Candida albicans is one of the major causes of invasive fungal infections and a serious opportunistic pathogen in immunocompromised individuals. The antimicrobial peptide AMP-17 has prominent anti-Candida activity, and proteomic analysis revealed significant differences in the expression of cell wall (XOG1) and oxidative stress (SRR1) genes upon the action of AMP-17 on C. albicans, suggesting that AMP-17 may exert anti-C. albicans effects by affecting the expression of XOG1 and SRR1 genes. To further investigate whether XOG1 and SRR1 genes were the targets of AMP-17, C. albicans xog1Δ/Δ and srr1Δ/Δ mutants were constructed using the clustered regulatory interspaced short palindromic repeats-associated protein 9 (CRISPR/Cas9) system. Phenotypic observations revealed that deletion of two genes had no significant effect on C. albicans growth and biofilm formation, whereas XOG1 gene deletion affected in vitro stress response and mycelium formation of C. albicans. Drug sensitivity assay showed that the MIC₈₀ values of AMP-17 against xog1Δ/Δ and srr1Δ/Δ mutants increased from 8 μg/mL (for the wild type C. albicans SC5314) to 16 μg/mL, while the MIC₈₀ values against srr1Δ/Δ: : srr1 revertants decreased to the level of the wild type SC5314. In addition, the ability of AMP-17 to inhibit biofilm formation of both deletion strains was significantly reduced compared to that of wild type SC5314, indicating that the susceptibility of the deletion mutants to AMP-17 was reduced in both the yeast state and during biofilm formation. These results suggest that XOG1 and SRR1 genes are likely two of the potential targets for AMP-17 to exert anti-C. albicans effects, which may facilitate further exploration of the antibacterial mechanism of novel peptide antifungal drugs.
Humans ; Candida albicans ; Antimicrobial Peptides ; Proteomics ; Peptides/pharmacology* ; Transcription Factors/metabolism* ; Antifungal Agents/pharmacology*

This study aimed to explore the mechanism of n-butanol alcohol extract of Baitouweng Decoction(BAEB) in the treatment of vulvovaginal candidiasis(VVC) in mice based on the negative regulation of NLRP3 inflammasome via PKCδ/NLRC4/IL-1Ra axis. In the experiment, female C57BL/6 mice were divided randomly into the following six groups: a blank control group, a VVC model group, high-, medium-, and low-dose BAEB groups(80, 40, and 20 mg·kg~(-1)), and a fluconazole group(20 mg·kg~(-1)). The VVC model was induced in mice except for those in the blank control group by the estrogen dependence method. After modeling, no treatment was carried out in the blank control group. The mice in the high-, medium-, and low-dose BAEB groups were treated with BAEB at 80, 40, and 20 mg·kg~(-1), respectively, and those in the fluconazole group were treated with fluconazole at 20 mg·kg~(-1). The mice in the VVC model group received the same volume of normal saline. The general state and body weight of mice in each group were observed every day, and the morphological changes of Candida albicans in the vaginal lavage of mice were examined by Gram staining. The fungal load in the vaginal lavage of mice was detected by microdilution assay. After the mice were killed, the degree of neutrophil infiltration in the vaginal lavage was detected by Papanicolaou staining. The content of inflammatory cytokines interleukin(IL)-1β, IL-18, and lactate dehydrogenase(LDH) in the vaginal lavage was tested by enzyme-linked immunosorbent assay(ELISA), and vaginal histopathology was analyzed by hematoxylin-eosin(HE) staining. The expression and distribution of NLRP3, PKCδ, pNLRC4, and IL-1Ra in vaginal tissues were measured by immunohistochemistry(IHC), and the expression and distribution of pNLRC4 and IL-1Ra in vaginal tissues were detected by immunofluorescence(IF). The protein expression of NLRP3, PKCδ, pNLRC4, and IL-1Ra was detected by Western blot(WB), and the mRNA expression of NLRP3, PKCδ, pNLRC4, and IL-1Ra was detected by qRT-PCR. The results showed that compared with the blank control group, the VVC model group showed redness, edema, and white secretions in the vagina. Compared with the VVC model group, the BAEB groups showed improved general state of VVC mice. As revealed by Gram staining, Papanicolaou staining, microdilution assay, and HE staining, compared with the blank control group, the VVC model group showed a large number of hyphae, neutrophils infiltration, and increased fungal load in the vaginal lavage, destroyed vaginal mucosa, and infiltration of a large number of inflammatory cells. BAEB could reduce the transformation of C. albicans from yeast to hyphae. High-dose BAEB could significantly reduce neutrophil infiltration and fungal load. Low-and medium-dose BAEB could reduce the da-mage to the vaginal tissue, while high-dose BAEB could restore the damaged vaginal tissues to normal levels. ELISA results showed that the content of inflammatory cytokines IL-1β, IL-18, and LDH in the VVC model group significantly increased compared with that in the blank control group, and the content of IL-1β, IL-18 and LDH in the medium-and high-dose BAEB groups was significantly reduced compared with that in the VVC model group. WB and qRT-PCR results showed that compared with the blank control group, the VVC model group showed reduced protein and mRNA expression of PKCδ, pNLRC4, and IL-1Ra in vaginal tissues of mice and increased protein and mRNA expression of NLRP3. Compared with the VVC model group, the medium-and high-dose BAEB groups showed up-regulated protein and mRNA expression of PKCδ, pNLRC4, and IL-1Ra in vaginal tissues and inhibited protein and mRNA expression of NLRP3 in vaginal tissues. This study indicated that the therapeutic effect of BAEB on VVC mice was presumably related to the negative regulation of NLRP3 inflammasome by promoting PKCδ/NLRC4/IL-1Ra axis.
Female ; Animals ; Humans ; Mice ; Candidiasis, Vulvovaginal/drug therapy* ; Inflammasomes/genetics* ; Interleukin-18 ; NLR Family, Pyrin Domain-Containing 3 Protein/genetics* ; 1-Butanol/pharmacology* ; Fluconazole/therapeutic use* ; Interleukin 1 Receptor Antagonist Protein/therapeutic use* ; Mice, Inbred C57BL ; Candida albicans ; Cytokines ; Drugs, Chinese Herbal/pharmacology* ; Ethanol ; RNA, Messenger ; Calcium-Binding Proteins/therapeutic use*

Background: Thalassemia is a common inherited hemolytic disorder characterized by the absence or reduction of one of the globin chains. Beta thalassemia major generally has oral cavity manifestations. Patients with beta thalassemia major often require routine blood transfusion. However, this treatment has the side effect of accumulating iron in the salivary glands, which increase the risk of dental caries, gingivitis, and secondary infection from Candida albicans. Objective: The aim of this review is to explain the relationship of salivary iron levels and the effects of iron accumulation on dental caries, gingivitis, and Candida albicans infection. Methods: A comprehensive search was performed on PubMed, Scopus, and Google Scholar databases using the keywords beta thalassemia major, iron, dental caries, gingivitis, Candida albicans. Results: Iron is an essential micronutrient needed by Candida albicans for its growth and virulence. Blood transfusion in patients with beta thalassemia major can lead to a buildup of iron in the salivary glands and trigger the formation of non-transferrin bound iron (NTBI). NTBI can circulate in plasma and form a reactive oxygen species (ROS) that stimulate the formation of biofilms and increase dental caries. ROS may affect several genes associated with the inflammatory process and increase the incidence of gingivitis. It can also reduce salivary secretion in patients with thalassemia-β major that cause dysbiosis, which triggers an overgrowth of Candida albicans. Conclusion The excess iron in patients with beta thalassemia major increase the risk of dental caries, gingivitis, and Candida albicans infection.
beta thalassemia major ; iron ; dental caries ; gingivitis ; Candida albicans

Paris rugosa(Melanthiaceae) only grows in Yunnan province of China at present, and its chemical constituents have not been systematically studied. In this study, nine compounds, including one new compound pariposide G(1) and eight known compounds of cerin(2), stigmast-4-en-3-one(3), β-ecdysone(4), ophiopogonin C'(5), methyl protogracillin(6), gracillin(7), parissaponin H(8), and parisyunnanoside G(9), were isolated and identified from the ethanol extract of P. rugosa rhizomes by column chromatography methods and semi-preparative high-performance liquid chromatography(HPLC). Compounds 1-9 were isolated from this plant for the first time. The antibacterial and antifungal activities of all the compounds were evaluated. The results showed that ophiopogonin C' had strong inhibitory effects on Candida albicans [MIC_(90)=(4.68±0.01) μmol·L~(-1)] and the fluconazole-resistant strain of C. albicans [MIC_(90)=(4.66±0.02) μmol·L~(-1)].
Anti-Bacterial Agents ; Candida albicans ; China ; Liliaceae ; Melanthiaceae ; Rhizome

OBJECTIVE: To investigate the distribution and antimicrobial susceptibility of causative microorganisms recovered from patients with intra-abdominal infections (IAIs). METHODS: A total of 2,926 bacterial and fungal strains were identified in samples collected from 1,679 patients with IAIs at the Peking Union Medical College Hospital between 2011 and 2021. Pathogenic bacteria and fungi were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Antimicrobial susceptibility testing (AST) was performed using the VITEK 2 compact system and the Kirby-Bauer method. AST results were interpreted based on the M100-Ed31 clinical breakpoints of the Clinical and Laboratory Standards Institute. RESULTS: Of the 2,926 strains identified, 49.2%, 40.8%, and 9.5% were gram-negative bacteria, gram-positive bacteria, and fungi, respectively. Escherichia coli was the most prevalent pathogen in intensive care unit (ICU) and non-ICU patients; however, a significant decrease was observed in the isolation of E. coli between 2011 and 2021. Specifically, significant decreases were observed between 2011 and 2021 in the levels of extended-spectrum β-lactamase (ESBL)-producing E. coli (from 76.9% to 14.3%) and Klebsiella pneumoniae (from 45.8% to 4.8%). Polymicrobial infections, particularly those involving co-infection with gram-positive and gram-negative bacteria, were commonly observed in IAI patients. Moreover, Candida albicans was more commonly isolated from hospital-associated IAI samples, while Staphylococcus epidermidis had a higher ratio in community-associated IAIs. Additionally, AST results revealed that most antimicrobial agents performed better in non-ESBL-producers than in ESBL-producers, while the overall resistance rates (56.9%-76.8%) of Acinetobacter baumanmii were higher against all antimicrobial agents than those of other common gram-negative bacteria. Indeed, Enterococcus faecium, Enterococcus faecalis, S. epidermidis, and S. aureus were consistently found to be susceptible to vancomycin, teicoplanin, and linezolid. Similarly, C. albicans exhibited high susceptibility to all the tested antifungal drugs. CONCLUSION The distribution and antimicrobial susceptibility of the causative microorganisms from patients with IAIs were altered between 2011 and 2021. This finding is valuable for the implementation of evidence-based antimicrobial therapy and provides guidance for the control of hospital infections.
Humans ; Anti-Bacterial Agents ; Escherichia coli ; Gram-Negative Bacteria ; Gram-Positive Bacteria ; Retrospective Studies ; Staphylococcus aureus ; Intraabdominal Infections/epidemiology* ; Candida albicans ; Coinfection

Candida albicans is the most abundant fungal species in oral cavity. As a smart opportunistic pathogen, it increases the virulence by switching its forms from yeasts to hyphae and becomes the major pathogenic agent for oral candidiasis. However, the overuse of current clinical antifungals and lack of new types of drugs highlight the challenges in the antifungal treatments because of the drug resistance and side effects. Anti-virulence strategy is proved as a practical way to develop new types of anti-infective drugs. Here, seven artemisinins, including artemisinin, dihydroartemisinin, artemisinic acid, dihydroartemisinic acid, artesunate, artemether and arteether, were employed to target at the hyphal development, the most important virulence factor of C. albicans. Artemisinins failed to affect the growth, but significantly inhibited the hyphal development of C. albicans, including the clinical azole resistant isolates, and reduced their damage to oral epithelial cells, while arteether showed the strongest activities. The transcriptome suggested that arteether could affect the energy metabolism of C. albicans. Seven artemisinins were then proved to significantly inhibit the productions of ATP and cAMP, while reduced the hyphal inhibition on RAS1 overexpression strain indicating that artemisinins regulated the Ras1-cAMP-Efg1 pathway to inhibit the hyphal development. Importantly, arteether significantly inhibited the fungal burden and infections with no systemic toxicity in the murine oropharyngeal candidiasis models in vivo caused by both fluconazole sensitive and resistant strains. Our results for the first time indicated that artemisinins can be potential antifungal compounds against C. albicans infections by targeting at its hyphal development.
Animals ; Mice ; Candida albicans ; Candidiasis, Oral/drug therapy* ; Antifungal Agents/pharmacology* ; Hyphae ; Artemisinins/pharmacology*

Humans ; Candida albicans/genetics* ; CARD Signaling Adaptor Proteins/genetics* ; Mutation ; Encephalomyelitis

This study aims to explore the effect of butyl alcohol extract of Baitouweng Decoction(BAEB) on vulvovaginal candidiasis(VVC) in mice and to clarify the mechanism from Toll-like receptors(TLRs)/MyD88 and Dectin-1/Syk signal pathways and NLRP3 inflammasome. To be specific, female KM mice were randomized into control group(i.g., normal saline), model group, fluco-nazole group(i.g., 20 mg·kg~(-1)), and low-dose, medium-dose, and high-dose BAEB groups(i.g., 20, 40, and 80 mg·kg~(-1), respectively). VVC was induced in mice except the control group. After the modeling, administration began and lasted 7 days. The ge-neral conditions and body weight of mice were recorded every day. On the 1 st, 3 rd, 7 th, and 14 th after vaginal infection by Candida albicans, the fungal load in the vaginal lavage fluid of the mice was measured with the plate method, and the morphology of C. albicans in vaginal lavage fluid was observed based on Gram staining. After the mice were killed, vaginal tissues were subjected to hematoxylin-eosin(HE) staining and periodic acid-Schiff(PAS) staining for vaginal histopathological analysis. The content of cytokines in vaginal lavage fluid, such as interleukin(IL)-1β, IL-18, tumor necrosis factor-α(TNF-α), IL-6, and S100 a8, was determined by enzyme-linked immunosorbent assay(ELISA), and content of reactive oxygen species(ROS) in vaginal tissues by tissue ROS detection kit. The protein expression of NLRP3, ASC, caspase-1, Dectin-1, Syk, MyD88, TLR2, TLR4, and nuclear factor-κB(NF-κB) in vaginal tissues was detected by Western blot, and the levels and distribution of NLRP3, Dectin-1, Syk, MyD88, TLR2, and TLR4 in vaginal tissues were determined with the immunohistochemical method. The results show that BAEB can improve the general conditions of VVC mice, reduce the fungal load and C. albicans hyphae in vaginal secretion, decrease ROS content in vaginal tissues and content of cytokines in vaginal lavage fluid, and down-regulate the expression of NLRP3, ASC, caspase-1, Dectin-1, Syk, MyD88, TLR2, TLR4, and NF-κB in vaginal tissues. The above results indicate that BAEB exerts therapeutic effect on VVC mice by down-regulating the key proteins in the TLRs/MyD88 and Dectin-1/Syk signal pathways and NLRP3 inflammasome.
1-Butanol/therapeutic use* ; Animals ; Candida albicans ; Candidiasis, Vulvovaginal/drug therapy* ; Caspase 1/metabolism* ; Cytokines/metabolism* ; Female ; Humans ; Inflammasomes/metabolism* ; Mice ; Myeloid Differentiation Factor 88/metabolism* ; NF-kappa B/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Plant Extracts/therapeutic use* ; Reactive Oxygen Species/metabolism* ; Signal Transduction ; Toll-Like Receptor 2/metabolism* ; Toll-Like Receptor 4/metabolism* ; Tumor Necrosis Factor-alpha/metabolism*

This study explored the mechanism of Sanhuang Decoction(SHD) in treating dextran sulfate sodium(DSS)-induced ulcerative colitis(UC) in mice with Candida albicans(Ca) colonization via high-throughput transcriptome sequencing. Specifically, the animal model was established by oral administration of 3.0% DSS for 7 days followed by intragastrical administration of Ca suspension at 1.0 × 10~8 cells for 4 days and then the mice were treated with SHD enema for 7 days. Afterwards, the general signs were observed and the disease activity index(DAI) was recorded every day. After mice were sacrificed, colon length and colon mucosa damage index(CMDI) were determined and the histomorphology was observed with the HE staining method. The fungal loads of feces were detected with the plate method. Anti-saccharomyces cerevisiae antibody(ASCA) and β-1,3-glucan in serum, and TNF-α, IL-1β, and IL-6 in serum and colon were detected by ELISA. High-throughput RNA sequencing method was adopted to identify transcriptome of colon tissues from the control, model and SHD(15.0 g·kg~(-1)) groups. Differentially expressed genes(DEGs) among groups were screened and the GO and KEGG pathway enrichment analysis of the DEGs was performed. The expression levels of NLRP3, ASC, caspase-1, and IL-1β genes related to the NOD-like receptor signaling pathway which involved 9 DEGs, were examined by qRT-PCR and Western blot. The results demonstrated that SHD improved the general signs, decreased DAI and Ca loads of feaces, alleviated colon edema, erosion, and shortening, and lowered the content of β-1,3-glucan in serum and TNF-α, IL-1β, and IL-6 in serum and colon tissues of mice. Transcriptome sequencing revealed 383 DEGs between SHD and model groups, which were mainly involved in the biological processes of immune system, response to bacterium, and innate immune response. They were mainly enriched in the NOD-like signaling pathway, cytokine-cytokine interaction pathway, and retinol metabolism pathway. Moreover, SHD down-regulated the mRNA and protein levels of NLRP3, caspase-1, and IL-1β. In a word, SHD ameliorates DSS-induced UC in mice colonized with Ca, which probably relates to its regulation of NOD-like receptor signaling pathway.
Animals ; Candida albicans/genetics* ; Colitis, Ulcerative/genetics* ; Colon ; Dextran Sulfate/toxicity* ; Disease Models, Animal ; Drugs, Chinese Herbal ; High-Throughput Nucleotide Sequencing ; Mice ; Transcriptome

Aims: The effect of Quercus infectoria (QI) gall extract on the fungal expression of antioxidant defense enzymes of Candida albicans was studied in an effort to unravel its anti-fungal mechanism. Methodology and results: Minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC), and time kill assays were conducted to analyse the antifungal activity of the extract against C. albicans. Total protein profiles of C. albicans were determined by SDS-PAGE and real-time PCR was used to quantify the genes expression level of superoxide dismutase (SOD1), catalase (CAT1) and glutathione peroxidase (GPX3) following treatment with aqueous QI gall extract. The MIC and MFC values of the extract against C. albicans were 8 mg/mL and 16 mg/mL respectively. Fungistatic and fungicidal activities of the extract were observed after 24 h at 1× MIC and 2× MIC from the time-kill assay. A lower total protein bands density of extract-treated C. albicans was visualized when compared to the untreated cells at concentrations of 1× MIC and 2× MIC. A significant reduction in the expression of GPX3 (p 0.05). Conclusion, significance and impact of study In conclusion, QI gall extract exerted an anti-Candida activity and it is apparently effective in downregulating the gene expression of GPX3 in C. albicans. Of note, the present findings elucidated a preliminary mechanism associated with the organism’s survival resilience which represents a key target for the development of anti-Candida agents in future.
Quercus ; Candida albicans