RESUMO
OBJECTIVE: The purpose of this study was to evaluate the effects of Trachyspermum copticum (T. copticum) essential oil and propolis alcoholic extract on growth and transcription of Mep3 gene of Microsporum canis (M. canis) strains. METHODS: The antifungal activity was assayed by broth macrodilution method. Fungal isolates were grown in soy peptone liquid medium and treated with T. copticum oil and propolis extract. Total RNAs of M. canis were subjected to reverse transcription-polymerase chain reaction (RT-PCR). Specific primers of Actin and Mep3 genes were used. RESULTS: The results revealed that MIC values of T. copticum oil against M. canis strains were ranged from 0.2-30.5 µg/mL, with 42.3% of the strains inhibited at 0.9 µg/mL. In addition, MIC values of propolis extract against M. canis strains were ranged from 0.2-488.2 µg/mL, with 34.6% of the strains inhibited at 0.9 µg/mL. RT-PCR analysis of Mep3 and Actin expression showed DNA fragments of 661 and 690 bp amplified in all isolates before treatments with T. copticum essential oil and propolis extract. Both T. copticum and propolis completely inhibited the expression of Mep3 gene. CONCLUSION: We reported for the first time that T. copticum and propolis inhibits the expression of Mep3 gene in M. canis strains in relation to a remarkable inhibition in protease production by the fungus.