Résumé
OBJECTIVE@#To evaluate the effect and safety of cinnamaldehyde on immunosuppressed mice with invasive pulmonary candidiasis.@*METHODS@#An immunosuppressed BALB/c mouse model was established by intraperitoneal administration of cyclophosphamide (200 mg/kg) once daily for 2 days. The immunosuppressed mouse with invasive pulmonary candidiasis model was further established by nasal perfusion of Candida albicans suspension. In the cinnamaldehyde treatment group, immunosuppressed mice with invasive pulmonary candidiasis were orally given cinnamaldehyde 240 mg/(kg·d) for 14 consecutive days. Fluconazole and 0.9% saline were used as the positive and negative controls, respectively. The mice in the cinnamaldehyde safety evaluation group were orally administered cinnamaldehyde 480 mg/(kg·d) for 42 days to observe the safety of the drug. Microscopic identification, fungal culture, histopathological examination, and (1,3)-beta-D-glucans detection were conducted to analyze the effect of cinnamaldehyde on C. albicans.@*RESULTS@#The fungal clearance rate in the cinnamaldehyde treatment group was higher than that in the fluconazole control group (80.00% vs. 56.67%, P<0.05). The level of (1,3)-β-D-glucan in the cinnamaldehyde treatment group was lower than that in the fluconazole positive control group (1160.62 ±89.65 pg/mL vs. 4285.87 ± 215.62 pg/mL, P<0.05). The survival rate of mice in the cinnamaldehyde safety evaluation group was 100%, and no significant pathological changes of kidney, lung and liver were observed.@*CONCLUSIONS@#Cinnamaldehyde was effective and safe in treating immunosuppressed BALB/c mice with invasive pulmonary candidiasis. It would be a potentially novel drug for anti-candidiasis infection.
Résumé
Objective: Invasive pulmonary candidiasis is a disease with high incidence, difficult treatment, poor prognosis, and high mortality. The present study analyzed the influence of cinnamaldehyde on 1,3-β-D-glucans in the cell wall of Candida albicans in order to provide a theoretical basis for the research of antifungal drugs. Methods: An immunosuppressed BALB/c mouse model with invasive pulmonary candidiasis was established by nasal perfusion of 50 µL of C. albicans suspension (107 cfu/mL). 1,3-β-D-glucans examination and electron microscopy were carried out. Fluconazole was used as the control. Results: Cinnamaldehyde was administered at a dose of 240 mg/kg/d for 14 consecutive days, and the measured value of 1,3-β-D-glucans was (1160.62 ± 89.65) pg/mL, whereas that of fluconazole was (4285.87 ± 215.62) pg/mL. The difference between the two groups was statistically significant (P < 0.05). Electron microscopy observation indicated that the 2−3 layers outside the cell wall of C. albicans (1,3-β-D-glucans layer) were rough, deformed, and incomplete, although the cell membrane was clear and intact. Conclusion: Cinnamaldehyde demonstrated special efficacy on 1,3-β-D-glucans in the cell wall of C. albicans.