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PubMed2006

Protective effects of carotenoids from saffron on neuronal injury in vitro and in vivo.

Crocus sativus L. (saffron) has been used as a spice for flavoring and coloring food preparations, and in Chinese traditional medicine as an anodyne or tranquilizer. Our previous study demonstrated that crocin, a carotenoid pigment of saffron, can suppress the serum deprivation-induced death of PC12 cells by increasing glutathione (GSH) synthesis and thus inhibiting neutral sphingomyelinase (nSMase) activity and ceramide formation. The carotenoid pigments of saffron consist of crocetin di-(beta-d-glucosyl)-ester [dicrocin], crocetin-(beta-d-gentiobiosyl)-(beta-d-glucosyl)-ester [tricrocin] and crocetin-di-(beta-d-gentiobiosyl)-ester [crocin]. Saffron also contains picrocrocin, the substance causing saffron's bitter taste. In this study, to confirm whether neuroprotective effects of saffron are caused solely by crocin, we examined the antioxidant and GSH-synthetic activities of these crocins in PC12 cells under serum-free and hypoxic conditions. Measurements of cell viability, peroxidized membrane lipids and caspase-3 activity showed that the rank order of the neuroprotective potency at a concentration of 10 muM was crocin>tricrocin>dicrocin and picrocrocin (the latter two crocins had a little or no potency). In addition, we show that among these saffron's constituents, crocin most effectively promotes mRNA expression of gamma-glutamylcysteinyl synthase (gamma-GCS), which contributes to GSH synthesis as the rate-limiting enzyme, and that the carotenoid can significantly reduce infarcted areas caused by occlusion of the middle cerebral artery (MCA) in mice.

Animals↗
PubMed1999

Use of fiber interface direct mass spectrometry for the determination of volatile flavor release from model food systems.

Described in this paper is a fiber interface direct headspace mass spectrometric system for the real-time measurement of flavor release. The system was optimized for the detection of the garlic aroma volatile, diallyl disulfide, from water. Parameters investigated included interface temperature, flow rate through the fiber, flow rate through the sample vessel, and sample stir rate. The delay time for detection of sample after introduction into the sample vessel was determined as 43 s. The system proved to be reliable and robust with no loss in sensitivity or contamination of the mass spectrometer over a 6 month period. The technique was applied to a homologous series of aliphatic alcohols from C(2) to C(7). Results showed that as polarity decreased with increasing chain length the release of volatile into the headspace was faster and gave a higher maximum intensity. Release of the garlic aroma volatile from different commercial mayonnaise products clearly showed a decrease in the release of diallyl disulfide as fat content increased. These results demonstrate the potential of using this technique as a tool for understanding the complex interactions that occur between flavor compounds and the bulk food matrix.

Alcohols↗
PubMed1996

Decreased hedonic responsiveness following chronic mild stress is not secondary to loss of body weight.

Chronic exposure to mild unpredictable stress (CMS) has previously been found to decrease hedonic responsiveness, as measured by the consumption of palatable sweet solutions or sensitivity to brain stimulation reward. These effects are reversed by chronic treatment with antidepressant drugs, and the CMS procedure has been proposed as a relatively valid animal model of depression. It has recently been suggested that the behavioural effects of CMS may be secondary to loss of body weight. This article collates data from five laboratories using the CMS procedure. Data are presented from seven studies using five different rat strains, as well as CD1 mice. Three-week exposure to CMS significantly decreased sucrose consumption by Lister hooded, PVG hooded, Wistar, and Wistar WU rats, and by CD1 mice, and sensitivity to brain stimulation reward in Ibm:Ro Ro rats. Weight loss in different experiments varied between 0 and 10%. Hedonic sensitivity relative to body weight (e.g., mg sucrose/g body weight) decreased significantly in all experiments. Animals maintained on a restricted feeding regime lost weight but did not show decreases in sucrose intake. It is concluded that decreased hedonic sensitivity following chronic mild stress cannot be attributed to loss of body weight.

Animals↗
PubMed2003

Behavioral and cardiovascular changes in the chronic mild stress model of depression.

Depression is a multifaceted psychological disorder that involves changes in behavior, neuroendocrine function, and physiological responses. The present study investigated multiple behavioral and cardiovascular consequences in the chronic mild stress (CMS) rodent model of depression. Rats were exposed to 4 weeks of CMS followed by 4 weeks of a stress-free recovery period. Sucrose intake, a measure of anhedonia, and spontaneous locomotor activity were measured weekly throughout the study, and cardiovascular function tests were conducted at the completion of the protocol. The results indicate that CMS results in anhedonia and reduced locomotor activity, as well as elevated heart rate (HR), reduced HR variability, and elevated sympathetic cardiac tone. The behavioral effects of CMS recovered to baseline (prestress) levels during the recovery period; however, cardiovascular changes were observed following the recovery of sucrose intake and activity levels. The present findings suggest that behavioral changes that are indicative of anhedonia and locomotor alterations associated with depression are dissociable from long-term cardiovascular changes induced by CMS.

Adrenergic beta-Antagonists↗
PubMed2002

Glucagon-like peptide-1 receptor stimulation increases blood pressure and heart rate and activates autonomic regulatory neurons.

Glucagon-like peptide-1 (GLP-1) released from the gut functions as an incretin that stimulates insulin secretion. GLP-1 is also a brain neuropeptide that controls feeding and drinking behavior and gastric emptying and elicits neuroendocrine responses including development of conditioned taste aversion. Although GLP-1 receptor (GLP-1R) agonists are under development for the treatment of diabetes, GLP-1 administration may increase blood pressure and heart rate in vivo. We report here that centrally and peripherally administered GLP-1R agonists dose-dependently increased blood pressure and heart rate. GLP-1R activation induced c-fos expression in the adrenal medulla and neurons in autonomic control sites in the rat brain, including medullary catecholamine neurons providing input to sympathetic preganglionic neurons. Furthermore, GLP-1R agonists rapidly activated tyrosine hydroxylase transcription in brainstem catecholamine neurons. These findings suggest that the central GLP-1 system represents a regulator of sympathetic outflow leading to downstream activation of cardiovascular responses in vivo.

Adrenal Glands↗
PubMed2003

Isolation of chromosaponin I-specific antibody by affinity chromatography.

Chromosaponin I (CSI), a gamma-pyronyl-triterpenoid saponin isolated from pea and other leguminous plants, modulates several developmental processes of plant roots and activates the sugar taste receptor cells in blowflies. CSI is a unique saponin for its reducing power and biological activities in both plants and insects. In the present paper, we described the method of preparation for CSI-specific antibody using CSI-affinity and soyasaponin I-affinity columns. The antibody's-specific binding activity to CSI was confirmed by a bioassay using Arabidopsis roots and a ligand-molecule interaction analysis using BIAcore 3000. Because of the lability of CSI, the CSI-affinity column was made only by a moderate reaction condition in which CSI was coupled to EAH Sepharose 4B in the presence of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC). The special control of the reaction temperature was essential to complete the coupling reaction; the reaction with EDC at 0 degrees C followed by a gradual increase in temperature.

Antibodies↗
PubMed2003

Sex differences in fruit and vegetable intake in older adults.

Fruits and vegetables are important components of a healthy diet, but intakes in most Western countries are well below the recommended five servings a day. Men in particular are eating too little. The aim of this study is to understand the processes underlying this gender difference. Fruit and vegetable intake, nutrition knowledge, taste preferences, attitudes to fruit and vegetable intake, and dieting status, were assessed in a simple questionnaire in 1,024 older adults attending population-based cancer screening across the UK. The results confirmed the pattern of men consuming fewer servings of fruit and vegetables daily than women (2.52 vs 3.47; p<0.01). Fewer men than women knew the current recommendations for fruit and vegetable intake, and fewer were aware of the links between fruit and vegetable consumption and disease prevention. Women rated their liking for vegetables but not fruit higher, and there were no differences in attitudes. Men were less likely to be dieting to lose weight. Multivariate analysis showed that the gender difference in intake was substantially attenuated by controlling for nutrition knowledge. There were no significant attenuating effects of preferences, attitudes or dieting status. These results indicate that men's poorer nutrition knowledge explains a significant part of their lower intake of fruit and vegetables.

Diet↗
PubMed2004

Sensory systems in amphioxus: a window on the ancestral chordate condition.

Amphioxus has an assortment of cells and organs for sensing light and mechanical stimuli. Vertebrate counterparts of these structures are not always apparent, and a strong case can be made for homology in only a few instances. For example, amphioxus has anatomically simple but plausible homologs of both the pineal and paired eyes of vertebrates. Placodal and neural crest derivatives are, however, more problematic: the evidence for an olfactory system in amphioxus is only circumstantial and, despite the variety of secondary sensory cell types that occur on the body surface in amphioxus, none are obvious homologs of vertebrate taste buds, neuromasts or acoustic hair cells. A useful perspective can nevertheless be gained by examining differences in amphioxus and vertebrate development, specifically how each specifies and positions sensory precursors, controls their proliferation, and deploys them through the body. The much larger size of vertebrate embryos and the need to cope developmentally with increased scale and cell numbers may account for some key vertebrate innovations, including placodes and neural crest. The presence or absence of specific structural adaptations, like the latter, is therefore less useful for judging homology between amphioxus and vertebrates than shared features of specific cell types. It is also clear that the duration of embryogenesis in vertebrates has been significantly extended in comparison with ancestral chordates so as to incorporate events that would originally have occurred during the post-embryonic growth period, including events of neurogenesis. Consequently, no scenario for the origin of vertebrates can be considered complete unless it deals explicitly with the whole of the life history and changes to it.

Animals↗
PubMed2002

Effects of long-term moderate alcohol consumption on agonistic and affiliative behavior of socially housed female cynomolgus monkeys (Macaca fascicularis).

RATIONALE: The most widely used drug in the US is alcohol. Most people who use alcohol are light-to-moderate drinkers. One or two drinks/day is thought to be not only safe but potentially health-promoting. However, little is known about the chronic effects of moderate alcohol consumption. Alcohol, even in moderate doses, has immediate and robust effects on behavior. OBJECTIVE: To determine the effects of long-term moderate alcohol consumption on the social interactions of adult monkeys. METHODS: Forty-nine adult, ovariectomized monkeys lived in small, stable social groups for 31 months and voluntarily consumed a 2-drink/day equivalent (0.5 g/kg ethanol), 5 days/week for 24 months. Alcohol was presented in a sweet tasting non-nutritive vehicle to half the monkeys, while the other half received vehicle plus maltose-dextrin isocalorically substituted for alcohol. Social behavior was recorded 1 h before, 1 h after, and 5 h after alcohol. RESULTS: Alcohol caused chronic changes in aggressive and affiliative behavior that were not dependent upon the presence of circulating alcohol. Alcohol increased physical aggression. A subset of the animals was at higher risk for alcohol-induced physical aggression. Alcohol decreased positive affiliative behaviors, increased time spent alone, and increased the frequency of extragroup vigilance. Acutely, alcohol increased the rate of behavioral pathology, i.e. stereotypic behaviors, such as hair plucking, which are normally observed only under adverse environmental conditions. CONCLUSIONS: Long-term moderate alcohol consumption caused chronic deleterious changes in the social interactions of primates in small, stable social groups. These data suggest that chronic moderate alcohol consumption can compromise optimal social interactions in primate species, including human beings.

Aggression↗
PubMed2005

Release of nucleotides and nucleosides during yeast autolysis: kinetics and potential impact on flavor.

Nucleotides, particularly 5'-nucleotides, are important flavoring agents found in many foods and beverages. Their precise effect on the flavor of wines aged on lees has not been examined previously. In this study nucleotides and nucleosides released by yeast during autolysis in a model wine system and in Champagne wines were identified and quantified, and their impact on wine flavor was determined. Ribonucleotides only were detected in yeast autolysate and in Champagne wines. In wines ribonucleotides were quantified by tandem mass spectrometry coupled to HPLC. The maximum concentration of total nucleotides was very low with a maximum of approximately 3 mg/L in wine aged on yeasts for 9 years. In young wines the most important nucleotide was 5'-UMP, but after 2 years of aging its concentration decreased and the concentration of 5'-GMP slowly increased. The threshold values of the most representative nucleotides in Champagne wines were higher than the concentrations found in the same wines. However, it is known that there is synergism between the different nucleotides and also in the presence of glutamic acid. This phenomenon could explain the difference observed in descriptive profiles of wines spiked with nucleotides.

DNA, Fungal↗
PubMed2003

Effect of sire on mu- and m-calpain activity and rate of tenderization as indicated by myofibril fragmentation indices of steaks from Brahman cattle.

The objectives of this study were to assess the influence of sire on mu- and m-calpain activities, to evaluate the relationships of activities of these enzymes to other traits related to beef palatability, and to assess the influence of sire on the rate of tenderization (as measured by myofibril fragmentation index [MFI]) in Brahman longissimus muscle. Brahman calves (n = 87), sired by nine bulls, were born, weaned, fed, and slaughtered in central Florida. Traits evaluated were mu- and m-calpain activities and MFI after 1, 7, 14, and 21 d of aging. Other traits were analyzed to determine their associations with mu- and m-calpain activity and MFI, including calpastatin activity, percentage of raw and cooked lipids, Warner-Bratzler shear force (WBSF) values after 7, 14, and 21 d of aging, and sensory panel rating of tenderness, juiciness, and connective tissue amount after 14 d of aging. Data were analyzed using a model with sire, sex, year, and slaughter group (calves of the same sex slaughtered on the same date) as fixed effects, and adjusted to a constant adjusted 12th-rib fat thickness. Sire affected mu-calpain activity (P < 0.04), calpastatin activity (P < 0.01), d-14 MFI (P < 0.02), d-7 WBSF (P < 0.05), d-14 WBSF (P < 0.04), and sensory panel juiciness score (P < 0.01), but not (P < 0.75) m-calpain activity. Measures of tenderness and palatability were generally moderately to strongly correlated (both simple and residual correlations) with calpastatin and m-calpain activity. Myofibril fragmentation index residuals (adjusted for all model components except sire) after all aging periods were fitted using nonlinear regression to the exponential curve (MFI(i) = kappa0 + kappa1 exp[kappa2 t(i)] + epsilon(i), where t(i) represents aging in days, k0 is ultimate MFI after aging, kappa1 is the difference between initial and ultimate MFI, kappa2 is the rate of increase in MFI, and epsilon(i) is the error term associated with the ith observation, assumed to be independent and identically distributed normally). Sires had different estimates and combinations of estimates, which were used to plot MFI change with time. These curves visually differed for sires and suggested that postmortem tenderization extent and rate differ as well. Use of a combination of these estimated parameters in a selection/carcass sorting program represents an alternative consideration for tenderization improvement programs.

Animals↗
PubMed2006

Bone morphogenetic proteins and noggin: inhibiting and inducing fungiform taste papilla development.

Fungiform papillae are epithelial specializations that develop in a linear pattern on the anterior mammalian tongue and differentiate to eventually contain taste buds. Little is known about morphogenetic and pattern regulation of these crucial taste organs. We used embryonic rat tongue, organ cultures to test roles for bone morphogenetic proteins, BMP2, 4 and 7, and antagonists noggin and follistatin, in development of papillae from a stage before morphological initiation (E13) or from a stage after the pre-papilla placodes have formed (E14). BMPs and noggin proteins become progressively restricted to papilla locations during tongue development. In E13 cultures, exogenous BMPs or noggin induce increased numbers of fungiform papillae, in a concentration-dependent manner, compared to standard tongue cultures; BMPs, but not noggin, lead to a decreased tongue size at this stage. In E14 cultures, however, exogenous BMP2, 4 or 7 each inhibits papilla formation so that there is a decrease in papilla number. Noggin substantially increases number of papillae in E14 cultures. Using beads for a highly localized protein delivery, papillae are inhibited in the surround of BMP-soaked beads and induced in large clusters around noggin-soaked beads. Follistatin, presented in culture medium or by bead, does not alter papilla formation or number. In all fungiform papillae that form under various culture conditions, the molecular marker, sonic hedgehog, is within each papilla. However, the BMP inhibitory effect on papillae is not prevented by disrupting sonic hedgehog signaling through addition of cyclopamine to cultures. BMPs and noggin alter cell proliferation in tongue epithelium in opposite ways, demonstrated with Ki67 immunostaining. We propose that the BMPs and noggin, colocalized within papilla placodes and the fungiform papillae per se, have opposing inhibitory and activating or inducing roles in papilla development in linear patterns. We present a model for these effects.

Animals↗
PubMed1999

Production of sulfur flavors by ten strains of Geotrichum candidum.

Ten strains of Geotrichum candidum were studied on a liquid cheese model medium for the production of sulfur compounds which contribute to the aroma of cheeses. The volatile components produced by each cultured strain were extracted by dynamic headspace extractions, separated and quantified by gas chromatography (GC), and identified by GC-mass spectrometry. It was shown that four strains of this microorganism produced significant quantities of S-methyl thioacetate, S-methyl thiopropionate, S-methyl thiobutanoate, S-methyl thioisobutanoate, S-methyl thioisovalerate, and S-methyl thiohexanoate. This is the first example of the production of these compounds by a fungus. In addition, dimethyldisulfide, dimethyltrisulfide, dimethylsulfide, and methanethiol, which are more commonly associated with the development of cheese flavor in bacterial cultures, were also produced by G. candidum in various yields, depending on the strain selected. The potential application of these strains in cultured microbial associations to produce modified cheeses with more desirable organoleptic properties is discussed.

Cheese↗
PubMed2006

Sensory correlation of glucose levels in a starch-based semi-solid model system before and after alpha-amylase breakdown.

In this study a diabetic glucose monitor was used to measure the glucose content of 40 model vanilla custard desserts, these were compared with sensory ratings from a trained quantitative descriptive analysis panel. Stimuli varied in starch type, concentration and homogenisation but had identical sugar, flavour and fat contents. Despite this, mean sensory ratings of sweetness varied from 21 to 43 on a 100-point scale. Glucose levels in the stimuli were measured, in vitro, before and after the addition of 0.1% whole human saliva to the product. In all cases glucose concentration increased after the addition of saliva as starch was converted to glucose. There were highly significant correlations of some odour, flavour, mouth feel and after-feel attributes with glucose concentration. The correlation of sweet flavour with glucose concentration was higher in unmodified stimuli than in stimuli with added saliva, suggesting that sweetness is perceived soon after ingestion. Additional glucose produced through starch breakdown appeared to have a relatively small impact on the sensory scores of the stimuli.

Adult↗
PubMedDate not supplied

Anaphylactic shock in neuropsychoimmunological research.

Anaphylaxis appears to be an excellent experimental model for investigating the interactions between central nervous system (CNS) and immune system. Both afferent and efferent regulatory pathways of anaphylactic response are well characterized. The potent mediators of anaphylactic shock, such as histamine and serotonin, are at the same time neurotransmitters, acting in the CNS, and regulators/modulators of the immune system, since receptors for these substances exist on the membrane of the cells of the immune system. In this article the results of studies on the relationship between anaphylaxis and CNS, performed by both pioneers and contemporary investigators, are briefly reviewed. Recent experiments done in our laboratory are presented, which showed that (a) anaphylactic shock can be induced by intracerebroventricular administration of the shocking dose of antigen; (b) rats can learn to associate the induction of anaphylactic shock with neutral stimuli from the environment; and (c) stress in the form of electric tail-shocks reduces the intensity of anaphylactic shock.

Anaphylaxis↗
PubMed1994

Dose response of chlorhexidine against plaque and comparison with triclosan.

The optimum dose of chlorhexidine delivered by mouthrinse, which balances efficacy against local side-effects, is generally considered to be in the region of 20 mg 2 x daily. Unfortunately, there have been few dose-response studies for chlorhexidine mouthrinses and for these, only limited details are published. The aims of this study were to determine the dose response of chlorhexidine to plaque inhibition and position a 0.1% triclosan rinse within this model. 28 subjects took part in this 7-treatment, double-blind, randomised cross-over 4-day plaque regrowth study. The rinses were 0.01%, 0.05%, 0.1% and 0.2% chlorhexidine, 0.1% triclosan and minus active controls for chlorhexidine and triclosan. On day 1 from a zero plaque baseline, volunteers suspended tooth-cleaning and commenced supervised 2 x daily rinsing with 10 ml volumes of the allocated rinses. On Day 5, plaque was scored by index and area. Treatment differences between the 7 rinses were highly significant. A clear dose-response pattern was seen for chlorhexidine with mean plaque scores decreasing with increasing dose. Even at 0.01%, chlorhexidine showed considerable and significant plaque inhibition compared to control. Triclosan at 0.1% showed limited plaque inhibition and less than 0.01% chlorhexidine. The findings of this study suggest that consideration could be given to low concentration chlorhexidine rinses as adjuncts to oral hygiene.

Adult↗
PubMed1987

The effects of excitotoxic lesions of the substantia innominata, ventral and dorsal globus pallidus on the acquisition and retention of a conditional visual discrimination: implications for cholinergic hypotheses of learning and memory.

The effects of ibotenic acid-induced lesions of the ventral pallidum/substantia innominata region, the dorsal pallidum or both on the acquisition and retention of a conditional visual discrimination have been studied in the rat. Lesions of the ventral pallidum and large lesions of the dorsal and ventral pallidum severely impaired both the acquisition and retention of the conditional discrimination. Dorsal pallidal lesions had similar, but less marked effects. The same lesions also impaired the retention of a passive avoidance task, but had no effect on a conditioned taste aversion. Neurobiological investigations revealed that the lesions destroyed cholinergic neurons in the magnocellular nucleus basalis and caused reductions in cortical choline acetyltransferase activity of about 30-40%. Tract-tracing experiments indicated that the lesions destroyed, in particular, cholinergic neurons projecting to the frontal dorsolateral cortex and also those projecting to more posterior cortex, but not the occipital lobes. Contingency analysis of the behavioural, neurochemical and neuroanatomical data indicated that those animals with the largest decreases in choline acetyltransferase activity, or the largest areas of neuronal loss in the ventral and dorsal globus pallidus, were most impaired in the retention of the conditional discrimination. The results do not, therefore, indicate a simple relationship between cholinergic neuronal loss and the retention of response rules essential for performance of the task ("reference memory"). The relevance of the results to cholinergic hypotheses of learning and memory is discussed.

Animals↗
PubMed2003

Moth chemosensory protein exhibits drastic conformational changes and cooperativity on ligand binding.

Chemosensory proteins (CSPs) have been proposed to transport hydrophobic chemicals from air to olfactory or taste receptors. They have been isolated from several sensory organs of a wide range of insect species. The x-ray structure of CSPMbraA6, a 112-aa antennal protein from the moth Mamestra brassicae (Mbra), was shown to exhibit a novel type of alpha-helical fold. We have performed a structural and binding study of CSPMbraA6 to get some insights into its possible molecular function. Tryptophan fluorescence quenching demonstrates the ability of CSPMbraA6 to bind several types of semio-chemicals or surrogate ligands with microM K(d). Its crystal structure in complex with one of these compounds, 12-bromo-dodecanol, reveals extensive conformational changes on binding, resulting in the formation of a large cavity filled by three ligand molecules. Furthermore, binding cooperativity was demonstrated for some ligands, suggesting a stepwise binding. The peculiar rearrangement of CSPMbraA6 conformation and the cooperativity phenomenon might trigger the recognition of chemicals by receptors and induce subsequent signal transduction.

Animals↗