OBJECTIVE: To investigate the therapeutic efficacy of cinnamaldehyde (CA) on systemic Candida albicans infection in mice and to provide supportive data for the development of novel antifungal drugs. METHODS: Ninety BALB/c mice were randomly divided into 3 groups according to a random number table: CA treatment group, fluconazole (positive control) group, and Tween saline (negative control) group, with 30 mice in each group. Initially, all groups of mice received consecutive intraperitoneal injections of cyclophosphamide at 200 mg/kg for 2 days, followed by intraperitoneal injection of 0.25 mL C. albicans fungal suspension (concentration of 1.0 × 10⁷ CFU/mL) on the 4th day, to establish an immunosuppressed systemic Candida albicans infection animal model. Subsequently, the mice were orally administered CA, fluconazole and Tween saline, at 240, 240 mg/kg and 0.25 mL/kg respectively for 14 days. After a 48-h discontinuation of treatment, the liver, small intestine, and kidney tissues of mice were collected for fungal direct microscopic examination, culture, and histopathological examination. Additionally, renal tissues from each group of mice were collected for (1,3)- β -D-glucan detection. The survival status of mice in all groups was monitored for 14 days of drug administration. RESULTS: The CA group exhibited a fungal clearance rate of C. albicans above 86.7% (26/30), significantly higher than the fluconazole group (60.0%, 18/30, P<0.01) and the Tween saline group (30.0%, 9/30, P<0.01). Furthermore, histopathological examination in the CA group revealed the disappearance of inflammatory cells and near-normal restoration of tissue structure. The (1,3)-β-D-glucan detection value in the CA group (860.55 ± 126.73 pg/mL) was significantly lower than that in the fluconazole group (1985.13 ± 203.56 pg/mL, P<0.01) and the Tween saline group (5910.20 ± 320.56 pg/mL, P<0.01). The mouse survival rate reached 90.0% (27/30), higher than the fluconazole group (60.0%, 18/30) and the Tween saline group (30.0%, 9/30), with a significant difference between the two groups (both P<0.01). CONCLUSIONS CA treatment exhibited significant therapeutic efficacy in mice with systemic C. albicans infection. Therefore, CA holds potential as a novel antifungal agent for targeted treatment of C. albicans infection.
Animals ; Acrolein/pharmacology* ; Candida albicans/physiology* ; Mice, Inbred BALB C ; Candidiasis/pathology* ; Antifungal Agents/therapeutic use* ; Mice ; Fluconazole/therapeutic use* ; Kidney/drug effects* ; Female

OBJECTIVE: To map the potent antifungal properties of the medicinal plant Vitex negundo, in vitro and in silico studies were performed to decipher the pharmacokinetics and ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) properties of their phytoconstituents. METHODS: With the PASS (Prediction of Activity Spectra for Substances) prediction tool, many parameters of V. negundo phenolics were examined, including drug-likeness, bioavailability, antifungal activity, and anti-biofilm activity. Moreover, ADMET parameters were also determined. RESULTS: Eighteen phenolic compounds from V. negundo with significant antifungal activity against Candida species (human fungal pathogens) were detected. The antioxidant activity, inhibition percentage, and minimum inhibitory concentration value of V. negundo phenolic extracts indicate it as an effective antifungal agent for the treatment of candidiasis caused by the fungal pathogen Candida albicans. Many phenolic compounds showed a significantly high efficiency against Candida's planktonic cells and biofilm condition. CONCLUSIONS The phenolics fraction of V. negundo has potent antifungal activities, however, some more pre-clinical studies are a matter of future research to further investigate V. negundo phenolic compound as a potential new antifungal arsenal.
Candida albicans/physiology* ; Vitex/chemistry* ; Antifungal Agents/chemistry* ; Microbial Sensitivity Tests ; Biofilms/drug effects* ; Phenols/pharmacokinetics* ; Plant Extracts/chemistry* ; Antioxidants/pharmacology* ; Phytochemicals/pharmacology* ; Humans

OBJECTIVES: To explore the efficacy of low-intensity pulsed ultrasound (LIPUS) combined with nystatin for treatment of vaginal Candida albicans biofilm infection. METHODS: In vitro cultured Candida albicans biofilm were treated with LIPUS, nystatin, or both, and the minimum inhibitory concentration (MIC) of nystatin was determined. Crystal violet staining, confocal laser microscopy (CLSM) and scanning electron microscopy were used to quantify the biofilm and observe the activity and morphological changes of the biofilms; DCFH-DA was used to detect the changes in reactive oxygen species (ROS). Twenty female New Zealand White rabbits with vaginal inoculation of Candida albicans biofilm were randomized into 4 groups for treatment with normal saline, LIPUS, nystatin, or both LIPUS and nystatin. The changes in vulvar symptoms of the rabbits were observed, and the histopathological and ultrastructural changes of the vagina before and after treatment were observed using HE staining and transmission electron microscopy. RESULTS: In the combined treatment group, the MIC₅₀ and MIC₈₀ of nystatin in Candida albicans biofilms were both reduced by 50% compared with those in nystatin group, and the biofilm clearance rate increased by 26% and 68% compared with nystatin and LIPUS groups, respectively. Compared with nystatin and LIPUS treatment alone, the combined treatment produced stronger effects for inhibiting biofilm activity, causing structural disruption and promoting ROS production. In the rabbit models, the combined treatment more effectively improved vulvar symptoms and inflammatory infiltration, reduced residual vaginal hyphae/strains, and improved ultrastructure of the vaginal epithelium than LIPUS and nystatin treatment alone. CONCLUSIONS LIPUS combined with nystatin produces a significant synergistic antifungal effect against Candida albicans biofilm both in vitro and in vivo.
Animals ; Rabbits ; Female ; Biofilms/drug effects* ; Candida albicans/physiology* ; Nystatin/therapeutic use* ; Candidiasis, Vulvovaginal/microbiology* ; Ultrasonic Waves ; Antifungal Agents/therapeutic use* ; Vagina/microbiology* ; Ultrasonic Therapy ; Microbial Sensitivity Tests ; Combined Modality Therapy

OBJECTIVE: To evaluate the synergy of the Burkholderia signaling molecule cis-2-dodecenoic acid (BDSF) and fluconazole (FLU) or itraconazole (ITRA) against two azole-resistant C. albicans clinical isolates in vitro and in vivo. METHODS: Minimum inhibitory concentrations (MICs) of antibiotics against two azole-resistant C. albicans were measured by the checkerboard technique, E-test, and time-kill assay. In vivo antifungal synergy testing was performed on mice. Analysis of the relative gene expression levels of the strains was conducted by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). RESULTS: BDSF showed highly synergistic effects in combination with FLU or ITRA with a fractional inhibitory concentration index of ⪕ 0.08. BDSF was not cytotoxic to normal human foreskin fibroblast cells at concentrations of up to 300 μg/mL. The qRT-PCR results showed that the combination of BDSF and FLU/ITRA significantly inhibits the expression of the efflux pump genes CDR1 and MDR1 via suppression of the transcription factors TAC1 and MRR1, respectively, when compared with FLU or ITRA alone. No dramatic difference in the mRNA expression levels of ERG1, ERG11, and UPC2 was found, which indicates that the drug combinations do not significantly interfere with UPC2-mediated ergosterol levels. In vivo experiments revealed that combination therapy can be an effective therapeutic approach to treat candidiasis. CONCLUSION The synergistic effects of BDSF and azoles may be useful as an alternative approach to control azole-resistant Candida infections.
Antifungal Agents ; pharmacology ; Burkholderia cenocepacia ; chemistry ; Candida albicans ; drug effects ; physiology ; Candidiasis ; drug therapy ; Drug Resistance, Fungal ; Fatty Acids, Monounsaturated ; adverse effects ; Fluconazole ; pharmacology ; Humans ; Microbial Sensitivity Tests ; Triazoles ; metabolism

OBJECTIVE: To evaluate the efficacy of cis-2-dodecenoic acid (BDSF) in the treatment and prevention of vaginal candidiasis in vivo. METHODS: The activities of different concentrations of BDSF against the virulence factors of Candida albicans (C. albicans) were determined in vitro. An experimental mouse model of Candida vaginitis was treated with 250 μmol/L BDSF. Treatment efficiency was evaluated in accordance with vaginal fungal burden and inflammation symptoms. RESULTS: In vitro experiments indicated that BDSF attenuated the adhesion and damage of C. albicans to epithelial cells by decreasing phospholipase secretion and blocking filament formation. Treatment with 30 μmol/L BDSF reduced the adhesion and damage of C. albicans to epithelial cells by 36.9% and 42.3%, respectively. Treatment with 200 μmol/L BDSF completely inhibited phospholipase activity. In vivo mouse experiments demonstrated that BDSF could effectively eliminate vaginal infection and relieve inflammatory symptoms. Four days of treatment with 250 μmol/L BDSF reduced vaginal fungal loads by 6-fold and depressed inflammation. Moreover, BDSF treatment decreased the expression levels of the inflammatory chemokine-associated genes MCP-1 and IGFBP3 by 2.5- and 2-fold, respectively. CONCLUSION BDSF is a novel alternative drug that can efficiently control vaginal candidiasis by inhibiting the virulence factors of C. albicans.
Animals ; Candida albicans ; drug effects ; metabolism ; pathogenicity ; physiology ; Candidiasis, Vulvovaginal ; drug therapy ; genetics ; immunology ; microbiology ; Chemokine CCL2 ; genetics ; immunology ; Disease Models, Animal ; Fatty Acids, Monounsaturated ; administration & dosage ; Female ; Fungal Proteins ; genetics ; metabolism ; Humans ; Insulin-Like Growth Factor Binding Protein 3 ; genetics ; immunology ; Mice ; Virulence ; drug effects ; Virulence Factors ; genetics ; metabolism

BACKGROUNDVulvovaginal candidiasis is caused by Candida albicans. The vaginal epithelium, as the first site of the initial stage of infection by pathogens, plays an important role in resisting genital tract infections. Moreover, lactobacilli are predominant members of the vaginal microbiota that help to maintain a normal vaginal microenvironment. Therefore, Lactobacillus crispatus was explored for its capacity to intervene in the immune response of vaginal epithelial cells VK2/E6E7 to C. albicans.

METHODSWe examined the interleukin-2 (IL-2), 4, 6, 8, and 17 produced by VK2/E6E7 cells infected with C. albicans and treated with L. crispatus in vitro. The capacity of L. crispatus to adhere to VK2/E6E7 and inhibit C. albicans growth was also tested by scanning electron microscopy (SEM) and adhesion experiments.

RESULTSCompared with group VK2/E6E7 with C. albicans, when treated with L. crispatus, the adhesion of C. albicans to VK2/E6E7 cells decreased significantly by 52.87 ± 1.22%, 47.03 ± 1.35%, and 42.20 ± 1.55% under competition, exclusion, and displacement conditions, respectively. SEM revealed that the invasion of C. albicans into VK2/E6E7 cells was caused by induced endocytosis and active penetration. L. crispatus could effectively protect the cells from the virulence of hyphae and spores of C. albicans and enhance the local immune function of the VK2/E6E7 cells. The concentrations of IL-2, 6, and 17 were upregulated significantly (P < 0.01) and that of IL-8 were downregulated significantly (P < 0.01) in infected VK2/E6E7 cells treated with L. crispatus. The concentration of IL-4 was similar to that of the group VK2/E6E7 with C. albicans (24.10 ± 0.97 vs. 23.12 ± 0.76 pg/ml, P = 0.221).

CONCLUSIONSL. crispatus can attenuate the virulence of C. albicans, modulate the secretion of cytokines and chemokines, and enhance the immune response of VK2/E6E7 cells in vitro. The vaginal mucosa has a potential function in the local immune responses against pathogens that can be promoted by L. crispatus.

Candida albicans ; pathogenicity ; Cell Line, Tumor ; Epithelial Cells ; immunology ; metabolism ; microbiology ; ultrastructure ; Female ; Humans ; Interleukin-17 ; metabolism ; Interleukin-2 ; metabolism ; Interleukin-4 ; metabolism ; Interleukin-6 ; metabolism ; Interleukin-8 ; metabolism ; Lactobacillus crispatus ; physiology ; Microscopy, Electron, Scanning ; Vagina ; cytology

Amphibian skin contains rich bioactive peptides. Especially, a large amount of antimicrobial peptides have been identified from amphibian skin secretions. Antimicrobial peptides display potent cytolytic activities against a range of pathogenic bacteria and fungi and play important defense roles. No antimicrobial peptides have been reported from toads belonging to the family of Pelobatidae. In this work, two novel antimicrobial peptides (Megin 1 and Megin 2) were purified and characterized from the skin venoms of spadefoot toad Megophrys minor (Pelobatidae, Anura, Amphibia). Megin 1 had an amino acid sequence of FLKGCWTKWYSLKPKCPF-NH2, which was composed of 18 amino acid residues and contained an intra-molecular disulfide bridge and an amidated C-terminus. Megin 2 had an amino acid sequence of FFVLKFLLKWAGKVGLEHLACKFKNWC, which was composed of 27 amino acid residues and contained an intra-molecular disulfide bridge. Both Megin 1 and Megin 2 showed potential antimicrobial abilities against bacteria and fungi. The MICs of Megin 1 against Escherichia coli, Bacillus dysenteriae, Staphylococcus aureus, Bacillus subtilis, and Candida albicans were 25, 3, 6.25, 3, and 50 μg·mL(-1), respectively. The corresponding MICs for Megin 2 were 6.25, 1.5, 12.5, 1.5, and 12.5 μg·mL(-1), respectively. They also exerted strong hemolytic activity against human and rabbit red cells. The results suggested that megin peptides in the toad skin of M. minor displayed toxic effects on both eukaryotes and prokaryotes. This was the first report of antimicrobial peptides from amphibians belonging to the family of Pelobatidae.
Amino Acid Sequence ; Amphibian Venoms ; chemistry ; immunology ; isolation & purification ; Animals ; Anura ; immunology ; Bacillus ; Candida albicans ; Erythrocytes ; physiology ; Escherichia coli ; Female ; Hemolysis ; Humans ; Male ; Peptides ; chemistry ; immunology ; isolation & purification ; Rabbits ; Sequence Alignment ; Skin ; chemistry ; immunology ; Staphylococcus aureus

OBJECTIVETo investigate the effect of andrographolide (AG) on quroum sensing (QS) and relevant virulence genes of Candida albicans.

METHODGas-chromatography-mass spectrometry (GC-MS) was applied to detect the changes in the content of farnesol and tyrosol in C. albicans intervened by AG. The real-time quantitative PCR (qRT-PCR) was adopted to inspect the expressions of relevant virulence genes such as CHK1, PBS2 and HOG1 regulated by QS.

RESULTAt 2 h after the growth of C. albican, the farnesol and tyrosol secretions reduced, without notable change after intervention with AG. The secretions were highest at 12 h and decreased at 24 h. After the intervention with different concentrations of AG, the farnesol content reduces, whereas tyrosol increased, indicating a dose-dependence, particularly with 1 000 mg x L(-1) AG. qRT-PCR revealed that 1 000 mg x L(-1) AG could down-regulate CHK1 by 2.375, 3.330 and 4.043 times and PBS2 by 2.010, 4.210 and 4.760 times, with no significant change in HOG1.

CONCLUSIONAG could inhibit the farnesol secretion, promote the tyrosol secretion and down-regulate QS-related virulence genes CHK1 and PBS2 expressions.

Candida albicans ; drug effects ; genetics ; physiology ; Diterpenes ; pharmacology ; Farnesol ; analysis ; metabolism ; Gas Chromatography-Mass Spectrometry ; Genes, Fungal ; Phenylethyl Alcohol ; analogs & derivatives ; analysis ; metabolism ; Quorum Sensing ; drug effects ; Real-Time Polymerase Chain Reaction ; Virulence ; genetics

OBJECTIVETo investigate the effect of andrographolide derivative Yanhuning (YHN) on Candida albicans biofilms in rats.

METHODThe rat C. albicans biofilms subcutaneous catheter model was established by intraperitoneally injecting YHN (40, 20, 10, 5, 2.5 mg x kg (-1)), with the FLC (80 mg x kg(-1)) positive group as the control group. After 7 d, CFU counting and XTT assay were used to evaluate the effect of YHN on C. albicans biofllms in vivo. Scanning electron microscopy (SEM) was applied to observe the morphological changes in rat biofilms intervened by YHN. The real-time fluorescence quantification PCR was adopted to detect expressions of C. albicans adhesion-related genes, such as ALS1, ALS3, HWP1, EAP1 and MP65.

RESULTThe YHN group showed much less CFUs on catheter pieces and lower XTT metabolic activity than the blank group, with dosage dependence. SEM also showed that YHN could obviously decrease C. albicans adhesion on subcutaneous catheters in rats. According to qRT-PCR's results, YHN can down-regulate expressions of ALS1, ALS3, HWP1, EAP1 and MP65.

CONCLUSIONYHN could inhibit C. albicans biofilms in rats.

Animals ; Biofilms ; drug effects ; growth & development ; Candida albicans ; cytology ; drug effects ; physiology ; Catheters ; microbiology ; Cell Adhesion ; drug effects ; Diterpenes ; chemistry ; pharmacology ; Dose-Response Relationship, Drug ; Rats

Along with the increase in fungal infections, Candida albicans prevention and control become the focus of anti-fungal infection at present. This study aims to discuss the effect monomer andrographolide (AG) on C. albicans biofilm dispersion. In the experiment, micro-well plates and medical catheter pieces were used to establish the C. albicans biofilm model. It was discovered by XTT assay and flat band method that 1 000, 500, 250 mg x L(-1) AG could impact the activity of C. albicans biofilm dispersion cells. The morphological structures of residual biofilms on catheter pieces were observed with scanning electron microscopy, which showed that 1 000, 500, 250 mg x L(-1) AG could induce C. albicans biofilm dispersion in a dose-dependent manner, and the dispersed cells were dominated by the yeast phase. According to the real-time fluorescence quantification PCR (qRT-PCR) test, AG could up-regulate HSP90 expression and down-regulate UME6 and PES1 expressions. This study demonstrates that AG could induce C. albicans biofilm dispersion to some extent.
Anti-Inflammatory Agents ; pharmacology ; Biofilms ; drug effects ; Candida albicans ; genetics ; physiology ; ultrastructure ; Diterpenes ; pharmacology ; Dose-Response Relationship, Drug ; Fungal Proteins ; genetics ; Gene Expression Regulation, Fungal ; drug effects ; HSP90 Heat-Shock Proteins ; genetics ; Microscopy, Electron, Scanning ; Reverse Transcriptase Polymerase Chain Reaction ; Time Factors