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1.
J Chromatogr A ; 1627: 461397, 2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823102

RESUMO

A new and sensitive analytical method for the simultaneous determination of secondary lipid peroxidation aldehydes has been successfully developed and validated. Malondialdehyde, acrolein, formaldehyde, acetaldehyde, propanal, and pentanal were extracted and derivatized using 2,4-dinitrophenylhydrazine (DNPH) by gas-diffusion microextraction (GDME) combined with dispersive liquid-liquid microextraction (DLLME) for gas chromatography-mass spectrometry (GC-MS) analysis. The experimental conditions have been optimized by experimental designs. The analytical method validation, in accordance to the Food and Drug Administration (FDA) guidance, provided good results in terms of linearity with r2≥0.9974, in the range from 0.15 or 0.3 µg·g-1 to 3 µg·g-1. Limits of detection and limits of quantification were 0.05 or 0.10 and 0.15 or 0.3 µg·g-1, respectively. Precision was tested as a relative standard deviation (RSD≤ 9.5%) and recoveries were between 95% and 110%. The method was applied in the characterization of aldehydes in forty-eight edible oil samples; with the highest concentration found in pomace olive oil for malondialdehyde at 6.64 µg·g-1.


Assuntos
Acetaldeído/análise , Acroleína/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Líquida/métodos , Malondialdeído/análise , Óleos Vegetais/análise , Acetaldeído/isolamento & purificação , Acroleína/isolamento & purificação , Aldeídos/análise , Aldeídos/isolamento & purificação , Limite de Detecção , Peroxidação de Lipídeos , Malondialdeído/isolamento & purificação , Azeite de Oliva/análise , Reprodutibilidade dos Testes
2.
Parasitol Res ; 119(9): 2783-2798, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32683559

RESUMO

Due to the increasing consumption of platinum (Pt), especially in automobile exhaust catalysts, environmental concentrations of Pt are of emerging concern worldwide. Limited information exists on environmental concentrations, particularly in Pt mining regions, while South Africa is the world's main supplier of Pt. Moreover, other metals are also released as by-products of Pt mining, which might also cause environmental concern. Certain fish parasite taxa have the ability to accumulate metals orders of magnitude higher than their hosts and can be used to reliably detect metals with naturally low abundance. Studies on Pt accumulation in parasite-host systems are limited. Therefore, the aims of the present study were (1) to determine the accumulation of a variety of metals (cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), platinum (Pt), and zinc (Zn)) in helminth fish parasites compared with their hosts from a reference site and an impoundment impacted by Pt mining activities; (2) to assess whether there is a difference between bioaccumulation of metals in infected and uninfected hosts, as well as between hosts with different infection intensities; and (3) to compare the biomarker responses (acetylcholine esterase activity (AChE), metallothionein content (MT), catalase activity (CAT), reduced glutathione content (GSH), malondialdehyde content (MDA), protein carbonyls induction (PC), superoxide dismutase activity (SOD), and cellular energy allocation (CEA)) between infected and uninfected hosts. The cestode Atractolytocestus huronensis accumulated significantly higher concentrations of Cr, Ni, and Pt than their host Cyprinus carpio, while the nematode Contracaecum sp. accumulated significantly higher concentrations of Pt and Zn than their host Clarias gariepinus. Infected fish showed lower metal concentrations compared to uninfected fish, while the parasites had no significant effects on their hosts' biomarker responses. The parasites demonstrated the bioavailability of metals derived from Pt mining activities and their ability to resist its toxic effects. Thus, these parasites are promising sensitive accumulation indicators for Cr, Ni, Pb, and Pt contaminations from Pt mining activities.


Assuntos
Bioacumulação/fisiologia , Cestoides/química , Metais Pesados/análise , Nematoides/química , Emissões de Veículos/análise , Poluentes Químicos da Água/análise , Acetilcolinesterase/metabolismo , Animais , Cádmio/análise , Cádmio/toxicidade , Carpas/parasitologia , Catalase/metabolismo , Peixes-Gato/parasitologia , Cobre/análise , Cobre/toxicidade , Ecossistema , Monitoramento Ambiental , Glutationa/análise , Malondialdeído/análise , Metalotioneína/análise , Metais Pesados/toxicidade , Parasitos , Platina/análise , Platina/toxicidade , África do Sul , Superóxido Dismutase/metabolismo , Emissões de Veículos/toxicidade , Poluentes Químicos da Água/toxicidade
3.
Acta Cir Bras ; 35(4): e202000406, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32578724

RESUMO

PURPOSE: To investigate the role of Rosmarinic acid (RA) in the prevention of traumatic brain injury and the immunohistochemical analysis of IBA-1 and GFAP expressions. METHODS: Healthy male rats were randomly divided into 3 groups consisting of 10 rats. Groups were as follows; control group, traumatic brain injury (TBI) group, and TBI+RA group. After traumatic brain injury, blood samples were taken from the animals and analyzed with various biochemical markers. And then IBA-1 and GFAP expressions were evaluated immunohistochemically. RESULTS: Significant results were obtained in all biochemical parameters between groups. Immunohistochemical sections showed IBA-1 not only in microglia and macrophage activity but also in degenerative neurons in blood vessel endothelial cells. However, GFAP reaction and post-traumatic rosmarinic acid administration showed positive expression in astrocytes with regular structure around the blood vessel. CONCLUSION: Rosmarinic acid in blood vessel endothelial cells showed that preserving the integrity of astrocytic structure in the blood brain barrier may be an important antioxidant.


Assuntos
Lesões Encefálicas Traumáticas/prevenção & controle , Proteínas de Ligação ao Cálcio/análise , Cinamatos/farmacologia , Craniotomia/métodos , Depsídeos/farmacologia , Proteína Glial Fibrilar Ácida/análise , Proteínas dos Microfilamentos/análise , Fármacos Neuroprotetores/farmacologia , Animais , Astrócitos/efeitos dos fármacos , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/cirurgia , Glutationa Peroxidase/análise , Imuno-Histoquímica , Masculino , Malondialdeído/análise , Distribuição Aleatória , Ratos Sprague-Dawley , Valores de Referência , Reprodutibilidade dos Testes
4.
Ecotoxicol Environ Saf ; 200: 110732, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32460049

RESUMO

This paper reports the role of exogenous glycine betaine (25 and 50 mM GB at a rate of 50 mL per plant) in enhancing NaCl-stress tolerance in common bean (Phaseolus vulgaris L.). Irrigating plants by simulated saline water, containing 0, 50 and 100 mM sodium chloride (NaCl), significantly reduced the growth dynamics, photosynthetic pigments (i.e., Chl a, Chl b, and carotenoids), membrane stability index (MSI), relative water content (RWC), and pod yield. While, malondialdehyde (MDA), endogenous proline, and glutathione contents, electrolyte leakage (EL), antioxidant defense system, and Na+ accumulation markedly increased upon exposure to NaCl-stress. However, the application of exogenous GB significantly improved salt tolerance of common bean as it increased the antioxidant defense including both enzymatic (i.e., peroxidase, superoxide dismutase, and catalase) and nonenzymatic (i.e., proline and glutathione) agents. Consequently, MSI, RWC, EL, and photosynthetic pigments have been improved recording significantly higher values than the control. Moreover, the pod yield increased by 29.8 and 59.4% when plants grown under 50 and 100 mM NaCl, respectively, were sprayed with 25 mM GB. Our results show that GB-induced slat tolerance in common bean plants mainly depends on the osmoregulation effect of GB and to a lesser extent on its antioxidant capacity. Foliar application of GB significantly reduced the accumulation of Na+ and at the same time induced K+ uptake maintaining a higher K+/Na+ ratio. Despite some changes in the activities of antioxidant enzymes induced by the application of GB, no consistent contribution in the salt tolerance could be cited in this study. Therefore, we suggest that salt tolerance is largely unrelated to the antioxidant defense ability of GB in common bean. While the potential role of GB in ameliorating salt tolerance is mainly due to the adjustment of ions uptake through limiting Na+ uptake and alternatively increasing K+ accumulation in plant tissues.


Assuntos
Betaína/farmacologia , Phaseolus/efeitos dos fármacos , Potássio/metabolismo , Tolerância ao Sal , Sódio/metabolismo , Antioxidantes/metabolismo , Transporte Biológico/efeitos dos fármacos , Catalase/metabolismo , Cátions , Glutationa/metabolismo , Malondialdeído/análise , Osmorregulação/efeitos dos fármacos , Peroxidase/metabolismo , Phaseolus/química , Phaseolus/enzimologia , Phaseolus/metabolismo , Fotossíntese/efeitos dos fármacos , Potássio/análise , Prolina/metabolismo , Sódio/análise , Superóxido Dismutase/metabolismo
5.
Zhongguo Zhong Yao Za Zhi ; 45(6): 1433-1439, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32281358

RESUMO

The aim of this study was to observe the protective effect of water extract from Sabia parviflora on mice with acute liver injury induced by acetaminophen, and investigate its possible mechanism. Fifty-eight Kunming mice were divided into 6 groups, 8 in the normal group, 10 in the model group, 10 in the biphenyl diester group, and 10 each in the low, medium and high dose groups. After adaptive feeding for one week, the mice in normal group were intragastrically administered with an equal volume of 0.5% sodium carboxymethylcellulose sodium(CMC-Na), and the mice in other groups were intragastrically administered with corresponding drugs at 20 mL·kg~(-1) once a day. Then acetaminophen(200 mg·kg~(-1)) was administered after the above drug administration except the normal group. The behavior and signs of the experimental animals were observed every day and the samples were taken for experiments on the next day of the final administration. The liver mass and mass index were calculated. The blood was collected from the abdominal aorta and centrifuged to obtain the serum for detecting aspartate aminotransferase(AST) activity and alanine aminotransferase(ALT) activity. The liver tissue homogenate was used to detect superoxide dismutase(SOD) activity, glutathione(glutathione, r-glutamyl cysteingl+glycine, GSH) activity and malondialdehyde(MDA) content. Liver tissue was analyzed for histological analysis. The results showed that S. parviflora could alleviate the lipid peroxidation damage in the liver caused by acetaminophen, reduce the ALT and AST activities in serum, increase the levels of SOD and GSH in liver tissue, decrease the content of MDA in liver tissue, and inhibit the apoptosis. S. parviflora could also improve the live histopathological profile, protect liver cells and restore liver function. Among them, the high dose had the most significant effect and showed dose-effect relationship. This study indicated that S. parviflora had a significant protective effect on acetaminophen-induced liver injury in mice, and its mechanism may be related to its anti-oxidation effect and inhi-bitory effect on apoptosis.


Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Fígado/enzimologia , Malondialdeído/análise , Camundongos , Estresse Oxidativo , Superóxido Dismutase/metabolismo
6.
Ecotoxicol Environ Saf ; 196: 110525, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32224370

RESUMO

Fragrant rice is a high-valued quality rice type which is gaining much popularity over the globe due to its better cooking qualities and special aromatic characteristics. Selenium (Se) and silicon (Si) could improve the growth and yield of rice; however, the combine effects of Se and Si (Se-Si treatments) on rice grain quality, aroma and lodging in fragrant rice were rarely investigated. The pot and field experiments were conducted with two fragrant rice cultivars i.e., Xiangyaxiangzhan and Yuxiangyouzhan, grown under three Se levels i.e., 0, 120, and 240 mg kg-1 of soil (for pot experiment) and 0, 300, and 600 kg ha-1 (for field experiment) regarded as LSe, MSe and HSe, respectively and two Si levels i.e., 0 and 60 mg kg-1 of soil (for pot experiment) and 0 and 150 kg ha-1 (for field experiment) regarded as -Si and +Si, respectively. Results depicted that the Se-Si treatments regulated head rice yield, grain yield and yield related traits and the HSe+Si treatment sustainably improved the grain yield and head rice yield by regulating plant growth, antioxidant response and malondialdehyde (MDA) contents in fragrant rice. The Se-Si treatments also improved the grain 2AP contents owing to regulation in the proline, pyrroline-5-carboxylate (P5C) and γ-aminobutyric acid (GABA) contents. Besides, Se-Si treatments also regulated the grain quality attributes and influenced the plant Se contents. Moreover, the Si mitigated Se-induced lodging resulted from changes in the lodging parameters i.e., lodging index, fresh weight per tiller, pushing resistance force, plant height and bending moment. Overall, the Se and Si application improved the grain yield and regulated the dry weight accumulation, antioxidant attributes and quality attributes. Meanwhile, the Si application mitigated the negative effect of Se-induced lodging in fragrant rice.


Assuntos
Grão Comestível/efeitos dos fármacos , Odorantes/análise , Oryza/efeitos dos fármacos , Selênio/farmacologia , Silício/farmacologia , Antioxidantes/análise , Relação Dose-Resposta a Droga , Grão Comestível/química , Grão Comestível/crescimento & desenvolvimento , Malondialdeído/análise , Oryza/química , Oryza/crescimento & desenvolvimento , Prolina/análise , Pirróis/análise , Solo/química
7.
J Anim Sci ; 98(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32207523

RESUMO

Broilers stocked in high densities may be prone to oxidative and inflammatory insults, resulting in impaired health status, growth performance, and meat quality. This study was to determine if 30% extra supplemental dl-methionine alleviated or prevented those adverse effects of a higher stocking density in broiler chickens. A total of 560 male Cornish Cross cockerels (day old) were divided into four groups: two stocking densities (9 and 12 birds/m2) and two supplementations of methionine (grower: 2.90 or 3.77 g/kg and finisher: 2.60 or 3.38 g/kg). Growth performance was recorded weekly. Blood and tissues were sampled at the end of each period. High stocking density decreased (P < 0.05) body weight and growth performance of growers and (or) finishers. Those differences were partially attenuated by the extra methionine supplementation. The high methionine elevated (P < 0.05) glutathione (GSH) concentration in the thigh at both ages (> 24%). The high stocking density elevated (>28%, P < 0.05) glutathione concentration in the plasma, breast, and thigh of growers, but decreased (P < 0.05) it in the liver of growers and thigh of finishers. Interaction effects (P < 0.05) between dietary methionine and stocking density were found on activities of the antioxidant enzyme glutathione S-transferase in the liver of growers and breast, thigh, and adipose tissue of finishers. The interaction effect was also found on activities of glutathione peroxidase and superoxide dismutase in the thigh of growers. The extra methionine decreased (P < 0.05) hepatic gene expression of heat shock protein 90 (18%) and thigh and breast malondialdehyde concentrations of the finishers (35%). In conclusion, the 30% extra dl-methionine supplementation was able to partially mitigate adverse effects caused by the higher stocking density and to improve the redox status of the broilers.


Assuntos
Antioxidantes/metabolismo , Galinhas/fisiologia , Suplementos Nutricionais/análise , Ácidos Graxos/análise , Metionina/farmacologia , Ração Animal/análise , Animais , Peso Corporal/efeitos dos fármacos , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Glutationa/análise , Glutationa Peroxidase/metabolismo , Fígado/metabolismo , Masculino , Malondialdeído/análise , Oxirredução , Superóxido Dismutase/metabolismo
8.
Anim Sci J ; 91(1): e13351, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32219964

RESUMO

This study investigated the effect of L-theanine on carcass traits, meat quality, muscle antioxidant capacity, and amino acid (AA) profiles of broilers. Three hundred 1-day-old Ross 308 male broilers were randomly allotted to five groups with six replicates. Birds were fed the basal diet or basal diet with 300, 600, 900, or 1,500 mg/kg L-theanine for 42 consecutive days. The results showed that L-theanine quadratically increased dressing percentage, eviscerated percentage, and leg muscle yield (p < .05). Meanwhile, drip loss, cooking loss, shear force, L*24h, and muscle lactate content decreased quadratically in response to dietary L-theanine supplementation (p < .05), while pH24h and muscle glycogen content were quadratically improved by L-theanine (p < .05). Notably, the contents of muscle malondialdehyde and protein carbonyl, and the activities of muscle total antioxidant capacity, catalase, and glutathione peroxidase decreased quadratically in response to dietary L-theanine supplementation (p < .05), suggesting that the oxidative stress level of muscle was decreased quadratically. Moreover, L-theanine quadratically increased the concentrations of most of muscle essential AA, nonessential AA, and flavor AA (p < .05). In conclusion, L-theanine can be used as a valuable feed additive to modulate carcass traits, meat quality, muscle antioxidant status, and AA profiles of boilers, and its optimum addition level is 600 mg/kg based on the present study.


Assuntos
Aminoácidos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Antioxidantes/metabolismo , Galinhas/metabolismo , Dieta/veterinária , Suplementos Nutricionais , Qualidade dos Alimentos , Glutamatos/administração & dosagem , Glutamatos/farmacologia , Carne/análise , Músculos/metabolismo , Aminoácidos/análise , Animais , Antioxidantes/análise , Glutationa Peroxidase/análise , Glutationa Peroxidase/metabolismo , Glicogênio/análise , Glicogênio/metabolismo , Ácido Láctico/análise , Ácido Láctico/metabolismo , Malondialdeído/análise , Malondialdeído/metabolismo
9.
J Nutr ; 150(5): 1116-1125, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32101618

RESUMO

BACKGROUND: Liver dysfunction impairs immunological homeostasis. Glycine (Gly) has been reported to have antioxidative and anti-inflammatory effects and to regulate apoptosis in various models. OBJECTIVES: The aim of the present study was to determine whether Gly could attenuate LPS-induced liver injury. METHODS: In Experiment 1, 48 6-week-old male C57BL/6 mice were randomly assigned into one of 4 groups: CON (control), GLY [orally administered Gly, 5 g · kg body weight (BW)-1 · d-1 for 6 d], LPS (5 mg/kg BW, intraperitoneally administered), and GLY + LPS (Gly supplementation, and on day 7 LPS treatment). In Experiment 2, mice were untreated, pretreated with Gly as above, or pretreated with Gly + l-buthionine sulfoximine (BSO) (0.5 g/kg BW, intraperitoneally administered every other day) for 6 d. On day 7, mice were injected with LPS as above. Histological alterations, activities of antioxidative enzymes, apoptosis, and immune cell infiltration were analyzed. RESULTS: In Experiment 1, compared with CON, LPS administration resulted in increased karyolysis and karyopyknosis in the liver by 8- to 10-fold, enhanced serum activities of alanine transaminase (ALT), aspartate transaminase (AST), and lactate dehydrogenase (LDH) by 1- to 1.8-fold, and increased hepatic apoptosis by 5.5-fold. Furthermore, LPS exposure resulted in increased infiltration of macrophages and neutrophils in the liver by 3.2- to 7.5-fold, elevated hepatic concentrations of malondialdehyde and hydrogen peroxide (H2O2), and elevated myeloperoxidase (MPO) activity by 1.5- to 6.3-fold. In Experiment 2, compared with the LPS group, mice in the GLY + LPS group had fewer histological alterations (68.5%-75.9%); lower serum ALT, AST, and LDH activities (24.3%-64.7%); and lower hepatic malondialdehyde and H2O2 concentrations (46.1%-80.2%), lower MPO activity (39.2%), immune cell infiltration (52.3%-85.3%), and apoptosis (69.6%), which were abrogated by BSO. Compared with the GLY + LPS group, mice in the GLY + BSO + LPS group had lower hepatic activities of catalase, superoxide dismutase, and glutathione peroxidase by 33.5%-48.5%; increased activation of NF-κB by 2.3-fold; and impaired nuclear factor (erythroid-derived 2)-like 2 signaling by 38.9%. CONCLUSIONS: Gly is a functional amino acid with an ability to protect the liver against LPS-induced injury in mice.


Assuntos
Apoptose/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Glicina/farmacologia , Inflamação/prevenção & controle , Lipopolissacarídeos/administração & dosagem , Fígado/efeitos dos fármacos , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Doença Hepática Induzida por Substâncias e Drogas/patologia , Peróxido de Hidrogênio/análise , L-Lactato Desidrogenase/sangue , Fígado/química , Macrófagos/patologia , Masculino , Malondialdeído/análise , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/patologia , Peroxidase/metabolismo
10.
Life Sci ; 246: 117400, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32032645

RESUMO

AIMS: Comparative sub-acute toxicity, including tolerance and dependence potential of fentanyl and its three novel and potent analogues was determined in mice. MAIN METHODS: Comparative sub-acute (21 d, intraperitoneal; 1/10 LD50) toxicity of fentanyl and its three novel analogues viz., N-(1-(2-phenoxyethyl)-4-piperidinyl) propionanilide (2), N-isopropyl-3-(4-(N-phenylpropionamido)piperidin-1-yl)propanamide (5), and N-t-butyl-3-(4-(N-phenylpropionamido)piperidin-1-yl)propanamide (6) was determined in mice. Animals were observed for additional seven days to assess the recovery. The brain, liver and kidney toxicity was assessed on the basis of various biochemical, oxidative, histological, and neuroadaptive markers. The expression levels of key neuronal markers associated with drug tolerance and dependence were investigated by western blot and immunohistochemistry. KEY FINDINGS: Fentanyl and its analogues caused abnormal levels of liver and kidney specific biomarkers in plasma. Brain malondialdehyde (MDA) levels were raised by all the treatments and kidney MDA level by analogue 6 (21 d). Reduced glutathione levels in brain, liver, and kidney were diminished by all the treatments (21 & 28 d) and a significant change in the levels of antioxidant enzymes was also produced mainly after 21 d. The deleterious effects of fentanyl and its analogues were further substantiated by corresponding histopathological changes in brain, liver and kidney (21 & 28 d). These compounds were also found to produce neuroadaptive changes as evidenced by the increased expression levels of c-Fos, glucocorticoid receptor, N-methyl-d-aspartate receptor1 and µ-opioid receptor (21 & 28 d). SIGNIFICANCE: Three novel analogues of fentanyl were envisaged to have alternative therapeutic potentials. However, their comparative sub-acute toxicity revealed undesirable side effects, thereby masking their therapeutic ability.


Assuntos
Fentanila/toxicidade , Animais , Biomarcadores/análise , Western Blotting , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Dano ao DNA/efeitos dos fármacos , Fentanila/análogos & derivados , Glutationa/análise , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/análise , Camundongos , Estresse Oxidativo/efeitos dos fármacos
11.
Mol Med Rep ; 21(3): 1233-1241, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32016469

RESUMO

The aim of the present study was to investigate the antioxidant mechanisms of dexmedetomidine against lung injury during intestinal ischemia reperfusion (IIR) in rats. The model of IIR­induced acute lung injury was established by occluding the superior mesenteric artery (SMA) for 1 h and reperfusing for 2 h using Sprague­Dawley rats. Pathological examination was used to assess the extent of the lung injury. Oxidative stress was evaluated by measuring malondialdehyde, myeloperoxidase and superoxide dismutase in the lung and plasma. The proinflammatory cytokines tumor necrosis factor­α and interleukin­6 were determined via an enzyme­linked immunosorbent assay. The mRNA and protein expression of nuclear factor­erythroid 2 related factor 2 (Nrf2) and heme oxygenase 1 (HO­1) were determined using a reverse transcription­quantitative polymerase chain reaction and western blotting. Pretreatment with dexmedetomidine significantly inhibited the oxidative stress response and proinflammatory factor release caused by IIR compared with the normal saline group (MDA and SOD in lung and plasma, P<0.05; MPO, IL­1ß and TNF­α in lung and plasma, P<0.05). Dexmedetomidine improved pulmonary pathological changes in IIR rats compared with the normal saline group. Investigations into the molecular mechanism revealed that dexmedetomidine increased the expression levels of Nrf2 and HO­1 via activating α2 adrenergic receptors compared with the normal saline group. The antagonism of α2 adrenergic receptors may reverse the protective effect of dexmedetomidine on lung injury during IIR, including decreasing the expression levels of Nrf2 and HO­1, elevating the oxidative stress response and increasing the proinflammatory factor release. In conclusion, pretreatment with dexmedetomidine demonstrated protective effects against lung injury during IIR via α2 adrenergic receptors. The Nrf2/HO­1 signaling pathway may serve a function in the protective effect of dexmedetomidine.


Assuntos
Lesão Pulmonar Aguda/prevenção & controle , Antioxidantes/farmacologia , Dexmedetomidina/farmacologia , Heme Oxigenase-1/metabolismo , Fator de Transcrição NF-E2/metabolismo , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Animais , Citocinas/efeitos dos fármacos , Modelos Animais de Doenças , Heme Oxigenase-1/genética , Pulmão/metabolismo , Pulmão/patologia , Masculino , Malondialdeído/análise , Fator de Transcrição NF-E2/genética , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/efeitos dos fármacos
12.
Int J Mol Sci ; 21(1)2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31906476

RESUMO

Bioactive collagen/chitosan complexes were prepared by an ion crosslinking method using fish skin collagen and chitosan solution as raw materials. Scanning electron microscopy observation confirmed that the collagen/chitosan complexes were of a uniform spherical shape and uniform particle size. The complexes were stable at different pH values for a certain period of time through swelling experiments. Differential scanning calorimetry (DSC) showed the collagen/ chitosan complexes were more stable than collagen. X-ray diffraction (XRD) showed that the complexes had a strong crystal structure, and Fourier transform infrared spectroscopy (FTIR) data revealed the changes in the secondary structure of the protein due to chitosan and TPP crosslinking. The content of malondialdehyde (MDA) in the complex treatment group was considerably lower, but the content of SOD was significantly higher than that of the collagen group or chitosan group. In addition, the collagen/chitosan complexes could considerably reduce melanin content, inhibit tyrosinase activity, and down-regulate tyrosinase mRNA expression. In conclusion, the collagen/chitosan complexes were potential oral protein preparation for antioxidant enhancement and inhibiting melanin synthesis.


Assuntos
Antioxidantes/farmacologia , Quitosana/química , Colágeno/química , Colágeno/farmacologia , Melaninas/biossíntese , Monofenol Mono-Oxigenase/antagonistas & inibidores , Animais , Varredura Diferencial de Calorimetria , Quitosana/farmacologia , Colágeno/ultraestrutura , Feminino , Concentração de Íons de Hidrogênio , Masculino , Malondialdeído/análise , Malondialdeído/metabolismo , Melaninas/análise , Melaninas/metabolismo , Melanoma Experimental , Camundongos , Microscopia Eletrônica de Varredura , Monofenol Mono-Oxigenase/genética , Monofenol Mono-Oxigenase/metabolismo , Tamanho da Partícula , Conformação Proteica , Espectroscopia de Infravermelho com Transformada de Fourier , Superóxido Dismutase/análise , Superóxido Dismutase/metabolismo , Difração de Raios X
13.
Oral Dis ; 26(4): 789-804, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31975475

RESUMO

Oral lichen planus (OLP) is a chronic disease with immune-mediated pathogenesis. Selenium (Se), an antioxidant, plays a role in modulating immunity. The aim of this clinical trial was to evaluate two Se forms (novel topical hydrogel and oral capsules), solely, in treating erosive OLP based on clinical evaluation and salivary oxidative stress markers. Patients were allocated into one of three groups: group I, topical corticosteroids; group II, topical Se; and group III, systemic Se. Treatment lasted for 6 weeks; patients were clinically evaluated at baseline, 6, and 12 weeks. Biochemical analysis for salivary malondialdehyde (MDA) and total antioxidant capacity (TAC) levels at baseline and 6 weeks was performed. There was a significant reduction in signs and symptoms in response to all treatment modalities. However, there was no significant difference among the three groups at 6 weeks. At 12 weeks, group II had significantly lower pain scores compared with group I. Salivary MDA levels showed a significant decrease in patients of group I and group III. TAC levels showed no significant difference in response to treatment. Selenium can be proposed as a treatment for OLP. Salivary MDA levels can be a biomarker for OLP disease severity.


Assuntos
Líquen Plano Bucal/tratamento farmacológico , Selênio/uso terapêutico , Antioxidantes/análise , Biomarcadores/análise , Humanos , Malondialdeído/análise , Estresse Oxidativo , Saliva/química
14.
Sci Rep ; 10(1): 1209, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31988350

RESUMO

In this study, the toxic effects of phenoxyethanol (Phy-Et), which is widely used in cosmetic industry, has been investigated with Allium test by means of physiological, cytogenetic, anatomical and biochemical parameters. To determine the changes in physiological reactions weight gain, relative injury rate, germination percentage and root length were investigated. Malondialdehyde, superoxide dismutase, glutathion and catalase levels were analyzed as biochemical parameters for determining the presence of oxidative stress. Mitotic index, micronucleus and chromosomal abnormality frequencies were studied as cytogenetic evaluation and the anatomical changes in root tip cells were investigated by cross sections. Changes in surface polarity and wettability were investigated by taking contact angle measurements of pressed root preparations. The mechanism of toxicity has been tried to be explained by these contact angles and this is the first study using contact angle measurements in toxicity tests. Consequently, exposure to Phy-Et resulted in a decrease in all measured physiological parameters and in mitotic index. In contrast, significant increases in the micronucleus and chromosomal abnormality frequencies were observed and the most significant toxic effect was found in 10 mM Phy-Et treated group. Phy-Et application induced oxidative damage and caused a significant increase in malondialdehyde level and a decrease in glutathione level compared to control group. Also a response occured against oxidative damage in superoxide dismutase and catalase activity and the activities increased in 2.5 mM and 5 mM Phy-Et treated groups and decreased in 10 mM Phy-Et treated groups. Furthermore, Phy-Et treatment resulted in some anatomical damages and changes such as necrosis, cell deformation and thickening of the cortex cell wall in root tip meristem cells of A. cepa. In the contact angle measurements taken against water, it was found that the wettability and hydrophilicity of the root preparations treated with Phy-Et were reduced, and this was the explanation of the growth abnormalities associated with water uptake. As a result, it was found that Phy-Et application caused toxic effects on many viability parameters and A. cepa test material was a reliable biomarker in determining these effects.


Assuntos
Etilenoglicóis/farmacologia , Cebolas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Raízes de Plantas/efeitos dos fármacos , Catalase/análise , Aberrações Cromossômicas/efeitos dos fármacos , Etilenoglicóis/administração & dosagem , Etilenoglicóis/toxicidade , Germinação/efeitos dos fármacos , Glutationa/análise , Malondialdeído/análise , Índice Mitótico , Cebolas/crescimento & desenvolvimento , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/toxicidade , Raízes de Plantas/crescimento & desenvolvimento , Medição de Risco , Superóxido Dismutase/análise , Chá/química , Molhabilidade/efeitos dos fármacos
15.
Medicina (Kaunas) ; 56(2)2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31972987

RESUMO

Background and objectives: Ample evidence indicates that oxidative stress, including complex lipid peroxidation processes, may play a significant role in the pathogenesis of colorectal cancer. The goal of this study was to evaluate selected oxidative stress markers in patients with colorectal cancer depending on some clinical features, with particular attention paid to the location of the primary tumor. Materials and Methods: The study was conducted on a group of 66 patients with colorectal cancer. The study consisted of two stages. The first stage involved the analysis of medical records; the second consisted of determining selected oxidative stress markers by measuring malondialdehyde as well as total oxidant and antioxidant status. Results: Of all patients, 43 (65.15%) had colon cancer, of whom 30 (69.77%) had a tumor on the left side and 13 (30.23%) had a tumor on the right side of the colon. Of all the patients, 23 (34.85%) had rectal cancer. The mean total oxidant and antioxidant status was 809.76 (SD ± 392.65) µmol/L and 253.19 (233.33-310.66) µmol/L, respectively. The mean malondialdehyde serum level was 2478.04 (SD ± 1397.05) ng/mL. The mean malondialdehyde serum concentration in patients with primary tumors located on the right side was higher in a statistically significant way compared with the remaining patients. Conclusions: It was demonstrated that the intensity of lipid peroxidation processes is correlated with the development of colorectal cancer, particularly on the right side. The results should be interpreted rather cautiously due to certain limitations of the study.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Colorretais/sangue , Estresse Oxidativo , Idoso , Biomarcadores Tumorais/sangue , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/fisiopatologia , Feminino , Humanos , Peroxidação de Lipídeos , Masculino , Malondialdeído/análise , Malondialdeído/sangue , Pessoa de Meia-Idade , Polônia
16.
Physiol Plant ; 168(3): 648-659, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31278755

RESUMO

The effects of low pH on antioxidant metabolism and nitrogen (N) assimilation in ginger seedlings under salt stress were investigated. A two-way randomized block design was used: the main treatment consisted of two pH levels, normal and low pH (6.0 and 4.0, respectively), and the other treatment consisted of two salinity levels, 0 and 100 mmol l-1 Na+ (NaCl and Na2 SO4 ). The results showed that low pH decreased the malondialdehyde (MDA) and hydrogen peroxide contents of ginger seedling leaves under salt stress. Moreover, low pH and salt stress significantly decreased the contents of non-enzymatic antioxidants, including ascorbate (AsA) and glutathione (GSH), and increased the activities of antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR) and glutathione reductase (GR). In addition, salt stress inhibited the N assimilation process in ginger seedling leaves, but low pH improved N assimilation under salt stress. Our finding was that low pH alleviated oxidative damage and promoted N assimilation under salt stress.


Assuntos
Antioxidantes/metabolismo , Gengibre/metabolismo , Nitrogênio/metabolismo , Estresse Salino , Ascorbato Peroxidases/metabolismo , Ácido Ascórbico/metabolismo , Catalase/metabolismo , Glutationa/metabolismo , Peróxido de Hidrogênio/análise , Concentração de Íons de Hidrogênio , Malondialdeído/análise , Estresse Oxidativo , Plântula/metabolismo , Superóxido Dismutase/metabolismo
17.
Physiol Plant ; 168(2): 345-360, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31343742

RESUMO

We conducted a study to evaluate the interactive effect of NO and H2 S on the cadmium (Cd) tolerance of wheat. Cadmium stress considerably reduced total dry weight, chlorophyll a and b content and ratio of Fv/Fm by 36.7, 48.6, 26.7 and 19.5%, respectively, but significantly enhanced the levels of hydrogen peroxide (H2 O2 ) and malondialdehyde (MDA), endogenous H2 S and NO, and the activities of antioxidant enzymes. Exogenously applied sodium nitroprusside (SNP) and sodium hydrosulfide (NaHS), donors of NO and H2 S, respectively, enhanced total plant dry matter by 47.8 and 39.1%, chlorophyll a by 92.3 and 61.5%, chlorophyll b content by 29.1 and 27.2%, Fv/Fm ratio by 19.7 and 15.2%, respectively, and the activities of antioxidant enzymes, but lowered oxidative stress and proline content in Cd-stressed wheat plants. NaHS and SNP also considerably limited both the uptake and translocation of Cd, thereby improving the levels of some key mineral nutrients in the plants. Enhanced levels of NO and H2 S induced by NaHS were reversed by hypotuarine application, but they were substantially reduced almost to 50% by cPTIO (a NO scavenger) application. Hypotuarine was not effective, but cPTIO was highly effective in reducing the levels of NO and H2 S produced by SNP in the roots of Cd-stressed plants. The results showed that interactive effect of NO and H2 S can considerably improve plant resistance against Cd toxicity by reducing oxidative stress and uptake of Cd in plants as well as by enhancing antioxidative defence system and uptake of some essential mineral nutrients.


Assuntos
Antioxidantes/fisiologia , Cádmio/toxicidade , Sulfeto de Hidrogênio/farmacologia , Óxido Nítrico/farmacologia , Estresse Oxidativo , Triticum/efeitos dos fármacos , Clorofila A/análise , Peróxido de Hidrogênio/análise , Malondialdeído/análise , Triticum/fisiologia
18.
Ecotoxicol Environ Saf ; 189: 109990, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31780206

RESUMO

The integrated effects of water flow on submerged macrophytes (Vallisneria natans) and leaf biofilms were comprehensively investigated in eutrophic microcosm. Changes in aquatic environmental factors were analyzed and water flow was found to elevate eutrophic water quality, especially in terms of TP removal. The removal efficiency of TP reached 78.95% in flowing water, which was more than 10-fold higher than in static water. Water flow altered the morphological and physiological characteristics of plants, decreasing the cell wall thickness and rate of photosynthesis, while promoting the accumulation of soluble sugar and protein in leaves. The starch content also increased with water flow, and significantly larger starch granules were observed in chloroplast. Furthermore, oxidative damage was evidenced by the consistently higher content of malondialdehyde in flowing water. Superoxide dismutase (SOD), peroxidase (POD) and Catalase (CAT) were induced in plants exposed to water flow, as an antioxidant stress response. The results of 16S rRNA high-throughput sequencing analysis showed that the structure of the biofilm microbial community changed in response to water flow. These results expand our understanding of the effects of water flow on submerged macrophytes and periphyton biofilms in eutrophic environments.


Assuntos
Hydrocharitaceae/fisiologia , Microbiota , Perifíton/fisiologia , Antioxidantes/metabolismo , Biofilmes , Hydrocharitaceae/metabolismo , Malondialdeído/análise , Malondialdeído/metabolismo , Fotossíntese , Folhas de Planta/metabolismo , RNA Ribossômico 16S/metabolismo , Água/química , Movimentos da Água
19.
J Sci Food Agric ; 100(3): 1099-1105, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31667840

RESUMO

BACKGROUND: γ-Aminobutyric acid (GABA) is a non-protein amino acid with several functions in the human body. Although freeze-thawing could effectively accumulate GABA in soybean sprouts, the mechanism has not been revealed. The mechanism by which freeze-thawing enhances GABA accumulation in germinated soybean was revealed by evaluating GABA content, the activity of related synthesis enzymes, and the microstructure of the tissues and cells of sprouts. The germinated soybeans were treated at different temperatures (from -196 °C to 25 °C) for 12 h and then thawed at 25 °C for 6 h. RESULTS: The results showed that GABA content in frozen soybean sprouts did not change significantly before thawing. After thawing, the GABA content of sprouts increased by 83.9% and 82.9% when treated by liquid nitrogen flash freeze at - 80 °C for 12 h compared with the control (4 °C treatment for 12 h). The results indicated that GABA formation mainly occurred during thawing. However, glutamate decarboxylase (GAD), diamine oxidase (DAO), and aminoaldehyde dehydrogenase (AMADH) activity decreased during thawing. Based on the malonaldehyde (MDA) content and microstructure of sprouts, it was suggested that freezing at lower temperatures (< -20 °C) maintained the integrity of the cell structure, while the tissues and cell membranes were broken during thawing. CONCLUSION: These results could provide evidence for the hypothesis that GABA formation resulted from full contact between enzymes and substrates during thawing, rather than the contribution of higher enzyme activity. © 2019 Society of Chemical Industry.


Assuntos
Produção Agrícola/métodos , Sementes/química , Soja/crescimento & desenvolvimento , Ácido gama-Aminobutírico/metabolismo , Amina Oxidase (contendo Cobre)/análise , Amina Oxidase (contendo Cobre)/metabolismo , Temperatura Baixa , Congelamento , Germinação , Glutamato Descarboxilase/análise , Glutamato Descarboxilase/metabolismo , Malondialdeído/análise , Malondialdeído/metabolismo , Proteínas de Plantas/análise , Proteínas de Plantas/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Soja/química , Soja/metabolismo , Ácido gama-Aminobutírico/análise
20.
Food Chem ; 309: 125604, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31689590

RESUMO

In this study, we extracted exopolysaccharides from Pythium arrhenomanes and purified them to obtain three polysaccharides (PEPS-1, PEPS-2, PEPS-3). The composition of these polysaccharides was determined. PEPS-2 and PEPS-3 showed outstanding antioxidant activities. PEPS-2 was chosen as a polysaccharide-based coating for strawberry fruit, and its effects on postharvest preservation of the fruit were determined. Strawberries coated with PEPS-2 exhibited significant delay in decay index and lower malondialdehyde, higher soluble solids content, anthocyanin content and vitamin C content, and greater DPPH radical-scavenging activity than uncoated control fruit. The developed method could be beneficial for improving the shelf-life of strawberries.


Assuntos
Conservação de Alimentos/métodos , Fragaria , Frutas , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Pythium/química , Antocianinas/análise , Ácido Ascórbico/análise , Armazenamento de Alimentos , Fragaria/química , Fragaria/fisiologia , Frutas/química , Frutas/fisiologia , Malondialdeído/análise , Polissacarídeos/análise
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