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2.
Clin Transl Sci ; 16(6): 987-1001, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36967488

RESUMEN

The objective of the current study was to identify potential drug-drug interactions (DDIs) with the drug candidate fb-PMT, a novel anticancer thyrointegrin αvß3 antagonist. This was accomplished by using several in vitro assays to study interactions of fb-PMT with both cytochrome P450 (CYP) enzymes and drug transporters, two common mechanisms leading to adverse drug effects. In vitro experiments showed that fb-PMT exhibited weak reversible inhibition of CYP2C19 and CYP3A4. In addition, fb-PMT did not show time-dependent inhibition with any of the seven CYP isoforms tested, including 1A2, 2B6, 2C8, 2C9, 2C19, 2D6, and 3A4. Human liver microsomal incubations demonstrated that fb-PMT is stable. Potential transporter-mediated DDIs with fb-PMT were assessed with two ATP binding cassette (ABC) family transporters (P-glycoprotein and breast cancer resistance protein) using Caco2 cells and seven solute carrier family (SLC) transporters (organic cation transporter OCT2, organic anion transporters OAT1 and OAT3, organic anion transporter peptides OATP1B1 and OATP1B3, and the multidrug and toxic extrusion proteins MATE1 and MATE2-K using transfected HEK293 cells). Fb-PMT was not a substrate for any of the nine transporters tested in this study, nor did it inhibit the activity of seven of the transporters tested. However, fb-PMT inhibited the uptake of rosuvastatin by both OATP1B1 and OATP1B3 with half-maximal inhibitory concentrations greater than 3 and less than 10 µM. In summary, data suggest that the systemic administration of fb-PMT is unlikely to lead to DDIs through CYP enzymes or ABC and SLC transporters in humans.


Asunto(s)
Transportadores de Anión Orgánico Sodio-Independiente , Transportadores de Anión Orgánico , Humanos , Transportadores de Anión Orgánico Sodio-Independiente/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Células CACO-2 , Células HEK293 , Proteínas de Neoplasias/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Interacciones Farmacológicas , Transportadoras de Casetes de Unión a ATP/metabolismo , Transportadores de Anión Orgánico/metabolismo
3.
Front Pharmacol ; 13: 902141, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36518666

RESUMEN

We have recently reported on the development of fb-PMT (NP751), a conjugate of the thyroid hormone metabolite tetraiodothyroacetic acid (tetrac) and monodisperse polyethylene glycol 36. It exhibited high affinity for thyrointegrin αvß3 receptor and potent anti-angiogenic and anticancer activity in vivo. The objective of the current study is to determine the pharmacokinetics (PK) of fb-PMT in experimental animals, such as mice, rats, and monkeys. NP751 was quantified using a propylene diamine-modified tetraiodothyroacetic acid (DAT) as an internal standard. The limit of quantification (LOQ) for fb-PMT was 1.5 ng/µL and the recovery efficiency was 93.9% with the developed method. The peak plasma concentration (Cmax) and the area under the curve (AUC) results at different doses in mice, rats and monkeys suggest that pharmacokinetics of NP751 is dose-dependent within the dose ranges administered. Results indicate that NP751 has comparable PK parameters that provides enough exposure as a molecularly tumor targeted molecule in multiple species and is a promising anticancer therapeutic.

5.
J Pharm Pharmacol Res ; 6(2): 80-92, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35903625

RESUMEN

Catechin polyphenols are the major bioactive ingredients in green tea with various human health benefits. Extraction of catechins from green tea (GTE) leaves at optimized standard conditions is still a challenging approach. An optimized, rapid, and economic extraction method is industrially needed. We hypothesized that certain extraction techniques in the presence of natural polymers and antioxidants might improve GTE catechin extraction yield and its biological activity. The effect of microwave (30-60 seconds irradiation in a typical kitchen microwave) assisted extraction (MAE) and ultrasonic assisted extraction (UAE) techniques were evaluated separately and in combination. To study the effect of the extraction solvent, nine edible green solvent combinations were investigated namely water, ascorbic acid, chitosan/ascorbic acid, carboxymethylcellulose /ascorbic acid, methylcellulose /ascorbic acid, chitosan/methylcellulose/ascorbic acid, methylcellulose, chitosan/acetic acid, and ethanol. The amounts of extracted catechins from green tea leaves were quantified with HPLC-UV. Data showed that the use of MAE & UAE technique was the optimal in producing a higher extraction yield of catechins. Chitosan/ascorbic acid was the optimized solvent with high extraction efficiencies of catechins. Studies in high fat diet fed animals demonstrated significant reduction of total cholesterol and LDL-C by GTE after 3 weeks of oral daily administration. In conclusion, efficient extraction, and stabilization of catechins from green tea leaves demonstrated a significant lowering of high fat diet-mediated elevation in blood cholesterol and LDL-C levels.

6.
J Cancer ; 13(8): 2594-2606, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35711848

RESUMEN

Background: In neuroendocrine tumors, the norepinephrine transporter (NET) is very active and has been exploited for diagnostic imaging purposes and/or therapy with localized radiotherapy. Integrin αvß3 is generously expressed by and/or activated on cancer cells, but not by nonmalignant cells. Purpose: In the present investigation, the anticancer efficacy of the dual targeting of norepinephrine transporter (NET), benzylguanidine (BG), and thyrointegrin αvß3 receptors antagonist triazole tetraiodothyroacetic acid (TAT) conjugated via the non-cleavable linker polyethylene glycol (P, PEG400) in the treatment of human neuroblastoma was evaluated. Experimental approach: The synthesized dual targeting compound, a novel new chemical entity named BG-P400-TAT, has purity > 98% and was formulated and tested in neuroblastoma models using neuroblastoma cell lines (SK-N-FI, SMS-KCN and SMS-KANR) implanted in SCID and NSG mice models. Key Results: BG-P400-TAT demonstrated significant (**P<0.01, ***P< 0.001) suppression of neuroblastoma tumor progression, growth, and viability in both mice models implanted with the neuroblastoma. The pharmacokinetic and biodistribution profile of BG-P400-TAT showed a significant increase in BG-P400-TAT levels in plasma and xenografts of NSG compared to SCID mice. Further our RNAseq genome-wide expression profiling experiments in neuroblastoma cell line SKNAS results showed that BG-P400-TAT treatment altered the signal transduction pathways, intracellular multiprotein complexes and Independent GSEA. Conclusion & Implications: BG-P400-TAT represents a potential lead candidate for the treatment of neuroblastoma and other neuroendocrine tumors.

8.
Nanomedicine ; 44: 102580, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35768037

RESUMEN

Ultraviolet Beam (UVB) radiation is the main cause of skin cancer worldwide. Besides biocompatibility, the instability and limited skin permeability are the most challenging features of many effective photochemopreventive agents. (-)-Epigallocatechin-3-gallate (EGCG) is a natural polyphenolic compound extracted from Camellia sinensis that has been demonstrated to have antioxidant, anti-inflammatory, and anti-cancer properties. We evaluated the efficacy of three innovative EGCG nanoformulations in chemoprevention of UVB-induced DNA damage in keratinocytes. Results indicated that the EGCG nanoformulations reduced UVB-induced oxidative stress elevation and DNA damage. The nanoformulations also reduced the UVB-induced formation of pyrimidine and pyrimidone photoproducts in 2D human immortalized HaCaT keratinocytes and SKH-1 hairless mice through antioxidant effects and possibly through absorption of UVB radiation. In addition, EGCG nanoformulations inhibited UVB-induced chemokine/cytokine activation and promoted EGCG skin permeability and stability. Taken together, the results suggest the use of EGCG nanoformulations as potential natural chemopreventive agents during exposure to UVB radiation.


Asunto(s)
Catequina , Animales , Antioxidantes/farmacología , Catequina/análogos & derivados , Catequina/farmacología , Daño del ADN , Humanos , Queratinocitos , Ratones , Ratones Pelados , Piel , Rayos Ultravioleta
9.
Sci Rep ; 12(1): 5114, 2022 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-35332220

RESUMEN

Neonicotinoid pesticides are a class of insecticides that reportedly have harmful effects on bees and dragonflies, causing a reduction in their numbers. Neonicotinoids act as neuroreceptor modulators, and some studies have reported their association with neurodevelopmental disorders. However, the precise effect of neonicotinoids on the central nervous system has not yet been identified. Herein, we conducted in vivo Ca2+ imaging using a two-photon microscope to detect the abnormal activity of neuronal circuits in the brain after neonicotinoid application. The oral administration of acetamiprid (ACE) (20 mg/kg body weight (BW) in mature mice with a quantity less than the no-observed-adverse-effect level (NOAEL) and a tenth or half of the median lethal dose (LD50) of nicotine (0.33 or 1.65 mg/kg BW, respectively), as a typical nicotinic acetylcholine receptor (nAChR) agonist, increased anxiety-like behavior associated with altered activities of the neuronal population in the somatosensory cortex. Furthermore, we detected ACE and its metabolites in the brain, 1 h after ACE administration. The results suggested that in vivo Ca2+ imaging using a two-photon microscope enabled the highly sensitive detection of neurotoxicant-mediated brain disturbance of nerves.


Asunto(s)
Insecticidas , Odonata , Animales , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Insecticidas/metabolismo , Insecticidas/toxicidad , Ratones , Microscopía , Neonicotinoides/metabolismo , Neonicotinoides/toxicidad , Agonistas Nicotínicos
10.
Environ Int ; 162: 107169, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35289289

RESUMEN

Neonicotinoid insecticides (NNIs) are a popular class of insecticides used in various pest management regimens worldwide. Biomonitoring studies continuously report high exposure rates of NNIs in various human populations across the globe. Yet, there is no validated countermeasure for combating the recent exponential rise in NNI exposure rates observed in human populations. The current study assessed the impacts of organic dietary interventions on NNI exposure rates in a Japanese population. A total of 103 volunteers were recruited into the study. Subjects were either served with Organic diets for 5 and 30 days or conventional diets. A total of 919 repeated urine samples were collected from the participants and then subjected to LC-MS/MS analysis to determine urinary concentrations of 7 NNIs parent compounds and an NNI metabolite. Eight NNIs were detected; with a decreasing detection frequency (%Dfs) pattern; desmethyl-acetamiprid (dm-ACE) (64.96%) > dinotefuran (52.12%), imidacloprid (39.61%) > clothianidin (33.95%) > thiamethoxam (28.51%) > acetamiprid (12.62%) > nitenpyram (5.33%) > thiacloprid (2.83%). Dinotefuran, dm-ACE, and clothianidin recorded the highest concentrations in the subjects. The %Df of NNIs in the 5-days or 30-days organic diet group were lower than those of the conventional diet consumers. The organic diet group showed lower rates of multiple NNI exposures than those of the conventional diet consumers. The mean and median cumulative levels of NNIs (median IMIeq) were significantly lower in the organic diet group than the conventional diet group (p < 0.0001). The estimated daily intakes (EDIs) of NNIs were higher in adults than children, but less than 1% of NNI cRfDs, except for clothianidin, which exhibited a %cRfD of 1.32 in children. Compared to the conventional diet group, the 5- and 30-day organic dietary intervention showed drastic reductions in NNI EDIs. Findings from the present study give credence to organic dietary interventions as potential ameliorative strategies for NNI exposure rates in human populations.


Asunto(s)
Insecticidas , Adulto , Niño , Cromatografía Liquida , Humanos , Insecticidas/análisis , Japón , Neonicotinoides , Nitrocompuestos , Espectrometría de Masas en Tándem
11.
Nanomedicine ; 40: 102480, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34748962

RESUMEN

Proprotein convertase subtilisin/kexin type 9 is a protease enzyme secreted by liver that downregulates hepatic low-density lipoprotein receptor (LDLR) by binding and chaperoning LDLR to lysosomes for degradation, causing hypercholesteremia. The development of anti-PCSK9 therapeutics attracted considerable attention for the management of cardiovascular disease risk. However, only subcutaneous injectable PCSK9 monoclonal antibodies have been FDA approved. Oral administration of small-molecule PCSK9 inhibitors has the potential to become a practical therapeutic option if achievable. In the present work, we used nanotechnological approaches to develop the first small oral molecule nano-hepatic targeted anti-PCSK9. Using high-throughput optimization and a series of evaluations, a stable water-dispersible 150-200 nm nano-encapsulated drug (named P-4) conjugated with hepatic targeting moiety was synthesized and characterized (named P-21). Pharmacodynamic (PD), pharmacokinetic (PK) and bioavailability studies were conducted using a high fat diet nutritionally induced hypercholesterolemia mouse model to evaluate the efficacy of P-21 as an anti-PCSK9 LDL-cholesterol lowering hepatic targeted nanodrug. The PD results demonstrate that P-21 in a dose-dependent manner is highly effective in lowering LDL-C by 50-90%. PK results show the maximum plasma concentration (Cmax) of P-4 was observed after 30 min of administration with 31% oral bioavailability and had a sustained longer half-life up to 24 h. In vivo safety studies in rats showed no apparent adverse effects, normal chemical biomarkers and normal histopathological findings in all P-21 treated groups at different escalating doses. Compared to the FDA-approved monoclonal antibodies, P-21 offers a more efficient, and practical treatment protocol for targeting uncontrolled hypercholesterolemia in reducing the risk of cardiovascular diseases. The present study introduced a nano-targeted drug delivery approaches for PCSK9/LDLR antagonist.


Asunto(s)
Hipercolesterolemia , Proproteína Convertasa 9 , Animales , LDL-Colesterol/metabolismo , LDL-Colesterol/uso terapéutico , Hipercolesterolemia/tratamiento farmacológico , Hipercolesterolemia/metabolismo , Hígado/metabolismo , Ratones , Proproteína Convertasa 9/metabolismo , Proproteína Convertasa 9/uso terapéutico , Ratas , Receptores de LDL/metabolismo
12.
Biomedicines ; 9(11)2021 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-34829942

RESUMEN

Ischemic heart disease is the main cause of death globally. Cardioprotection is the process whereby mechanisms that reduce myocardial damage, and activate protective factors, contribute to the preservation of the heart. Targeting these processes could be a new strategy in the treatment of post-ischemic heart failure (HF). Triiodothyronine (T3) and thyroxine (T4), which have multiple effects on the heart, prevent myocardial damage. This study describes the formulation, and characterization, of chemically modified polymeric nanoparticles incorporating T3, to target the thyroid hormone receptors. Modified T3 was conjugated to polylactide-co-glycolide (PLGA) to facilitate T3 delivery and restrict its nuclear translocation. Modified T3 and PLGA-T3 was characterized with 1H-NMR. The protective role of synthesized phosphocreatine (PCr) encapsulated PLGA-T3 nanoparticles (PLGA-T3/PCr NPs) and PLGA-T3 nanoparticles (PLGA-T3 NPs) in hypoxia-mediated cardiac cell insults was investigated. The results showed that PLGA-T3/PCr NPs represent a potentially new therapeutic agent for the control of tissue damage in cardiac ischemia and resuscitation.

13.
Sci Rep ; 11(1): 22484, 2021 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-34795341

RESUMEN

Neonicotinoids are systemic insecticides used since the 1990's , that possess renal tubular toxicity. We conducted a field-based descriptive study in the North Central Dry-zone of Sri Lanka, where chronic kidney disease (CKD) of unknown etiology has been increasing since the 1990's. To elucidate the relationship between renal tubular dysfunctions and urinary neonicotinoids concentrations, we collected spot urine samples from15 CKD patients, 15 family members, and 62 neighbors in 2015, analyzed two renal tubular biomarkers, Cystatin-C and L-FABP, quantified seven neonicotinoids and a metabolite N-desmethyl-acetamiprid by LC-MS/MS; and we investigated their symptoms using a questionnaire. Cystatin-C and L-FABP had a positive correlation (p < 0.001). N-Desmethyl-acetamiprid was detected in 92.4% of the urine samples, followed by dinotefuran (17.4%), thiamethoxam (17.4%), clothianidin (9.8%), thiacloprid and imidacloprid. Dinotefuran and thiacloprid have never been registered in Sri Lanka. In High Cystatin-C group (> 70 µg/gCre, n = 7), higher urinary concentration of dinotefuran (p = 0.009), and in Zero Cystatin-C group (< LOQ, n = 7), higher N-desmethyl-acetamiprid (p = 0.013), dinotefuran (p = 0.049), and thiacloprid (p = 0.035), and more complaints of chest pains, stomachache, skin eruption and diarrhea (p < 0.05) were found than in Normal Cystatin-C group (n = 78). Urinary neonicotinoids may be one of the potential risk factors for renal tubular dysfunction in this area.


Asunto(s)
Insecticidas/orina , Túbulos Renales/efectos de los fármacos , Neonicotinoides/orina , Enfermedades del Sistema Nervioso/orina , Insuficiencia Renal Crónica/orina , Adulto , Biomarcadores/orina , Cromatografía Liquida , Cistatina C/orina , Agricultores , Proteínas de Unión a Ácidos Grasos/orina , Femenino , Geografía , Guanidinas/orina , Humanos , Masculino , Persona de Mediana Edad , Nitrocompuestos/orina , Piridinas/orina , Control de Calidad , Sri Lanka/epidemiología , Encuestas y Cuestionarios , Espectrometría de Masas en Tándem , Tiametoxam/orina , Tiazinas/orina , Tiazoles/orina
14.
Nanomedicine (Lond) ; 16(26): 2331-2342, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34651508

RESUMEN

Aim: We previously synthesized a polyethylene glycol-based norepinephrine transporter-targeted agent, BG-P-TAT, which has a benzylguanidine and a triazolyl-tetrac group. This targeted conjugate showed suppression of neuroblastoma tumor progression. In this study we aimed to synthesize nanoparticles to encapsulate the chemotherapeutic agent paclitaxel for targeting neuroblastoma tumors by using benzylguanidine so that it can compete with norepinephrine for uptake by neuroendocrine cells. Methods: Biocompatible poly(lactide-co-glycolic acid)-polyethylene glycol was chosen to prepare targeted nanoparticles for safe delivery of the chemotherapy agent paclitaxel. Result: Paclitaxel concentration was 60% higher in neuroblastoma tumors of mice treated with paclitaxel encapsulated in targeted nanoparticles than with non-targeted nanoparticles. Conclusion: These findings support the targeted delivery of paclitaxel as a chemotherapeutic agent for neuroblastoma.


Asunto(s)
Nanopartículas , Neuroblastoma , Paclitaxel , Animales , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos , Guanidinas , Ratones , Neuroblastoma/tratamiento farmacológico , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática , Polietilenglicoles
15.
Toxicol Rep ; 8: 1657-1664, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34584850

RESUMEN

The current study sought to assess the residual levels of neonicotinoid insecticides (NEO) in organic and conventional green tea leaves produced in Japan. A total of 103 tea leaves (thus, 42 organic and 61 conventional), were sampled from grocery stores in Japan. Concentrations of NEOs in the tea leaves were quantified using LC-MS/MS; and the data was used to estimate maximum daily intakes of NEOs within the Japanese population. Seven native NEO compounds and one NEO metabolite were detected in both organic and conventional tea leaves. Detection frequencies (%Dfs) of NEOs in the tea samples (n = 103) were found in the decreasing order; thiacloprid (84.47 %) > dinotefuran (74.76 %) > imidacloprid (69.90 %) ≈ clothianidin (69.90 %) > dm-acetamiprid (63.11 %) > thiamethoxam (58.25 %) > acetamiprid (4.85 %) > nitenpyram (1.94 %). About 94.20 % of the tea leaves contained two or more NEO compounds simultaneously. The %Dfs of NEOs were relatively lower in organic tea leaves, compared to the conventional tea leaves. Various percentile concentrations of NEOs were far lower in organic tea leaves, compared to the conventional tea leaves. The maximum daily intakes of NEOs through consumption of tea (MDIgt) were also lower for organic tea leaves, compared to the conventional tea samples.

16.
J Chromatogr A ; 1652: 462350, 2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-34198103

RESUMEN

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


Asunto(s)
Cromatografía Liquida , Insecticidas/farmacocinética , Neonicotinoides/farmacocinética , Nitrocompuestos/farmacocinética , Espectrometría de Masas en Tándem , Tejido Adiposo Blanco/metabolismo , Animales , Encéfalo/metabolismo , Insecticidas/administración & dosificación , Insecticidas/análisis , Insecticidas/sangre , Riñón/metabolismo , Hígado/metabolismo , Masculino , Ratones Endogámicos C57BL , Neonicotinoides/administración & dosificación , Neonicotinoides/análisis , Neonicotinoides/sangre , Nitrocompuestos/administración & dosificación , Nitrocompuestos/análisis , Nitrocompuestos/sangre , Testículo/metabolismo , Distribución Tisular
17.
Bioorg Med Chem ; 42: 116250, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34118788

RESUMEN

Receptor-mediated cancer therapy has received much attention in the last few decades. Neuroblastoma and other cancers of the sympathetic nervous system highly express norepinephrine transporter (NET) and cell plasma membrane integrin αvß3. Dual targeting of the NET and integrin αvß3 receptors using a Drug-Drug Conjugate (DDC) might provide effective treatment strategy in the fight against neuroblastoma and other neuroendocrine tumors. In this work, we synthesized three dual-targeting BG-P400-TAT derivatives, dI-BG-P400-TAT, dM-BG-P400-TAT, and BG-P400-PAT containing di-iodobenzene, di-methoxybenzene, and piperazine groups, respectively. These derivatives utilize to norepinephrine transporter (NET) and the integrin αvß3 receptor to simultaneously modulate both targets based on evaluation in a neuroblastoma animal model using the neuroblastoma SK-N-F1 cell line. Among the three synthesized agents, the piperazine substituted BG-P400-PAT exhibited potent integrin αvß3 antagonism and reduced neuroblastoma tumor growth and cancer cell viability by >90%. In conclusion, BG-P400-PAT and derivatives represent a potential therapeutic approach in the management of neuroblastoma.


Asunto(s)
Antineoplásicos/farmacología , Diseño de Fármacos , Neuroblastoma/tratamiento farmacológico , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática/antagonistas & inhibidores , Tiroxina/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Ratones , Ratones Desnudos , Estructura Molecular , Neuroblastoma/metabolismo , Neuroblastoma/patología , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática/metabolismo , Relación Estructura-Actividad , Tiroxina/análogos & derivados , Tiroxina/química , Células Tumorales Cultivadas
18.
Environ Toxicol Chem ; 40(8): 2306-2318, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33822397

RESUMEN

Neonicotinoid insecticides (NNIs) are now popular in many agricultural systems across Africa; however, the extent of human exposures to NNIs in African countries is scarcely reported. The present study evaluates neonicotinoid exposures in the consumer population of Kumasi, a cosmopolitan city in Ghana. A total of 75 human urine samples were collected from healthy volunteers (nonfarmers, aged 13-80 yr) and analyzed with a liquid chromatography electrospray ionization tandem mass spectrometry system. Seven NNIs and 3 NNI metabolites were detected in the following pattern (frequency, median concentration, maximum concentration): N-dm-acetamiprid (94.7%, 0.41 µg/L, 8.79 µg/L) > imidacloprid (70.7%, 0.15 µg/L, 211.62 µg/L) > N-(6-chloro-3-pyridylmethyl)-N-ethyl-N'-methylformamidine (62.2%, 0.43 µg/L, 53.85 µg/L) > 2-[N-(6-chloro-3-pyridylmethyl)-N-ethylamino]-2-(methylimino)acetic acid (56.8%, 0.10 µg/L, 3.53 µg/L) > clothianidin (40%, >limit of quantification [LOQ], 0.45 µg/L) > nitenpyram (18.7%, >LOQ, 0.14 µg/L) ≈ thiamethoxam (18.7%, >LOQ, 0.21 µg/L) > dinotefuran (12.0%, >LOQ, 1.01 µg/L) > acetamiprid (2.7%, >LOQ, 0.08 µg/L) ≈ thiacloprid (2.7%, >LOQ, 0.14 µg/L). Approximately 92% of the subjects were found to be exposed to multiple neonicotinoids simultaneously. The mean, median, and maximum imidacloprid equivalent of the relative potency factor of NNIs were found to be 1.6, 0.5, and 22.52, respectively. The median estimated daily intakes of acetamiprid, imidacloprid, and nitenpyram were 0.47, 1.27, and 0.02 µg/kg/d for females and 0.91, 0.66, and 0.08 µg/kg/d for males, respectively. The maximum daily intakes of all the NNIs were <1% of their chronic reference doses (cRfDs), except for imidacloprid and thiacloprid which recorded maximum daily intakes corresponding to 17.97 and 8.28% of cRfDs, respectively. To the best of our knowledge, the present study is the first biomonitoring report on neonicotinoid insecticides in Africa. Environ Toxicol Chem 2021;40:2306-2318. © 2021 SETAC.


Asunto(s)
Insecticidas , Femenino , Ghana , Humanos , Insecticidas/análisis , Masculino , Neonicotinoides/análisis , Nitrocompuestos
19.
J Med Chem ; 64(9): 6300-6309, 2021 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-33886292

RESUMEN

We have previously reported that the αvß3 inhibitor P-bi-TAT, a bifunctional version of the thyroid hormone metabolite tetraiodothyroacetic acid (tetrac) conjugated to polyethylene glycol (PEG) MW 4000, has excellent efficacy in a glioblastoma multiforme (GBM) mouse model. However, bioanalysis problems due to PEG polydispersity and large-scale synthesis issues led to a search for new molecules, culminating in the discovery of fb-PMT, a conjugate of tetrac and monodisperse PEG36, with a lipophilic 4-fluorobenzyl group at the opposite end of the PEG chain. fb-PMT reduces GBM tumor growth and viability by up to 98%, is suitable for large-scale synthesis, and is amenable to bioanalysis using mass spectrometry-based detection. We also showed that changes in lipophilicity at the opposite end of the PEG chain from the active tetrac component affected the proton NMR chemical shift of the tetrac moiety in D20 and brain levels of the compound after subcutaneous dosing.


Asunto(s)
Ácido Acético/química , Ácido Acético/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Encéfalo/metabolismo , Glioblastoma/patología , Integrina alfaVbeta3/antagonistas & inhibidores , Ácido Acético/síntesis química , Ácido Acético/metabolismo , Animales , Antineoplásicos/síntesis química , Antineoplásicos/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Técnicas de Química Sintética , Glioblastoma/tratamiento farmacológico , Humanos , Ratones , Polietilenglicoles/química
20.
PLoS One ; 14(7): e0219208, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31260498

RESUMEN

OBJECTIVES: Neonicotinoid insecticides are widely used systemic pesticides with nicotinic acetylcholine receptor agonist activity that are a concern as environmental pollutants. Neonicotinoids in humans and the environment have been widely reported, but few studies have examined their presence in fetuses and newborns. The objective of this study is to determine exposure to neonicotinoids and metabolites in very low birth weight (VLBW) infants. METHODS: An analytical method for seven neonicotinoids and one neonicotinoid metabolite, N-desmethylacetamiprid (DMAP), in human urine using LC-ESI/MS/MS was developed. This method was used for analysis of 57 urine samples collected within 48 hours after birth from VLBW infants of gestational age 23-34 weeks (male/female = 36/21, small for gestational age (SGA)/appropriate gestational age (AGA) = 6/51) who were admitted to the neonatal intensive care unit of Dokkyo Hospital from January 2009 to December 2010. Sixty-five samples collected on postnatal day 14 (M/F = 37/22, SGA/AGA = 7/52) were also analyzed. RESULTS: DMAP, a metabolite of acetamiprid, was detected in 14 urine samples collected at birth (24.6%, median level 0.048 ppb) and in 7 samples collected on postnatal day 14 (11.9%, median level 0.09 ppb). The urinary DMAP detection rate and level were higher in SGA than in AGA infants (both p<0.05). There were no correlations between the DMAP level and infant physique indexes (length, height, and head circumference SD scores). CONCLUSION: These results provide the first evidence worldwide of neonicotinoid exposure in newborn babies in the early phase after birth. The findings suggest a need to examine potential neurodevelopmental toxicity of neonicotinoids and metabolites in human fetuses.


Asunto(s)
Contaminantes Ambientales/orina , Recién Nacido de muy Bajo Peso/orina , Insecticidas/orina , Exposición Materna/efectos adversos , Neonicotinoides/orina , Cromatografía Líquida de Alta Presión/métodos , Contaminantes Ambientales/metabolismo , Contaminantes Ambientales/toxicidad , Femenino , Humanos , Recien Nacido Extremadamente Prematuro/orina , Recién Nacido , Insecticidas/metabolismo , Insecticidas/toxicidad , Unidades de Cuidado Intensivo Neonatal , Masculino , Neonicotinoides/metabolismo , Neonicotinoides/toxicidad , Trastornos del Neurodesarrollo/etiología , Trastornos del Neurodesarrollo/prevención & control , Embarazo , Piridinas/metabolismo , Piridinas/toxicidad , Piridinas/orina , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos
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