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1.
J Nutr ; 150(2): 276-284, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31616932

RESUMEN

BACKGROUND: Avocados are a nutrient-dense source of MUFAs and are rich in antioxidants. Avocados have an additional LDL cholesterol (LDL-C) lowering effect beyond that observed when their MUFAs are substituted for SFAs, especially on small, dense LDL (sdLDL) particles, which are susceptible to in vivo oxidation and associated with increased risk of cardiovascular disease (CVD). OBJECTIVES: We investigated whether a healthy diet with 1 avocado daily decreased the following secondary outcomes: circulating oxidized LDL (oxLDL) and related oxidative stress markers. METHODS: A randomized, crossover, controlled feeding trial was conducted with 45 men and women, aged 21-70 y, with overweight or obesity and elevated LDL-C (25th-90th percentile). Three cholesterol-lowering diets were provided (5 wk each) in random sequences: a lower-fat (LF) diet (24% calories from fat-7% SFAs, 11% MUFAs, 6% PUFAs) and 2 moderate-fat (MF) diets (34% calories from fat-6% SFAs, 17% MUFAs, 9% PUFAs): the avocado (AV) diet included 1 Hass avocado (∼136 g) per day, and the MF diet used high oleic acid oils to match the fatty acid profile of 1 avocado. A general linear mixed model was used to analyze the treatment effects. RESULTS: Compared with baseline, the AV diet significantly decreased circulating oxLDL (-7.0 U/L, -8.8%, P = 0.0004) and increased plasma lutein concentration (19.6 nmol/L, 68.7%, P < 0.0001), and both changes differed significantly from that after the MF and LF diets (P ≤ 0.05). The change in oxLDL caused by the AV diet was significantly correlated with the changes in the number of sdLDL particles (r = 0.32, P = 0.0002) but not large, buoyant LDL particles. CONCLUSIONS: One avocado a day in a heart-healthy diet decreased oxLDL in adults with overweight and obesity, and the effect was associated with the reduction in sdLDL. This trial was registered at http://www.clinicaltrials.gov as NCT01235832.


Asunto(s)
Antioxidantes/metabolismo , Grasas de la Dieta/administración & dosificación , Lipoproteínas LDL/metabolismo , Obesidad/metabolismo , Sobrepeso/metabolismo , Persea , Adulto , Anciano , Biomarcadores/metabolismo , Estudios Cruzados , Femenino , Humanos , Mediadores de Inflamación/metabolismo , Lipoproteínas LDL/química , Masculino , Persona de Mediana Edad , Oxidación-Reducción , Estrés Oxidativo , ARN Mensajero/genética , Vitaminas/metabolismo , Adulto Joven
2.
Bioconjug Chem ; 28(7): 1878-1892, 2017 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-28581724

RESUMEN

A series of zinc(II) dipicolylamine (ZnDPA)-based drug conjugates have been synthesized to probe the potential of phosphatidylserine (PS) as a new antigen for small molecule drug conjugate (SMDC) development. Using in vitro cytotoxicity and plasma stability studies, PS-binding assay, in vivo pharmacokinetic studies, and maximum tolerated dose profiles, we provided a roadmap and the key parameters required for the development of the ZnDPA based drug conjugate. In particular, conjugate 24 induced tumor regression in the COLO 205 xenograft model and exhibited a more potent antitumor effect with a 70% reduction of cytotoxic payload compared to that of the marketed irinotecan when dosed at the same regimen. In addition to the validation of PS as an effective pharmacodelivery target for SMDC, our work also provided the foundation that, if applicable, a variety of therapeutic agents could be conjugated in the same manner to treat other PS-associated diseases.


Asunto(s)
Antineoplásicos/farmacocinética , Inmunoconjugados/uso terapéutico , Terapia Molecular Dirigida/métodos , Compuestos Organometálicos/inmunología , Fosfatidilserinas/inmunología , Ácidos Picolínicos/inmunología , Animales , Antineoplásicos/síntesis química , Línea Celular Tumoral , Humanos , Inmunoconjugados/química , Inmunoconjugados/farmacocinética , Compuestos Organometálicos/síntesis química , Compuestos Organometálicos/farmacología , Fosfatidilserinas/metabolismo , Ácidos Picolínicos/síntesis química , Ácidos Picolínicos/farmacología , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de Xenoinjerto
3.
J Nutr ; 147(5): 746-753, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28298542

RESUMEN

Background: The use of parenteral nutrition formulas is often associated with the development of hepatic steatosis. We have shown previously that the addition of a lipid emulsion (LE) rich in n-6 (ω-6) fatty acids (FAs) ameliorated triglyceride (TG) accumulation in the livers of nonobese mice fed a high-carbohydrate diet (HCD) for 5 wk. However, it remains unclear how rapidly this condition develops and whether it can be prevented by LE with or without a running wheel for voluntary exercise (Exe).Objective: We investigated in an 8-d study whether mice develop steatosis and whether the administration of LE with or without Exe reduces the concentration of total FAs and prevents an increase in the expression of genes in the liver associated with lipogenesis.Methods: Male C57BL/6 mice aged 5 wk were randomized into 5 groups: standard feed pellet (SFP); a liquid HCD (77% of total energy from carbohydrates and 0.5% from fat); HCD + Exe; HCD + 13.5% LE (67% carbohydrates and 13.5% fat); or HCD + 13.5% LE + Exe. Hepatic TG concentration, lipogenic genes, and total FAs were measured on day 8.Results: Oil Red O staining and TG quantification showed hepatic TG accumulation on day 8; the addition of 13.5% LE either with or without Exe suppressed the TG accumulation compared with HCD (P < 0.005). With the use of quantitative reverse transcriptase-polymerase chain reaction analysis, the expression concentrations of lipogenic genes [ATP-citrate lyase, acetyl coenzyme A carboxylase 1, FA synthase (Fasn), and stearoyl coenzyme A desaturase 1 (Scd1)] in the HCD + 13.5% LE group were 26-60% of HCD (P < 0.01) and 11-38% of HCD in the HCD + 13.5% LE + Exe group (P < 0.001), with interactions for Fasn and Scd1 (P < 0.05). With the use of gas chromatography-mass spectrometry analysis, the HCD + 13.5% LE group had lower monounsaturated fatty acids (38.7% of HCD) but higher polyunsaturated fatty acids (164% of HCD) (P < 0.001).Conclusions: In short-term studies designed to resemble the early dynamic stage of the development of hepatic steatosis, the addition of 13.5% LE to a liquid HCD reduced hepatic lipogenesis. Exe exerted an independent protective effect and interacted with LE to further reduce the expression of Scd1.


Asunto(s)
Dieta , Carbohidratos de la Dieta/farmacología , Ácidos Grasos Omega-6/uso terapéutico , Hígado Graso/prevención & control , Lipogénesis , Carrera/fisiología , Triglicéridos/metabolismo , Animales , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/metabolismo , Grasas de la Dieta/administración & dosificación , Grasas de la Dieta/metabolismo , Grasas de la Dieta/farmacología , Grasas de la Dieta/uso terapéutico , Emulsiones , Ácidos Grasos/administración & dosificación , Ácidos Grasos/metabolismo , Ácidos Grasos/farmacología , Ácidos Grasos/uso terapéutico , Ácidos Grasos Monoinsaturados/metabolismo , Ácidos Grasos Omega-6/administración & dosificación , Ácidos Grasos Omega-6/metabolismo , Ácidos Grasos Omega-6/farmacología , Ácidos Grasos Insaturados/metabolismo , Hígado Graso/enzimología , Hígado Graso/metabolismo , Lipogénesis/efectos de los fármacos , Lipogénesis/genética , Lipogénesis/fisiología , Hígado/efectos de los fármacos , Hígado/enzimología , Hígado/metabolismo , Masculino , Ratones Endogámicos C57BL , Soluciones para Nutrición Parenteral , Distribución Aleatoria
5.
J Nutr ; 146(2): 184-90, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26764334

RESUMEN

BACKGROUND: Fibroblast growth factor 21 (FGF21) is a regulator of carbohydrate and lipid metabolism; however, the regulation of Fgf21 gene expression by diet remains incompletely understood. OBJECTIVE: We investigated the effect of a high-carbohydrate (HC) liquid diet, with and without supplementation with a lipid emulsion (LE), and of a high-fat diet (HFD) compared with a low-fat diet (LFD) on the regulation of Fgf21 gene expression in the liver of intact mice. METHODS: C57BL/6 male mice were fed standard feed pellets (SFPs), a purified HC liquid diet (adequate in calories and protein), or an HC liquid diet containing an LE at either 4% or 13.5% of energy for 5 wk (Expt. 1) or 1 wk (Expt. 2). In Expt. 3, mice were fed a purified LFD (∼10% fat) or HFD (∼60% fat) or were fed an HFD and given access to a running wheel for voluntary exercise for 16 wk. RESULTS: Fgf21 mRNA in liver and FGF21 protein in plasma were increased by 3.5- to 7-fold in HC mice compared with SFP mice (P < 0.001), whereas the LE dose-dependently attenuated the induction of Fgf21 expression (P < 0.05). After 16 wk, hepatic Fgf21 mRNA did not differ between LFD and HFD mice but was dramatically reduced in the HFD+exercise group to <20% of the level in the HFD group (P < 0.0001). CONCLUSIONS: In mice, hepatic Fgf21 expression was upregulated by 1 and 5 wk of feeding a lipogenic HC diet but not by 16 wk of feeding an obesogenic HFD, whereas the addition of fat as an LE to the HC formula significantly reduced Fgf21 gene expression and the plasma FGF21 protein concentration. Our results support a strong and reversible response of hepatic Fgf21 expression to shifts in dietary glucose intake.


Asunto(s)
Dieta , Carbohidratos de la Dieta/efectos adversos , Grasas de la Dieta/farmacología , Hígado Graso/metabolismo , Factores de Crecimiento de Fibroblastos/metabolismo , Hígado/efectos de los fármacos , Animales , Dieta con Restricción de Grasas , Dieta Alta en Grasa , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Grasas de la Dieta/efectos adversos , Emulsiones , Hígado Graso/genética , Factores de Crecimiento de Fibroblastos/sangre , Factores de Crecimiento de Fibroblastos/genética , Expresión Génica , Hígado/metabolismo , Masculino , Ratones Endogámicos C57BL , Obesidad/etiología , Condicionamiento Físico Animal/fisiología , ARN Mensajero/metabolismo , Regulación hacia Arriba
6.
J Org Chem ; 81(4): 1571-84, 2016 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-26811990

RESUMEN

Starting with four components, the enantioselective synthesis of prostaglandin E2 methyl ester has been achieved through a highly stereoselective heteroatom-directed conjugate addition reaction and cyclopentanone ring cyclization as the key steps. This asymmetric strategy includes (i) an asymmetric Reformatsky reaction; (ii) conjugate addition of a chiral vinyllithium reagent; (iii) cyclization to form a sulfonylated cyclopentanone in one-pot; followed by (iv) allylation of the side chain. Four carbon-carbon bond-forming processes and three stereogenic centers were established, with the steps from (ii) to (iii) being achieved in a one-pot process.

7.
Biosensors (Basel) ; 14(6)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38920587

RESUMEN

A microfluidic immuno-biosensor detection system consisting of a microfluidic spectrum chip and a micro-spectrometer detection device is presented for the rapid point-of-care (POC) detection and quantification of high-sensitivity C-reactive protein (hs-CRP) in urine. The detection process utilizes a highly specific enzyme-linked immunosorbent assay (ELISA) method, in which capture antibodies and detection antibodies are pre-deposited on the substrate of the microchip and used to form an immune complex with the target antigen. Horseradish peroxidase (HRP) is added as a marker enzyme, followed by a colorimetric reaction using 3,3',5,5'-tetramethylbenzidine (TMB). The absorbance values (a.u.) of the colorimetric reaction compounds are measured using a micro-spectrometer device and used to measure the corresponding hs-CRP concentration according to the pre-established calibration curve. It is shown that the hs-CRP concentration can be determined within 50 min. In addition, the system achieves recovery rates of 93.8-106.2% in blind water samples and 94.5-104.6% in artificial urine. The results showed that the CRP detection results of 41 urine samples from patients with chronic kidney disease (CKD) were highly consistent with the conventional homogeneous particle-enhanced turbidimetric immunoassay (PETIA) method's detection results (R2 = 0.9910). The experimental results showed its applicability in the detection of CRP in both urine and serum. Overall, the results indicate that the current microfluidic ELISA detection system provides an accurate and reliable method for monitoring the hs-CRP concentration in point-of-care applications.


Asunto(s)
Técnicas Biosensibles , Proteína C-Reactiva , Ensayo de Inmunoadsorción Enzimática , Sistemas de Atención de Punto , Proteína C-Reactiva/análisis , Humanos , Dispositivos Laboratorio en un Chip , Microfluídica , Colorimetría
8.
Food Chem ; 407: 135118, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36493490

RESUMEN

A novel assay platform consisting of a finger pump microchip (FPM) and a WiFi-based analytical detection platform is presented for measuring the concentration of methylparaben (MP) in commercial foods. In the presented approach, a low quantity (5 µL) of distilled food sample is dripped onto the FPM and undergoes a modified Fenton reaction at a temperature of 40 °C to form a green-colored complex. The MP concentration is then determined by measuring the color intensity (RGB) of the reaction complex using APP software (self-written) installed on a smartphone. The color intensity Red(R) + Green(G) value of the reaction complex is found to be linearly related (R2 = 0.9944) to the MP concentration for standard samples with different MP concentrations ranging from 100 to 3000 ppm. The proposed method is used to detect the MP concentrations of 12 real-world commercial foods. The MP concentrations measurements are found to deviate by no more than 5.88% from the results obtained using a conventional benchtop method. The presented platform thus offers a feasible and low-cost alternative to existing macroscale techniques for measuring the MP concentration in commercial foods.


Asunto(s)
Colorimetría , Microfluídica , Colorimetría/métodos , Teléfono Inteligente
9.
Micromachines (Basel) ; 14(6)2023 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-37374718

RESUMEN

A microfluidic distillation system is proposed to facilitate the separation and subsequent determination of propionic acid (PA) in foods. The system comprises two main components: (1) a polymethyl methacrylate (PMMA) micro-distillation chip incorporating a micro-evaporator chamber, a sample reservoir, and a serpentine micro-condensation channel; and (2) and a DC-powered distillation module with built-in heating and cooling functions. In the distillation process, homogenized PA sample and de-ionized water are injected into the sample reservoir and micro-evaporator chamber, respectively, and the chip is then mounted on a side of the distillation module. The de-ionized water is heated by the distillation module, and the steam flows from the evaporation chamber to the sample reservoir, where it prompts the formation of PA vapor. The vapor flows through the serpentine microchannel and is condensed under the cooling effects of the distillation module to produce a PA extract solution. A small quantity of the extract is transferred to a macroscale HPLC and photodiode array (PDA) detector system, where the PA concentration is determined using a chromatographic method. The experimental results show that the microfluidic distillation system achieves a distillation (separation) efficiency of around 97% after 15 min. Moreover, in tests performed using 10 commercial baked food samples, the system achieves a limit of detection of 50 mg/L and a limit of quantitation of 96 mg/L, respectively. The practical feasibility of the proposed system is thus confirmed.

10.
Biosensors (Basel) ; 12(7)2022 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-35884299

RESUMEN

A novel assay platform consisting of a microfluidic sliding double-track paper-based chip and a hand-held Raspberry Pi detection system is proposed for determining the albumin-to-creatine ratio (ACR) in human urine. It is a clinically important parameter and can be used for the early detection of related diseases, such as renal insufficiency. In the proposed method, the sliding layer of the microchip is applied and the sample diffuses through two parallel filtration channels to the reaction/detection areas of the microchip to complete the detection reaction, which is a simple method well suited for self-diagnosis of ACR index in human urine. The RGB (red, green, and blue) value intensity signals of the reaction complexes in these two reaction zones are analyzed by a Raspberry Pi computer to derive the ACR value (ALB and CRE concentrations). It is shown that the G + B value intensity signal is linearly related to the ALB and CRE concentrations with the correlation coefficients of R2 = 0.9919 and R2 = 0.9923, respectively. It is additionally shown that the ALB and CRE concentration results determined using the proposed method for 23 urine samples were collected from real suffering chronic kidney disease (CKD) patients are in fine agreement with those acquired operating a traditional high-reliability macroscale method. Overall, for point-of-care (POC) CKD diagnosis and monitoring in clinical applications, the results prove that the proposed method offers a convenient, real time, reliable, and low-spending solution for POC CKD diagnosis.


Asunto(s)
Creatina , Insuficiencia Renal Crónica , Albúminas/análisis , Creatinina/orina , Humanos , Microfluídica , Sistemas de Atención de Punto , Insuficiencia Renal Crónica/diagnóstico , Reproducibilidad de los Resultados
11.
Biomed Pharmacother ; 151: 113084, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35567985

RESUMEN

We report the design, synthesis and evaluation of a class of phosphatidylserine-targeting zinc (II) dipicolylamine drug conjugates and show that conjugate 16b elicits immune cell infiltration and remodels the "cold" hepatic tumor microenvironment to the inflamed "hot" tumor. Structure-property relationship study via linker modifications and subsequent pharmacokinetics profiling were carried out to improve the solubility and stability of the conjugates in vivo. In a spontaneous hepatocellular carcinoma mouse model, we showed that conjugate 16b exhibited better antitumor efficacy than sorafenib. In particular, significant increase of CD8+ T cell infiltration and granzyme B level was observed, providing insights in sensitizing tumors from intrinsic immune suppressive microenvironment. Evaluation of tumor inflammation-related mRNA expression profile revealed that conjugate 16b, through inductions of key gene expressions including STAT1, CXCL9, CCL5, and PD-L1, rejuvenated tumor microenvironment with enhancement in T cell-, macrophage-, NK cell-, chemokines and cytokines'- functions. Our study establishes that an apoptosis-targeting theranostic enables enrichment of multifaceted immune cells into the tumor mass, which provides potential therapeutic strategies in the combination with immune checkpoint blockade treatment.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Inhibidores de Puntos de Control Inmunológico , Neoplasias Hepáticas/tratamiento farmacológico , Ratones , Fosfatidilserinas , Microambiente Tumoral
12.
Pharmaceutics ; 14(7)2022 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-35890212

RESUMEN

Ligand-targeting drug conjugates are a class of clinically validated biopharmaceutical drugs constructed by conjugating cytotoxic drugs with specific disease antigen targeting ligands through appropriate linkers. The integrated linker-drug motif embedded within such a system can prevent the premature release during systemic circulation, thereby allowing the targeting ligand to engage with the disease antigen and selective accumulation. We have designed and synthesized new thioester-linked maytansinoid conjugates. By performing in vitro cytotoxicity, targeting ligand binding assay, and in vivo pharmacokinetic studies, we investigated the utility of this new linker-drug moiety in the small molecule drug conjugate (SMDC) system. In particular, we conjugated the thioester-linked maytansinoids to the phosphatidylserine-targeting small molecule zinc dipicolylamine and showed that Zn8_DM1 induced tumor regression in the HCC1806 triple-negative breast cancer xenograft model. Moreover, in a spontaneous sorafenib-resistant liver cancer model, Zn8_DM1 exhibited potent antitumor growth efficacy. From quantitative mRNA analysis of Zn8_DM1 treated-tumor tissues, we observed the elevation of gene expressions associated with a "hot inflamed tumor" state. With the identification and validation of a plethora of cancer-associated antigens in the "omics" era, this work provided the insight that antibody- or small molecule-based targeting ligands can be conjugated similarly to generate new ligand-targeting drug conjugates.

13.
Toxins (Basel) ; 13(6)2021 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-34199493

RESUMEN

External urethral sphincter (EUS) dysfunction is a common, bothersome female voiding dysfunction. This study aims to analyze the characteristics of different types of female EUS dysfunction, as well as to determine the outcome predictors of sphincteric botulinum toxin A (BoNT-A) injection. Women receiving sphincteric BoNT-A injections for refractory EUS dysfunction were retrospectively reviewed. A comparison of the baseline clinical, urodynamic parameters and the treatment responses were made for patients with different EUS dysfunctions. A total of 106 females were included. Significantly increased detrusor overactivity, detrusor contracting pressure and the bladder outlet obstruction index with decreased urge sensation were noted in patients diagnosed with dysfunctional voiding or detrusor sphincter dyssynergia comparing to those diagnosed with poor relaxation of the external urethral sphincter. The average subjective improvement rate was 67% for the injection. The therapeutic effect was not affected by the type of EUS dysfunction. The multivariate analysis revealed that bladder neck narrowing and catheterization history were predictive of negative outcomes. There is a distinct urodynamic presentation for each type of female EUS dysfunction. Sphincteric BoNT-A injection provides a good therapeutic outcome for refractory EUS dysfunction. A narrowing bladder neck and a history of catheterization suggest poor therapeutic outcomes.


Asunto(s)
Toxinas Botulínicas Tipo A/uso terapéutico , Fármacos Neuromusculares/uso terapéutico , Enfermedades Uretrales/tratamiento farmacológico , Trastornos Urinarios/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inyecciones , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Uretra/efectos de los fármacos , Uretra/fisiopatología , Enfermedades Uretrales/fisiopatología , Vejiga Urinaria/efectos de los fármacos , Vejiga Urinaria/fisiopatología , Trastornos Urinarios/fisiopatología
14.
Front Oncol ; 11: 757359, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34900706

RESUMEN

PURPOSE: Pathology reviews for upper urinary tract cancer (UTUC) remained scarce in the literature. Here, we reported the interobserver variation among the review and local pathologies of featured histologic characteristics for UTUC. METHODS: Patients who underwent definitive surgical treatments for UTUC were retrospectively reviewed for eligibility of pathology review. In the Taiwan UTUC Collaboration cohort, 212 cases were reviewed, of which 154 cases were eligible for pathology review. Agreement between original pathology and review pathology was measured by the total percentage of agreement and by simple kappa statistics. The prognostic impact was analyzed by the Cox regression model with the estimation of hazard ratios (HR) and 95% confidence intervals. RESULTS: There were 80 women and 74 men enrolled in this study, and the median age at treatment was 71.7 years. The agreement is moderate agreement for surgical margin status (87.7%; κ = 0.61), tumor grade (82.5%; κ = 0.43), tumor invasiveness (76.6%; κ = 0.45), lymphovascular invasion (70.8%; κ = 0.42) and T stage (67.5%; κ = 0.52). The interobserver agreements for perineural invasion and variant histology identification were slight. Kaplan-Meier analysis for disease-free survival revealed comparable results in local and review pathology for localized (Tis, Ta, T1-2) or advanced T stage (T3-4). CONCLUSIONS: Pathology review of UTUC had minimal impact on clinical practice based on current available disease treatment guidelines. However, significant interobserver variations were observed in featured adverse histopathological characters.

15.
Front Chem ; 9: 822587, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35242746

RESUMEN

An efficient Ugi multicomponent reaction with strain promoted azide-alkyne cycloaddition protocol has been utilized in concert or independently to prepare a small family of bioactive zinc(II) dipicolylamine (ZnDPA)-based SN-38 conjugates. With sequential click chemistry coupling between the cytotoxic payload and phosphatidylserine-targeting ZnDPA ligand derived from structurally diverse carboxylic acids, aldehyde or ketones, and isocyanides, we demonstrated that this convergent synthetic strategy could furnish conjugates harnessing diversified linkers that exhibited different pharmacokinetic profiles in systemic circulation in vivo. Among the eight new conjugates, comparative studies on in vitro cytotoxicities, plasma stabilities, in vivo pharmacokinetic properties, and maximum tolerated doses were then carried out to identify a potent ZnDPA-based SN-38 conjugate that resulted in pancreatic cancer growth regression with an 80% reduction of cytotoxic payload used when compared to that of the marketed irinotecan. Our work provided the roadmap to construct a variety of theranostic agents in a similar manner for cancer treatment.

16.
Redox Biol ; 46: 102126, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34509914

RESUMEN

Nitro-fatty acids are a class of endogenous electrophilic lipid mediators with anti-inflammatory and cytoprotective effects in a wide range of inflammatory and fibrotic disease models. While these beneficial biological effects of nitro-fatty acids are mainly attributed to their ability to form covalent adducts with proteins, only a small number of proteins are known to be nitro-alkylated and the scope of protein nitro-alkylation remains undetermined. Here we describe the synthesis and application of a clickable nitro-fatty acid probe for the detection and first global identification of mammalian proteins that are susceptible to nitro-alkylation. 184 high confidence nitro-alkylated proteins were identified in THP1 macrophages, majority of which are novel targets of nitro-fatty acids, including extended synaptotagmin 2 (ESYT2), signal transducer and activator of transcription 3 (STAT3), toll-like receptor 2 (TLR2), retinoid X receptor alpha (RXRα) and glucocorticoid receptor (NR3C1). In particular, we showed that 9-nitro-oleate covalently modified and inhibited dexamethasone binding to NR3C1. Bioinformatic analyses revealed that nitro-alkylated proteins are highly enriched in endoplasmic reticulum and transmembrane proteins, and are overrepresented in lipid metabolism and transport pathways. This study significantly expands the scope of protein substrates targeted by nitro-fatty acids in living cells and provides a useful resource towards understanding the pleiotropic biological roles of nitro-fatty acids as signaling molecules or as multi-target therapeutic agents.


Asunto(s)
Ácidos Grasos , Nitrocompuestos , Alquilación , Animales , Unión Proteica , Transducción de Señal
17.
Br J Nutr ; 104(5): 686-92, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20388249

RESUMEN

Arginine (Arg) is known to possess numerous useful physiological properties and have immunomodulatory effects. In vitro studies reported that Arg inhibits advanced glycation endproduct (AGE) formation; however, the effects of Arg on the receptor of AGE (RAGE) expression in inflammatory conditions are not clear. The present study investigated the effects of dietary Arg supplementation on inflammatory mediator production and RAGE expression in type 2 diabetic rats. There were one normal control (NC) group and two diabetic groups in the present study. Rats in the NC group were fed with a regular chow diet. One diabetic group (DM) was fed a common semi-purified diet while the other diabetic group received a diet in which part of the casein was replaced by Arg (DM-Arg) for 8 weeks. Diabetes was induced by an intraperitoneal injection of nicotinamide followed by streptozotocin. Rats with blood glucose levels exceeding 1800 mg/l were considered diabetic. Blood samples and the liver and lungs of the animals were collected at the end of the study for further analysis. Results showed that plasma glucose and fructosamine contents were significantly higher in the diabetic groups than those in the NC group. The DM group had higher fructosamine and C-reactive protein than the DM-Arg group. Immunohistochemical staining showed that the expressions of RAGE in liver and lung tissues were significantly lower in the DM-Arg group than in the DM group. These results suggest that supplemental dietary Arg can decrease AGE-RAGE interactions and consequently reduce tissue damage in rats with type 2 diabetes.


Asunto(s)
Arginina/uso terapéutico , Glucemia/metabolismo , Proteína C-Reactiva/metabolismo , Diabetes Mellitus Experimental/dietoterapia , Suplementos Dietéticos , Fructosamina/sangre , Receptores Inmunológicos/metabolismo , Animales , Arginina/farmacología , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Mediadores de Inflamación/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Masculino , Ratas , Ratas Wistar , Receptor para Productos Finales de Glicación Avanzada
18.
Toxins (Basel) ; 11(12)2019 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-31847090

RESUMEN

Neurogenic and non-neurogenic urethral sphincter dysfunction are common causes of voiding dysfunction. Injections of botulinum toxin A (BoNT-A) into the urethral sphincter have been used to treat urethral sphincter dysfunction (USD) refractory to conventional treatment. Since its first use for patients with detrusor sphincter dyssynergia in 1988, BoNT-A has been applied to various causes of USD, including dysfunctional voiding, Fowler's syndrome, and poor relaxation of the external urethral sphincter. BoNT-A is believed to decrease urethral resistance via paralysis of the striated sphincter muscle through inhibition of acetylcholine release in the neuromuscular junction. Recovery of detrusor function in patients with detrusor underactivity combined with a hyperactive sphincter also suggested the potential neuromodulation effect of sphincteric BoNT-A injection. A large proportion of patients with different causes of USD report significant improvement in voiding after sphincteric BoNT-A injections. However, patient satisfaction might not increase with an improvement in the symptoms because of concomitant side effects including exacerbated incontinence, urinary urgency, and over-expectation. Nonetheless, in terms of efficacy and safety, BoNT-A is still a reasonable option for refractory voiding function. To date, studies focusing on urethral sphincter BoNT-A injections have been limited to the heterogeneous etiologies of USD. Further well-designed studies are thus needed.


Asunto(s)
Toxinas Botulínicas Tipo A/uso terapéutico , Trastornos Urinarios/tratamiento farmacológico , Animales , Humanos , Inyecciones , Uretra/fisiopatología , Trastornos Urinarios/fisiopatología
19.
J Med Chem ; 62(13): 6047-6062, 2019 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-31181158

RESUMEN

We report that compound 13, a novel phosphatidylserine-targeting zinc(II) dipicolylamine drug conjugate, readily triggers a positive feedback therapeutic loop through the in situ generation of phosphatidylserine in the tumor microenvironment. Linker modifications, pharmacokinetics profiling, in vivo antitumor studies, and micro-Western array of treated-tumor tissues were employed to show that this class of conjugates induced regeneration of apoptotic signals, which facilitated subsequent recruitment of the circulating conjugates through the zinc(II) dipicolylamine-phosphatidylserine association and resulted in compounding antitumor efficacy. Compared to the marketed compound 17, compound 13 not only induced regressions in colorectal and pancreatic tumor models, it also exhibited at least 5-fold enhancement in antitumor efficacy with only 40% of the drug employed during treatment, culminating in a >12.5-fold increase in therapeutic potential. Our study discloses a chemically distinct apoptosis-targeting theranostic, with built-in complementary functional moieties between the targeting module and the drug mechanism to expand the arsenal of antitumor therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Complejos de Coordinación/uso terapéutico , Indolizinas/uso terapéutico , Neoplasias/tratamiento farmacológico , Fosfatidilserinas/metabolismo , Picolinas/uso terapéutico , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Diseño de Fármacos , Humanos , Indolizinas/síntesis química , Indolizinas/química , Masculino , Ratones Endogámicos ICR , Ratones Desnudos , Estructura Molecular , Picolinas/síntesis química , Picolinas/química , Relación Estructura-Actividad , Inhibidores de Topoisomerasa I/síntesis química , Inhibidores de Topoisomerasa I/química , Inhibidores de Topoisomerasa I/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto , Zinc/química
20.
Metabolism ; 63(10): 1352-62, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25060692

RESUMEN

OBJECTIVE: Patatin-like phospholipase domain containing 3 (PNPLA3, adiponutrin) has been identified as a modifier of lipid metabolism. To better understand the physiological role of PNPLA3/adiponutrin, we have investigated its regulation in intact mice and human hepatocytes under various nutritional/metabolic conditions. MATERIAL/METHODS: PNPLA3 gene expression was determined by real-time PCR in liver of C57BL/6 mice after dietary treatments and in HepG2 cells exposed to various nutritional/metabolic stimuli. Intracellular lipid content was determined in HepG2 cells after siRNA-mediated knockdown of PNPLA3. RESULTS: In vivo, mice fed a high-carbohydrate (HC) liquid diet had elevated hepatic lipid content, and PNPLA3 mRNA and protein expression, compared to chow-fed mice. Elevated expression was completely abrogated by addition of unsaturated lipid emulsion to the HC diet. By contrast, in mice with high-fat diet-induced steatosis, Pnpla3 expression did not differ compared to low-fat fed mice. In HepG2 cells, Pnpla3 expression was reversibly suppressed by glucose depletion and increased by glucose refeeding, but unchanged by addition of insulin and glucagon. Several unsaturated fatty acids each significantly decreased Pnpla3 mRNA, similar to lipid emulsion in vivo. However, Pnpla3 knockdown in HepG2 cells did not alter total lipid content in high glucose- or oleic acid-treated cells. CONCLUSIONS: Our results provide evidence that PNPLA3 expression is an early signal/signature of carbohydrate-induced lipogenesis, but its expression is not associated with steatosis per se. Under lipogenic conditions due to high-carbohydrate feeding, certain unsaturated fatty acids can effectively suppress both lipogenesis and PNPLA3 expression, both in vivo and in a hepatocyte cell line.


Asunto(s)
Carbohidratos de la Dieta/metabolismo , Hígado Graso/genética , Expresión Génica/genética , Metabolismo de los Lípidos/genética , Lípidos/genética , Proteínas de la Membrana/genética , Animales , Línea Celular Tumoral , Dieta Alta en Grasa/métodos , Hígado Graso/metabolismo , Glucagón/metabolismo , Glucosa/metabolismo , Células Hep G2 , Hepatocitos/metabolismo , Humanos , Insulina/metabolismo , Lipogénesis/genética , Hígado/metabolismo , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico
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