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1.
Neurotox Res ; 30(3): 380-91, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27126806

RESUMO

Alternatives for the treatment of amyotrophic lateral sclerosis (ALS) are scarce and controversial. The etiology of neuronal vulnerability in ALS is being studied in motor neuron-like NSC-34 cells to determine the underlying mechanisms leading to selective loss of motor neurons. One such mechanism is associated with mitochondrial oxidative stress, Ca(2+) overload, and low expression of Ca(2+)-buffering proteins. Therefore, in order to elicit neuronal death in ALS, NSC-34 cells were exposed to the following cytotoxic agents: (1) a mixture of oligomycin 10 µM and rotenone 30 µM (O/R), or (2) phenylarsine oxide 1 µM (PAO) (to mimic excess free radical production during mitochondrial dysfunction), and (3) veratridine 100 µM (VTD) (to induce overload of Na(+) and Ca(2+) and to alter distribution of Ca(2+)-buffering proteins [parvalbumin and calbindin-D28k]). Thus, the aim of the study was to test the novel neuroprotective compound ITH33/IQM9.21 (ITH33) and to compare it with riluzole on in vitro models of neurotoxicity. Cell viability measured with MTT showed that only ITH33 protected against O/R at 3 µM and PAO at 10 µM, but not riluzole. ITH33 and riluzole were neuroprotective against VTD, blocked the maximum peak and the number of [Ca(2+)]c oscillations per cell, and restored the effect on parvalbumin. However, only riluzole reversed the effect on calbindin-D28k levels. Therefore, ITH33 was neuroprotective against oxidative stress and Na(+)/Ca(2+) overload, both of which are involved in ALS.


Assuntos
Benzamidas/farmacologia , Glutamatos/farmacologia , Neurônios Motores/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Arsenicais , Calbindina 1/metabolismo , Cálcio/metabolismo , Cálcio/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Avaliação Pré-Clínica de Medicamentos , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neurônios Motores/patologia , Oligomicinas/toxicidade , Estresse Oxidativo/fisiologia , Parvalbuminas/metabolismo , Riluzol/farmacologia , Rotenona/toxicidade , Sódio/metabolismo , Sódio/toxicidade , Veratridina/toxicidade
2.
Plant Physiol Biochem ; 48(10-11): 813-21, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20846870

RESUMO

The potential of four essential cations (K(+), Ca(2+), Mg(2+) and Fe(2+)) to alleviate salt toxicity was studied in sage (Salvia officinalis L.) plants grown in pots. Two concentrations of the following chloride salts: KCl, CaCl2, MgCl2 and FeCl3, were used together with 100mM NaCl to study the effects of these nutrients on plant growth, leaf essential oils (EOs) and phenolic diterpenes composition. The sage plants accumulated Na(+) in their leaves (includers); this has affected secondary metabolites' biosynthesis. Treatment with 100mM NaCl slightly decreased borneol and viridiflorol, while increased manool concentrations. Addition of KCl, CaCl2 and MgCl2 increased considerably in a dose-dependent manner the oxygen-containing monoterpenes (1.8-cineole, camphor, ß-thujone and borneol) in 100mM NaCl-treated sage. Whereas, the contents of viridiflorol decreased further with the addition of KCl in 100mM NaCl-treated sage. Our results suggest that the changes in EOs composition were more related to K(+) and Ca(2+) availability than to Na(+) toxicity. Furthermore, treatment with NaCl decreased by 50% carnosic acid (CA), a potent antioxidant, content in the leaves. K(+) and Ca(2+) promoted the accumulation of CA and its methoxylated form (MCA) in the leaves. The concentration of CA was positively correlated with leaf K(+) (r=0.56, P=0.01) and Ca(2+) (r=0.44, P=0.05) contents. It appears that different salt applications in combination with NaCl treatments had a profound effect on EOs and phenolic diterpene composition in sage. Therefore, ionic interactions may be carefully considered in the cultivation of this species to get the desired concentrations of these secondary metabolites in leaf extracts.


Assuntos
Abietanos/metabolismo , Óleos Voláteis/metabolismo , Fenóis/metabolismo , Extratos Vegetais/metabolismo , Tolerância ao Sal/fisiologia , Sais/farmacologia , Salvia officinalis/efeitos dos fármacos , Cloreto de Sódio/toxicidade , Antioxidantes/metabolismo , Cálcio/metabolismo , Cálcio/farmacologia , Cloretos/metabolismo , Cloretos/farmacologia , Relação Dose-Resposta a Droga , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Potássio/metabolismo , Potássio/farmacologia , Tolerância ao Sal/efeitos dos fármacos , Sais/metabolismo , Salvia officinalis/crescimento & desenvolvimento , Salvia officinalis/metabolismo , Sódio/metabolismo , Sódio/toxicidade , Cloreto de Sódio/metabolismo , Estresse Fisiológico , Oligoelementos/metabolismo , Oligoelementos/farmacologia
3.
Appl Environ Microbiol ; 76(12): 4019-26, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20435777

RESUMO

Lotus species are forage legumes with potential as pastures in low-fertility and environmentally constrained soils, owing to their high persistence and yield under those conditions. The aim of this work was the characterization of phenetic and genetic diversity of salt-tolerant bacteria able to establish efficient symbiosis with Lotus spp. A total of 180 isolates able to nodulate Lotus corniculatus and Lotus tenuis from two locations in Granada, Spain, were characterized. Molecular identification of the isolates was performed by repetitive extragenic palindromic PCR (REP-PCR) and 16S rRNA, atpD, and recA gene sequence analyses, showing the presence of bacteria related to different species of the genus Mesorhizobium: Mesorhizobium tarimense/Mesorhizobium tianshanense, Mesorhizobium chacoense/Mesorhizobium albiziae, and the recently described species, Mesorhizobium alhagi. No Mesorhizobium loti-like bacteria were found, although most isolates carried nodC and nifH symbiotic genes closely related to those of M. loti, considered the type species of bacteria nodulating Lotus, and other Lotus rhizobia. A significant portion of the isolates showed both high salt tolerance and good symbiotic performance with L. corniculatus, and many behaved like salt-dependent bacteria, showing faster growth and better symbiotic performance when media were supplemented with Na or Ca salts.


Assuntos
Alphaproteobacteria/classificação , Alphaproteobacteria/isolamento & purificação , Lotus/microbiologia , Raízes de Plantas/microbiologia , Microbiologia do Solo , Alphaproteobacteria/efeitos dos fármacos , Alphaproteobacteria/genética , Proteínas de Bactérias/genética , Cálcio/toxicidade , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Dados de Sequência Molecular , N-Acetilglucosaminiltransferases/genética , Oxirredutases/genética , Filogenia , RNA Ribossômico 16S/genética , Recombinases Rec A/genética , Sais/toxicidade , Análise de Sequência de DNA , Sódio/toxicidade , Espanha
4.
J Biosci Bioeng ; 101(1): 77-9, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16503296

RESUMO

Uridine 5'-hexadecylphosphate (UMPC16) inhibited the growth of Saccharomyces cerevisiae under a hypersaline stress condition with Na+ more strongly than the calcineurin inhibitor cyclosporine A (CsA). Additional Ca2+ supplementation similarly suppressed the inhibitory activities of UMPC16 and CsA on yeast cell growth in a medium with Na+. UMPC16, but not CsA, accelerated mitochondrial reactive oxygen species (ROS) generation in combination with Na+, suggesting its inhibition of a Ca2+ -dependent but calcineurin-independent mechanism for protection against Na+ toxicity.


Assuntos
Cálcio/farmacologia , Estresse Oxidativo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/fisiologia , Sódio/toxicidade , Inibidores de Calcineurina , Ciclosporina/antagonistas & inibidores , Ciclosporina/farmacologia , Mitocôndrias/metabolismo , Pressão Osmótica , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Sódio/antagonistas & inibidores , Uridina Monofosfato/análogos & derivados , Uridina Monofosfato/antagonistas & inibidores , Uridina Monofosfato/farmacologia
5.
Ross Fiziol Zh Im I M Sechenova ; 91(9): 1097-107, 2005 Sep.
Artigo em Russo | MEDLINE | ID: mdl-16353485

RESUMO

Membrane-bound serine proteases to play a certain role in activation of sodium transport in epithelial cells. To were found explain the protease activity and sodium-dependent L-tryptophan transport across chicken small intestine interaction, four experiments were conducted. One hundred chicks were fed diets that contained 0; 0.3; 3 or 6% of supplemental NaCl and were given distillated water ad libitum. Signs of salt toxicity observed were as follows: a decreased body weight, increased heart and kidney weights, formation of secondary lysosomes in enterocytes and lymphocytes. Such chickens were in the state of negative nitrogen balance. Intestinal absorption of L-tryptophan correlated with mucosal protease activity during increased dietary sodium chloride intake. Recent in vitro and in vivo experiments indicate that enterocyte proteases may be of critical importance in activation of sodium-dependent intestinal transporters for L-tryptophan.


Assuntos
Absorção Intestinal/fisiologia , Mucosa Intestinal/enzimologia , Peptídeo Hidrolases/metabolismo , Sódio/metabolismo , Triptofano/metabolismo , Animais , Galinhas , Absorção Intestinal/efeitos dos fármacos , Mucosa Intestinal/citologia , Mucosa Intestinal/efeitos dos fármacos , Sódio/administração & dosagem , Sódio/toxicidade
6.
Lik Sprava ; (3-4): 132-5, 1995.
Artigo em Ucraniano | MEDLINE | ID: mdl-8819944

RESUMO

A new low-toxic antimicrobial preparation is proposed to impregnate woven materials used in treatment of pyo-inflammatory wounds contaminated with Gram-positive and Gram-negative bacteria as well as with pathogenic fungi as a result of an artificial infection. Sodic form of sudamate is less toxic, its bactericidal effect being 3-5 times more effective than that of hexachlorophene.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Sódio/uso terapêutico , Animais , Anti-Infecciosos Locais/toxicidade , Bandagens , Candidíase/tratamento farmacológico , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Cobaias , Hexaclorofeno/uso terapêutico , Hexaclorofeno/toxicidade , Humanos , Masculino , Compostos Orgânicos , Ratos , Sódio/toxicidade , Infecção dos Ferimentos/tratamento farmacológico
9.
Toxicol Lett ; 55(3): 263-72, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1848373

RESUMO

The proliferation response of rat renal pelvic epithelium, lined by transitional epithelium, to administration of various bladder cancer promoters was investigated. In addition, prostaglandin E2 (PGE2), lipid peroxide (LPO), malondialdehyde (MDA) and cyclic adenosine 3':5'-monophosphate (cyclic AMP) levels were assessed in urine of rats given the non-promoter L-ascorbic acid (AsA) and the promoters sodium L-ascorbate (AsA-Na) or sodium bicarbonate (NaHCO3) for 4 or 8 weeks. DNA synthesis in the renal pelvic epithelium, as assessed by 5-bromo-2'-deoxyuridine (BrdU) incorporation, was increased in the groups given AsA-Na, an extremely high dose of sodium chloride (NaCl), tert-butylhydroquinone (TBHQ) or ethoxyquin (EQ). Moreover, with the exception of AsA-Na, all treatments that induced an elevation of DNA synthesis also caused morphological epithelial alterations as observed by scanning electron microscopy (SEM). Treatment with butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) did not result in any proliferative response of the rat renal pelvis. No treatment-related changes in urinary PGE2 and cyclic AMP were noted, although AsA-Na and AsA but not NaHCO3 reduced levels of LPO and MDA in the urine. The results indicate that while the response of renal pelvic epithelium to certain bladder cancer promoters is similar to that of the bladder itself, none of the urinary cellular growth or free radical biochemical parameters is directly related to urothelial cell proliferation.


Assuntos
Carcinógenos , DNA/biossíntese , Pelve Renal/efeitos dos fármacos , Neoplasias da Bexiga Urinária/induzido quimicamente , Animais , Ácido Ascórbico/toxicidade , Bicarbonatos/toxicidade , Hidroxianisol Butilado/toxicidade , Hidroxitolueno Butilado/toxicidade , AMP Cíclico/urina , DNA/efeitos dos fármacos , Dinoprostona/urina , Epitélio/efeitos dos fármacos , Epitélio/ultraestrutura , Etoxiquina/toxicidade , Hidroquinonas/toxicidade , Pelve Renal/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Ratos , Ratos Endogâmicos F344 , Sódio/toxicidade , Bicarbonato de Sódio
10.
Carcinogenesis ; 10(9): 1733-6, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2548752

RESUMO

The promoting activities of low and high sodium or potassium ion concentrations, under conditions of neutral as well as elevated urinary pH, in urinary bladder carcinogenesis, were investigated in rats treated with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN). Male Wistar rats were given 0.05% BBN in their drinking water for 4 weeks and then treated for 32 weeks with either control diet (group 1) or this diet supplemented with equimolar amounts of the following minerals: 2.34% NaCl (group 2), 2.98% KCl (group 3), 3.36% NaHCO3 (group 4), 1.68% NaHCO3 + 2% KHCO3 (group 5), or 4% KHCO3 (group 6). The alkalizing salts NaHCO3 and KHCO3 induced comparable increases in urinary pH and elevated urinary sodium or potassium ion concentrations respectively. The combination of NaHCO3 + KHCO3 similarly caused an elevation of the urinary pH and less increased sodium and potassium ion concentrations. In the groups fed NaHCO3 and KHCO3 either alone or in combination, the incidences of papillary/nodular hyperplasia, papillomas and carcinomas in the urinary bladder had increased as compared to controls. NaCl and KCl also induced high urinary sodium or potassium ion concentrations without alteration of urinary pH. This was accompanied by increased incidences of simple hyperplasia, papillary/nodular hyperplasia, and/or papillomas but no carcinomas. The present results indicate that the potassium ion is as potent as the sodium ion in promoting urinary bladder carcinogenesis under conditions of elevated urinary pH, and that both the sodium and potassium ions may exert weak promoting activity under conditions of neutral urinary pH.


Assuntos
Butilidroxibutilnitrosamina/toxicidade , Carcinógenos/toxicidade , Nitrosaminas/toxicidade , Potássio/urina , Sódio/urina , Neoplasias da Bexiga Urinária/induzido quimicamente , Bexiga Urinária/patologia , Animais , Bicarbonatos/toxicidade , Concentração de Íons de Hidrogênio , Hiperplasia , Masculino , Papiloma/induzido quimicamente , Papiloma/patologia , Ratos , Ratos Endogâmicos , Sódio/toxicidade , Bicarbonato de Sódio , Bexiga Urinária/efeitos dos fármacos , Neoplasias da Bexiga Urinária/urina
11.
Gig Tr Prof Zabol ; (5): 30-2, 1989.
Artigo em Russo | MEDLINE | ID: mdl-2547700

RESUMO

Toxicity and hazards of sodium hydrocarbonate (SH) and potassium carbonate (PC) were experimentally assessed. Both substances caused impairments of electrolytic equilibrium, protein metabolism, changes of functional and biochemical indicators of the cardiovascular system, etc. LD50 of SH for white rats constituted 9940 +/- 350 mg/kg, for mice 3360 +/- 210 mg/kg and of PC 2980 +/- 142 and 2570 +/- 142 mg/kg, respectively. The authors failed to define mean lethal concentrations of both substances. The following threshold values Limac were established at 74 mg/m3 for SH and at 54 mg/m3 for PC. Limch was respectively 14.9 and 4.7 mg/m3. MAC for SH was established at 5 mg/m3 and for PC at 2 mg/m3.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Bicarbonatos/toxicidade , Carbonatos/toxicidade , Potássio/toxicidade , Sódio/toxicidade , Animais , Bicarbonatos/administração & dosagem , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Concentração Máxima Permitida , Ratos , Sódio/administração & dosagem , Bicarbonato de Sódio , Desequilíbrio Hidroeletrolítico/induzido quimicamente
12.
Princess Takamatsu Symp ; 16: 159-68, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3025161

RESUMO

The present studies report on the significance of L-ascorbic acid (AA) and urinary electrolytes for promotion of rat urinary bladder carcinogenesis. Male F344 rats were given an oral administration of 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) as an initiator for 4 weeks, and were then subjected to treatment with dietary supplements of test chemicals for 32 weeks. Administration of 5% sodium L-ascorbate (SA), the sodium ion form of AA significantly promoted urinary bladder carcinogenesis, whereas administration of 5% AA did not. The urine of rats given SA but not AA was characterized by an apparent elevation of pH, an increase of sodium ion concentration, and increases in the urinary content of total AA and its metabolite, dehydroascorbic acid. Administration of 3% NaHCO3, which induced elevation of pH and increase of sodium ion concentration in the urine, promoted BBN bladder carcinogenesis. When rats were given 5% AA plus 3% NaHCO3, AA enhanced the promoting activity of NaHCO3. Lowering of pH by 1% NH4Cl clearly reduced the promoting activity of 5% SA when these two compounds were given concurrently. Treatment with 5% AA plus 3% K2CO3 promoted BBN bladder carcinogenesis in rats, whereas addition of 5% CaCO3 or 5% MgCO3 to AA did not. These results strongly indicate the important role of urinary sodium or potassium ion concentration and pH in modulating urinary bladder carcinogenesis by AA.


Assuntos
Ácido Ascórbico/toxicidade , Eletrólitos/urina , Neoplasias da Bexiga Urinária/induzido quimicamente , Animais , Bicarbonatos/toxicidade , Butilidroxibutilnitrosamina , Carbonatos/toxicidade , Concentração de Íons de Hidrogênio , Masculino , Potássio/toxicidade , Ratos , Ratos Endogâmicos F344 , Sódio/toxicidade , Bicarbonato de Sódio , Neoplasias da Bexiga Urinária/urina , Urina
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