southwestern Iran

Yeast species are a group of coexistent microorganisms in the oral cavity that can cause opportunistic infections in vulnerable individuals, including addicts. This study aimed to identify the yeast species profile responsible for oral yeast colonization (OYC) and the associated risk factors in patients with substance use disorder (SUD) in Ahvaz, Iran. Oral samples were collected from drug users hospitalized in 12 addiction treatment centers, and the related clinical information was mined. Oral yeast species were identified using 21-plex PCR and sequencing of the internal transcribed spacer region (ITS1-5.8S-ITS2). A total of 244 yeast strains were identified from 245 individuals with substance abuse. Candida albicans was the most common species (37.7%) and non-albicans Candida was responsible for 57.7% of OYC, primarily C. dubliniensis (33.2%) and C. glabrata (11.9%). Moreover, uncommon oral yeasts constituted 5.3% of species, including Saccharomyces cerevisiae, Clavispora lusitaniae, Pichia kluyveri, Geotrichum candidum, Magnusiomyces capitatus, Hanseniospora opuntiae, Wickerhamomyces subpelliculosus, Trichosporon asahii, and Aureobasidium pullulans. Importantly, OYC exhibited associations with such factors as duration of drug use, daily drug consumption rate, opioid utilization, oral drug administration, and the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) score. The present study is the pioneering investigation revealing the prevalence and diversity of oral yeast species, along with associated risk factors, in individuals with SUD in southwestern Iran. Furthermore, it underscores the importance of developing efficient and cost-effective diagnostic methods tailored for resource-constrained settings.

Frequency of Candida Species in the Oral Cavity of Narcotics and Stimulants Smokers in Isfahan, Using Polymerase Chain Reaction-Restriction Fragment Length Polymorphism Method

Background:

Candida species are a group of coexistent microorganisms in the oral cavity that opportunistically cause disease in vulnerable people, including addicts. This study is aimed at identifying and determining the frequency of Candida species in the oral cavity of the addicts to inform the epidemiological panel and to warn to prevent the resistance of the species.

Materials and Methods:

In this study, sampling was done from the oral cavity of 83 addicts who referred to Addiction Treatment Centers in Isfahan, Iran, using moist sterile swab. The presence of yeast on the direct microscope slides of 58 samples was confirmed. To carry out culture and the primary identification, Sabouraud dextrose agar medium with chloramphenicol as well as HiCrome Candida agar medium was used. Isolates were identified by polymerase chain reaction (PCR) restriction fragment length polymorphism (using specific primers ITS1-ITS4 and MSP I enzyme) and Duplex PCR test (using specific primers CDU1-CDU2/CAL1-CAL2).

Results:

Out of 93 Candida isolates which had been isolated from 58 culture-positive samples of the oral cavity, Candida albicans (41.93%) were the most prevalent species, followed by Candida dubliniensis (24.73%), Candida glabrata (21.50%), Candida kefyr (8.60%), Candida tropicalis (2.15%), and Candida parapsilosis (1.07%), respectively. In 33 cases (56.90%), the presence of more than one Candida species was observed.

Conclusion:

Compared to the studies conducted on the oral cavity of healthy controls, smoking certain drugs can have a significant effect on the presence and frequency of Candida species, particularly C. dubliniensis and C. glabrata.

Lepidine B & E as New Target Inhibitors from Lepidium Sativum Seeds Against Four Enzymes of the Pathogen Candida albicans: In Vitro and In Silico Studies

BACKGROUND AND OBJECTIVE

The present paper aims to study the inhibition of Candida albicans growth as candidiasis treatment, using seeds of Lepidium sativum as source.

METHODS

In vitro assays were carried out on the antifungal activity of three kinds of extracts from L. sativum seeds against four strains of C. albicans, then testing the same phytochemicals on the inhibition of Lipase (LCR). A new in silico study was achieved using molecular docking, with Autodock vina program, to find binding affinity of two important and major lepidine alkaloids (lepidine E and B) towards the four enzymes secreted by C. albicans as target drugs, responsible of vitality and virulence of this yeast cells: Lipase, Serine/threonine phosphatase, Phosphomannose isomerase and Sterol 14-alpha demethylase (CYP51).

RESULTS

The results of the microdillution assay show that the hexanic and alkaloidal extracts have an antifungal activity with MICs: 2.25 mg/ml and 4.5mg/ml, respectively. However, Candida rugosa lipase assay gives a remarkable IC50 values for the hexanic extract (1.42± 0.04 mg/ml) followed by 1.7± 0.1 and 2.29 ± 0.09 mg/ml of ethyl acetate and alkaloidal extracts respectively. The molecular docking confirms a significant correlation between C. albicans growth and inhibition of crucial enzymes involved in the invasion mechanism and cellular metabolisms, for the first time there were an interesting and new positive results on binding modes of lepidine E and B on the four studied enzymes.

CONCLUSION

Through this work, we propose Lepidine B & E as potent antifungal drugs.