scholarly journals T-2307 Shows Efficacy in a Murine Model of Candida glabrata Infection despite In Vitro Trailing Growth Phenomena

2010 ◽  
Vol 54 (9) ◽  
pp. 3630-3634 ◽  
Author(s):  
Eio Yamada ◽  
Hiroshi Nishikawa ◽  
Nobuhiko Nomura ◽  
Junichi Mitsuyama

ABSTRACT T-2307, a novel arylamidine, has been shown to exhibit broad-spectrum in vitro and in vivo antifungal activities against clinically significant pathogens. In our preliminary studies, Candida glabrata exhibited significant trailing growth (partial inhibition of growth over an extended range of antifungal concentrations) in the presence of T-2307 when it was tested using the Clinical and Laboratory Standards Institute (CLSI) guidelines with 0.2% glucose and 48 h of incubation, making reading of the MIC difficult. In the present study, we attempted to attenuate trailing growth to avoid misreading of the MIC. On the basis of the hypothesis that T-2307 may inhibit the mitochondrial functions of cells, the carbon source or the glucose concentration in the medium was changed. The trailing growth of C. glabrata ATCC 90030 in the presence of T-2307 was attenuated as the concentration of glucose in the medium decreased to 0.1% or lower, and trailing growth was completely inhibited when glycerol was used. A susceptibility test using Alamar blue was performed to facilitate reading of the MIC without changing the composition of the medium and provided a clear MIC endpoint at 24 h. To investigate if T-2307 shows efficacy against trailing isolates in vivo, we evaluated the efficacy of T-2307 in a murine model of disseminated candidiasis caused by C. glabrata. T-2307 at 0.05 mg/kg of body weight/day significantly decreased the viable count in the kidneys compared to that for the control group (P < 0.05). It would be better to test the susceptibility of C. glabrata to T-2307 using modified media or Alamar blue to avoid misreading of the MIC due to the significant trailing growth.

2012 ◽  
Vol 30 (5_suppl) ◽  
pp. 288-288
Author(s):  
Eugene K. Lee ◽  
Jinesh Gerald ◽  
Ashish M. Kamat

288 Background: Intravesical BCG is the gold standard for non-muscle-invasive bladder cancer (NMIBC). However, many patients do not respond to therapy while others relapse and/or progress. As a result, there remains a need for therapies that can enhance the efficacy of BCG. We explore the efficacy of lenalidomide, an immunomodulatory agent used in multiple myeloma and myelodysplastic syndrome, in combination with BCG in vitro and in an in vivo bladder cancer model. Methods: We studied the effects of lenalidomide in combination with BCG induced cytokines in MBT-2 cells using PI-FACS. For in vitro studies, we used 10 and 100 nM of lenalidomide in combination with TNF-a and FasL. We then performed Western blotting for cell cycle and apoptosis regulatory proteins. Subsequently, we tested the efficacy of this combination in an immunocompetent murine model of bladder cancer with MBT-2 cells in C3H mice using the flank injection method. Drug dosages were 30 mg/kg for lenalidomide and 105 CFU of BCG. Tumor growth curves were created for the control, lenalidomide, BCG and combination treatment mice groups. Immunohistochemistry (IHC) was then performed using antibodies against proteins related to cell cycle, apoptosis, angiogenesis and immune response. Results: PI-FACS identified increased DNA fragmentation in the combinations of lenalidomide and TNF-a and FasL compared to control and each agent alone. Using Western blotting, we demonstrated that the combination resulted in apoptosis via caspase-3 activation. In the murine model, combination therapy resulted in a statistically significant decreased tumor size compared to the control group. While the BCG alone and lenalidomide alone groups did show a trend toward smaller tumor, they did not reach statistical significance. Furthermore, the TUNEL assay showed a substantial increase in apoptosis only in the combination group. Immunohistochemistry demonstrated decreased angiogenesis in all treatment groups compared to control, as well as, decreased T-cell infiltration. Conclusions: Our study demonstrates a potential role for the immunomodulatory agent, lenalidomide, in combination with BCG for NMIBC. This in vivo model serves as a template for future clinical trials.


2002 ◽  
Vol 46 (5) ◽  
pp. 1240-1245 ◽  
Author(s):  
Justina Y. Ju ◽  
Cynthia Polhamus ◽  
Kieren A. Marr ◽  
Steven M. Holland ◽  
John E. Bennett

ABSTRACT Candida glabrata is the second leading cause of adult candidemia, resulting in high mortality. Amphotericin B is considered the treatment of choice, while the efficacy of fluconazole is controversial and caspofungin efficacy is unknown. To ascertain drug efficacy in vivo, the utility of a murine model of C. glabrata infection was investigated. C. glabrata was found to cause progressive, lethal infection when injected intravenously into C57BL/6 mice with reduced oxidative microbicidal capacity due to knockout of the p47phox gene. Spleen and kidney organ CFU counts were determined in groups of mice 2 days after the mice completed 6 days of daily intraperitoneal drug treatment, which began on the day of infection. Daily injections of fluconazole at 80 mg/kg did not reduce spleen or kidney CFU counts after infection with C. glabrata strains having in vitro fluconazole MICs of 2, 32, or 256 μg/ml compared to saline-treated controls. However, this fluconazole regimen reduced spleen CFU counts in mice infected with Candida albicans, an infection that is known to be responsive to fluconazole. Caspofungin at 5 mg/kg and amphotericin B at 5 mg/kg were both effective in reducing fungal burden in spleens and kidneys of C. glabrata-infected mice. Ten mice treated for 6 days with caspofungin at 1 mg/kg survived for 15 days, though all 10 saline-injected mice died or were so ill that they had to be sacrificed by 96 h postinfection. This murine model provided evidence of the efficacy of amphotericin B and caspofungin but not of fluconazole against C. glabrata infection.


2011 ◽  
Vol 55 (5) ◽  
pp. 1852-1860 ◽  
Author(s):  
Sélène Ferrari ◽  
Maurizio Sanguinetti ◽  
Flavia De Bernardis ◽  
Riccardo Torelli ◽  
Brunella Posteraro ◽  
...  

ABSTRACTMitochondrial dysfunction is one of the possible mechanisms by which azole resistance can occur inCandida glabrata. Cells with mitochondrial DNA deficiency (so-called “petite mutants”) upregulate ATP binding cassette (ABC) transporter genes and thus display increased resistance to azoles. Isolation of suchC. glabratamutants from patients receiving antifungal therapy or prophylaxis has been rarely reported. In this study, we characterized two sequential and relatedC. glabrataisolates recovered from the same patient undergoing azole therapy. The first isolate (BPY40) was azole susceptible (fluconazole MIC, 4 μg/ml), and the second (BPY41) was azole resistant (fluconazole MIC, >256 μg/ml). BPY41 exhibited mitochondrial dysfunction and upregulation of the ABC transporter genesC. glabrata CDR1(CgCDR1),CgCDR2, andCgSNQ2. We next assessed whether mitochondrial dysfunction conferred a selective advantage during host infection by testing the virulence of BPY40 and BPY41 in mice. Surprisingly, even within vitrogrowth deficiency compared to BPY40, BPY41 was more virulent (as judged by mortality and fungal tissue burden) than BPY40 in both systemic and vaginal murine infection models. The increased virulence of the petite mutant correlated with a drastic gain of fitness in mice compared to that of its parental isolate. To understand this unexpected feature, genome-wide changes in gene expression driven by the petite mutation were analyzed by use of microarrays duringin vitrogrowth. Enrichment of specific biological processes (oxido-reductive metabolism and the stress response) was observed in BPY41, all of which was consistent with mitochondrial dysfunction. Finally, some genes involved in cell wall remodelling were upregulated in BPY41 compared to BPY40, which may partially explain the enhanced virulence of BPY41. In conclusion, this study shows for the first time that mitochondrial dysfunction selectedin vivounder azole therapy, even if strongly affectingin vitrogrowth characteristics, can confer a selective advantage under host conditions, allowing theC. glabratamutant to be more virulent than wild-type isolates.


1990 ◽  
Vol 29 (03) ◽  
pp. 120-124
Author(s):  
R. P. Baum ◽  
E. Rohrbach ◽  
G. Hör ◽  
B. Kornhuber ◽  
E. Busse

The effect of triiodothyronine (T3) on the differentiation of cultured neuroblastoma (NB) cells was studied after 9 days of treatment with a dose of 10-4 M/106 cells per day. Using phase contrast microscopy, 30-50% of NB cells showed formation of neurites as a morphological sign of cellular differentiation. The initial rise of the mitosis rate was followed by a plateau. Changes in cyclic nucleotide content, in the triphosphates and in the activity of the enzyme ornithine decarboxylase (ODC) were assessed in 2 human and 2 murine cell lines to serve as biochemical parameters of the cell differentiation induced by T3. Whereas the cAMP level increased significantly (3 to 7 fold compared with its initial value), the cGMP value dropped to 30 to 50% of that of the control group. ATP and GTP increased about 200%, the ODC showed a decrease of about 50%. The present studies show a biphasic effect of T3 on neuroblastoma cells: the initial rise of mitotic activity is followed by increased cell differentiation starting from day 4 of the treatment.


2020 ◽  
Author(s):  
K. Zerrouki ◽  
N. Djebli ◽  
L. Gadouche ◽  
I. Erdogan Orhan ◽  
F. SezerSenol Deniz ◽  
...  

Nowadays, because of the industrialization, a lot of contaminant were available ; the consequences of this availability are apparition of diseases including neurodegeneration. Neurodegenerative diseases of the human brain comprise a variety of disorders that affect an increasing percentage of the population. This study is based on the effect of the Boswellic resin, which is from a medicinal plant and known for its antioxidant effects on nerve cell damage. The objective of this work was to evaluate the in vitro and in vivo effects of the Boswellic resin on anticholinesterase activity and Alzheimer’s disease (AD) induced by D-galactose and aluminum tetrachloride in Swiss mice. Chemical composition of the resin essential oil was identified by the CG-MS analysis. The antioxidant activity was also assessed by the DMPD and metal chelation methods. In order to understand the mechanism of memory improvement, the acetylcholinesterase, AChE, and butyrylcholinesterase, BChE, inhibitory assays were performed. In vivo part of the study was achieved on Swiss mice divided into four groups: control, AD model, treated AD, and treated control group. The identification of chemical composition by CG-MS reach the 89.67% of the total extract compounds presented some very important molecules (p-Cymene, n-Octyl acetate, α-Pinene…). The present study proves that Boswellic resin improves memory and learning in treated Alzheimer’s group, modulates the oxidative stress and be involved in the protective effect against amyloid deposition and neurodegeneration, and stimulates the immune system in mice’s brain.


2020 ◽  
Vol 318 (1) ◽  
pp. G1-G9 ◽  
Author(s):  
Richard A. Jacobson ◽  
Kiedo Wienholts ◽  
Ashley J. Williamson ◽  
Sara Gaines ◽  
Sanjiv Hyoju ◽  
...  

Perforations, anastomotic leak, and subsequent intra-abdominal sepsis are among the most common and feared complications of invasive interventions in the colon and remaining intestinal tract. During physiological healing, tissue protease activity is finely orchestrated to maintain the strength and integrity of the submucosa collagen layer in the wound. We (Shogan, BD et al. Sci Trans Med 7: 286ra68, 2015.) have previously demonstrated in both mice and humans that the commensal microbe Enterococcus faecalis selectively colonizes wounded colonic tissues and disrupts the healing process by amplifying collagenolytic matrix-metalloprotease activity toward excessive degradation. Here, we demonstrate for the first time, to our knowledge, a novel collagenolytic virulence mechanism by which E. faecalis is able to bind and locally activate the human fibrinolytic protease plasminogen (PLG), a protein present in high concentrations in healing colonic tissue. E. faecalis-mediated PLG activation leads to supraphysiological collagen degradation; in this study, we demonstrate this concept both in vitro and in vivo. This pathoadaptive response can be mitigated with the PLG inhibitor tranexamic acid (TXA) in a fashion that prevents clinically significant complications in validated murine models of both E. faecalis- and Pseudomonas aeruginosa-mediated colonic perforation. TXA has a proven clinical safety record and is Food and Drug Administration approved for topical application in invasive procedures, albeit for the prevention of bleeding rather than infection. As such, the novel pharmacological effect described in this study may be translatable to clinical trials for the prevention of infectious complications in colonic healing. NEW & NOTEWORTHY This paper presents a novel mechanism for virulence in a commensal gut microbe that exploits the human fibrinolytic system and its principle protease, plasminogen. This mechanism is targetable by safe and effective nonantibiotic small molecules for the prevention of infectious complications in the healing gut.


Author(s):  
Joon M. Jung ◽  
Hae K. Yoon ◽  
Chang J. Jung ◽  
Soo Y. Jo ◽  
Sang G. Hwang ◽  
...  

Cold plasma can be beneficial for promoting skin wound healing and has a high potential of being effectively used in treating various wounds. Our aim was to verify the effect of cold plasma in accelerating wound healing and investigate its underlying mechanism in vitro and in vivo. For the in vivo experiments, 2 full-thickness dermal wounds were created in each mouse (n = 30). While one wound was exposed to 2 daily plasma treatments for 3 min, the other wound served as a control. The wounds were evaluated by imaging and histological analyses at 4, 7, and 11 days post the wound infliction process. Immunohistochemical studies were also performed at the same time points. In vitro proliferation and scratch assay using HaCaT keratinocytes and fibroblasts were performed. The expression levels of wound healing–related genes were analyzed by real-time polymerase chain reaction and western blot analysis. On day 7, the wound healing rates were 53.94% and 63.58% for the control group and the plasma-treated group, respectively. On day 11, these rates were 76.05% and 93.44% for the control and plasma-treated groups, respectively, and the difference between them was significant ( P = .039). Histological analysis demonstrated that plasma treatment promotes the formation of epidermal keratin and granular layers. Immunohistochemical studies also revealed that collagen 1, collagen 3, and alpha-smooth muscle actin appeared more abundantly in the plasma-treated group than in the control group. In vitro, the proliferation of keratinocytes was promoted by plasma exposure. Scratch assay showed that fibroblast exposure to plasma increased their migration. The expression levels of collagen 1, collagen 3, and alpha-smooth muscle actin were elevated upon plasma treatment. In conclusion, cold plasma can accelerate skin wound healing and is well tolerated.


2020 ◽  
pp. 155335062097800
Author(s):  
Ian A. Makey ◽  
Nitin A. Das ◽  
Samuel Jacob ◽  
Magdy M. El-Sayed Ahmed ◽  
Colleen M. Makey ◽  
...  

Background. Retained hemothorax (RH) is a common problem in cardiothoracic and trauma surgery. We aimed to determine the optimum agitation technique to enhance thrombus dissolution and drainage and to apply the technique to a porcine-retained hemothorax. Methods. Three agitation techniques were tested: flush irrigation, ultrasound, and vibration. We used the techniques in a benchtop model with tissue plasminogen activator (tPA) and pig hemothorax with tPA. We used the most promising technique vibration in a pig hemothorax without tPA. Statistics. We used 2-sample t tests for each comparison and Cohen d tests to calculate effect size (ES). Results. In the benchtop model, mean drainages in the agitation group and control group and the ES were flush irrigation, 42%, 28%, and 2.91 ( P = .10); ultrasound, 35%, 27%, and .76 ( P = .30); and vibration, 28%, 19%, and 1.14 ( P = .04). In the pig hemothorax with tPA, mean drainages and the ES of each agitation technique compared with control (58%) were flush irrigation, 80% and 1.14 ( P = .37); ultrasound, 80% and 2.11 ( P = .17); and vibration, 95% and 3.98 ( P = .06). In the pig hemothorax model without tPA, mean drainages of the vibration technique and control group were 50% and 43% (ES = .29; P = .65). Discussion. In vitro studies suggested flush irrigation had the greatest effect, whereas only vibration was significantly different vs the respective controls. In vivo with tPA, vibration showed promising but not statistically significant results. Results of in vivo experiments without tPA were negative. Conclusion. Agitation techniques, in combination with tPA, may enhance drainage of hemothorax.


AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Masarra M. Sakr ◽  
Walid F. Elkhatib ◽  
Khaled M. Aboshanab ◽  
Eman M. Mantawy ◽  
Mahmoud A. Yassien ◽  
...  

AbstractFailure in the treatment of P. aeruginosa, due to its broad spectrum of resistance, has been associated with increased patient mortality. One alternative approach for infection control is quorum quenching which was found to decrease virulence of such pathogen. In this study, the efficiency of a recombinant Ahl-1 lactonase formulated as a hydrogel was investigated to control the infection of multidrug resistant (MDR) P. aeruginosa infected burn using a murine model. The recombinant N-acylhomoserine lactonase (Ahl-1) was formulated as a hydrogel. To test its ability to control the infection of MDR P. aeruginosa, a thermal injury model was used. Survival rate, and systemic spread of the infection were evaluated. Histopathological examination of the animal dorsal skin was also done for monitoring the healing and cellular changes at the site of infection. Survival rate in the treated group was 100% relative to 40% in the control group. A decrease of up to 3 logs of bacterial count in the blood samples of the treated animals relative to the control group and a decrease of up to 4 logs and 2.3 logs of bacteria in lung and liver samples, respectively were observed. Histopathological examination revealed more enhanced healing process in the treated group. Accordingly, by promoting healing of infected MDR P. aeruginosa burn and by reducing systemic spread of the infection as well as decreasing mortality rate, Ahl-1 hydrogel application is a promising strategy that can be used to combat and control P. aeruginosa burn infections.


Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1602
Author(s):  
Anna Elizarova ◽  
Alexey Sokolov ◽  
Valeria Kostevich ◽  
Ekaterina Kisseleva ◽  
Evgeny Zelenskiy ◽  
...  

As shown recently, oleic acid (OA) in complex with lactoferrin (LF) causes the death of cancer cells, but no mechanism(s) of that toxicity have been disclosed. In this study, constitutive parameters of the antitumor effect of LF/OA complex were explored. Complex LF/OA was prepared by titrating recombinant human LF with OA. Spectral analysis was used to assess possible structural changes of LF within its complex with OA. Structural features of apo-LF did not change within the complex LF:OA = 1:8, which was toxic for hepatoma 22a cells. Cytotoxicity of the complex LF:OA = 1:8 was tested in cultured hepatoma 22a cells and in fresh erythrocytes. Its anticancer activity was tested in mice carrying hepatoma 22a. In mice injected daily with LF-8OA, the same tumor grew significantly slower. In 20% of animals, the tumors completely resolved. LF alone was less efficient, i.e., the tumor growth index was 0.14 for LF-8OA and 0.63 for LF as compared with 1.0 in the control animals. The results of testing from 48 days after the tumor inoculation showed that the survival rate among LF-8OA-treated animals was 70%, contrary to 0% rate in the control group and among the LF-treated mice. Our data allow us to regard the complex of LF and OA as a promising tool for cancer treatment.


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