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1.
Curr Issues Mol Biol ; 45(2): 1627-1643, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36826050

RESUMEN

The current study aimed to determine how palm date aqueous fruit extracts (AFE) affected the autistic-like behaviors brought on by valproic acid (VPA) injection, as well as any potential contributions from Sirt-1, oxidative stress, apoptosis, and autophagy. The pregnant Sprague Dawley females were treated with VPA at 12.5th gestation day and pregnant females and their offspring were treated with AFE orally at doses of 4 mg/Kg by gastric gavage for 45 days after birth. The elevated plus-T maze, water maze, and rotarod tests were used to examine autism-like behaviors. At the end of the study, the expression of Nrf2, heme oxygenase (HO-1), Sirt-1, caspase-3 (a marker of apoptosis), LC3 (a marker of autophagy), and NFκB (inflammatory cytokines) were evaluated along with the oxidative stress in brain tissues and the histological changes in the cerebellum and hippocampus. The neurobehavioral assessments significantly declined due to VPA, which also significantly increased oxidative stress in the brain tissues and significantly decreased Nrf2 and HO-1 expression. Additionally, VPA administration caused significant increase in the expression of caspase-3 in the cerebellar cortex, not in the hippocampus; LC3 and NFκB in the hippocampus, not in the cerebellar cortex; and significant reduction in the expression of Sirt-1 in the hippocampus, not in the cerebellum. On the other hand, AFE treatment significantly improved the neurobehavioral changes as well as it improved significantly the oxidative stress and the expression of LC3, NFκB, NrF2, HO-1, and Sirt-1 in the cerebellum and hippocampus. Conclusions: AFE administration might improve the autistic-like symptoms induced by VPA in rats via attenuation of the oxidative stress, upregulation of Nrf2 and HO-1, Sirt-1 and LC3 expression with downregulation of caspase-3, and NFκB expression in the cerebellum and hippocampus.

2.
Mol Pharm ; 20(2): 929-941, 2023 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-36592951

RESUMEN

Sodium caprate (C10) has been widely evaluated as an intestinal permeation enhancer for the oral delivery of macromolecules. However, the effect of C10 on the intestinal absorption of peptides with different physicochemical properties and its permeation-enhancing effect in vivo remains to be understood. Here, we evaluated the effects of C10 on intestinal absorption in rats with a glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GIP-GLP1) dual agonist peptide (LY) and semaglutide with different enzymatic stabilities and self-association behaviors as well as the oral exposure of the LY peptide in minipigs. Furthermore, we investigated the mechanism of action (MoA) of C10 for improving the intestinal absorption of the LY peptide in vivo via live imaging of the rat intestinal epithelium and tissue distribution of the LY peptide in minipigs. The LY peptide showed higher proteolytic stability in pancreatin and was a monomer in solution compared to that in semaglutide. C10 increased in vitro permeability in the minipig intestinal organoid monolayer to a greater extent for the LY peptide than for semaglutide. In the rat jejunal closed-loop model, C10 increased the absorption of LY peptide better than that of semaglutide, which might be attributed to higher in vitro proteolytic stability and permeability of the LY peptide. Using confocal live imaging, we observed that C10 enabled the rapid oral absorption of a model macromolecule (FD4) in the rat intestine. In the duodenum tissues of minipigs, C10 was found to qualitatively reduce the tight junction protein level and allow peptide uptake to the intestinal cells. C10 decreased the transition temperature of the artificial lipid membrane, indicating an increase in membrane fluidity, which is consistent with the above in vivo imaging results. These data indicated that the LY's favorable physicochemical properties combined with the effects of C10 on the intestinal mucosa resulted in an ∼2% relative bioavailability in minipigs.


Asunto(s)
Polipéptido Inhibidor Gástrico , Péptido 1 Similar al Glucagón , Porcinos , Ratas , Animales , Polipéptido Inhibidor Gástrico/metabolismo , Polipéptido Inhibidor Gástrico/farmacología , Péptido 1 Similar al Glucagón/metabolismo , Porcinos Enanos/metabolismo , Ácidos Decanoicos/farmacología , Absorción Intestinal , Mucosa Intestinal/metabolismo , Péptidos/metabolismo
3.
Pharm Res ; 39(10): 2555-2567, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36050547

RESUMEN

PURPOSE: Oral delivery of therapeutic peptides has been challenging due to multiple physiological factors and physicochemical properties of peptides. We report a systematic approach to identify formulation compositions combining a permeation enhancer and a peptidase inhibitor that minimize proteolytic degradation and increase absorption of a peptide across the small intestine. METHODS: An acylated glucagon-like peptide-1/glucagon co-agonist peptide (4.5 kDa) was selected as a model peptide. Proteolytic stability of the peptide was investigated in rat and pig SIF. Effective PEs and multiple component formulations were identified in rats. Relative bioavailability of the peptide was determined in minipigs via intraduodenal administration (ID) of enteric capsules. RESULTS: The peptide degraded rapidly in the rat and pig SIF. Citric acid, SBTI, and SBTCI inhibited the enzymatic degradation. The peptide self-associated into trimers in solution, however, addition of PEs monomerized the peptide. C10 was the most effective PE among tested PEs (DPC, LC, rhamnolipid, C12-maltosides, and SNAC) to improve intestinal absorption of the peptide in the rat IJ-closed loop model. A combination of C10 and SBTI or SBTCI increased the peptide exposure 5-tenfold compared to the exposure with the PE alone in the rat IJ-cannulated model, and achieved 1.06 ± 0.76% bioavailability in minipigs relative to subcutaneous via ID administration using enteric capsules. CONCLUSION: We identified SBTI and C10 as an effective peptidase inhibitor and PE for intestinal absorption of the peptide. The combination of SBTI and C10 addressed the peptide physiochemical properties and provides a formulation strategy to achieve intestinal delivery of this peptide.


Asunto(s)
Péptido 1 Similar al Glucagón , Glucagón , Animales , Cápsulas , Ácido Cítrico , Absorción Intestinal , Péptido Hidrolasas , Péptidos/farmacología , Inhibidores de Proteasas , Ratas , Porcinos , Porcinos Enanos/metabolismo
4.
Am J Nephrol ; 51(4): 327-336, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32160625

RESUMEN

BACKGROUND: The benefits of treating anti-neutrophil cytoplasmic autoantibody-associated vasculitis (AAV) in advancing age remains unclear with most published studies defining elderly as ≥65 years. This study aims to determine outcomes of induction immunosuppression in patients aged ≥75 years. METHODS: A cohort of patients aged ≥75 years with a diagnosis of AAV between 2006 and 2018 was constructed from 2 centres. Follow-up was to 2 years or death. Analysis included multivariable Cox regression to compare mortality and end-stage renal disease (ESRD) based on receipt of induction immunosuppression therapy with either cyclophosphamide or rituximab. A systematic review of outcome studies was subsequently undertaken amongst this patient group through Pubmed, Cochrane and Embase databases from inception until October 16, 2019. RESULTS: Sixty-seven patients were identified. Mean age was 79 ± 2.9 years and 82% (n = 55) received induction immunosuppression. Following systematic review, 4 studies were eligible for inclusion, yielding a combined total of 290 patients inclusive of our cohort. The aggregated 1-year mortality irrespective of treatment was 31% (95% CI 25-36%). Within our cohort, induction immunosuppression therapy was associated with a significantly lower 2-year mortality risk (hazard ratio [HR] 0.29 [95% CI 0.09-0.93]). The pooled HR by meta-analysis confirmed this with a significant risk reduction for death (HR 0.31 [95% CI 0.16-0.57], I2 = 0%). Treated patients had a lower pooled rate of ESRD, but was not statistically significant (HR 0.71 [95% CI 0.15-3.35]). CONCLUSION: This meta-analysis suggests that patients ≥75 years with AAV do benefit from induction immunosuppression with a significant survival benefit. Age alone should not be a limiting factor when considering treatment.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/tratamiento farmacológico , Inmunosupresores/uso terapéutico , Fallo Renal Crónico/tratamiento farmacológico , Factores de Edad , Anciano , Anciano de 80 o más Años , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/complicaciones , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/inmunología , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/mortalidad , Toma de Decisiones Clínicas , Humanos , Fallo Renal Crónico/inmunología , Fallo Renal Crónico/mortalidad , Inducción de Remisión/métodos , Medición de Riesgo/estadística & datos numéricos , Resultado del Tratamiento
5.
Nephrol Dial Transplant ; 35(12): 2172-2182, 2020 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-31981353

RESUMEN

BACKGROUND: Accurate comparisons of haemodialysis (HD) and peritoneal dialysis (PD) survival based on observational studies are difficult due to substantial residual confounding that arises from imbalances between treatments. Propensity score matching (PSM) comparisons confer additional advantages over conventional methods of adjustment by further reducing selection bias between treatments. We conducted a systematic review of studies that compared mortality between in-centre HD with PD using a PSM-based approach. METHODS: A sensitive search strategy identified all citations in the PubMed, Cochrane and EMBASE databases from inception through November 2018. Pooled PD versus HD mortality hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated through random-effects meta-analysis. A subsequent meta-regression explored factors to account for between-study variation. RESULTS: The systematic review yielded 214 citations with 17 cohort studies and 113 578 PSM incident dialysis patients. Cohort periods spanned the period 1993-2014. The pooled HR for PD versus HD was 1.06 (95% CI 0.99-1.14). There was considerable variation by country, however, mortality risks for PD versus HD remained virtually unchanged when stratified by geographical region with HRs of 1.04 (95% CI 0.94-1.15), 1.14 (95% CI 0.99-1.32) and 0.98 (0.87-1.10) for European, Asian and American cohorts, respectively. Subgroup meta-analyses revealed similar risks for patients with diabetes [HR 1.09 (95% CI 0.98-1.21)] and without diabetes [HR 0.99 (95% CI 0.90-1.09)]. Heterogeneity was substantial (I2 = 87%) and was largely accounted for by differences in cohort period, study type and country of origin. Together these factors explained a substantial degree of between-studies variance (R2 = 90.6%). CONCLUSIONS: This meta-analysis suggests that PD and in-centre HD carry equivalent survival benefits. Reported differences in survival between treatments largely reflect a combination of factors that are unrelated to clinical efficacy.


Asunto(s)
Fallo Renal Crónico/mortalidad , Diálisis Peritoneal/mortalidad , Diálisis Renal/mortalidad , Humanos , Fallo Renal Crónico/terapia , Pronóstico , Puntaje de Propensión , Tasa de Supervivencia
6.
Nephrol Dial Transplant ; 35(3): 447-457, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30099517

RESUMEN

BACKGROUND: Complete ascertainment of the true rates of acute kidney injury (AKI) and emerging trends are essential for planning of preventive strategies within health systems. METHODS: We conducted a retrospective cohort study from 2005 to 2014 using data from regional laboratory information systems to determine incidence rates of AKI and severity Stages 1-3 in the Irish health system. Multivariable models were developed to explore annual trends and the contributions of demographic factors, clinical measures, geographic factors and location of medical supervision expressed as adjusted odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: From 2005 to 2014, incidence rates of AKI increased from 6.1% (5.8-6.3) to 13.2% (12.7-13.8) per 100 patient-years in men and from 5.0% (4.8-5.2) to 11.5% (11.0-12.0) in women, P < 0.001. Stage 1 AKI accounted for the greatest growth in incidence, from 4.4% (95% CI 4.3-4.6) in 2005 to 10.1% (95% CI 9.8-10.5) in 2014 (P < 0.001 for trend). Compared with 2005, patients in 2014 were more likely to experience AKI [OR 4.53 (95% CI 4.02-5.1) for Stage 1, OR 5.22 (4.16-6.55) for Stage 2 and OR 4.11 (3.05-5.54) for Stage 3], adjusting for changing demographic and clinical profiles. Incidence rates of AKI increased in all locations of medical supervision during the period of observation, but were greatest for inpatient [OR 19.11 (95% CI 17.69-20.64)] and emergency room settings [OR 5.97 (95% CI 5.56-6.42)] compared with a general practice setting (referent). CONCLUSION: Incidence rates of AKI have increased substantially in the Irish health system, which were not accounted for by changing demographic patterns, clinical profiles or location of medical supervision.


Asunto(s)
Lesión Renal Aguda/epidemiología , Bases de Datos Factuales/estadística & datos numéricos , Índice de Severidad de la Enfermedad , Lesión Renal Aguda/etiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Incidencia , Irlanda/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
7.
Pharm Res ; 36(6): 89, 2019 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-31004235

RESUMEN

PURPOSE: To develop a planar, asymmetric, micro-scale oral drug delivery vehicle by i) fabricating microdevice bodies with enteric materials, ii) efficiently and stably loading sensitive drug molecules, and iii) capping microdevices for controlled drug release. METHODS: Picoliter-volume inkjet printing was used to fabricate microdevices through additive manufacturing via drop-by-drop deposition of enteric polymer materials. Microdevice bodies with reservoirs are fabricated through deposition of an enteric polymer, Eudragit FS 30 D. A model API, insulin, was loaded into each microdevice and retained its stability during printing and release. Eudragit L 100 and/or S 100 were used to cap microdevices and control the kinetics of insulin release in simulated intestinal conditions. RESULTS: Microdevice morphologies and size can be tuned on the fly based on printing parameters to span from the microscale to the mesoscale. Insulin retained its stability throughout device fabrication and during in vitro release in simulated intestinal conditions. Insulin release kinetics, from burst release to no release, can be tailored by controlling the blend of the Eudragit capping material. CONCLUSION: This approach represents a uniquely scalable and flexible strategy for microdevice fabrication that overcomes limitations in loading sensitive biologics and in the tuneability of device geometries that are inherent to traditional microfabrication strategies.


Asunto(s)
Preparaciones de Acción Retardada/química , Sistemas de Liberación de Medicamentos/instrumentación , Diseño de Equipo/instrumentación , Insulinas/química , Polivinilos/química , Administración Oral , Preparaciones de Acción Retardada/administración & dosificación , Liberación de Fármacos , Excipientes/química , Insulinas/administración & dosificación , Microesferas , Tamaño de la Partícula , Impresión Tridimensional , Propiedades de Superficie
9.
Pharm Res ; 34(10): 2197-2210, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28721446

RESUMEN

PURPOSE: This report describes the effect of rhamnolipids (RLs) on the tight junctions (TJ) of the intestinal epithelium using the rat in-situ closed loop model. METHODS: We investigated the transport of 5 (6)-carboxyfluorescein (CF) and fluorescein isothiocyanate-labeled dextrans with average molecular weights of 4.4 and 10 kDa (FD-4 and FD-10) when co-administered with different concentrations of RLs. Lactate dehydrogenase (LDH) leakage assay and histopathological examination of treated intestinal loops were used to assess potential toxicity of RLs. Further, the effect of kaempferol on accelerating the resealing of the tight junctions in vivo was also investigated RESULTS: Data shows that administration of different RLs concentrations (1.0-5.0% v/v) increased CF absorption through rat intestine by 2.84- and 15.82-folds with RLs concentrations of 1.0% and 5.0% v/v, respectively. RLs exhibited size-dependent increase on FD-4 and FD-10 absorption. Dosing RLs at 1.0% v/v didn't cause a significant LDH leakage or histopathological changes to intestinal mucosa compared to higher concentrations, which showed a progressive damaging effect. Using kaempferol, a natural flavonoid that stimulates the assembly of the TJs, proved to enhance the recovery of barrier properties of the intestinal mucosa treated with high concentrations of RLs (2.5% and 5% v/v). CONCLUSIONS: These results collectively illustrate the ability of RLs to enhance oral bioavailability of different molecules across the intestinal epithelial membrane in a concentration- and time-dependent fashion.


Asunto(s)
Glucolípidos/metabolismo , Quempferoles/metabolismo , Administración Oral , Animales , Disponibilidad Biológica , Colorantes Fluorescentes/química , Glucolípidos/administración & dosificación , Glucolípidos/química , Humanos , Absorción Intestinal , Mucosa Intestinal/metabolismo , Quempferoles/administración & dosificación , Quempferoles/química , Masculino , Peso Molecular , Permeabilidad , Ratas , Ratas Wistar
10.
J Am Soc Nephrol ; 27(2): 580-93, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26429920

RESUMEN

The association of adult height with mortality has been extensively investigated in the general population, but little is known about this relationship among dialysis patients. We explored the relationship between height and mortality in a retrospective cohort study of 1,171,842 adults who began dialysis in the United States from 1995 to 2008 and were followed until December 31, 2010. We evaluated height-mortality associations in sex-specific quintiles of increasing height (Q1-Q5) using multivariable Cox regression models adjusted for demographics, comorbid conditions, lifestyle and disability indicators, socioeconomic status, and body weight. For men, compared with the referent quintile (Q1 <167 cm), successive height quintiles had significantly increased hazard ratios (HRs [95% confidence interval]) for mortality: 1.04 (1.02-1.06), 1.08 (1.06-1.10), 1.12 (1.11-1.14), and 1.18 (1.16-1.20) for Q2-Q5, respectively. For women (referent Q1 <155 cm), HRs for mortality were 1.00 (0.99-1.02), 1.05 (1.03-1.06), 1.05 (1.03-1.07), and 1.08 (1.06-1.10) for Q2-Q5, respectively. However, stratification by race showed the pattern of association differed significantly by race (P<0.001 for interaction). For black men, unlike other race groups, height only associated with mortality in Q5, with an HR of 1.06 (1.02-1.09). For black women, HRs for mortality were 0.94 (0.91-0.97), 0.98 (0.95-1.02), 0.96 (0.93-0.99), and 0.99 (0.96-1.02) for Q2-Q5, respectively. These results indicate tallness is associated with higher mortality risks for adults starting dialysis, but this association did not extend to black patients.


Asunto(s)
Estatura , Fallo Renal Crónico/mortalidad , Grupos Raciales , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo , Factores Sexuales
11.
Mol Pharm ; 13(4): 1413-29, 2016 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-26977718

RESUMEN

We report the synthesis of an amphiphilic triblock copolymer composed of a hydrophilic poly(ethylene glycol) (PEG) block, a central poly(acrylic acid) (PAA) block, and a hydrophobic poly(methyl methacrylate) (PMMA) block using atom transfer radical polymerization technique. We examined the self-assembly of PEG-b-PAA-b-PMMA copolymers in aqueous solutions forming nanosized micelles and their ability to encapsulate hydrophobic guest molecules such as Nile Red (NR) dye and cabazitaxel (CTX, an anticancer drug). We used 2,2ß'-(propane-2,2-diylbis(oxy))-diethanamine to react with the carboxylic acid groups of the central PAA block forming acid-labile, shell cross-linked micelles (SCLM). We investigated the loading efficiency and release of different guest molecules from non-cross-linked micelles (NSCLM) and shell cross-linked micelles (SCLM) prepared by reacting 50% (SCLM-50) and 100% (SCLM-100) of the carboxylic acid groups in the PAA in physiologic (pH 7.4) and acidic (pH 5.0) buffer solutions as a function of time. We examined the uptake of NR-loaded NSCLM, SCLM-50, and SCLM-100 micelles into PC-3 and C4-2B prostate cancer cells and the effect of different micelle compositions on membrane fluidity of both cell lines. We also investigated the effect of CTX-loaded NSCLM, SCLM-50, and SCLM-100 micelles on the viability of PC-3 and C4-2B cancer cells compared to free CTX as a function of drug concentration. Results show that PEG-b-PAA-b-PMMA polymers form micelles at concentrations ≥11 µg/mL with an average size of 40-50 nm. CTX was encapsulated in PEG-b-PAA-b-PMMA micelles with 55% loading efficiency in NSCLM. In vitro release studies showed that 30% and 85% of the loaded CTX was released from SCLM-50 micelles in physiologic (pH 7.4) and acidic (pH 5.0) buffer solutions over 30 h, confirming micelles' sensitivity to solution pH. Results show uptake of NSCLM and SCLM into prostate cancer cells delivering their chemotherapeutic cargo, which triggered efficient cancer cell death. PEG-b-PAA-b-PMMA micelles were not hemolytic and did not cause platelet aggregation, which indicate their biocompatibility.


Asunto(s)
Micelas , Taxoides/administración & dosificación , Taxoides/metabolismo , Línea Celular , Línea Celular Tumoral , Células Cultivadas , Humanos , Concentración de Iones de Hidrógeno , Macrófagos/metabolismo , Masculino , Neoplasias de la Próstata/metabolismo , Taxoides/efectos adversos
12.
Mol Pharm ; 13(12): 4054-4065, 2016 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-27696857

RESUMEN

We have developed acoustically activated nanodroplets (NDs) using an amphiphilic triblock copolymer, which self-assembles and encapsulates different perfluorocarbons including perfluoropentane (PFP) and perfluorohexane (PFH). Applying histotripsy pulses (i.e., short, high pressure, ultrasound pulses) to solutions of PFP- and PFH-NDs generated bubble clouds at a significantly reduced acoustic pressure compared to the cavitation pressure observed for histotripsy treatment alone. In this report, we summarize the results of combining histotripsy at low frequency (345 and 500 kHz) with PFP-NDs and PFH-NDs on the ablation of PC-3 and C4-2B prostate cancer cells. Using custom built histotripsy transducers coupled to a microscope and a high speed recording camera, we imaged the generation of a cavitation bubble cloud in response to different ultrasound regimes in solution and in tissue-mimicking gel phantoms. We quantified the associated ablation of individual cancer cells and 3D spheroids suspended in solution and embedded in tissue phantoms to compare the ablative capacity of PFP-NDs and PFH-NDs. Results show that histotripsy pulses at high acoustic pressure (26.2 MPa) ablated 80% of prostate cancer spheroids embedded in tissue-mimicking gel phantoms. In comparison, combining histotripsy pulses at a dramatically lower acoustic pressure (12.8 MPa) with PFP-NDs and PFH-NDs caused an ablation of 40% and 80% of the tumor spheroid volumes, respectively. These results show the potential of acoustically activated NDs as an image-guided ablative therapy for solid tumors and highlight the higher ablative capacity of PFH-NDs, which correlates with the boiling point of the encapsulated PFH and the stability of the formed bubble cloud.


Asunto(s)
Fluorocarburos/química , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Nanopartículas/química , Polímeros/química , Neoplasias de la Próstata/terapia , Esferoides Celulares/efectos de la radiación , Supervivencia Celular/efectos de los fármacos , Fluorocarburos/efectos de la radiación , Humanos , Masculino , Fantasmas de Imagen , Polímeros/efectos de la radiación , Esferoides Celulares/patología , Células Tumorales Cultivadas
13.
Mol Pharm ; 13(3): 895-906, 2016 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-26751280

RESUMEN

The endothelial cells lining the capillaries supplying the brain with oxygen and nutrients form a formidable barrier known as the blood-brain barrier (BBB), which exhibits selective permeability to small drug molecules and virtually impermeable to macromolecular therapeutics. Current in vitro BBB models fail to replicate this restrictive behavior due to poor integration of the endothelial cells with supporting cells (pericytes and astrocytes) following the correct anatomical organization observed in vivo. We report the coculture of mouse brain microvascular endothelial cells (b.End3), pericytes, with/without C8-D1A astrocytes in layered microfluidic channels forming three-dimensional (3D) bi- and triculture models of the BBB. The live/dead assay indicated high viability of all cultured cells up to 21 days. Trans-endothelial electrical resistance (TEER) values confirmed the formation of intact monolayers after 3 days in culture and showed statistically higher values for the triculture model compared to the single and biculture models. Screening the permeability of [(14)C]-mannitol and [(14)C]-urea showed the ability of bi- and triculture models to discriminate between different markers based on their size. Further, permeability of [(14)C]-mannitol across the triculture model after 18 days in culture matched its reported permeability across the BBB in vivo. Mathematical calculations also showed that the radius of the tight junctions pores (R) in the triculture model is similar to the reported diameter of the BBB in vivo. Finally, both the bi- and triculture models exhibited functional expression of the P-glycoprotein efflux pump, which increased with the increase in the number of days in culture. These results collectively indicate that the triculture model is a robust in vitro model of the BBB.


Asunto(s)
Astrocitos/citología , Barrera Hematoencefálica , Encéfalo/citología , Endotelio Vascular/citología , Pericitos/citología , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Animales , Astrocitos/metabolismo , Encéfalo/metabolismo , Permeabilidad Capilar , Técnicas de Cultivo de Célula , Permeabilidad de la Membrana Celular , Técnicas de Cocultivo , Endotelio Vascular/metabolismo , Técnicas In Vitro , Ratones , Microfluídica , Pericitos/metabolismo
14.
Mol Pharm ; 12(7): 2406-17, 2015 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-26020100

RESUMEN

Rho-GTPases are small GTP-binding proteins that contribute to the epithelial-to-mesenchymal transition by regulating several cellular processes including organization of the actin cytoskeleton, cell motility, transcription, and cell proliferation. Overexpression of RhoC-GTPases (RhoC) in breast cancer has been implicated in poor disease prognosis due to increased cancer cells invasion, migration, and motility, which warranted its consideration as a therapeutic target for inhibiting breast cancer metastasis. Using silencing RNA (siRNA) molecules to knockdown RhoC expression is a promising approach to inhibit breast cancer metastases. However, transforming anti-RhoC siRNA molecules into a viable therapy remains a challenge due to the lack of a biocompatible carrier that can selectively deliver the RNA cargo into breast cancer cells. We report the use of a degradable, pH-sensitive, ß-cyclodextrin (ßCD)-based polymeric carrier that condenses anti-RhoC siRNA forming "smart" particles. These smart anti-RhoC particles were efficiently internalized, successfully escaped the endosome, and delivered the RNA cargo into the cytoplasm of SUM149 and MDA-MB-231 breast cancer cells. Our results show that anti-RhoC particles used at a low N/P ratio of 2.5/1 suppressed RhoC protein levels by 100% and 90% in SUM149 and MDA-MB-231 cells, respectively. Further, anti-RhoC particles inhibited the invasion, motility, and migration of SUM149 and MDA-MB-231 cells by 40-47%, 57-60%, and 61.5-73%, respectively. Smart particles encapsulating the scrambled siRNA sequence did not affect RhoC protein expression or the invasion, motility, and migration of SUM149 and MDA-MB-231 cells, which indicate the biocompatibility of the polymeric carrier and selectivity of the observed RhoC knockdown. These results collectively indicate the therapeutic potential of smart anti-RhoC particles in arresting the metastatic spread of breast cancer cells.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Movimiento Celular/efectos de los fármacos , Citoplasma/metabolismo , Nanopartículas/administración & dosificación , Invasividad Neoplásica/prevención & control , Interferencia de ARN/fisiología , Proteínas de Unión al GTP rho/genética , Neoplasias de la Mama/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Invasividad Neoplásica/genética , ARN Interferente Pequeño/genética , Proteína de Unión al GTP rhoA/genética , Proteína rhoC de Unión a GTP
16.
Pharm Res ; 31(4): 887-94, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24065598

RESUMEN

PURPOSE: This report describes the effect of rhamnolipids (RLs), an amphiphilic biosurfactant produced by the bacterium Pseudomonas aeruginosa, on the integrity and permeability across Caco-2 cell monolayers. METHODS: We measured the trans-epithelial electrical resistance (TEER) and permeability of [(14)C]mannitol across Caco-2 cell monolayers upon incubation with 0.01-5.0% v/v RLs as a function of incubation time (30, 60, 90, and 120 min). We also studied the recovery of RL-treated Caco-2 cell monolayers upon incubation with Kaempferol, which is a natural flavonoid that promotes the assembly of the tight junctions. RESULTS: TEER of Caco-2 cell monolayers incubated with 0.01-5.0% v/v RLs solution dropped to 80-28% of that of untreated cells. Decline in TEER was associated with an increase in [(14)C]mannitol permeability as a function of RLs concentration and incubation time with Caco-2 cells. Incubation of RLs-treated Caco-2 cell monolayers with normal culture medium for 48 h did not restore barrier integrity. Whereas, incubation of a RLs-treated Caco-2 cells with culture medium containing Kaempferol for 24 h restored barrier function indicated by the higher TEER and lower [(14)C]mannitol permeability values. CONCLUSIONS: These results show the ability of RLs to modulate the integrity and permeability of Caco-2 cell monolayers in a concentration- and time-dependent fashion, which suggest their potential to function as a non-toxic permeation enhancer.


Asunto(s)
Permeabilidad de la Membrana Celular/fisiología , Glucolípidos/metabolismo , Glucolípidos/farmacología , Uniones Estrechas/metabolismo , Células CACO-2 , Permeabilidad de la Membrana Celular/efectos de los fármacos , Humanos , Quempferoles/farmacología , Permeabilidad/efectos de los fármacos , Uniones Estrechas/efectos de los fármacos
17.
Cureus ; 16(1): e53212, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38425633

RESUMEN

Sleep paralysis (SP) is a mixed state of consciousness and sleep, combining features of rapid eye movement (REM) sleep with those of wakefulness. The exact cause of SP is unknown, and its prevalence varies among the studies. We aim to identify SP's global prevalence, the affected population's characteristics, and the SP's clinical picture. We searched three databases (PubMed, Scopus, and Web of Science (WoS)) using a unique search strategy to identify eligible studies. All observational studies identifying the prevalence or frequency of sleeping paralysis were included. No exclusions are made based on country, race, or questionnaire. The analysis was performed using the latest version of R software (R Core Team, Vienna, Austria). The analysis included 76 studies from 25 countries with 167,133 participants. The global prevalence of SP was 30% (95% CI (22%, 39%)). There were similar frequencies of isolated SP and SP (33%, 95% CI (26%, 42%), I2 = 97%, P <0.01; 31%, 95% CI (21%, 43%), I2 = 100%, P = 0, respectively). A subgroup analysis showed that the majority of those who experienced SP were psychiatric patients (35%, 95% CI (20%, 55%), I2 = 96%, P <0.01). The prevalence among non-psychiatric patients was among students (34%, 95% CI (23%, 47%), I2 = 100%, P = 0). Auditory and visual hallucinations were reported in 24.25% of patients. Around 4% had only visual hallucinations. Meta-regression showed no association between the frequency of SP and sex. Publication bias was detected among the included studies through visual inspection of funnel plot asymmetry. Our findings revealed that 30% of the population suffered from SP, especially psychiatric patients and students. The majority of SP cases lacked associated hallucinations, while a noteworthy proportion experienced combined visual and auditory hallucinations.

18.
Arch Public Health ; 82(1): 28, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38449000

RESUMEN

BACKGROUND: Excessive or inappropriate use of social media has been linked to disruptions in regular work, well-being, mental health, and overall reduction of quality of life. However, a limited number of studies documenting the impact of social media on health-related quality of life (HRQoL) are available globally. AIM: This study aimed to explore the perceived social media needs and their impact on the quality of life among the adult population of various selected countries. METHODOLOGY: A cross-sectional, quantitative design and analytical study utilized an online survey disseminated from November to December 2021. RESULTS: A total of 6689 respondents from ten countries participated in the study. The largest number of respondents was from Malaysia (23.9%), followed by Bangladesh (15.5%), Georgia (14.8%), and Turkey (12.2%). The prevalence of social media users was over 90% in Austria, Georgia, Myanmar, Nigeria, and the Philippines. The majority of social media users were from the 18-24 age group. Multiple regression analysis showed that higher education level was positively correlated with all four domains of WHOQoL. In addition, the psychological health domain of quality of life was positively associated in all countries. Predictors among Social Media Needs, Affective Needs (ß = -0.07), and Social Integrative Needs (ß = 0.09) were significantly associated with psychological health. CONCLUSION: The study illuminates the positive correlation between higher education levels and improved life quality among social media users, highlighting an opportunity for policymakers to craft education-focused initiatives that enhance well-being. The findings call for strategic interventions to safeguard the mental health of the global social media populace, particularly those at educational and health disadvantages.

19.
Mol Pharm ; 10(7): 2730-8, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23734725

RESUMEN

B-cell lymphoma 2 (Bcl-2) is an antiapoptotic protein that is overexpressed in head and neck squamous cell carcinomas, which has been implicated in development of radio- and chemoresistance. Small molecule inhibitors such as AT-101 (a BH3-mimetic drug) have been developed to inhibit the antiapoptotic activity of Bcl-2 proteins, which proved effective in restoring radio- and chemo-sensitivity in head and neck cancer cells. However, high doses of AT-101 are associated with gastrointestinal, hepatic, and fertility side effects, which prompted the search for other Bcl-2 inhibitors. Short interfering RNA (siRNA) proved to inhibit antiapoptotic Bcl-2 protein expression and trigger cancer cell death. However, transforming siRNA molecules into a viable therapy remains a challenge due to the lack of efficient and biocompatible carriers. We report the development of degradable star-shaped polymers that proved to condense anti-Bcl-2 siRNA into "smart" pH-sensitive and membrane-destabilizing particles that shuttle their cargo past the endosomal membrane and into the cytoplasm of head and neck cancer cells. Results show that "smart" anti-Bcl-2 particles reduced the mRNA and protein levels of antiapoptotic Bcl-2 protein in UM-SCC-17B cancer cells by 50-60% and 65-75%, respectively. Results also show that combining "smart" anti-Bcl-2 particles with the IC25 of AT-101 (inhibitory concentration responsible for killing 25% of the cells) synergistically inhibits cancer cell proliferation and increases cell apoptosis, which reduce the survival of UM-SCC-17B cancer cells compared to treatment with AT-101 alone. Results indicate the therapeutic benefit of combining siRNA-mediated knockdown of antiapoptotic Bcl-2 protein expression with low doses of AT-101 for inhibiting the growth of head and neck cancer cells.


Asunto(s)
Gosipol/análogos & derivados , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/patología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Apoptosis/genética , Apoptosis/fisiología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Gosipol/farmacología , Neoplasias de Cabeza y Cuello/genética , Humanos , Proteínas Proto-Oncogénicas c-bcl-2/genética , Interferencia de ARN/fisiología , ARN Interferente Pequeño
20.
Clin Kidney J ; 16(5): 768-772, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37151424

RESUMEN

While electrolyte disorders are common in nephrologists' clinical practice, hypothermia is a condition that nephrologists rarely encounter. Hypothermia can induce several pathophysiological effects on the human body, including hypokalaemia, which is reversible with rewarming. Despite growing evidence from animal research and human studies, the underlying mechanisms of hypothermia-induced hypokalaemia remain unclear. Boubes and colleagues recently presented a case series of hypokalaemia during hypothermia and rewarming, proposing a novel hypothesis for the underlying mechanisms. In this editorial, we review the current knowledge about hypothermia and associated electrolyte changes with insights into the effects of hypothermia on renal physiology.

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