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1.
EBioMedicine ; 102: 105042, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38471990

RESUMO

BACKGROUND: An ongoing important need exists to rapidly develop novel therapeutics for COVID-19 that will retain antiviral efficacy in the setting of rapidly evolving SARS-CoV-2 variants and potential future development of resistance of SARS-COV-2 to remdesivir and protease inhibitors. To date, there is no FDA-approved treatment for post-exposure prophylaxis against SAR-CoV-2. We have shown that the mitochondrial antioxidant mitoquinone/mitoquinol mesylate (Mito-MES), a dietary supplement, has antiviral activity against SARS-CoV-2 in vitro and in SARS-CoV-2 infected K18-hACE2 mice. METHODS: In this exploratory, pragmatic open label clinical trial (ClinicalTrials.gov identifier NCT05381454), we studied whether Mito-MES is an effective post-exposure prophylaxis treatment in people who had high-grade unmasked exposures to SARS-CoV-2 within 5 days prior to study entry. Participants were enrolled in real-world setting in Los Angeles, United States between May 1 and December 1, 2022 and were assigned to either mito-MES 20 mg daily for 14 days (n = 40) or no mito-MES (controls) (n = 40). The primary endpoint was development of SARS-CoV-2 infection based on 4 COVID-19 diagnostic tests [rapid antigen tests (RATs) or PCR] performed during the study period (14 days post exposure). FINDINGS: Out of 40 (23 females; 57.5%) study participants who took Mito-MES, 12 (30%) developed SARS-CoV-2 infection compared to 30 of the 40 controls (75%) (difference -45.0%, 95% confidence intervals (CI): -64.5%, -25.5%). Out of 40 (19 females; 47.5%) study participants in the control group, 30 (75.0%) had at least one positive COVID-19 diagnostic test and 23 (57.5%) were symptomatic. With regards to key secondary outcomes, among symptomatic SARS-CoV-2 infections, the median duration of viral symptoms was lower in the Mito-MES group (median 3.0, 95% CI 2.75, 3.25) compared to the control group (median 5.0, 95% CI 4.0, 7.0). None of the study participants was hospitalized or required oxygen therapy. Mito-MES was well tolerated and no serious side effect was reported in any study participant. INTERPRETATION: This work describes antiviral activity of mito-MES in humans. Mito-MES was well tolerated in our study population and attenuated transmission of SARS-CoV-2 infection. Given established safety of Mito-MES in humans, our results suggest that randomized control clinical trials of Mito-MES as post-exposure prophylaxis against SARS-CoV-2 infection are warranted. FUNDING: This work was supported in part by National Institutes of Health grant R01AG059501 (TK), National Institutes of Health grant R01AG059502 04S1 (TK), NIH/National Center for Advancing Translational Sciences (NCATS) UCLA CTSI Grant Number UL1TR001881 and California HIV/AIDS Research Program grant OS17-LA-002 (TK).


Assuntos
COVID-19 , Compostos Organofosforados , Ubiquinona , Animais , Feminino , Humanos , Camundongos , Antivirais , COVID-19/prevenção & controle , Profilaxia Pós-Exposição , SARS-CoV-2 , Resultado do Tratamento , Ubiquinona/análogos & derivados
2.
Exp Gerontol ; 189: 112402, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38484905

RESUMO

BACKGROUND: This study aimed to investigate the effects of combined alpha-lipoic acid (ALA) and mitoquinone (Mito Q) supplementation on cardiac function and the underlying mechanisms in aged rats with myocardial infarction (MI). METHODS: The aged rats underwent left anterior descending artery (LADA) occlusion for 30 min, followed by reperfusion for 24 h. ALA (100 mg/kg, gavage) and Mito Q (10 mg/kg, IP) were administered daily for two weeks before ischemia. Cardiac function, inflammatory, and apoptotic markers were evaluated 24 h after ischemia. RESULTS: The results of this study indicated that the administration of the combination of ALA and Mito Q significantly improved cardiac function. This improvement was linked to a reduction in the expression of pro-inflammatory cytokines TNF-α, IL-6, and IL-1ß (P < 0.001) and apoptotic markers (Bax, caspase-3, and Cyt-c), as well as a decrease in the percentage of TUNEL-positive cells (P < 0.001). CONCLUSION: The study revealed that combined intervention synergistically mitigated cardiac dysfunction by suppressing inflammatory and apoptotic pathways in aged rats with MI. Further research is needed to validate the potential of ALA and Mito Q as therapeutic options for elderly people at risk of heart attacks.


Assuntos
Infarto do Miocárdio , Compostos Organofosforados , Ácido Tióctico , Ubiquinona/análogos & derivados , Humanos , Idoso , Ratos , Animais , Ácido Tióctico/farmacologia , Ácido Tióctico/uso terapêutico , Ratos Sprague-Dawley , Infarto do Miocárdio/tratamento farmacológico , Suplementos Nutricionais , Apoptose
3.
Food Funct ; 15(4): 2131-2143, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38305460

RESUMO

The enhancement of bioavailability of food bioactive compounds as dietary supplements can be achieved through the development of targeted delivery systems. This study aimed to develop a novel dual-targeted delivery system for hepatocytes and mitochondria using phacoemulsification self-assembly. The delivery systems were engineered by modifying whey protein isolate (WPI) with galactose oligosaccharide (GOS) and triphenylphosphonium (TPP) to improve AXT transport to the liver and promote hepatic well-being. The dual-targeted nanoparticles (AXT@TPP-WPI-GOS) significantly reduced reactive oxygen species in in vitro experiments, thereby slowing down apoptosis. The AXT@TPP-WPI-GOS exhibited a prominent mitochondrial targeting capacity with a Pearson correlation coefficient of 0.76 at 4 h. In vivo pharmacokinetic experiments revealed that AXT@TPP-WPI-GOS could enhance AXT utilization by 28.18 ± 11.69%. Fluorescence imaging in mice demonstrated significantly higher levels of AXT@TPP-WPI-GOS accumulation in the liver compared to that of free AXT. Therefore, these nanoparticles hold promising applications in nutrient fortification, improving the bioavailability of AXT and supporting hepatic well-being.


Assuntos
Nanopartículas , Compostos Organofosforados , Estresse Oxidativo , Camundongos , Animais , Suplementos Nutricionais , Hepatócitos , Xantofilas
4.
J Environ Manage ; 350: 119584, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38035501

RESUMO

The growing demand for pesticide manufacturing and increasing public awareness of sustainable development, have let to urgent requirements for a refined environmental management framework. It is imperative to conduct process-based life cycle assessments (LCAs) to promote clean and environment-friendly technologies. Herein, the cradle-to-gate LCA of glyphosate production was executed as an example to investigate crucial production factors (materials or energy) and multiple environmental impacts during the production processes. Results showed that methanol caused the highest environmental damage in terms of toxicity, with a normalized value of 85.7 × 10-8, followed by coal-fired electricity in 6.00 × 10-8. Furthermore, optimized schemes were proposed, including energy improvement (electricity generated by switching from coal-fired power to solar power) and wastewater targeted conversion. Regarding the normalization results before and after optimization, the latter showed more significant results with the normalized value decreasing by 21.10 × 10-8, while that of the former only decreased by 6.50 × 10-8. This study provides an integrated LCA framework for organophosphorus pesticides (OPs) from upstream control and offers an important supplement to managing the key pollution factors and control links of the OP industry. Moreover, it reveals the positive influence of optimized schemes in facilitating cleaner production technologies, thus ultimately promoting new methodologies for resource recycling.


Assuntos
Praguicidas , Animais , Compostos Organofosforados , Carvão Mineral , Estágios do Ciclo de Vida
5.
Theriogenology ; 216: 8-11, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38142498

RESUMO

Supplementing the semen extender with some antioxidants may preserve sperm quality following liquid preservation. The aim of the current study was to evaluate the influence of the use of MitoQ in the semen extender on quality parameters and fertility of liquid-preserved ram semen. In this study, diluted semen samples were divided into five parts and supplemented with 0, 1, 10, 100 and 1000 nM MitoQ. The prepared samples were stored at 3-5 °C for up to 50 h. Motility, viability, mitochondrial activity, membrane integrity, and malondialdehyde concentration of the chilled sperm were assessed at 0, 25, and 50 h. To evaluate reproductive performance, artificial insemination was performed with semen liquid-preserved for 25 h. In results, at 0 h, no difference between the groups was observed. The use of 10 and 100 nM MitoQ resulted in higher (P ≤ 0.05) total motility, progressive motility, membrane integrity, mitochondrial activity, viability, and lower malondialdehyde concentration than the other groups after 25- and 50-h storage. Pregnancy, parturition and lambing rates were higher (P ≤ 0.05) when ewes were inseminated with 25-h chilled semen samples containing 10 and 100 nM MitoQ compared to the control. Therefore, supplementing the semen extender with MitoQ (10 and 100 nM) could be an efficient method to improve the quality and fertility rate of liquid-preserved ram semen.


Assuntos
Compostos Organofosforados , Preservação do Sêmen , Sêmen , Ubiquinona/análogos & derivados , Gravidez , Ovinos , Animais , Masculino , Feminino , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Espermatozoides , Fertilidade , Malondialdeído , Motilidade dos Espermatozoides , Análise do Sêmen/veterinária
6.
J Assist Reprod Genet ; 41(2): 371-383, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38146030

RESUMO

PURPOSE: Oxidative stress and mitochondrial dysfunction play central roles in reduced oocyte quality and infertility in obese patients. Mitochondria-targeted treatments containing co-enzyme Q10 such as mitoquinone (MitoQ) can increase mitochondrial antioxidative capacity; however, their safety and efficiency when supplemented to oocytes under lipotoxic conditions have not been described. METHODS: We tested the effect of different concentrations of MitoQ or its cationic carrier (TPP) (0, 0.1, 0.5, 1.0 µM each) during bovine oocyte IVM. Then, we tested the protective capacity of MitoQ (0.1 µM) against palmitic acid (PA)-induced lipotoxicity and mitochondrial dysfunction in oocytes. RESULTS: Exposure to MitoQ, or TPP only, at 1 µM significantly (P<0.05) reduced oocyte mitochondrial inner membrane potential (JC-1 staining) and resulted in reduced cleavage and blastocyst rates compared with solvent control. Lower concentrations of MitoQ or TPP had no effects on embryo development under control (PA-free) conditions. As expected, PA increased the levels of MMP and ROS in oocytes (CellROX staining) and reduced cleavage and blastocyst rates compared with the controls (P<0.05). These negative effects were ameliorated by 0.1 µM MitoQ. In contrast, 0.1 µM TPP alone had no protective effects. MitoQ also normalized the expression of HSP10 and TFAM, and partially normalized HSP60 in the produced blastocysts, indicating at least a partial alleviation of PA-induced mitochondrial stress. CONCLUSION: Oocyte exposure to MitoQ may disturb mitochondrial bioenergetic functions and developmental capacity due to a TPP-induced cationic overload. A fine-tuned concentration of MitoQ can protect against lipotoxicity-induced mitochondrial stress during IVM and restore developmental competence and embryo quality.


Assuntos
Técnicas de Maturação in Vitro de Oócitos , Doenças Mitocondriais , Compostos Organofosforados , Ubiquinona/análogos & derivados , Humanos , Animais , Bovinos , Técnicas de Maturação in Vitro de Oócitos/métodos , Oócitos , Blastocisto/metabolismo , Desenvolvimento Embrionário , Mitocôndrias/metabolismo
7.
Int J Mol Sci ; 24(21)2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37958950

RESUMO

In recent years, the phenomenon of acute poisoning and organ damage caused by organophosphorus pesticides (OPs) has been a frequent occurrence. Chlorpyrifos (CPF) is one of the most widely used organophosphorus pesticides. The main active components of ginseng stems and leaves are total ginseng stem-and-leaf saponins (GSLSs), which have various biological effects, including anti-inflammatory, antioxidant and anti-tumor activities. We speculate that these could have great potential in the treatment of severe diseases and the relief of organophosphorus-pesticide-induced side effects; however, their mechanism of action is still unknown. At present, our work aims to evaluate the effects of GSLSs on the antioxidation of CPF in vivo and in vitro and their potential pharmacological mechanisms. Mice treated with CPF (5 mg/kg) showed severe intestinal mucosal injury, an elevated diamine oxidase (DAO) index, the decreased expression of occlusive protein-1 (ZO-1) and occlusive protein, an impaired intestinal mucosal oxidation system and intestinal villi relaxation. In addition, chlorpyrifos exposure significantly increased the contents of the inflammatory factor TNF-α and the oxidative-stress-related indicators superoxide dismutase (SOD), catalase (CAT), glutathione SH (GSH), glutathione peroxidase (GSH-PX), reactive oxygen species (ROS) and total antioxidant capacity (T-AOC); elevated the level of lipid peroxide malondialdehyde (MDA); reversed the expression of Bax and caspase; and activated NF-κB-related proteins. Interestingly, GSLS supplementation at doses of 100 and 200 mg/kg significantly reversed these changes after treatment. Similar results were observed in cultured RAW264.7 cells. Using flow cytometry, Hoechst staining showed that GSLSs (30 µg/mL, 60 µg/mL) could improve the cell injury and apoptosis caused by CPF and reduce the accumulation of ROS in cells. In conclusion, GSLSs play a protective role against CPF-induced enterotoxicity by inhibiting NF-κB-mediated apoptosis and alleviating oxidative stress and inflammation.


Assuntos
Clorpirifos , Panax , Praguicidas , Saponinas , Camundongos , Animais , Clorpirifos/toxicidade , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , NF-kappa B/metabolismo , Panax/metabolismo , Saponinas/farmacologia , Compostos Organofosforados/farmacologia , Praguicidas/farmacologia , Estresse Oxidativo , Glutationa/metabolismo , Apoptose , Folhas de Planta/metabolismo
8.
Sci Total Environ ; 905: 167057, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37709080

RESUMO

Many anthropogenic chemicals are manufactured and eventually enter the surrounding environment, threatening food security and human health. Considering the additive or synergistic effects of pollutant mixtures, there is an expanding need for rapid, cost-effective and field-portable screening methods in environmental monitoring. This study used a recently developed biospectroscopy-bioreporter-coupling (BBC) approach to investigate the binary toxicity of Ag(I), Cr(VI) and four organophosphorus pesticides (dichlorvos, parathion, omethoate and monocrotophos). Ag(I) and Cr(VI) altered the toxicity mechanisms of pesticides, explained by the synergistic or antagonistic effect of Ag/Cr-induced cytotoxicity and pesticide-induced genotoxicity. The discriminating Raman spectral peaks associated with organophosphorus pesticides were 1585 and 1682 cm-1, but 750, 1004, 1306 and 1131 cm-1 were found in heavy metal and pesticide mixtures. More spectral alterations were related to pesticides rather than Ag(I) or Cr(VI), hinting at the dominant toxicity mechanisms of pesticides in mixtures. Ag(I) supplement significantly increased the levels of reactive oxygen species induced by organophosphorus pesticides, attributing to the increased permeability of cell membrane and entrance of toxic substances into the cells by the oligodynamic actions. This study lends deeper insights into the interactions between microbes and pollutant mixtures, offering clues to assess the cocktail effects of multiple pollutants comprehensively.


Assuntos
Poluentes Ambientais , Metais Pesados , Praguicidas , Humanos , Praguicidas/toxicidade , Compostos Organofosforados/toxicidade , Metais Pesados/toxicidade , Poluentes Ambientais/toxicidade
9.
Anal Chem ; 95(40): 14914-14924, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37769195

RESUMO

Credible and on-site detection of organophosphorus pesticides (OPs) in complex matrixes is significant for food security and environmental monitoring. Herein, a novel COF/methylene blue@MnO2 (COF/MB@MnO2) composite featured abundant signal loading, a specific recognition unit, and robust oxidase-like activity was successfully prepared through facile assembly processes. The multifunctional composite acted as a homogeneous electrochemical and photothermal dual-mode sensing platform for OPs detection through stimuli-responsive regulation. Without the presence of OPs, the surface MnO2 coating could recognize thiocholine (TCh), originating from acetylcholinesterase (AChE)-catalyzed hydrolysis of acetylthiocholine (ATCh), and exhibited a distinctly amplified diffusion current due to the release of plentiful MB; while the residual MnO2 nanosheets could only catalyze less TMB into oxidized TMB (oxTMB) with a typical near-infrared (NIR) absorption, enabling NIR-driven photothermal assay with a low temperature using a portable thermometer. Based on the inhibitory effect of OPs on AChE activity and OP-regulated generation of TCh, chlorpyrifos as a model target can be accurately detected with a low limit of detection of 0.0632 and 0.108 ng/mL by complementary electrochemical and photothermal measurements, respectively. The present dual-mode sensor was demonstrated to be excellent for application to the reliable detection of OPs in complex environmental and food samples. This work can not only provide a complementary dual-mode method for convenient and on-site detection of OPs in different scenarios but also expand the application scope of the COF-based multifunctional composite in multimodal sensors.


Assuntos
Técnicas Biossensoriais , Praguicidas , Compostos Organofosforados , Acetilcolinesterase , Azul de Metileno , Compostos de Manganês , Óxidos , Técnicas Biossensoriais/métodos
10.
J Chromatogr A ; 1708: 464339, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37660557

RESUMO

Design and preparation of new fiber coatings for solid-phase microextraction (SPME) is of significance to the sample preparation techniques. Herein, a facile strategy has been developed for the integration of the black phosphorus (BP) nanosheets with metal-organic framework (ZIF-8) to generate a BP/ZIF-8 nanocomposite. For the first time, the newly-synthesized BP/ZIF-8 nanocomposite was adopted as the SPME fiber coating for the extraction of organophosphorus pesticides (OPPs). Under the optimized conditions, the BP/ZIF-8 based SPME method gained acceptable linearity (0.04-20 µg L-1), low limits of detection (0.012-0.051 µg L-1) and good repeatability (3.2-8.1%). Coupled with gas chromatography-mass spectrometric detection, the developed SPME method was successfully used for the preconcentration of OPPs from environmental waters with the method recoveries from 92.0%-103.8%. This method offers a good alternative for the analysis of trace OPPs in environmental water samples.


Assuntos
Nanocompostos , Praguicidas , Zeolitas , Compostos Organofosforados , Microextração em Fase Sólida , Fósforo
11.
Cancer Epidemiol ; 85: 102410, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37413804

RESUMO

BACKGROUND: In the United States (US), the average annual increase in the incidence of prostate cancer (PCa) has been 0.5% between 2013 and 2017. Although some modifiable factors have been identified as the risk factors for PCa, the effect of lower ratio of omega-6 to omega-3 fatty acids intake (N-6/N-3) remains unknown. Previous studies of the Agricultural Health Study (AHS) reported a significant positive association between PCa and selected organophosphate pesticides (OPs) including terbufos and fonofos. OBJECTIVE: The aim of this study was to evaluate the association between N-6/N-3 and PCa and any interaction between N-6/N-3 and 2 selected OPs (i.e., terbufos and fonofos) exposure. DESIGN AND PARTICIPANTS: This case-control study, nested within a prospective cohort study, was conducted on a subgroup of the AHS population (1193 PCa cases and 14,872 controls) who returned their dietary questionnaire between 1999 and 2003 MAIN OUTCOME MEASURES: PCa was coded based on the International Classification of Diseases of Oncology (ICD-O-3) definitions and obtained from the statewide cancer registries of Iowa (2003-2017) and North Carolina (2003-2014). STATISTICAL ANALYSIS: Multivariate logistic regression analysis was applied to obtain the odds ratios adjusted (aORs) for age at dietary assessment (years), race/ethnicity (white, African American, other), physical activity (hours/week), smoking (yes/no), terbufos (yes/no), fonofos (yes/no), diabetes, lycopene intake (milligrams/day), family history of PCa, and the interaction of N-6/N-3 with age, terbufos and fonofos. Pesticide exposure was assessed by self-administrated questionnaires collecting data on ever/never use of mentioned pesticides during lifetime as a yes/no variable. Assessing the P value for the interaction between pesticides and N-6/N-3, we used the continuous variable of "intensity adjusted cumulative exposure" to terbufos and fonofos. This exposure score was based on duration, intensity and frequency of exposure. We also conducted a stratified regression analysis by quartiles of age. RESULTS: Relative to the highest N-6/N-3 quartile, the lowest quartile was significantly associated with a decreased risk of PCa (aOR=0.61, 95% CI: 0.41-0.90), and quartile-specific aORs decreased toward the lowest quartile (Ptrend=<0.01). Based on the age-stratified analysis, the protective effect was only significant for the lowest quartile of N-6/N-3 among those aged between 48 and 55 years old (aORs=0.97, 95% CI, 0.45-0.55). Among those who were exposed to terbufos (ever exposure reported as yes in the self-report questionnaires), lower quartiles of N-6/N-3 were protective albeit nonsignificant (aORs: 0.86, 0.92, 0.91 in quartiles 1,2, and 3, respectively). No meaningful findings were observed for fonofos and N-6/N-3 interaction. CONCLUSION: Findings showed that lower N-6/N-3 may decrease risk of PCa among farmers. However, no significant interaction was found between selected organophosphate pesticides and N-6/N-3.


Assuntos
Inseticidas , Exposição Ocupacional , Praguicidas , Neoplasias da Próstata , Masculino , Humanos , Pessoa de Meia-Idade , Fonofos , Estudos Prospectivos , Estudos de Casos e Controles , Praguicidas/efeitos adversos , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/prevenção & controle , Compostos Organofosforados , Inquéritos e Questionários , Organofosfatos , North Carolina/epidemiologia , Iowa/epidemiologia , Exposição Ocupacional/efeitos adversos
12.
Chempluschem ; 88(7): e202300277, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37293806

RESUMO

Extension of π-system with phosphinine (phosphorine, phosphabenzene) has been of interest because of the expected higher HOMO and lower LUMO levels compared with the corresponding carbon congeners. In this paper, a π-extension process based on the 9-phosphaanthracene skeleton was demonstrated by synthesizing 12-phosphatetraphene and 9-phosphabenzo[f]tetraphene by utilizing the deaminative aromatization pathway. Starting from 3,5-bis(trifluoromethyl)aniline, we developed the dibromotriarylmethane precursors containing the 3,5-bis(trifluoromethyl)-2-bromophenyl unit, which would be slightly effective to increase the steric congestion around the fragile P=C bonds incorporated in the fused polyaromatic skeletons. The bis-trifluoromethyl 12-phosphatetraphenes have been synthesized together with the mono-trifluoromethyl derivative, and the planar 12-phosphatetraphene skeleton was confirmed. On the other hand, the CF3 -substituted 9-phosphabenzo[f]tetraphene displayed a remarkably twisted fused five ring system leading to the wavy structures incorporating phosphinine. Also, synthetic study of 5-phosphatetracene using the bis(trifluoromethyl)phenyl unit was attempted and the incomplete elimination of the amine indicated labile characters of the observed phosphorus congener of tetracene. The findings of this study would be informative for developing heavier congeners of polyaromatic hydrocarbons (PAHs) as well as the trifluromethyl effects.


Assuntos
Derivados de Benzeno , Compostos Organofosforados , Compostos Organofosforados/química , Fósforo , Compostos de Anilina
13.
Int J Mol Sci ; 24(11)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37298598

RESUMO

The review presents extensive data (from the works of the author and literature) on the structure of C- and N-chlorophosphorylated enamines and the related heterocycles obtained by multipulse multinuclear 1H, 13C, and 31P NMR spectroscopy. The use of phosphorus pentachloride as a phosphorylating agent for functional enamines enables the synthesis of various C- and N-phosphorylated products that are heterocyclized to form various promising nitrogen- and phosphorus-containing heterocyclic systems. 31P NMR spectroscopy is the most convenient, reliable and unambiguous method for the study and identification of organophosphorus compounds with different coordination numbers of the phosphorus atom, as well as for the determination of their Z- and E-isomeric forms. An alteration of the coordination number of the phosphorus atom in the phosphorylated compounds from 3 to 6 leads to a drastic screening of the 31P nucleus from about +200 to -300 ppm. The unique structural features of nitrogen-phosphorus-containing heterocyclic compounds are discussed.


Assuntos
Compostos Heterocíclicos , Fósforo , Fósforo/química , Compostos Organofosforados/química , Compostos Heterocíclicos/química , Nitrogênio , Espectroscopia de Ressonância Magnética/métodos
14.
Free Radic Biol Med ; 205: 175-187, 2023 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-37321281

RESUMO

Mitochondria-targeted coenzyme Q10 (Mito-ubiquinone, Mito-quinone mesylate, or MitoQ) was shown to be an effective antimetastatic drug in patients with triple-negative breast cancer. MitoQ, sold as a nutritional supplement, prevents breast cancer recurrence. It potently inhibited tumor growth and tumor cell proliferation in preclinical xenograft models and in vitro breast cancer cells. The proposed mechanism of action involves the inhibition of reactive oxygen species by MitoQ via a redox-cycling mechanism between the oxidized form, MitoQ, and the fully reduced form, MitoQH2 (also called Mito-ubiquinol). To fully corroborate this antioxidant mechanism, we substituted the hydroquinone group (-OH) with the methoxy group (-OCH3). Unlike MitoQ, the modified form, dimethoxy MitoQ (DM-MitoQ), lacks redox-cycling between the quinone and hydroquinone forms. DM-MitoQ was not converted to MitoQ in MDA-MB-231 cells. We tested the antiproliferative effects of both MitoQ and DM-MitoQ in human breast cancer (MDA-MB-231), brain-homing cancer (MDA-MB-231BR), and glioma (U87MG) cells. Surprisingly, DM-MitoQ was slightly more potent than MitoQ (IC50 = 0.26 µM versus 0.38 µM) at inhibiting proliferation of these cells. Both MitoQ and DM-MitoQ potently inhibited mitochondrial complex I-dependent oxygen consumption (IC50 = 0.52 µM and 0.17 µM, respectively). This study also suggests that DM-MitoQ, which is a more hydrophobic analog of MitoQ (logP: 10.1 and 8.7) devoid of antioxidant function and reactive oxygen species scavenging ability, can inhibit cancer cell proliferation. We conclude that inhibition of mitochondrial oxidative phosphorylation by MitoQ is responsible for inhibition of breast cancer and glioma proliferation and metastasis. Blunting the antioxidant effect using the redox-crippled DM-MitoQ can serve as a useful negative control in corroborating the involvement of free radical-mediated processes (e.g., ferroptosis, protein oxidation/nitration) using MitoQ in other oxidative pathologies.


Assuntos
Neoplasias da Mama , Glioma , Humanos , Feminino , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Hidroquinonas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Neoplasias da Mama/tratamento farmacológico , Ubiquinona/farmacologia , Oxirredução , Proliferação de Células , Estresse Oxidativo , Compostos Organofosforados/farmacologia
15.
Chem Biol Interact ; 376: 110460, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36963650

RESUMO

The acute effects of exposure to organophosphorus toxicants are explained by inhibition of acetylcholinesterase activity. However, the mechanisms that explain long term illness associated with organophosphorus exposure are still under investigation. We find that organophosphorus nerve agents and organophosphorus pesticides make covalent adducts not only on the serine from acetylcholinesterase, but also on tyrosine, lysine, glutamate, serine and threonine from a variety of proteins. Almost any protein can be modified by a high dose of organophosphorus toxicant. A low dose of 10 µM chlorpyrifos oxon added to the serum-free culture medium of human neuroblastoma SH-SY5Y cells resulted in tyrosine adducts on 48 proteins immunopurified from the cell lysate. We identified the adducted proteins by mass spectrometry after immunopurifying modified proteins with a rabbit anti-diethoxyphospho-tyrosine monoclonal antibody which biased this study for tyrosine adducts. In cultured cells, the primary organophosphate targets are abundant proteins. Organophosphate-modified proteins may disrupt physiological processes. In separate experiments we identified organophosphate adducts on lysine. Organophosphylation activates the lysine for protein crosslinking. The activated lysine reacts with glutamic acid or aspartic acid protein side chains to form an isopeptide bond between proteins, resulting in high molecular weight crosslinked proteins. Crosslinked proteins form insoluble aggregates that may lead to neurogenerative disease.


Assuntos
Neuroblastoma , Praguicidas , Animais , Humanos , Coelhos , Acetilcolinesterase/metabolismo , Lisina/química , Compostos Organofosforados/metabolismo , Peso Molecular , Proteínas/química , Tirosina/metabolismo , Ácido Glutâmico/química
16.
Food Chem Toxicol ; 175: 113747, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36997054

RESUMO

This research aimed to explore the protective effect of quercetin against nephrotoxicity induced by four organophosphate pesticide mixtures (PM) using untargeted metabolomics technology in rat kidneys. Sixty male Wistar rats were randomly divided into six groups: control, low-dose quercetin treated (10 mg/kg bw), high-dose quercetin treated (50 mg/kg bw), PM-treated, and two dosages of quercetin + PM-treated. Metabolomics results showed that 17 differential metabolites were identified in the PM-treated group, and pathway analysis revealed that renal metabolic disorders include purine metabolism, glycerophospholipid metabolism, and vitamin B6 metabolism. When high-dose quercetin and PM-treated were administered to rats concurrently, the intensities of differential metabolites were substantially restored (p < 0.01), suggesting that quercetin can improve renal metabolic disorders caused by organophosphate pesticides (OPs). Mechanistically, quercetin could regulate the purine metabolism disorder and endoplasmic reticulum stress (ERS)-mediated autophagy induced by OPs by inhibiting XOD activity. Moreover, quercetin inhibits PLA2 activity to regulate glycerophospholipid metabolism and it could also exert antioxidant and anti-inflammatory effects to correct vitamin B6 metabolism in rat kidneys. Taken together, the high dose of quercetin (50 mg/kg. bw) has a certain protective effect on OPs-induced nephrotoxicity in rats, which provides a theoretical basis for quercetin against nephrotoxicity caused by OPs.


Assuntos
Inseticidas , Nefropatias , Praguicidas , Ratos , Masculino , Animais , Quercetina/farmacologia , Quercetina/uso terapêutico , Praguicidas/efeitos adversos , Compostos Organofosforados , Ratos Wistar , Antioxidantes/farmacologia , Metabolômica , Nefropatias/induzido quimicamente , Nefropatias/prevenção & controle , Nefropatias/tratamento farmacológico , Inseticidas/farmacologia , Estresse Oxidativo , Organofosfatos/efeitos adversos , Glicerofosfolipídeos/farmacologia , Glicerofosfolipídeos/uso terapêutico , Vitamina B 6/farmacologia , Purinas
17.
PLoS One ; 18(3): e0283181, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36996021

RESUMO

The ability of the cyclodextrin-oxime construct 6-OxP-CD to bind and degrade the nerve agents Cyclosarin (GF), Soman (GD) and S-[2-[Di(propan-2-yl)amino]ethyl] O-ethyl methylphosphonothioate (VX) has been studied using 31P-nuclear magnetic resonance (NMR) under physiological conditions. While 6-OxP-CD was found to degrade GF instantaneously under these conditions, it was found to form an inclusion complex with GD and significantly improve its degradation (t1/2 ~ 2 hrs) relative over background (t1/2 ~ 22 hrs). Consequently, effective formation of the 6-OxP-CD:GD inclusion complex results in the immediate neutralization of GD and thus preventing it from inhibiting its biological target. In contrast, NMR experiments did not find evidence for an inclusion complex between 6-OxP-CD and VX, and the agent's degradation profile was identical to that of background degradation (t1/2 ~ 24 hrs). As a complement to this experimental work, molecular dynamics (MD) simulations coupled with Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) calculations have been applied to the study of inclusion complexes between 6-OxP-CD and the three nerve agents. These studies provide data that informs the understanding of the different degradative interactions exhibited by 6-OxP-CD with each nerve agent as it is introduced in the CD cavity in two different orientations (up and down). For its complex with GF, it was found that the oxime in 6-OxP-CD lies in very close proximity (PGF⋯OOxime ~ 4-5 Å) to the phosphorus center of GF in the 'downGF' orientation for most of the simulation accurately describing the ability of 6-OxP-CD to degrade this nerve agent rapidly and efficiently. Further computational studies involving the center of masses (COMs) for both components (GF and 6-OxP-CD) also provided some insight on the nature of this inclusion complex. Distances between the COMs (ΔCOM) lie closer in space in the 'downGF' orientation than in the 'upGF' orientation; a correlation that seems to hold true not only for GF but also for its congener, GD. In the case of GD, calculations for the 'downGD' orientation showed that the oxime functional group in 6-OxP-CD although lying in close proximity (PGD⋯OOxime ~ 4-5 Å) to the phosphorus center of the nerve agent for most of the simulation, adopts another stable conformation that increase this distance to ~ 12-14 Å, thus explaining the ability of 6-OxP-CD to bind and degrade GD but with less efficiency as observed experimentally (t1/2 ~ 4 hr. vs. immediate). Lastly, studies on the VX:6-OxP-CD system demonstrated that VX does not form a stable inclusion complex with the oxime-bearing cyclodextrin and as such does not interact in a way that is conducive to an accelerated degradation scenario. Collectively, these studies serve as a basic platform from which the development of new cyclodextrin scaffolds based on 6-OxP-CD can be designed in the development of medical countermeasures against these highly toxic chemical warfare agents.


Assuntos
Substâncias para a Guerra Química , Ciclodextrinas , Contramedidas Médicas , Agentes Neurotóxicos , Soman , Oximas , Simulação de Dinâmica Molecular , Compostos Organofosforados/química , Fósforo
18.
Epilepsia Open ; 8 Suppl 1: S117-S140, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36807554

RESUMO

Despite new antiseizure medications, the development of cholinergic-induced refractory status epilepticus (RSE) continues to be a therapeutic challenge as pharmacoresistance to benzodiazepines and other antiseizure medications quickly develops. Studies conducted by Epilepsia. 2005;46:142 demonstrated that the initiation and maintenance of cholinergic-induced RSE are associated with trafficking and inactivation of gamma-aminobutyric acid A receptors (GABAA R) thought to contribute to the development of benzodiazepine pharmacoresistance. In addition, Dr. Wasterlain's laboratory reported that increased N-methyl-d-aspartate receptors (NMDAR) and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPAR) contribute to enhanced glutamatergic excitation (Neurobiol Dis. 2013;54:225; Epilepsia. 2013;54:78). Thus, Dr. Wasterlain postulated that targeting both maladaptive responses of reduced inhibition and increased excitation that is associated with cholinergic-induced RSE should improve therapeutic outcome. We currently review studies in several animal models of cholinergic-induced RSE that demonstrate that benzodiazepine monotherapy has reduced efficacy when treatment is delayed and that polytherapy with drugs that include a benzodiazepine (eg midazolam and diazepam) to counter loss of inhibition, concurrent with an NMDA antagonist (eg ketamine) to reduce excitation provide improved efficacy. Improved efficacy with polytherapy against cholinergic-induced seizure is demonstrated by reduction in (1) seizure severity, (2) epileptogenesis, and (3) neurodegeneration compared with monotherapy. Animal models reviewed include pilocarpine-induced seizure in rats, organophosphorus nerve agent (OPNA)-induced seizure in rats, and OPNA-induced seizure in two mouse models: (1) carboxylesterase knockout (Es1-/- ) mice which, similarly to humans, lack plasma carboxylesterase and (2) human acetylcholinesterase knock-in carboxylesterase knockout (KIKO) mice. We also review studies showing that supplementing midazolam and ketamine with a third antiseizure medication (valproate or phenobarbital) that targets a nonbenzodiazepine site rapidly terminates RSE and provides further protection against cholinergic-induced SE. Finally, we review studies on the benefits of simultaneous compared with sequential drug treatments and the clinical implications that lead us to predict improved efficacy of early combination drug therapies. The data generated from seminal rodent studies of efficacious treatment of cholinergic-induced RSE conducted under Dr. Wasterlain's guidance suggest that future clinical trials should treat the inadequate inhibition and temper the excess excitation that characterize RSE and that early combination therapies may provide improved outcome over benzodiazepine monotherapy.


Assuntos
Ketamina , Agentes Neurotóxicos , Estado Epiléptico , Ratos , Camundongos , Humanos , Animais , Midazolam/efeitos adversos , Anticonvulsivantes/uso terapêutico , Agentes Neurotóxicos/efeitos adversos , Ketamina/farmacologia , Ketamina/uso terapêutico , Acetilcolinesterase/uso terapêutico , Compostos Organofosforados/efeitos adversos , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/tratamento farmacológico , Convulsões/tratamento farmacológico , Benzodiazepinas/efeitos adversos , Colinérgicos/efeitos adversos , Receptores de Glutamato/uso terapêutico , Ácido gama-Aminobutírico/efeitos adversos
19.
Food Chem ; 412: 135546, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-36716625

RESUMO

The abuse of organophosphorus pesticides (OPPs) in tea planting makes it easy to transfer from tea into its infusion, bringing potential health risks to consumers. Thus, it is essential to adopt reliable techniques to remove OPPs from tea infusion. In this study, three treatment methods were used to modify carbonized bacterial cellulose (CBC) to improve its adsorption performance. Among them, CBC treated by hydrazine hydrate (N-CBC) had the best adsorption effect, whose removal rate for dicrotophos is 13 times that of CBC. The in-depth study of adsorption mechanism proved that hydrophobic interaction dominated the adsorption of OPPs onto N-CBC. The pseudo-second-order kinetic model and Langmuir isotherm model were more suitable to describe the process. Additionally, there were no significant changes in tea infusion quality after N-CBC treatment. This work clarifies that N-CBC benefitted from simple preparation method, excellent adsorption performance and unique adsorption mechanism has potential applications in tea infusion.


Assuntos
Praguicidas , Poluentes Químicos da Água , Compostos Organofosforados/análise , Chá/química , Adsorção , Celulose , Cinética , Poluentes Químicos da Água/química
20.
J AOAC Int ; 106(5): 1209-1219, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36622007

RESUMO

BACKGROUND: The presence of undesirable substances, including pesticides (xenobiotics) in betel leaf (Piper betel), is a great concern for consumers because it is chewed and consumed directly. To protect the consumer's health, a modified QuEChERS method for monitoring purposes and subsequent decontamination process has been developed. OBJECTIVE: The goal of this work was to establish a multi-residue analytical method for monitoring nonpermitted organophosphorus pesticide residues in betel leaf, as well as cost-effective cleaning strategies. METHOD: The homogenized 15 g samples (20 betel leaf samples collected in West Bengal, India) were extracted with a modified QuEChERS method using acetonitrile, reconstituted to acetone, and finally analyzed by GC-MS/MS. Possible decontamination techniques (such as tap water washing, 2% saltwater washing, and lukewarm water washing) were evaluated. RESULTS: The limit of detection ranged from 0.003 to 0.005 mg/kg, and limit of quantification was 0.01 mg/kg. Recoveries ranged from 80 to 120% with RSDr 9%. One sample was found to contain three pesticides 4 to 7 times higher than MRLs. Suggested decontamination methods allowed reducing toxic traces below European limits. CONCLUSIONS: The suggested approach is useful for determining pesticide residues in betel leaves quickly. Traditional techniques of processing betel leaves may reduce pesticide residues below regulatory limits. HIGHLIGHTS: A multi-residue method and decontamination of pesticides in betel leaf using QuEChERS-GC-MS/MS technology with satisfactory method performance was achieved. Domestic decontamination techniques have a high efficacy in reducing pesticide residues from betel leaves, making them safe for human consumption.


Assuntos
Resíduos de Praguicidas , Praguicidas , Humanos , Espectrometria de Massas em Tandem/métodos , Resíduos de Praguicidas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Praguicidas/análise , Descontaminação , Compostos Organofosforados/análise , Saúde Pública , Tecnologia , Água/análise , Folhas de Planta/química
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