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1.
Chem Res Toxicol ; 34(3): 793-803, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33486946

RESUMEN

Formation of DNA adducts is a key event during carcinogenesis. DNA adducts, if not repaired properly, can lead to mutations and cancer. DNA adducts have been frequently used as biomarkers to evaluate chemical exposure. Vinyl acetate monomer (VAM) is widely used in the manufacture of various industrial polymers. Previous studies have documented that VAM induced nasal tumors in rodents exposed to high exposure levels of VAM. VAM is metabolized by carboxylesterase to acetaldehyde (AA), which subsequently results in DNA adducts. However, AA is also an endogenous metabolite in living cells, which impedes accurate assessment of the contribution of VAM exposure under the substantial endogenous background. To address this challenge, we exposed rats to stable isotope labeled [13C2]-VAM at 50, 200, and 400 ppm through inhalation for 6 h, followed by DNA adduct analysis in nasal respiratory and olfactory epithelia with highly sensitive mass spectrometry. Our results show that exogenous N2-ethyl-dG adducts were present in all rats exposed to [13C2]-VAM, with over 2-fold higher DNA adducts in nasal respiratory epithelium than olfactory epithelium. Our data also show that N2-ethyl-dG is a more sensitive biomarker to assess VAM exposure than 1,N2-propano-dG adducts. Moreover, a very low amount of exogenous N2-ethyl-dG adducts were detected in peripheral blood mononuclear cell samples of exposed rats, suggesting that only an extremely small percentage of [13C2]-VAM or its metabolite may enter into systemic circulation to potentially damage tissues beyond nasal epithelium. Furthermore, exogenous N2-ethyl-dG DNA adducts undergo rapid repair or spontaneous loss in nasal epithelium of exposed rats. Taken together, the results presented herein provide novel quantitative data and lay the foundation for future studies to improve risk assessment of VAM.


Asunto(s)
Aductos de ADN/análisis , Compuestos de Vinilo/farmacología , Administración por Inhalación , Animales , Cromatografía Líquida de Alta Presión , Aductos de ADN/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Espectrometría de Masas en Tándem , Compuestos de Vinilo/administración & dosificación
2.
Lipids ; 56(2): 167-180, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32989804

RESUMEN

Ethanolamine plasmalogen (PlsEtn), a sub-class of ethanolamine glycerophospholipids (EtnGpl), is a universal phospholipid in mammalian membranes. Several researchers are interested in the relationship between colon carcinogenesis and colon PlsEtn levels. Here, we evaluated the functional role of dietary purified EtnGpl from the ascidian muscle (87.3 mol% PlsEtn in EtnGpl) and porcine liver (7.2 mol% PlsEtn in EtnGpl) in 1,2-dimethylhydrazine (DMH)-induced aberrant crypt foci (ACF) in vivo, and elucidated the possible underlying mechanisms behind it. Dietary EtnGpl-suppressed DMH-induced aberrant crypt with one foci (AC1) and total ACF formation (P < 0.05). ACF suppression by dietary ascidian muscle EtnGpl was higher compared with dietary porcine liver EtnGpl. Additionally, dietary EtnGpl decreased DMH-induced oxidative damage, overproduction of TNF-α, and expression of apoptosis-related proteins in the colon mucosa. The effect of dietary ascidian muscle EtnGpl showed superiority compared with dietary porcine liver EtnGpl. Our results demonstrate the mechanisms by which dietary PlsEtn suppress ACF formation and apoptosis. Dietary PlsEtn attained this suppression by reducing colon inflammation and oxidative stress hence a reduction in DMH-induced intestinal impairment. These findings provide new insights about the functional role of dietary PlsEtn during colon carcinogenesis.


Asunto(s)
Focos de Criptas Aberrantes/metabolismo , Carcinogénesis/efectos de los fármacos , Colon/efectos de los fármacos , Inflamación/tratamiento farmacológico , Plasmalógenos/farmacología , Compuestos de Vinilo/farmacología , 1,2-Dimetilhidrazina/antagonistas & inhibidores , Focos de Criptas Aberrantes/inducido químicamente , Animales , Apoptosis/efectos de los fármacos , Carcinogénesis/metabolismo , Colon/metabolismo , Colon/patología , Exposición Dietética , Inflamación/inducido químicamente , Inflamación/metabolismo , Hígado/química , Músculos/química , Estrés Oxidativo/efectos de los fármacos , Plasmalógenos/administración & dosificación , Porcinos , Urocordados , Compuestos de Vinilo/administración & dosificación
3.
Life Sci ; 262: 118543, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33038381

RESUMEN

AIMS: Premature ovarian failure (POF) is a phenomenon in which the ovaries fail before the age of 40 years. Prior research has used a wide range of mouse models designed to reflect different causes of POF, including genetic factors, iatrogenic factors, and immune factors. The current study employed a mouse model of POF induced by 4-vinylcyclohexene diepoxide (VCD). VCD can specifically kill primordial and primary ovarian follicles, which destroys the follicular reserve and causes POF. The current study sought to specify and extend the applications of this model by examining the effect of timing and VCD dose and by exploring the effect of the model on systems outside of the ovaries. MATERIALS AND METHODS: A VCD-induced mouse model of POF was constructed using established methods (VCD injected continuously at a concentration of 160 mg/kg for 15 days). Evidence for a graded effect of VCD was observed using a range of concentrations, and the best windows for examining VCD's effects on follicles and associated tissues were identified. KEY FINDINGS: The mouse model used here successfully simulated two common complications of POF - emotional changes and decreased bone density. The model's application was then extended to examine the links between disease and intestinal microorganisms, and evidence was found linking POF to the reproductively relevant composition of the gut microbiota. SIGNIFICANCE: These findings provide novel methodological guidance for future research, and they significantly extend the applications and scope of VCD-induced POF mouse models.


Asunto(s)
Modelos Animales de Enfermedad , Microbioma Gastrointestinal/fisiología , Folículo Ovárico/patología , Insuficiencia Ovárica Primaria/fisiopatología , Animales , Densidad Ósea/fisiología , Ciclohexenos/administración & dosificación , Ciclohexenos/toxicidad , Relación Dosis-Respuesta a Droga , Emociones/fisiología , Femenino , Ratones , Ratones Endogámicos C57BL , Insuficiencia Ovárica Primaria/complicaciones , Insuficiencia Ovárica Primaria/microbiología , Compuestos de Vinilo/administración & dosificación , Compuestos de Vinilo/toxicidad
4.
Neurotherapeutics ; 17(3): 1142-1152, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32394330

RESUMEN

The Nrf2 transcription factor is a key regulator of redox reactions and considered the main target for the multiple sclerosis (MS) drug dimethyl fumarate (DMF). However, exploration of additional Nrf2-activating compounds is motivated, since DMF displays significant off-target effects and has a relatively poor penetrance to the central nervous system (CNS). We de novo synthesized eight vinyl sulfone and sulfoximine compounds (CH-1-CH-8) and evaluated their capacity to activate the transcription factors Nrf2, NFκB, and HIF1 in comparison with DMF using the pTRAF platform. The novel sulfoximine CH-3 was the most promising candidate and selected for further comparison in vivo and later an experimental model for traumatic brain injury (TBI). CH-3 and DMF displayed comparable capacity to activate Nrf2 and downstream transcripts in vitro, but with less off-target effects on HIF1 from CH-3. This was verified in cultured microglia and oligodendrocytes (OLs) and subsequently in vivo in rats. Following TBI, DMF lowered the number of leukocytes in blood and also decreased axonal degeneration. CH-3 preserved or increased the number of pre-myelinating OL. While both CH-3 and DMF activated Nrf2, CH-3 showed less off-target effects and displayed more selective OL associated effects. Further studies with Nrf2-acting compounds are promising candidates to explore potential myelin protective or regenerative effects in demyelinating disorders.


Asunto(s)
Dimetilfumarato/administración & dosificación , Dimetilfumarato/química , Factor 2 Relacionado con NF-E2/metabolismo , Sulfonas/administración & dosificación , Sulfonas/síntesis química , Animales , Células HEK293 , Humanos , Factor 2 Relacionado con NF-E2/agonistas , Ratas , Compuestos de Vinilo/administración & dosificación , Compuestos de Vinilo/síntesis química
5.
Toxins (Basel) ; 12(3)2020 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-32164382

RESUMEN

High serum levels of microbiota-derived uremic toxins, indoxyl sulfate (IS) and p-cresyl sulfate (PCS), are associated with chronic kidney disease (CKD) progression and cardiovascular complications. IS and PCS cannot be efficiently removed by conventional hemodialysis (HD), due to their high binding affinity for albumin. This study evaluates the efficacy of a divinylbenzene-polyvinylpyrrolidone (DVB-PVP) cartridge and a synbiotic to reduce uremic toxins in HD patients. First, the in vitro efficacy of DVB-PVP in adsorbing IS and PCS was evaluated. Second, a randomized, placebo-controlled pilot study in HD patients was carried out to establish whether the administration of a synbiotic, either individually and in association with DVB-PVP-HD, could reduce the production of uremic toxins. In vitro data showed that DVB-PVP resin removed a mean of 56% PCS and around 54% IS, after 6 h of perfusion. While, in the in vivo study, the DVB-PVP cartridge showed its adsorbing efficacy only for IS plasma levels. The combination of synbiotic treatment with DVB-PVP HD decreased IS and PCS both at pre- and post-dialysis levels. In conclusion, this study provides the first line of evidence on the synergistic action of gut microbiota modulation and an innovative absorption-based approach in HD patients, aimed at reducing plasma levels of IS and PCS.


Asunto(s)
Cresoles/sangre , Indicán/sangre , Povidona/administración & dosificación , Diálisis Renal , Ésteres del Ácido Sulfúrico/sangre , Simbióticos/administración & dosificación , Compuestos de Vinilo/administración & dosificación , Adsorción , Adulto , Cresoles/química , Femenino , Humanos , Indicán/química , Masculino , Persona de Mediana Edad , Proyectos Piloto , Povidona/química , Ésteres del Ácido Sulfúrico/química , Compuestos de Vinilo/química
6.
Eur J Pharm Sci ; 127: 60-70, 2019 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-30343153

RESUMEN

In this study, novel ritonavir solid dispersion (RTV SD) formulations were prepared with copovidone (PVPVA 64) and optimized plasticizers via hot-melt extrusion (HME) at different extrusion temperature to evaluate the effect of plasticizers on the process of HME. The optimized drug-loading content of RTV SD formulations was around 15% and RTV was converted to the amorphous state and integrated through physical interactions (possibly hydrogen bonding) with the polymeric carrier. Using Span 20 or HSPC as plasticizer, the HME extrusion temperature of RTV SD formulations suggested a decrease of 10 °C or 20 °C. Furthermore, the in vitro release and the in vivo pharmacokinetics analyses both showed that RTV SD formulations using Span 20 or HSPC as plasticizer possessed better release profiles and bioavailability over RTV bulk powder but showed equal physicochemical characteristics compared to RTV SD formulations without plasticizer. According to the increased drug solubility, enhanced dissolution profiles, superior bioavailability, but decreased extrusion temperature in HME process, the RTV SD formulation using HSPC as plasticizer could be potentially applied in the clinic as an efficient drug delivery system, and HSPC is recommended as an efficient plasticizer for manufacturing RTV SD formulations via HME.


Asunto(s)
Inhibidores de la Proteasa del VIH , Plastificantes , Pirrolidinas , Ritonavir , Compuestos de Vinilo , Animales , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Inhibidores de la Proteasa del VIH/administración & dosificación , Inhibidores de la Proteasa del VIH/química , Inhibidores de la Proteasa del VIH/farmacocinética , Masculino , Plastificantes/administración & dosificación , Plastificantes/química , Plastificantes/farmacocinética , Pirrolidinas/administración & dosificación , Pirrolidinas/química , Pirrolidinas/farmacocinética , Ratas Sprague-Dawley , Ritonavir/administración & dosificación , Ritonavir/química , Ritonavir/farmacocinética , Solubilidad , Compuestos de Vinilo/administración & dosificación , Compuestos de Vinilo/química , Compuestos de Vinilo/farmacocinética
7.
Artículo en Inglés | MEDLINE | ID: mdl-30467537

RESUMEN

Vibrio campbellii is a major pathogen in aquaculture. It is a causative agent of the so-called "luminescent vibriosis," a life-threatening condition caused by bioluminescent Vibrio spp. that often involves mass mortality of farmed shrimps. The emergence of multidrug resistant Vibrio strains raises a concern and poses a challenge for the treatment of this infection in the coming years. Inhibition of bacterial cell-to-cell communication or quorum sensing (QS) has been proposed as an alternative to antibiotic therapies. Aiming to identify novel QS disruptors, the 9H-fluroen-9yl vinyl ether derivative SAM461 was found to thwart V. campbellii bioluminescence, a QS-regulated phenotype. Phenotypic and gene expression analyses revealed, however, that the mode of action of SAM461 was unrelated to QS inhibition. Further evaluation with purified Vibrio fischeri and NanoLuc luciferases revealed enzymatic inhibition at micromolar concentrations. In silico analysis by molecular docking suggested binding of SAM461 in the active site cavities of both luciferase enzymes. Subsequent in vivo testing of SAM461 with gnotobiotic Artemia franciscana nauplii demonstrated naupliar protection against V. campbellii infection at low micromolar concentrations. Taken together, these findings suggest that suppression of luciferase activity could constitute a novel paradigm in the development of alternative anti-infective chemotherapies against luminescent vibriosis, and pave the ground for the chemical synthesis and biological characterization of derivatives with promising antimicrobial prospects.


Asunto(s)
Antibacterianos/administración & dosificación , Artemia/microbiología , Luciferasas de la Bacteria/antagonistas & inhibidores , Sustancias Luminiscentes/metabolismo , Vibriosis/veterinaria , Vibrio/efectos de los fármacos , Animales , Fluorenos/administración & dosificación , Simulación del Acoplamiento Molecular , Vibriosis/prevención & control , Compuestos de Vinilo/administración & dosificación
8.
Biomater Sci ; 6(9): 2342-2359, 2018 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-30019048

RESUMEN

The purpose of this study was to prepare an electrically conducting poly[2-methoxy-5-(2-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) based nanofibrous scaffold and to investigate the synergetic effect of nanofibre structure and electrical stimulation on neuronal growth for possible use in nerve repair. Nanofibres were produced by electrospinning of blended MEH-PPV with polycaprolactone (PCL) at a ratio of 20 : 80, 40 : 60, 50 : 50 and 60 : 40 (v/v). A better electrical conductivity was achieved by using core-sheath structured nanofibres of PCL (core) and MEH-PPV (sheath) produced using the coaxial electrospinning technique. The highest electrical conductivity was observed in the core-sheath nanofibres, while it increased with increasing concentration of MEH-PPV for the blended electrospun nanofibres. The biocompatibility of the electrospun nanofibres was confirmed by MTS and live-dead staining assays using 3T3 fibroblasts and a neuronal rat pheochromocytoma (PC12) cell line. Beta (III) tubulin immunochemistry showed that PC12 cells differentiated into sympathetic neurons on these porous and stiffer electrospun nanofibres coated with collagen I. Improved cell morphology and attachment on the collagen I coated electrospun meshes has been confirmed by SEM analysis. Significant enhancement in neurite formation and neurite outgrowth of PC12 cells on the conductive scaffolds under electrical potential of 500 mV cm-1 for 2 h day-1 suggests the potential use of these scaffolds for nerve repair.


Asunto(s)
Nanofibras/química , Poliésteres/química , Polímeros/química , Compuestos de Vinilo/química , Neoplasias de las Glándulas Suprarrenales/metabolismo , Animales , Adhesión Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Estabilidad de Medicamentos , Conductividad Eléctrica , Estimulación Eléctrica , Ratones , Células 3T3 NIH , Nanofibras/administración & dosificación , Células PC12 , Feocromocitoma/metabolismo , Poliésteres/administración & dosificación , Polímeros/administración & dosificación , Ratas , Tubulina (Proteína)/metabolismo , Compuestos de Vinilo/administración & dosificación
9.
Mol Cell Endocrinol ; 476: 139-147, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-29738870

RESUMEN

Loss of ovarian function has important effects on neurotransmitter production and release with corresponding effects on cognitive performance. To date, there has been little direct comparison of the effects of surgical and transitional menopause on neurotransmitter pathways in the brain. In this study, effects on monoamines, monoamine metabolites, and the amino acids tryptophan (TRP) and tyrosine (TYR) were evaluated in adult ovariectomized (OVX) rats and in rats that underwent selective and gradual ovarian follicle depletion by daily injection of 4-vinylcyclohexene-diepoxide (VCD). Tissues from the hippocampus (HPC), frontal cortex (FCX), and striatum (STR) were dissected and analyzed at 1- and 6-weeks following OVX or VCD treatments. Tissues from gonadally intact rats were collected at proestrus and diestrus to represent neurochemical levels during natural states of high and low estrogens. In gonadally intact rats, higher levels of serotonin (5-HT) were detected at proestrus than at diestrus in the FCX. In addition, the ratio of 5-hydroxyindoleacetic acid (5-HIAA)/5HT in the FCX and HPC was lower at proestrus than at diestrus, suggesting an effect on 5-HT turnover in these regions. No other significant differences between proestrus and diestrus were observed. In OVX- and VCD-treated rats, changes were observed which were both brain region- and time point-dependent. In the HPC levels of norepinephrine, 5-HIAA, TRP and TYR were significantly reduced at 1 week, but not 6 weeks, in both OVX and VCD-treated rats relative to proestrus and diestrus. In the FCX, dopamine levels were elevated at 6 weeks after OVX relative to diestrus. A similar trend was observed at 1 week (but not 6 weeks) following VCD treatment. In the STR, norepinephrine levels were elevated at 1 week following OVX, and HVA levels were elevated at 1 week, but not 6 weeks, following VCD treatment, relative to proestrus and diestrus. Collectively, these data provide the first comprehensive analysis comparing the effects of two models of menopause on multiple neuroendocrine endpoints in the brain. These effects likely contribute to effects of surgical and transitional menopause on brain function and cognitive performance that have been reported.


Asunto(s)
Aminoácidos/metabolismo , Monoaminas Biogénicas/metabolismo , Encéfalo/metabolismo , Menopausia/metabolismo , Ovariectomía , Animales , Ciclohexenos/administración & dosificación , Ciclo Estral/efectos de los fármacos , Femenino , Hipocampo/metabolismo , Hormonas/sangre , Menopausia/efectos de los fármacos , Neostriado/metabolismo , Corteza Prefrontal/metabolismo , Ratas Sprague-Dawley , Compuestos de Vinilo/administración & dosificación
10.
Eur J Pharm Sci ; 119: 208-218, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29679707

RESUMEN

Posaconazole (PCZ) and benznidazole (BNZ) are known to show synergetic effect in treating the acute and chronic phases of Chagas disease, a neglected parasitic disease. However, as both compounds are poorly water soluble, the development of amorphous solid dispersions (ASDs) of a PCZ/BNZ fixed-dose combination in a water-soluble polymer becomes an attractive option to increase their apparent solubility and dissolution rate, potentially improving their oral bioavailability. The initial approach was to explore solvent evaporated solid dispertion (SD) systems for a PCZ/BNZ 50:50 (wt%) combination at several total drug loading levels (from SD with 10% to 50% drug loading) in water-soluble carriers, including polyvinylpyrrolidone (PVP K-30) and vinylpyrrolidone-vinyl acetate copolymer (PVPVA 64). Based on comparison of non-sink in vitro dissolution performance, ASD systems based on PVPVA was identified as the most effective carrier for a 50:50 (w/w %) fixed-dose combination of PCZ/BNZ to increase their apparent solubility and dissolution rate, mainly at 10% drug loading, which shows more expressive values of area under the curve (AUC) (7336.04 ±â€¯3.77 min.µL/mL for PCZ and 15,795.02 ±â€¯7.29 min.µL/mL for BNZ). Further characterization with polarized microscopy, powder X-ray diffraction, and thermal analysis reveals that there exists a threshold drug loading level at about 30% PCZ/BNZ, below which ASDs are obtained and above which a certain degree of crystallinity tends to result. Moreover, infrared spectroscopic analysis reveals the lack of hydrogen bonding interactions between the drugs (PCZ and BNZ) and the polymer (PVPVA) in the ASD, this is also confirmed through molecular dynamics simulations. The molecular modeling results further show that even in the absence of meaningful hydrogen bonding interactions, there is a greater tendency for PVPVA to interact preferentially with PCZ and BNZ through electrostatic interactions thereby contributing to the stability of the system. Thus, the present SD system has the advantage of presenting a fixed-dese combination of two synergistic antichagasic agents PCZ and BNZ together in amorphous form stabilized in the PVPVA matrix with enhanced dissolution, potentially improving their bioavailability and therapeutic activity in treating Chagas disease.


Asunto(s)
Portadores de Fármacos/química , Nitroimidazoles/química , Povidona/química , Pirrolidinas/química , Triazoles/química , Tripanocidas/química , Compuestos de Vinilo/química , Disponibilidad Biológica , Enfermedad de Chagas/tratamiento farmacológico , Portadores de Fármacos/administración & dosificación , Combinación de Medicamentos , Liberación de Fármacos , Sinergismo Farmacológico , Modelos Moleculares , Nitroimidazoles/administración & dosificación , Povidona/administración & dosificación , Pirrolidinas/administración & dosificación , Triazoles/administración & dosificación , Tripanocidas/administración & dosificación , Compuestos de Vinilo/administración & dosificación
11.
Drug Deliv Transl Res ; 8(1): 32-42, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28967043

RESUMEN

Three-layer thin films comprising of two polymers as substrate (ethyl cellulose and, copovidone K28) and three antihypertensive agents (hydrochlorothiazide, amiloride HCl, and carvedilol) were printed using jet dispensing technology. Two film formulations with different ethyl cellulose to copovidone K28 ratio (i.e., 90/10 and 50/50 w/w) were prepared using a three-course dispensing. The films were characterized regarding surface morphology, solid-state properties, polymer-drug interactions, drug distribution in each layer, and in vitro drug release. All the components of the films were found to be in the amorphous state apart from hydrochlorothiazide which retained its crystallinity. FT-IR spectroscopy revealed hydrogen bond interactions between carvedilol and copovidone K28. Combinations of ethyl cellulose and copovidone K28 provide suitable polymeric film substrates with the ability to modify drug release. Particularly, decreased ethyl cellulose to copovidone K28 weight ratio was found to suppress the crystallization of hydrochlorothiazide and to increase the release rate of the dispensed drugs. Jet dispensing was found to be a rapid technology for the preparation of multi-layered films that can be used as personalized formulations for the delivery of combinations of drugs.


Asunto(s)
Amilorida/química , Antihipertensivos/química , Carbazoles/química , Sistemas de Liberación de Medicamentos , Hidroclorotiazida/química , Propanolaminas/química , Tecnología Farmacéutica/métodos , Amilorida/administración & dosificación , Antihipertensivos/administración & dosificación , Carbazoles/administración & dosificación , Carvedilol , Celulosa/administración & dosificación , Celulosa/análogos & derivados , Celulosa/química , Liberación de Fármacos , Hidroclorotiazida/administración & dosificación , Propanolaminas/administración & dosificación , Pirrolidinas/administración & dosificación , Pirrolidinas/química , Compuestos de Vinilo/administración & dosificación , Compuestos de Vinilo/química
12.
Reprod Sci ; 25(7): 1093-1105, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29025323

RESUMEN

After menopause, hypertension elevates the risk of cardiac diseases, one of the major causes of women's morbidity. The gradual depletion of ovarian follicles in rats, induced by 4-vinylcyclohexene diepoxide (VCD), is a model for studying the physiology of menopause. 4-Vinylcyclohexene diepoxide treatment leads to early ovarian failure (OF) and a hormonal profile comparable to menopause in humans. We have hypothesized that OF can compromise the balance between sympathetic and parasympathetic tones of the cardiovascular system, shifting toward dominance of the former. We aimed to study the autonomic modulation of heart and blood vessels and the cardiovascular reflexes in rats presenting short-term (80 days) or long-term (180 days) OF induced by VCD. Twenty-eight-day-old Wistar rats were submitted to VCD treatment (160 mg/kg, intraperitoneally) or vehicle (control) for 15 consecutive days and experiments were conducted at 80 or 180 days after the onset of treatment. Long-term OF led to an increase in the sympathetic activity to blood vessels and an impairment in the baroreflex control of the heart, evoked by physiological changes in arterial pressure. Despite that, long-term OF did not cause hypertension during the 180 days of exposure. Short-term OF did not cause any deleterious effect on the cardiovascular parameters analyzed. These data indicate that long-term OF does not disrupt the maintenance of arterial pressure homeostasis in rats but worsens the autonomic cardiovascular control. In turn, this can lead to cardiovascular complications, especially when associated with the aging process seen during human menopause.


Asunto(s)
Sistema Nervioso Autónomo , Fenómenos Fisiológicos Cardiovasculares , Sistema Cardiovascular/inervación , Hipertensión/fisiopatología , Folículo Ovárico/efectos de los fármacos , Perimenopausia , Animales , Presión Arterial , Ciclohexenos/administración & dosificación , Femenino , Hipertensión/etiología , Modelos Animales , Ratas Wistar , Compuestos de Vinilo/administración & dosificación
13.
Regul Toxicol Pharmacol ; 81: 223-232, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27612992

RESUMEN

The objective of this study was to compare premature ovarian failure animal models established by several different source of inducers. Female ICR mice, KM mice, and SD rats were treated by cyclophosphamide at 120 mg/kg, busulfan at 12 mg/kg, cisplatin at 3 or 4 mg/kg, 4-vinylcyclohexene diepoxide at 160 mg/kg, 35% galactose food pellet, and tripterygium glycosides at 50 mg/kg, respectively. Parameters were analyzed by body weight, serum concentration level of related hormones, ovarian and uterine pathological examination. The results indicated the body weight of mice increased very slowly following single dose of cyclophosphamide (p < 0.05) with damaged ovary; repeated doses of cisplatin could induce body weight significantly decreased (p < 0.01) with a rising trend of serum LH concentration, declining tendency of serum E2 concentration and injured ovary and uterus; 4-vinylcyclohexene diepoxide also hindered the mice growing (p < 0.05) with damaged ovary and uterus; the body weight of mice feed by 35% galactose food pellet increased slowly (p < 0.05) with dramatically higher serum concentration level of galactose, albumin, and total protein (p < 0.001) and injured ovary. Busulfan and tripterygium glycosides did not present obvious evidences. In conclusion, the inducers presented their respective features in such animal models and should be appropriately applied in preventive methods.


Asunto(s)
Modelos Animales de Enfermedad , Ovario/efectos de los fármacos , Ovario/patología , Insuficiencia Ovárica Primaria/inducido químicamente , Animales , Busulfano/administración & dosificación , Busulfano/farmacología , Cisplatino/administración & dosificación , Cisplatino/farmacología , Ciclohexenos/administración & dosificación , Ciclohexenos/farmacología , Ciclofosfamida/administración & dosificación , Ciclofosfamida/farmacología , Relación Dosis-Respuesta a Droga , Femenino , Galactosa/administración & dosificación , Galactosa/farmacología , Glicósidos/administración & dosificación , Glicósidos/farmacología , Ratones , Ratones Endogámicos , Insuficiencia Ovárica Primaria/patología , Insuficiencia Ovárica Primaria/fisiopatología , Ratas , Ratas Sprague-Dawley , Tripterygium/química , Compuestos de Vinilo/administración & dosificación , Compuestos de Vinilo/farmacología
14.
J Vis Exp ; (105): e53038, 2015 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-26556528

RESUMEN

In this article a method for the fabrication and reproducible in-vitro evaluation of conducting polymer nanoparticles blended with fullerene as the next generation photosensitizers for Photodynamic Therapy (PDT) is reported. The nanoparticles are formed by hydrophobic interaction of the semiconducting polymer MEH-PPV (poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene]) with the fullerene PCBM (phenyl-C61-butyric acid methyl ester) in the presence of a non-compatible solvent. MEH-PPV has a high extinction coefficient that leads to high rates of triplet formation, and efficient charge and energy transfer to the fullerene PCBM. The latter processes enhance the efficiency of the PDT system through fullerene assisted triplet and radical formation, and ultrafast deactivation of MEH-PPV excited stated. The results reported here show that this nanoparticle PDT sensitizing system is highly effective and shows unexpected specificity to cancer cell lines.


Asunto(s)
Fulerenos/química , Nanopartículas/química , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/química , Polímeros/química , Compuestos de Vinilo/química , Animales , Línea Celular , Línea Celular Tumoral , Células Epiteliales/efectos de los fármacos , Femenino , Fulerenos/administración & dosificación , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Ratones , Nanopartículas/administración & dosificación , Neoplasias Ováricas/tratamiento farmacológico , Fármacos Fotosensibilizantes/administración & dosificación , Polímeros/administración & dosificación , Compuestos de Vinilo/administración & dosificación
15.
Am J Physiol Regul Integr Comp Physiol ; 309(12): R1546-52, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26491098

RESUMEN

Premenopausal females are resistant to the development of hypertension, and this protection is lost after the onset of menopause, resulting in a sharp increase in disease onset and severity. However, it is unknown how a fluctuating ovarian hormone environment during the transition from perimenopause to menopause impacts the onset of hypertension, and whether interventions during perimenopause prevent disease onset after menopause. A gradual transition to menopause was induced by repeated daily injections of 4-vinylcyclohexene diepoxide (VCD). ANG II (800 ng·kg(-1)·min(-1)) was infused into perimenopausal and menopausal female mice for 14 days. A separate cohort of mice received 17ß-estradiol replacement during perimenopause. ANG II infusion produced significantly higher mean arterial pressure (MAP) in menopausal vs. cycling females, and 17ß-estradiol replacement prevented this increase. In contrast, MAP was not significantly different when ANG II was infused into perimenopausal and cycling females, suggesting that female resistance to ANG II-induced hypertension is intact during perimenopause. ANG II infusion caused a significant glomerular hypertrophy, and hypertrophy was not impacted by hormonal status. Expression levels of aquaporin-2 (AQP2), a collecting duct protein, have been suggested to reflect blood pressure. AQP2 protein expression was significantly downregulated in the renal cortex of the ANG II-infused menopause group, where blood pressure was increased. AQP2 expression levels were restored to control levels with 17ß-estradiol replacement. This study indicates that the changing hormonal environment in the VCD model of menopause impacts the severity of ANG II-induced hypertension. These data highlight the utility of the ovary-intact VCD model of menopause as a clinically relevant model to investigate the physiological mechanisms of hypertension that occur in women during the transition into menopause.


Asunto(s)
Angiotensina II , Presión Arterial/efectos de los fármacos , Ciclohexenos/administración & dosificación , Estradiol/administración & dosificación , Terapia de Reemplazo de Estrógeno , Hipertensión/inducido químicamente , Hipertensión/prevención & control , Menopausia/efectos de los fármacos , Compuestos de Vinilo/administración & dosificación , Animales , Acuaporina 2/metabolismo , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Esquema de Medicación , Femenino , Hipertensión/metabolismo , Hipertensión/patología , Hipertensión/fisiopatología , Inyecciones Intraperitoneales , Corteza Renal/efectos de los fármacos , Corteza Renal/metabolismo , Corteza Renal/patología , Menopausia/metabolismo , Ratones Endogámicos C57BL , Perimenopausia , Factores de Riesgo , Factores de Tiempo
16.
Mem Inst Oswaldo Cruz ; 110(2): 166-73, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25946239

RESUMEN

Despite recent advances in the treatment of some forms of leishmaniasis, the available drugs are still far from ideal due to inefficacy, parasite resistance, toxicity and cost. The wide-spectrum antimicrobial activity of 2-nitrovinylfuran compounds has been described, as has their activity against Trichomonas vaginalis and other protozoa. Thus, the aim of this study was to test the antileishmanial activities of six 2-nitrovinylfurans in vitro and in a murine model of leishmaniasis. Minimum parasiticide concentration (MPC) and 50% inhibitory concentration (IC50) values for these compounds against the promastigotes of Leishmania amazonensis, Leishmania infantum and Leishmania braziliensis were determined, as were the efficacies of two selected compounds in an experimental model of cutaneous leishmaniasis (CL) caused by L. amazonensis in BALB/c mice. All of the compounds were active against the promastigotes of the three Leishmania species tested. IC50 and MPC values were in the ranges of 0.8-4.7 µM and 1.7-32 µM, respectively. The compounds 2-bromo-5-(2-bromo-2-nitrovinyl)-furan (furvina) and 2-bromo-5-(2-methyl-2-nitrovinyl)-furan (UC245) also reduced lesion growth in vivo at a magnitude comparable to or higher than that achieved by amphotericin B treatment. The results demonstrate the potential of this class of compounds as antileishmanial agents and support the clinical testing of Dermofural(r) (a furvina-containing antifungal ointment) for the treatment of CL.


Asunto(s)
Antiprotozoarios/administración & dosificación , Proliferación Celular/efectos de los fármacos , Furanos/administración & dosificación , Leishmania/efectos de los fármacos , Leishmaniasis Cutánea/tratamiento farmacológico , Anfotericina B/administración & dosificación , Animales , Ensayos Clínicos como Asunto , Modelos Animales de Enfermedad , Femenino , Humanos , Técnicas In Vitro , Concentración 50 Inhibidora , Células KB/efectos de los fármacos , Leishmania/clasificación , Leishmania/crecimiento & desarrollo , Ratones Endogámicos BALB C , Enfermedades Desatendidas/tratamiento farmacológico , Factores de Tiempo , Compuestos de Vinilo/administración & dosificación
17.
Bull Exp Biol Med ; 158(1): 46-8, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25403395

RESUMEN

We studied the effects of subcutaneous and intragastrical administration of synthesized compound thiazoline ammonium 4-chlorophenyl-2-hydroxy-4-oxo-2-butenoate (FS 169) on blood clotting in vitro and in vivo in rabbits. Compound FS 169 significantly prolongs clotting time in vitro; its activity is comparable with that of heparin. When administered subcutaneously, the substance is rapidly absorbed and significantly reduces blood clotting by 102.9% from the initial clotting time within 30 min. After intragastric administration of the substance, maximum activity (133.0% of the baseline clotting time) was observed in 30 min after administration. The drug effect upon subcutaneous and intragastrical administration lasted for 2 h.


Asunto(s)
Acetatos/administración & dosificación , Anticoagulantes/administración & dosificación , Derivados del Benceno/administración & dosificación , Compuestos de Vinilo/administración & dosificación , Acetatos/farmacocinética , Animales , Animales no Consanguíneos , Anticoagulantes/farmacocinética , Derivados del Benceno/farmacocinética , Coagulación Sanguínea , Evaluación Preclínica de Medicamentos , Heparina/administración & dosificación , Inyecciones Subcutáneas , Conejos , Compuestos de Vinilo/farmacocinética , Tiempo de Coagulación de la Sangre Total
18.
J Anim Sci ; 92(9): 3895-905, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25057028

RESUMEN

Nutrient digestibility and the effect of high dietary inclusion of canola meals from Brassica napus black (BNB) and Brassica juncea yellow (BJY) on growing and weaned pigs performance were determined. In Exp.1, 6 ileal cannulated barrows (initial BW = 20.7 ± 1.5 kg) were used to determine the apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of AA in BNB and BJY. Pigs were allotted to diets containing either BNB or BJY as the sole source of protein in a crossover design to give 6 replicates per diet. The SID of all AA in BNB and BJY were similar. In Exp. 2, 168 weaned pigs (initial BW = 7.61 ± 0.76 kg) were assigned in a randomized complete block design to 7 diets (n = 24) consisting of a wheat-soybean meal-based control diet and 6 diets containing 5, 10 or 15% of canola meal derived from either BNB or BJY to determine the effect of different dietary inclusion on growth performance over a 28-d period postweaning. Diets were formulated to contain similar NE and SID of Lys. There were no differences in growth performance among treatments. In Exp. 3, 162 weaned pigs (initial BW = 7.26 ± 0.70 kg) were used to determine the effect of high BNB and BJY inclusion level without or with multicarbohydrase supplementation on growth performance and apparent total tract digestibility (ATTD) of CP, DM, and GE. A wheat-soybean meal-based control diet and 8 diets containing 20 and 25% of either BNB or BJY without or with added multi-carbohydrase were formulated (n = 18) to contain comparable NE and similar SID of Lys contents. Feeding the diets containing 25% of BNB or BJY supported similar growth performance as those containing 20%. The multi-carbohydrase had no effect on growth performance but improved (P < 0.05) the ATTD of DM, CP, and GE compared with those fed nonsupplemented diets irrespective of canola meal type. Diets containing 25% canola meal had lower (P < 0.05) ATTD of DM, CP, and GE regardless of canola meal type compared with the 20% canola meal diets. There was an interaction (P < 0.05) between canola meal type and inclusion level on ATTD of DM in which ATTD of DM decreased with increasing inclusion of both canola meal types. Results of the current study indicate that both BNB and BJY can be included up to 25% in weaned pig diets without compromising performance as long as the diets are formulated on an NE and SID of Lys basis. Also, enzyme addition improved the ATTD of CP, DM, and GE in weaned pigs in both BNB and BJY diets.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Brassica napus , Digestión/efectos de los fármacos , Fenómenos Fisiológicos del Sistema Digestivo , Planta de la Mostaza , Fenoles/farmacología , Porcinos/crecimiento & desarrollo , Compuestos de Vinilo/farmacología , Aminoácidos , Alimentación Animal/análisis , Animales , Estudios Cruzados , Dieta/veterinaria , Suplementos Dietéticos , Digestión/fisiología , Crecimiento y Desarrollo/efectos de los fármacos , Crecimiento y Desarrollo/fisiología , Masculino , Fenoles/administración & dosificación , Fenoles/análisis , Porcinos/fisiología , Compuestos de Vinilo/administración & dosificación , Compuestos de Vinilo/análisis
19.
J Vis Exp ; (86)2014 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-24747886

RESUMEN

The risk of cardiovascular disease (CVD) increases in post-menopausal women, yet, the role of exercise, as a preventative measure for CVD risk in post-menopausal women has not been adequately studied. Accordingly, we investigated the impact of voluntary cage-wheel exercise and forced treadmill exercise on cardiac adaptation in menopausal mice. The most commonly used inducible model for mimicking menopause in women is the ovariectomized (OVX) rodent. However, the OVX model has a few dissimilarities from menopause in humans. In this study, we administered 4-vinylcyclohexene diepoxide (VCD) to female mice, which accelerates ovarian failure as an alternative menopause model to study the impact of exercise in menopausal mice. VCD selectively accelerates the loss of primary and primordial follicles resulting in an endocrine state that closely mimics the natural progression from pre- to peri- to post-menopause in humans. To determine the impact of exercise on exercise capacity and cardiac adaptation in VCD-treated female mice, two methods were used. First, we exposed a group of VCD-treated and untreated mice to a voluntary cage wheel. Second, we used forced treadmill exercise to determine exercise capacity in a separate group VCD-treated and untreated mice measured as a tolerance to exercise intensity and endurance.


Asunto(s)
Adaptación Fisiológica/fisiología , Ciclohexenos/administración & dosificación , Corazón/fisiología , Menopausia/fisiología , Modelos Animales , Ovario/efectos de los fármacos , Condicionamiento Físico Animal , Compuestos de Vinilo/administración & dosificación , Animales , Femenino , Menopausia/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Ovario/fisiología
20.
J Zoo Wildl Med ; 44(4 Suppl): S9-17, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24437079

RESUMEN

Rodent pests cause major damage to the world's agricultural crops and food stores. Rodenticides used since World War II did not lead to sustained reduction of rodent populations, and so fertility control is becoming attractive because rats reproduce with great efficiency. Chemical acceleration of ovarian failure via oral dosing also would improve management of rat pest populations. The chemical 4-vinylcyclohexene diepoxide (VCD) is orally efficacious, causing depletion of nonregenerating primordial ovarian follicles of Sprague-Dawley rats. However, to cause rapid reduction in pups in the first breeding cycle after dosing, all stages of ovarian follicle development must be targeted. To achieve this goal, the Chinese herb triptolide was tested because it can precipitate apoptosis and deplete growing follicles. The impact of triptolide was tested in cultured postnatal day 4 Sprague-Dawley rat pup ovaries. Triptolide at 5 nM caused 100% primordial, primary, and secondary follicle depletion after 8 days of culture, compared to 38% follicle depletion caused by VCD at 30 microM. Next, a palatable rat bait was developed, containing 1% VCD with increasing concentrations of triptolide at 25, 50, and 100 microg/kg body weight. Rats ate an average 3-6% of their body weight/day over 15 feeding days. Two days after the end of baiting, rats were euthanized to conduct necropsies and collect ovaries to count all follicular stages and corpora lutea. At 50 microg triptolide/kg body weight, there was significant reduction of all follicular stages; primordial follicles were 50% lower, secondary follicles were 64% lower, antral follicles were 80% lower, and there were no corpora lutea. These results suggest that combining VCD and triptolide in an oral bait leads to significantly compromised rat ovarian function and reduced ovulations, and is likely to reduce pup production.


Asunto(s)
Anticonceptivos Femeninos/farmacología , Ciclohexenos/farmacología , Diterpenos/farmacología , Folículo Ovárico/efectos de los fármacos , Fenantrenos/farmacología , Compuestos de Vinilo/farmacología , Animales , Anticonceptivos Femeninos/administración & dosificación , Ciclohexenos/administración & dosificación , Diterpenos/administración & dosificación , Compuestos Epoxi/administración & dosificación , Compuestos Epoxi/farmacología , Femenino , Fenantrenos/administración & dosificación , Regulación de la Población , Ratas , Ratas Sprague-Dawley , Compuestos de Vinilo/administración & dosificación
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