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1.
Biogerontology ; 18(4): 665-677, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28643190

RESUMO

Idebenone, the synthetic analog of coenzyme Q10 can improve electron transport in mitochondria. Therefore, it is used in the treatment of Alzheimer's disease and other cognitive impairments. However, the mechanism of its action on neurodevelopment is still to be elucidated. Here we demonstrate that the cellular response of human induced pluripotent stem cells (hiPSC) to idebenone depends on the stage of neural differentiation. When: neural stem cells (NSC), early neural progenitors (eNP) and advanced neural progenitors (NP) have been studied a significant stimulation of mitochondrial biogenesis was observed only at the eNP stage of development. This coexists with the enhancement of cell viability and increase in total cell number. In addition, we report novel idebenone properties in a possible regulation of neural stem cells fate decision: only eNP stage responded with up-regulation of both neuronal (MAP2), astrocytic (GFAP) markers, while at NSC and NP stages significant down-regulation of MAP2 expression was observed, promoting astrocyte differentiation. Thus, idebenone targets specific stages of hiPSC differentiation and may influence the neural stem cell fate decision.


Assuntos
Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Biogênese de Organelas , Ubiquinona/análogos & derivados , Biomarcadores , Linhagem Celular , Linhagem da Célula , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Fenótipo , Espécies Reativas de Oxigênio/metabolismo , Ubiquinona/farmacologia
2.
Toxicol In Vitro ; 45(Pt 3): 434-444, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28578007

RESUMO

Pyrroloquinoline quinone (PQQ) is a factor influencing on the mitochondrial biogenesis. In this study the PQQ effect on viability, total cell number, antioxidant capacity, mitochondrial biogenesis and differentiation potential was investigated in human induced Pluripotent Stem Cells (iPSC) - derived: neural stem cells (NSC), early neural progenitors (eNP) and neural progenitors (NP). Here we demonstrated that sensitivity to PQQ is dependent upon its dose and neural stage of development. Induction of the mitochondrial biogenesis by PQQ at three stages of neural differentiation was evaluated at mtDNA, mRNA and protein level. Changes in NRF1, TFAM and PPARGC1A gene expression were observed at all developmental stages, but only at eNP were correlated with the statistically significant increase in the mtDNA copy numbers and enhancement of SDHA, COX-1 protein level. Thus, the "developmental window" of eNP for PQQ-evoked mitochondrial biogenesis is proposed. This effect was independent of high antioxidant capacity of PQQ, which was confirmed in all tested cell populations, regardless of the stage of hiPSC neural differentiation. Furthermore, a strong induction of GFAP, with down regulation of MAP2 gene expression upon PQQ treatment was observed. This indicates a possibility of shifting the balance of cell differentiation in the favor of astroglia, but more research is needed at this point.


Assuntos
Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Cofator PQQ/farmacologia , Antioxidantes/metabolismo , Contagem de Células , Diferenciação Celular , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Dosagem de Genes , Proteína Glial Fibrilar Ácida/biossíntese , Humanos , Potencial da Membrana Mitocondrial , Proteínas Associadas aos Microtúbulos/biossíntese , Proteínas Associadas aos Microtúbulos/genética , Mitocôndrias , Proteínas Mitocondriais/biossíntese , Proteínas Mitocondriais/genética , Fator 1 Nuclear Respiratório/biossíntese , Fator 1 Nuclear Respiratório/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/biossíntese , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética
3.
Heart Lung Vessel ; 6(1): 52-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24800198

RESUMO

INTRODUCTION: Pilot study associating hemodialysis-to-general-anesthesia time interval and post-operative complications in hemodialysis patients to better define a more optimal pre-anesthetic waiting period. METHODS: Pre-anesthetic and 48-hours post-anesthetic parameters (age, gender, body-mass-index, pre-operative ultrafiltrate, potassium, renal disease etiology, hemodialysis sessions per week, Acute Physiology and Chronic Health Evaluation-II score, Portsmouth-Physiologic and Operative Severity Score for the Enumeration of Mortality and Morbidity, American Society of Anesthesiologists physical status, Johns Hopkins Surgical Classification System Category, surgical urgency, intra-operative fluids, estimated blood loss, post-operative complications) were collected on chronic hemodialysis patients between 11/2009-12/2010. Continuous data were analyzed by Analysis of Variance or t-test. Bivariate data were analyzed by Fisher's Exact Test. Relative Risks/Confidence Intervals were calculated for statistically significant comparisons (p=0.05). Exclusion criteria were incomplete records, peritoneal dialysis, intra-operative hemodialysis, liver transplant, and cardiopulmonary bypass. RESULTS: Patients were grouped by dialysis to anesthesia time interval: Group 1 >24 hours, Group 2 7-23.9 hours, Group 3 < 7 hours. Among Surgical Category 3-5 patients, hypotension was more common in Group 3 than Group 1 (63.6% vs 9.2%, p<0.0001, relative risk=6.9, confidence interval=3.0-15.7) or Group 2 (63.6% vs 17.3%, p=0.0002, relative risk=3.7, confidence interval=1.9-7.2). Other complications rates were not statistically significant. Disease and surgical severity scores, preoperative ultrafiltrate, and intra-operative fluids were not different. CONCLUSIONS: Post-anesthetic hypotension within 48 hours was more common in those with < 7 hours interval between dialysis and anesthesia. Therefore, if surgical urgency permits, a delay of ≥7 hours may limit postoperative hypotension. More precise associations should be obtained through a prospective study.

4.
Antimicrob Agents Chemother ; 45(8): 2198-203, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11451674

RESUMO

Tetracycline (TET) is a front-line antibiotic for the treatment of chlamydial infections in both humans and animals, and the emergence of TET-resistant (Tet(r)) Chlamydia is of significant clinical importance. Recently, several Tet(r) chlamydial strains have been isolated from swine (Sus scrofa) raised in production facilities in Nebraska. Here, the intracellular development of two Tet(r) strains, R19 and R27, is characterized through the use of tissue culture and immunofluorescence. The strains grow in concentrations of up to 4 microg of TET/ml, while a TET-sensitive (Tet(s)) swine strain (S45) and a strain of the human serovar L2 (LGV-434) grow in up to 0.1 microg of TET/ml. Although inclusions form in the presence of TET, many contain large aberrant reticulate bodies (RBs) that do not differentiate into infectious elementary bodies. The percentage of inclusions containing typical developmental forms decreases with increasing TET concentrations, and at 3 microg of TET/ml 100% of inclusions contain aberrant RBs. However, upon removal of TET the aberrant RBs revert to typical RBs, and a productive developmental cycle ensues. In addition, inclusions were found that contained both C. suis R19 and Chlamydia trachomatis L2 after sequential infection, demonstrating that two biologically distinct chlamydial strains could both develop within a single inclusion.


Assuntos
Resistência a Tetraciclina , Tetraciclina/farmacologia , Animais , Antibacterianos/farmacologia , Chlamydia/efeitos dos fármacos , Chlamydia/crescimento & desenvolvimento , Humanos , Corpos de Inclusão/ultraestrutura , Testes de Sensibilidade Microbiana , Sulfadiazina/farmacologia , Suínos
6.
Acta Biochim Pol ; 46(1): 203-10, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10453996

RESUMO

1,12-Dodecanedioic acid, the end-product of omega-hydroxylation of lauric acid, stimulates in a concentration dependent manner, phosphatidylethanolamine synthesis via ethanolamine-specific phospholipid base exchange reaction in rat liver endoplasmic reticulum. On the other hand, administration to rats of 10-undecynoic acid, a specific inhibitor of omega-hydroxylation reaction catalyzed by cytochrome P450 4A1, inhibits the ethanolamine-specific phospholipid base exchange activity by 30%. This is accompanied by a small but significant decrease in phosphatidylethanolamine content in the endoplasmic reticulum and inhibition of cytochrome P450 4A1. On the basis of these results it can be proposed that a functional relationship between cytochrome P450 4A1 and phosphatidylethanolamine synthesis exists in rat liver. Cytochrome P450 4A1 modulates the cellular level of lauric acid, an inhibitor of phospholipid synthesis. In turn, ethanolamine-specific phospholipid base exchange reaction provides molecular species of phospholipids, containing mainly long-chain polyunsaturated fatty acid moieties, required for the optimal activity of cytochrome P450 4A1.


Assuntos
Inibidores das Enzimas do Citocromo P-450 , Inibidores Enzimáticos/farmacologia , Ácidos Graxos Insaturados/farmacologia , Microssomos Hepáticos/efeitos dos fármacos , Oxigenases de Função Mista/antagonistas & inibidores , Fosfatidiletanolaminas/metabolismo , Animais , Citocromo P-450 CYP4A , Masculino , Microssomos Hepáticos/enzimologia , Ratos , Ratos Wistar
7.
FEBS Lett ; 434(1-2): 101-7, 1998 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-9738460

RESUMO

The results of the present investigation relate the effects of the nutritional state and administration of clofibric acid (CLA), a hypolipidaemic drug and peroxisomal proliferator, on phosphatidylethanolamine (PE) synthesis in rat liver and fatty acid metabolism. Fasting and CLA treatment of animals causes an increase in the amount of PE in endoplasmic reticulum (ER) membranes and mitochondria, as well as in the PE/phosphatidylcholine (PC) ratio. Moreover, the activity of the ethanolamine-specific phospholipid base exchange (PLBE) enzyme in liver ER membranes of fasted animals was enhanced by 75% in comparison to that of animals fed ad libitum. The effect of CLA treatment was additive to that of starvation; PE synthesis tested in vitro via the Ca2+-sensitive PLBE reaction increased 3-fold in comparison to rats fed ad libitum. This is confirmed by an increased Vmax for the reaction, but the affinity of the enzyme for ethanolamine was not significantly changed. These effects were accompanied by an enhanced expression of cytochrome P450 CYP4A1 isoform and elevated activity of the enzyme upon CLA administration. The stimulatory effect of CLA administration on the efficiency of the ethanolamine-specific PLBE reaction can be explained by elimination of lauric acid, a known inhibitor of de novo PE synthesis, during the course of omega-hydroxylation catalysed by CYP4A1, and by increased expression of the PLBE enzyme. The products of omega-hydroxylation of lauric acid, which are then converted by dehydrogenase to 1,12-dodecanedioic acid, did not significantly affect the in vitro synthesis of PE.


Assuntos
Ácido Clofíbrico/administração & dosagem , Sistema Enzimático do Citocromo P-450/metabolismo , Hipolipemiantes/administração & dosagem , Microssomos Hepáticos/metabolismo , Fosfatidiletanolaminas/biossíntese , Animais , Dieta , Ativação Enzimática/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar
8.
Acta Biochim Pol ; 45(1): 119-26, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9701504

RESUMO

Administration of a hypolipidaemic drug, clofibrate, to rats resulted, 24 h after a single intraperitoneal injection (250 mg/kg body weight), in pronounced enhancement of the rate of phosphatidylethanolamine (PE) synthesis via the PE-specific base exchange (PEBE) reaction in liver microsomes. This was accompanied by 3.4-fold activation of microsomal omega-hydroxylation of lauric acid by cytochrome P450 4A1 isoform (CYP4A1) and an increase in the protein content of this isoform in endoplasmic reticulum (ER) membranes. Since PE represents a class of phospholipids (PL) prerequisite for proper functioning of CYP4A1, and the PEBE reaction is an inducible pathway of PL synthesis in hepatocytes under metabolic stress, one may speculate that this reaction is switched on when extensive remodelling of PL molecular species or/and massive synthesis of lipid bilayer components for membrane assembly is required.


Assuntos
Clofibrato/farmacologia , Sistema Enzimático do Citocromo P-450/biossíntese , Hipolipemiantes/farmacologia , Microssomos Hepáticos/efeitos dos fármacos , Oxigenases de Função Mista/biossíntese , Fosfatidiletanolaminas/biossíntese , Animais , Citocromo P-450 CYP4A , Indução Enzimática , Masculino , Microssomos Hepáticos/metabolismo , Ratos , Ratos Wistar
9.
Mol Cell Biochem ; 168(1-2): 163-76, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9062906

RESUMO

Properties of Ca(2+)-stimulated incorporation of amincalcohols, serine and ethanolamine, into phospholipids, and factors regulating the reaction were studied in endoplasmic reticulum membranes isolated from rat liver. In contrast to apparent K(m) values for either aminoalcohol, maximal velocities of the reaction were significantly affected by Ca2+ concentration. No competition between these two soluble substrates used at equimolar concentrations close to their K(m) values was observed, suggesting the existence of two distinct phospholipid base exchange activities. The enzyme utilizing the electrically neutral serine was not sensitive to changes of membrane potential evoked by valinomycin in the presence of KCl. On the other hand, when positively charged ethanolamine served as a substrate, the enzyme activity was inhibited by 140 mM KCl and this effect was reversed by valinomycin. The rates of inhibition of phospholipid base exchange reactions by various thiol group modifying reagents were also found to differ. Cd2+ and lipophylic p-chloromercuribenzoic acid at micromolar concentrations were most effective. It can be suggested that -SH groups located within the hydrophobic core of the enzymes molecules are essential for the recognition of membrane substrates. However, the influence of the -SH group modifying reagents on the protein-facilitated phospholipid motion across endoplasmic reticulum membranes can not be excluded, since an integral protein-mediated transverse movement of phospholipids within the membrane bilayer and Ca(2+)-mediated changes in configuration of the phospholipid polar head groups seem to be a regulatory step of the reaction. Indeed, when the membrane integrity was disordered by detergents or an organic solvent, the reaction was inhibited, although not due to the transport of its water-soluble substrates is affected, but due to modulation of physical state of the membrane bilayer and, in consequence, the accessibility of phospholipid molecules.


Assuntos
Membranas Intracelulares/metabolismo , Microssomos Hepáticos/metabolismo , Fosfatidiletanolaminas/metabolismo , Animais , Transporte Biológico , Cálcio/metabolismo , Cinética , Masculino , Ratos , Ratos Wistar , Serina/metabolismo , Reagentes de Sulfidrila/química
10.
FEBS Lett ; 386(1): 33-8, 1996 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-8635598

RESUMO

In the present study the relationship between lipid peroxidation, changes in the redox state of membrane and phosphatidylethanolamine (PE) synthesis via base exchange reaction in rat liver microsomes was investigated. It was found that PE synthesis is enhanced in the presence of antioxidants, butylated hydroxytoluene (BHT), or unsaturated free fatty acids. Prooxidants, tert-butyl hydroxyperoxide (BHP), ferrous ions combined with ascorbate or NADPH (via cytochrome P450-dependent proteins), increased the amount of lipid peroxidation products in the membrane, and in consequence inhibited the reaction. The effect of BHP was fully reversed by reduced glutathione and dithiothreitol (DTT), whereas the effect of other compounds could be reversed only by BHT. In contrast, a reversal of the inhibitory effect of cadmium ions on base exchange activity was observed in the presence of DTT, but not BHT. Therefore, both the -SH/-S-S- ratio in the membrane, affected by BHP and cadmium ions, and the lipid hydroxyperoxides (rather than aldehydes), generated by ferrous ions and ascorbate or NADPH, are equally responsible for the inactivation of the ethanolamine base exchange enzyme in rat liver microsomes. This may suggest that the synthesis of PE via the base exchange reaction may be considered an element of the superfine cellular machinery involved in the repair of damage to unsaturated fatty acid chains of phospholipids caused by reactive oxygen species under oxidative stress.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Etanolaminas/metabolismo , Peroxidação de Lipídeos , Microssomos Hepáticos/metabolismo , Fosfatidiletanolaminas/biossíntese , Animais , Membrana Celular/metabolismo , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/ultraestrutura , Etanolamina , Ácidos Graxos/metabolismo , Feminino , Masculino , Mercaptoetanol/farmacologia , NADP/metabolismo , Oxirredução , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
11.
J Pediatr Health Care ; 5(6): 299-305, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1748925

RESUMO

Forty Cambodian women in Seattle, Washington were interviewed to learn about their childrearing knowledge, beliefs, practices, and information resources. It was found that women who once relied on family and elders for advice now turned to pediatric providers and other clinic staff. Most women reported accurately the ages at which developmental milestones occur, with the exception of vision and hearing milestones. Their treatment of common childhood illnesses included both Western and Cambodian remedies. Beliefs about children's nature, discipline, learning, and reincarnation were explored. Implications for providers trying to support the parenting efforts of Cambodian women in the United States are discussed.


Assuntos
Educação Infantil/etnologia , Conhecimentos, Atitudes e Prática em Saúde , Refugiados/psicologia , Adulto , Camboja/etnologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Inquéritos e Questionários , Washington
13.
J Pediatr Health Care ; 3(6): 327-8, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2593076
15.
World Health Forum ; 9(3): 454-60, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3252845

RESUMO

PIP: In Indonesia a country comprised of 13,677 islands with a 1984 population of 160 million where 1/2 are less than 20 years old, there are about 300 ethnic groups. A program, called the Family Welfare Movement was implemented to improve family welfare and health care. The Movement had only lay woman members as field representatives who were trained in health nutrition, home projects, and agriculture with a large emphasis on community service and identity. The Movement was used in this study as a platform for a potential health program in the US for people who had cultural difficulties incorporating themselves into US welfare programs. Exploratory data was gained using 88 interviews of Movement members over a 6 week period using different settings, participant observation, and examinations of documents and newspapers. Both passive and active participation in the Movement by the authors were used with the aforementioned data, which was then analyzed in chosen interconnecting categories (i.e. showing initiative, encouraging teamwork, effective leadership, and community participation). After data classification, analysis was undertaken to identify different characteristics which led to similar results, or 1 characteristic that caused different results. Recurrent themes were those identified as societal organization, role of women, cooperation and community self-help, leadership of the Family Welfare Movement, village health workers, and motivational factors in the Movement. Culture bound findings were not used in the application of the Movement to describe how one can create a similar program in the US. The conclusions were: Motivation of sharing and enjoying group activities to bring about communal togetherness could be tried on families living in isolation; volunteerism could be implemented in appropriate US areas; a hierarchical structure with role expectations could be tried on ethnic groups comfortable with hierarchical structuring; and a program concerned with all aspects of individual and family life, from agricultural to health and hygiene should be implemented.^ieng


Assuntos
Serviços de Saúde da Criança , Países em Desenvolvimento , Serviços de Saúde Materna , Criança , Feminino , Educação em Saúde , Humanos , Indonésia , Apoio Social , Estados Unidos
16.
Vet Med (Praha) ; 32(12): 705-9, 1987 Dec.
Artigo em Eslovaco | MEDLINE | ID: mdl-3127979

RESUMO

In experiments with calves during the milk-nutrition period we tested the use of the colonisation preparation Amylastim, containing a bacterial strain of Streptococcus bovis AO 24/85, as a factor speeding up the development of the rumen microflora. We gave the preparation to the animals for a period of four weeks and studied its influence on the microflora adherent to the epithelium of the rumen wall. We ascertained a significant increase in the number of Streptococcus bovis germs (P less than 0.001) as well as of alpha-amylase activity (P less than 0.05). When giving the preparation Amylastim to calves in large-scale production conditions we ascertained a positive effect on the health condition, total losses being lower.


Assuntos
Proteínas de Bactérias/administração & dosagem , Rúmen/microbiologia , Ovinos/microbiologia , Streptococcus/crescimento & desenvolvimento , Animais , Streptococcus/metabolismo , alfa-Amilases/biossíntese
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