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1.
Plant Foods Hum Nutr ; 79(1): 151-158, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38231454

RESUMO

Amaranth, quinoa, and buckwheat are the representatives of pseudocereals, different parts and by-products of which are used in daily nutrition and food processing industry. However, only scarce information exists on the bioactivity of their oils. Thus, oils obtained from amaranth, buckwheat, and red, yellow, and white quinoa seeds were evaluated in terms of their nutritional (fatty acid profile, squalene), cytotoxic (against normal and neoplastic gastrointestinal, prostate, and skin cells), anti-inflammatory and antiradical (interleukin 6, TNF-alpha, nitric oxide, DPPH, Total phenolics, and superoxide dismutase) potential in the in vitro model. Linoleic (42.9-52.5%) and oleic (22.5-31.1%) acids were the two main unsaturated, while palmitic acid (4.9-18.6%) was the major saturated fatty acid in all evaluated oils. Squalene was identified in all evaluated oils with the highest content in amaranth oil (7.6 g/100 g), and the lowest in buckwheat oil (2.1 g/100 g). The evaluated oils exerted a high direct cytotoxic impact on cancer cells of different origins, but also revealed anti-inflammatory and antiradical potentials. Yellow quinoa oil was the most active, especially toward skin (A375; IC50 6.3 µg/mL), gastrointestinal (HT29 IC50 4.9 µg/mL), and prostate cancer cells (LNCaP IC50 7.6 µg/mL). The observed differences in the activity between the oils from the tested quinoa varieties deserve further studies. High selectivity of the oils was noted, which indicates their safety to normal cells. The obtained results indicate that the oils are good candidates for functional foods with perspective chemopreventive potential.


Assuntos
Sementes , Esqualeno , Esqualeno/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Sementes/química , Ácidos Graxos/análise , Óleos de Plantas/análise , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/análise
2.
Molecules ; 28(16)2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37630288

RESUMO

Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1H NMR) spectroscopies were applied to characterize and compare the chemical shifts in the polyphenols' regions of some fruit wines. The obtained results showed that FTIR spectra (1800-900 cm-1) and 1H NMR (δ 6.5-9.3 ppm) of different fruit wines can be used as main indices of the year of vintage and quality of fruit wines. In addition to the classical determination of antioxidant profiles and bioactive substances in wines, fluorometric measurements were used to determine the interactions of wine substances with the main human serum proteins. The results showed relatively high binding properties of wines with the highest one for pomegranate, followed by kiwifruit and persimmon wines. The interactions of vitamin C, catechin and gallic acid with human serum albumin (HSA) were also examined by docking studies. The docking calculations showed that gallic acid has a stronger binding affinity compared to catechin and vitamin C. The stronger binding affinity of gallic acid may be due to three hydrogen bonds and pi-pi interactions. The fluorescence and docking studies proved that only the bioactive compounds of wines and not the amount of alcohol have high binding properties to human serum proteins. The emphasis in this report was made on the utility of FTIR, NMR and fluorescence of wines as a mean of wine authentication and its fingerprint. The findings, based on polyphenols from fruits and fruit wines, their bioactivity and health properties, offer valuable insights for future endeavours focused on designing healthy food products.


Assuntos
Catequina , Vinho , Humanos , Frutas , Análise de Fourier , Espectroscopia de Infravermelho com Transformada de Fourier , Ácido Ascórbico , Vitaminas , Espectroscopia de Ressonância Magnética
3.
Int J Mol Sci ; 23(7)2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35409366

RESUMO

Bufalin and other cardiac steroids (CS) have been used for centuries for the treatment of congestive heart failure, arrhythmias, and other maladies. However, toxicity and the small therapeutic window of this family of steroids limit their use. Therefore, attempts to synthesize a potent, but less toxic, CS are of major importance. In the present study, two novel bufalin derivatives were synthesized and some of their pharmacological properties were characterized. The reaction of bufalin with Ishikawa's reagent resulted in the production of two novel bufalin derivatives: bufalin 2,3-ene and bufalin 3,4-ene. The compounds were purified with TLC and HPLC and their structure was verified with UV, NMR, and MS analyses. The biological activities of these compounds were evaluated by testing their ability to inhibit the Na+, K+-ATPase activity of the brain microsomal fraction to induce cytotoxic activity against the NCI-60 human tumor cell line panel and non-cancer human cells, and to increase the force of contraction of quail embryonic heart muscle cells in culture. The two steroids exhibited biological activities similar to those of other CS in the tested experimental systems, but with reduced cytotoxicity, advocating their development as drugs for the treatment of heart failure and arrhythmias.


Assuntos
Bufanolídeos , Ouabaína , Arritmias Cardíacas/tratamento farmacológico , Bufanolídeos/metabolismo , Bufanolídeos/farmacologia , Humanos , Microssomos/metabolismo , Ouabaína/farmacologia , ATPase Trocadora de Sódio-Potássio/metabolismo
4.
Molecules ; 26(21)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34771095

RESUMO

Previous reports have shown that consumption of wine has several health benefits; however, there are different types of wine. In the present study, red wines were investigated for their compositions of active ingredients. The interaction of each component in terms of its binding mode with different serum proteins was unraveled, and the components were implicated as drug candidates in clinical settings. Overall, the study indicates that red wines have a composition of flavonoids, non-flavonoids, and phenolic acids that can interact with the key regions of proteins to enhance their biological activity. Among them, rutin, resveratrol, and tannic acid have shown good binding affinity and possess beneficial properties that can enhance their role in clinical applications.


Assuntos
Biomarcadores/sangue , Proteínas Sanguíneas/antagonistas & inibidores , Flavonoides/farmacologia , Vinho/análise , Bebidas Alcoólicas , Antioxidantes/análise , Sítios de Ligação , Proteínas Sanguíneas/química , Proteínas Sanguíneas/metabolismo , Flavonoides/química , Flavonoides/farmacocinética , Fluorometria/métodos , Humanos , Ligantes , Modelos Moleculares , Conformação Molecular , Fenóis , Ligação Proteica , Relação Estrutura-Atividade , Vinho/efeitos adversos
5.
Molecules ; 25(21)2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33120936

RESUMO

Our recently published in vivo studies and growing evidence suggest that moderate consumption of beer possesses several health benefits, including antioxidant and cardiovascular effects. Although beer contains phenolic acids and flavonoids as the major composition, and upon consumption, the levels of major components increase in the blood, there is no report on how these beer components interact with main human serum proteins. Thus, to address the interaction potential between beer components and human serum proteins, the present study primarily aims to investigate the components of beer from different industrial sources as well as their mode of interaction through in silico analysis. The contents of the bioactive compounds, antioxidant capacities and their influence on binding properties of the main serum proteins in human metabolism (human serum albumin (HSA), plasma circulation fibrinogen (PCF), C-reactive protein (CRP) and glutathione peroxidase 3 (GPX3)) were studied. In vitro and in silico studies indicated that phenolic substances presented in beer interact with the key regions of the proteins to enhance their antioxidant and health properties. We hypothesize that moderate consumption of beer could be beneficial for patients suffering from coronary artery disease (CAD) and other health advantages by regulating the serum proteins.


Assuntos
Cerveja/análise , Proteínas Sanguíneas/metabolismo , Simulação por Computador , Saúde , Fenóis/análise , Fenóis/metabolismo , Antioxidantes/análise , Antioxidantes/metabolismo , Proteínas Sanguíneas/química , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Conformação Proteica
6.
Bipolar Disord ; 18(5): 451-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27393337

RESUMO

OBJECTIVES: Bipolar disorder (BD) is a complex psychiatric disorder characterized by mania and depression. Alterations in brain Na(+) , K(+) -ATPase and cardiac steroids (CSs) have been detected in BD, raising the hypothesis of their involvement in this pathology. The present study investigated the behavioral and biochemical consequences of a reduction in endogenous brain CS activity in animal models of mania. METHODS: Amphetamine (AMPH)-induced hyperactivity in BALB/c and black Swiss mice served as a model of mania. Behavior was evaluated in the open-field test in naïve mice or in mice treated with anti-ouabain antibodies. CS levels were determined by enzyme-linked immunosorbent assay (ELISA), using sensitive and specific anti-ouabain antibodies. Extracellular signal-regulated kinase (ERK) and protein kinase B (Akt) phosphorylation levels in the frontal cortex were determined by western blot analysis. RESULTS: Administration of AMPH to BALB/c and black Swiss mice resulted in a marked increase in locomotor activity, accompanied by a threefold increase in brain CSs. The lowering of brain CSs by the administration of anti-ouabain antibodies prevented the hyperactivity and the increase in brain CS levels. AMPH caused an increase in phosphorylated ERK (p-ERK) and phosphorylated Akt (p-Akt) levels in the frontal cortex, which was significantly reduced by administration of the antibodies. A synthetic 'functional antagonist' of CSs, 4-(3'α-15'ß-dihydroxy-5'ß-estran-17'ß-yl) furan-2-methyl alcohol, also resulted in attenuation of AMPH-induced hyperactivity. CONCLUSIONS: These results are in accordance with the notion that malfunctioning of the Na(+) , K(+) -ATPase/CS system may be involved in the manifestation of mania and identify this system as a potential new target for drug development.


Assuntos
Comportamento Animal , Transtorno Bipolar/metabolismo , Lobo Frontal , Ouabaína/imunologia , Animais , Anticorpos/farmacologia , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Transtorno Bipolar/terapia , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática/métodos , Lobo Frontal/enzimologia , Lobo Frontal/metabolismo , Camundongos , Fosforilação/fisiologia
7.
BMC Genomics ; 17: 451, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27295982

RESUMO

BACKGROUND: The application of genotyping by sequencing (GBS) approaches, combined with data imputation methodologies, is narrowing the genetic knowledge gap between major and understudied, minor crops. GBS is an excellent tool to characterize the genomic structure of recently domesticated (~200 years) and understudied species, such as cranberry (Vaccinium macrocarpon Ait.), by generating large numbers of markers for genomic studies such as genetic mapping. RESULTS: We identified 10842 potentially mappable single nucleotide polymorphisms (SNPs) in a cranberry pseudo-testcross population wherein 5477 SNPs and 211 short sequence repeats (SSRs) were used to construct a high density linkage map in cranberry of which a total of 4849 markers were mapped. Recombination frequency, linkage disequilibrium (LD), and segregation distortion at the genomic level in the parental and integrated linkage maps were characterized for first time in cranberry. SSR markers, used as the backbone in the map, revealed high collinearity with previously published linkage maps. The 4849 point map consisted of twelve linkage groups spanning 1112 cM, which anchored 2381 nuclear scaffolds accounting for ~13 Mb of the estimated 470 Mb cranberry genome. Bin mapping identified 592 and 672 unique bins in the parentals and a total of 1676 unique marker positions in the integrated map. Synteny analyses comparing the order of anchored cranberry scaffolds to their homologous positions in kiwifruit, grape, and coffee genomes provided initial evidence of homology between cranberry and closely related species. CONCLUSIONS: GBS data was used to rapidly saturate the cranberry genome with markers in a pseudo-testcross population. Collinearity between the present saturated genetic map and previous cranberry SSR maps suggests that the SNP locations represent accurate marker order and chromosome structure of the cranberry genome. SNPs greatly improved current marker genome coverage, which allowed for genome-wide structure investigations such as segregation distortion, recombination, linkage disequilibrium, and synteny analyses. In the future, GBS can be used to accelerate cranberry molecular breeding through QTL mapping and genome-wide association studies (GWAS).


Assuntos
Mapeamento Cromossômico , Ligação Genética , Genoma de Planta , Genômica , Genótipo , Vaccinium macrocarpon/genética , Análise por Conglomerados , Genômica/métodos , Desequilíbrio de Ligação , Repetições de Microssatélites , Polimorfismo de Nucleotídeo Único , Sintenia
8.
J Am Osteopath Assoc ; 115(7): 444-50, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26111132

RESUMO

BACKGROUND: The Joint Commission requires hospitals to develop systems in which a team of clinicians can rapidly recognize and respond to changes in a patient's condition. The rapid response team (RRT) concept has been widely adopted as the solution to this mandate. The role of house staff in RRTs and the impact on resident education has been controversial. At Christiana Care Health System, eligible residents in their second through final years lead the RRTs. OBJECTIVE: To evaluate the use of a team-based, interdisciplinary RRT training program for educating and training first-year residents in an effort to improve global RRT performance before residents start their second year. METHODS: This pilot study was administered in 3 phases. Phase 1 provided residents with classroom-based didactic sessions using case-based RRT scenarios. Multiple choice examinations were administered, as well as a confidence survey based on a Likert scale before and after phase 1 of the program. Phase 2 involved experiential training in which residents engaged as mentored participants in actual RRT calls. A qualitative survey was used to measure perceived program effectiveness after phase 2. In phase 3, led by senior residents, simulated RRTs using medical mannequins were conducted. Participants were divided into 5 teams, in which each resident would rotate in the roles of leader, nurse, and respiratory therapist. This phase measured resident performance with regard to medical decision making, data gathering, and team behaviors during the simulated RRT scenarios. Performance was scored by an attending and a senior resident. RESULTS: A total of 18 residents were eligible (N=18) for participation. The average multiple choice test score improved by 20% after didactic training. The average confidence survey score before training was 3.44 out of 5 (69%) and after training was 4.13 (83%), indicating a 14% improvement. High-quality team behaviors correlated with medical decision making (0.92) more closely than did high-quality data gathering (0.11). This difference narrowed during high-pressure scenarios (0.84 and 0.72, respectively). CONCLUSION: Our data suggest that resident training using a team-based, interdisciplinary RRT training program may improve resident education, interdisciplinary team-based dynamics, and global RRT performance. In turn, data gathering and medical decision making may be enhanced, which may result in better patient outcomes during RRT scenarios.


Assuntos
Serviços Médicos de Emergência/normas , Internato e Residência/normas , Equipe de Assistência ao Paciente/organização & administração , Avaliação de Programas e Projetos de Saúde , Ensino/normas , Competência Clínica , Educação Médica Continuada/normas , Avaliação Educacional , Humanos , Projetos Piloto
9.
Clin Proteomics ; 11(1): 42, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25838813

RESUMO

BACKGROUND: Pancreatic cysts are being increasingly identified in patients. Mucinous cysts have malignant potential whereas non-mucinous cysts do not. Distinguishing potentially malignant cysts from harmless ones by the characterization of cyst fluid contents remains a difficult problem. This study was undertaken to determine whether cyst fluid mucin glycoprotein analysis could differentiate mucinous from non-mucinous pancreatic cysts. METHODS: Cyst fluid from 28 patients who underwent resection of a pancreatic cyst was used for the study. In each case the type of cyst was histologically identified. One dimensional SDS polyacrylamide gel electrophoresis (1D-SDS PAGE) was performed on cyst fluid samples. For the detection of the separated proteins, we employed a novel dual staining technique. The gel was first stained with periodic acid Schiff (PAS), a mucin histochemical stain followed by a secondary protein staining with Simply Blue Safestain (Invitrogen). RESULTS: Visual scoring (based on the presence of mucins) gave a sensitivity of 95%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 88% for prediction of mucinous histology. CONCLUSIONS: One dimensional SDS polyacrylamide gel electrophoresis of pancreatic cyst fluid, followed by mucin (PAS) and protein (Simply Blue Safestain) staining, provides a means of concentrating and visualizing mucins, which allows the accurate differentiation of mucinous from non-mucinous histology in pancreatic cysts.

10.
Isr J Health Policy Res ; 2(1): 49, 2013 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-24351209

RESUMO

BACKGROUND: This paper examines whether individuals facing the threat of poverty are curtailing their consumption of various goods and services in a given order and, if among the expenditures that are cut back, there are also health expenditures. The location of individuals in this order of cutback is then used to derive the degree of their deprivation and the factors that affect the extent of this deprivation. METHODS: This order of curtailment of expenditures is obtained on the basis of an algorithm originally devised to derive the order of acquisition of durable goods. Having found the order of curtailment of expenditures on the basis of the 2003 Israel Social Survey, we then estimate an ordered logit regression whose latent dependent variable is assumed to measure the individual degree of deprivation. RESULTS: The results of this estimation show that, other things constant, the individual latent level of deprivation increases with the size of the household, first increases and then decreases with the age of the individual, is higher when the individual has children under the age of five, has a low educational level, a low income, and when he/she is separated or divorced. Finally, deprivation is found to be lower among individuals with good health. CONCLUSION: Discovering the order of curtailment of expenditures, including health expenditures, of individuals facing economic difficulties and finding the determinants of the extent of such deprivation should help policy makers focus their attention on the population subgroups that are most likely to curtail their health expenditures when facing economic difficulties.

11.
Neurochem Res ; 37(7): 1490-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22422289

RESUMO

Brain lipid metabolism was studied in rats following permanent bilateral common carotid artery ligation (BCCL), a model for chronic cerebral hypoperfusion. Unesterified (free) fatty acids (uFA) and acyl-CoA concentrations were measured 6 h, 24 h, and 7 days after BCCL or sham surgery, in high energy-microwaved brain. In BCCL compared to sham rats, cytosolic phospholipase A(2) (cPLA(2)) immunoreactivity in piriform cortex, and concentrations of total uFA and arachidonoyl-CoA, an intermediate for arachidonic acid reincorporation into phospholipids, were increased only at 6 h. At 24 h, immunoreactivity for secretory phospholipase A(2) (sPLA(2)), which may regulate blood flow, was increased near cortical and hippocampal blood vessels. BCCL did not affect levels of brain IB(4)+ microglia, glial fibrillary acidic protein (GFAP)+ astrocytes, cyclooxygenase-2 (COX-2) immunoreactivity at any time, but increased cPLA(2) immunoreactivity in one region at 6 h. Thus, BCCL affected brain lipid metabolism transiently, likely because of compensatory sPLA(2)-mediated vasodilation, without producing evidence of neuroinflammation.


Assuntos
Encéfalo/metabolismo , Artérias Carótidas/patologia , Metabolismo dos Lipídeos , Animais , Artérias Carótidas/metabolismo , Cromatografia Líquida de Alta Pressão , Ácidos Graxos/metabolismo , Imuno-Histoquímica , Masculino , Ratos , Ratos Endogâmicos WKY
12.
Am J Primatol ; 73(1): 75-83, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20084672

RESUMO

Exponential expansion of human populations and human activities within primate habitats has resulted in high potential for pathogen exchange creating challenges for biodiversity conservation and global health. Under such conditions, resilient habitat generalists such as black and gold howler monkeys (Alouatta caraya) may act as effective sentinels to overall ecosystem health and alert us to impending epidemics in the human population. To better understand this potential, we examined noninvasively collected fecal samples from black and gold howler monkeys from remote, rural, and village populations in Northern Argentina. We examined all samples (n=90) for the zoonotic protozoa Cryptosporidium sp. and Giardia sp. via immunofluorescent antibody (IFA) detection. All samples were negative for Cryptosporidium sp. The prevalence of Giardia sp. was significantly higher at the rural site (67%) compared with the remote forest (57%) and village (40%) sites. A lack of Cryptosporidium sp. in all samples examined suggests that this pathogen is not a natural component of the howler parasite communities at these sites and that current land-use patterns and livestock contact are not exposing Argentine howler monkeys to this pathogen. High prevalence of Giardia sp. at all sites suggests that howler monkeys may serve as a viable reservoir for Giardia. Significantly higher prevalence of Giardia sp. at the rural site, where primate-livestock contact is highest, suggests the presence of multiple Giardia clades or increased exposure to Giardia through repeated zoonotic transmission among nonhuman primates, livestock, and/or people. These results highlight the need for future research into the epidemiology, cross-species transmission ecology, and clinical consequences of Giardia and other infectious agents not only in humans and livestock, but also in the wild animals that share their environments.


Assuntos
Alouatta/parasitologia , Criptosporidiose/epidemiologia , Cryptosporidium/fisiologia , Ecossistema , Giardia/classificação , Giardíase/transmissão , Animais , Argentina/epidemiologia , Reservatórios de Doenças/parasitologia , Saúde Ambiental , Fezes/parasitologia , Giardia/fisiologia , Giardíase/epidemiologia , Humanos , Gado/parasitologia , Prevalência , Árvores , Zoonoses
14.
Neurochem Res ; 31(6): 759-65, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16791473

RESUMO

The in vivo rate of turnover of phosphatidylinositol (PtdIns) in brain is not known. In brain, certain receptor-mediated signal transduction involves metabolism of PtdIns and a method to measure its turnover in awake animals is useful in studying the effect of lithium and other therapeutic agents. In a method described here, rats were infused subcutaneously with myo-[2H6]inositol (Ins*) using an osmotic pump and, at 1 and 8 weeks, concentrations of free myo-inositol (Ins) and Ins* in plasma and brain were measured by GC-MS (chemical ionization). Also, PtdIns and PtdIns* together in brain were isolated, and Ins and Ins* from their headgroups were released enzymatically and specific activity of incorporated inositol was measured. The specific activity of inositol reached a steady state in plasma within 1 week of infusion, but not in brain even at 8 weeks. However, in brain, the specific activity of phosphatidylinositol was same as that of inositol at both time-points, suggestive of fast turnover of PtdIns. The animal experiment and the analytical methodology described here should be useful for measuring the rate of turnover of brain PtdIns in pathological and drug treatment conditions.


Assuntos
Encéfalo/metabolismo , Inositol/sangue , Fosfatidilinositóis/metabolismo , Animais , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Ratos , Ratos Endogâmicos F344
15.
J Med Chem ; 49(2): 600-6, 2006 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-16420045

RESUMO

The synthesis and some pharmacological properties of 4-(3'alpha-15'beta-dihydroxy-5beta-estran-17'beta-yl)furan-2-methyl alcohol (16) have been described. The compound was synthesized by reacting a synthetic 3alpha- benzyloxy-5beta-estr-15-en-17-one with the ethylene acetal of 4-bromo-2-furancarboxyaldehyde, followed by hydrolysis of the ethylene acetal and reduction of the aldehyde. Despite its resemblance to the structure of cardiac steroids (CS), 16 does not bind to the CS receptor on Na(+),K(+)-ATPase and does not increase the force of contraction of heart muscle. However, 16 inhibited the digoxin-induced increase in the force of contraction and arrhythmias in guinea pig papillary muscle and human atrial appendages. The steroid also inhibited digoxin-induced alteration in endocytosed membrane traffic, indicating a novel mechanism of action.


Assuntos
Digoxina/antagonistas & inibidores , Estranos/síntese química , Animais , Encéfalo/metabolismo , Linhagem Celular , Digoxina/metabolismo , Digoxina/farmacologia , Estranos/farmacologia , Cobaias , Humanos , Técnicas In Vitro , Contração Miocárdica/efeitos dos fármacos , Neurônios/metabolismo , Ensaio Radioligante , Sinaptossomos/metabolismo , Transferrina/biossíntese
16.
Lipids ; 40(11): 1149-54, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16459927

RESUMO

Tissues changes in FA metabolism can occur quite rapidly in response to ischemia and may require immediate microwave fixation to determine basal concentrations. The present study aimed to quantify the effects of immediate no-flow ischemia on concentrations of individual nonesterified FA (NEFA) and acyl-CoA species in the rat heart. Male CDF 344 rats were anesthetized and decapitated either 5 min prior to being microwaved (5.5 kW, 3.4 s, twice) to produce ischemia or microwaved prior to decapitation (nonischemic). Hearts were then removed and used to measure the concentrations of acyl-CoA species and FA in several lipid classes. The ischemic heart total NEFA concentration was significantly lower than that in the nonischemic heart (11.9 vs. 19.0 nmol/g). Several individual NEFA concentrations were decreased by 31-85%. Ischemic heart total long-chain acyl-CoA concentrations (21.0 nmol/g) were significantly higher than those in nonischemic hearts (11.4 nmol/g). Increased concentrations of individual acyl-CoA species occurred in palmitoyl-CoA, stearoyl-CoA, oleoyl-CoA, and linoleoyl-CoA. Concentrations of short-chain acetyl-CoA and beta-hydroxy-beta-methylglutaryl-CoA were also two- to three-fold higher in ischemic hearts than in nonischemic hearts. The FA concentration in TG and phospholipids generally did not differ between the groups. Decreases in concentrations of individual FA and increases in acyl-CoA species during no-flow ischemia occur very rapidly within the heart. Although it is not clear how these alterations contribute to the pathogenesis of ischemia, it is evident that future studies attempting to quantify basal levels of these metabolites could use microwave fixation.


Assuntos
Acil Coenzima A/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Isquemia/metabolismo , Miocárdio/metabolismo , Animais , Fosfolipídeos/metabolismo , Ratos , Triglicerídeos/metabolismo
17.
Toxicon ; 42(5): 481-90, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14529729

RESUMO

Snake venoms are a very abundant source of nerve growth factors (NGF). NGFs of Elapidae showing 65% sequence homology with mouse or human NGF, while the Viperidae NGF shows N-glycosylation (Asn-21) typical of these mammalian NGFs. Snake NGF-induced neurite outgrowth (neurotropic activity) was measured in the past by using PC12 cell or dorsal root ganglion bioassays. The present study was aimed at comparing, by dose-response experiments, the neurotropic activity of cobra and vipera versus mammalian NGFs, by using a novel bioassay involving PC12 cells genetically engineered to overexpress NGF-trkA receptors of human origin. These cells respond to NGF by differentiation (morphologically expressed as neurite outgrowth) by a process mediated by NGF-trkA receptors. This process was evaluated by two different criteria: (1) elongation of neurites (E), and (2) Percentage of responsive cells (PRC) determined by digital acquisition of data and computer analysis. We found that snake venom NGFs were less potent than mouse NGF, and that cobra NGF was more potent than vipera NGF. These data indicate the following order of NGF activity towards recombinant human trkA receptors: recombinant human NGF>mouse NGF>cobra NGF>vipera NGF. The neurotropic efficacy of these NGFs was found to be similar, reaching 80-90% of maximal activity obtained with all NGF forms. Interestingly, cobra (but not vipera) NGF demonstrated prolonged neurotropic activity compared with mouse NGF. The results of the present study indicate that cobra and vipera venom NGFs represent natural agonists of human trkA-receptor of a lower potency, but of similar efficacy, compared with mammalian NGFs. These compounds are important pharmacological tools to characterize the trkA receptor structure-function relationship, and to develop novel neurotropic drugs.


Assuntos
Bioensaio/métodos , Venenos Elapídicos/farmacologia , Fatores de Crescimento Neural/efeitos dos fármacos , Receptor trkA/metabolismo , Venenos de Víboras/farmacologia , Animais , Relação Dose-Resposta a Droga , Humanos , Camundongos , Fatores de Crescimento Neural/isolamento & purificação , Neuritos/efeitos dos fármacos , Células PC12 , Ratos , Receptor trkA/genética , Proteínas Recombinantes/efeitos dos fármacos
18.
Neurochem Res ; 28(6): 861-6, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12718439

RESUMO

Sodium valproate and lithium are used to treat bipolar disorder. In rats, both reduce the turnover of arachidonic acid in several brain phospholipids, suggesting that arachidonate turnover is a common target of action of these mood stabilizers. However, the mechanisms by which these drugs reduce arachidonate turnover in brain are not the same. Lithium decreases turnover by reducing the activity and expression of the 85-kDa type IVA cytosolic phospholipase A2 (cPLA2); valproate does not affect cPLA2 activity or expression. To test whether valproate alters neural membrane order by direct esterification into phospholipid or by interrupting intermediary CoA metabolism, we measured valproyl-CoA, esterified valproate, and short chain acyl-CoAs in brains from control rats and rats treated chronically with sodium valproate. Valproyl-CoA and esterified forms of valproate were not found in brain with detection limits of 25 and 37.5 pmol/g brain(-1), respectively. Valproate treatment did result in a 1.4-fold decrease and 1.5-fold increase in the brain concentrations of free CoA and acetyl-CoA when compared to control. Therefore the reduction of brain arachidonic acid turnover by chronic valproate in rats is not related to the formation of valproyl-CoA or esterified valproate, but may involve changes in the intermediary metabolism of CoA and short chain acyl-CoA.


Assuntos
Acetilcoenzima A/metabolismo , Acil Coenzima A/farmacologia , Encéfalo/metabolismo , Coenzima A/metabolismo , Ácido Valproico/metabolismo , Ácido Valproico/farmacologia , Acil Coenzima A/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Cromatografia Gasosa , Ésteres , Ácidos Graxos/metabolismo , Cinética , Masculino , Metilação , Ratos , Ratos Endogâmicos F344
19.
Neurochem Res ; 27(12): 1577-82, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12515307

RESUMO

A rapid and reliable method was developed to quantify brain concentrations of coenzyme A (CoA) and short-chain acyl-CoAs having chain length < or = 4 carbon atoms. The method employs tissue extraction and isolation using an oligonucleotide purification cartridge and quantifies concentrations by peak area analysis following high-performance liquid chromatography (HPLC). In adult anesthetized rats subjected to 4-s high-energy microwave irradiation to stop brain metabolism, the brain concentrations of CoA, 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA), acetyl-CoA, and butyryl-CoA equaled 68.7 +/- 18.5, 2.7 +/- 1.5, 7.6 +/- 2.3, and 30.6 +/- 15.9 nmol x g(-1), respectively. After 5 min of complete ischemia, the brain concentrations of CoA and HMG-CoA increased 2- and 12-fold compared to controls, whereas acetyl-CoA and butyryl-CoA concentrations did not change. Markedly elevated levels of CoA and HMG-CoA following cerebral ischemia may reflect disturbed energy metabolism and altered formation of cholesterol and isoprenoids.


Assuntos
Acil Coenzima A/metabolismo , Isquemia Encefálica/metabolismo , Coenzima A/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Masculino , Ratos , Ratos Sprague-Dawley
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