Augmenting the Activity of Chlorhexidine for Decolonization of Candida auris from Porcine skin

Candida auris readily colonizes skin and efficiently spreads among patients in healthcare settings worldwide. Given the capacity of this drug-resistant fungal pathogen to cause invasive disease with high mortality, hospitals frequently employ chlorhexidine bathing to reduce skin colonization. Using an ex vivo skin model, we show only a mild reduction in C. auris following chlorhexidine application. This finding helps explain why chlorhexidine bathing may have failures clinically, despite potent in vitro activity. We further show that isopropanol augments the activity of chlorhexidine against C. auris on skin. Additionally, we find both tea tree (Melaleuca alternifolia) oil and lemongrass (Cymbopogon flexuosus) oil to further enhance the activity of chlorhexidine/isopropanol for decolonization. We link this antifungal activity to individual oil components and show how some of these components act synergistically with chlorhexidine/isopropanol. Together, the studies provide strategies to improve C. auris skin decolonization through the incorporation of commonly used topical compounds.

Download Full-text

Comparative Evaluations of the Pathogenesis of Candida auris Phenotypes and Candida albicans Using Clinically Relevant Murine Models of Infections

mSphere ◽

10.1128/msphere.00760-20 ◽

2020 ◽

Vol 5 (4) ◽

Author(s):

Taissa Vila ◽

Daniel Montelongo-Jauregui ◽

Hussian Ahmed ◽

Taanya Puthran ◽

Ahmed S. Sultan ◽

...

Keyword(s):

Ex Vivo ◽

Invasive Disease ◽

Health Care Facilities ◽

Murine Models ◽

Candida Auris ◽

Pathogenic Potential ◽

Content Type ◽

Oral Tissue ◽

High Level

ABSTRACT The newly emerged Candida species Candida auris is associated with an exponential rise in life-threatening invasive disease in health care facilities worldwide. Unlike other species, C. auris exhibits a high level of transmissibility, multidrug resistance, and persistence in the environment, yet little is known about its pathogenesis largely due to limited data from animal models. Based on in vitro biofilm evaluations and confocal laser scanning microscopy, C. auris phenotypes with different biofilm-forming abilities were identified, indicating potential clinical implications. Using clinically relevant murine models of implanted catheter, oral, and intraperitoneal infections, we comparatively evaluated the host site-specific pathogenic potential of C. auris phenotypes and Candida albicans. Based on the results of microbial recovery and scanning electron microscopy analysis of explanted catheters, compared to C. albicans, C. auris more avidly adhered and formed biofilms on catheters. However, although C. auris adhered to oral tissue ex vivo, unlike C. albicans, it failed to colonize the oral cavity in vivo, as demonstrated by microbial recovery and tissue histopathology analysis. In contrast, recovery from peritoneal lavage fluid and kidneys during time course experiments demonstrated that C. auris persisted longer in the peritoneal cavity and kidneys. Although there were clear niche-specific differences in pathogenic features between C. auris and C. albicans, no significant differences were noted between the C. auris phenotypes in vivo. The combined findings highlight unique niche-specific pathogenic traits for C. auris warranting further investigations. Understanding the factors contributing to the rise of C. auris as a nosocomial pathogen is critical for controlling the spread of this species. IMPORTANCE The newly emerged Candida species C. auris has been associated with an exponential rise in invasive disease in health care facilities worldwide with a mortality rate approaching 60%. C. auris exhibits a high level of transmissibility, multidrug resistance, and persistence in hospital environments, yet little is known about its pathogenesis largely due to limited data from animal studies. We used clinically relevant murine models of infection to comparatively evaluate the host niche-specific pathogenic potential of C. auris and C. albicans. Findings demonstrated that C. auris adheres more avidly, forming robust biofilms on catheters implanted in mice. However, although C. auris adhered to oral tissue ex vivo, it failed to colonize the oral cavity in vivo. In contrast, in the intraperitoneal infection model, C. auris persisted longer in the peritoneal cavity and kidneys. Understanding the host-pathogen factors contributing to the rise of C. auris as a nosocomial pathogen is critical for controlling the spread of this species.

Download Full-text

Preliminary Assessment of the Mucosal Toxicity of Tea Tree (Melaleuca alternifolia) and Rosemary (Rosmarinus officinalis) Essential Oils on Novel Porcine Uterus Models

International Journal of Molecular Sciences ◽

10.3390/ijms21093350 ◽

2020 ◽

Vol 21 (9) ◽

pp. 3350 ◽

Cited By ~ 1

Author(s):

Martina Bertocchi ◽

Antonella Rigillo ◽

Alberto Elmi ◽

Domenico Ventrella ◽

Camilla Aniballi ◽

...

Keyword(s):

Essential Oils ◽

Ex Vivo ◽

Rosmarinus Officinalis ◽

Future Perspective ◽

Melaleuca Alternifolia ◽

Ex Vivo Model ◽

Tea Tree ◽

Uterine Mucosa ◽

Vitro Model

Antimicrobial resistance, an ever-growing global crisis, is strongly linked to the swine production industry. In previous studies, Melaleuca alternifolia and Rosmarinus officinalis essential oils have been evaluated for toxicity on porcine spermatozoa and for antimicrobial capabilities in artificial insemination doses, with the future perspective of their use as antibiotic alternatives. The aim of the present research was to develop and validate in vitro and ex vivo models of porcine uterine mucosa for the evaluation of mucosal toxicity of essential oils. The in vitro model assessed the toxicity of a wider range of concentrations of both essential oils (from 0.2 to 500 mg/mL) on sections of uterine tissue, while the ex vivo model was achieved by filling the uterine horns. The damage induced by the oils was assessed by Evans Blue (EB) permeability assay and histologically. The expression of ZO-1, a protein involved in the composition of tight junctions, was assessed through immunohistochemical and immunofluorescence analysis. The results showed that low concentrations (0.2–0.4 mg/mL) of both essential oils, already identified as non-spermicidal but still antimicrobial, did not alter the structure and permeability of the swine uterine mucosa. Overall, these findings strengthen the hypothesis of a safe use of essential oils in inseminating doses of boar to replace antibiotics.

Download Full-text

A novel polymer-coated nanoparticle (NP) for urothelium penetration and drug delivery.

Journal of Clinical Oncology ◽

10.1200/jco.2013.31.15_suppl.e15543 ◽

2013 ◽

Vol 31 (15_suppl) ◽

pp. e15543-e15543

Author(s):

Christopher J. Hoimes ◽

Darryl T Martin ◽

Hristos K Kaimakliotis ◽

Christopher J Cheng ◽

William Kevin Kelly ◽

...

Keyword(s):

Drug Delivery ◽

Tumor Regression ◽

Ex Vivo ◽

Fluorescent Microscopy ◽

Invasive Disease ◽

Biodegradable Poly ◽

Migration Pathways ◽

Human Ureter

e15543 Background: Up to 40% of patients with non-invasive bladder cancer (BC) will develop invasive disease progression despite locally-directed therapy. Overcoming the urothelial barrier is a challenge for intravesical drug delivery. We designed a biodegradable poly(lactide-co-glycolide) (PLGA) NP coated with a novel cell penetrating polymer, poly (guanidinium oxanorbornene) (PGON) for testing against BC in vitro and in vivo. We chose to deliver the HDAC inhibitor belinostat (bel) for its BC cell cytotoxicity and inhibition of invasion & migration pathways; key mechanisms that enable progression of BC. Methods: Fluorophore (C6) or bel was encapsulated in PLGA using an oil/water nanoemulsion method, and surface coated with PGON, and then characterized for morphology, size, and loading. BC cell lines UM-UC-3 and T24 were treated with belinostat or NP-bel-PGON vs controls for assessment of cytotoxicity and acetyl-H4 histone expression over time. In vivo murine bladder and ex vivo human ureter were treated with NP-C6-PGON, and compared to NPs coated with chitosan or PEG for urothelial penetration using FACS analysis, tissue extraction, and fluorescence microscopy. UM-UC-3 murine flank xenografts were treated locally biweekly with NP-bel-PGON or controls and assessed for tumor size and acetyl-H4 expression. Results: C6 extraction of intravesically treated mouse bladder and ex-vivo human ureter showed uptake improved ten-fold in NP-C6-PGON compared to other NPs and corroborated by fluorescent microscopy. In vitro, NP-bel-PGON and bel had similar IC50 of ~2.0 μM in UM-UC-3 & T24 lines, and no effect from PGON. Significantly, the NP-bel-PGON treated groups retained 30% of max H4 hyperacetylation whereas bel groups declined to basal at 12hr post wash, which supports a mechanism of intracellular NP release and activity. In vivo, xenografts treated with NP-bel-PGON showed tumor volume reduced 70% and had 2.5 fold higher intratumoral acetyl-H4 expression compared to vehicle three days post final treatment. Conclusions: NP-bel-PGON penetrates the urothelium, is taken up by BC cells, sustains HDAC inhibition, and causes tumor regression. These data demonstrate the potential for NP-bel-PGON as an intravesical nanotherapy of BC.

Download Full-text

Novel Models of Streptococcus canis Colonization and Disease Reveal Modest Contributions of M-Like (SCM) Protein

Microorganisms ◽

10.3390/microorganisms9010183 ◽

2021 ◽

Vol 9 (1) ◽

pp. 183

Author(s):

Ingrid Cornax ◽

Jacob Zulk ◽

Joshua Olson ◽

Marcus Fulde ◽

Victor Nizet ◽

...

Keyword(s):

Ex Vivo ◽

Invasive Disease ◽

Blood Component ◽

Potential Contribution ◽

Murine Models ◽

Vaginal Colonization ◽

Animal Populations ◽

Streptococcus Canis

Streptococcus canis is a common colonizing bacterium of the urogenital tract of cats and dogs that can also cause invasive disease in these animal populations and in humans. Although the virulence mechanisms of S. canis are not well-characterized, an M-like protein, SCM, has recently identified been as a potential virulence factor. SCM is a surface-associated protein that binds to host plasminogen and IgGs suggesting its possible importance in host-pathogen interactions. In this study, we developed in vitro and ex vivo blood component models and murine models of S. canis vaginal colonization, systemic infection, and dermal infection to compare the virulence potential of the zoonotic S. canis vaginal isolate G361 and its isogenic SCM-deficient mutant (G361∆scm). We found that while S. canis establishes vaginal colonization and causes invasive disease in vivo, the contribution of the SCM protein to virulence phenotypes in these models is modest. We conclude that SCM is dispensable for invasive disease in murine models and for resistance to human blood components ex vivo, but may contribute to mucosal persistence, highlighting a potential contribution to the recently appreciated genetic diversity of SCM across strains and hosts.

Download Full-text

In vitro and ex vivo activity of Melaleuca alternifolia against protoscoleces of Echinococcus ortleppi

Parasitology ◽

10.1017/s0031182016001621 ◽

2016 ◽

Vol 144 (2) ◽

pp. 214-219 ◽

Cited By ~ 6

Author(s):

DANIELI URACH MONTEIRO ◽

MARIA ISABEL AZEVEDO ◽

CARLA WEIBLEN ◽

SÔNIA DE AVILA BOTTON ◽

NADINE LYSYK FUNK ◽

...

Keyword(s):

Cystic Echinococcosis ◽

Ex Vivo ◽

Treatment Success ◽

Diagnosis And Treatment ◽

Tea Tree Oil ◽

Hydatid Cysts ◽

Melaleuca Alternifolia ◽

Tea Tree ◽

Difficult Diagnosis

SUMMARYCystic echinococcosis is a zoonotic disease of difficult diagnosis and treatment. The use of protoscolicidal agents in procedures is of utmost importance for treatment success. This study was aimed at analysing the in vitro and ex vivo activity of Melaleuca alternifolia oil (tea tree oil – TTO), its nanoemulsion formulation (NE-TTO) and its major component (terpinen-4-ol) against Echinococcus ortleppi protoscoleces obtained from cattle. Concentrations of 2·5, 5 and 10 mg mL−1 of TTO, 10 mg mL−1 of NE-TTO and 1, 1·5 and 2 mg mL−1 of terpinen-4-ol were evaluated in vitro against protoscoleces at 5, 10, 15 and 30 min. TTO was also injected directly into hydatid cysts (ex vivo analysis, n = 20) and the viability of protoscoleces was evaluated at 5, 15 and 30 min. The results indicated protoscolicidal effect at all tested formulations and concentrations. Terpinen-4-ol (2 mg mL−1) activity was superior when compared with the highest concentration of TTO. NE-TTO reached a gradual protoscolicidal effect. TTO at 20 mg mL−1 showed 90% protoscolicidal action in hydatid cysts at 5 min. The results showed that TTO affects the viability of E. ortleppi protoscoleces, suggesting a new protoscolicidal option to the treatment of cystic equinococcosis.

Download Full-text

Effects of the Tibetan herbal preparation PADMA 28 on blood lipids and lipid oxidisability in subjects with mild hypercholesterolaemia

VASA ◽

10.1024/0301-1526.34.1.11 ◽

2005 ◽

Vol 34 (1) ◽

pp. 11-17 ◽

Cited By ~ 12

Author(s):

Brunner-La Rocca ◽

Schindler ◽

Schlumpf ◽

Saller ◽

Suter

Keyword(s):

Endothelial Dysfunction ◽

Blood Lipids ◽

Ex Vivo ◽

Hdl Cholesterol ◽

Blood Lipid ◽

Tibetan Medicine ◽

Double Blind ◽

Intraarterial Infusion ◽

Padma 28

Background: Previous studies showed an anti-atherosclerotic effect of PADMA 28, an herbal formula based on Tibetan medicine. As the mechanisms of action are not fully understood, we investigated whether PADMA 28 may lower blood lipids and lipid oxidisability, and affect early endothelial dysfunction. Patients and methods: Sixty otherwise healthy subjects with total cholesterol ≥5.2 mmol/l and < 8.0 mmol/l were randomly assigned to placebo or PADMA 28, 3 x 2 capsules daily, for 4 weeks (double-blind). Blood lipids (total, LDL-, and HDL-cholesterol, triglycerides, Apo-lipoprotein A1 and B) and ex vivo lipid oxidisability were measured before and after treatment. In a subset of 24 subjects, endothelial function was assessed using venous occlusion plethysmography with intraarterial infusion of acetylcholine. Isolated LDL and plasma both untreated and pre-treated with PADMA 28 extract were oxidised by the radical generator AAPH. Conjugated diene formation was measured at 245 nm. Results: Blood lipids did not change during the study in both groups. In contrast to previous reports in mild hypercholesterolaemia, no endothelial dysfunction was seen and, consequently, was not influenced by therapy. Ex vivo blood lipid oxidisability was significantly reduced with PADMA 28 (area under curve: 5.29 ± 1.62 to 4.99 ± 1.46, p = 0.01), and remained unchanged in the placebo group (5.33 ± 1.88 to 5.18 ± 1.78, p > 0.1). This effect persisted one week after cessation of medication. In vitro experiments confirmed the prevention of lipid peroxidation in the presence of PADMA 28 extracts. Persistent protection was also seen for LDL isolated from PADMA 28-pretreated blood after being subjected to rigorous purification. Conclusions: This study suggests that the inhibition of blood lipid oxidisability by PADMA 28 may play a role in its anti-atherosclerotic effect.

Download Full-text

The Role of Polyphenols in the Modulation of Plasma Non-Enzymatic Antioxidant Capacity (NEAC)

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000116 ◽

2012 ◽

Vol 82 (3) ◽

pp. 228-232 ◽

Cited By ~ 7

Author(s):

Mauro Serafini ◽

Giuseppa Morabito

Keyword(s):

Antioxidant Capacity ◽

Dietary Intervention ◽

Ex Vivo ◽

The Body ◽

Dietary Polyphenols ◽

Enzymatic Antioxidant ◽

Endogenous Antioxidant

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.

Download Full-text