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1.
Environ Toxicol Pharmacol ; 104: 104283, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37775076

RESUMO

Retained lead fragments from nonfatal firearm injuries pose a risk of lead poisoning. While chelation is well-established as a lead poisoning treatment, it remains unclear whether chelation mobilizes lead from embedded lead fragments. Here, we tested whether 1) DMSA/succimer or CaNa2EDTA increases mobilization of lead from fragments in vitro, and 2) succimer is efficacious in chelating fragment lead in vivo, using stable lead isotope tracer methods in a rodent model of embedded fragments. DMSA was > 10-times more effective than CaNa2EDTA in mobilizing fragment lead in vitro. In the rodent model, succimer chelation on day 1 produced the greatest blood lead reductions, and fragment lead was not mobilized into blood. However, with continued chelation and over 3-weeks post-chelation, blood lead levels rebounded with mobilization of lead from the fragments. These findings suggest prolonged chelation will increase fragment lead mobilization post-chelation, supporting the need for long-term surveillance in patients with retained fragments.


Assuntos
Armas de Fogo , Intoxicação por Chumbo , Ferimentos por Arma de Fogo , Animais , Humanos , Succímero , Chumbo/toxicidade , Ácido Edético/farmacologia , Ácido Edético/uso terapêutico , Roedores , Quelantes/farmacologia , Quelantes/uso terapêutico , Intoxicação por Chumbo/tratamento farmacológico , Intoxicação por Chumbo/metabolismo
2.
Bioengineered ; 13(4): 11156-11168, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35485286

RESUMO

Environmental lead contamination can cause chronic renal disease with a common clinical manifestation of renal fibrosis and constitutes a major global public health threat. Aberrant proliferation and extracellular matrix (ECM) accumulation in renal interstitial fibroblasts are key pathological causes of renal fibrosis. However, the mechanism underlying lead-induced kidney fibrosis remains unclear. The present study analyzed gene expression prolifes in lead acetate-treated primary mice renal interstitial fibroblasts and confirmed the aberrant expression of CC chemokine ligand (CCL) 20, one of the most obvious up-regulated genes. Analogously, lead acetate exposure dose-dependently increased CCL20 transcription, protein expression and release. Knockdown of CCL20 suppressed lead acetate-induced fibroblast proliferation, hydroxyproline contents, transforming growth factor-beta production and ECM-related protein (Collagen I and fibronectin) expression. Bioinformatics analysis predicted five top miRNAs targeting CCL20. Among them, miR-143-5p expression was dose-dependently decreased in lead acetate-treated fibroblasts. Mechanistically, miR-143-5p directly targeted CCL20. Elevation of miR-143-5p antagonized lead acetate-induced fibroblast proliferation, hydroxyproline and ECM-related protein expression, which were reversed by CCL20 overexpression. Additionally, CCL20 knockdown suppressed lead acetate-mediated Smad2/3 and AKT pathway activation. Notably, miR-143-5p overexpression attenuated the activation of the Smad2/3 and AKT pathway in lead acetate-exposed fibroblasts, which was counteracted by CCL20 elevation. miR-143-5p injection ameliorated renal fibrosis progression in mice in vivo. Thus, targeting CCL20 by miR-143-5p could alleviate renal fibrosis progression by regulating fibroblast proliferation and ECM deposition via the Smad2/3 and AKT signaling, providing a potential therapeutic target for environmental lead contamination-evoked fibrotic kidney disease.


Assuntos
Nefropatias , Intoxicação por Chumbo , MicroRNAs , Animais , Proliferação de Células/genética , Quimiocinas CC/metabolismo , Feminino , Fibroblastos/metabolismo , Fibrose , Humanos , Hidroxiprolina/metabolismo , Nefropatias/metabolismo , Intoxicação por Chumbo/metabolismo , Intoxicação por Chumbo/patologia , Ligantes , Masculino , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
4.
Toxicology ; 457: 152810, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33984407

RESUMO

With the rapid development of economic globalization and industrialization, lead (Pb), one of the most important heavy metals, has been used widely since antiquity for several purposes. In fact, its impact on the health of animals and humans is a significant public health risk all the time. Pb could be accumulated in the body for a long time, causing irreversible damage to the health of animals and humans, including hostile reproductive health. Up to now, although there are some published studies on impeding the normal development of ovarian folliculogenesis of female resulted from Pb exposure, with the damage of structure in uterine tissue, the imbalance of female menstrual status, and the change of hormone levels. The potential mechanism of Pb exposure on female reproduction system, however, remains enigmatic. How to alleviate the damage of Pb toxicity to reproductive function of female has become an urgent problem. Therefore, the aim of the present review is to discuss the information on the growth and development of ovarian follicle of mammalians and the potential toxic mechanism when exposed to Pb. The literatures were collected via various websites and consulting books, reports, etc. In summary, Pb impair folliculogenesis of mammalians, which may be related to the interference to the hypothalamic-pituitary-gonadal (HPG) axis and the production of reactive oxygen species (ROS), in turn impairs various molecules including proteins, lipids and DNA, as well as the disruption of the antioxidant defense system, ionic equilibrium and endoplasmic reticulum homeostasis.


Assuntos
Intoxicação por Chumbo/metabolismo , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Estresse Oxidativo/efeitos dos fármacos , Animais , Feminino , Humanos , Folículo Ovariano/metabolismo , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Reprodução/efeitos dos fármacos , Reprodução/fisiologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-33278595

RESUMO

Saikosaponin a (SSa), a triterpene saponin extracted from Bupleurumfalcatum L., has been reported to have anti-inflammatory activity. In the present study, we investigated the effects of SSa on lead-induced kidney injury in common carp. Kidney histological changes were detected by H&E staining. The levels of TNF-α, IL-1ß, MPO, MDA, GSH, and SOD activity were also measured. Furthermore, the NF-κB and Nrf2 signaling pathways were tested by western blot analysis. The results showed that lead-induced kidney histological change was attenuated by SSa. Lead-induced TNF-α, IL-1ß, MPO, and MDA production were also suppressed by SSa. Meanwhile, lead could decrease GSH level and SOD activity and the decreases were inhibited by SSa. Furthermore, we found SSa significantly inhibited lead-induced NF-κB translocation. In addition, the expression of Nrf2 and HO-1 were increased by the treatment of SSa and Keap1 expression was decreased by SSa. In conclusion, this study indicated that SSa inhibited lead-induced kidney injury in carp through suppressing inflammatory and oxidative responses, and the mechanism may be involved in the inhibition of NF-κB and activation of Nrf2 signaling pathway.


Assuntos
Injúria Renal Aguda/veterinária , Carpas , Doenças dos Peixes/tratamento farmacológico , Proteínas de Peixes/metabolismo , Intoxicação por Chumbo/veterinária , Chumbo/toxicidade , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Ácido Oleanólico/análogos & derivados , Estresse Oxidativo , Saponinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Doenças dos Peixes/induzido quimicamente , Doenças dos Peixes/metabolismo , Intoxicação por Chumbo/tratamento farmacológico , Intoxicação por Chumbo/metabolismo , Ácido Oleanólico/farmacologia , Distribuição Aleatória
6.
J Trace Elem Med Biol ; 64: 126702, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33285442

RESUMO

BACKGROUND: Interaction between metals is known from earlier studies, in which one metal influences the absorption and functional role of other. Lead is known to cause debilitating effects in living organisms and also prevents several essential trace metals from functioning normally. METHODS: The relevant literature using the key words lead toxicity, lead zinc interaction, zinc nutrition and the ability of zinc to act against lead has been reviewed. RESULTS: Role of several nutrients in reducing the manifestations of toxic metals have been elucidated recently. Lead damages bio-membranes, causes cognitive disabilities and disturbs the normal process of DNA replication and transcription. Zinc on the other hand helps in proper maintenance of the cellular membranes and plays an important role as a metal cofactor in most of the proteins vital for membrane integrity. Zinc has essential role in cognitive functioning, zinc finger proteins and significantly neutralizes most toxic effects of lead. CONCLUSION: Increased lead exposure and limited resources for tackling lead poisoning may cause an increased possibility of future environmental emergencies. Interactions between essential nutrient metals and non-essential toxic metals may act as important factor which can be used to target the metal toxicities. An assumption is made that the lead toxicity can be reduced by maintaining the status of essential trace metals like zinc.


Assuntos
Intoxicação por Chumbo/metabolismo , Chumbo/metabolismo , Zinco/metabolismo , Animais , Humanos , Chumbo/toxicidade , Zinco/toxicidade
7.
Toxicol Lett ; 335: 11-27, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32949623

RESUMO

Lead is a toxin of great public health concern affecting the young and aging population. Several factors such as age, gender, lifestyle, dose, and genetic makeup result in interindividual variations to lead toxicity mainly due to variations in metabolic consequences. Hence, the present study aimed to examine dose-dependent lead-induced systemic changes in metabolism using rat model by administering specific doses of lead such as 10 (low lead; L-Pb), 50 (moderate lead; M-Pb), and 100 mg/kg (high lead; H-Pb) body weight for a period of one month. Biochemical and haematological analysis revealed that H-Pb was associated with low body weight and feed efficiency, low total protein levels (p ≤ 0.05), high blood lead (Pb-B) levels (p ≤ 0.001), low ALAD (δ-aminolevulinate dehydratase) activity (p ≤ 0.0001), high creatinine (p ≤ 0.0001) and blood urea nitrogen (BUN) (p ≤ 0.01) levels, elevated RBC and WBC counts, reduced haemoglobin and blood cell indices compared to control. Spatial learning and memory test revealed that H-Pb exposed animals presented high latency to the target quadrant and escape platform compared to other groups indicating H-Pb alters cognition function in rats. Histopathological changes were observed in liver and kidney as they are the main target organs of lead toxicity. LC-MS analysis further revealed that Butyryl-L-carnitine (p ≤ 0.01) and Ganglioside GD2 (d18:0/20:0) (p ≤ 0.05) levels were significantly reduced in H-Pb group compared to all groups. Further, pathway enrichment analysis revealed abundance and significantly modulated metabolites associated with oxidative stress pathways. The present study is the first in vivo model of dose-dependent lead exposure for serum metabolite profiling.


Assuntos
Rim/efeitos dos fármacos , Intoxicação por Chumbo/metabolismo , Chumbo/toxicidade , Fígado/efeitos dos fármacos , Nitratos/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Rim/metabolismo , Rim/patologia , Chumbo/sangue , Intoxicação por Chumbo/sangue , Intoxicação por Chumbo/fisiopatologia , Fígado/metabolismo , Fígado/patologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Metabolômica , Nitratos/sangue , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar
8.
World Neurosurg ; 138: 758-763, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32004735

RESUMO

OBJECTIVE: We sought to investigate the effects and mechanism of lead and a high-fat diet on cognitive function and the central nervous system in mice. METHODS: Eighty-four healthy male mice were randomly divided into a control group (n = 21) (fed with common diet and free drinking), a lead exposure group (n = 21) (fed with common diet and 300 mg/L lead acetate solution), a high-fat group (n = 21) (fed with high-fat diet and free drinking), and a lead + high-fat group (n = 21) (fed with high-fat diet and 300 mg/L lead acetate solution). In 10 weeks after lead exposure, the mice of all groups were tested for the cognition, learning and memory abilities, body weight, serum triglyceride (TG), low-density lipoprotein, and high-density lipoprotein, as well as for the contents of lead, interleukin 6 (IL-6), interleukin 17 (IL-17), interferon γ, advanced glycation end products (AGEs), glutathione S-transferase (GSH-ST), and hydrogen peroxide in the brain tissues. RESULTS: Compared with the control group and the lead-exposed group, the body weights of mice in the high-fat group and the lead + high-fat group increased significantly from the sixth week of the experiment, of which the difference was statistically significant (P < 0.05). Compared with the control group and the high-fat group, the lead content in brain tissue of the lead exposure group and the lead + high-fat group increased significantly, of which the difference was statistically significant (P < 0.05). Compared with the control group, the escape latent period, triglyceride, low-density lipoprotein, IL-6, IL-17, interferon γ, and AGEs of the remaining 3 groups increased significantly, but the recognition index, passing platform times, high-density lipoprotein, and GSH-ST significantly decreased (P < 0.05); the second and third escape latent periods, IL-6, IL-17, and AGEs of lead + high-fat group, were obviously higher than the remaining 3 groups, but the passing platform times were obviously lower than the remaining 3 groups, of which the difference was statistically significant. The content of hydrogen peroxide in brain tissues had no difference among groups (P > 0.05). CONCLUSIONS: The lead and high-fat diet resulted in lipid metabolism disorders and impaired the cognitive function and central nervous system by promoting the secretion of inflammatory factors in glial cells, inducing the inflammatory reaction of brain tissue, inhibiting GSH-ST expression, and increasing AGEs content.


Assuntos
Encéfalo/efeitos dos fármacos , Cognição/efeitos dos fármacos , Dieta Hiperlipídica , Intoxicação por Chumbo/psicologia , Chumbo/toxicidade , Animais , Encéfalo/metabolismo , Glutationa Transferase/efeitos dos fármacos , Glutationa Transferase/metabolismo , Produtos Finais de Glicação Avançada/efeitos dos fármacos , Produtos Finais de Glicação Avançada/metabolismo , Peróxido de Hidrogênio/metabolismo , Interferon gama/efeitos dos fármacos , Interferon gama/metabolismo , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Intoxicação por Chumbo/metabolismo , Lipoproteínas HDL/efeitos dos fármacos , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/efeitos dos fármacos , Lipoproteínas LDL/metabolismo , Masculino , Camundongos , Distribuição Aleatória , Triglicerídeos/metabolismo
9.
J Trace Elem Med Biol ; 58: 126429, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31760328

RESUMO

BACKGROUND AND AIM: Environmental lead (Pb) exposure damages the lungs and is a risk factor for death from cardiovascular disease. Pb induces toxicity by a mechanism, which involves alteration of the essential elements homeostasis. In this study we compare the effects of salinomycin (Sal), monensin (Mon) and meso-2,3-dimercaptosuccinic acid (DMSA) on the concentrations of lead (Pb), calcium (Ca), copper (Cu), iron (Fe) and zinc (Zn) in the lungs and heart of lead-exposed mice. METHODS: Sixty days old male ICR mice were divided into five groups: control (Ctrl) - untreated mice obtained distilled water for 28 days; Pb-intoxicated group (Pb) - exposed to 80 mg/kg body weight (BW) Pb(NO3)2 during the first 14 days of the experimental protocol; DMSA-treated (Pb + DMSA) - Pb-exposed mice, subjected to treatment with an average daily dose of 20 mg/kg BW DMSA for two weeks; Monensin-treated (Pb + Mon) - Pb-exposed mice, obtained an average daily dose of 20 mg/kg BW tetraethylammonium salt of monensic acid for 14 days; Pb + Sal - Pb-exposed mice, treated with an average daily dose of 20 mg/kg BW tetraethylammonium salt of salinomycinic acid for two weeks. On the 29th day of the experiment the samples (lungs and heart) were taken for atomic absorption analysis. RESULTS: The results revealed that exposure of mice to Pb for 14 days significantly increased the concentration of the toxic metal in both organs and elevated the cardiac concentrations of Ca, Cu and Fe compared to untreated mice. Pb exposure diminished the lung concentrations of Ca and Zn compared to that of untreated controls. DMSA, monensin and salinomycin decreased the concentration of Pb in the lungs and heart. Among the tested chelating agents, only salinomycin restored the cardiac Fe concentration to normal control values. CONCLUSION: The results demonstrated the potential application of polyether ionophorous antibiotic salinomycin as antidote for treatment of Pb-induced toxicity in the lungs and heart. The possible complexation of the polyether ionophorous antibiotics with Ca(II) and Zn(II), which can diminish the endogenous concentrations of both ions in the lungs should be taken into account.


Assuntos
Intoxicação por Chumbo/metabolismo , Pulmão/metabolismo , Metais Pesados/metabolismo , Monensin/farmacologia , Miocárdio/metabolismo , Piranos/farmacologia , Succímero/farmacologia , Animais , Cálcio/metabolismo , Cobre/metabolismo , Ferro/metabolismo , Chumbo/metabolismo , Masculino , Camundongos Endogâmicos ICR , Zinco/metabolismo
10.
J Chem Neuroanat ; 102: 101689, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31580902

RESUMO

Lead (Pb) is a non physiological metal that has been implicated in toxic processes affecting several organs and biological systems, including the central nervous system. Several studies have focused on changes in lead-associated neurobehavioral and neurochemical alterations that occur due to Pb exposure. The present study evaluates the effects of acute and chronic Pb acetate exposure on serotoninergic and dopaminergic systems within the dorsal raphe nucleus, regarding motor activity and anxiety behaviours. Experiments were carried out on adult male Meriones shawi exposed to acute lead acetate intoxication (25 mg/kg b.w., 3 i.p. injections) or to a chronic lead exposure (0,5%) in drinking water from intrauterine age to adult age. Immunohistochemical staining demonstrated that both acute and chronic lead exposure increased anti-serotonin (anti-5HT) and tyrosine hydroxylase (anti-TH) immuno-reactivities in the dorsal raphe nucleus. In parallel, our results demonstrated that a long term Pb-exposure, but not an acute lead intoxication, induced behavioural alterations including, hyperactivity (open field test), and anxiogenic like-effects. Such neurobehavioral impairments induced by Pb-exposure in Meriones shawi may be related to dopaminergic and serotoninergic injuries identified in the dorsal raphe nucleus.


Assuntos
Comportamento Animal/fisiologia , Dopamina/metabolismo , Núcleo Dorsal da Rafe/efeitos dos fármacos , Intoxicação por Chumbo/metabolismo , Compostos Organometálicos/toxicidade , Serotonina/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Núcleo Dorsal da Rafe/metabolismo , Gerbillinae , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Tirosina 3-Mono-Oxigenase/metabolismo
11.
Ecotoxicol Environ Saf ; 183: 109441, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31404725

RESUMO

OBJECTIVE: To explore the impacts of Pb exposure and the dimercaptosuccinic acid (DMSA) chelation therapy on bone metabolisms in young rats of different ages, as well as the potential mechanisms. METHOD: Young rats were exposed to 0.05%-0.1% Pb acetate for 19 days, during infanthood (postnatal day, PND2-20), childhood (PND21-39) and adolescenthood (PND40-58) respectively. In each developmental stage, rats were further divided into three subgroups: lead-exposed, one-course and two-course DMSA chelation therapy subgroups. Blood/bone lead concentrations, serum calciotropic hormones concentrations, and mRNA and protein expressions of bone turnover markers in the serum and bones were measured. Bone microstructures were analyzed using Micro-CT. RESULTS: Compared with lead-exposed during childhood and adolescenthood, increases in blood/bone lead levels, and the changes of blood/bone lead and trabecular bone microstructures after one-course DMSA chelation were most significant in rats lead-exposed during infanthood (P < .05). The serum osteocalcin (OC) concentrations, mRNA/protein expressions of OC and runt-related transcription factor 2 (RUNX2) in bones all decreased after Pb exposure, along with significant increases in serum C-terminal telopeptide of type I collagen (CTX) concentrations (P < .05). These effects were accompanied by changes of serum parathormone (PTH) and 1,25-dihydroxyvitamin D3 (1,25-(OH2)-D3) concentrations. DMSA chelation partially reversed the changes of bone microarchitectures, bone formation and resorption markers, and calciotropic-hormones, and the efficiency was greatest when the therapy was provided during infanthood. CONCLUSION: Developmental Pb exposure impaired bone microstructures and interfered bone metabolism, and the exposure effect was more obvious during infanthood than during childhood and adolescenthood. Lead effects were partially reversed by chelation therapy, and the efficacy may be most significant when the therapy was provided at younger ages.


Assuntos
Desenvolvimento Ósseo/efeitos dos fármacos , Osso e Ossos/metabolismo , Quelantes/uso terapêutico , Intoxicação por Chumbo/tratamento farmacológico , Chumbo/sangue , Succímero/uso terapêutico , Animais , Osso e Ossos/efeitos dos fármacos , Quelantes/administração & dosagem , Terapia por Quelação/métodos , Chumbo/metabolismo , Intoxicação por Chumbo/metabolismo , Intoxicação por Chumbo/fisiopatologia , Masculino , Ratos , Succímero/administração & dosagem
12.
Environ Sci Pollut Res Int ; 26(23): 23209-23218, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31243654

RESUMO

Lead (Pb) is a toxic heavy metal and an environmental pollutant, particularly because of its anthropogenic activity. The main impacts of Pb is recognized to cause injurious influences of various levels of the tropic chain, due to bio-accumulated lead causes many health issues such as intoxication of different body organs, such as kidneys and liver, and reproductive and nervous systems. Industrial lead toxicity has reduced as a result of the attempts to decrease the lead levels in the surrounding work environment. Conversably, health risks related with long-term environmental exposure to a low dose of Pb have been steadily demonstrated. Long-term exposure to lead toxicity caused inflammatory infiltration, degenerative changes in testicular tissues, reduction in spermatocytes, necrosis of hepatocytes, degeneration in renal tubules, and renal epithelium hypertrophy. Hence, we need an influential approach to vanquish lead toxicity. This consequence has emerged the necessity for potentially safe represent remedy, favorably keeping both enhancement and chelating of the antioxidant competences. Many antioxidants have been used for chelating heavy toxic pollutants such as lead and oxidative stress released in excess during lead exposure. Several studies have stated the noticeable gathering of herbal singly or in combination in modulating lead-induced disturbances, therefore proposing great promise in enhancing health status and welfare of man as well as animals. For this, in the current review, we tried to discuss the enormous harmful influences of lead toxicity on the animal model and the disturbing truth that this detrimental toxic substance can be found quite simply in the surroundings and amplitude.


Assuntos
Ração Animal/normas , Antioxidantes/farmacologia , Quelantes/farmacologia , Poluentes Ambientais/toxicidade , Intoxicação por Chumbo/prevenção & controle , Chumbo/toxicidade , Extratos Vegetais/farmacologia , Animais , Antioxidantes/administração & dosagem , Humanos , Intoxicação por Chumbo/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/administração & dosagem
13.
Cell Biol Int ; 43(6): 706-714, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30977573

RESUMO

Early exposure to lead (Pb) has been associated with an elevated risk of developing neurodegenerative diseases. There is evidence that neuronal damage in chronic Pb exposure can be caused by the convergence of glial damage. Apoptosis may be a possible mechanism of Pb-induced cell death in the central nervous system. We tested cellular damage and apoptosis in the spinal cord of Wistar rats treated with Pb. Twelve rats were divided into two groups (n = 6): the control group was treated with only drinking water and the other group received 500 ppm of Pb acetate. After 3 months of Pb treatment, all animals were euthanized and spinal cords were extracted. Morphology was evaluated by Nissl and Kluver-Barrera stainings. Apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Specific antibodies were used to evaluate Pb damage in oligodendrocytes, astrocytes, and microglia. A large number of apoptotic bodies was observed in the white matter of the Pb-treated group. The Pb-treated group also showed a reduced number of neurons and oligodendrocytes but had an increased number of astrocytes compared with the nontreated group. Our results demonstrate that chronic Pb treatment induces neurodegeneration, demyelination, and astrogliosis in the rat spinal cord.


Assuntos
Intoxicação por Chumbo/metabolismo , Chumbo/efeitos adversos , Medula Espinal/efeitos dos fármacos , Animais , Apoptose/fisiologia , Astrocitoma/metabolismo , Astrocitoma/fisiopatologia , Morte Celular/fisiologia , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/fisiopatologia , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Oligodendroglia/efeitos dos fármacos , Ratos , Ratos Wistar , Medula Espinal/metabolismo , Medula Espinal/fisiopatologia
14.
Behav Brain Res ; 366: 126-134, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-30878351

RESUMO

The literature on lead (Pb) exposure has focused in large part on hippocampal-based learning and memory deficits, although frontoexecutive dysfunctions are known to exist in Pb-exposed humans. This study examined the effects of perinatal (PERI) and early postnatal (EPN) developmental low-level Pb-exposures in rats on frontoexecutive functions, using the Attention Set-Shift Test (ASST). Control males and females performed the ASST similarly. Male EPN rats had difficulty with simple discrimination (SD) of odors and failed to complete the compound discrimination (CD) stage of the ASST. All other Pb-exposed rats completed the training and testing. Male PERI rats performed worse on the SD, intradimensional (ID), and intradimensional-reversal (ID-Rev) ASST stages when compared to male Control rats. Female EPN rats performed similar to Controls on the ID-Rev rats, whereas PERI rats performed better the trials-to-criterion on the ID-Rev than EPN and Control rats. Pb-exposed female rats had significant difficulty performing the ED/ED-Rev stages, with the number of trials-to-criterion double that required by Pb-exposed and Control male rats and Control female rats. Together, the ASST results showed that developmental Pb-exposure induces frontoexecutive dysfunction that persists into adulthood, with different sex-based vulnerabilities dependent upon the time-period of neurotoxicant exposure.


Assuntos
Atenção/efeitos dos fármacos , Função Executiva/efeitos dos fármacos , Intoxicação por Chumbo/metabolismo , Animais , Atenção/fisiologia , Modelos Animais de Doenças , Função Executiva/fisiologia , Feminino , Hipocampo/metabolismo , Chumbo/efeitos adversos , Masculino , Transtornos da Memória/metabolismo , Ratos , Ratos Long-Evans , Fatores Sexuais
15.
Toxicol Lett ; 306: 1-10, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30742882

RESUMO

Chronic lead (Pb) exposure has been shown to reduce the expression of some synaptic proteins which are involved in vesicular trafficking and affect presynaptic neurotransmitter release. However, the precise mechanisms by Pb impairs neurotransmitter release are still not well defined. In the current study, we aimed to elucidate the changes of Huntingtin-associated protein 1 (HAP1) in Pb exposed rats and PC12 cells models and its molecular mechanism. Repressor element-1 silencing transcription (REST) modulates the expression of genes containing the repressor element 1 (RE-1) cis-regulatory DNA sequence. HAP1 promoter region contains a RE-1 binding motif. We also observed whether Pb exposure regulated the HAP1 transcription level through influencing the expression of REST. Mother rats were exposed to 0.5 and 2 g/L Pb acetate (PbAc) in drinking water from the first day of gestation until postnatal 21 days, then the offspring rats were continued to drink PbAc for 1 year, while the control groups received drinking water. PC12 cells were divided into 3 groups: 0 µM, 1 µM and 100 µM PbAc. The results revealed that Pb levels in blood and brain of Pb exposed groups were significantly higher than that of the control group. The ability of learning and memory in Pb exposed rats was decreased. Pb exposure reduced the expression of HAP1 and increased the REST expression. Silencing REST could reverse the decreasing of HAP1 in Pb exposed PC12 cells. Our findings raise a possibility that the decreasing of HAP1 expression by Pb exposure may affect neurotransmitter release and results in impairments in spatial learning and memory ability.


Assuntos
Intoxicação por Chumbo/metabolismo , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/efeitos dos fármacos , Correpressor 1 de Receptor Nuclear/efeitos dos fármacos , Proteínas Repressoras/biossíntese , Proteínas Repressoras/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Feminino , Expressão Gênica/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Chumbo/sangue , Chumbo/metabolismo , Intoxicação por Chumbo/genética , Intoxicação por Chumbo/psicologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Células PC12 , Gravidez , RNA Interferente Pequeno/farmacologia , Ratos , Ratos Sprague-Dawley , Proteínas Repressoras/genética
16.
J Mol Model ; 25(1): 18, 2019 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-30610389

RESUMO

Melatonin has been proposed as an alternative treatment to the usage of EDTA for lead intoxication. In this computational paper, since previous work has not systematically studied the complexes that may be formed in the existing and proposed treatments, we study 45 possible complexes that we suggest may be formed between Pb and some essential metals with melatonin, melatonin metabolites, and EDTA, analyzing the stability and viability of these through the Gibbs free energy of complexation (ΔΔG), molecular orbitals, and energy decomposition analysis at the DFT level of theory PBE/TZ2P. Our findings show that most complexes present exergonic energies of reaction, and thus spontaneous complex formation. In addition, we show that the AMK and 3OHM melatonin metabolites possess electronic and thermodynamic properties adequate to act as lead trapping molecules due to the lower Pauli repulsion energies involved in the complexes they form and their large negative values of ΔΔG. Therefore, it is shown that both melatonin and some of its metabolites may be employed in a viable treatment for lead intoxication through formation of stable Pb-complexes. Graphical abstract Metal complexes formed with EDTA, melatonin, and its main metabolites.


Assuntos
Biologia Computacional/métodos , Complexos de Coordenação/química , Ácido Edético/química , Melatonina/química , Metais/química , Algoritmos , Animais , Sítios de Ligação , Complexos de Coordenação/metabolismo , Ácido Edético/metabolismo , Humanos , Chumbo/química , Chumbo/metabolismo , Intoxicação por Chumbo/metabolismo , Intoxicação por Chumbo/prevenção & controle , Melatonina/metabolismo , Metais/metabolismo , Modelos Moleculares , Estrutura Molecular , Eletricidade Estática , Termodinâmica
17.
J Expo Sci Environ Epidemiol ; 29(3): 416-423, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29706621

RESUMO

Childhood lead exposure has been shown to have a significant effect on neurodevelopment. Many of the biokinetics involved with lead biomarkers in children still remain unknown. Two hundred fifty (157 in the exposed group and 93 controls) children were enrolled in our study and lead exposed children returned for multiple visits for measurement of blood and bone lead and chelation treatment. We demonstrated that the correlation between blood and bone lead increased with subsequent visits. We calculated the blood lead half-life for 50 patients, and found a significant (p-value < 0.001) positive correlation with age. For ages 1-3 years (N = 17), the blood lead half-life was found to be 6.9 ± 4.0 days and for 3+ years it was found to be (N = 33) 19.3 ± 14.1 days. In conclusion, the turnover of lead in children is faster than in adults. Our results indicate that blood lead is a more acute biomarker of exposure than previously thought, which will impact studies of children's health using blood lead as a biomarker.


Assuntos
Exposição Ambiental , Intoxicação por Chumbo/metabolismo , Chumbo/farmacocinética , Adulto , Biomarcadores/metabolismo , Estudos de Casos e Controles , Criança , Pré-Escolar , China , Feminino , Meia-Vida , Humanos , Lactente , Masculino , Adulto Jovem
18.
Int J Biol Macromol ; 124: 716-723, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30448488

RESUMO

This study was designed to investigate the liver and kidney protective efficacy of a Lachnum polysaccharide (LEP) against Pb-induced toxicity in mice. The results showed that LEP decreased the Pb-induced bodyweight loss and organ index. Moreover, biochemical analysis showed that treatment of LEP could improve antioxidant status (CAT, GSH-Px and MDA) and the injury of tissues (liver and kidney). In addition, the histopathological observations indicated that LEP could attenuate liver and kidney cell injury induced by Pb. For further studies, key proteins involved in hepatic and kidney apoptosis, including cleaved caspase-3, Bax, Bcl-2, TGF-ß1 and α-SMA, were quantified. The present findings demonstrated that LEP is strongly effective in protecting against the liver and kidney injury induced by Pb. We hope this research can offer a theoretical base for development of polysaccharide based on nutraceutical food in future.


Assuntos
Ascomicetos/química , Rim/efeitos dos fármacos , Rim/patologia , Intoxicação por Chumbo/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Polissacarídeos/farmacologia , Substâncias Protetoras/farmacologia , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Biomarcadores , Biópsia , Modelos Animais de Doenças , Rim/metabolismo , Testes de Função Renal , Intoxicação por Chumbo/tratamento farmacológico , Intoxicação por Chumbo/metabolismo , Intoxicação por Chumbo/prevenção & controle , Fígado/metabolismo , Testes de Função Hepática , Masculino , Camundongos , Estresse Oxidativo , Polissacarídeos/química , Substâncias Protetoras/química
19.
Toxicol Mech Methods ; 29(4): 255-262, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30558515

RESUMO

Exposure to toxic elements is greatly unavoidable in our daily activities due to several routes of coming in contact with these elements. Thus lead (Pb), is one of the major causes of health hazard in human. In this study, evaluation of Zingiber officinale as mitigating measure against Pb induced biochemical and cytogenic toxicity in albino rats was investigated. Experimental rats were grouped into five with five animals per group, group I serves as control and groups 2-5 were induced intraperitoneal with lead acetate dissolved in distilled water at 3 mg/kg body weight whereas group 3-5 were orally administered with 200 mg/kg vitamin C, 200 mg/kg, and 100 mg/kg of Z. officinale, respectively for 7 d. The obtained results show that aspartate aminotransferase (AST), alkaline phosphatase (ALP), lipid peroxidation, urea, creatinine, bilirubin, and gamma-glutamyl transferase (GGT) were significantly increased (p < 0.05) and catalase (CAT) were reduced progressively in Pb alone induced rats. Hematological parameters showed a progressive reduction (p < 0.05) in lead acetate alone rats. There were significant changes in micronuclei (MN), chromosomal aberrations (CA) frequency, and oxidative damages in the bone marrow cells from lead acetate alone induced rats, although, mitotic index scores in these cells were reduced gradually (p < 0.05). The altered parameters were significantly reversed toward the levels observed in normal control rats administered with vitamin C and aqueous extract of Z. officinale. Hence, these results suggest that Z. officinale roots might contain therapeutic potential that can ameliorate the hazard effect of lead acetate poison.


Assuntos
Ácido Ascórbico/uso terapêutico , Intoxicação por Chumbo/prevenção & controle , Metabolismo dos Lipídeos/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Extratos Vegetais/uso terapêutico , Zingiber officinale/química , Animais , Ácido Ascórbico/administração & dosagem , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Intoxicação por Chumbo/genética , Intoxicação por Chumbo/metabolismo , Intoxicação por Chumbo/patologia , Masculino , Compostos Organometálicos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Ratos Wistar
20.
J Avian Med Surg ; 32(3): 217-220, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30204015

RESUMO

A 1.5-year-old Polish hen was presented with a history of watery droppings and poor vent tone. Results of diagnostic tests revealed blood lead at levels considered to be toxic. Chelation therapy was started with calcium ethylenediaminetetraacetate. The hen was laying eggs before, during, and after chelation therapy. Eggs were tested for the presence of lead by combining yolk and albumen together. Before chelation therapy, the level of lead in the egg tested was 14 µg. Two days after the end of chelation therapy, results of a second blood lead test revealed a drop to nontoxic levels. No lead was detected in the combined yolks and albumen of eggs collected 7-11 days after the end of chelation therapy. Four weeks after the end of chelation therapy, no lead was identified in the shells of tested eggs.


Assuntos
Quelantes de Cálcio/uso terapêutico , Galinhas , Ácido Edético/uso terapêutico , Ovos/análise , Intoxicação por Chumbo/veterinária , Doenças das Aves Domésticas/induzido quimicamente , Animais , Feminino , Contaminação de Alimentos/análise , Chumbo/análise , Chumbo/sangue , Intoxicação por Chumbo/metabolismo , Intoxicação por Chumbo/terapia , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/terapia
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