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1.
Artículo en Inglés | MEDLINE | ID: mdl-38776990

RESUMEN

OBJECTIVE: Previous research emphasises correcting deformities resulting from spine fractures by restoring sagittal alignment and vertebral height. This study aims to compare radiological outcomes, including sagittal index (SI) and loss of vertebral body height (LVBH), between stand-alone posterior stabilisation (Group I) and the posteroanterior/combined approach (Group II) in the operative management of traumatic thoracic or lumbar spine fractures. METHODS: In this retrospective single-centre study, all patients with traumatic spine fractures (T1 to L5) undergoing surgical stabilisation between January 1, 2015, and May 31, 2021, were included. Two spine surgeons independently assessed imaging, recording SI and LVBH values at baseline, after each surgical intervention, and during follow-up (at least three months post-treatment). The mean values of SI and LVBH between the assessing surgeons were utilised. Linear mixed-effects regression models, adjusted to baseline values, compared SI and LVBH between the two groups. RESULTS: 71 patients (42 men), median age 38 years (IQR 28 to 54), with a median follow-up of 4 months (IQR 3 to 17), were included. 32 were in Group I and 39 in Group II. 40 fractures included the thoracolumbar junction (T12 or L1), 15 affected the thoracic- and 14 the lumbar spine. The regression model revealed superior sagittal alignment in Group II, with an adjusted mean difference for SI of -4.24 (95% CI -7.13 to -1.36; p-value=0.004), and enhanced restoration of vertebral body height with an adjusted mean difference for LVBH of 0.11 in the combined approach (95% CI 0.02 to 0.20; p-value=0.02). Nine postoperative complications occurred in the entire cohort (4 in Group I and 5 in Group II). CONCLUSIONS: Combined posteroanterior stabilisation for spine fractures improves deformities by enhancing sagittal alignment and increasing vertebral body height, with acceptable morbidity compared to the stand-alone posterior approach.

2.
Molecules ; 29(2)2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38257347

RESUMEN

Breast cancer (BC) is one of the most common cancers in women and is a major cause of female cancer-related deaths. BC is a multifactorial disease caused by the dysregulation of many genes, raising the need to find novel drugs that function by targeting several signaling pathways. The antitumoral drug thymoquinone (TQ), found in black seed oil, has multitargeting properties against several signaling pathways. This study evaluated the inhibitory effects of TQ on the MCF7 and T47D human breast cancer cell lines and its antitumor activity against BC induced by a single oral dose (65 mg/kg) of 7,12-dimethylbenzanthracene (DMBA) in female rats. The therapeutic activity was evaluated in DMBA-treated rats who received oral TQ (50 mg/kg) three times weekly. TQ-treated MCF7 and T47D cells showed concentration-dependent inhibition of cell proliferation and induction of apoptosis. TQ also decreased the expression of DNA methyltransferase 1 (DNMT1) in both cancer cell types. In DMBA-treated animals, TQ inhibited the number of liver and kidney metastases. These effects were associated with a reduction in DNMT1 mRNA expression. These results indicate that TQ has protective effects against breast carcinogens through epigenetic mechanisms involving DNMT1 inhibition.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , Animales , Ratas , Neoplasias de la Mama/inducido químicamente , Neoplasias de la Mama/tratamiento farmacológico , Benzoquinonas/farmacología , 9,10-Dimetil-1,2-benzantraceno/toxicidad , Apoptosis
3.
Molecules ; 27(9)2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35566130

RESUMEN

Nigella sativa oil, commonly known as black seed oil (BSO), is a well-known Mediterranean food, and its consumption is associated with beneficial effects on human health. A large number of BSO's therapeutic properties is attributed to its pharmacologically active compound, thymoquinone (TQ), which inhibits cell proliferation and induces apoptosis by targeting several epigenetic players, including the ubiquitin-like, containing plant homeodomain (PHD) and an interesting new gene, RING finger domains 1 (UHRF1), and its partners, DNA methyltransferase 1 (DNMT1) and histone deacetylase 1 (HDAC1). This study was designed to compare the effects of locally sourced BSO with those of pure TQ on the expression of the epigenetic complex UHRF1/DNMT1/HDAC1 and the related events in several cancer cells. The gas chromatographs obtained from GC-MS analyses of extracted BSO showed that TQ was the major volatile compound. BSO significantly inhibited the proliferation of MCF-7, HeLa and Jurkat cells in a dose-dependent manner, and it induced apoptosis in these cell lines. BSO-induced inhibitory effects were associated with a significant decrease in mRNA expression of UHRF1, DNMT1 and HDAC1. Molecular docking and MD simulation showed that TQ had good binding affinity to UHRF1 and HDAC1. Of note, TQ formed a stable metal coordinate bond with zinc tom, found in the active site of the HDAC1 protein. These findings suggest that the use of TQ-rich BSO represents a promising strategy for epigenetic therapy for both solid and blood tumors through direct targeting of the trimeric epigenetic complex UHRF1/DNMT1/ HDAC1.


Asunto(s)
Neoplasias , Nigella sativa , Benzoquinonas/farmacología , Proteínas Potenciadoras de Unión a CCAAT/genética , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Epigénesis Genética , Humanos , Simulación del Acoplamiento Molecular , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Nigella sativa/metabolismo , Aceites de Plantas/farmacología , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
4.
Molecules ; 27(2)2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-35056791

RESUMEN

Aldehyde dehydrogenase-1a1 (ALDH1a1), the enzyme responsible for the oxidation of retinal into retinoic acid, represents a key therapeutic target for the treatment of debilitating disorders such as cancer, obesity, and inflammation. Drugs that can inhibit ALDH1a1 include disulfiram, an FDA-approved drug to treat chronic alcoholism. Disulfiram, by carbamylation of the catalytic cysteines, irreversibly inhibits ALDH1a1 and ALDH2. The latter is the isozyme responsible for important physiological processes such as the second stage of alcohol metabolism. Given the fact that ALDH1a1 has a larger substrate tunnel than that in ALDH2, replacing disulfiram ethyl groups with larger motifs will yield selective ALDH1a1 inhibitors. We report herein the synthesis of new inhibitors of ALDH1a1 where (hetero)aromatic rings were introduced into the structure of disulfiram. Most of the developed compounds retained the anti-ALDH1a1 activity of disulfiram; however, they were completely devoid of inhibitory activity against ALDH2.


Asunto(s)
Inhibidores del Acetaldehído Deshidrogenasa/química , Inhibidores del Acetaldehído Deshidrogenasa/farmacología , Familia de Aldehído Deshidrogenasa 1/antagonistas & inhibidores , Disulfiram/química , Disulfiram/farmacología , Retinal-Deshidrogenasa/antagonistas & inhibidores , Inhibidores del Acetaldehído Deshidrogenasa/síntesis química , Inhibidores del Acetaldehído Deshidrogenasa/metabolismo , Familia de Aldehído Deshidrogenasa 1/química , Familia de Aldehído Deshidrogenasa 1/metabolismo , Aldehído Deshidrogenasa Mitocondrial/antagonistas & inhibidores , Aldehído Deshidrogenasa Mitocondrial/química , Aldehído Deshidrogenasa Mitocondrial/metabolismo , Disulfiram/análogos & derivados , Disulfiram/síntesis química , Humanos , Simulación del Acoplamiento Molecular , Proteínas Recombinantes/metabolismo , Retinal-Deshidrogenasa/química , Retinal-Deshidrogenasa/metabolismo
5.
Pharmaceutics ; 13(7)2021 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-34371723

RESUMEN

Nano-emulsions consist of stable suspensions of nano-scaled droplets that have huge loading capacities and are formulated with safe compounds. For these reasons, a large number of studies have described the potential uses of nano-emulsions, focusing on various aspects such as formulation processes, loading capabilities, and surface modifications. These studies typically concern direct nano-emulsions (i.e., oil-in-water), whereas studies on reverse nano-emulsions (i.e., water-in-oil) remain anecdotal. However, reverse nano-emulsion technology is very promising (e.g., as an alternative to liposome technology) for the development of drug delivery systems that encapsulate hydrophilic compounds within double droplets. The spontaneous emulsification process has the added advantages of optimization of the energetic yield, potential for industrial scale-up, improved loading capabilities, and preservation of fragile compounds targeted for encapsulation. In this study, we propose a detailed investigation of the processes and formulation parameters involved in the spontaneous nano-emulsification that produces water-in-oil nano-emulsions. The following details were addressed: (i) the order of mixing of the different compounds (method A and method B), (ii) mixing rates, (iii) amount of surfactants, (iv) type and mixture of surfactants, (v) amount of dispersed phase, and (vi) influence of the nature of the oil. The results emphasized the effects of the formulation parameters (e.g., the volume fraction of the dispersed phase, nature or concentration of surfactant, or nature of the oil) on the nature and properties of the nano-emulsions formed.

6.
Molecules ; 26(11)2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34206005

RESUMEN

Phenanthroindolizidines, such as antofine and tylophorine, are a family of natural alkaloids isolated from different species of Asclepiadaceas. They are characterized by interesting biological activities, such as pronounced cytotoxicity against different human cancerous cell lines, including multidrug-resistant examples. Nonetheless, these derivatives are associated with severe neurotoxicity and loss of in vivo activity due to the highly lipophilic nature of the alkaloids. Here, we describe the development of highly polar prodrugs of antofine and tylophorine as hypoxia-targeted prodrugs. The developed quaternary ammonium salts of phenanthroindolizidines showed high chemical and metabolic stability and are predicted to have no penetration through the blood-brain barrier. The designed prodrugs displayed decreased cytotoxicity when tested under normoxic conditions. However, their cytotoxic activity considerably increased when tested under hypoxic conditions.


Asunto(s)
Alcaloides/química , Antineoplásicos/síntesis química , Indoles/química , Indolizinas/química , Fenantrenos/química , Fenantrolinas/química , Profármacos/síntesis química , Compuestos de Amonio Cuaternario/síntesis química , Compuestos de Amonio Cuaternario/farmacología , Hipoxia Tumoral/efectos de los fármacos , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Células CHO , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cricetulus , Ensayos de Selección de Medicamentos Antitumorales , Células HEK293 , Humanos , Células MCF-7 , Estructura Molecular , Profármacos/química , Profármacos/farmacología , Compuestos de Amonio Cuaternario/química , Relación Estructura-Actividad
7.
Molecules ; 26(11)2021 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-34070869

RESUMEN

Monoacylglycerol lipase (MAGL) is a key enzyme in the human endocannabinoid system. It is also the main enzyme responsible for the conversion of 2-arachidonoyl glycerol (2-AG) to arachidonic acid (AA), a precursor of prostaglandin synthesis. The inhibition of MAGL activity would be beneficial for the treatment of a wide range of diseases, such as inflammation, neurodegeneration, metabolic disorders and cancer. Here, the author reports the pharmacological evaluation of new disulfiram derivatives as potent inhibitors of MAGL. These analogues displayed high inhibition selectivity over fatty acid amide hydrolase (FAAH), another endocannabinoid-hydrolyzing enzyme. In particular, compound 2i inhibited MAGL in the low micromolar range. However, it did not show any inhibitory activity against FAAH.


Asunto(s)
Disulfiram/farmacología , Monoacilglicerol Lipasas/antagonistas & inhibidores , Monoacilglicerol Lipasas/química , Amidohidrolasas/química , Ácidos Araquidónicos/química , Carbamatos/farmacología , Disulfiram/análogos & derivados , Endocannabinoides/química , Endocannabinoides/metabolismo , Inhibidores Enzimáticos/farmacología , Glicéridos/química , Humanos , Hidrólisis , Monoglicéridos/química , Relación Estructura-Actividad
8.
Cancers (Basel) ; 13(8)2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33921128

RESUMEN

The tumor suppressor p73 is a member of the p53 family and is expressed as different isoforms with opposing properties. The TAp73 isoforms act as tumor suppressors and have pro-apoptotic effects, whereas the ΔNp73 isoforms lack the N-terminus transactivation domain and behave as oncogenes. The TAp73 protein has a high degree of similarity with both p53 function and structure, and it induces the regulation of various genes involved in the cell cycle and apoptosis. Unlike those of the p53 gene, the mutations in the p73 gene are very rare in tumors. Cancer cells have developed several mechanisms to inhibit the activity and/or expression of p73, from the hypermethylation of its promoter to the modulation of the ratio between its pro- and anti-apoptotic isoforms. The p73 protein is also decorated by a panel of post-translational modifications, including phosphorylation, acetylation, ubiquitin proteasomal pathway modifications, and small ubiquitin-related modifier (SUMO)ylation, that regulate its transcriptional activity, subcellular localization, and stability. These modifications orchestrate the multiple anti-proliferative and pro-apoptotic functions of TAp73, thereby offering multiple promising candidates for targeted anti-cancer therapies. In this review, we summarize the current knowledge of the different pathways implicated in the regulation of TAp73 at the post-translational level. This review also highlights the growing importance of targeting the post-translational modifications of TAp73 as a promising antitumor strategy, regardless of p53 status.

9.
Genes (Basel) ; 12(5)2021 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-33922029

RESUMEN

Silencing of tumor suppressor genes (TSGs) through epigenetic mechanisms, mainly via abnormal promoter DNA methylation, is considered a main mechanism of tumorigenesis. The abnormal DNA methylation profiles are transmitted from the cancer mother cell to the daughter cells through the involvement of a macromolecular complex in which the ubiquitin-like containing plant homeodomain (PHD), and an interesting new gene (RING) finger domains 1 (UHRF1), play the role of conductor. Indeed, UHRF1 interacts with epigenetic writers, such as DNA methyltransferase 1 (DNMT1), histone methyltransferase G9a, erasers like histone deacetylase 1 (HDAC1), and functions as a hub protein. Thus, targeting UHRF1 and/or its partners is a promising strategy for epigenetic cancer therapy. The natural compound thymoquinone (TQ) exhibits anticancer activities by targeting several cellular signaling pathways, including those involving UHRF1. In this review, we highlight TQ as a potential multitarget single epidrug that functions by targeting the UHRF1/DNMT1/HDAC1/G9a complex. We also speculate on the possibility that TQ might specifically target UHRF1, with subsequent regulatory effects on other partners.


Asunto(s)
Benzoquinonas/farmacología , Proteínas Potenciadoras de Unión a CCAAT/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Ubiquitina-Proteína Ligasas/antagonistas & inhibidores , Carcinogénesis/efectos de los fármacos , Carcinogénesis/metabolismo , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Metilación de ADN/efectos de los fármacos , Epigénesis Genética/efectos de los fármacos , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Regiones Promotoras Genéticas/efectos de los fármacos
10.
Bioorg Med Chem Lett ; 40: 127958, 2021 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-33744437

RESUMEN

Disulfiram is an FDA-approved drug used to treat chronic alcoholism. This drug works by blocking the second step of ethanol metabolism by inhibiting aldehyde dehydrogenase-2 (ALDH2), the enzyme responsible for acetaldehyde oxidation into acetic acid. This leads to the accumulation of acetaldehyde in the blood following alcohol ingestion and to highly unpleasant symptoms known as acetaldehyde syndrome. Disulfiram also inhibits ALDH1a1, another member of the aldehyde dehydrogenases that catalyzes the oxidation of retinal into retinoic acid. ALDH1a1 represents a key therapeutic target for the treatment of important diseases such as cancer and obesity. The substrate tunnel is larger in ALDH1a1 than in ALDH2; therefore. Thus, replacing disulfiram ethyl groups with larger groups will yield selective ALDH1a1 inhibitors. In this work, we successfully synthesized derivative 2b, in which two ethyl groups were replaced by two para fluorobenzyl groups. The 2b derivative showed a comparable activity to disulfiram against ALDH1a1; however, it was completely devoid of inhibitory activity against ALDH2.


Asunto(s)
Inhibidores del Acetaldehído Deshidrogenasa/química , Disuasivos de Alcohol/química , Familia de Aldehído Deshidrogenasa 1/antagonistas & inhibidores , Disulfiram/análogos & derivados , Retinal-Deshidrogenasa/antagonistas & inhibidores , Inhibidores del Acetaldehído Deshidrogenasa/síntesis química , Disuasivos de Alcohol/síntesis química , Familia de Aldehído Deshidrogenasa 1/química , Aldehído Deshidrogenasa Mitocondrial/antagonistas & inhibidores , Aldehído Deshidrogenasa Mitocondrial/química , Disulfiram/síntesis química , Pruebas de Enzimas , Humanos , Retinal-Deshidrogenasa/química , Especificidad por Sustrato
11.
Molecules ; 26(4)2021 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-33572107

RESUMEN

In developing countries, crop deterioration is mainly caused by inappropriate storage conditions that promote insect infestation. Synthetic pesticides are associated with serious adverse effects on humans and the environment. Thus, finding alternative "green" insecticides is a very pressing need. Calotropis procera (Aiton) Dryand (Apocynaceae) growing in Saudi Arabia was selected for this purpose. LC-MS/MS analysis was applied to investigate the metabolic composition of different C. procera extracts. Particularly, C. procera latex and leaves showed a high presence of cardenolides including calactin, uscharidin, 15ß-hydroxy-calactin, 16ß-hydroxy-calactin, and 12ß-hydroxy-calactin. The ovicidal activity of the extracts from different plant organs (flowers, leaves, branches, roots), and of the latex, against Cadra cautella (Walker) (Lepidoptera, Pyralidae) was assessed. Extracts of C. procera roots displayed the most potent activity with 50% of C. cautella eggs not hatching at 10.000 ppm (1%).


Asunto(s)
Calotropis/química , Óvulo/efectos de los fármacos , Óvulo/fisiología , Fitoquímicos/farmacología , Extractos Vegetales/farmacología , Animales , Flores/química , Látex/química , Mariposas Nocturnas , Hojas de la Planta/química , Raíces de Plantas/química
12.
Langmuir ; 37(8): 2586-2595, 2021 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-33577340

RESUMEN

In this work, we used an original experimental setup to examine the behavior of insoluble monolayers made with pH-sensitive lipids. Two kinds of unsaturated lipids were chosen: a cationic one (lipid 1) bearing an ammonium headgroup and an anionic one (lipid 2) terminated with an acidic phenol group. The lipids were deposited onto an air bubble interface maintained in an aqueous phase and, after stabilization, were subjected to a series of compressions performed at different pH values. These experiments disclosed a gradual increase in the specific area per molecule when lipids were neutralized. Imposing a pH variation at constant bubble volume also provided surface pressure profiles that confirmed this molecular behavior. As complementary characterization, dilatational rheology disclosed a phase transition from a purely elastic monophasic system to a viscoelastic two-phase system. We hypothesized that this unexpected increase in the specific area with lipid neutralization is related to the presence of unsaturations in each of the two branches of the hydrophobic tails that induce disorder, thereby increasing the molecular area at the interface. Application of the two-dimensional Volmer equation of state allowed the generation of quantitative values for the specific areas that showed variations with pH. It also allowed the determination of apparent pKa values, which are affected by both the electrostatic potential within the monolayer and the affinity of the lipid polar head for the aqueous phase.

13.
J Mol Biol ; 433(6): 166659, 2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33010306

RESUMEN

Epigenetic modifications and nucleosome positioning play an important role in modulating gene expression. However, how the patterns of epigenetic modifications and nucleosome positioning are established around promoters is not well understood. Here, we have addressed these questions in a series of genome-wide experiments coupled to a novel bioinformatic analysis approach. Our data reveal a clear correlation between CpG density, promoter activity and accumulation of active or repressive histone marks. CGI boundaries define the chromatin promoter regions that will be epigenetically modified. CpG-rich promoters are targeted by histone modifications and histone variants, while CpG-poor promoters are regulated by DNA methylation. CGIs boundaries, but not transcriptional activity, are essential determinants of H2A.Z positioning in vicinity of the promoters, suggesting that the presence of H2A.Z is not related to transcriptional control. Accordingly, H2A.Z depletion has no impact on gene expression of arrested mouse embryonic fibroblasts. Therefore, the underlying DNA sequence, the promoter CpG density and, to a lesser extent, transcriptional activity, are key factors implicated in promoter chromatin architecture.


Asunto(s)
Islas de CpG , Epigénesis Genética , Epigenoma , Histonas/genética , Regiones Promotoras Genéticas , Procesamiento Proteico-Postraduccional , Animales , Cromatina/metabolismo , Cromatina/ultraestructura , Ensamble y Desensamble de Cromatina , Biología Computacional/métodos , Metilación de ADN , Embrión de Mamíferos , Fibroblastos/citología , Fibroblastos/metabolismo , Histonas/química , Histonas/deficiencia , Histonas/metabolismo , Ratones , Ratones Noqueados , Cultivo Primario de Células , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
14.
Artículo en Inglés | MEDLINE | ID: mdl-32831876

RESUMEN

The prevalence of nosocomial infections due to multidrug resistant (MDR) bacterial strains is associated with high morbidity and mortality. Folk medicine and ethnopharmacological data can provide a broad range of plants with promising antimicrobial activity. Triphala, an Ayurvedic formula composed of three different plants: Terminalia chebula Retz., Terminalia bellirica (Gaertn.) Roxb. (Combretaceae), and Phyllanthus emblica L. (Phyllanthaceae), is used widely for various microbial infections. Various extraction techniques were applied in the extraction of the biologically active constituents of Triphala in order to compare their efficiency. Microwave-assisted extraction (MAE) was shown to be the most efficient method based on yield, extraction time, and selectivity. The Triphala hydroalcoholic extract (TAE) has been chemically characterized with spectroscopic and chromatographic techniques. Triphala hydroalcoholic extract was evaluated alone or with carvacrol. Different drug formulations including cream and nanoemulsion hydrogel were prepared to assess the antimicrobial activity against selected microorganism strains including Gram-positive and Gram-negative bacteria and fungi. We used a lipophilic oil of carvacrol (5 mg/mL) and a hydrophilic TAE (5 mg/mL) ingredient in a dosage form. Two solutions were created: hydrogel containing nanoemulsion as a lipophilic vector dispersed in the gel as a hydrophilic vehicle and a cream formulation, an oil-in-water emulsion. In both cases, the concentration was 250 mg of active ingredient in 50 mL of final formulation. The formulas developed were stable from a physical and chemical perspective. In the nanoemulsion hydrogel, the oil droplet size ranged from 124 to 129 nm, with low polydispersity index (PdI) 0.132 ± 0.013 and negative zeta potential -46.4 ± 4.3 mV. For the cream, the consistency factor (cetyl alcohol and white wax) induced immobilization of the matrix structure and the stability. Triphala hydroalcoholic extract in drug nanoformulation illustrated might be an adjuvant antimicrobial agent for treating various microbial infections.

15.
J Colloid Interface Sci ; 578: 768-778, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32574910

RESUMEN

Nano-emulsion consists of a dispersion of oil droplets sizing below 200 nm, in aqueous continuous phase, and generally stabilized by low-molecular-weight surfactants. These stable nano-carriers are able to encapsulate and transport lipophilic molecules poorly soluble in water. However, the question on the leakage and release mechanisms of an active pharmaceutical ingredient, from oil nano-droplets to an acceptor medium has not been clearly addressed. Herein, we developed a simple fluorescence approach based on self-quenching of lipophilic fluorophore-based on Nile Red (NR668) to monitor cargo transfer from lipid nano-droplets to the acceptor medium. In this method, the fluorophore release can be monitored by the increase in its fluorescence quantum yield and the blue shift in its emission spectrum. The studies of the release process allow emphasizing an important role of the bulk aqueous medium in controlling the droplet to droplet fluorophore transfer and the attained equilibrium. The developed methodology could be applied to monitor release of other lipophilic dyes and it could help to better understand the cargo release from nanocarriers.

16.
Diabetes Metab Syndr Obes ; 13: 1473-1480, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32440176

RESUMEN

BACKGROUND AND OBJECTIVES: A drug repurposing strategy is an approach for identifying new therapeutic uses for approved or investigational drugs. Thanks to the moderate cost of repurposing a drug compared to bringing new chemical entity to the market, drug repurposing is rapidly gaining ground. The aim of this work is to study the anti-obesity effect of disulfiram (DSF), an irreversible aldehyde dehydrogenase inhibitor approved by the Food and Drug Administration (FDA) to treat chronic alcoholism since 1951. METHODS: Thirty male Albino rats were randomly assigned to six groups. G1, the control group, was given a standard diet. G2, the positive control group, was given a high-fat diet (HFD). G3 was given an HFD, and DSF 50 mg/kg/day was administered orally from day one for six weeks. G4 was given an HFD, and DSF 200 mg/kg/day was administered orally from day one for six weeks. G5 was given an HFD for six weeks; then treatment started with 50 mg/kg/day DSF orally. G6 was given an HFD for six weeks; then treatment started with 200 mg/kg/day DSF orally for three weeks. The body weight, food consumption and blood glucose levels were monitored over the given time interval. RESULTS: Both doses of DSF significantly limited the body weight gain caused by an HFD for the treated animals. HF-fed rats received 50 and 200 mg/kg/day of DSF had their body weight increased by 51.93 ± 7.89% and 20.88 ± 15.05% respectively, whereas the body weight of control animals increased by 93.1 ± 20.04%. DSF also significantly decreased the body weight of obese animals. At 50 and 200 mg/kg/day of DSF, HF-fed rats lost 16.74 ± 8.61% and 23.9 ± 3.93% respectively, as their untreated counterparts had their body weight increased by 11.85 ± 3.79% after three weeks of treatment, thus restoring a body weight matching those who received a standard diet. CONCLUSION: FDA-approved disulfiram has a strong anti-obesity effect on HFD-fed rats.

17.
Colloids Surf B Biointerfaces ; 191: 111010, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32315927

RESUMEN

The purpose of this study was to develop Pickering water-in-oil nano-emulsions only stabilized by Eudragit RL100 nanoparticles (NPs), in order to increase the nano-emulsion stability and create a barrier to improve the drug encapsulation and better control the drug release. The first part of this study was dedicated to investigating the nano-emulsion formulation by ultrasonication and understanding the interfacial behavior and role of NPs in the stabilization of the water/oil interface. The focus was on the surface coverage in the function of the formulation parameters (volume fractions) to disclose the extents and limitations of the process. The main physicochemical analysis of the Pickering nano-emulsions was performed by dynamic light scattering and transmission electron microscopy. On the other hand, the second experimental approach was dedicated to understanding the interfacial behavior of the Eudragit RL100 NPs toward a model water/oil interface, using a dynamic tensiometer with axisymmetric drop shape analysis. The study investigated the NPs' adsorption, as well as their rheological behavior. The aim of this part was to reveal the main phenomena that govern the interactions between NPs and the interface in order to understand the origin of Pickering nano-emulsions' stability. The last part of the study was concerned with the stability and in vitro release of a model encapsulated drug (ketoprofen) in a gastric and simulated intestinal environment. The results showed that Pickering nano-emulsions significantly improved the resistance to gastric pH, inducing a significantly slower drug release compared to classical nano-emulsions' stabilized surfactants. These Pickering nano-emulsions appear as a promising technology to modify the delivery of a therapeutic agent, in the function of the pH, and can be, for instance, applied to the oral drug delivery of poorly soluble drugs.


Asunto(s)
Resinas Acrílicas/química , Antiinflamatorios no Esteroideos/química , Sistemas de Liberación de Medicamentos , Cetoprofeno/química , Nanopartículas/química , Resinas Acrílicas/administración & dosificación , Administración Oral , Liberación de Fármacos , Emulsiones/administración & dosificación , Emulsiones/química , Nanopartículas/administración & dosificación , Tamaño de la Partícula , Solubilidad , Propiedades de Superficie
18.
Chem Pharm Bull (Tokyo) ; 67(12): 1324-1327, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31564698

RESUMEN

Phenanthroindolizidines are naturally occurring alkaloids mainly isolated from different species of Asclepiadaceae. These alkaloids are characterized by an excellent anticancer activity against a very wide range of cancerous cell lines including those who are multi drug resistant. Nevertheless, phenanthroindolizidines are associated with sever neurotoxicity that prevented any candidate from this family to pass the clinical trials. A number of boron-based analogues of (R)-6-O-desmethylantofine have been synthesised. Their physochemical properties were evaluated, same as their in-vitro antiproliferative activity. The pinacol boronate ester derivative (3) showed interesting cytotoxicity against a panel of cancerous cell lines attested by a cancer cell growth-inhibitory potency (GI50) as low as 30 nM.


Asunto(s)
Antineoplásicos/farmacología , Ácidos Borónicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Ácidos Borónicos/química , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Relación Estructura-Actividad , Células Tumorales Cultivadas
19.
Chem Pharm Bull (Tokyo) ; 67(11): 1208-1210, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31495803

RESUMEN

Co-drug, or mutual-prodrug, is a drug design approach consisting of covalently linking two active drugs so as to improve the pharmacokinetics and/or pharmacodynamics properties of one or both drugs. Co-drug strategy has proven good success in overcoming undesirable properties such as absorption, poor bioavailability, nonspecificity, and gastrointestine tract (GIT) side effects. In this work, we successfully developed a co-drug of 14-hydroxytylophorine, a phenanthroindolizidine derivative with remarkable antiproliferative activity, and dichloroacetate, a known inhibitor of pyruvate dehydrogenase kinase. Dichloroacetate steers tumour cell metabolism from glycolysis back to glucose oxidation, which in turn reverses the Warburg effect and renders tumour cells with a proliferative disadvantage. The obtained co-drugs retained the cytotoxicity of 14-hydroxytylophorine. However, they showed similar unselectivity towards normal cells.


Asunto(s)
Antineoplásicos/farmacología , Diseño de Fármacos , Indoles/farmacología , Fenantrenos/farmacología , Profármacos/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Células CHO , Línea Celular , Proliferación Celular/efectos de los fármacos , Cricetulus , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Indoles/síntesis química , Indoles/química , Estructura Molecular , Fenantrenos/síntesis química , Fenantrenos/química , Profármacos/síntesis química , Profármacos/química , Solubilidad , Relación Estructura-Actividad
20.
J Pharm Pharmacol ; 71(8): 1185-1198, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31049986

RESUMEN

OBJECTIVES: This review highlights both the physicochemical characteristics of the nanocarriers (NCs) and the physiological features of tumour microenvironment (TME) to outline what strategies undertaken to deliver the molecules of interest specifically to certain lesions. This review discusses these properties describing the convenient choice between passive and active targeting mechanisms with details, illustrated with examples of targeting agents up to preclinical research or clinical advances. KEY FINDINGS: Targeted delivery approaches for anticancers have shown a steep rise over the past few decades. Though many successful preclinical trials, only few passive targeted nanocarriers are approved for clinical use and none of the active targeted nanoparticles. Herein, we review the principles and for both processes and the correlation with the tumour microenvironment. We also focus on the limitation and advantages of each systems regarding laboratory and industrial scale. SUMMARY: The current literature discusses how the NCs and the enhanced permeation and retention effect impact the passive targeting. Whereas the active targeting relies on the ligand-receptor binding, which improves selective accumulation to targeted sites and thus discriminates between the diseased and healthy tissues. The latter could be achieved by targeting the endothelial cells, tumour cells, the acidic environment of cancers and nucleus.


Asunto(s)
Antineoplásicos/administración & dosificación , Antineoplásicos/química , Portadores de Fármacos/química , Nanopartículas/administración & dosificación , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Animales , Sistemas de Liberación de Medicamentos/métodos , Humanos , Microambiente Tumoral/efectos de los fármacos
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