[Butyl alcohol extract of Baitouweng Decoction alleviates vulvovaginal candidiasis in mice by downregulating NLRP3 inflammasome and related signal pathways].

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)-1ß, 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.

[Main components in butyl alcohol extract of Baitouweng Decoction inhibited neutrophil chemotaxis].

The present study aims to investigate the effects of the main components(aesculin, berberine hydrochloride, and anemoside B4) in the butyl alcohol extract of Baitouweng Decoction(BAEB) on the chemotaxis of neutrophils induced by dimethyl sulfoxide(DMSO). HL60 cells were cultivated in RPMI-1640 complete medium, and transferred into a 6-well plate(2 × 10~5 per mL) with 4 mL in each well, followed by incubation with DMSO at 1.3% for five days. The morphologic changes of cells were observed under an inverted microscope. The CD11 b expression after DMSO induction was analyzed by flow cytometry. The effects of aesculin, berberine hydrochloride, and anemoside B4 on the cell proliferation and migration were detected by CCK8 assay and Transwell assay, respectively. The effects of the main components on the production and polarization of F-actin protein were also examined by flow cytometry and laser confocal microscopy. PI3 K/Akt signaling pathway was checked by Western blot. As revealed by the results, neutrophil-like HL60 cells were observed after DMSO induction. The CD11 b expression in these cells increased significantly as indicated by the flow cytometry. Additionally, 100 µg·mL~(-1) aesculin, 8 µg·mL~(-1) berberine hydrochloride, and 80 µg·mL~(-1) anemoside B4 were potent in inhibiting the migration of neutrophils and reducing F-actin expression. Berberine hydrochloride was verified to be capable of diminishing phosphorylated PI3 K/Akt protein expression. The findings indicate that aesculin, anemoside B4, and especially berberine hydrochloride in the BAEB can inhibit the chemotaxis of neutrophils, which is possibly achieved by the inhibition of F-actin and PI3 K/Akt signaling pathway.

[Effect of butyl alcohol extract of Baitouweng Decoction on vaginal mucosal neutrophil chemotaxis in vulvovaginal candidiasis mice].

To investigate the effects of butyl alcohol extract of Baitouweng Decoction(BAEB) on neutrophil chemotaxis in vaginal mucosa of mice with vulvovaginal candidiasis(VVC). Seventy-two SPF female Kunming mice were randomly divided into normal control group, model group, fluconazole group, BAEB low-dose group, middle-dose group and high-dose group. Subcutaneous injection of estradiol benzoate was conducted to induce pseudo-estrus, and then 2×10~6 CFU·mL~(-1)of Candida albicans was inoculated into vaginal lumen, followed by drug treatment for 7 days. Gram staining was used to observe the morphological changes of C. albicans in vagina; vaginal fungal load was detected on agar plate. Histological changes of vaginal tissues in mice were observed by HE staining. Lactate dehydrogenase(LDH), interleukin-6(IL-6) and tumor necrosis factor(TNF-α) levels in mouse lavage fluid were detected by enzyme-linked immunosorbent assay(ELISA). Neutrophils in vaginal lavage fluid was observed and counted by using Pap smear. The levels of IL-8 and MIP-2 in vaginal mucosa were detected by ELISA. IL-8 and MIP-2 mRNA levels in vaginal mucosa of mice were detected by qRT-PCR. The results showed that as compared with the normal group, VVC model group had a large number of hyphae and a high level of fungal loadinvagina. The vaginal mucosa was completely destroyed, the number of neutrophils increased, and the protein and mRNA levels of IL-8 and MIP-2 were up-regulated. After BAEB treatment, the hyphae of the treatment group was decreased, the fungal load was decreased, the impaired mucosa showed different degrees of improvement, the inflammatory factors were decreased to varying degrees, and the protein and mRNA levels of chemokine IL-8 and MIP-2 were down-regulated. In conclusion, BAEB may be used to treat VVC by inhibiting vulvovaginal candidiasis via blocking neutrophils recruitment into vagina.

Report: Synergism of sodium bicarbonate and baicalin against clinical Candida albicans isolates via broth microdilution method and checkerboard assay.

Invasive fungal infections caused by Candida albicans constitute a prevalent worldwide health problem. Due to limited antifungal agents available, more efforts have been made towards searching the novel anti-candida drugs with low cytotoxicity. The present study was aimed to investigate the antifungal activities of baicalin and/or sodium bicarbonate (SB) against 29 C. albicans isolates including 27 clinical ones. By using broth microdilution method and checkerboard assay, it was observed that the minimum inhibitory concentrations (MICs) of baicalin and SB alone were > 2048 µg/mL, and those of baicalin and SB in combination decreased 16-32 folds with fractional inhibitory concentration index (FICI) in a range of 0.094-0.375. The results presented the strong synergism between SB and baicalin in 27 clinical C. albicans isolates and provided an alternative choice against C. albicans.

[Inhibitory effects of butyl alcohol extract of Baitouweng decoction on virulence factors of Candida tropicalis].

OBJECTIVE: To investigate the effects of butyl alcohol extract of baitouweng decoction (BAEB) on the fungal cell surface hydrophobicity (CSH), filamentation and biofilm formation of Candida tropicalis. METHOD: Gradual dilution method was used to determine the MIC. XTT assay was applied to determine the SMIC80. Time-Kill assay was employed to draw the Time-Kill curve. The water-hydrocarbon two-phase assay was used to measure the cell surface hydrophobicity. Scanning electron microscopy (SEM) was applied to observe the morphological changes of the biofilm. Confocal laser scanning microscopy (CLSM) was applied to determine the thickness of the biofilm. The quantification real-time PCR (qRT-PCR) was used to detect expression changes of releated genes (UME6, ALST3 and NRG1). result: The MICs of BAEB against C. tropicalis strains are determined as 64-128 mg x L(-1). The SMIC80 s of BAEB against the biofilm of Candida tropicalis strains are determined as 256-512 mg x L(-1). Time-Kill curve results indicate that BAEB has a promise fungicidal effect at 256 and 512 mg x L(-1). SEM results shows that 512 mg x L(-1) BAEB can inhibit the formation of C. tropicalis biofilm on Silicone catheter, and the morphology of biofilm is also affected by BAEB. The thickness of C. tropicalis biofilm is reduced by BAEB according to CLSM results. Furthermore, qRT-PCR results indicate that expression of UME6 and ALST3 are significantly down-regulated by BAEB 256,512 mg x L(-1), and NRG1 is not affected by BAEB. CONCLUSION: BAEB inhibits effectively the CSH, filamentation and biofilm formation of VVC strains of C. tropicalis.

[Effect of Huanglian Jiedu decoction in combination with fluconazole on ergosterol of fluconazole-resistant Candida albicans].

OBJECTIVE: To investigate the effects of ethyl acetate extract of Huanglian Jiedu decoction (EAHD) , alone and in combination with fluconazole (FLZ) on FLZ-resistant Candida albicans. METHOD: The minimum inhibitory concentrations (MIC) and sessile MIC80 (SMIC80) of EAHD and FLZ to FLZ-resistant C. albicans were determined by CLSI M27-A3 microdilution method, and the synergy of EAHD combined with FLZ were examined by the checkerboard microdilution assay. Agar plate-method was adopted to observe the rate of antifungal activity according to time-kill curve. HPLC and qRT-PCR were utilized to evaluate the changes of ergosterol content and expressions of related genes, respectively. RESULT: MICs of EAHD ranged from 156 to 1,250 mg · L(-1), those of FLZ from 256 to above 2,048 mg · L(-1) with FICI approximate 0.066 in combination; SMIC80 of EAHD were higher than 1,250 mg · L(-1), SMIC80 of FLZ were higher than 512 mg · L(-1) and up to above 2,048 mg · L(-1). Combination group also showed synergy effect except one group showing addition effect. The results of T-K experiment also confirmed obviously fungicidal effect when treated for 12 h. When compared with control groups, the ergosterol was reduced 85% and 50% in the treatments of combination and EAHD alone by HPLC, respective- ly. The expressions of ERG1, ERG2, ERG6, ERG7 and ERG11 were upregulated, and ACS1, ACS2, MET6 were downregulated when exposed to FLZ. The expressions of the above genes were downregulated by treatment of EAHD. The expressions of ERG2, ERG6, ERG11 were upregulated, while ERG1, ERG7, ACS1, ACS2, MET6 were downregulated in combination group. CONCLUSION: The combination of EAHD and FLZ exhibited synergy against FLZ-resistant C. albicans through decreasing the synthesis of ergosterol, and resulting in the breakage of cell membrane.

[Inhibitory effects of butyl alcohol extract of Baitouweng decoction on yeast-to-hyphae transition of Candida albicans isolates from VVC in alkaline pH environment].

OBJECTIVE: To investigate the effects of butyl alcohol extract of Baitouweng decoction ( BAEB) on yeast-to-hyphae transition of Candida albicans isolates from vulvovaginal candidiasis (VVC) in alkaline pH. METHOD: Serial 2-fold dilution assay was used to determine the minimal inhibitory concentrations (MICs) of Baitouweng decoction extracts against C. albicans isolates from VVC, XTT assay was applied to determine the metabolic activity of C. albicans hypha treated by BAEB for 6 h. The morphological change of C. albicans treated by BAEB was inspected at different pH by inverted microscope, fluorescence microscope, scanning electron microscopy (SEM). Solid agar plate and semi-solid agar were utilized to evaluate colony morphology and invasive growth of C. albicans, respectively. Quantitative Real-time PCR (qRT-PCR) was adopted to observe the expressions of hyphae-specific genes including HWP1, ALS3, CSH1, SUN41 and CaPDE2. RESULT: The MIC of BAEB against C. albicans is less than that of other extracts; hyphae grow best at pH 8. 0; 512 mg · L(-1) and 1,024 mg · L(-1) BAEB could inhibit formation of hyphae and influence colony morphology. When treated by 512 mg · L(-1) and 1,024 mg · L(-1) BAEB, the colonies became smooth; while by 0 and 256 mg · L(-1) BAEB, the colonies became wrinkled. In semi-solid agar, the length of hyphae decreased steadily as the concentration of BAEB lowered. The expression of HWP1, ALS3, CSHl, SUN41 were downregulated by 5.12, 4.26, 3.2 and 2.74 folds, and CaPDE2 was upregulated by 2.38 fold. CONCLUSION: BAEB could inhibit yeast-to-hyphae transition of C. albicans isolates from VVC in alkaline pH.

[Effect of andrographolide on quorum sensing and relevant virulence genes of Candida albicans].

OBJECTIVE: To investigate the effect of andrographolide (AG) on quroum sensing (QS) and relevant virulence genes of Candida albicans. METHOD: Gas-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. RESULT: At 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. CONCLUSION: AG could inhibit the farnesol secretion, promote the tyrosol secretion and down-regulate QS-related virulence genes CHK1 and PBS2 expressions.

[Anti-attachment effect of ethyl acetate extract of Huanglian Jiedu decoction on Candida glabrata].

OBJECTIVE: To investigate anti-attachment effect of ethyl acetate extract of Huanglian Jiedu decoction (EAHD) on Candida glabrata. METHOD: Serial 2-fold dilution assay was used to determine the minimum inhibitory concentrations MICs of EAHD to C. glabrata. XTT assay was used to evaluate the effect of EAHD against adhesion of C. glabrata. Inverted microscope, scanning electron microscope (SEM) and fluorescein diacetate (FDA) staining were applied to observe the morphological changes of C. glabrata in adhesion. PCR was adopted to inspect the expression of attachment-related genes such as EPA1, EPA6 and EPA7. RESULT: The MIC of EAHD and fluconazole to C. glabrata were 320 mg · L(-1) and 1 mg · L(-1) respectively. The total cells including budding cells decreased in a dose-dependent manner following EAHD treatment. The expressions of EPA1, EPA6 and EPA7 were downregulated dramatically after EAHD treatment. CONCLUSION: EAHD could effectively inhibit adherence of C. glabrata.

[Effect of andrographolide on Candida albicans biofilm dispersion].

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.

[Effect of andrographolide derivative Yanhuning on in vivo Candida albicans biofilms in rats].

OBJECTIVE: To investigate the effect of andrographolide derivative Yanhuning (YHN) on Candida albicans biofilms in rats. METHOD: The 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. RESULT: The 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. CONCLUSION: YHN could inhibit C. albicans biofilms in rats.