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1.
Biochem Pharmacol ; 197: 114913, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35032461

RESUMEN

Nitazoxanide and related thiazolides are a novel class of anti-infectious agents against protozoan parasites, bacteria and viruses. In recent years, it is demonstrated that thiazolides can also induce cell cycle arrest and apoptotic cell death in cancer cells. Due to their fast proliferating nature, cancer cells highly depend on the proteasome system to remove aberrant proteins. Many of these aberrant proteins are regulators of cell cycle progression and apoptosis, such as the cyclins, BCL2 family members and nuclear factor of κB (NF-κB). Here, we demonstrate at both molecular and cellular levels that the 20S proteasome is a direct target of NTZ and related thiazolides. By concurrently inhibiting the multiple catalytic subunits of 20S proteasome, NTZ promotes cell cycle arrest and triggers cell death in colon cancer cells, either directly or as a sensitizer to other anti-tumor agents, especially doxorubicin. We further show that the binding mode of NTZ in the ß5 subunit of the 20S proteasome is different from that of bortezomib and other existing proteasome inhibitors. These findings provide new insights in the design of novel small molecular proteasome inhibitors as anti-tumor agents suitable for solid tumor treatment in an oral dosing form.


Asunto(s)
Antineoplásicos/metabolismo , Muerte Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Nitrocompuestos/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/metabolismo , Tiazoles/metabolismo , Animales , Antineoplásicos/administración & dosificación , Células CACO-2 , Muerte Celular/fisiología , Relación Dosis-Respuesta a Droga , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Nitrocompuestos/administración & dosificación , Complejo de la Endopetidasa Proteasomal/química , Inhibidores de Proteasoma/administración & dosificación , Unión Proteica/efectos de los fármacos , Unión Proteica/fisiología , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Tiazoles/administración & dosificación
2.
Nutr Neurosci ; 25(1): 100-109, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32093571

RESUMEN

Background: Piperine (PIP) is a powerful anti-oxidant and anti-inflammatory alkaloid which has been widely used in the treatment of various pathological conditions. However, few studies have clearly discussed the protective effects and potential mechanism of PIP in different neurological diseases. The aim of this study was to investigate the neuroprotective effect of PIP against 3-nitropropioninc acid (3-NP) induced neurobehavioral, biochemical and histopathological alterations in animals.Methods: Adult male Wistar rats were randomly divided into three groups. Group 1, the vehicle administered control group, received normal saline (p.o.). Group 2 received 3-NP (20 mg/kg.b.wt., i.p.) for 4 consecutive days. Group 3 received PIP (10 mg/kg.b.wt., p.o.) twice daily for a period of 4 days, 30 min before and 6 h after the 3-NP injection. Upon termination of treatment schedule, behavioral experiments were performed to access the behavioral outcomes. The brain striatal tissue was used for the estimation of monoamine oxidase activity and serotonin level. In addition, astrocytes activation was observed by GFAP immunostaining.Results: Our results showed that 3-NP induced behavioral impairments are attenuated by PIP co-treatment. Next, the extent of neuronal loss and astrocytes activation was reduced in the striatal brain region in PIP treated rats. Finally, it was observed that PIP alleviated the behavioral, biochemical, immunohistochemical and histological alterations.Conclusion: The results of the current study reveal the neuroprotective competency of PIP against Huntington disease like symptoms in rats.


Asunto(s)
Alcaloides/uso terapéutico , Benzodioxoles/uso terapéutico , Enfermedad de Huntington/tratamiento farmacológico , Trastornos Mentales/prevención & control , Fármacos Neuroprotectores , Nitrocompuestos/administración & dosificación , Piperidinas/uso terapéutico , Alcamidas Poliinsaturadas/uso terapéutico , Propionatos/administración & dosificación , Animales , Astrocitos/efectos de los fármacos , Astrocitos/fisiología , Conducta Animal/efectos de los fármacos , Cuerpo Estriado/química , Cuerpo Estriado/patología , Modelos Animales de Enfermedad , Enfermedad de Huntington/inducido químicamente , Enfermedad de Huntington/fisiopatología , Masculino , Monoaminooxidasa/análisis , Neuronas/efectos de los fármacos , Ratas , Ratas Wistar , Serotonina/análisis
3.
Clin Pharmacol Ther ; 111(3): 585-594, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34699618

RESUMEN

Repurposing approved drugs may rapidly establish effective interventions during a public health crisis. This has yielded immunomodulatory treatments for severe coronavirus disease 2019 (COVID-19), but repurposed antivirals have not been successful to date because of redundancy of the target in vivo or suboptimal exposures at studied doses. Nitazoxanide is a US Food and Drug Administration (FDA) approved antiparasitic medicine, that physiologically-based pharmacokinetic (PBPK) modeling has indicated may provide antiviral concentrations across the dosing interval, when repurposed at higher than approved doses. Within the AGILE trial platform (NCT04746183) an open label, adaptive, phase I trial in healthy adult participants was undertaken with high-dose nitazoxanide. Participants received 1,500 mg nitazoxanide orally twice-daily with food for 7 days. Primary outcomes were safety, tolerability, optimum dose, and schedule. Intensive pharmacokinetic (PK) sampling was undertaken day 1 and 5 with minimum concentration (Cmin ) sampling on days 3 and 7. Fourteen healthy participants were enrolled between February 18 and May 11, 2021. All 14 doses were completed by 10 of 14 participants. Nitazoxanide was safe and with no significant adverse events. Moderate gastrointestinal disturbance (loose stools or diarrhea) occurred in 8 participants (57.1%), with urine and sclera discoloration in 12 (85.7%) and 9 (64.3%) participants, respectively, without clinically significant bilirubin elevation. This was self-limiting and resolved upon drug discontinuation. PBPK predictions were confirmed on day 1 but with underprediction at day 5. Median Cmin was above the in vitro target concentration on the first dose and maintained throughout. Nitazoxanide administered at 1,500 mg b.i.d. with food was safe with acceptable tolerability a phase Ib/IIa study is now being initiated in patients with COVID-19.


Asunto(s)
Antivirales/administración & dosificación , Nitrocompuestos/administración & dosificación , Nitrocompuestos/efectos adversos , Nitrocompuestos/farmacocinética , Tiazoles/administración & dosificación , Tiazoles/efectos adversos , Tiazoles/farmacocinética , Adulto , Antivirales/efectos adversos , Antivirales/farmacocinética , Reposicionamiento de Medicamentos , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Tratamiento Farmacológico de COVID-19
4.
Am J Trop Med Hyg ; 106(2): 441-445, 2021 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-34872064

RESUMEN

Micronutrient deficiencies and enteric infections negatively impact child growth and development. We enrolled children shortly after birth in a randomized, placebo-controlled, 2 × 2 factorial interventional trial in Haydom, Tanzania, to assess nicotinamide and/or antimicrobials (azithromycin and nitazoxanide) effect on length at 18 months of age. Cognitive score at 18 months using the Malawi Developmental Assessment Tool (MDAT), which includes gross motor, fine motor, language, and social assessments, was a secondary outcome. Here, we present the MDAT results of 1,032 children. There was no effect of nicotinamide (change in development-for-age Z score [DAZ] -0.08; 95% CI: -0.16, 0) or antimicrobials (change in DAZ 0.04; 95% CI: -0.06, 0.13) on overall MDAT score. The interventions had no effect on cognitive outcomes in subgroups defined by gender, socioeconomic status, birthweight, and birth season or on MDAT subscores. Further analyses are needed to identify targetable risk factors for impaired cognitive development in these settings.


Asunto(s)
Antiinfecciosos/administración & dosificación , Desarrollo Infantil/fisiología , Envejecimiento Cognitivo , Intervención Educativa Precoz , Niacinamida/administración & dosificación , Complejo Vitamínico B/administración & dosificación , Antiparasitarios/administración & dosificación , Azitromicina/administración & dosificación , Estudios de Cohortes , Femenino , Humanos , Lactante , Masculino , Nitrocompuestos/administración & dosificación , Estaciones del Año , Tanzanía , Tiazoles/administración & dosificación
5.
Exp Neurol ; 346: 113861, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34499902

RESUMEN

Nitro-oleic acid (OA-NO2), a nitroalkene formed in nitric oxide-dependent oxidative reactions, has been found in human plasma and is thought to regulate pathophysiological functions. Recently, accumulating evidence suggests that OA-NO2 may function as an anti-inflammatory mediator, and ameliorate the progression of diabetes and cardiovascular diseases. However, the role of OA-NO2 in ischemic brain injury remains unexplored. In this study, C57BL/6 mice were subjected to 1 h transient middle cerebral artery occlusion (MCAO) and followed by 1- 7 days of reperfusion. These mice were treated with vehicle, OA, or OA-NO2 (10 mg/kg) via tail vein injection at 2 h after the onset of MCAO. Our results show that intravenous administration of OA-NO2 led to reduced BBB leakage in ischemic brains, reduced brain infarct, and improved sensorimotor functions in response to ischemic insults when compared to OA and vehicle controls. Also, OA-NO2 significantly reduced BBB leakage-triggered infiltration of neutrophils and macrophages in the ischemic brains. Moreover, OA-NO2 treatment reduced the M1-type microglia and increased M2-type microglia. Mechanistically, OA-NO2 alleviated the decline of mRNA and protein level of major endothelial TJs including ZO-1 in stroke mice. Treatment of OA-NO2 also significantly inhibited stroke-induced inflammatory mediators, iNOS, E-selectin, P-selectin, and ICAM1, in mouse brains. In conclusion, OA-NO2 preserves BBB integrity and confers neurovascular protection in ischemic brain damage. OA-NO2-mediated brain protection may help us to develop a novel therapeutic strategy for the treatment of ischemic stroke.


Asunto(s)
Antiinflamatorios/administración & dosificación , Barrera Hematoencefálica/efectos de los fármacos , Lesiones Encefálicas/tratamiento farmacológico , Isquemia Encefálica/tratamiento farmacológico , Nitrocompuestos/administración & dosificación , Ácidos Oléicos/administración & dosificación , Animales , Barrera Hematoencefálica/metabolismo , Lesiones Encefálicas/metabolismo , Isquemia Encefálica/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL
6.
Toxicology ; 462: 152935, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34509577

RESUMEN

Imidacloprid is an insecticide belonging to neonicotinoids, a class of agonists of the nicotinic acetylcholine receptors that shows higher affinities in insects compared to mammals. However, recent evidence show that neonicotinoids can bind to the mammalian receptors, leading to detrimental responses in cultured neurons. We developed an analytical strategy which uses mass spectrometry with multiple reaction monitoring (targeted approach) and high-resolution acquisitions (untargeted approach), which were applied to quantify imidacloprid and to identify its metabolites in biological tissues after oral treatments of mice. Mouse dams were treated with doses from 0.118 mg/kg bw day up to 41 mg/kg day between gestational days 6-9. Results showed quantifiable levels of imidacloprid in plasma (from 30.48 to 5705 ng/mL) and brain (from 20.48 to 5852 ng/g) of treated mice, proving the passage through the mammalian blood-brain barrier with a high correspondence between doses and measured concentrations. Untargeted analyses allowed the identification of eight metabolites including imidacloprid-olefin, hydroxy-imidacloprid dihydroxy-imidacloprid, imidacloprid-nitrosimine, desnitro-imidacloprid, 6-chloronicotinic acid, 5-(methylsulfanyl)pyridine-2-carboxylic acid and N-imidazolidin-2-ylidenenitramide in plasma and brain. Moreover, analysis of embryonic tissues after oral treatment of mouse dams showed detectable levels of imidacloprid (816.6 ng/g after a dose of 4.1 mg/Kg bw day and 5646 ng/g after a dose of 41 mg/Kg bw day) and its metabolites, proving the permeability of the placenta barrier. Although many studies have been reported on the neurotoxicity of neonicotinoids, our study paves the way for a risk assessment in neurodevelopmental toxicity, demostrating the capability of imidacloprid and its metabolites to pass the biological barriers.


Asunto(s)
Insecticidas/farmacocinética , Espectrometría de Masas/métodos , Neonicotinoides/farmacocinética , Nitrocompuestos/farmacocinética , Administración Oral , Animales , Barrera Hematoencefálica/metabolismo , Encéfalo/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Feto/metabolismo , Insecticidas/análisis , Masculino , Ratones , Neonicotinoides/administración & dosificación , Neonicotinoides/análisis , Nitrocompuestos/administración & dosificación , Nitrocompuestos/análisis , Placenta/metabolismo , Embarazo , Distribución Tisular
7.
PLoS Med ; 18(9): e1003617, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34582462

RESUMEN

BACKGROUND: Stunting among children in low-resource settings is associated with enteric pathogen carriage and micronutrient deficiencies. Our goal was to test whether administration of scheduled antimicrobials and daily nicotinamide improved linear growth in a region with a high prevalence of stunting and enteric pathogen carriage. METHODS AND FINDINGS: We performed a randomized, 2 × 2 factorial, double-blind, placebo-controlled trial in the area around Haydom, Tanzania. Mother-child dyads were enrolled by age 14 days and followed with monthly home visits and every 3-month anthropometry assessments through 18 months. Those randomized to the antimicrobial arm received 2 medications (versus corresponding placebos): azithromycin (single dose of 20 mg/kg) at months 6, 9, 12, and 15 and nitazoxanide (3-day course of 100 mg twice daily) at months 12 and 15. Those randomized to nicotinamide arm received daily nicotinamide to the mother (250 mg pills months 0 to 6) and to the child (100 mg sachets months 6 to 18). Primary outcome was length-for-age z-score (LAZ) at 18 months in the modified intention-to-treat group. Between September 5, 2017 and August 31, 2018, 1,188 children were randomized, of whom 1,084 (n = 277 placebo/placebo, 273 antimicrobial/placebo, 274 placebo/nicotinamide, and 260 antimicrobial/nicotinamide) were included in the modified intention-to-treat analysis. The study was suspended for a 3-month period by the Tanzanian National Institute for Medical Research (NIMR) because of concerns related to the timing of laboratory testing and the total number of serious adverse events (SAEs); this resulted in some participants receiving their final study assessment late. There was a high prevalence of stunting overall (533/1,084, 49.2%). Mean 18-month LAZ did not differ between groups for either intervention (mean LAZ with 95% confidence interval [CI]: antimicrobial: -2.05 CI -2.13, -1.96, placebo: -2.05 CI -2.14, -1.97; mean difference: 0.01 CI -0.13, 0.11, p = 0.91; nicotinamide: -2.06 CI -2.13, -1.95, placebo: -2.04 CI -2.14, -1.98, mean difference 0.03 CI -0.15, 0.09, p = 0.66). There was no difference in LAZ for either intervention after adjusting for possible confounders (baseline LAZ, age in days at 18-month measurement, ward, hospital birth, birth month, years of maternal education, socioeconomic status (SES) quartile category, sex, whether the mother was a member of the Datoga tribe, and mother's height). Adverse events (AEs) and SAEs were overall similar between treatment groups for both the nicotinamide and antimicrobial interventions. Key limitations include the absence of laboratory measures of pathogen carriage and nicotinamide metabolism to provide context for the negative findings. CONCLUSIONS: In this study, we observed that neither scheduled administration of azithromycin and nitazoxanide nor daily provision of nicotinamide was associated with improved growth in this resource-poor setting with a high force of enteric infections. Further research remains critical to identify interventions toward improved early childhood growth in challenging conditions. TRIAL REGISTRATION: ClinicalTrials.gov NCT03268902.


Asunto(s)
Antiinfecciosos/farmacología , Desarrollo Infantil/efectos de los fármacos , Niacinamida/farmacología , Adulto , Antiinfecciosos/administración & dosificación , Azitromicina/administración & dosificación , Azitromicina/farmacología , Método Doble Ciego , Esquema de Medicación , Femenino , Trastornos del Crecimiento/prevención & control , Humanos , Lactante , Recién Nacido , Parasitosis Intestinales/prevención & control , Niacinamida/administración & dosificación , Nitrocompuestos/administración & dosificación , Nitrocompuestos/farmacología , Embarazo , Tanzanía , Tiazoles/administración & dosificación , Tiazoles/farmacología
8.
Parasit Vectors ; 14(1): 416, 2021 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-34419129

RESUMEN

BACKGROUND: We evaluated the efficiency of an ex vivo feeding technique using a silicone membrane-based feeding chamber to (i) assess the anti-feeding and acaricidal efficacy of a spot-on combination of dinotefuran, pyriproxyfen and permethrin (DPP, Vectra® 3D) against adult Ixodes scapularis and Ixodes ricinus ticks, and to (ii) explore its effect on blocking the acquisition of Borrelia burgdorferi sensu stricto. METHODS: Eight purpose-bred dogs were randomly allocated to two equal-size groups based on body weight assessed on day 2. DPP was administered topically, as spot-on, to four dogs on day 0. Hair from the eight dogs was collected individually by brushing the whole body on days 2, 7, 14, 21, 28 and 35. On each day of hair collection, 0.05 g of sampled hair was applied on the membrane corresponding to each feeding unit (FU). Seventy-two FU were each seeded with 30 adults of I. scapularis (n = 24 FU) or I. ricinus ticks (n = 48 FU). Bovine blood spiked with B. burgdorferi sensu stricto (strain B31) was added into each unit and changed every 12 h for 4 days. Tick mortality was assessed 1 h after seeding. One additional hour of incubation was added for live/moribund specimens and reassessed for viability. All remaining live/moribund ticks were left in the feeders and tick engorgement status was recorded at 96 h after seeding, and the uptake of B. burgdorferi s.s. was examined in the collected ticks by applying quantitative real-time PCR. RESULTS: Exposure to DPP-treated hair was 100% effective in blocking B. burgdorferi s.s. acquisition. The anti-feeding efficacy remained stable (100%) against both Ixodes species throughout the study. The acaricidal efficacy of DPP evaluated at 1 and 2 h after exposure was 100% throughout the study for I. ricinus, except the 1-h assessment on day 28 (95.9%) and day 35 (95.3%). The 1-h assessment of acaricidal efficacy was 100% at all time points for I. scapularis. CONCLUSIONS: The ex vivo feeding system developed here demonstrated a protective effect of DPP against the acquisition of B. burgdorferi without exposing the animals to the vectors or to the pathogen.


Asunto(s)
Enfermedades de los Perros/prevención & control , Guanidinas/administración & dosificación , Insecticidas/administración & dosificación , Ixodes/efectos de los fármacos , Enfermedad de Lyme/prevención & control , Neonicotinoides/administración & dosificación , Nitrocompuestos/administración & dosificación , Permetrina/administración & dosificación , Piridinas/administración & dosificación , Administración Tópica , Animales , Borrelia burgdorferi/fisiología , Enfermedades de los Perros/microbiología , Perros , Combinación de Medicamentos , Conducta Alimentaria , Femenino , Ixodes/clasificación , Ixodes/microbiología , Enfermedad de Lyme/transmisión , Masculino
9.
J Chromatogr A ; 1652: 462350, 2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-34198103

RESUMEN

This study aimed to (i) develop a sensitive method for simultaneous detection and quantification of imidacloprid (IMI) and seven of its metabolites in tissue specimens, and to (ii) determine the biodistribution of the IMI compounds in tissues of C57BL/6J male mice; after exposure to 0.6 mg/kg bw/day of IMI (10% of no observable adverse effect level of IMI) through a powdered diet for 24 weeks. We successfully developed a method which was accurate (recoveries were ≥ 70% for most compounds), sensitive (LODs ≤ 0.47 ng/mL and LOQs ≤ 1.43 ng/mL were recorded for all detected compounds, R2 ≥ 0.99) and precise (RSDs ≤ 20%) for routine analysis of IMI and seven of its metabolites in blood and various tissue matrices. After bio-distributional analysis, IMI and five of its metabolites were detected in mice. Brain, testis, lung, kidney, inguinal white adipose tissue and gonadal white adipose tissue mainly accumulated IMI, blood and mesenteric white adipose tissue mainly accumulated IMI-olefin; liver mainly accumulated desnitro-IMI; pancreas predominately accumulated 4-hydroxy-IMI. The desnitro-dehydro-IMI and the desnitro-IMI metabolites recorded tissue-blood concentration ratios ≥ 1.0 for testis, brain, lung and kidney. The cumulative levels of the six detected IMI compounds (Σ6 IMI compounds) were found in the decreasing order: blood > testis > brain > kidney > lung > iWAT > gWAT > mWAT > liver > pancreas. Altogether, this study provided essential data needed for effective mechanistic elucidation of compound-specific adverse outcomes associated with chronic exposures to IMI in mammalian species.


Asunto(s)
Cromatografía Liquida , Insecticidas/farmacocinética , Neonicotinoides/farmacocinética , Nitrocompuestos/farmacocinética , Espectrometría de Masas en Tándem , Tejido Adiposo Blanco/metabolismo , Animales , Encéfalo/metabolismo , Insecticidas/administración & dosificación , Insecticidas/análisis , Insecticidas/sangre , Riñón/metabolismo , Hígado/metabolismo , Masculino , Ratones Endogámicos C57BL , Neonicotinoides/administración & dosificación , Neonicotinoides/análisis , Neonicotinoides/sangre , Nitrocompuestos/administración & dosificación , Nitrocompuestos/análisis , Nitrocompuestos/sangre , Testículo/metabolismo , Distribución Tisular
10.
Artículo en Inglés | MEDLINE | ID: mdl-34087391

RESUMEN

Huntington's disease (HD) is characterized by abnormal involuntary movements together with cognitive impairment and disrupted mood changes. 3-nitropropionic acid (3-NP) is one of the chemo-toxic models used to address the striatal neurotoxicity pattern encountered in HD. This study aims to explain the neuroprotective effect of nano-formulated ivabradine (nano IVA) in enhancing behavioral changes related to 3-NP model and to identify the involvement of ras homolog enriched striatum (Rhes)/mammalian target of rapamycin (m-Tor) mediated autophagy pathway. Rats were divided into 6 groups, the first 3 groups received saline (control), ivabradine (IVA), nano IVA respectively, the fourth received a daily dose of 3-NP (20 mg/kg, s.c) for 2 weeks, the fifth received 3-NP + IVA (1 mg/kg, into the tail vein, every other day for 1 week) and the last group received 3-NP + nano IVA (1 mg/kg, i.v, every other day for 1 week). Interestingly, nano IVA reversed motor disabilities, improved memory function and overcame the psychiatric changes. It boosted expression of autophagy markers combined with down regulation of Rhes, m-Tor and b-cell lymphoma 2 protein levels. Also, it restored the normal level of neurotransmitters and myocardial function related-proteins. Histopathological examination revealed a preserved striatal structure with decreased number of darkly-degenerated neurons. In conclusion, the outcomes of this study provide a well-recognized clue for the promising neuroprotective effect of IVA and the implication of autophagy and Rhes/m-Tor pathways in the 3-NP induced HD and highlight the fact that nano formulations of IVA would be an auspicious approach in HD therapy.


Asunto(s)
Fármacos Cardiovasculares/administración & dosificación , Enfermedad de Huntington/inducido químicamente , Ivabradina/administración & dosificación , Fármacos Neuroprotectores/administración & dosificación , Serina-Treonina Quinasas TOR/metabolismo , Animales , Autofagia , Cuerpo Estriado/metabolismo , Modelos Animales de Enfermedad , Enfermedad de Huntington/metabolismo , Masculino , Sistema de Administración de Fármacos con Nanopartículas , Nitrocompuestos/administración & dosificación , Propionatos/administración & dosificación , Ratas
11.
J Drug Target ; 29(9): 998-1003, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34016002

RESUMEN

Vascular normalisation refers to a 'remodeling' of the dysfunctional tumour capillary network, which regresses under the influence of anti-VEGF treatment, resulting in improved blood flow and oxygenation. RRx-001 is an anti-CD47-SIRPα small molecule with vascular normalising properties under investigation in clinical trials for the treatment of glioblastoma, brain metastases, lung cancer and colorectal cancer, with FDA Orphan Drug Designation in glioblastoma and other tumour types. This study investigated whether the improved oxygenation and perfusion that has been previously observed with RRx-001 both preclinically and clinically in the context of a brain metastasis trial was correlated with increased penetration and accumulation of the cytotoxic chemotherapies, irinotecan and temozolomide, in orthotopically implanted gliomas, priming tumours for improved response. The experiments demonstrate that administration of RRx-001 prior to temozolomide or irinotecan results in significantly increased uptake of irinotecan and temozolomide in orthotopic glioma tumours. Since the success of chemotherapy in the brain (and outside of it) is limited by subtherapeutic tumoral drug concentrations, vascular normalisation-enhanced delivery of standard cytotoxics as demonstrated with RRx-001 may mitigate or reverse clinical drug resistance and thereby improve the outcome of cancer therapy, particularly in the brain.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Azetidinas/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , Glioma/tratamiento farmacológico , Nitrocompuestos/farmacología , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Azetidinas/administración & dosificación , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Femenino , Glioma/patología , Humanos , Irinotecán/administración & dosificación , Ratones , Ratones Desnudos , Nitrocompuestos/administración & dosificación , Temozolomida/administración & dosificación , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Artículo en Inglés | MEDLINE | ID: mdl-33862234

RESUMEN

Microplastics (MPs) and pesticides are two kinds of ubiquitous pollutants that can pose a health risk to aquatic organisms. However, researches about the combined effects of MPs and pesticides are very limited. A simple combined exposure model was established in this study, adult zebrafish were exposed to 100 µg/L imidacloprid (IMI), 20 µg/L polystyrene microplastics (PS), and a combination of PS and IMI (PS + IMI) for 21 days. The results demonstrated that exposure to PS and IMI inhibited the growth of zebrafish and altered the levels of glycolipid metabolism and oxidative stress-related biochemical parameters. While gene expression analysis revealed that, compared with PS or IMI treatment group, combined exposure caused a greater change in gene expression levels involving the process of glycolipid metabolism (Gk, Hk1, Aco, PPar-α, Cpt1, Acc, Fas, PPar-γ, Apo) and inflammatory response (IL-1ß, IL-6, IL-8, TNF-α, IL-10). The results demonstrated that even combined exposure of low concentrations of PS and IMI could cause more severe hepatotoxicity in zebrafish, especially in terms of gene transcription. And more combined toxicity studies are essential for MPs and pesticides risk assessment.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Regulación de la Expresión Génica/efectos de los fármacos , Insecticidas/toxicidad , Microplásticos/toxicidad , Neonicotinoides/toxicidad , Nitrocompuestos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Quimioterapia Combinada , Insecticidas/administración & dosificación , Hígado/efectos de los fármacos , Hígado/patología , Neonicotinoides/administración & dosificación , Nitrocompuestos/administración & dosificación , ARN Mensajero/genética , ARN Mensajero/metabolismo , Pez Cebra
13.
J Med Virol ; 93(5): 3176-3183, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33590901

RESUMEN

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.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Ivermectina/uso terapéutico , Nitrocompuestos/uso terapéutico , Ribavirina/uso terapéutico , SARS-CoV-2 , Tiazoles/uso terapéutico , Zinc/uso terapéutico , Adulto , Antimetabolitos/administración & dosificación , Antimetabolitos/uso terapéutico , Antiparasitarios/administración & dosificación , Antiparasitarios/uso terapéutico , Femenino , Humanos , Ivermectina/administración & dosificación , Masculino , Nitrocompuestos/administración & dosificación , Ribavirina/administración & dosificación , Tiazoles/administración & dosificación , Oligoelementos/administración & dosificación , Oligoelementos/uso terapéutico , Zinc/administración & dosificación
14.
Expert Opin Drug Metab Toxicol ; 17(4): 355-357, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33432831

RESUMEN

Introduction: The CD47 and SIRPα checkpoint pathway has garnered much interest within the anti-cancer research community, with multiple experimental checkpoint inhibitors targeting CD47 and SIRPα in development. The use of such checkpoint inhibitors may however be limited by hematologic toxicity.Areas covered: We report on RRx-001, the first known small molecule downregulator of CD47 and SIRPα, which has shown a lack of hematologic toxicity in clinical trials.Expert opinion: RRx-001 is the first reported small molecule downregulator of CD47 and SIRPα and lacks any notable hematologic or systemic toxicity as demonstrated in clinical trials to date. Small molecule RRx-001 could be used in combination with or in place of CD47 targeting antibodies for anti-cancer treatment.


Asunto(s)
Antineoplásicos/efectos adversos , Azetidinas/efectos adversos , Nitrocompuestos/efectos adversos , Anemia/epidemiología , Anemia/etiología , Antígenos de Diferenciación/metabolismo , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Azetidinas/administración & dosificación , Azetidinas/farmacología , Antígeno CD47/metabolismo , Humanos , Nitrocompuestos/administración & dosificación , Nitrocompuestos/farmacología , Receptores Inmunológicos/metabolismo , Trombocitopenia/epidemiología , Trombocitopenia/etiología
15.
Br J Clin Pharmacol ; 87(4): 2078-2088, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33085781

RESUMEN

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been declared a global pandemic and urgent treatment and prevention strategies are needed. Nitazoxanide, an anthelmintic drug, has been shown to exhibit in vitro activity against SARS-CoV-2. The present study used physiologically based pharmacokinetic (PBPK) modelling to inform optimal doses of nitazoxanide capable of maintaining plasma and lung tizoxanide exposures above the reported SARS-CoV-2 EC90 . METHODS: A whole-body PBPK model was validated against available pharmacokinetic data for healthy individuals receiving single and multiple doses between 500 and 4000 mg with and without food. The validated model was used to predict doses expected to maintain tizoxanide plasma and lung concentrations above the EC90 in >90% of the simulated population. PopDes was used to estimate an optimal sparse sampling strategy for future clinical trials. RESULTS: The PBPK model was successfully validated against the reported human pharmacokinetics. The model predicted optimal doses of 1200 mg QID, 1600 mg TID and 2900 mg BID in the fasted state and 700 mg QID, 900 mg TID and 1400 mg BID when given with food. For BID regimens an optimal sparse sampling strategy of 0.25, 1, 3 and 12 hours post dose was estimated. CONCLUSION: The PBPK model predicted tizoxanide concentrations within doses of nitazoxanide already given to humans previously. The reported dosing strategies provide a rational basis for design of clinical trials with nitazoxanide for the treatment or prevention of SARS-CoV-2 infection. A concordant higher dose of nitazoxanide is now planned for investigation in the seamless phase I/IIa AGILE trial.


Asunto(s)
Antivirales/administración & dosificación , Tratamiento Farmacológico de COVID-19 , COVID-19/prevención & control , Reposicionamiento de Medicamentos , Modelos Biológicos , Nitrocompuestos/administración & dosificación , Tiazoles/administración & dosificación , Adulto , Antivirales/sangre , Antivirales/farmacocinética , COVID-19/sangre , Simulación por Computador , Cálculo de Dosificación de Drogas , Femenino , Humanos , Pulmón/metabolismo , Masculino , Persona de Mediana Edad , Nitrocompuestos/sangre , Nitrocompuestos/farmacocinética , Reproducibilidad de los Resultados , Tiazoles/sangre , Tiazoles/farmacocinética , Distribución Tisular , Adulto Joven
16.
Clin Toxicol (Phila) ; 59(4): 347-350, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32959700

RESUMEN

BACKGROUND: Self-poisoning with imidacloprid has been previously shown to have low toxicity in humans. Since 2007 newer formulations of Imidacloprid with unknown solvents have been introduced and the potential clinical consequences of these products have not been described. METHODS: Clinical and demographic data were prospectively collected from admissions following oral ingestion of imidacloprid from seven hospitals in Sri Lanka. Data was collected from 2002 to 2007 in an already published study. We compared this data on poisonings collected from 2010 to 2016 following the introduction of new formulations of imidacloprid. RESULTS: From 2002-2007, there were 56 patients with ingestion to imidacloprid compared to 67 patients post 2010 The median time to presentation prior to 2007 was 4 h (IQR 2.3-6.0 hrs) and post 2010 was only 2.0 hr (IQR 1.5 to 3.1 hrs). The median amount ingested was 15 ml (IQR 10.0-50.0mls) prior to 2007 and 27.5mls (IQR 5.0-71.8mls) post 2010. In both studies most patients developed non-specific symptoms including nausea, vomiting, epigastric pain and headache. However, prior to 2007 only 1.9% of the cohort required mechanical ventilation due to respiratory failure and there were no reported deaths. In contrast, post 2010; deaths occurred in 3.0% of the cohort and 6.0% required mechanical ventilation for respiratory failure. The cause of mortality was due to one case of cardiorespiratory failure and the other due to a prolonged admission complicated with lobar pneumonia leading to decompensated liver failure on the background of undiagnosed liver cirrhosis. CONCLUSION: Although acute exposure to imidacloprid is usually associated with mild non-specific symptoms, since the introduction of new formulations of imidacloprid, the toxic profile has changed with reported cases of death as well as an increase in cases requiring mechanical ventilation. The change in toxicity could be due to the solvents used in the newer formulations but also due to higher dose of imidacloprid described in our latter cohort. Further research into these solvents needs to be done and continued toxicovigilance is required.


Asunto(s)
Insecticidas/envenenamiento , Neonicotinoides/envenenamiento , Nitrocompuestos/envenenamiento , Administración Oral , Humanos , Insecticidas/administración & dosificación , Insecticidas/toxicidad , Masculino , Persona de Mediana Edad , Neonicotinoides/administración & dosificación , Neonicotinoides/toxicidad , Nitrocompuestos/administración & dosificación , Nitrocompuestos/toxicidad , Estudios Prospectivos , Respiración Artificial , Insuficiencia Respiratoria/inducido químicamente , Insuficiencia Respiratoria/terapia , Sri Lanka
17.
Chem Biol Interact ; 338: 109287, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33129804

RESUMEN

Imidacloprid is a neonicotinoid insecticide that acts selectively as an agonist on insect nicotinic acetylcholine receptors. It is used for crop protection worldwide, as well as for non-agricultural uses. Imidacloprid systemic accumulation in food is an important source of imidacloprid exposure. Due to the undisputable need for investigations of imidacloprid toxicity in non-target species, we evaluated the effects of a 28-day oral exposure to low doses of imidacloprid (0.06 mg/kg b. w./day, 0.8 mg/kg b. w./day and 2.25 mg/kg b. w./day) on cholinesterase activity, oxidative stress responses and primary DNA damage in the blood and brain tissue of male Wistar rats. Exposure to imidacloprid did not cause significant changes in total cholinesterase, acetylcholinesterase and butyrylcholinesterase activities in plasma and brain tissue. Reactive oxygen species levels and lipid peroxidation increased significantly in the plasma of rats treated with the lowest dose of imidacloprid. Activities of glutathione-peroxidase in plasma and brain and superoxide dismutase in erythrocytes increased significantly at the highest applied dose. High performance liquid chromatography with UV diode array detector revealed the presence of imidacloprid in the plasma of all the treated animals and in the brain of the animals treated with the two higher doses. The alkaline comet assay results showed significant peripheral blood leukocyte damage at the lowest dose of imidacloprid and dose-dependent brain cell DNA damage. Oral 28-day exposure to low doses of imidacloprid in rats resulted in detectable levels of imidacloprid in plasma and brain tissue that directly induced DNA damage, particularly in brain tissue, with slight changes in plasma oxidative stress parameters.


Asunto(s)
Acetilcolinesterasa/sangre , Encéfalo/enzimología , Encéfalo/patología , Butirilcolinesterasa/sangre , Daño del ADN , Neonicotinoides/administración & dosificación , Nitrocompuestos/administración & dosificación , Estrés Oxidativo , Acetilcolinesterasa/metabolismo , Administración Oral , Animales , Biomarcadores/metabolismo , Peso Corporal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Butirilcolinesterasa/metabolismo , Catalasa/metabolismo , Ensayo Cometa , Glutatión/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Tamaño de los Órganos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismo
18.
World J Urol ; 39(4): 1187-1194, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32488358

RESUMEN

PURPOSE: Nitazoxanide (NTZ) has shown a promising antitumoral effect, the current study compared the anti-neoplastic effects of intravesical NTZ and BCG plus NTZ in NMIBC animal model. METHODS: 30 rats, Fisher 344 were instilled with 4 intravesical doses of 1.5 mg/kg of N-methyl-N-nitrosourea (MNU) every 15 days for BC induction. The animals were divided into 3 groups (Group BCG 106 UFC - 1 mg of BCG; Group NTZ - 300 mg/kg of NTZ; Group NTZ + BCG - simultaneous treatment of BCG and NTZ) and received weekly intravesical treatment for 6 consecutive weeks. Animals were submitted to ultrasound imaging and euthanasia, their bladders were collected and histopathological, immunohistochemical tests (ki67 e c-Myc) and Western Blotting (PI3K, mTOR, and p-4E-BP) were performed. RESULTS: Histopathological tests showed 66.67%, 62.5% and 37.5% incidence of BC in animals treated with BCG, NTZ, and NTZ + BCG, respectively. Nuclear positivity for ki-67 in BC animals were 12.4% (IC 10.1-14.6%), 13.2% (IC 10.5-15.9%) and 8.8% (IC 6.0-11.6%) in BCG, NTZ and NTZ + BCG group, respectively (p = 0.063). Between animals with carcinoma, c-Myc strong positive was 40.10% in NTZ, 32.2% in BCG and 19.90% in the NTZ + BCG group (p < 0.001). Blotting has shown mTOR (p = 0.0473) and PI3K inhibition (p = 0.0349) in the presence of BCG, added to 4-EBP inhibition in the presence of NTZ (p = 0.0004). CONCLUSIONS: Results show the possible synergy between the gold standard BC treatment BCG and NTZ, in which multiple targets inhibition such as c-Myc and downstream mTOR, p-4E-BP and PI3K might play a role.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Vacuna BCG/administración & dosificación , Nitrocompuestos/administración & dosificación , Tiazoles/administración & dosificación , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Administración Intravesical , Animales , Combinación de Medicamentos , Femenino , Ratas , Ratas Endogámicas F344
19.
Acta Trop ; 213: 105755, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33188747

RESUMEN

PURPOSE: The aim of this study is to determine the prevalence of intestinal helminths and protozoa in patients with ulcerative colitis (UC) and to estimate the influence of the anti-parasitic therapy on the course of the disease. METHODS: The study was conducted at the Research Institute of Epidemiology, Microbiology and Infectious Diseases and Coloproctology Department of the Republic Clinical Hospital №1 of the Ministry of Health of the Republic of Uzbekistan. One hundred UC patients and 200 healthy individuals were examined by triple coproscopy. Additionally, 20, 25 and 22 UC patients with Blastocystis infection were treated with nitazoxanide (1.0 g/day), mesalazine (1.5-2 g/day) or a combination of nitazoxanide (1.0 g/day) and mesalazine (≥1.5-2 g/day) for 14 consecutive days, respectively. Parasitological, clinical and endoscopic examinations were conducted before therapy, immediately after and 6 and 12 weeks after therapy completion. RESULTS: The overall prevalence of helminths in UC patients and control individuals was not significantly different: 14±3.4% and 8.5±1.9%, respectively (OR: 1.7524; 95% CI: 0.8258 to 3.7186; P=0.1). Giardia lamblia was the most prevalent parasite in both groups, but the difference compared to the control was insignificant (OR: 0.4565; 95% CI: 0.2020 to 1.0318; P=0.05). A significantly higher prevalence of Blastocystis sp., Chilomastix mesnili and Iodamoeba butschlii in UC patients compared to control individuals was found (P<0.0005): 65.0%, 14.0% and 22.0%, respectively. During all follow-up periods, the clinical response and clinical remission were not statistically different between the groups (P>0.05). Mucosal healing immediately and 6 weeks after therapy with a combination of nitazoxanide with mesalazine was significantly better than with a monotherapy of nitazoxanide, respectively (P<0.05). UC patients treated with a combination of nitazoxanide with mesalazine showed better mucosal healing than in patients treated with a monotherapy of mesalazine (P>0.05). CONCLUSIONS: Diagnosis of Blastocystis sp. should be introduced in the complex examination of UC patients. Further clinical studies are necessary for assessment of the efficiency of anti-Blastocystis therapy in UC patients.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Antiparasitarios/uso terapéutico , Infecciones por Blastocystis/tratamiento farmacológico , Blastocystis/aislamiento & purificación , Colitis Ulcerosa/tratamiento farmacológico , Giardia lamblia/aislamiento & purificación , Intestinos/parasitología , Adulto , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Antiparasitarios/administración & dosificación , Blastocystis/efectos de los fármacos , Infecciones por Blastocystis/parasitología , Colitis Ulcerosa/parasitología , Quimioterapia Combinada , Femenino , Giardia lamblia/efectos de los fármacos , Humanos , Masculino , Mesalamina/administración & dosificación , Mesalamina/uso terapéutico , Persona de Mediana Edad , Nitrocompuestos/administración & dosificación , Nitrocompuestos/uso terapéutico , Prevalencia , Tiazoles/administración & dosificación , Tiazoles/uso terapéutico , Resultado del Tratamiento , Adulto Joven
20.
Curr Gastroenterol Rep ; 22(12): 59, 2020 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-33188441

RESUMEN

PURPOSE OF REVIEW: The aim of this review is to evaluate emerging, novel therapies for the prevention of post-ERCP pancreatitis. RECENT FINDINGS: Rectal indomethacin reduces the risk of pancreatitis in low- and average-risk patients, who comprise the majority of patients undergoing ERCP. An 8-h protocol of aggressive lactated Ringer's reduces the risk of pancreatitis in average-risk patients. Sublingual nitrate may provide additional benefit to rectal NSAIDs in preventing PEP. A tacrolimus trough > 2.5 ng/mL was recently shown to be associated with a lower risk of PEP in liver transplant patients undergoing ERCP. Routine usage of rectal indomethacin in all patients undergoing ERCP reduces the risk of PEP. Pancreatic-duct stents reduce the risk of PEP in high-risk patients. There is emerging data that aggressive hydration with lactated Ringer's and nitrates may further reduce PEP. Tacrolimus is a promising potential agent to prevent PEP but needs further clinical study.


Asunto(s)
Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Pancreatitis/prevención & control , Administración Rectal , Antiinflamatorios no Esteroideos/administración & dosificación , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/sangre , Indometacina/administración & dosificación , Nitrocompuestos/administración & dosificación , Conductos Pancreáticos/cirugía , Pancreatitis/sangre , Pancreatitis/etiología , Lactato de Ringer/administración & dosificación , Stents , Tacrolimus/administración & dosificación , Tacrolimus/sangre
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