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1.
J Huntingtons Dis ; 13(1): 55-66, 2024.
Article in English | MEDLINE | ID: mdl-38489193

ABSTRACT

Background: Huntington's disease (HD) is a neurodegenerative disorder characterized by motor, cognitive, and psychiatric dysfunction caused by a mutant huntingtin protein. Compromised metabolic activity resulting from systemic administration of the mitochondrial toxin, 3-nitropropionic acid (3-NP), is known to mimic the pathology of HD and induce HD-like symptoms in rats. N-hexanoic-Tyr-Ile-(6)-amino hexanoic amide (PNB-0408), also known as Dihexa, has been shown to have neuroprotective and procognitive properties in animal models of Alzheimer's and Parkinson's diseases. Given the mechanism of action and success in other neurodegenerative diseases, we felt it an appropriate compound to investigate further for HD. Objective: The present study was designed to test if PNB-0408, an angiotensin IV analog, could attenuate 3-NP-induced HD-like symptoms in rats and serve as a potential therapeutic agent. Methods: Forty male Wistar rats were randomized into three groups consisting of a "vehicle" group, a "3-NP" group, and a "3-NP + PNB-0408" group. PNB-0408 was administered along with chronic exposure to 3-NP. Animal body weight, motor function, and cognitive abilities were measured for five weeks, before euthanasia and histopathological analysis. Results: Exposure to 3-NP decreased the amount of weight rats gained, impaired spatial learning and memory consolidation, and led to marked motor dysfunction. From our observations and analysis, PNB-0408 did not protect rats from the deficits induced by 3-NP neurotoxicity. Conclusions: Our findings suggest that PNB-0408 may not be an efficacious treatment strategy for preventing 3-NP-induced HD-like symptoms in a preclinical model. These data highlight the need for further research of this compound in alternate models and/or alternative approaches to managing this disorder.


Subject(s)
Angiotensin II/analogs & derivatives , Huntington Disease , Neuroprotective Agents , Rats , Male , Animals , Rats, Wistar , Huntington Disease/chemically induced , Huntington Disease/drug therapy , Huntington Disease/metabolism , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Nitro Compounds/toxicity , Nitro Compounds/therapeutic use , Propionates/toxicity , Propionates/therapeutic use , Disease Models, Animal
2.
Parasitol Res ; 123(3): 162, 2024 Mar 16.
Article in English | MEDLINE | ID: mdl-38492070

ABSTRACT

Toxocara canis (T. canis) is a gastrointestinal nematode in dogs, and its larvae also infect humans, causing severe larval migratory disease. Anthelmintic drugs have become the primary means to combat T. canis. In this study, the efficacy of nitazoxanide (NTZ) was tested against all the internal stages of T. canis, including L3 larval stage in vitro experiments and gastrointestinal worm in vivo experiments. In the in vitro experiment, after treatment with NTZ at 7.81 and 62.5 µg/mL for 12 h, the larval mortality efficacy reached 90.0 and 100.0%, respectively. In the in vivo experiments, 100 mg/kg NTZ possessed good anthelmintic efficacy against T. canis, with an egg per gram (EPG) reduction of 99.19%, and 90.00% of dogs cleared with residual worms. These results were comparable to those of the positive control drug. The highest anthelmintic efficacy was observed in the group treated with 150 mg/kg NTZ. Based on faecal egg counts, the number of T. canis eggs decreased by 100.00%, and the percentage of dogs cleared with residual worms achieved 90.00% after 7 days of treatment in the 150-mg/kg NTZ treatment group. In general, NTZ showed great potential to be applied as an anthelmintic against T. canis.


Subject(s)
Anthelmintics , Dog Diseases , Toxocara canis , Toxocariasis , Humans , Animals , Dogs , Anthelmintics/pharmacology , Anthelmintics/therapeutic use , Nitro Compounds/therapeutic use , Thiazoles/therapeutic use , Toxocariasis/drug therapy , Dog Diseases/drug therapy , Parasite Egg Count/veterinary
3.
PLoS Negl Trop Dis ; 17(12): e0011845, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38100538

ABSTRACT

Cyclosporiasis is a ubiquitous infection caused by an obligate intracellular protozoan parasite known as Cyclospora cayetanensis (C. cayetanensis). The disease is characterized by severe diarrhea which may be regrettably fatal in immunosuppressed patients. The commercially available treatment options have either severe side effects or low efficiency. In the present study, the novel formula of nitazoxanide (NTZ)-loaded nanostructured lipid carriers (NLCs) was assessed for the first time for C. cayetanensis treatment in both immunocompetent and immunosuppressed mice in comparison to commercially available drugs (trimethoprim-sulfamethoxazole (TMP-SMX) and NTZ). Swiss Albino mice were orally infected by 104 sporulated oocysts. The experimental groups were treated with the gold standard TMP-SMX, NTZ, blank NLCs and NTZ-loaded NLCs. The results demonstrated that NTZ-loaded NLCs represented the highest significant parasite percent reduction of (>98% reduction) in both immunocompetent and immunosuppressed mice designating successful tissue penetration and avoiding recurrence of infection at the end of the study. Oocysts treated with NTZ-loaded NLCs demonstrated the most mutilated rapturing morphology via scanning electron microscope examination as well as representing the most profound improvement of the histopathological picture. In conclusion, NTZ-loaded NLCs exhibited the uppermost efficacy in the treatment of cyclosporiasis. The safe nature and the anti-parasitic effect of the novel formulation encourage its use as a powerful treatment for human cyclosporiasis.


Subject(s)
Cyclospora , Cyclosporiasis , Humans , Animals , Mice , Cyclosporiasis/diagnosis , Cyclosporiasis/drug therapy , Cyclosporiasis/parasitology , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use , Nitro Compounds/therapeutic use , Oocysts , Lipids
4.
Eur Rev Med Pharmacol Sci ; 26(9): 3132-3137, 2022 05.
Article in English | MEDLINE | ID: mdl-35587063

ABSTRACT

OBJECTIVE: Antibiotic resistance and poor patient compliance with treatment cause Helicobacter pylori to show increased resistance to typical first-line therapeutic regimens. This study aimed to evaluate the efficacy of the new nitazoxanide-based treatment regimens for Helicobacter pylori infection vs. the current metronidazole-based regimens to address the problem of increasing metronidazole resistance. PATIENTS AND METHODS: This randomized clinical trial enrolled 100 patients with Helicobacter pylori infection. The patients were randomly assigned to one of two groups: group I received nitazoxanide-based triple therapy (nitazoxanide, proton pump inhibitor, and clarithromycin) for 14 days, whereas group II received standard treatment (metronidazole, omeprazole, and clarithromycin) for 14 days. On enrollment and after six weeks of treatment, all patients underwent careful history taking, full clinical examination, laboratory investigations (complete blood count, liver and renal function tests), and Helicobacter pylori stool antigen testing. RESULTS: Of the patients, 92% in the nitazoxanide group and 84% in the metronidazole group recovered from infection, with no statistically significant difference between the two groups. Patients in the nitazoxanide group showed a 54% lower risk of resistant infection (odds ratio, 0.5; 95% confidence interval, 0.161-1.555) than those in the metronidazole group. CONCLUSIONS: The nitazoxanide-based therapeutic regimen produced higher eradication rates than the standard treatment. However, the difference was not substantial in this particular group of patients.


Subject(s)
Helicobacter Infections , Helicobacter pylori , Metronidazole/therapeutic use , Nitro Compounds/therapeutic use , Adolescent , Amoxicillin/therapeutic use , Anti-Bacterial Agents , Child , Clarithromycin/therapeutic use , Drug Therapy, Combination , Helicobacter Infections/drug therapy , Humans , Proton Pump Inhibitors , Thiazoles , Treatment Outcome
5.
Parasitology ; 149(4): 490-495, 2022 04.
Article in English | MEDLINE | ID: mdl-35109958

ABSTRACT

Cutaneous leishmaniasis (CL) is a spectrum of clinical manifestations characterized by severe skin ulcerations that leads to social stigma. There are limited treatment options for CL, and the available drugs are becoming less efficacious due to drug resistance. More efficacious and safer antileishmanial drugs are needed. In this study, the biological effect of seven synthetically accessible nitroaromatic compounds was evaluated in vitro against amastigotes of Leishmania amazonensis, followed by in vivo evaluation using mouse models of CL. Two compounds (6 and 7) were active against amastigotes in vitro [half-maximal effective concentration (EC50): 4.57 ± 0.08 and 9.19 ± 0.68 µm, respectively], with selectivity indexes >50, and the other compounds were not selective. In vivo, compounds 6 and 7 (10 mg kg−1, twice a day for 14 days) failed to reduce skin lesion sizes and parasite loads determined by light microscopy of lesion imprints and quantitative polymerase chain reaction. Nevertheless, the in vitro leishmanicidal efficacy sustained their use as templates for nitroimidazole-based antileishmanial drug discovery programmes focusing on analogues with more suitable properties.


Subject(s)
Antiprotozoal Agents , Leishmania mexicana , Leishmaniasis, Cutaneous , Animals , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/therapeutic use , Leishmaniasis, Cutaneous/drug therapy , Mice , Mice, Inbred BALB C , Nitro Compounds/therapeutic use
6.
Int J Neurosci ; 132(5): 450-458, 2022 May.
Article in English | MEDLINE | ID: mdl-32901525

ABSTRACT

BACKGROUND AND PURPOSE: Huntington disease (HD) is an autosomal dominant inheritance neurodegenerative disorder. 3-Nitropropanoic acid (3-NP) is a mitochondrial toxin that induces HD-like symptoms and thus serves as a good experimental model of HD. Chrysin (5, 7-dihydroxyflavone) is a natural flavonoid that have multiple biological activities. The present work was aimed to evaluate the neuroprotective efficacy of Chrysin in rat brain, under the influence of 3-NP treatment, by studying neurobehavioral and biochemical alterations alongwith histo-architectural changes. MATERIALS AND METHODS: Male Wistar rats (220-250 g) were used in the study and were divided into three groups following randomization. Each group comprised of nine animals. Group I animals served as control group and administered with normal saline (orally) as vehicle. Animals of Group II were treated with 3-NP for four successive days, at the dose of 20 mg/kg, intraperitoneally (i.p.). Animals that received Chrysin for the period of four consecutive days with the dose of 50 mg/kg, orally twice daily (30 min pre-treatment and 6 h post-treatment) following 3-NP administration served as Group III. After the treatment regime, animals were evaluated for neurobehavioral alterations and brain homogenates were used for estimation of neurotoxicity marker activity and neurotransmitter level along with histological assessment. RESULTS: The significant alteration in neurobehavioral, biochemical and neuronal structure in striatal part of brain was observed in the 3-NP administered (Group II) animals. It was observed that co-treatment of Chrysin with 3-NP treated rats the rotarod performance, grip strength, stride length as well as monoamine oxidase activity and serotonin levels were elevated. CONCLUSION: The results of this study reveal that Chrysin treatment alleviated the neurobehavioral, biochemical and histological alterations against HD symptoms in rats.


Subject(s)
Huntington Disease , Neuroprotective Agents , Neurotoxicity Syndromes , Animals , Flavonoids/pharmacology , Huntington Disease/chemically induced , Huntington Disease/drug therapy , Male , Motor Activity/physiology , Neuroprotective Agents/therapeutic use , Neurotoxicity Syndromes/drug therapy , Neurotoxicity Syndromes/etiology , Nitro Compounds/therapeutic use , Nitro Compounds/toxicity , Oxidative Stress , Rats , Rats, Wistar
7.
Vet Dermatol ; 33(1): 83-86, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34402115

ABSTRACT

Superficial suppurative necrolytic dermatitis (SSND) of miniature schnauzers is a rare cutaneous and visceral reaction pattern associated with shampoo. This report describes SSND in a miniature schnauzer associated with application of an imidacloprid and flumethrin collar. Histopathology was consistent with SSND. Lesions resolved after treatment with methylprednisolone and marbofloxacin.


La dermatite nécrolytique suppurative superficielle (SSND) des schnauzers miniatures est un patron réactionnel viscéral et cutané rare associé au shampooing. Cet article décrit SSND chez un schnauzer miniature associé à l'application d'un collier d'imidaclopride et de fluméthrine. L'histopathologie était compatible avec SSND. Les lésions se sont résolues après traitement avec méthylprednisolone et marbofloxacine.


La dermatitis necrolítica supurativa superficial (SSND) de los Schnauzer miniatura es un patrón de reacción cutánea y visceral poco común descrito en asociación con algunos champúes. Este informe describe SSND en un Schnauzer miniatura asociado con la aplicación de un collar de imidacloprid y flumetrina. La histopatología fue compatible con SSND. Las lesiones se resolvieron tras el tratamiento con metilprednisolona y marbofloxacina.


A dermatite necrolítica supurativa superficial (DNSS) de schnauzers miniatura é um raro padrão reacional cutâneo e visceral associado ao uso de shampoos. Este relato descreve um caso de DNSS em um schnauzer miniatura associado à aplicação de uma coleira de imidaclorprida e flumetrina. A histopatologia foi consistente com DNSS. As lesões foram resolvidas após o tratamento com metilprednisolona e marbofloxacino.


Subject(s)
Dermatitis , Dog Diseases , Animals , Dermatitis/drug therapy , Dermatitis/veterinary , Dogs , Neonicotinoids/therapeutic use , Nitro Compounds/therapeutic use , Pyrethrins
8.
Expert Rev Anti Infect Ther ; 20(1): 17-21, 2022 01.
Article in English | MEDLINE | ID: mdl-34088250

ABSTRACT

INTRODUCTION: Mediators of immunity and inflammation are playing a crucial role in COVID-19 pathogenesis and complications as demonstrated by several genetic and clinical studies. Thus, repurposing of drugs that possess anti-inflammatory and/or immune-modulatory effects for COVID-19 is considered a rational approach. AREAS COVERED: We analyze selected studies that correlated COVID-19 with dysregulated interferon and inflammatory responses while reflecting on our academic and real-life experience using non-steroidal anti-inflammatory drugs, nitazoxanide and azithromycin for management of COVID-19. Moreover, we interpret the results that suggested a potential survival benefit of low-dose aspirin and colchicine when used for COVID-19. EXPERT OPINION: Nitazoxanide/azithromycin combination has been first hypothesized by the author and practiced by him and several researchers to benefit COVID-19 patients due to a potential ability to augment the natural interferon response as well as their positive immunomodulatory effects on several cytokines. Furthermore, NSAIDs, that are unfortunately currently at best of second choice after paracetamol, have been early postulated and clinically practiced by the author to prevent or ameliorate COVID-19 complications and mortality due to their anti-inflammatory and immunomodulatory properties. Finally, we repeat our previous call to adopt our observational study that used these drugs in sufficiently powered double blind randomized clinical trials.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Azithromycin/therapeutic use , COVID-19 Drug Treatment , COVID-19/immunology , Cytokine Release Syndrome/drug therapy , Drug Repositioning , Interleukin-6/antagonists & inhibitors , Nitro Compounds/therapeutic use , Thiazoles/therapeutic use , COVID-19/complications , Cytokine Release Syndrome/complications , Cytokine Release Syndrome/immunology , Humans , Interferons/immunology , Interleukin-6/immunology , Observational Studies as Topic , SARS-CoV-2/pathogenicity
9.
Viruses ; 13(10)2021 10 09.
Article in English | MEDLINE | ID: mdl-34696470

ABSTRACT

Feline calicivirus (FCV) causes upper respiratory tract disease (URTD) and sporadic outbreaks of virulent systemic disease (FCV-VSD). The basis for the increased pathogenicity of FCV-VSD viruses is incompletely understood, and antivirals for FCV-VSD have yet to be developed. We investigated the clinicoepidemiology and viral features of three FCV-VSD outbreaks in Australia and evaluated the in vitro efficacy of nitazoxanide (NTZ), 2'-C-methylcytidine (2CMC) and NITD-008 against FCV-VSD viruses. Overall mortality among 23 cases of FCV-VSD was 39%. Metagenomic sequencing identified five genetically distinct FCV lineages within the three outbreaks, all seemingly evolving in situ in Australia. Notably, no mutations that clearly distinguished FCV-URTD from FCV-VSD phenotypes were identified. One FCV-URTD strain likely originated from a recombination event. Analysis of seven amino-acid residues from the hypervariable E region of the capsid in the cultured viruses did not support the contention that properties of these residues can reliably differentiate between the two pathotypes. On plaque reduction assays, dose-response inhibition of FCV-VSD was obtained with all antivirals at low micromolar concentrations; NTZ EC50, 0.4-0.6 µM, TI = 21; 2CMC EC50, 2.7-5.3 µM, TI > 18; NITD-008, 0.5 to 0.9 µM, TI > 111. Investigation of these antivirals for the treatment of FCV-VSD is warranted.


Subject(s)
Antiviral Agents/therapeutic use , Calicivirus, Feline/isolation & purification , Cat Diseases/drug therapy , Cat Diseases/epidemiology , Disease Outbreaks/veterinary , Animals , Australia , Caliciviridae Infections/pathology , Caliciviridae Infections/veterinary , Caliciviridae Infections/virology , Calicivirus, Feline/classification , Calicivirus, Feline/genetics , Capsid/drug effects , Cat Diseases/pathology , Cat Diseases/virology , Cats , Cytidine/analogs & derivatives , Cytidine/therapeutic use , Female , Male , Metagenome , Nitro Compounds/therapeutic use , Phylogeny , Thiazoles/therapeutic use
10.
Sci Rep ; 11(1): 17788, 2021 09 07.
Article in English | MEDLINE | ID: mdl-34493738

ABSTRACT

Bile acid profiles are altered in obese individuals with asthma. Thus, we sought to better understand how obesity-related systemic changes contribute to lung pathophysiology. We also test the therapeutic potential of nitro-oleic acid (NO2-OA), a regulator of metabolic and inflammatory signaling pathways, to mitigate allergen and obesity-induced lung function decline in a murine model of asthma. Bile acids were measured in the plasma of healthy subjects and individuals with asthma and serum and lung tissue of mice with and without allergic airway disease (AAD). Lung function, indices of inflammation and hepatic bile acid enzyme expression were measured in obese mice with house dust mite-induced AAD treated with vehicle or NO2-OA. Serum levels of glycocholic acid and glycoursodeoxycholic acid clinically correlate with body mass index and airway hyperreactivity whereas murine levels of ß-muricholic acid and tauro-ß-muricholic acid were significantly increased and positively correlated with impaired lung function in obese mice with AAD. NO2-OA reduced murine bile acid levels by modulating hepatic expression of bile acid synthesis enzymes, with a concomitant reduction in small airway resistance and tissue elastance. Bile acids correlate to body mass index and lung function decline and the signaling actions of nitroalkenes can limit AAD by modulating bile acid metabolism, revealing a potential pharmacologic approach to improving the current standard of care.


Subject(s)
Asthma/metabolism , Asthma/physiopathology , Bile Acids and Salts/metabolism , Fatty Acids/physiology , Lung/physiopathology , Nitro Compounds/therapeutic use , Obesity/metabolism , Oleic Acids/therapeutic use , Adolescent , Adult , Animals , Anti-Asthmatic Agents/therapeutic use , Antigens, Dermatophagoides/toxicity , Asthma/drug therapy , Asthma/etiology , Diet, High-Fat/adverse effects , Drug Evaluation, Preclinical , Fatty Acids/chemistry , Female , Forced Expiratory Volume , Glycocholic Acid/blood , Humans , Liver/drug effects , Liver/metabolism , Male , Mice , Mice, Inbred C57BL , Middle Aged , Obesity/complications , Obesity/physiopathology , Respiratory Hypersensitivity/chemically induced , Respiratory Hypersensitivity/drug therapy , Respiratory Hypersensitivity/metabolism , Thinness , Ursodeoxycholic Acid/analogs & derivatives , Ursodeoxycholic Acid/blood , Vital Capacity , Young Adult
11.
Int J Mol Sci ; 22(16)2021 Aug 22.
Article in English | MEDLINE | ID: mdl-34445757

ABSTRACT

Nitro-oleic acid (NO2-OA), a nitric oxide (NO)- and nitrite (NO2-)-derived electrophilic fatty acid metabolite, displays anti-inflammatory and anti-fibrotic signaling actions and therapeutic benefit in murine models of ischemia-reperfusion, atrial fibrillation, and pulmonary hypertension. Muscle LIM protein-deficient mice (Mlp-/-) develop dilated cardiomyopathy (DCM), characterized by impaired left ventricular function and increased ventricular fibrosis at the age of 8 weeks. This study investigated the effects of NO2-OA on cardiac function in Mlp-/- mice both in vivo and in vitro. Mlp-/- mice were treated with NO2-OA or vehicle for 4 weeks via subcutaneous osmotic minipumps. Wildtype (WT) littermates treated with vehicle served as controls. Mlp-/- mice exhibited enhanced TGFß signalling, fibrosis and severely reduced left ventricular systolic function. NO2-OA treatment attenuated interstitial myocardial fibrosis and substantially improved left ventricular systolic function in Mlp-/- mice. In vitro studies of TGFß-stimulated primary cardiac fibroblasts further revealed that the anti-fibrotic effects of NO2-OA rely on its capability to attenuate fibroblast to myofibroblast transdifferentiation by inhibiting phosphorylation of TGFß downstream targets. In conclusion, we demonstrate a substantial therapeutic benefit of NO2-OA in a murine model of DCM, mediated by interfering with endogenously activated TGFß signaling.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Cardiomyopathy, Dilated/drug therapy , Nitro Compounds/therapeutic use , Oleic Acids/therapeutic use , Ventricular Function, Left/drug effects , Animals , Anti-Inflammatory Agents/pharmacology , Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/pathology , Drug Evaluation, Preclinical , Fibroblasts/metabolism , Fibrosis , Heart/drug effects , LIM Domain Proteins/genetics , Mice , Muscle Proteins/genetics , Myocardium/metabolism , Nitro Compounds/pharmacology , Oleic Acids/pharmacology , Transforming Growth Factor beta/metabolism
12.
Parasitology ; 148(11): 1320-1327, 2021 09.
Article in English | MEDLINE | ID: mdl-34247670

ABSTRACT

Drug combinations have been evaluated for Chagas disease in an attempt to improve efficacy and safety. In this line, the objective of this work is to assess the effects of treatment with nitro drugs combinations using benznidazole (BZ) or nifurtimox (NFX) plus the sulfone metabolite of fexinidazole (fex-SFN) in vitro and in vivo on Trypanosoma cruzi infection. The in vitro interaction of fex-SFN and BZ or NFX against infected H9c2 cells by the Y strain was classified as an additive (0.5⩾ΣFIC<4), suggesting the possibility of a dose reduction in the in vivo T. cruzi infection. Next, the effect of combining suboptimal doses was assessed in an acute model of murine T. cruzi infection. Drug combinations led to a faster suppression of parasitemia than monotherapies. Also, the associations led to higher cure levels than those in the reference treatment BZ 100 mg day−1 (57.1%) (i.e. 83.3% with BZ/fex-SFN and 75% with NFX/fex-SFN). Importantly, toxic effects resulting from the associations were not observed, according to weight gain and hepatic enzyme levels in the serum of experimental animals. Taken together, this study is a starting point to explore the potential effects of nitro drugs combinations in preclinical models of kinetoplastid-related infections.


Subject(s)
Chagas Disease/drug therapy , Nitro Compounds/therapeutic use , Animals , Drug Therapy, Combination , Female , Humans , Inhibitory Concentration 50 , Mice , Neglected Diseases/drug therapy , Nifurtimox/adverse effects , Nifurtimox/therapeutic use , Nitro Compounds/adverse effects , Nitroimidazoles/adverse effects , Nitroimidazoles/metabolism , Nitroimidazoles/therapeutic use , Real-Time Polymerase Chain Reaction , Sulfones/adverse effects , Sulfones/therapeutic use
13.
Int J Mol Sci ; 22(9)2021 Apr 29.
Article in English | MEDLINE | ID: mdl-33946824

ABSTRACT

Red blood cells (RBCs) serve a variety of functions beyond mere oxygen transport both in health and pathology. Notably, RRx-001, a minimally toxic pleiotropic anticancer agent with macrophage activating and vascular normalization properties currently in Phase III trials, induces modification to RBCs which could promote vascular adhesion similar to sickle cells. This study assessed whether RBCs exposed to RRx-001 adhere to the tumor microvasculature and whether this adhesion alters tumor viability. We next investigated the biomechanics of RBC adhesion in the context of local inflammatory cytokines after treatment with RRx-001 as a potential mechanism for preferential tumor aggregation. Human HEP-G2 and HT-29 tumor cells were subcutaneously implanted into nu/nu mice and were infused with RRx-001-treated and Technetium-99m (99mTc)-labeled blood. RBC adhesion was quantified in an in vitro human umbilical vein endothelial cell (HUVEC) assay under both normoxic and hypoxic conditions with administration of either lipopolysaccharide (LPS) or Tumor necrosis alpha (TNFα) to mimic the known inflammation in the tumor microenvironment. One hour following administration of 99mTc labeled RBCs treated with 10 mg/kg RRx-001, we observed an approximate 2.0-fold and 1.5-fold increase in 99mTc-labeled RBCs compared to vehicle control in HEPG2 and HT-29 tumor models, respectively. Furthermore, we observed an approximate 40% and 36% decrease in HEP-G2 and HT-29 tumor weight, respectively, following treatment with RRx-001. To quantify RBC adhesive potential, we determined τ50, or the shear stress required for 50% disassociation of RBCs from HUVECs. After administration of TNF-α under normoxia, τ50 was determined to be 4.5 dynes/cm2 (95% CI: 4.3-4.7 dynes/cm2) for RBCs treated with 10 µM RRx-001, which was significantly different (p < 0.05) from τ50 in the absence of treatment. Under hypoxic conditions, the difference of τ50 with (4.8 dynes/cm2; 95% CI: 4.6-5.1 dynes/cm2) and without (2.6 dynes/cm2; 95% CI: 2.4-2.8 dynes/cm2) 10 µM RRx-001 treatment was exacerbated (p = 0.05). In conclusion, we demonstrated that RBCs treated with RRx-001 preferentially aggregate in HEP-G2 and HT-29 tumors, likely due to interactions between RRx-001 and cysteine residues within RBCs. Furthermore, RRx-001 treated RBCs demonstrated increased adhesive potential to endothelial cells upon introduction of TNF-α and hypoxia suggesting that RRx-001 may induce preferential adhesion in the tumor but not in other tissues with endothelial dysfunction due to conditions prevalent in older cancer patients such as heart disease or diabetic vasculopathy.


Subject(s)
Antineoplastic Agents/pharmacology , Azetidines/pharmacology , Endothelial Cells/cytology , Erythrocyte Membrane/drug effects , Nitro Compounds/pharmacology , Animals , Antineoplastic Agents/therapeutic use , Azetidines/therapeutic use , Cell Adhesion/drug effects , Cell Hypoxia , Cysteine/chemistry , Cytokines/metabolism , Endothelial Cells/chemistry , Erythrocyte Aggregation/drug effects , Erythrocyte Membrane/chemistry , HT29 Cells/transplantation , Hep G2 Cells/transplantation , Human Umbilical Vein Endothelial Cells , Humans , Lipopolysaccharides/pharmacology , Membrane Lipids/biosynthesis , Mice , Mice, Nude , Neoplasms/blood supply , Neoplasms, Experimental/blood supply , Neoplasms, Experimental/drug therapy , Nitro Compounds/therapeutic use , Phosphatidylserines/biosynthesis , Receptors, Cell Surface/biosynthesis , Shear Strength , Tumor Microenvironment , Tumor Necrosis Factor-alpha/pharmacology
14.
Biochem Pharmacol ; 190: 114588, 2021 08.
Article in English | MEDLINE | ID: mdl-33957094

ABSTRACT

Bladder cancer is one of the most common malignancy in the urinary tract with high recurrence and drug resistance in clinics. Alternative treatments from existing drugs might be a promising strategy. Nitazoxanide (NTZ), an FDA-approved antiprotozoal drug, has got increasingly noticed because of its favorable safety profile and antitumor potential, yet the effects in bladder cancer and underlying mechanisms remain poorly understood. Herein, we find that NTZ induces mitochondrial damage and mitophagy initiation through PINK1-generated phospho-ubiquitin(pS65-Ub) and autophagy receptor-mediated pathway even in the absence of Atg5/Beclin1. Meanwhile, NTZ inhibits lysosomal degradation activity, leading to mitophagy flux impairment at late stage. Mitochondrial reactive oxygen species (ROS) production is critical in this process, as eliminating ROS with N-acetylcysteine (NAC) efficiently inhibits PINK1 signaling-mediated mitophagy initiation and alleviates lysosomal dysfunction. Co-treatment with NTZ and autophagy inhibitor Chloroquine (CQ) to aggravate mitophagy flux impairment promotes NTZ-induced apoptosis, while alleviation of mitophagy flux impairment with ROS scavenger reduces cell death. Moreover, we also discover a similar signaling response in the 3D bladder tumor spheroid after NTZ exposure. In vivo study reveals a significant inhibition of orthotopic bladder tumors with no obvious systemic toxicity. Together, our results uncover the anti-tumor activities of NTZ with the involvement of ROS-mediated mitophagy modulation at different stages and demonstrate it as a potential drug candidate for fighting against bladder tumors.


Subject(s)
Antineoplastic Agents/pharmacology , Lysosomes/metabolism , Mitophagy/drug effects , Nitro Compounds/pharmacology , Reactive Oxygen Species/metabolism , Thiazoles/pharmacology , Urinary Bladder Neoplasms/metabolism , Animals , Antineoplastic Agents/therapeutic use , Antiparasitic Agents/pharmacology , Antiparasitic Agents/therapeutic use , Dose-Response Relationship, Drug , Female , HEK293 Cells , Humans , Lysosomes/drug effects , Mice , Mice, Inbred BALB C , Mice, Nude , Mitophagy/physiology , Nitro Compounds/therapeutic use , Reactive Oxygen Species/antagonists & inhibitors , Thiazoles/therapeutic use , Urinary Bladder Neoplasms/drug therapy
15.
J Med Chem ; 64(11): 7261-7271, 2021 06 10.
Article in English | MEDLINE | ID: mdl-34043360

ABSTRACT

After extensive screening of aerospace compounds in an effort to source a novel anticancer agent, RRx-001, a first-in-class dinitroazetidine small molecule, was selected for advancement into preclinical and clinical development. RRx-001 is a minimally toxic small molecule with a distinct chemical structure and mechanism of action. The paradox of RRx-001 is that it mediates both antitumor cytotoxicity and normal tissue protection. The question of exactly how RRx-001 does this, and by means of what mechanism(s), depending on the route of delivery, intravenous or intratumoral, are explored. RRx-001 is currently in phase 2 and 3 clinical trials for the treatment of multiple solid tumor malignancies and as a supportive care drug.


Subject(s)
Antineoplastic Agents/chemistry , Azetidines/chemistry , CD47 Antigen/metabolism , Nitro Compounds/chemistry , Proto-Oncogene Proteins c-myc/metabolism , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Azetidines/pharmacology , Azetidines/therapeutic use , CD47 Antigen/genetics , Cell Proliferation/drug effects , Cell Survival/drug effects , Down-Regulation/drug effects , Half-Life , Humans , Immunogenic Cell Death/drug effects , Male , Mice , Mice, Inbred C3H , Neoplasms/diagnostic imaging , Neoplasms/drug therapy , Nitro Compounds/pharmacology , Nitro Compounds/therapeutic use , Positron-Emission Tomography , Proto-Oncogene Proteins c-myc/genetics , Structure-Activity Relationship , Transplantation, Heterologous , Tumor-Associated Macrophages/cytology , Tumor-Associated Macrophages/drug effects , Tumor-Associated Macrophages/metabolism
16.
Cell Mol Immunol ; 18(6): 1425-1436, 2021 06.
Article in English | MEDLINE | ID: mdl-33972740

ABSTRACT

The NLRP3 inflammasome plays a crucial role in innate immune-mediated inflammation and contributes to the pathogenesis of multiple autoinflammatory, metabolic and neurodegenerative diseases, but medications targeting the NLRP3 inflammasome are not available for clinical use. RRx-001 is a well-tolerated anticancer agent currently being investigated in phase III clinical trials, but its effects on inflammatory diseases are not known. Here, we show that RRx-001 is a highly selective and potent NLRP3 inhibitor that has strong beneficial effects on NLRP3-driven inflammatory diseases. RRx-001 inhibits the activation of the canonical, noncanonical, and alternative NLRP3 inflammasomes but not the AIM2, NLRC4 or Pyrin inflammasomes. Mechanistically, RRx-001 covalently binds to cysteine 409 of NLRP3 via its bromoacetyl group and therefore blocks the NLRP3-NEK7 interaction, which is critical for the assembly and activation of the NLRP3 inflammasome. More importantly, RRx-001 treatment attenuates the symptoms of lipopolysaccharide (LPS)-induced systemic inflammation, dextran sulfate sodium (DSS)-induced colitis and experimental autoimmune encephalomyelitis (EAE) in mice. Thus, our study identifies RRx-001 as a new potential therapeutic agent for NLRP3-driven diseases.


Subject(s)
Azetidines/therapeutic use , Inflammation/drug therapy , NLR Family, Pyrin Domain-Containing 3 Protein/antagonists & inhibitors , Nitro Compounds/therapeutic use , Animals , Azetidines/chemistry , Azetidines/pharmacology , CARD Signaling Adaptor Proteins/metabolism , Colitis/chemically induced , Colitis/immunology , Colitis/pathology , Cysteine/metabolism , Dextran Sulfate , Encephalomyelitis, Autoimmune, Experimental/chemically induced , Encephalomyelitis, Autoimmune, Experimental/immunology , Encephalomyelitis, Autoimmune, Experimental/pathology , Inflammasomes/antagonists & inhibitors , Inflammasomes/metabolism , Inflammation/immunology , Inflammation/pathology , Lipopolysaccharides , Macrophages/metabolism , Mice, Inbred C57BL , NIMA-Related Kinases/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/chemistry , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Nitro Compounds/chemistry , Nitro Compounds/pharmacology , Protein Domains
17.
PLoS Negl Trop Dis ; 15(3): e0009057, 2021 03.
Article in English | MEDLINE | ID: mdl-33705395

ABSTRACT

Cryptosporidium is a widely distributed enteric parasite that has an increasingly appreciated pathogenic role, particularly in pediatric diarrhea. While cryptosporidiosis has likely affected humanity for millennia, its recent "emergence" is largely the result of discoveries made through major epidemiologic studies in the past decade. There is no vaccine, and the only approved medicine, nitazoxanide, has been shown to have efficacy limitations in several patient groups known to be at elevated risk of disease. In order to help frontline health workers, policymakers, and other stakeholders translate our current understanding of cryptosporidiosis into actionable guidance to address the disease, we sought to assess salient issues relating to clinical management of cryptosporidiosis drawing from a review of the literature and our own field-based practice. This exercise is meant to help inform health system strategies for improving access to current treatments, to highlight recent achievements and outstanding knowledge and clinical practice gaps, and to help guide research activities for new anti-Cryptosporidium therapies.


Subject(s)
Antiparasitic Agents/therapeutic use , Cryptosporidiosis/drug therapy , Cryptosporidiosis/epidemiology , Cryptosporidium/drug effects , Nitro Compounds/therapeutic use , Thiazoles/therapeutic use , Child, Preschool , Cryptosporidium/immunology , Diarrhea/parasitology , Disease Outbreaks , Fluid Therapy , Humans , Immunocompromised Host/immunology , Infant , Infant, Newborn
19.
J Med Microbiol ; 70(3)2021 Mar.
Article in English | MEDLINE | ID: mdl-33625354

ABSTRACT

Introduction. Cryptosporidium parvum causes intestinal parasitic infections affecting both immunosuppressed and immunocompetent individuals.Gap statement. Given the absence of effective treatments for cryptosporidiosis, especially in immunodeficient patients, the present study was designed to assess the therapeutic efficacy of secnidazole (SEC) and its combination with nitazoxanide (NTZ) in comparison to single NTZ treatment in relation to the immune status of a murine model of C. parvum infection.Methodology. The infected groups were administered NTZ, SEC or NTZ-SEC for three or five successive doses. At days 10 and 12 post-infection (p.i.), the mice were sacrificed, and the efficacy of the applied drugs was evaluated by comparing the histopathological alterations in ileum and measuring the T helper Th1 (interferon gamma; IFN-γ), Th2 [interleukin (IL)-4 and IL-10] and Th17 (IL-17) cytokine profiles in serum.Results. The NTZ-SEC combination recorded the maximal reduction of C. parvum oocyst shedding, endogenous stages count and intestinal histopathology, regardless of the immune status of the infected mice. The efficacy of NTZ-SEC was dependent on the period of administration, as the 5 day-based treatment protocol was also more effective than the 3 day-based one in terms of immunocompetence and immunosuppression. The present treatment schedule induced an immunomodulatory effect from SEC that developed a protective immune response against C. parvum infection with reduced production of serum IL-17, IFN-γ, IL-4 and IL-10.Conclusions. Application of NTZ-SEC combined therapy may be useful in treatment of C. parvum, especially in cases involving immunosuppression.


Subject(s)
Antiprotozoal Agents/therapeutic use , Cryptosporidiosis/drug therapy , Immunomodulation/drug effects , Metronidazole/analogs & derivatives , Nitro Compounds/therapeutic use , Thiazoles/therapeutic use , Animals , Cryptosporidiosis/immunology , Cryptosporidiosis/parasitology , Cryptosporidiosis/pathology , Cryptosporidium parvum/drug effects , Cytokines/blood , Disease Models, Animal , Drug Administration Schedule , Drug Therapy, Combination , Ileum/drug effects , Ileum/parasitology , Ileum/pathology , Immunocompromised Host , Male , Metronidazole/therapeutic use , Mice , Parasite Load
20.
J Med Virol ; 93(5): 3176-3183, 2021 05.
Article in English | MEDLINE | ID: mdl-33590901

ABSTRACT

This trial compared the rate and time of viral clearance in subjects receiving a combination of nitazoxanide, ribavirin, and ivermectin plus Zinc versus those receiving supportive treatment. This non-randomized controlled trial included 62 patients on the triple combination treatment versus 51 age- and sex-matched patients on routine supportive treatment. all of them confirmed cases by positive reverse-transcription polymerase chain reaction of a nasopharyngeal swab. Trial results showed that the clearance rates were 0% and 58.1% on the 7th day and 13.7% and 73.1% on the 15th day in the supportive treatment and combined antiviral groups, respectively. The cumulative clearance rates on the 15th day are 13.7% and 88.7% in the supportive treatment and combined antiviral groups, respectively. This trial concluded by stating that the combined use of nitazoxanide, ribavirin, and ivermectin plus zinc supplement effectively cleared the SARS-COV2 from the nasopharynx in a shorter time than symptomatic therapy.


Subject(s)
COVID-19 Drug Treatment , Ivermectin/therapeutic use , Nitro Compounds/therapeutic use , Ribavirin/therapeutic use , SARS-CoV-2 , Thiazoles/therapeutic use , Zinc/therapeutic use , Adult , Antimetabolites/administration & dosage , Antimetabolites/therapeutic use , Antiparasitic Agents/administration & dosage , Antiparasitic Agents/therapeutic use , Female , Humans , Ivermectin/administration & dosage , Male , Nitro Compounds/administration & dosage , Ribavirin/administration & dosage , Thiazoles/administration & dosage , Trace Elements/administration & dosage , Trace Elements/therapeutic use , Zinc/administration & dosage
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