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1.
Int J Mol Sci ; 25(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38891887

RESUMO

With projections suggesting an increase in the global use of neonicotinoids, contemporary farmers can get caught on the "pesticide treadmill", thus creating ecosystem side effects. The aim of this study was to investigate the sorption/desorption behavior of acetamiprid, imidacloprid, and thiacloprid that controls their availability to other fate-determining processes and thus could be useful in leveling the risk these insecticides or their structural analogues pose to the environment, animals, and human health. Sorption/desorption isotherms in four soils with different organic matter (OC) content were modelled by nonlinear equilibrium models: Freundlich's, Langmuir's, and Temkin's. Sorption/desorption parameters obtained by Freundlich's model were correlated to soil physico-chemical characteristics. Even though the OC content had the dominant role in the sorption of the three insecticides, the role of its nature as well as the chemical structure of neonicotinoids cannot be discarded. Insecticides sorbed in the glassy OC phase will be poorly available unlike those in the rubbery regions. Imidacloprid will fill the sorption sites equally in the rubbery and glassy phases irrespective of its concentration. The sorption of thiacloprid at low concentrations and acetamiprid at high concentrations is controlled by hydrophilic aromatic structures, "trapping" the insecticides in the pores of the glassy phase of OC.


Assuntos
Inseticidas , Neonicotinoides , Nitrocompostos , Tiazinas , Neonicotinoides/química , Inseticidas/química , Nitrocompostos/química , Tiazinas/química , Adsorção , Solo/química , Poluentes do Solo/química , Piridinas/química , Imidazóis/química
2.
Chemosphere ; 273: 128563, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33070975

RESUMO

Dimethoate is an organophosphorus insecticide still used in Croatia and worldwide, with polar structure and high water solubility that make it prone to leaching. This study analyzed how physico-chemical properties of soils affected dimethoate sorption and mobility. For that purpose, five soil samples were collected from three Croatian regions (two coastal and one mountain region). Dimethoate sorption process was analyzed using the batch procedure while its mobility and leaching potential was investigated by column experiment. The results showed that dimethoate sorption can be adequately described by Freundlich model. All isotherms were of L-type with varying degrees of non-linearity, indicating different sorption efficiencies and distribution of sorption sites energies among the soils. Energy distribution was broader in soils richer in organic matter (OM). KF values indicated relatively low sorption efficiency for all soils, with an increase of KF values proportional to OM content. Mechanisms involved in dimethoate sorption and mobility were analyzed by fitting the breakthrough curves (BTCs) with two mathematical models, namely one-site equilibrium (ELM) and two-site nonequilibrium sorption model (NELM). Correlations were quantified by Kendall-Tau test, which revealed the strongest correlation of KF value with OM content, cation exchange capacity and the humic acid content, while correlations with pH, clay content and A465nm/A665nm ratio were negative and insignificant. Based on these findings, a model for prediction of leaching potential was formed. A simplified model for dimethoate sorption/transport was proposed.


Assuntos
Inseticidas , Poluentes do Solo , Adsorção , Croácia , Dimetoato , Solo , Poluentes do Solo/análise
3.
Food Chem Toxicol ; 142: 111472, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32504734

RESUMO

Aucubin is pharmacologically active natural compound which possesses numerous beneficial properties. This study aimed to evaluate the protective effect of aucubin against cisplatin (CP)-induced acute kidney injury in mice and the mechanism of its action. Aucubin was administrated to mice orally or intraperitoneally (ip) (1.5 and 5 mg/kg) for two consecutive days, two days after ip injection of cisplatin (CP), 11 mg/kg. Treatment with aucubin by both routes of administration ameliorated histopathological changes and reduced elevated serum markers of kidney injury. CP administration increased renal expression of heme oxygenase-1 (HO-1) and 4-hydroxynonenal (4-HNE), as well as tumor necrosis factor-alpha (TNF-α), which was dose-dependently ameliorated by aucubin. Moreover, aucubin reduced increased renal expression of cleaved caspase-3 and -9 and decreased poly (ADP-ribose) polymerase (PARP) cleavage. Mechanistically, aucubin suppressed the activation of several signaling pathways involved in inflammation and apoptosis, including nuclear factor-kappa B (NF-κB), signal transducer and activator of transcription 3 (STAT3), Akt, extracellular signal-regulated kinase 1/2 (ERK1/2) and forkhead box O3a (FOXO3a). Parenteral application was marginally but statistically more effective in reducing CP-induced kidney injury than oral administration. The findings of this study suggest that aucubin acts as a protective agent against CP-induced nephrotoxicity, which should be further investigated.


Assuntos
Injúria Renal Aguda/prevenção & controle , Antineoplásicos/toxicidade , Cisplatino/toxicidade , Glucosídeos Iridoides/farmacologia , Injúria Renal Aguda/induzido quimicamente , Administração Oral , Animais , Proteína Forkhead Box O3/antagonistas & inibidores , Infusões Parenterais , Glucosídeos Iridoides/administração & dosagem , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo
4.
Neurotoxicology ; 57: 1-12, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27570231

RESUMO

To analyze iron- and gender-dependent mechanisms possibly involved in pathogenesis of multiple sclerosis (MS) in this study we evaluated the effects of iron overload (IO) on iron status and lipid peroxidation processes (LPO) in tissues of female and male DA rats during chronic relapsing experimental autoimmune encephalomyelitis, a well-established MS animal model. Rats were treated by iron sucrose (75mg/kg bw/day) or with saline solution during two weeks before the sensitization with bovine brain homogenate in complete Freund's adjuvant. Clinical signs of EAE were monitored during 29 days. Serum and tissues of CNS and liver were sampled before immunization and at day 13th post immunization (during acute phase of EAE). The determination of ferritin, iron, malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) and evaluation of histopathology were performed by ELISA, ICP spectrometry and immunohistochemistry. Results showed that IO in female EAE rats accelerated the onset of disease. In contrast, in male rats it accelerated the progression of disease and increased the mortality rate. During acute phase of EAE female IO rats sequestered more Fe in the liver, spinal cord and in the brain and produced more ferritin than male EAE rats. Male rats, however, reacted on IO by higher production of MDA or 4-HNE in the neural tissues and showed greater signs of plaque formation and gliosis in spinal cord. The data point to sexual dimorphism in mechanisms that regulate peripheral and brain iron homeostasis and imply that men and women during MS might be differentially vulnerable to exogenous iron overload.


Assuntos
Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/fisiopatologia , Homeostase/imunologia , Sobrecarga de Ferro/complicações , Ferro/metabolismo , Peroxidação de Lipídeos/imunologia , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/mortalidade , Feminino , Ferritinas/sangue , Adjuvante de Freund/imunologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Masculino , Ratos , Medula Espinal/metabolismo
5.
Oxid Med Cell Longev ; 2016: 9191407, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26925195

RESUMO

Polyphenols can act as oxidants in some conditions, inducing redox-sensitive genes. We investigated the effect of preexposure to the olive oil polyphenols extract (PFE) on time-dependent changes in the hepatic oxidative state in a model of liver regeneration-a process in which oxidative stress associated with the metabolic overload accounts for the early events that contribute to the onset of liver self-repair. Liver regeneration was induced by one-third hepatectomy in mice. Prior to hepatectomy, mice were intraperitoneally given either PFE (50 mg/kg body weight) or saline for seven consecutive days, while respective controls received vehicle alone. Redox state-regulating enzymes and thiol proteins along with the mRNA levels of Nrf2 gene and its targets γ-glutamylcysteine synthetase and heme oxygenase-1 were determined at different time intervals after hepatectomy. The liver mass restoration was calculated to assess hepatic regeneration. The resulting data demonstrate the effectiveness of preexposure to PFE in stimulating liver regeneration in a model of a small tissue loss which may be ascribed to the transient increase in oxidant load during the first hours after hepatectomy and associated induction of stress response gene-profiles under the control of Nrf2.


Assuntos
Hepatectomia , Fígado/patologia , Azeite de Oliva/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Estresse Fisiológico/genética , Animais , Antioxidantes/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Glutationa Transferase/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/cirurgia , Masculino , Camundongos Endogâmicos C57BL , Especificidade de Órgãos/efeitos dos fármacos , Especificidade de Órgãos/genética , Reação em Cadeia da Polimerase em Tempo Real , Estresse Fisiológico/efeitos dos fármacos , Compostos de Sulfidrila/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
6.
Pharmacol Res ; 87: 160-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24880136

RESUMO

Infectious mastitis is a common condition among lactating women, with staphylococci and streptococci being the main aetiological agents. In this context, some lactobacilli strains isolated from breast milk appear to be particularly effective for treating mastitis and, therefore, constitute an attractive alternative to antibiotherapy. A (1)H NMR-based metabolomic approach was applied to detect metabolomic differences after consuming a probiotic strain (Lactobacillus salivarius PS2) in women with mastitis. 24h urine of women with lactational mastitis was collected at baseline and after 21 days of probiotic (PB) administration. Multivariate analysis (OSC-PLS-DA and hierarchical clustering) showed metabolome differences after PB treatment. The discriminant metabolites detected at baseline were lactose, and ibuprofen and acetaminophen (two pharmacological drugs commonly used for mastitis pain), while, after PB intake, creatine and the gut microbial co-metabolites hippurate and TMAO were detected. In addition, a voluntary desertion of the pharmacological drugs ibuprofen and acetaminophen was observed after probiotic administration. The application of NMR-based metabolomics enabled the identification of the overall effects of probiotic consumption among women suffering from mastitis and highlighted the potential of this approach in evaluating the outcomes of probiotics consumption. To our knowledge, this is the first time that this approach has been applied in women with mastitis during lactation.


Assuntos
Lactação/urina , Lactobacillus , Mastite/urina , Probióticos/uso terapêutico , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Metabolômica , Probióticos/farmacologia
7.
Histol Histopathol ; 29(3): 407-16, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24068621

RESUMO

To investigate the effects of air pollution related with the gasoline/petrochemical industry the expression of metallothionein I (MT-I) mRNA and tissue metals were analyzed in organs of mice, exposed to gasoline (G) vapor in laboratory conditions. Control groups consisted of intact mice and of those exposed in the metabolic chamber to fresh air. The data obtained by RT-PCR and inductively coupled plasma spectrometry have shown that exposure to G vapor leads to upregulation of MT-I mRNA in organs that receive a strong respiratory and olfactory input or participate in gasoline degradation and elimination (lungs, brain, kidney and liver). Besides, in the brain and in the lungs, kidney and liver a decreased tissue content of Zn²âº or Cu²âº and Mg²âº was found (p<0.001). Some of these changes were obtained also in mice closed in the metabolic chamber, pointing to the involvement of stress-induced mechanisms in the transcriptional regulation of MTs.


Assuntos
Poluição do Ar/efeitos adversos , Gasolina/efeitos adversos , Metalotioneína/biossíntese , Animais , Química Encefálica , Cobre/análise , Rim/química , Rim/patologia , Fígado/química , Fígado/patologia , Pulmão/química , Pulmão/patologia , Magnésio/análise , Metalotioneína/análise , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrofotometria Atômica , Zinco/análise
8.
Biol Trace Elem Res ; 143(1): 332-43, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20845085

RESUMO

To elucidate the role of iron in the pathomechanisms of autoimmune CNS disorders, we estimated the tissue concentrations of Fe(2+) in the brain, spinal cord, and liver in the chronic relapsing form of experimental autoimmune encephalomyelitis (EAE). The disease was induced in Dark Agouti (DA) strain of rats, by subcutaneous injection of bovine brain homogenate in complete Freund's adjuvant (CFA). Control rats consisted of unsensitized rats and of rats treated with CFA or saline. The data obtained by clinical assessment and by inductively coupled plasma spectrometry have shown that the attacks of disease (on the 12th and 22nd post-immunization day) were followed by high accumulation of iron in the liver. Additionally, during the second attack of disease, the decreased concentration of Fe(2+) was found in cervical spinal cord. The data point to regulatory effects of iron and hepatic trace elements regulating mechanisms in the pathogenesis of EAE.


Assuntos
Encefalomielite Autoimune Experimental/metabolismo , Ferro/metabolismo , Animais , Encéfalo/metabolismo , Fígado/metabolismo , Masculino , Ratos , Medula Espinal/metabolismo
9.
Biol Trace Elem Res ; 114(1-3): 249-68, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17206007

RESUMO

To better elucidate previous results showing that partial hepatectomy noticeably changes the tissue content of zinc, calcium, magnesium, and iron(II) ions in regenerating the liver, thymus, and spleen, we report on the correlation of these metal tissue kinetics in these organs with the expression of metallothionein-I+II (MT-I+II) proteins and MT-I mRNA in early postoperative period (1, 2, 6, 12, and 24 h) after one-third hepatectomy (pHx). The results showed that 2 h after pHx the regenerating liver accumulated Zn2+, Ca2+, Mg2+, and Fe2+ ions while decreasing the concentration of all these metals in the spleen and of Zn2+ in the thymus. On the 24th h, a new high accumulation of Zn2+ and Ca2+ was seen in the regenerating liver and of Zn2+, Ca2+, and Fe2+ in the spleen. Simultaneously, MT-I mRNA increased in the liver and spleen. In hepatocytes and on several spleen and thymus mononuclear lymphatic cells, the increased expression of MT proteins was found mainly in the cytoplasm and nuclei. The areas expressing MTs in regenerating liver inversely correlated with those containing apoptotic cells, suggesting that these proteins participate in tissue restoration through reduction or increase of metal ions after injury to the liver.


Assuntos
Hepatectomia , Metalotioneína/metabolismo , Metais/farmacocinética , Animais , Sequência de Bases , Cálcio/metabolismo , Primers do DNA , Compostos Ferrosos/metabolismo , Marcação In Situ das Extremidades Cortadas , Fígado/metabolismo , Magnésio/metabolismo , Metalotioneína/genética , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Baço/metabolismo , Timo/metabolismo , Distribuição Tecidual , Zinco/metabolismo
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