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Biomedical subjects

J B German

Publications and source records attributed to J B German.

At least 19 recordsLinked to original sources
PubMed2005

Unveiling health attitudes and creating good-for-you foods: the genomics metaphor, consumer innovative web-based technologies.

This article presents an integrated analysis of three emerging knowledge bases in the nutrition and consumer products industries, and how they may effect the food industry. These knowledge bases produce new vistas for corporate product development, especially with respect to those foods that are positioned as 'good for you.' Couched within the current thinking of state-of-the-art knowledge and information, this article highlights how today's thinking about accelerated product development can be introduced into the food and health industries to complement these three research areas. The 3 knowledge bases are: the genomics revolution, which has opened new insights into understanding the interactions of personal needs of individual consumers with nutritionally relevant components of the foods; the investigation of food choice by scientific studies; the development of large scale databases (mega-studies) about the consumer mind. These knowledge bases, combined with new methods to understand the consumer through research, make possible a more focused development. The confluence of trends outlined in this article provides the corporation with the beginnings of a new path to a knowledge-based, principles-grounded product-development system. The approaches hold the potential to create foods based upon people's nutritional requirements combined with their individual preferences. Integrating these emerging knowledge areas with new consumer research techniques may well reshape how the food industry develops new products to satisfy consumer needs and wants.

Affect↗
PubMed2005

The nutritional phenotype in the age of metabolomics.

The concept of the nutritional phenotype is proposed as a defined and integrated set of genetic, proteomic, metabolomic, functional, and behavioral factors that, when measured, form the basis for assessment of human nutritional status. The nutritional phenotype integrates the effects of diet on disease/wellness and is the quantitative indication of the paths by which genes and environment exert their effects on health. Advances in technology and in fundamental biological knowledge make it possible to define and measure the nutritional phenotype accurately in a cross section of individuals with various states of health and disease. This growing base of data and knowledge could serve as a resource for all scientific disciplines involved in human health. Nutritional sciences should be a prime mover in making key decisions that include: what environmental inputs (in addition to diet) are needed; what genes/proteins/metabolites should be measured; what end-point phenotypes should be included; and what informatics tools are available to ask nutritionally relevant questions. Nutrition should be the major discipline establishing how the elements of the nutritional phenotype vary as a function of diet. Nutritional sciences should also be instrumental in linking the elements that are responsive to diet with the functional outcomes in organisms that derive from them. As the first step in this initiative, a prioritized list of genomic, proteomic, and metabolomic as well as functional and behavioral measures that defines a practically useful subset of the nutritional phenotype for use in clinical and epidemiological investigations must be developed. From this list, analytic platforms must then be identified that are capable of delivering highly quantitative data on these endpoints. This conceptualization of a nutritional phenotype provides a concrete form and substance to the recognized future of nutritional sciences as a field addressing diet, integrated metabolism, and health.

Diet↗
PubMed2004

Metabolomics in the opening decade of the 21st century: building the roads to individualized health.

It is rapidly becoming possible to measure hundreds or thousands of metabolites in small samples of biological fluids or tissues. This makes it possible to assess the metabolic component of nutritional phenotypes and will allow individualized dietary recommendations. ASNS has to take action to ensure that appropriate technologies are developed and that metabolic databases are constructed with the right inputs and organization. The relations between diet and metabolomic profiles and between those profiles and health and disease must be established. ASNS also should consider the social implications of these advances and plan for their appropriate utilization.

Animals↗
PubMed2003

The production of lipids alternately labelled with carbon-13.

Chlorella cells were shown to have similar fatty acid profiles when grown photoautotrophically or if grown photoheterotrophically with ethanoate (acetate) as carbon source. When supplied with ethanoate labelled with carbon-13 in the methyl group, the alga incorporated it into fatty acids with retention of the sequence of labelling on alternate carbon atoms, thus providing a convenient method for synthesising lipids in a form useful for nuclear magnetic resonance (NMR) studies of lipids in situ in membranes. Marine algae used in fish farming may have higher levels of very highly unsaturated fatty acids; proposals for producing these compounds labelled with carbon-13 are, therefore, presented, based on using centrally labelled glycerol. The scope for producing other substances labelled in a form suitable for NMR studies, such as carotenoids, is discussed.

Carbon Isotopes↗
PubMed2003

Concentration of polar MFGM lipids from buttermilk by microfiltration and supercritical fluid extraction.

Buttermilk contains the milk fat globule membrane (MFGM), a material that possesses many complex lipids that function as nutritionally valuable molecules. Milk-derived sphingolipids and phospholipids affect numerous cell functions, including regulating growth and development, molecular transport systems, stress responses, cross membrane trafficking, and absorption processes. We developed a two-step method to produce buttermilk derivative ingredients containing increased concentrations of the polar MFGM lipids by microfiltration and supercritical fluid extraction (SFE). These processes offer environmentally benign alternatives to conventional lipid fractionation methods that rely on toxic solvents. Firstly, using a ceramic tubular membrane with 0.8-micron pore size, we evaluated the cross flow microfiltration system that maximally concentrated the polar MFGM lipids using a 2n factorial design; the experimental factors were buttermilk source (fresh, or reconstituted from powder) and temperature (50 degrees C, and 4 degrees C). Secondly, a SFE process using supercritical carbon dioxide removed exclusively nonpolar lipid material from the microfiltered buttermilk product. Lipid analysis showed that after SFE, the product contained a significantly reduced concentration of nonpolar lipids, and a significantly increased concentration of polar lipids derived from the MFGM. Particle size analysis revealed an impact of SFE on the product structure. The efficiency of the SFE system using the microfiltration-processed powder was compared much more favorably to using buttermilk powder.

Animals↗
PubMed2002

Whey components: millennia of evolution create functionalities for mammalian nutrition: what we know and what we may be overlooking.

Nutrition is undergoing a revolution owing to the recognition that some foods contain trophic, health-promoting factors distinct from essential nutrients. In this revolution, whey is increasingly being viewed as more than a source of proteins with a particularly nutritious composition of essential amino acids. Milk evolved under continuous Darwinian selection pressure to nourish mammalian neonates. Evolutionary pressure appears to have led to the elaboration of a complex food that contains proteins, peptides, complex lipids, and oligosaccharides that act as growth factors, toxin-binding factors, antimicrobial peptides, prebiotics, and immune regulatory factors within the mammalian intestine. Importantly, these trophic macromolecules are not essential, although the health benefits that their biological activities within the intestine provide likely contributed to neonatal survival. Human and bovine milks contain many homologous components, and bovine whey may prove to be a source for molecules capable of providing biological activities to humans when consumed as food ingredients. To approach this potential, food and nutrition research must move beyond the description of food ingredients as delivering only essential nutrients and develop a mechanistic understanding of the interactions between dietary components and the metabolic and physiological properties of the intestine.

Amino Acids, Branched-Chain↗
PubMed2001

Unique phospholipid metabolism in mouse heart in response to dietary docosahexaenoic or alpha-linolenic acids.

Diet and fatty acid metabolism interact in yet unknown ways to modulate membrane fatty acid composition and certain cellular functions. For example, dietary precursors or metabolic products of n-3 fatty acid metabolism differ in their ability to modify specific membrane components. In the present study, the effect of dietary 22:6n-3 or its metabolic precursor, 18:3n-3, on the selective accumulation of 22:6n-3 by heart was investigated. The mass and fatty acid compositions of individual phospholipids (PL) in heart and liver were quantified in mice fed either 22:6n-3 (from crocodile oil) or 18:3n-3 (from soybean oil) for 13 wk. This study was conducted to determine if the selective accumulation of 22:6n-3 in heart was due to the incorporation of 22:6n-3 into cardiolipin (CL), a PL most prevalent in heart and known to accumulate 22:6n-3. Although heart was significantly enriched with 22:6n-3 relative to liver, the accumulation of 22:6n-3 by CL in heart could not quantitatively account for this difference. CL from heart did accumulate 22:6n-3, but only in mice fed preformed 22:6n-3. Diets rich in non-22:6n-3 fatty acids result in a fatty acid composition of phosphatidylcholine (PC) in heart that is unusually enriched with 22:6n-3. In this study, the mass of PC in heart was positively correlated with the enrichment of 22:6n-3 into PC. The increased mass of PC was coincident with a decrease in the mass of phosphatidylethanolamine, suggesting that 22:6n-3 induced PC synthesis by increasing phosphatidylethanolamine-N-methyltransferase activity in the heart.

Alligators and Crocodiles↗
PubMed2001

Genomics: food and nutrition.

Nutrition is traditionally a multidisciplinary field applying principles of molecular biochemistry and statistical epidemiology to integrative metabolism and population health. Genomics, with its global perspective, is now reinventing the future of human metabolic health. Creative experimental designs are addressing metabolic questions in nutrition ranging from energy regulation to aging, and from mechanisms of absorption to the interspecies molecular crosstalk of bacteria and human cells within the intestine.

Animals↗
PubMed2001

Interaction of estrogen and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) with hepatic fatty acid synthesis and metabolism of male chickens (Gallus domesticus).

This study tested the hypothesis that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) antagonizes estrogen-induced hepatic lipid synthesis and metabolism in birds. Twenty immature male chickens (Gallus domesticus) were divided evenly into four groups: (1) vehicle control; (2) estrogen alone (1.0 mg/kg estradiol cypionate injected on three consecutive days); (3) TCDD alone (50 microg/kg injected on the fourth day); and (4) a combination of the estrogen and TCDD treatments. On day 14, liver samples were collected for quantitative fatty acid analysis by capillary gas chromatography. Birds treated with estrogen alone had increased total triacylglyceride concentrations with specific increases in the Delta9 desaturase products 16:1n7, 18:1n7, 18:1n9, and 20:1n9. In addition, estrogen treatment specifically increased 22:6n3 concentrations in both triacylglycerides and phospholipids. However, these increases in Delta9 desaturase products or 22:6n3 did not occur for birds treated with estrogen in combination with TCDD. TCDD and estrogen plus TCDD treatments increased phospholipid concentrations of the diet-derived polyunsaturated fatty acids 18:2n6, 18:3n6, 20:3n6, 18:3n3, and 20:5n3, although only the estrogen plus TCDD group had significantly increased total phospholipids. In cholesterol esters, all three treatments decreased concentrations of total fatty acids, saturated fatty acids, and Delta9 desaturase products compared to the control group.

Animals↗
PubMed2001

Chocolate procyanidins decrease the leukotriene-prostacyclin ratio in humans and human aortic endothelial cells.

BACKGROUND: Polyphenolic phytochemicals inhibit vascular and inflammatory processes that contribute to disease. These effects are hypothesized to result from polyphenol-mediated alterations in cellular eicosanoid synthesis. OBJECTIVE: The objective was to determine and compare the ability of cocoa procyanidins to alter eicosanoid synthesis in human subjects and cultured human aortic endothelial cells. DESIGN: After an overnight fast, 10 healthy subjects (4 men and 6 women) consumed 37 g low-procyanidin (0.09 mg/g) and high-procyanidin (4.0 mg/g) chocolate; the treatments were separated by 1 wk. The investigation had a randomized, blinded, crossover design. Plasma samples were collected before treatment and 2 and 6 h after treatment. Eicosanoids were quantitated by enzyme immunoassay. Endothelial cells were treated in vitro with procyanidins to determine whether the effects of procyanidin in vivo were associated with procyanidin-induced alterations in endothelial cell eicosanoid synthesis. RESULTS: Relative to the effects of the low-procyanidin chocolate, high-procyanidin chocolate induced increases in plasma prostacyclin (32%; P<0.05) and decreases in plasma leukotrienes (29%; P<0.04). After the in vitro procyanidin treatments, aortic endothelial cells synthesized twice as much 6-keto-prostaglandin F(1alpha) (P<0.01) and 16% less leukotriene (P<0.05) as did control cells. The in vitro and in vivo effects of procyanidins on plasma leukotriene-prostacyclin ratios in culture medium were also comparable: decreases of 58% and 52%, respectively. CONCLUSION: Data from this short-term investigation support the concept that certain food-derived flavonoids can favorably alter eicosanoid synthesis in humans, providing a plausible hypothesis for a mechanism by which they can decrease platelet activation in humans.

Adult↗
PubMed2001

Individual metabolism should guide agriculture toward foods for improved health and nutrition.

Genomics and bioinformatics have the vast potential to identify genes that cause disease by investigating whole-genome databases. Comparison of an individual's geno-type with a genomic database will allow the prescription of drugs to be tailored to an individual's genotype. This same bioinformatic approach, applied to the study of human metabolites, has the potential to identify and validate targets to improve personalized nutritional health and thus serve to define the added value for the next generation of foods and crops. Advances in high-throughput analytic chemistry and computing technologies make the creation of a vast database of metabolites possible for several subsets of metabolites, including lipids and organic acids. In creating integrative databases of metabolites for bioinformatic investigation, the current concept of measuring single biomarkers must be expanded to 3 dimensions to 1) include a highly comprehensive set of metabolite measurements (a profile) by multiparallel analyses, 2) measure the metabolic profile of individuals over time rather than simply in the fasted state, and 3) integrate these metabolic profiles with genomic, expression, and proteomic databases. Application of the knowledge of individual metabolism will revolutionize the ability of nutrition to deliver health benefits through food in the same way that knowledge of genomics will revolutionize individual treatment of dis-ease with pharmaceuticals.

Biomarkers↗
PubMed2001

Fatty acid and triglyceride composition of milk fat from lactating Holstein cows in response to supplemental canola oil.

The objective was to determine the influence of dietary lipid on total and sn-2 fatty acid composition and triglyceride structure of milk fat in lactating Holstein cows. Five primiparous Holstein cows surgically fitted with ruminal and duodenal cannulas were used in a 4 x 5 incomplete Latin square. All cows received a basal diet. Treatments consisted of a basal diet with no supplemental canola oil (control), basal diet with canola oil added to the concentrate portion of the diet to provide 1.6% fat, basal diet with 330 g of canola oil infused directly into the rumen, and basal diet with 330 g of canola oil infused directly into the abomasum. Canola oil treatments decreased palmitic acid and increased oleic acid content of milk fat compared with the control. Stearate was higher when canola oil was rumen available compared with control and abomasal infusion. Abomasal infusion increased linoleic and linoleic acids in milk fat compared with the other treatments. The sn-2 fatty acid composition reflected total fatty acid composition. All canola oil treatments reduced palmitic acid and increased oleic acid content at the sn-2 position. Changes in sn-2 composition reflect specificity of the acyl transferases and substrate concentration. Triglyceride composition reported as carbon number was altered by canola oil. Triglycerides in carbon number C50, C52, and C54 were increased while C32, C34, and C36 were decreased.

Abomasum↗
PubMed2000

Lactoferrin in infant formulas: effect on oxidation.

Lactoferrin is an iron transport protein present in human milk at an average concentration of 1.4 mg/mL. Commercially modified infant formulas based on cow's milk contain much lower amounts of lactoferrin (0.1 mg/mL lactoferrin) and soy based formulas have none. In addition to its role in iron transport, lactoferrin has bacteriostatic and bactericidal activities. Infant formulas are supplemented with relatively large amounts of iron (up to 12 mg/L). The effect of various concentrations of added lactoferrin and supplemental iron on lipid oxidation was tested in two different infant formulas. The extent of oxidation in the formulas as a function of time was determined by formation of hydroperoxides, production of hexanal, and fluorescence. On the basis of all three of these determinations, lactoferrin acted as an antioxidant in the absence and presence of different concentrations of supplemented iron. Lactoferrin inhibited oxidation in a concentration-dependent manner even at concentrations beyond its capacity to bind iron at its two high affinity binding sites. Lactoferrin can be used, therefore, as a dual purpose additive in infant formulas and similar food products for its antioxidant and its antimicrobial properties.

Humans↗
PubMed2000

Activities of antioxidants are affected by colloidal properties of oil-in-water and water-in-oil emulsions and bulk oils.

The activity of alpha-tocopherol, Trolox, propyl gallate, gallic acid, methyl carnosoate, and carnosic acid was studied in two oil-in-water (o/w) emulsions, in two water-in-oil (w/o) emulsions, and in bulk oil with and without added emulsifiers. All antioxidants had either moderate or higher activity in bulk oil than in the emulsions. In most emulsions, the most polar antioxidants, propyl gallate and gallic acid, exhibited either prooxidant activity or no antioxidant activity. Methyl carnosoate was the most active antioxidant in w/o emulsions but was less active than Trolox in o/w emulsions. alpha-Tocopherol was less active in bulk oil than in emulsions, but its activity in bulk oil was markedly enhanced by the addition of o/w emulsifiers. Partitioning of antioxidants, hydrogen bonding, interphase transport, surface accessibility, and interaction of emulsifier with antioxidants are considered to be important parameters that determine antioxidant activity in lipid-containing systems.

Antioxidants↗
PubMed2000

(+)-Catechin in human plasma after ingestion of a single serving of reconstituted red wine.

BACKGROUND: Red wine consumption may decrease the risk of coronary heart disease through the actions of its constituent flavonoids. (+)-Catechin is an abundant flavonoid in red wine. OBJECTIVE: The objective was to determine changes in plasma (+)-catechin concentrations after ingestion of a single, moderate serving of dealcoholized red wine reconstituted with either water (DRW) or water and alcohol (ARW). DESIGN: Nine subjects (5 men, 4 women) ingested, in random order, 120 mL DRW on one day and 120 mL ARW on another day. Both the DRW and ARW contained 35 mg (121 micromol) free (+)-catechin. Blood samples were collected at 0, 0.5, 1, 2, 3, 4, and 8 h. Plasma was analyzed by gas chromatography-mass spectrometry for (+)-catechin after enzymatic release of sulfate and glucuronide conjugates. RESULTS: Calcium ions were needed to effectively hydrolyze (+)-catechin conjugates in plasma containing EDTA. Neither the ARW or DRW nor sex affected the area under the curve at 8 h, the maximum concentration (c(max)), or the time it took for plasma total (+)-catechin to reach maximum concentration (t(max)). Pooled mean (+/-SEM) values for the ARW and DRW were as follows: area under the curve, 306.1 +/- 29.5 nmol*h/L; c(max), 76.7 +/- 7.5 nmol/L; and t(max), 1.44 +/- 0.13 h. The half-life of (+)-catechin in plasma was significantly less (P = 0.038) after ingestion of the ARW (3.17 h) than after ingestion of the DRW (4.08 h). CONCLUSIONS: Increases in plasma total (+)-catechin concentrations were not significantly different after single moderate servings of either the ARW or DRW. Alcohol in the ARW hastened the elimination of (+)-catechin from the plasma compartment. (+)-Catechin elimination may represent excretion or conversion to methylated derivatives.

Adult↗
PubMed2000

Chronic marginal iron intakes during early development in mice result in persistent changes in dopamine metabolism and myelin composition.

Marginal iron (Fe) deficiency is prevalent in children worldwide, yet the behavioral and biochemical effects of chronic marginal Fe intakes during early development are not well characterized. Using a murine model, previous work in our laboratory demonstrated persistent behavioral disturbances as a consequence of marginal Fe intakes during early development. In the present study, Swiss-Webster mice fed a control Fe diet (75 microgram Fe/g diet, n = 13 litters) or marginal Fe diet (14 microgram Fe/g diet, n = 16 litters) during gestation and through postnatal day (PND) 75 were killed on PND 75 for assessment of tissue mineral concentrations, dopamine metabolism, myelin fatty acid composition, and c- and m-aconitase activities. In addition, these outcomes were assessed in a group of offspring (n = 13 litters) fed a marginal Fe diet during gestation and lactation and then fed a control diet from PND 21-75. Marginal Fe mice demonstrated significant differences in brain iron concentrations, dopamine metabolism and myelin fatty acid composition relative to control mice; however, no difference in c- or m-aconitase activity was demonstrated in the brain. The postnatal consumption of Fe-adequate diets among marginal Fe offspring did not fully reverse all of the observed biochemical disturbances. This study demonstrates that chronic marginal Fe intakes during early development can result in significant changes in brain biochemistry. The persistence of some of these biochemical changes after postnatal Fe supplementation suggests that they are an irreversible consequence of developmental Fe restriction.

Aconitate Hydratase↗