RESUMEN
Gastropod molluscs are among the most abundant species that inhabit coral reef ecosystems. Many are specialist predators, along with the giant triton snail Charonia tritonis (Linnaeus, 1758) whose diet consists of Acanthaster planci (crown-of-thorns starfish), a corallivore known to consume enormous quantities of reef-building coral. C. tritonis are considered vulnerable due to overexploitation, and a decline in their populations is believed to have contributed to recurring A. planci population outbreaks. Aquaculture is considered one approach that could help restore natural populations of C. tritonis and mitigate coral loss; however, numerous questions remain unanswered regarding their life cycle, including the molecular factors that regulate their reproduction and development. In this study, we have established a reference C. tritonis transcriptome derived from developmental stages (embryo and veliger) and adult tissues. This was used to identify genes associated with cell signalling, such as neuropeptides and G protein-coupled receptors (GPCRs), involved in endocrine and olfactory signalling. A comparison of developmental stages showed that several neuropeptide precursors are exclusively expressed in post-hatch veligers and functional analysis found that FFamide stimulated a significant (20.3%) increase in larval heart rate. GPCRs unique to veligers, and a diversity of rhodopsin-like GPCRs located within adult cephalic tentacles, all represent candidate olfactory receptors. In addition, the cytochrome P450 superfamily, which participates in the biosynthesis and degradation of steroid hormones and lipids, was also found to be expanded with at least 91 genes annotated, mostly in gill tissue. These findings further progress our understanding of C. tritonis with possible application in developing aquaculture methods.
Asunto(s)
Caracoles/genética , Caracoles/metabolismo , Transcriptoma , Animales , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Larva/genética , Larva/metabolismo , Neuropéptidos/genética , Neuropéptidos/metabolismo , Receptores Acoplados a Proteínas G/genética , Caracoles/crecimiento & desarrolloRESUMEN
BACKGROUND: Chemosensation is a critical signalling process for all organisms and is achieved through the interaction between chemosensory receptors and their ligands. The Crown-of-thorns starfish, Acanthaster planci species complex (COTS), is a predator of coral polyps and Acanthaster cf. solaris is currently considered to be one of the main drivers of coral loss on the Great Barrier Reef in Queensland, Australia. RESULTS: This study reveals the presence of putative variant Ionotropic Receptors (IRs) which are differentially expressed in the olfactory organs of COTS. Several other types of G protein-coupled receptors such as adrenergic, metabotropic glutamate, cholecystokinin, trace-amine associated, GRL101 and GPCR52 receptors have also been identified. Several receptors display male-biased expression within the sensory tentacles, indicating possible reproductive significance. CONCLUSIONS: Many of the receptors identified in this study may have a role in reproduction and are therefore key targets for further investigation. Based on their differential expression within the olfactory organs and presence in multiple tissues, it is possible that several of these receptor types have expanded within the Echinoderm lineage. Many are likely to be species-specific with novel ligand-binding affinity and a diverse range of functions. This study is the first to describe the presence of variant Ionotropic Glutamate Receptors in any Echinoderm, and is only the second study to investigate chemosensory receptors in any starfish or marine pest. These results represent a significant step forward in understanding the chemosensory abilities of COTS.
Asunto(s)
Perfilación de la Expresión Génica , Proteínas de Insectos/genética , Receptores de Superficie Celular/genética , Órganos de los Sentidos/metabolismo , Estrellas de Mar/genética , Animales , Femenino , Proteínas de Insectos/metabolismo , Funciones de Verosimilitud , Masculino , Filogenia , Receptores de Superficie Celular/metabolismoRESUMEN
The symbiotic relationship between corals and Symbiodinium spp. is the key to the success and survival of coral reef ecosystems the world over. Nutrient exchange and chemical communication between the two partners provides the foundation of this key relationship, yet we are far from a complete understanding of these processes. This is due, in part, to the difficulties associated with studying an intracellular symbiosis at the small spatial scales required to elucidate metabolic interactions between the two partners. This feasibility study, which accompanied a more extensive investigation of fixed Symbiodinium cells (data unpublished), examines the potential of using synchrotron radiation infrared microspectroscopy (SR-IRM) for exploring metabolite localisation within a single Symbiodinium cell. In doing so, three chemically distinct subcellular regions of a single Symbiodinium cell were established and correlated to cellular function based on assignment of diagnostic chemical classes.
Asunto(s)
Factores Biológicos/análisis , Dinoflagelados/química , Dinoflagelados/ultraestructura , Microscopía/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Estudios de FactibilidadRESUMEN
The giant triton snail (Charonia tritonis) is one of the few natural predators of the adult Crown-of-Thorns starfish (COTS), a corallivore that has been damaging to many reefs in the Indo-Pacific. Charonia species have large salivary glands (SGs) that are suspected to produce either a venom and/or sulphuric acid which can immobilize their prey and neutralize the intrinsic toxic properties of COTS. To date, there is little information on the types of toxins produced by tritons. In this paper, the predatory behaviour of the C. tritonis is described. Then, the C. tritonis SG, which itself is made up of an anterior lobe (AL) and posterior lobe (PL), was analyzed using an integrated transcriptomics and proteomics approach, to identify putative toxin- and feeding-related proteins. A de novo transcriptome database and in silico protein analysis predicts that ~3800 proteins have features consistent with being secreted. A gland-specific proteomics analysis confirmed the presence of numerous SG-AL and SG-PL proteins, including those with similarity to cysteine-rich venom proteins. Sulfuric acid biosynthesis enzymes were identified, specific to the SG-PL. Our analysis of the C. tritonis SG (AL and PL) has provided a deeper insight into the biomolecular toolkit used for predation and feeding by C. tritonis.
Asunto(s)
Genómica/métodos , Conducta Predatoria , Glándulas Salivales/metabolismo , Caracoles/genética , Estrellas de Mar/fisiología , Secuencia de Aminoácidos , Animales , Proteínas/química , Proteínas/genética , Proteómica , Glándulas Salivales/anatomía & histología , Ácidos Sulfúricos/metabolismo , TranscriptomaRESUMEN
Neuropeptides represent a diverse class of signaling molecules originating from neural tissues. These chemical modulators orchestrate complex physiological events including those associated with growth and reproduction. De novo transcriptome sequencing of a cerebral ganglion library of the endangered giant triton snail (Charonia tritonis) was undertaken in an effort to identify key neuropeptides that control or influence its physiology. The giant triton snail is considered a primary predator of the corallivore Acanthaster planci (Crown-of-Thorns Starfish) that is responsible for a significant loss in coral cover on reefs in the Indo-Pacific. The transcriptome library was assembled into contigs, and then bioinformatic analysis was used to identify a repertoire of 38 giant triton snail neuropeptide precursor genes, and various isoforms, that encode conserved molluscan neuropeptides. C. tritonis neuropeptides show overall precursor organisation consistent with those of other molluscs. These include those neuropeptides associated with mollusc reproduction such as the APGWamide, buccalin, conopressin, gonadotropin-releasing hormone (GnRH), NKY and egg-laying hormone. These data provide a foundation for further studies targeted towards the functional characterisation of neuropeptides to further understand aspects of the biology of the giant triton snail, such as elucidating its reproductive neuroendocrine pathway to allow the development of knowledge based captive breeding programs.
Asunto(s)
Neuropéptidos/genética , Caracoles/crecimiento & desarrollo , Caracoles/genética , Transcriptoma/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Simulación por Computador , Ganglios de Invertebrados/metabolismo , Estudios de Asociación Genética , Hormonas de Invertebrados/genética , Reproducción , Estrellas de MarRESUMEN
The majority of marine invertebrates produce dispersive larvae which, in order to complete their life cycles, must attach and metamorphose into benthic forms. This process, collectively referred to as settlement, is often guided by habitat-specific cues. While the sources of such cues are well known, the links between their biological activity, chemical identity, presence and quantification in situ are largely missing. Previous work on coral larval settlement in vitro has shown widespread induction by crustose coralline algae (CCA) and in particular their associated bacteria. However, we found that bacterial biofilms on CCA did not initiate ecologically realistic settlement responses in larvae of 11 hard coral species from Australia, Guam, Singapore and Japan. We instead found that algal chemical cues induce identical behavioral responses of larvae as per live CCA. We identified two classes of CCA cell wall-associated compounds--glycoglycerolipids and polysaccharides--as the main constituents of settlement inducing fractions. These algae-derived fractions induce settlement and metamorphosis at equivalent concentrations as present in CCA, both in small scale laboratory assays and under flow-through conditions, suggesting their ability to act in an ecologically relevant fashion to steer larval settlement of corals. Both compound classes were readily detected in natural samples.
Asunto(s)
Antozoos/fisiología , Animales , Bacterias , Señales (Psicología) , LarvaRESUMEN
The production of salicylihalamide A by the marine sponge Haliclona sp. was investigated. Samples of the two morphologies (green and brown) were collected from four locations covering approximately 1,200 km of coastline. Temporal variation between winter and summer was also examined at Bremer Bay. Chemical profiling by using liquid chromatography coupled with ultra violet detection and mass spectrometry showed that salicylihalamide A was produced only by the green morphology. Salicylihalamide A concentration was significantly correlated to water temperature but not to the size or depth of the sponge. Salicylihalamide A concentration was found to differ significantly among locations (Bremer Bay 13.5 microg g(-1), Hamelin Bay 11 microg g(-1), Rottnest Island 9.9 microg g(-1), and Jurien Bay 8.5 microg g(-1)) partially accounted for by the influence of water temperature. A difference between seasons was also observed in Bremer Bay (summer concentration of 13.5 microg g(-1) vs. winter concentration of 8.2 microg g(-1)). Environmental and physiological factors appear to be important in the production of salicylihalamide A by the green morphology. Additionally, the brown morphology does not produce salicylihalamide A, thus adding to the evidence that this morphology may be a different species.
Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes/metabolismo , Poríferos/metabolismo , Temperatura , Animales , Cromatografía Liquida , Espectrometría de Masas , Espectrofotometría UltravioletaRESUMEN
Homocysteine is an emerging new risk factor for cardiovascular disease. It is a thiol compound derived from methionine and involved in two main metabolic pathways: the cycle of activated methyl groups, requiring folate and vitamin B12 as cofactors, and the transsulfuration pathway to cystathionine and cysteine requiring vitamin B6 as cofactor. The homocysteine metabolism represents an interesting model of gene-environment interaction. Elevations in homocysteine may be caused by genetic defects in enzymes involved in its metabolism or by deficiencies in cofactor levels. A common polymorphism in the gene coding for the 5,10-methylene tetrahydrofolate reductase (MTHFR) (C677T, Ala --> Val) is associated with a decreased activity of the enzyme due to thermolability. In case of homozygosity for the Val allele, a relative deficiency in the remethylation process of homocysteine into methionine leads to a mild-to-moderate hyperhomocysteinemia, a condition recognized as an independent risk factor for atherosclerosis. The genetic influence of the MTHFR polymorphism on homocysteine levels is attenuated in females in premenopausal age and is not significant in subjects who exhibit serum levels of folate and/or vitamin B12 above the 50th percentile of distribution in the general population. The prevalence of the Val/Val genotype varies among different ethnic groups. It is very low in African populations, whereas in Europe and North America it ranges between 5% and 15%. In Italy an even higher prevalence has been reported in some regions. The question whether the MTHFR polymorphism might be per se an independent contributor to cardiovascular risk is debated. The interaction between this or other genetic factors and environmental/nutritional conditions (i.e. intake of vitamins such as folate) is a key determinant for homocysteine concentrations in healthy conditions as well as in some disease (i.e. in renal disorders). Another example of gene/environment interaction in the field of atherosclerosis is given by the apolipoprotein E polymorphism and its influence in response to diet. The presence of a high prevalence of risk-related allelic variants of such candidate genes within a certain population could serve to locally reinforce the recommendations concerning nutrient intake.
Asunto(s)
Enfermedades Cardiovasculares/genética , Homocisteína/sangre , Hiperhomocisteinemia/complicaciones , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/genética , Apolipoproteínas E/genética , Arteriosclerosis/etiología , Arteriosclerosis/genética , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/etiología , Genotipo , Humanos , Enfermedades Renales/etiología , Enfermedades Renales/genética , Metilenotetrahidrofolato Reductasa (NADPH2) , Mutación , Polimorfismo Genético , Prevalencia , Factores de RiesgoRESUMEN
Paraoxonase (PON) is a high-density lipoprotein (HDL) associated protein which is supposed to protect low-density lipoprotein (LDL) against oxidation and to play a role in the development of atherosclerosis. Interindividual variability in serum PON activity is attributable to common variants in components of the PON gene cluster on chromosome 7. We describe experimental conditions that permit the simultaneous determination of three common PON polymorphisms (PON1-192, PON1-55 and PON2-311) that are tightly associated with an increased risk of atherosclerosis. We used a multiplex PCR-based DNA assay using mismatch primers that introduce a unique recognition site for the endonuclease HinfI in the PCR products in case of presence of the R allele of PON 1-192, of the L allele of PON1-55 and of the S allele of PON2-311. The restriction analysis with HinfI allows to identify an electrophoretic band pattern which is specific for the combination of the three polymorphisms. This technique could be applied in the association studies aimed at assessing the role of PON and their polymorphisms in many clinical settings. In a preliminary study on a small population sample from south Italy about 10% of chromosomes exhibited the presumed risk-related haplotype R(192)/L(55)/S(311).
Asunto(s)
Arteriosclerosis/genética , Esterasas/genética , Polimorfismo Genético , Alelos , Arteriosclerosis/enzimología , Arildialquilfosfatasa , Cromosomas Humanos Par 7 , Esterasas/sangre , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , Factores de RiesgoRESUMEN
We have observed two ABCA1 gene transcripts in human skin fibroblasts. The RT-PCR amplification of the exon 3-exon 8 region generated a normal fragment (740 bp) and an abnormal fragment (600 bp) in a ratio ranging from 3:1 to 8/9:1. These two transcripts were present in other cells such as leukemia T-cells, endothelial and smooth muscle cells as well human hepatoma cells (HepG2). Restriction enzyme analysis and sequencing indicated that in the abnormal fragment exon 3 was followed by exon 5. The complete skipping of exon 4 leads to a premature stop and a predicted translation product of 74 amino acids. The ratio between the normal and alternative transcript is not affected by variation in ABCA1 gene expression induced by incubating cells in serum-free medium and in the presence of cholesterol. It is possible that this alternative splicing represents as mechanism that regulates the ABCA1 content in tissues.
Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Empalme Alternativo , Transportador 1 de Casete de Unión a ATP , Secuencia de Aminoácidos , Secuencia de Bases , Análisis Mutacional de ADN , Cartilla de ADN/genética , ADN Complementario/genética , Exones , Fibroblastos/metabolismo , Expresión Génica , Humanos , Intrones , Lipoproteínas HDL/deficiencia , Lipoproteínas HDL/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Piel/metabolismoRESUMEN
Wall shear stress contributes to the endothelial production of vasoactive mediators, like nitric oxide (NO). Brachial artery vasodilation that follows increased blood flow is regulated by NO release. Aim of the present study was to investigate whether resting wall shear stress of the brachial artery is related to flow-mediated vasodilation (FMD) induced by forearm ischemia. Wall shear stress was calculated according to the following formula: Wall shear stress=Blood viscosity x Blood velocity/Internal diameter. FMD was calculated as percentage change of brachial artery diameter following forearm ischemia. Twenty-seven healthy male subjects were investigated. Peak wall shear stress and FMD were 37.3+/-12.8 dynes/cm(2) and 110.7+/-5.6%, respectively (mean+/-S.D.). In simple regression analyses, age was inversely associated with wall shear stress (r=48, P<0.01) and, marginally, with FMD (r=0.33, P=0.08). Wall shear stress and FMD were directly related (r=0.60, P<0.001). In multiple regression analysis, including wall shear stress, age, blood pressure, lipids, glucose and Body Mass Index as independent variables, wall shear stress was the only variable independently associated with FMD (standardized beta coefficient=0.690, P
Asunto(s)
Arteria Braquial/fisiología , Vasodilatación/fisiología , Adulto , Anciano , Viscosidad Sanguínea/fisiología , Arteria Braquial/fisiopatología , Antebrazo/irrigación sanguínea , Humanos , Isquemia/fisiopatología , Masculino , Persona de Mediana Edad , Valores de Referencia , Flujo Sanguíneo Regional/fisiología , Estrés MecánicoRESUMEN
Seventy-one mutations of the low density lipoprotein (LDL) receptor gene were identified in 282 unrelated Italian familial hypercholesterolemia (FH) heterozygotes. By extending genotype analysis to families of the index cases, we identified 12 mutation clusters and localized them in specific areas of Italy. To evaluate the impact of these mutations on the clinical expression of FH, the clusters were separated into 2 groups: receptor-defective and receptor-negative, according to the LDL receptor defect caused by each mutation. These 2 groups were comparable in terms of the patients' age, sex distribution, body mass index, arterial hypertension, and smoking status. In receptor-negative subjects, LDL cholesterol was higher (+18%) and high density lipoprotein cholesterol lower (-5%) than the values found in receptor-defective subjects. The prevalence of tendon xanthomas and coronary artery disease (CAD) was 2-fold higher in receptor-negative subjects. In patients >30 years of age in both groups, the presence of CAD was related to age, arterial hypertension, previous smoking, and LDL cholesterol level. Independent contributors to CAD in the receptor-defective subjects were male sex, arterial hypertension, and LDL cholesterol level; in the receptor-negative subjects, the first 2 variables were strong predictors of CAD, whereas the LDL cholesterol level had a lower impact than in receptor-defective subjects. Overall, in receptor-negative subjects, the risk of CAD was 2.6-fold that of receptor-defective subjects. Wide interindividual variability in LDL cholesterol levels was found in each cluster. Apolipoprotein E genotype analysis showed a lowering effect of the epsilon2 allele and a raising effect of the epsilon4 allele on the LDL cholesterol level in both groups; however, the apolipoprotein E genotype accounted for only 4% of the variation in LDL cholesterol. Haplotype analysis showed that all families of the major clusters shared the same intragenic haplotype cosegregating with the mutation, thus suggesting the presence of common ancestors.
Asunto(s)
Hiperlipoproteinemia Tipo II/genética , Receptores de LDL/genética , Adulto , LDL-Colesterol/metabolismo , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/genética , Enfermedad Coronaria/metabolismo , Femenino , Variación Genética , Haplotipos , Humanos , Hiperlipoproteinemia Tipo II/epidemiología , Hiperlipoproteinemia Tipo II/metabolismo , Italia , Masculino , Familia de Multigenes , Mutación , Fenotipo , PrevalenciaRESUMEN
We assessed the contribution of the serum homocysteine (Hcy) level, an independent risk factor for vascular disease, and methylene tetrahydrofolate reductase (MTHFR) gene polymorphism to the variability of intimal-medial thickness (IMT) of the common carotid artery in middle-aged non-insulin-dependent diabetes mellitus (NIDDM) subjects. One hundred thirty NIDDM patients (60 males and 70 females) with a mean age of 53 +/- 10 years and a mean diabetes duration of 11.3 +/- 7.9 years were enrolled for the study. Exclusion criteria included liver, heart, kidney, or other major-organ disease. Fasting total serum Hcy, folate, and vitamin B12 and clinical chemistry analyte levels were measured. MTHFR polymorphism was determined by polymerase chain reaction (PCR). IMT and plaques or stenosis in the common carotid were measured by ultrasonography. Serum Hcy was inversely correlated with vitamin levels and was slightly higher in subjects with the Val/Val genotype versus Ala/Val and Ala/Ala (P = .02); no differences in genotype were found in subjects with folate or vitamin B12 at or above the median level. In univariate analysis, common carotid IMT was significantly associated with age (P = .00001), the body mass index ([BMI] P = .0003), uric acid (P = .004), systolic blood pressure (P = .03), glycemia (P = .03), and total cholesterol (P = .04). No significant association was found between serum Hcy or MTHFR polymorphism and IMT. In multiple regression analysis, age (P = .0001), uric acid (P = .03), glycemia, and the BMI (P = .05) were independently associated with IMT and explained about 42% of IMT variability. In 130 NIDDM patients without nephropathy, basal levels of serum Hcy, as well as MTHFR polymorphism, did not predict significant changes in common carotid IMT.
Asunto(s)
Arterias Carótidas/enzimología , Diabetes Mellitus Tipo 2/enzimología , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/genética , Túnica Íntima/patología , Arteriosclerosis/sangre , Arteriosclerosis/genética , Estenosis Carotídea/patología , Diabetes Mellitus Tipo 2/genética , Femenino , Genotipo , Humanos , Italia , Masculino , Metilenotetrahidrofolato Reductasa (NADPH2) , Persona de Mediana Edad , Polimorfismo de Nucleótido SimpleRESUMEN
The results of the large trials with the inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase (or statins) in terms of clinical benefits in patients with coronary artery disease indicate that these drugs act in a complex way on several pathways involved in the atherosclerotic process. Beyond their lipid-lowering activity, statins appear to modify many characteristics of the arterial wall, resulting in protection against the progression of plaque growth and/or the precipitation of acute events. The so called "pleiotropic" effects of statins, such as the restoration of endothelial activity, the antioxidant potential or the antiproliferative effect on smooth muscle cells, have been investigated mainly in in vitro experiments. In the near future, it will be necessary to unravel the biological significance and the clinical relevance of these effects, which also involve other pathological conditions such as cancer and osteoporosis. Furthermore, lessons from the trials with statins have allowed a better understanding of the mechanisms leading to atherosclerosis which is now considered as an inflammatory process affecting the vascular wall. This has opened new perspectives in the search for the development of newer and more targeted anti-atherogenic drugs.
Asunto(s)
Arteriosclerosis/tratamiento farmacológico , Ácidos Heptanoicos/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hipolipemiantes/uso terapéutico , Lovastatina/uso terapéutico , Pravastatina/uso terapéutico , Pirroles/uso terapéutico , Atorvastatina , Ensayos Clínicos como Asunto , Ácidos Heptanoicos/farmacología , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Hipolipemiantes/farmacología , Lovastatina/farmacología , Pravastatina/farmacología , Pirroles/farmacología , Simvastatina/farmacología , Simvastatina/uso terapéuticoRESUMEN
The inhibitors of 3-hydroxy-3-methylglutaryl-CoA reductase (or statins) are the most powerful drugs affecting lipid and lipoprotein levels in plasma. Results obtained from large controlled trials using simvastatin, pravastatin and lovastatin for the primary or secondary prevention of coronary heart disease have demonstrated that treatment with statins is associated with a significant reduction in coronary morbidity and mortality and in total mortality. This is probably due to a more general anti-atherogenic effect of these drugs beyond their lipid-lowering activity. Meta-analysis of data from these large trials indicates that statins have an impact also on the incidence of cerebrovascular events. Currently, six statins have been approved for therapeutic use in different countries. In spite of the similarities in their chemical structure and mechanisms of action, statins may differ in many aspects such as pharmacological properties (hydrophilic vs lipophilic, elimination half-life, cytochrome P450 metabolism, etc.), effects on lipid and other biochemical variables, or pleiotropic effects on different metabolic processes related to atherosclerosis (endothelial function, platelet aggregation, immune function, etc.). In general, the safety and tolerability profile for all statins currently in use is good with a < 2% incidence of undesirable effects.
Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Hipolipemiantes/farmacología , Naftalenos/farmacología , Atorvastatina , Enfermedad Coronaria/tratamiento farmacológico , Enfermedad Coronaria/mortalidad , Ácidos Grasos Monoinsaturados/efectos adversos , Ácidos Grasos Monoinsaturados/farmacología , Ácidos Grasos Monoinsaturados/uso terapéutico , Fluvastatina , Ácidos Heptanoicos/efectos adversos , Ácidos Heptanoicos/farmacología , Ácidos Heptanoicos/uso terapéutico , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hipolipemiantes/efectos adversos , Hipolipemiantes/uso terapéutico , Indoles/efectos adversos , Indoles/farmacología , Indoles/uso terapéutico , Lípidos/sangre , Lovastatina/efectos adversos , Lovastatina/farmacología , Lovastatina/uso terapéutico , Naftalenos/efectos adversos , Naftalenos/uso terapéutico , Pravastatina/efectos adversos , Pravastatina/farmacología , Pravastatina/uso terapéutico , Piridinas/efectos adversos , Piridinas/farmacología , Piridinas/uso terapéutico , Pirroles/efectos adversos , Pirroles/farmacología , Pirroles/uso terapéutico , Simvastatina/efectos adversos , Simvastatina/farmacología , Simvastatina/uso terapéuticoRESUMEN
A common variant in the promoter of the human stromelysin gene, causing reduced enzyme expression, has been associated with the progression of coronary atherosclerosis. On the other hand, increased stromelysin activity may promote plaque rupture. The present study was undertaken to investigate the relationship between the genetic variation in the human stromelysin gene promoter and common carotid geometry. Forty-two healthy male subjects without major coronary heart disease risk factors were investigated. The polymorphism in the stromelysin gene promoter was studied through polymerase chain reaction amplification with the use of mutagenic primers. Age, blood pressure, lipids, glucose, viscosity, and body mass index were similar in homozygotes for the 5A allele (5A/5A), heterozygotes (5A/6A), and homozygotes for the 6A allele (6A/6A). Serum matrix metalloproteinase-3 levels did not differ significantly among genotypes. Common carotid diameters and intima-media thickness, measured by noninvasive ultrasonography, were significantly larger in 6A/6A subjects (for respective 6A/6A, 5A/6A, and 5A/5A subjects, diameter at the R wave was 0.63+/-0.09, 0.55+/-0.06, and 0.53+/-0.04 cm [mean+/-SD], P<0.005 by ANOVA; intima-media thickness was 765+/-116, 670+/-116, and 630+/-92 microm [mean+/-SD], P<0.05 by ANOVA). Wall shear stress, calculated as blood velocityxblood viscosity/internal diameter, was significantly lower in 6A/6A subjects (for respective 6A/6A, 5A/6A, and 5A/5A subjects, mean wall shear stress was 10.4+/-2.9, 13.5+/-3.5, and 12.6+/-1.9 dyne/cm(2) [mean+/-SD], P<0.05 by ANOVA). The results demonstrate that the gene polymorphism in the promoter region of stromelysin is associated with structural and functional characteristics of the common carotid artery in healthy male subjects without major risk factors for atherosclerosis. Individuals with the 6A/6A genotype (associated with lower enzyme activity) show a triad of events, namely, increased wall thickness, enlarged arterial lumen, and local reduction of wall shear stress, which might predispose them to atherosclerotic plaque localization.
Asunto(s)
Arteria Carótida Común/diagnóstico por imagen , Variación Genética , Metaloproteinasa 3 de la Matriz/genética , Regiones Promotoras Genéticas , Adulto , Alelos , Arteriosclerosis/genética , Velocidad del Flujo Sanguíneo , Glucemia/análisis , Presión Sanguínea , Hemorreología , Heterocigoto , Homocigoto , Humanos , Lípidos/sangre , Masculino , Metaloproteinasa 3 de la Matriz/sangre , Persona de Mediana Edad , Polimorfismo Genético , Factores de Riesgo , UltrasonografíaAsunto(s)
Diabetes Mellitus Tipo 2/genética , Homocisteína/sangre , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/genética , Adulto , Diabetes Mellitus Tipo 2/sangre , Femenino , Frecuencia de los Genes , Humanos , Hiperglucemia/sangre , Hiperglucemia/genética , Masculino , Metilenotetrahidrofolato Reductasa (NADPH2) , Persona de Mediana Edad , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/sangre , Valores de ReferenciaRESUMEN
Glutathione S-transferases (GSTs, EC 2.5.1.18) belong to a large family of functionally different enzymes that catalyze the S-conjugation of glutathione with a wide variety of electrophilic compounds including carcinogens and anticancer drugs. Drug resistance may result from reduction in apoptosis of neoplastic cells when exposed to antineoplastic drugs. The c-Jun N-terminal Kinase (JNK) belongs to the family of stress kinases and has been shown to be required for the maximal induction of apoptosis by DNA-damaging agents. Recently, an inhibition of JNK activity by GST P1-1, which was reversed by polymerization induced by oxidative stress, has been reported in 3T3-4A mouse fibroblast cell lines. The finding that GST P1-1 might inhibit JNK activity and that it is frequently highly expressed in tumor tissues suggests its possible implication in "apoptosis resistance" during antineoplastic therapy. We investigated the modulation of GST P1-1 during apoptosis in a neoplastic T-cell line (Jurkat) induced by hydrogen peroxide and etoposide. Apoptosis was paralleled by the appearance of a dimeric form of GST P1-1 on western blotting, associated with an increase in the Km(GSH) and a reduction in GST P1-1 specific activity toward 1-chloro-2,4-dinitrobenzene, which reached statistical significance only in H(2)O(2)-treated cells. Our data seem to suggest that H(2)O(2) and etoposide may partly act through a process of partial inactivation of the GST P1-1, possibly involving the "G" site in the process of dimerization, and thus favoring programmed cell death.