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1.
Biol Trace Elem Res ; 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32173789

RESUMO

Aluminum (Al)-induced bone metabolism disorder is a primary cause of osteoporosis. Ginsenoside Rg3 (Rg3) has demonstrated therapeutic properties in the treatment of osteoporosis. The present study aimed to identify potential bone protection mechanisms of Rg3 against Al-induced osteoporosis in rats. In this study, forty healthy male Sprague-Dawley rats were randomly allocated into groups in which they were treated with AlCl3 (64 mg/kg/day) and/or Rg3 (20 mg/kg/day). AlCl3 was given orally to rats for 120 days, and from the 91st day, treated orally with Rg3 for 30 days. Rg3 attenuated AlCl3-induced accumulation of Al by decreasing the bone mineral density in the lumbar spines, femoral metaphysis, and tibia, and inhibited AlCl3-induced oxidative stress in rat bone by decreasing the levels of reactive oxygen species and malondialdehyde, while increasing glutathione peroxidase and superoxide dismutase activity. Rg3 facilitated bone formation by increasing the concentration of calcium, phosphorus, amino-terminal propeptide of type I procollagen, and carboxyl-terminal propeptide of type I procollagen, bone alkaline phosphatase activity in serum, and type I collagen, osteocalcin, and osteopontin protein expressions. Rg3 inhibited bone resorption by decreasing the content of N-terminal cross-linking telopeptide of type I collagen, C-terminal cross-linking telopeptide of type I collagen, and tartrate-resistant acid phosphatase 5b activity in serum. Rg3 promoted the mRNA expression of growth regulation factors by increasing transforming growth factor-ß1, bone morphogenetic protein-2, insulin-like growth factor I, and core-binding factor α1. The results demonstrate that Rg3 can significantly attenuate Al accumulation, facilitate bone formation, inhibit bone resorption, resist oxidative stress, and promote the expression of factors that regulate growth. The results indicate that Rg3 is effective in alleviating AlCl3-induced osteoporosis.

2.
Nanoscale ; 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32103213

RESUMO

Artificial photosynthesis by a semiconductor-oxide-based photocatalysis is presently challenging due to low CO2 conversion rates and poor product selectivity. To promote CO2 reduction, Pt/TiO2 has been deemed as a classic photocatalyst. In this study, we restudy Pt/TiO2 for the thermally assisted photocatalytic reduction of CO2 and reveal a different story between photocatalysis and photothermal catalysis. For example, when using disordered Pt/TiO2-x, the CO2 conversion via photocatalysis at 298 K is not impressive. However, when the system temperature is increased to 393 K, the CO2 conversion rate is significantly enhanced by a factor of 155 as compared to that obtainable from pristine TiO2; further, surprisingly high selectivity of CH4 (87.5%) could be achieved. Thermally coupled photocatalysis yields the enhanced evolution of H2 side products over Pt (4.06 nm)/TiO2 and promoted H2 splitting over Pt (2.33 nm)/TiO2, which is seldom observed in conventional Pt/TiO2 photocatalysis. The synergy of improved charge separation at the Pt/TiO2-x interface induced by surface disordering and accelerated H2 consumption near smaller Pt nanoparticles by thermal assistance are believed to be critically important for the simultaneous enhancement of CO2 conversion rates and CH4 product selectivity. This study inspires revisiting not only Pt/TiO2 but also reactivating other semiconductor-oxide-based photocatalysts for use in thermally assisted photocatalysis.

3.
Dalton Trans ; 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32104856

RESUMO

A new family of non-centrosymmetric (NCS) compounds Sr6A4M4S16 (A = Ag, Cu; M = Ge, Sn) with mixed tetrahedral anionic ligands (AS4 and MS4) was successfully synthesized and characterized for the first time. All of the compounds exhibit excellent performances as promising infrared nonlinear optical (IR NLO) materials, with large NLO responses (1.1-2.0 × benchmark AgGaS2), high laser damage thresholds (2.0-4.5 × AgGaS2) and wide IR transmission ranges, and are nonhygroscopic. Moreover, their property modulation by the combination of different anionic groups was also discussed.

4.
J Agric Food Chem ; 68(3): 727-734, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31895560

RESUMO

T-2 toxin, an inevitable environmental pollutant, is the most toxic type A trichothecene mycotoxin. Reproductive disruption is a key adverse effect of T-2 toxin. Herein, this paper reviews the reproductive toxicity of T-2 toxin and its mechanisms in male and female members of different species. The reproductive toxicity of T-2 toxin is evidenced by decreased fertility, disrupted structures and functions of reproductive organs, and loss of gametogenesis in males and females. T-2 toxin disrupts the reproductive endocrine axis and inhibits reproductive hormone synthesis. Furthermore, exposure to T-2 toxin during pregnancy results in embryotoxicity and the abnormal development of offspring. We also summarize the research progress in counteracting the reproductive toxicity of T-2 toxin. This review provides information toward a comprehensive understanding of the reproductive toxicity mechanisms of T-2 toxin.


Assuntos
Reprodução/efeitos dos fármacos , Toxina T-2/toxicidade , Animais , Gametogênese/efeitos dos fármacos , Humanos
5.
Ying Yong Sheng Tai Xue Bao ; 31(1): 148-156, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31957391

RESUMO

Field experiment was conducted to examine the effects of combined application of N and Zn fertilizers on translocation, distribution, and accumulation of Zn in different organs in wheat plants. The results showed that Zn concentration and Zn accumulation in each organ were significantly different under different treatments. Compared with N3 (120 kg·hm-2), the grain Zn concentration of N1 (240 kg·hm-2) and N2 (180 kg·hm-2) increased 22.0% and 8.9%, respectively. Compared with the non-Zn application treatment (CK), grain Zn concentration under ZnS (soil Zn fertilization), ZnF (foliar Zn fertilization), and ZnS+ZnF (soil Zn fertilization combined with foliar Zn fertilization) treatments were increased by 5.4%, 60.5% and 72.8%, while Zn accumulation in grain were increased by 21.3% 82.5% and 102.4%, respectively. Zn in grain mainly came from the remobilization of Zn uptaken after antheis, with the accumulative contribution being 89.9% and 100.0% in ZnF and ZnS+ZnF, respectively. Compared with ZnS, Zn fertilizer recovery and use efficiency of ZnF and ZnS+ZnF were increased by 4.8, 1.1 times and 7.9, 2.2 times, respectively. Under current condition, Zn concentration and Zn accumulation in different organs of wheat increased with increasing N rate when it was less than 240 kg·hm-2, which was significantly increased in the grain by foliar Zn application. Therefore, Zn concentration and Zn accumulation in wheat grain could be increased by maintaining the high-yield N fertilization and combining the foliar Zn application in the late growth stage, which would improve Zn nutritional quality of wheat grain.


Assuntos
Triticum , Zinco , Grão Comestível , Fertilizantes , Nitrogênio , Solo
6.
Angew Chem Int Ed Engl ; 59(4): 1501-1505, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31634416

RESUMO

Acid functionalization of a carbon support allows to enhance the electrocatalytic activity of Pd to hydrogenate benzaldehyde to benzyl alcohol proportional to the concentration of Brønsted-acid sites. In contrast, the hydrogenation rate is not affected when H2 is used as a reduction equivalent. The different responses to the catalyst properties are shown to be caused by differences in the hydrogenation mechanism between the electrochemical and the H2 -induced hydrogenation pathways. The enhancement of electrocatalytic reduction is realized by the participation of support-generated hydronium ions in the proximity of the metal particles.

7.
Science ; 367(6473): 40-45, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31780624

RESUMO

Natural and synthetic nanoparticles composed of fivefold twinned crystal domains have distinct properties. The formation mechanism of these fivefold twinned nanoparticles is poorly understood. We used in situ high-resolution transmission electron microscopy combined with molecular dynamics simulations to demonstrate that fivefold twinning occurs through repeated oriented attachment of ~3-nanometer gold, platinum, and palladium nanoparticles. We discovered two different mechanisms for forming fivefold twinned nanoparticles that are driven by the accumulation and elimination of strain. This was accompanied by decomposition of grain boundaries and the formation of a special class of twins with a net strain of zero. These observations allowed us to develop a quantitative picture of the twinning process. The mechanisms provide guidance for controlling twin structures and morphologies across a wide range of materials.

8.
Braz J Med Biol Res ; 53(1): e9085, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31859914

RESUMO

Total Panax notoginseng saponin (TPNS) is the main bioactivity compound derived from the roots and rhizomes of Panax notoginseng (Burk.) F.H. Chen. The aim of this study was to investigate the effectiveness of TPNS in treating vascular neointimal hyperplasia in rats and its mechanisms. Male Sprague-Dawley rats were randomly divided into five groups, sham (control), injury, and low, medium, and high dose TPNS (5, 10, and 20 mg/kg). An in vivo 2F Fogarty balloon-induced carotid artery injury model was established in rats. TPNS significantly and dose-dependently reduced balloon injury-induced neointimal area (NIA) (P<0.001, for all doses) and NIA/media area (MA) (P<0.030, for all doses) in the carotid artery of rats, and PCNA expression (P<0.001, all). The mRNA expression of smooth muscle (SM) α-actin was significantly increased in all TPNS groups (P<0.005, for all doses) and the protein expression was significantly increased in the medium (P=0.006) and high dose TPNS (P=0.002) groups compared to the injury group. All the TPNS doses significantly decreased the mRNA expression of c-fos (P<0.001). The medium and high dose TPNS groups significantly suppressed the upregulation of pERK1/2 protein in the NIA (P<0.025) and MA (P<0.004). TPNS dose-dependently inhibited balloon injury-induced activation of pERK/p38MAPK signaling in the carotid artery. TPNS could be a promising agent in inhibiting cell proliferation following vascular injuries.


Assuntos
Lesões das Artérias Carótidas/prevenção & controle , Neointima/patologia , Panax notoginseng/efeitos dos fármacos , Saponinas/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Lesões das Artérias Carótidas/etiologia , Hiperplasia , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Regulação para Cima
9.
Chemosphere ; 234: 909-916, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31519099

RESUMO

T-2 toxin could impair male reproductive function. But, the toxicity mechanism is still unclear. In this study, male Kunming mice were orally administrated with T-2 toxin at the doses of 0, 0.5, 1 or 2 mg/kg body weight for 28 days. The fertility, body weight, reproductive organs volume, daily sperm production (DSP), and sperm malformation rate were detected. The expressions of testosterone (T) biosynthetic enzymes, luteinizing hormone (LH)-receptor, follicle stimulating hormone (FSH)-receptor and androgen binding protein (ABP) in testis were detected. The serum hormone level of gonadotropin-releasing hormone (GnRH), FSH, LH, T and progesterone (P), and the mRNA expression of GnRH, GnRH-receptor, LH and FSH were measured. These results demonstrated that T-2 toxin decreased body weight, reproductive organs volume and DSP, increased sperm malformation rate. T-2 toxin impaired fertility by decreasing the mating index, fertility index, numbers of implantation sites and viable fetuses, and increasing the number of animal with resorptions. Meantime, T-2 suppressed testicular function by inhibiting T biosynthesis and decreasing FSHR, LHR and ABP expression. Furthermore, the serum reproductive hormone contents and key factors expression of hypothalamic-pituitary-testis (HPT) axis were decreased by T-2 toxin. In summary, T-2 toxin impaired the male fertility by disrupting HPT axis and impairing testicular function.


Assuntos
Toxina T-2/toxicidade , Testículo/efeitos dos fármacos , Animais , Fertilidade , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Luteinizante/sangue , Masculino , Camundongos , Receptores do FSH/metabolismo , Receptores LHRH/metabolismo , Reprodução , Espermatozoides/metabolismo , Testículo/metabolismo , Testosterona/sangue
10.
Small ; 15(33): e1901966, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31225719

RESUMO

Nanoparticle (NP) superlattices have attracted increasing attention due to their unique physicochemical properties. However, key questions persist regarding the correlation between short- and long-range driving forces for nanoparticle assembly and resultant capability to predict the transient and final superlattice structure. Here the self-assembly of Ag NPs in aqueous solutions is investigated by employing in situ liquid cell transmission electron microscopy, combined with atomic force microscopy-based force measurements, and theoretical calculations. Despite the NPs exhibiting instantaneous Brownian motion, it is found that the dynamic behavior of NPs is correlated with the van der Waals force, sometimes unexpectedly over relatively large particle separations. After the NPs assemble into clusters, a delicate balance between the hydration and van der Waals forces results in a distinct distribution of particle separation, which is ascribed to layers of hydrated ions adsorbed on the NP surface. The study demonstrates pivotal roles of the complicated correlation between interparticle forces; potentially enabling the control of particle separation, which is critical for tailoring the properties of NP superlattices.

11.
Nanoscale ; 11(13): 5874-5878, 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30869110

RESUMO

We grew binary PbSe nanowires in an in situ gas-heating cell in a transmission electron microscope and elucidated species dependent mass transport pathways and key correlations among supersaturation, nucleation, and growth kinetics, thereby enabling morphological and compositional control of nanowires with tailored properties.

12.
Ecotoxicol Environ Saf ; 173: 131-141, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-30771656

RESUMO

The present study aimed to investigate whether melatonin (MT) treatment can attenuate immunotoxicity induced by aluminum chloride (AlCl3) in rat spleen. Forty-eight healthy male Wistar rats were randomly allocated and treated with AlCl3 and/or MT. Rats were orally administered with AlCl3 for 90 days, from 61st days, rats were injected intraperitoneally with MT for 30 days. Firstly, we found that MT relieved the AlCl3-induced immunosuppression by improving spleen structural damage, CD3+ and CD4+ T lymphocyte subsets, IL-2 and TNF-α mRNA expressions and decreasing CD8+ T lymphocyte subsets. Secondly, MT attenuated the AlCl3-induced oxidative stress in rat spleen by decreasing the levels of ROS and MDA, while increasing the activities of SOD and CAT. Thirdly, MT relieved the AlCl3-induced apoptosis in rat spleen by increasing the MMP and Bcl-2 mRNA and protein expressions, while decreasing apoptosis rates, activity of Caspase-3 and pro-apoptotic gene expression. Finally, MT increased Nrf2 nuclear translocation, and Nrf2 target genes (HO-1, NQO1, SOD1 and CAT) mRNA expressions in the spleen of AlCl3-exposed rat. These results suggest that MT may alleviate AlCl3-induced immunotoxicity by inhibiting oxidative stress and apoptosis associated with the activation of Nrf2 signaling pathway, which could lay the foundation for the treatment of AlCl3 immunotoxicity.


Assuntos
Cloreto de Alumínio/toxicidade , Apoptose/efeitos dos fármacos , Melatonina/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Masculino , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Baço/efeitos dos fármacos , Baço/imunologia , Baço/patologia
13.
Chem Biol Interact ; 299: 15-26, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30481499

RESUMO

Many reports demonstrated that aluminum maltolate (Almal) has potential toxicity to human and animal. Our study has demonstrated that Almal can induce oxidative damage and apoptosis in PC12 cells and SH-SY5Y Cells, two in vitro models of neuronal cells. Hyperforin (HF) is a well-known antioxidant, anti-inflammatory, anti-amyloid and anti-depressant compound extracted from Hypericum perforatum extract. Here, we investigated the neuroprotective effect of HF against Almal-induced neurotoxicity in cultured PC12 cells and SH-SY5Y cells, mainly caused by oxidative stress. In the present study, HF significantly inhibited the formation of reactive oxygen species (ROS), decreased the level of lipid peroxide and enhanced the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) compared with Almal group in PC12 cells and SH-SY5Y cells. Additionally, HF suppressed the reduction of the mitochondrial membrane potential (MMP), cytochrome c (Cyt-c) release, activation of caspase-3, and the down-regulation of Bcl-2 expression and up-regulation of Bax expression induced by Almal in PC12 cells and SH-SY5Y cells. In summary, HF protects PC12 cells and SH-SY5Y cells from damage induced by Almal through reducing oxidative stress and preventing of mitochondrial-mediated apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Floroglucinol/análogos & derivados , Terpenos/farmacologia , Animais , Caspase 3/metabolismo , Linhagem Celular Tumoral , Citocromos c/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Malondialdeído/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Compostos Organometálicos/toxicidade , Células PC12 , Floroglucinol/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Pironas/toxicidade , Ratos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
14.
Food Funct ; 9(12): 6427-6434, 2018 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-30462120

RESUMO

Oxidative stress is an important molecular mechanism for kidney injury in aflatoxin B1 (AFB1) nephrotoxicity. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a master transcription factor for regulating the cellular oxidative stress response, which has been confirmed in animal models. Lycopene (LYC), a natural carotenoid, has received extensive attention due to its antioxidant effect with the activation of Nrf2. However, the role of LYC in protecting against AFB1-induced renal injury is unknown. To evaluate the chemoprotective effect of LYC on AFB1-induced renal injury, forty-eight male mice were randomly divided into 4 groups and treated with LYC (5 mg per kg of bodyweight) and/or AFB1 (0.75 mg per kg of bodyweight) by intragastric administration for 30 days. AFB1 and LYC were respectively dissolved in olive oil. We found that AFB1 exposure significantly increased the serum concentrations of blood urea nitrogen (BUN) and serum creatinine (SCR), and caused damage to the renal structure. Notably, LYC potentially alleviated AFB1-induced kidney lesions through attenuating AFB1-induced oxidative stress. Renal nuclear factor-erythroid 2-related factor 2 (Nrf2) and its downstream target gene (CAT, NQO1, SOD1, GSS, GCLM and GCLC) translation and protein expression were ameliorated by pretreatment with LYC in AFB1-exposed mice. These results suggested that LYC potentially alleviates AFB1-induced renal injury. This effect may be attributed to the enhancement of renal antioxidant capacity with the activation of the Nrf2 antioxidant signaling pathway.


Assuntos
Aflatoxina B1/toxicidade , Antioxidantes/metabolismo , Nefropatias/tratamento farmacológico , Licopeno/administração & dosagem , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Catalase/genética , Catalase/metabolismo , Creatinina/sangue , Modelos Animais de Doenças , Humanos , Rim/diagnóstico por imagem , Rim/lesões , Rim/metabolismo , Nefropatias/etiologia , Nefropatias/genética , Nefropatias/metabolismo , Masculino , Camundongos , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
15.
ACS Nano ; 12(12): 12778-12787, 2018 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-30422615

RESUMO

Superlattice structures formed by nanoparticle (NP) self-assembly have attracted increasing attention due to their potential as a class of nanomaterials with enhanced physicochemical properties tailored by the assembly structure. However, many key questions remain regarding the correlation between the dynamics of individual NPs and emerging superlattice patterns. Here we investigated the self-assembly of gold NPs by employing in situ transmission electron microscopy equipped with direct detection camera capabilities, which enabled us to track the rapid motion of individual nanoparticles in real time. By calculating the contributions of Brownian, van der Waals, hydrodynamic, and steric hindrance forces, we obtained a quantitative evaluation of the competitive interactions that drive the assembly process. Such competition between forces over various separations is critical for the kinetics of cluster growth, leading to the superlattice formation. Brownian motion resulted in the formation of small-sized clusters, whose growth dynamics was characterized as reaction-limited aggregation. Subsequently, at relative short-range particle separations, van der Waals force overrode the Brownian force and dominantly drove the assembly process. When the particles were in close proximity, a delicate balance between van der Waals and steric hindrance forces led to an unexpected dynamic nature of the assembled superlattice. Our study provides a fundamental understanding of coupling energetics and dynamics of NPs involved in the assembly process, enabling the control and design of the structure of nanoparticle superlattices.

16.
Environ Pollut ; 243(Pt B): 1689-1695, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30300874

RESUMO

Aluminum (Al) has neurotoxicity that can result in cognitive dysfunction. Hippocampal dendritic spine loss is a pathological characteristic of cognitive dysfunction. Our previous study reported that Al exposure caused dendritic spine loss in the hippocampus, but the underlying mechanism remains unclear. In this study, rats were orally administered 50, 150 or 450 mg/kg of AlCl3 for 90 days. The dendritic spine density of the CA1 and DG regions was detected by Golgi-Cox staining. The F-actin/G-actin ratio, the expression of drebrin A and the components of the Rac 1/cofilin pathway were measured in the hippocampus. The results obtained showed that AlCl3 caused dendritic spine loss and decreased the F-actin/G-actin ratio. In addition, it was found that AlCl3 downregulated the expression of Rac 1, p-PAK, p-LIMK, p-cofilin and drebrin A and upregulated cofilin expression. Altogether, these results demonstrated that Al inactivated the Rac 1/cofilin pathway by inhibiting the phosphorylation of cofilin and the polymerization of F-actin, resulting in dendritic spine loss in the hippocampus.


Assuntos
Cloreto de Alumínio/toxicidade , Cofilina 1/antagonistas & inibidores , Disfunção Cognitiva/induzido quimicamente , Espinhas Dendríticas/patologia , Hipocampo/patologia , Proteínas rac1 de Ligação ao GTP/antagonistas & inibidores , Fatores de Despolimerização de Actina , Actinas/análise , Animais , Cofilina 1/biossíntese , Quinases Lim/biossíntese , Masculino , Neuropeptídeos/biossíntese , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Regulação para Cima , Quinases Ativadas por p21/biossíntese , Proteínas rac1 de Ligação ao GTP/biossíntese
17.
Food Chem Toxicol ; 116(Pt B): 307-314, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29704576

RESUMO

Exposure to aluminum (Al) inhibits bone formation, the principal mechanism possibly due to oxidative stress. However, little data is available that establishes the precise relationship. In this study, Wistar rats were exposed to 0 (GC), 0.4 (GL), 0.8 (GM) or 1.6 (GH) mg/L aluminum trichloride (AlCl3) in drinking water for 90 days, respectively. The concentrations of Al in serum and bone, serum markers of bone metabolism, bone mineral density (BMD) and body weight were measured. Histological changes within femurs were observed by H&E, ALP, and TRACP staining. Oxidative stress markers and JNK apoptotic pathway were detected in bone. The results indicate that AlCl3 exposure decreased BMD, numbers of ALP-positive osteoblasts and serum levels of bone formation markers (B-ALP, PICP and BGP), and caused damaged to the trabecular structure. Serum levels of bone resorption markers (TRACP-5b, CTX-I) and numbers of TRACP-positive osteoclasts increased in GL, but conversely, they decreased in GM and GH. In addition, AlCl3 caused oxidative stress, up-regulated expression of c-Jun and pro-apoptotic factors with increased p-JNK/JNK ratio and down-regulated expression of anti-apoptotic factor Bcl-2 in bone. Taken together, these results indicate that bone impairment caused by AlCl3 is associated with activation of the oxidative stress-mediated JNK apoptotic pathway.


Assuntos
Compostos de Alumínio/toxicidade , Apoptose , Osso e Ossos/efeitos dos fármacos , Cloretos/toxicidade , Sistema de Sinalização das MAP Quinases , Estresse Oxidativo , Fosfatase Alcalina/sangue , Fosfatase Alcalina/metabolismo , Cloreto de Alumínio , Compostos de Alumínio/sangue , Compostos de Alumínio/metabolismo , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Peso Corporal , Densidade Óssea/efeitos dos fármacos , Reabsorção Óssea , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/metabolismo , Cloretos/sangue , Cloretos/metabolismo , Colágeno Tipo I/sangue , Água Potável , Ativação Enzimática , Masculino , Osteoblastos/efeitos dos fármacos , Osteoblastos/enzimologia , Osteocalcina/sangue , Osteogênese/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pró-Colágeno/sangue , Ratos Wistar , Fosfatase Ácida Resistente a Tartarato/sangue
18.
Chemosphere ; 203: 170-178, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29614410

RESUMO

Aluminum (Al) is a recognized environmental pollutant that causes neuroinflammatory lesions, leading to neurodegenerative diseases. Interleukin-1 (IL-1) signaling pathway is responsible for regulating inflammatory lesions. However, it remains unclear whether IL-1 signaling pathway is involved in neuroinflammatory lesions induced by Al exposure. In the present study, one hundred and twenty Wistar rats were orally exposed to 0, 50, 150 and 450 mg/kg BW/d aluminum trichloride (AlCl3) for 90 days, respectively. We found that AlCl3 exposure increased hippocampal Al concentration, reduced hippocampus coefficient, impaired cognitive ability, deteriorated microstructure of hippocampal CA1 and CA3 regions, increased reactive oxygen species (ROS) level, activated astrocytes and microglia, increased pro-inflammatory cytokines contents and mRNA expressions, and decreased anti-inflammatory cytokines contents and mRNA expressions in the hippocampus. These results indicated that AlCl3 induced the hippocampal inflammatory lesion (HIL). Moreover, AlCl3 exposure increased the mRNA and protein expression of IL-1 signaling pathway core components in the hippocampus, demonstrating that AlCl3 activated IL-1 signaling pathway. Furthermore, the correlation between interleukin-1ß (IL-1ß) content and HIL and activation of the IL-1 signaling pathway was analyzed. Results showed that IL-1ß content was positively correlated with pro-inflammatory cytokines contents and mRNA expressions and activation of IL-1 signaling pathway, and was negatively correlated with hippocampus coefficient, anti-inflammatory cytokines contents and mRNA expressions, and the number of hippocampal neurons. The above results demonstrate that AlCl3-induced HIL is associated with IL-1 signaling pathway, in which IL-1ß is a link.


Assuntos
Compostos de Alumínio/toxicidade , Cloretos/toxicidade , Hipocampo/patologia , Interleucina-1beta/metabolismo , Transdução de Sinais , Alumínio/metabolismo , Cloreto de Alumínio , Animais , Citocinas/metabolismo , Hipocampo/metabolismo , Inflamação/induzido quimicamente , Neurônios/metabolismo , Ratos , Ratos Wistar
19.
Biol Trace Elem Res ; 185(2): 433-439, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29520724

RESUMO

Aluminum (Al) exposure has adverse effects on osteoblasts, and the effect might be through autophagy-associated apoptosis. In this study, we showed that aluminum trichloride (AlCl3) could induce autophagy in MC3T3-E1 cells, as demonstrated by monodansylcadaverine (MDC) staining and the expressions of the ATG3, ATG5, and ATG9 genes. We found AlCl3 inhibited MC3T3-E1 cell survival rate and caused apoptosis, as evidenced by CCK-8 assay, Annexin V/PI double staining, and increased expressions of Bcl-2, Bax, and Caspase-3 genes. In addition, increased autophagy induced by rapamycin further attenuated the MC3T3-E1 cell apoptosis rate after AlCl3 exposure. These results support the hypothesis that autophagy plays a protective role in impeding apoptosis caused by AlCl3. Activating autophagy may be a strategy for treatment of Al-induced bone disease.


Assuntos
Cloreto de Alumínio/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/fisiologia , Células 3T3 , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Camundongos
20.
Toxicol Lett ; 285: 132-138, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29309810

RESUMO

Aluminum (Al) is a toxic metal, and excessive Al accumulation causes immunosuppression. Deferiprone (DFP) is a well-known chelator and used in dialysis patients for removing Al from tissues. The present study aimed to investigate whether DFP treatment can attenuate immunotoxicity induced by aluminum chloride (AlCl3) in cultured lymphocytes. Lymphocytes were treated with 0 and 0.6 mmol/L AlCl3∙6H2O (pH 7.2) and/or 1.8 mmol/L DFP, respectively. Immune function of lymphocytes was assessed by T and B lymphocytes proliferation rates, T lymphocyte subpopulations and IL-2, IL-6 and TNF-α contents. In addition, lymphocyte damage was assessed by LDH activity, NO and MDA contents, NOS, SOD and GSH-Px activities, lymphocyte apoptosis index. These results showed that AlCl3 exposure reduced T and B lymphocyte proliferation rates, CD3+ and CD4+ T lymphocyte subpopulations, CD4+/CD8+ ratio, IL-2, IL-6 and TNF-α contents, SOD and GSH-Px activities, early and later lymphocyte apoptosis indexes while enhanced CD8+ T lymphocyte subpopulation, NO and MDA contents, LDH activity. DFP treatment attenuated the immunotoxicity of lymphocytes and reduced oxidative stress and lymphocyte apoptosis induced by AlCl3, indicating that DFP could protect lymphocytes against immunosuppression induced by AlCl3 through attenuating oxidative stress and apoptosis.


Assuntos
Compostos de Alumínio/toxicidade , Apoptose/efeitos dos fármacos , Quelantes/farmacologia , Cloretos/toxicidade , Linfócitos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Piridonas/farmacologia , Cloreto de Alumínio , Animais , Células Cultivadas , Citocinas/imunologia , Deferiprona , Tolerância Imunológica/efeitos dos fármacos , Linfócitos/imunologia , Linfócitos/metabolismo , Linfócitos/patologia , Ratos Wistar
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