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1.
Am J Physiol Cell Physiol ; 324(6): C1341-C1352, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37184231

RESUMO

Volumetric muscle loss (VML) causes irrecoverable loss of muscle mass and strength and results in permanent disability. VML injury shows extensive fibrosis, which impedes functional tissue regeneration. Our lab has created a biosponge scaffold composed of extracellular matrix (ECM) proteins (i.e., biosponge) that can enhance muscle regeneration and function following VML. In this work, a potent small molecule inhibitor of alpha v-subunit containing integrins known as IDL-2965 was incorporated into the biosponges for localized suppression of fibrosis post-VML. Our results demonstrate that local delivery of IDL-2965 via the biosponges attenuated the deposition of fibrotic tissue preceded by a downregulation of profibrotic genes in VML-injured muscles. The reduction in fibrotic tissue had no detrimental effects on muscle mass, function, size, or vascularity. Overall, these findings suggest that the codelivery of biosponges and IDL-2965 is a safe and effective strategy for the mitigation of fibrotic tissue deposition in VML-injured muscles.


Assuntos
Músculo Esquelético , Doenças Musculares , Humanos , Músculo Esquelético/metabolismo , Doenças Musculares/patologia , Cicatrização , Proteínas da Matriz Extracelular/metabolismo , Fibrose
2.
Chem Eng J ; 433(Pt 2)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36505940

RESUMO

Emerging perfluoroalkyl and polyfluoroalkyl substances contaminate waters at trace concentrations, thus rapid and selective adsorbents are pivotal to mitigate the consequent energy-intensive and time-consuming issues in remediation. In this study, coal combustion residuals-fly ash was modified (FA-SCA) to overcome the universal trade-off between high adsorption capacity and fast kinetics. FA-SCA presented rapid adsorption (teq = 2 min) of PFOX (perfluorooctanoic acid and perfluorooctanesulfonic acid, collectively), where the dynamic adsorption capacity (qdyn = qm/teq) was 2-3 orders of magnitude higher than that of benchmark activated carbons and anion-exchange resins. Investigated by advanced characterization and kinetic models, the fast kinetics and superior qdyn are attributed to (1) elevated external diffusion driven by the submicron particle size; (2) enhanced intraparticle diffusion caused by the developed mesoporous structure (Vmeso/Vmicro = 8.1); (3) numerous quaternary ammonium anion-exchange sites (840 µmol/g), and (4) appropriate adsorption affinity (0.031 L/µmol for PFOS, and 0.023 L/µmol for PFOA). Since the adsorption was proven to be a synergistic process of electrostatic and hydrophobic interactions, effective adsorption ([PFOX]ini = 1.21 µM, concentration levels of highly-contaminant-sites) was obtained at conventional natural water chemistries. High selectivity (>85.4% removal) was also achieved with organic/inorganic competitors, especially compounds with partly similar molecular structures to PFOX. In addition, >90% PFOX was removed consistently during five cycles in mild regeneration conditions (pH 12 and 50 °C). Overall, FA-SCA showed no leaching issues of toxic metals and exhibits great potential in both single-adsorption processes and treatment train systems.

3.
J Memb Sci ; 5992020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32095035

RESUMO

Perfluorochemicals (PFCs) are emerging contaminants in various water sources. Responsive polymers provide a new avenue for PFC adsorption/desorption from water. Poly-N-isopropylacrylamide's (PNIPAm's) temperature-responsive behavior and hydrophilic/hydrophobic transition is leveraged for reversible adsorption and desorption of PFCs. Adsorption of PFOA (perfluoro-octanoic acid) onto PNIPAm hydrogels yielded Freundlich distribution coefficients (Kd) of 0.073 L/g at 35 °C (above LCST) and 0.026 L/g at 22°C. Kinetic studies yielded second order rate constants (k2) of 0.012 g/mg/h for adsorption and 12.6 g/mg/h for desorption, with initial rates of 28 mg/g/h and 41 mg/g/h, respectively. Interaction parameters of PNIPAm's functional groups in its different conformational states, as well as the hydrophobic fluorinated carbon tails and hydrophilic head groups of PFOA are used to describe relative adsorption. Polyvinylidene difluoride (PVDF) provides a robust membrane structure for the commercial viability of polymeric adsorbents. Temperature swing adsorption of PFOA using PNIPAm functionalized PVDF membrane pores showed consistent adsorption and desorption capacity over 5 cycles. PFOA desorption percentage of 60% was obtained in pure water at temperatures below PNIPAm's lower critical solution temperature (LCST) while 13% desorption was obtained at temperatures above the LCST, thus showing the importance of the LCST on desorption performance.

4.
Antiviral Res ; 220: 105762, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37996012

RESUMO

Tropolone compounds can inhibit hepatitis B virus (HBV) replication at sub-micromolar levels and are synergistic upon co-treatment with nucleos(t)ide analog drugs. However, only a few compounds within this chemotype have been screened for their pharmacological properties. Here, we chose 36 structurally diverse tropolones from six subclasses to characterize their in vitro pharmacological parameters. All compounds were more soluble in pHs that reflect the gastrointestinal tract (pH 5 and 6.5) than plasma (pH 7.4). Those compounds that had solubility limits >100 µM were tested in a passive permeability assay, and there was no general trend in the compounds' passive permeability at any pH. Twenty-nine compounds with the best absorption parameters were tested in HEK293 cells to assess potential cytotoxicity; measured toxicities were similar to those in the hepatic HepDES19 cells used for screening (R2 = 0.55). Sixteen representative compounds were tested against five major CYP450 isoforms and there was no substantial inhibition by any compound against any of the enzymes tested (<50%). The t1/2 values of 15 compounds were determined in the microsome stability assay and 12 compounds were evaluated in plasma protein binding assays to assess factors affecting their rate of clearance. All compounds with detectable analyte peaks had t1/2 > 30 min, and while 4 of 12 had statistically significant decreased potency in conditions with increased albumin concentrations, only one compound's potency was biologically significant. These data indicate that the tropolones have pharmacological characteristics that reflect approved drugs and inform future structure activity relationships during drug design.


Assuntos
Vírus da Hepatite B , Tropolona , Humanos , Tropolona/farmacologia , Células HEK293 , Relação Estrutura-Atividade , Desenho de Fármacos , Antivirais/farmacologia
5.
Environ Toxicol Pharmacol ; 98: 104062, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36621559

RESUMO

Exposure to certain per-and polyfluoroalkyl substances (PFAS) has been shown to be positively associated with total and/or low-density lipoprotein cholesterol. Examining this association in lipid lowering interventions may provide additional evidence linking PFAS to cardiovascular risk. We examined the relationship of 6 PFAS with cholesterol in a 6-month lifestyle-based intervention. We quantitated PFAS in 350 individuals at baseline and post intervention and examined associations of PFAS with cholesterol before and after intervention. Food frequency questionnaires and GIS analyses were used to investigate PFAS hotspots and possible exposure routes. Cholesterol significantly decreased following intervention and in parallel, PFOS, PFOA, PFHxS, and PFHpA significantly decreased. PFOS was positively correlated with total cholesterol only post-intervention. We observed that PFOS was distributed among both non-albumin and albumin lipoprotein fractions pre-intervention, but entirely in albumin fraction post-intervention. Our results indicate that lipid-lowering via lifestyle modification may impact on circulating levels or distribution of PFAS.


Assuntos
Ácidos Alcanossulfônicos , Poluentes Ambientais , Fluorocarbonos , Humanos , Colesterol , LDL-Colesterol , Estilo de Vida
6.
Environ Int ; 158: 106907, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34763231

RESUMO

BACKGROUND: Residents of Anniston Alabama were highly exposed to polychlorinated biphenyls (PCBs) due to longstanding manufacturing in the area. The Anniston Community Health Surveys (ACHS I-2005-2007 and II, 2014) have linked these exposures with a variety of deletereous health outcomes. In addition to PCBs, these individuals were likely simultaneously exposed to other persistent organic pollutants including per and polyfluoroalkyl substances (PFAS), which are an emerging class of ubiquitous industrial chemicals that are measurable in the blood of most individuals and have themselves been linked increased risk of some non communicable diseases. METHODS: To characterize PFAS exposures in ACHS I and ACHS II, we measured eight environmentally significant PFAS in serum by UPLC coupled electrospray ionization tandem mass spectrometry. Perfluorooctane sulfonate (PFOS), Perfluorooctanoic acid (PFOA), Perfluorononanoate (PFNA), Perfluorohexane sulfonate (PFHxS), Perfluoroheptanoic acid (PFHpA), Perfluorobutanesulfonic acid (PFBS), Hexafluoropropylene oxide dimer acid (HFPO-DA), and 4:2 Fluorotelomer sulfonic acid (4.2 FTS) were extracted from matched serum samples of individuals who participated in the original ACHS I (2005-2007; n = 297) and the follow up ACHS II (2014; n = 336). Data were collected in negative multiple reaction monitoring (MRM) mode with monitoring of quantitation and qualifier ions for all target PFAS analytes, surrogates and internal standards. VARCLUS procedure was used to create hierarchical clusters between PFAS and other legacy persistent organic pollutants which may share similar exposure routes. RESULTS: Overall, circulating PFAS levels decreased approximately 50% from ACHS I (2005-2007) to ACHS II (2014), but these changes varied by compound. Mean levels of PFOS were >3 times higher in ACHS I subjects than in conpemporaneous NHANES subjects (2005-2006; ACHS I mean: 71.1 ng/ml; NHANES mean: 20.2 ng/mL), and this relationship persisted in ACHS II subjects (2014: ACHS II mean: 34.7 ng/ml; NHANES mean: 5.92 ng/mL). PFNA was also higher in both ACHS I and ACHS II subjects in comparision to NHANES whereas levels of PFOA and PFHxS were lower than in NHANES. Finally, cluster analysis revealed that in ACHS II, most PFAS tracked with polybrominated diphenyl ethers, except PFNA and PFHpA which clustered with industrial PCBs. In ACHS I, PFAS analytes correlated more closely with industrial PCBs and chlorinated pesticides. CONCLUSIONS: Participants in the Anniston Community Health Surveys have higher levels of PFOS and PFNA than the general population with average PFOS levels >3 times contemporaneous NHANES levels. Since PFAS were not known to be manufactured in the area, more work needs to be completed to determine if population demographics, proximity to a military base, or regional manufacturing can explain the elevated levels.


Assuntos
Ácidos Alcanossulfônicos , Poluentes Ambientais , Fluorocarbonos , Bifenilos Policlorados , Inquéritos Epidemiológicos , Humanos , Inquéritos Nutricionais , Saúde Pública
7.
Eur J Med Chem ; 238: 114443, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35635945

RESUMO

We previously showed that the anti-fungal drug ciclopirox olamine effectively inhibits replication of herpes simplex virus (HSV)-1 and HSV-2. Given the rise of HSV strains that are resistant to nucleos(t)ide analog treatment, as well as the incomplete efficacy of nucleos(t)ide analogs, new inhibitory compounds must be explored for potential use in the treatment of HSV infection. In the present study, we analyzed 44 compounds derived from the core structure of ciclopirox olamine for inhibitory activity against HSV. Thirteen of these derivative compounds inhibited HSV-2 replication by > 1000- to ∼100,000-fold at 1 µM and displayed EC50 values lower than that of acyclovir, as well as low cytotoxicity, indicating their strong therapeutic potential. Through structural comparison, we also provide evidence for the importance of various structural motifs to the efficacy of ciclopirox and its derivatives, namely hydrophobic groups at R4 and R6 of the ciclopirox core structure. Like ciclopirox, representative analogs exhibit some oral bioavailability but are rapidly cleared in vivo. Together, these results will guide further development of N-hydroxypyridones as HSV therapeutics.


Assuntos
Herpes Simples , Herpesvirus Humano 1 , Aciclovir/química , Aciclovir/farmacologia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Antivirais/uso terapêutico , Ciclopirox/farmacologia , Ciclopirox/uso terapêutico , Herpes Simples/tratamento farmacológico , Herpesvirus Humano 2 , Humanos , Replicação Viral
8.
J Chromatogr A ; 1653: 462426, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34352431

RESUMO

We developed and validated a method for direct determination of per- and polyfluoroalkylated substances (PFASs) in environmental water samples without prior sample concentration. Samples are centrifuged and supernatants passed through an Acrodisc Filter (GXF/GHP 0.2  um, 25  mm diameter). After addition of ammonium acetate, samples are analyzed by UPLC-MS/MS using an AB Sciex 6500 plus Q-Trap mass spectrometer operated in negative multiple reaction-monitoring (MRM) mode. The instrument system incorporates a delay column between the pumps and autosampler to mitigate interference from background PFAS. The method monitors eight short-/long-chain PFAS which are identified by monitoring specific precursor product ion pairs and by their retention times and quantified using isotope mass-labeled internal standard based calibration plots. Average spiked recoveries (n = 8) of target analytes ranged from 84 to 110% with 4-9% relative standard deviation (RSD). The mean spiked recoveries (n = 8) of four surrogates were 94-106% with 3-8% RSD. For continuous calibration verification (CCV), average spiked recoveries (n = 8) for target analytes ranged from 88 to 114% with 4-11% RSD and for surrogates ranged from 104-112% with 3-11% RSD. The recoveries (n = 6) of matrix spike (MX), matrix spike duplicate (MXD), and field reagent blank (FRB) met our acceptance criteria. The limit of detection for the target analytes was between 0.007 and 0.04 ng/mL. The method was used to measure PFAS in tap water and surface water.


Assuntos
Cromatografia Líquida , Água Potável , Fluorocarbonos , Espectrometria de Massas em Tandem , Extração em Fase Sólida
9.
J Anal Toxicol ; 44(4): 339-347, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-31776573

RESUMO

Per- and poly-fluorinated alkyl substances (PFASs) are a large group of synthetic surfactant chemicals with widespread uses in food packaging and textile manufacturing and as the main constituent of aqueous film-forming firefighting foams. PFASs are highly persistent in the environment, and human exposures are extensive with these chemicals detectable in the blood of almost all adult Americans. PFASs exhibit a range of toxic effects in preclinical models. In humans, PFAS exposure has been associated with lower birth weights, decreased immune responses, cancer and impaired fertility and elevated circulating cholesterol levels. We have developed a sensitive high-throughput method for quantification of representative PFAS in human serum and plasma for biomonitoring and epidemiological studies of human health effects of PFAS exposure. The method combines robust and reproducible 96-well plate format sample preparation with ultra-performance liquid chromatography-tandem mass spectrometry. The method was developed, validated and used for targeted measurements of eight short-/long-chain PFAS analytes in human serum. Targeted analytes were measured in 50 microliters of sample using mass-labeled internal standards. Mean spiked recoveries (n = 10) of target analytes for three tiers quality control (QC-low, QC-medium, QC-high) samples ranged from 70 to 127% with 2-14% relative standard deviation (RSD). The average spiked recoveries (n = 10) of surrogates were 79-115% with 8-12% RSD for QC-low, 90-123% with 7-12% RSD for QC-medium and 82-114% with 9-15% RSD for QC-high. The limit of detection for the target compounds was 0.05-0.04 ng/mL. The method was used to reveal regional differences in PFAS exposures in Kentucky residents receiving care at the University of Kentucky Hospitals.


Assuntos
Poluentes Ambientais/sangue , Fluorocarbonos/sangue , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Humanos , Plasma , Extração em Fase Sólida , Espectrometria de Massas em Tandem
10.
Membranes (Basel) ; 11(1)2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33375603

RESUMO

Nanomaterials with tunable properties show promise because of their size-dependent electronic structure and controllable physical properties. The purpose of this research was to develop and validate environmentally safe nanomaterial-based approach for treatment of drinking water including removal and degradation of per- and polyfluorinated chemicals (PFAS). PFAS are surfactant chemicals with broad uses that are now recognized as contaminants with a significant risk to human health. They are commonly used in household and industrial products. They are extremely persistent in the environment because they possess both hydrophobic fluorine-saturated carbon chains and hydrophilic functional groups, along with being oleophobic. Traditional drinking water treatment technologies are usually ineffective for the removal of PFAS from contaminated waters, because they are normally present in exiguous concentrations and have unique properties that make them persistent. Therefore, there is a critical need for safe and efficient remediation methods for PFAS, particularly in drinking water. The proposed novel approach has also a potential application for decreasing PFAS background levels in analytical systems. In this study, nanocomposite membranes composed of sulfonated poly ether ether ketone (SPEEK) and two-dimensional phosphorene were fabricated, and they obtained on average 99% rejection of perfluorooctanoic acid (PFOA) alongside with a 99% removal from the PFOA that accumulated on surface of the membrane. The removal of PFOA accumulated on the membrane surface achieved 99% after the membranes were treated with ultraviolet (UV) photolysis and liquid aerobic oxidation.

11.
Environ Pollut ; 261: 114183, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32105967

RESUMO

Exposure to some environmental pollutants increases the risk of developing inflammatory disorders such as steatosis and cardiometabolic diseases. Diets high in fermentable fibers such as inulin can modulate the gut microbiota and lessen the severity of pro-inflammatory diseases, especially in individuals with elevated circulating cholesterol. Thus, we aimed to test the hypothesis that hyperlipidemic mice fed a diet enriched with 8% inulin would be protected from the pro-inflammatory toxic effects of PCB 126. Four groups of male Ldlr-/- mice were fed a high cholesterol diet containing 8% inulin or 8% cellulose (control) for 12 weeks. At weeks 2 and 4, mice were exposed to PCB 126 or vehicle (control). PCB 126 exposure induced wasting and impaired glucose tolerance, which were attenuated by inulin consumption. PCB 126 exposure induced hepatic lipid accumulation and increased inflammatory gene expression, which were both decreased by inulin consumption. In addition, inulin feeding decreased atherosclerotic lesion development in the aortic root and modulated the expression of enzymes related to glycolysis. Finally, 16S rRNA sequencing of gut microbial populations showed that PCB 126 modulated multiple microbiota genera (e.g., 3-fold decrease in Allobaculum and 3-fold increase in Coprococcus) which were normalized in inulin fed mice. Overall our data support the hypothesis that a dietary intervention that targets the gut microbiota may be an effective means of attenuating dioxin-like pollutant-mediated diseases.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Dioxinas , Microbioma Gastrointestinal , Animais , Disbiose , Inulina , Masculino , Camundongos , Bifenilos Policlorados , Prebióticos , RNA Ribossômico 16S
12.
Chemosphere ; 172: 89-95, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28063319

RESUMO

The Tri-State Mining District of Missouri, Kansas and Oklahoma was the site of large-scale mining operations primarily for lead and zinc until the mid-1950s. Although mining across the area has ceased, high concentrations of heavy metals remain in the region's soil and water systems. The town of Picher, Ottawa County, OK, lies within this district and was included in the Tar Creek Superfund Site by the U.S. Environmental Protection Agency in 1980 due to extensive contamination. To elucidate the extent of heavy-metal contamination, a soil-chemistry survey of the town of Picher was conducted. Samples (n = 111) were collected from mine tailings, locally known as chat, in Picher and along cardinal-direction transects within an 8.05-km radius of the town in August 2015. Samples were analyzed for soil pH, moisture, and metal content. Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) analyses of 20 metals showed high concentrations of lead (>1000 ppm), cadmium (>40 ppm) and zinc (>4000 ppm) throughout the sampled region. Soil moisture content ranged from 0.30 to 35.9%, and pH values ranged from 5.14 to 7.42. MANOVA of metal profiles determined that soils collected from the north transect and chat were significantly different (p < 0.01) than other sampled directions. Lead, cadmium and zinc were correlated with one another. These data show an unequal distribution of contamination surrounding the Picher mining site. Mapping heavy-metal contamination in these soils represents the first step in understanding the distribution of these contaminants at the Picher mining site.


Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , Monitoramento Ambiental/métodos , Locais de Resíduos Perigosos , Mineração , Oklahoma
13.
Food Chem ; 190: 529-536, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26213006

RESUMO

Occurrences of pharmaceuticals are evident in aquatic organisms. A reproducible gas chromatography-mass spectrometry (GC-MS) method using selected ion monitoring (SIM) has been used to determine the anti-histamine diphenhydramine (DPH), anti-anxiety diazepam (DZP), anti-seizure carbamazepine (CZP) drugs and their metabolites in grocery stores fish that were homogenized, extracted, pre-concentrated, cleaned up, and examined. Identifications of the compounds in extracts were obtained by comparing similar mass spectral features and retention properties with standards. Among nine frequently detected drugs, only DPH and DZP were observed and ranged from 0.61 to 6.21 and 1.99 to 16.57 ng/g, respectively, in fourteen fish species. These concentration values were lower than the environmental fish. Mean spike recoveries of analytes exceeded 75% with relative standard deviations (RSD)<10%. The statistically-derived method detection limits (MDLs) for nine compounds ranged from 0.13 to 5.56 ng/g. Average surrogate recoveries were 80-85% with 4-9% RSD.


Assuntos
Peixes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Animais , Soluções Farmacêuticas
14.
Aquat Toxicol ; 106-107: 164-72, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22172543

RESUMO

Ubiquitous occurrences of synthetic nitro musks are evident in the literature. The in vivo analysis of musk xylene (MX) and musk ketone (MK)-protein adducts in trout liver has been performed by gas chromatography-mass spectrometry using selected ion monitoring (GC-SIM-MS). Biotransformation, dose-response and toxicokinetics studies of 2-amino-MX (2-AMX), 2-amino-MK (2-AMK) and 4-amino-MX (4-AMX) metabolites, covalently bound to cysteine amino acids in proteins in fish liver, formed by enzymatic nitro-reduction of MX and MK, have been described. Trouts were exposed to single exposures of 0.010, 0.030, 0.10, and 0.30 mg/g MX and/or MK. Forty-two fish liver samples were collected from exposed- and control-fish subsequent to exposure intervals of 1 day, 3 days, and 7 days and were composited as per exposure schedules and times. Alkaline hydrolysis released bound metabolites from exposed liver composites that were extracted into n-hexane and then concentrated and analyzed by GC-SIM-MS. The presence of the metabolites in liver extracts was confirmed based on agreement of similar mass spectral properties and retention times with standards. In the dose-response study, the maximum adduct formation was 492.0 ng/g for 2-AMX, 505.5 ng/g for 2-AMK and 12588.5 ng/g for 4-AMX in liver at 0.03 mg/g MX and MK fish in 1 day after exposure. For toxicokinetics investigation, the highest amount of the target metabolites was found to be the same concentration as observed in the dose-response study for 1 day after exposure with 0.03 mg/g MX and MK fish and the half-lives of the metabolites were estimated to be 2-9 days based on assumption of first-order kinetics. Average recoveries exceeded 95% with a relative standard deviation (RSD) around 9%, and the limit of detection (LOD) ranged from 0.91 to 3.8 ng/g based on a signal to noise ratio of 10 (S/N=10) could be achieved for the metabolites. No metabolites were detected in the controls and exposed non-hydrolyzed liver extracts. This is the first report on dose-response and toxicokinetics of nitro musk-cysteine-protein adducts in fish liver.


Assuntos
Exposição Ambiental/análise , Fígado/metabolismo , Poluentes Químicos da Água/toxicidade , Xilenos/toxicidade , Biomarcadores/metabolismo , Biotransformação , Relação Dose-Resposta a Droga , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Poluentes Químicos da Água/química , Poluentes Químicos da Água/metabolismo , Xilenos/química , Xilenos/metabolismo
15.
Nat Prod Commun ; 7(9): 1203-8, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23074909

RESUMO

Bitter melon (Momordica charantia) seed extracts (BMSE) have been used as traditional medicine for treating various ailments, although in many cases, the active component(s) are unidentified. In this study, bitter melon seeds were extracted in water, ethanol, or ethanol: water (1:1). The aqueous seed extracts (BMSE-W) exhibited marked cytotoxicity towards human embryonic kidney 293T (HEK293T) and human colon tumor 116 (HCT1116) cells. The activity in BMSE-W was unaffected by heat and proteinases treatments, and eluted in the total volume of size-exclusion HPLC, suggesting the small, organic nature of the active component(s). Gas chromatographic-mass spectrometic (GC-MS) analysis of the HPLC fractions identified methoxy-phenyl oxime (MPO) as a major active component. Acetophenone oxime, a commercially available structural homolog of MPO, demonstrated cytotoxicity comparable with that of the BMSE-W. The oxime functional group was found to be critical for activity. Increased poly-(ADP-ribose)-polymerase and beta-actin cleavage, and chromatin condensation observed in treated cells suggested apoptosis as a plausible cause for the cytotoxicity. This study, for the first time, identified a cytotoxic oxime in BMSE-W.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Momordica charantia/química , Extratos Vegetais/farmacologia , Apoptose/efeitos dos fármacos , Células HCT116 , Células HEK293 , Humanos , Sementes/química
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