scholarly journals Pharmacokinetics and Pharmacodynamics of the Nitroimidazole DNDI-0690 in Mouse Models of Cutaneous Leishmaniasis

2019 ◽  
Vol 63 (9) ◽  
Author(s):  
Gert-Jan Wijnant ◽  
Simon L. Croft ◽  
Raul de la Flor ◽  
Mo Alavijeh ◽  
Vanessa Yardley ◽  
...  
Keyword(s):  
Cutaneous Leishmaniasis ◽  
Mouse Models ◽  
Drug Exposure ◽  
Oral Treatment ◽  
Drug Application ◽  
Skin Tissue ◽  
Drug Candidate ◽  
Topical Formulation ◽  
Content Type

ABSTRACT The nitroimidazole DNDI-0690 is a clinical drug candidate for visceral leishmaniasis (VL) that also shows potent in vitro and in vivo activity against cutaneous leishmaniasis (CL). To support further development of this compound into a patient-friendly oral or topical formulation for the treatment of CL, we investigated the free drug exposure at the dermal site of infection and subsequent elimination of the causative Leishmania pathogen. This study evaluates the pharmacokinetics (PK) and pharmacodynamics (PD) of DNDI-0690 in mouse models of CL. Skin microdialysis and Franz diffusion cell permeation studies revealed that DNDI-0690 permeated poorly (<1%) into the skin lesion upon topical drug application (0.063% [wt/vol], 30 μl). In contrast, a single oral dose of 50 mg/kg of body weight resulted in the rapid and nearly complete distribution of protein-unbound DNDI-0690 from the plasma into the infected dermis (ratio of the area under the curve [0 to 6 h] of the free DNDI-0690 concentration in skin tissue to blood [fAUC0-6 h, skin tissue/fAUC0-6 h, blood] is greater than 80%). Based on in vivo bioluminescence imaging, two doses of 50 mg/kg DNDI-0690 were sufficient to reduce the Leishmania mexicana parasite load by 100-fold, while 6 such doses were needed to achieve similar killing of L. major; this was confirmed by quantitative PCR. The combination of rapid accumulation and potent activity in the Leishmania-infected dermis indicates the potential of DNDI-0690 as a novel oral treatment for CL.

scholarly journals Development of a Novel Formulation with Hypericin To Treat Cutaneous Leishmaniasis Based on Photodynamic Therapy inIn VitroandIn VivoStudies

2015 ◽  
Vol 59 (9) ◽  
pp. 5804-5813 ◽  
Author(s):  
Andrés Montoya ◽  
Alejandro Daza ◽  
Diana Muñoz ◽  
Karina Ríos ◽  
Viviana Taylor ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Cutaneous Leishmaniasis ◽  
Hypericum Perforatum ◽  
Topical Formulation ◽  
Hamster Model ◽  
Content Type ◽  
Intracellular Amastigotes ◽  
Infected Cells

ABSTRACTAn evaluation of the leishmanicidal activityin vitroandin vivoof hypericin, an expanded-spectrum photosensitizer found inHypericum perforatum, is presented. Hypericin was evaluated against intracellular amastigotesin vitroofLeishmania(Viannia)panamensis. A topical formulation containing 0.5% hypericin was developed and assayedin vivoin a hamster model of cutaneous leishmaniasis. Results demonstrate that hypericin induces a significant antiamastigote effectin vitroagainstL. panamensisby decreasing the number of parasites inside infected cells. The topical formulation of 0.5% hypericin allows healing ofL. panamensis-induced lesions upon a topical application of 40 mg/day plus visible-light irradiation (5 J/cm2, 15 min), twice a week for 3 weeks.

scholarly journals Antitrypanosomal Activity of Fexinidazole, a New Oral Nitroimidazole Drug Candidate for Treatment of Sleeping Sickness

2011 ◽  
Vol 55 (12) ◽  
pp. 5602-5608 ◽  
Author(s):  
Marcel Kaiser ◽  
Michael A. Bray ◽  
Monica Cal ◽  
Bernadette Bourdin Trunz ◽  
Els Torreele ◽  
...  
Keyword(s):  
Oral Treatment ◽  
Sleeping Sickness ◽  
Drug Candidate ◽  
Pharmacokinetic Data ◽  
Parent Molecule ◽  
Content Type ◽  
Trypanocidal Activity ◽  
Parasite Strains

ABSTRACTFexinidazole is a 5-nitroimidazole drug currently in clinical development for the treatment of human sleeping sickness (human African trypanosomiasis [HAT]), caused by infection with species of the protozoan parasiteTrypanosoma brucei. The compound and its two principal metabolites, sulfoxide and sulfone, have been assessed for their ability to kill a range ofT. bruceiparasite strainsin vitroand to cure both acute and chronic HAT disease models in the mouse. The parent molecule and both metabolites have shown trypanocidal activityin vitroin the 0.7-to-3.3 μM (0.2-to-0.9 μg/ml) range against all parasite strains tested.In vivo, fexinidazole is orally effective in curing both acute and chronic diseases in the mouse at doses of 100 mg/kg of body weight/day for 4 days and 200 mg/kg/day for 5 days, respectively. Pharmacokinetic data indicate that it is likely that the sulfoxide and sulfone metabolites provide most, if not all, of thein vivokilling activity. Fexinidazole and its metabolites require up to 48 h exposure in order to induce maximal trypanocidal efficacyin vitro. The parent drug and its metabolites show noin vitrocross-reactivity in terms of trypanocidal activity with either themselves or other known trypanocidal drugs in use in humans. Thein vitroandin vivoantitrypanosomal activities of fexinidazole and its two principal metabolites provide evidence that the compound has the potential to be an effective oral treatment for both theT. b. gambienseandT. b. rhodesienseforms of human sleeping sickness and both stages of the disease.

scholarly journals Effective Treatment of Mycobacterium avium subsp. hominissuis and Mycobacterium abscessus Species Infections in Macrophages, Biofilm, and Mice by Using Liposomal Ciprofloxacin

2018 ◽  
Vol 62 (10) ◽  
Author(s):  
James D. Blanchard ◽  
Valerie Elias ◽  
David Cipolla ◽  
Igor Gonda ◽  
Luiz E. Bermudez
Keyword(s):  
Effective Treatment ◽  
Mouse Models ◽  
Mycobacterium Avium ◽  
Nontuberculous Mycobacteria ◽  
Mycobacterium Abscessus ◽  
Content Type ◽  
Number Of Individuals ◽  
Intranasal Instillation

ABSTRACT Nontuberculous mycobacteria (NTM) affect an increasing number of individuals worldwide. Infection with these organisms is more common in patients with chronic lung conditions, and treatment is challenging. Quinolones, such as ciprofloxacin, have been used to treat patients, but the results have not been encouraging. In this report, we evaluate novel formulations of liposome-encapsulated ciprofloxacin (liposomal ciprofloxacin) in vitro and in vivo. Its efficacy against Mycobacterium avium and Mycobacterium abscessus was examined in macrophages, in biofilms, and in vivo using intranasal instillation mouse models. Liposomal ciprofloxacin was significantly more active than free ciprofloxacin against both pathogens in macrophages and biofilms. When evaluated in vivo, treatment with the liposomal ciprofloxacin formulations was associated with significant decreases in the bacterial loads in the lungs of animals infected with M. avium and M. abscessus. In summary, topical delivery of liposomal ciprofloxacin in the lung at concentrations greater than those achieved in the serum can be effective in the treatment of NTM, and further evaluation is warranted.

scholarly journals In VitroandIn VivoActivity of Solithromycin (CEM-101) against Plasmodium Species

2011 ◽  
Vol 56 (2) ◽  
pp. 703-707 ◽  
Author(s):  
Sergio Wittlin ◽  
Eric Ekland ◽  
J Carl Craft ◽  
Julie Lotharius ◽  
Ian Bathurst ◽  
...  
Keyword(s):  
Drug Exposure ◽  
Antimalarial Activity ◽  
Plasmodium Species ◽  
Parasite Clearance ◽  
Response To Treatment ◽  
Cross Resistance ◽  
Asexual Blood Stage ◽  
Content Type

ABSTRACTWith the emergence ofPlasmodium falciparuminfections exhibiting increased parasite clearance times in response to treatment with artemisinin-based combination therapies, the need for new therapeutic agents is urgent. Solithromycin, a potent new fluoroketolide currently in development, has been shown to be an effective, broad-spectrum antimicrobial agent. Malarial parasites possess an unusual organelle, termed the apicoplast, which carries a cryptic genome of prokaryotic origin that encodes its own translation and transcription machinery. Given the similarity of apicoplast and bacterial ribosomes, we have examined solithromycin for antimalarial activity. Other antibiotics known to target the apicoplast, such as the macrolide azithromycin, demonstrate a delayed-death effect, whereby treated asexual blood-stage parasites die in the second generation of drug exposure. Solithromycin demonstrated potentin vitroactivity against the NF54 strain ofP. falciparum, as well as against two multidrug-resistant strains, Dd2 and 7G8. The dramatic increase in potency observed after two generations of exposure suggests that it targets the apicoplast. Solithromycin also retained potency against azithromycin-resistant parasites derived from Dd2 and 7G8, although these lines did demonstrate a degree of cross-resistance. In anin vivomodel ofP. bergheiinfection in mice, solithromycin demonstrated a 100% cure rate when administered as a dosage regimen of four doses of 100 mg/kg of body weight, the same dose required for artesunate or chloroquine to achieve 100% cure rates in this rodent malaria model. These promisingin vitroandin vivodata support further investigations into the development of solithromycin as an antimalarial agent.

scholarly journals Differential Regulation of L-Arginine Metabolism through Arginase 1 during Infection with Leishmania mexicana Isolates Obtained from Patients with Localized and Diffuse Cutaneous Leishmaniasis

2020 ◽  
Vol 88 (7) ◽  
Author(s):  
Arturo A. Wilkins-Rodríguez ◽  
Armando Pérez-Torres ◽  
Alma R. Escalona-Montaño ◽  
Laila Gutiérrez-Kobeh
Keyword(s):  
Cutaneous Leishmaniasis ◽  
Clinical Manifestations ◽  
Differential Regulation ◽  
Leishmania Mexicana ◽  
Arginine Metabolism ◽  
Content Type ◽  
Arginase 1 ◽  
Oxide Synthase ◽  
Inducible Nitric Oxide

ABSTRACT l-Arginine metabolism through arginase 1 (Arg-1) and inducible nitric oxide synthase (NOS2) constitutes a fundamental axis for the resolution or progression of leishmaniasis. Infection with Leishmania mexicana can cause two distinct clinical manifestations: localized cutaneous leishmaniasis (LCL) and diffuse cutaneous leishmaniasis (DCL). In this work, we analyzed in an in vivo model the capacity of two L. mexicana isolates, one obtained from a patient with LCL and the other from a patient with DCL, to regulate the metabolism of l-arginine through Arg-1 and NOS2. Susceptible BALB/c mice were infected with L. mexicana isolates from both clinical manifestations, and the evolution of the infection as well as protein presence and activity of Arg-1 and NOS2 were evaluated. The lesions of mice infected with the DCL isolate were bigger, had higher parasite loads, and showed greater protein presence and enzymatic activity of Arg-1 than the lesions of mice infected with the LCL isolate. In contrast, NOS2 protein synthesis was poorly or not induced in the lesions of mice infected with the LCL or DCL isolate. The immunochemistry analysis of the lesions allowed the identification of highly parasitized macrophages positive for Arg-1, while no staining for NOS2 was found. In addition, we observed in lesions of patients with DCL macrophages with higher parasite loads and stronger Arg-1 staining than those in lesions of patients with LCL. Our results suggest that L. mexicana isolates obtained from patients with LCL or DCL exhibit different virulence or pathogenicity degrees and differentially regulate l-arginine metabolism through Arg-1.

scholarly journals Efficacy of Bacteriophages in a Staphylococcus aureus Nondiabetic or Diabetic Foot Infection Murine Model

2019 ◽  
Vol 64 (2) ◽  
Author(s):  
S. Albac ◽  
M. Medina ◽  
D. Labrousse ◽  
D. Hayez ◽  
D. Bonnot ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Mouse Models ◽  
Murine Model ◽  
Phage Therapy ◽  
Single Injection ◽  
Antibacterial Efficacy ◽  
Content Type ◽  
Diabetic Foot Infection ◽  
Preclinical And Clinical Studies

ABSTRACT This study investigated the in vivo efficacy of three bacteriophages combined compared with linezolid in two mouse models (nondiabetic and diabetic) of Staphylococcus aureus foot infection. In both models, a single injection of bacteriophages in the hindpaw showed significant antibacterial efficacy. Linezolid was as effective as bacteriophages in nondiabetic animals but ineffective in diabetic animals. These findings further support preclinical and clinical studies for the development of phage therapy.

scholarly journals Zinc(II)-Dipicolylamine Coordination Complexes as Targeting and Chemotherapeutic Agents for Leishmania major

2016 ◽  
Vol 60 (5) ◽  
pp. 2932-2940 ◽  
Author(s):  
Douglas R. Rice ◽  
Paola Vacchina ◽  
Brianna Norris-Mullins ◽  
Miguel A. Morales ◽  
Bradley D. Smith
Keyword(s):  
Cutaneous Leishmaniasis ◽  
Mammalian Cells ◽  
Leishmania Major ◽  
Parasite Burden ◽  
Coordination Complexes ◽  
Chemotherapeutic Agents ◽  
Selective Toxicity ◽  
Content Type

ABSTRACTCutaneous leishmaniasis is a neglected tropical disease that causes painful lesions and severe disfigurement. Modern treatment relies on a few chemotherapeutics with serious limitations, and there is a need for more effective alternatives. This study describes the selective targeting of zinc(II)-dipicolylamine (ZnDPA) coordination complexes towardLeishmania major, one of the species responsible for cutaneous leishmaniasis. Fluorescence microscopy ofL. majorpromastigotes treated with a fluorescently labeled ZnDPA probe indicated rapid accumulation of the probe within the axenic promastigote cytosol. The antileishmanial activities of eight ZnDPA complexes were measured using anin vitroassay. All tested complexes exhibited selective toxicity againstL. majoraxenic promastigotes, with 50% effective concentration values in the range of 12.7 to 0.3 μM. Similar toxicity was observed against intracellular amastigotes, but there was almost no effect on the viability of mammalian cells, including mouse peritoneal macrophages.In vivotreatment efficacy studies used fluorescence imaging to noninvasively monitor changes in the red fluorescence produced by an infection of mCherry-L. majorin a mouse model. A ZnDPA treatment regimen reduced the parasite burden nearly as well as the reference care agent, potassium antimony(III) tartrate, and with less necrosis in the local host tissue. The results demonstrate that ZnDPA coordination complexes are a promising new class of antileishmanial agents with potential for clinical translation.

scholarly journals Indole-2-Carboxamides Are Active against Mycobacterium abscessus in a Mouse Model of Acute Infection

2019 ◽  
Vol 63 (3) ◽  
Author(s):  
Amit N. Pandya ◽  
Pavan K. Prathipati ◽  
Pooja Hegde ◽  
Wei Li ◽  
Kyle F. Graham ◽  
...  
Keyword(s):  
Mouse Model ◽  
Oral Administration ◽  
Infected Mouse ◽  
Mouse Models ◽  
Nontuberculous Mycobacteria ◽  
Acute Infection ◽  
Mycobacterium Abscessus ◽  
Content Type ◽  
Efficacy Studies

ABSTRACT Nontuberculous mycobacteria (NTM) pathogens particularly infect patients with structural lung disorders. We previously reported novel indole-2-carboxamides (ICs) that are active against a wide panel of NTM pathogens. This study discloses in vivo data for two lead molecules (compounds 5 and 25) that were advanced for efficacy studies in Mycobacterium abscessus-infected mouse models. Oral administration of the lead molecules showed a statistically significant reduction in the bacterial loads in lung and spleen of M. abscessus-infected mice.

scholarly journals Immunohistochemical Investigations of Treatment with Ro 13-3978, Praziquantel, Oxamniquine, and Mefloquine in Schistosoma mansoni-Infected Mice

2017 ◽  
Vol 61 (12) ◽  
Author(s):  
Gordana Panic ◽  
Marie-Thérèse Ruf ◽  
Jennifer Keiser
Keyword(s):  
T Cells ◽  
B Cells ◽  
Schistosoma Mansoni ◽  
Parasite Clearance ◽  
Drug Candidate ◽  
Minimal Cell ◽  
Onset Of Action ◽  
Content Type

ABSTRACT To date, there is only one drug in use, praziquantel, to treat more than 250 million people afflicted with schistosomiasis, a debilitating parasitic disease. The aryl hydantoin Ro 13-3978 is a promising drug candidate with in vivo activity superior to that of praziquantel against both adult and juvenile Schistosoma mansoni organisms. Given the drug's contrasting low activity in vitro and the timing of its onset of action in vivo, it was postulated that immune-assisted parasite clearance could contribute to the drug's in vivo activity. We undertook histopathological studies to investigate this hypothesis. Infected mice were treated with an effective dose of Ro 13-3978 (100 mg/kg of body weight) and were dissected before and after the drug's in vivo onset of action. The veins and livers were excised, paraffin-embedded, and sectioned, and macrophages (IBA-1), neutrophils (Neutro), B cells (CD45R), and T cells (CD3) were stained by immunohistochemistry. For comparison, samples from infected untreated mice and mice treated with effective doses of praziquantel (400 mg/kg), oxamniquine (200 mg/kg), and mefloquine (200 mg/kg) were examined. At 24 h after treatment with Ro 13-3978, significant macrophage recruitment to the veins was observed, along with a modest increase in circulating B cells, and at 48 h, neutrophils and T cells are also present. Treatment with praziquantel and oxamniquine showed similar patterns of recruitment but with comparatively higher cellular levels, whereas mefloquine treatment resulted in minimal cell recruitment until 3 days posttreatment. Our study sheds light on the immediate immune responses to antischistosomal treatment in mice and provides further insight into immune effector mechanisms of schistosome clearance.

scholarly journals The New Pyrazolyltetrazole Derivative MSN20 Is Effective via Oral Delivery against Cutaneous Leishmaniasis

2014 ◽  
Vol 58 (10) ◽  
pp. 6290-6293 ◽  
Author(s):  
Viviane dos Santos Faiões ◽  
Maurício Silva dos Santos ◽  
Alice Maria Rolim Bernardino ◽  
Edézio Ferreira Cunha-Júnior ◽  
Marilene Marcuzzo do Canto Cavalheiro ◽  
...  
Keyword(s):  
Effective Treatment ◽  
Cutaneous Leishmaniasis ◽  
Oral Delivery ◽  
Inhibitory Concentration ◽  
Oral Treatment ◽  
Parasite Load ◽  
Leishmania Amazonensis ◽  
Lead Compound ◽  
Content Type ◽  
Medical Need

ABSTRACTAn orally delivered, safe and effective treatment for leishmaniasis is an unmet medical need. Azoles and the pyrazolylpyrimidine allopurinol present leishmanicidal activity, but their clinical efficacies are variable. Here, we describe the activity of the new pyrazolyltetrazole hybrid, 5-[5-amino-1-(4′-methoxyphenyl)1H-pyrazole-4-yl]1H-tetrazole (MSN20). MSN20 showed a 50% inhibitory concentration (IC50) of 22.3 μM against amastigotes ofLeishmania amazonensisand reduced significantly the parasite load in infected mice, suggesting its utility as a lead compound for the development of an oral treatment for leishmaniasis.

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