Biomedical subjects

M Thomas Clandinin

Publications and source records attributed to M Thomas Clandinin.

At least 19 recordsLinked to original sources

PubMed2006

The effect of treating infected skin grafts with Acticoat on immune cells.

A study was conducted to determine the effect of Acticoat placed on an infected skin graft on parameters of immunity. Two partial thickness wounds (2 cm x 4 cm) were created on the dorsal midline of Hartley guinea pigs (n=28). Wounds were covered with autologous skin graft and maintained either aseptically (Noninoculated, n=8), inoculated with Staphylococcus aureus (Surgery-Inoculated, n=8) with or without Acticoat bandage (Surgery-Inoculated-Acticoat, n=6). Five days later, splenocytes and blood were collected to estimate natural killer cell (NK) cytotoxicity, proliferative response to T and B cell mitogens and neutrophil oxidative burst. Animals that did not undergo surgery were included as a nonsurgery control group. [(3)H]-thymidine incorporation in response to a variety of T and B cell mitogens was significantly lower for all groups undergoing surgery compared to the nonsurgery control group (p<0.0001) and no additional effect was observed on this immune measure by applying the Acticoat bandage. The Surgery-Inoculated-Acticoat group exhibited greater NK cytotoxic activity (as assessed as the ability to lyse K562 tumor cells) compared to the Surgery-Inoculated group (p<0.006). The Surgery-Inoculated-Acticoat group had higher neutrophil oxidative burst at 5 min post stimulation, but was not different from controls after 15 min. In conclusion, the application of an Acticoat bandage to an inoculated surgery wound did not alter the low cell-mediated immune response that followed surgery, but appeared to increase parameters (NK cytotoxic activity and neutrophil function) of innate immunity.

Animals↗

PubMed2005

Dietary gangliosides increase the content and molecular percentage of ether phospholipids containing 20:4n-6 and 22:6n-3 in weanling rat intestine.

This study was conducted to determine whether dietary ganglioside (GG) increases the content of ether phospholipids (EPL) in intestinal mucosa. Weanling Sprague-Dawley rats were fed a semipurified diet consisting of 20% fat as a control diet. Two experimental diets were formulated by adding either 0.1% (w/w fat) GGs (GG diet) or 1.0% (w/w fat) sphingomyelin (SM diet) to the control diet. Fatty acid methyl esters from the alkenylacyl, alkylacyl and diacyl subclasses of phospholipids were measured to determine total and molecular percentage of EPL comprising the choline phosphoglyceride (CPG) and ethanolamine phosphoglyceride (EPG) fraction. Animals fed the GG diet significantly increased total EPL content both in CPG (by 36%) and in EPG (by 66%), and the molecular percentage of EPL in CPG (by 76%) and in EPG (by 59%) compared to animals fed the control diet. Dietary GG-induced increase in EPL resulted in a higher level of polyunsaturated fatty acids (PUFA) specifically in 20:4n-6 and 22:6n-3 compared to control animals, leading to a decrease in the ratio of saturated fatty acids (SFA) to PUFA both in CPG and in EPG. Feeding animals the SM diet showed a higher level of EPL than control animals with a concomitant increase in 22:6n-3 in EPL. The present data demonstrate that dietary GG increases the content and composition of EPL containing PUFA in the weanling rat intestine.

Animals↗

PubMed2005

Dietary ganglioside decreases cholesterol content, caveolin expression and inflammatory mediators in rat intestinal microdomains.

Membrane microdomains rich in cholesterol and sphingolipids, including gangliosides (GGs), are known to be important regions for cell signaling and binding sites for various pathogens. Cholesterol depletion inhibits the cellular entry of pathogens and also reduces inflammatory signals by disrupting microdomain structure. Our previous study showed that dietary gangliosides increased total ganglioside incorporation while decreasing cholesterol in the intestinal mucosa. We hypothesized that diet-induced reduction in cholesterol content in the intestinal mucosa disrupts microdomain structure resulting in reduced pro-inflammatory signals. Male weanling Sprague-Dawley rats were fed semipurified diets for 2 weeks. Experimental diets were formulated to include either ganglioside-enriched lipid (GG diet, 0.02% gangliosides [w/w of diet] ) or polyunsaturated fatty acid (PUFA diet, 1% arachidonic acid and 0.5% docosahexaenoic acid, w/w of total fat), in a control diet containing 20% fat. Levels of cholesterol, GG, caveolin, platelet activating factor (PAF), and diglyceride (DG) were measured in the microdomain isolated from the intestinal brush border. The GG diet increased total gangliosides by 50% with a relative increase in GD3 and a relative decrease in GM3. Cholesterol content was also reduced by 23% in the intestinal microdomain. These changes resulted in a significant decrease in the ratio of cholesterol to ganglioside. The GG diet and the PUFA diet were both associated with reduction in caveolin, PAF, and DG content in microdomains, whereas no change occurred in the ganglioside profile of animals fed the PUFA diet. Dietary gangliosides decrease the cholesterol/ganglioside ratio, caveolin, PAF and DG content in microdomains thus exerting a potential anti-inflammatory effect during gut development.

Animals↗

PubMed2005

Influence of dietary saturated fatty acids on the regulation of plasma cholesterol concentration.

The specific effects of individual fatty acids (FA) on plasma cholesterol levels, in the range habitually consumed by humans, on plasma cholesterol levels is not usually presented by the literature. Conclusions have been made regarding the cholesterolemic effect of individual FA, even though these FA cannot be tested individually. It appears that FA balance of the diet may be more important than individual FA intakes. Variation in plasma cholesterol response to diet is influenced by many factors, such as gene-nutrient interactions. The effect on human health of current processes used in the food industry that are certain to change dietary fat composition and TG structure is yet to be fully explored. Some of the relevant research regarding dietary fat and plasma cholesterol levels is reviewed.

Cholesterol↗

PubMed2005

Growth and development of preterm infants fed infant formulas containing docosahexaenoic acid and arachidonic acid.

OBJECTIVES: To evaluate safety and benefits of feeding preterm infants formulas containing docosahexaenoic acid (DHA) and arachidonic acid (ARA) until 92 weeks postmenstrual age (PMA), with follow-up to 118 weeks PMA. STUDY DESIGN: This double-blinded study of 361 preterm infants randomized across three formula groups: (1) control, no supplementation; (2) algal-DHA (DHA from algal oil, ARA from fungal oil); and (3) fish-DHA (DHA from fish oil, ARA from fungal oil). Term infants breast-fed > or =4 months (n = 105) were a reference group. Outcomes included growth, tolerance, adverse events, and Bayley development scores. RESULTS: Weight of the algal-DHA group was significantly greater than the control group from 66 to 118 weeks PMA and the fish-DHA group at 118 weeks PMA but did not differ from term infants at 118 weeks PMA. The algal-DHA group was significantly longer than the control group at 48, 79, and 92 weeks PMA and the fish-DHA group at 57, 79, and 92 weeks PMA but did not differ from term infants from 79 to 118 weeks PMA. Supplemented groups had higher Bayley mental and psychomotor development scores at 118 weeks PMA than did the control group. Supplementation did not increase morbidity or adverse events. CONCLUSIONS: Feeding formulas with DHA and ARA from algal and fungal oils resulted in enhanced growth. Both supplemented formulas provided better developmental outcomes than unsupplemented formulas.

Arachidonic Acid↗

PubMed2005

20:5n-3 but not 22:6n-3 is a preferred substrate for synthesis of n-3 very-long- chain fatty acids (C24-C36) in retina.

The objective of this study was to determine if 20:5n-3 or 22:6n-3 is the primary precursor of very-long-chain fatty acids (VLCFAs; C24-C36) synthesized in retina. Rats were fed semisynthetic, nutritionally complete diet containing 20% (w/w) fat with 3% (w/w) of 22:6n-3. After 6 weeks feeding, the vitreal fluid of each eye was injected with [3H]20:5n-3 or [3H]22:6n-3. Rats were then maintained under constant light (330 lux) or dark conditions for 48 hr. After 48 hr in vivo metabolism, the amount of label present in individual fatty acids was determined in major phospholipids in retina. For [3H]22:6n-3, 90% of total incorporation remained in 22:6n-3, whereas for [3H]20:5n-3 the label was actively incorporated into pentaenoic and hexaenoic VLCFAs up to 34 carbon chain length. 22:5n-3 derived from [3H]20:5n-3 was among the most highly labeled fatty acids. These observations suggest that 22:6n-3 is incorporated directly into retinal phospholipids without further metabolism, whereas 20:5n-3 and 22:5n-3 are metabolically active precursors for synthesis of VLCFAs.

Animals↗

PubMed2005

Diet-induced changes in membrane gangliosides in rat intestinal mucosa, plasma and brain.

OBJECTIVES: The objective of this study was to determine if dietary gangliosides induce changes in the ganglioside content of intestinal mucosa, plasma and brain and to identify where GM3 and GD3 are localized in the enterocyte membrane. METHODS: Male 18-day-old Sprague-Dawley rats were fed a semipurified diet containing 20% (w/w) fat. The control diet contained triglyceride, reflecting the fat formulation of an existing infant formula. Two experimental diets were formulated by adding sphingomyelin (1% w/w of total fat) or a ganglioside-enriched lipid (0.1% w/w of total fat) to the control diet fat. The ganglioside fraction of ganglioside-enriched lipid diet contained more than 80% GD3. After 2 weeks of feeding, the total and individual ganglioside and cholesterol content was measured in small intestinal mucosa, plasma and brain. RESULTS: The ganglioside-enriched lipid diet significantly increased total gangliosides in the intestinal mucosa, plasma and brain compared with the control diet. The ganglioside-enriched lipid diet significantly increased the level of GD3 (7.5% w/w) in the intestine compared with control (3.2% w/w) while decreasing the level of GM3, the major ganglioside in the intestine. The ratio of cholesterol to ganglioside in the intestinal mucosa, plasma and brain decreased significantly in rats fed the ganglioside-enriched lipid diet compared with controls. Confocal microscopy showed that GM3 is exclusively localized in the apical membrane of the enterocyte whereas GD3 is primarily localized in the basolateral membrane. CONCLUSIONS: : The authors conclude that dietary ganglioside is absorbed in the small intestine and transported to different membrane sites, altering ganglioside levels in the intestinal mucosa, plasma and brain and thus possibly having the potential to change developing enterocyte function (and possibly that of other cell lines).

Animals↗

PubMed2005

Dietary ganglioside and long-chain polyunsaturated fatty acids increase ganglioside GD3 content and alter the phospholipid profile in neonatal rat retina.

PURPOSE: During early development, the ganglioside composition of the retina changes significantly, in that GD3 becomes the primary ganglioside in the mammalian retina. Because gangliosides play an important role in neuronal cell differentiation and proliferation, this change in ganglioside profile may indicate retinal maturation. Dietary long-chain polyunsaturated fatty acids (LCPs) such as 20:4n-6 and 22:6n-3 improve visual acuity in infants. Dietary LCPs stimulate neonatal retinal development by altering membrane phospholipids, which in turn affect cell signaling pathways. It is unknown whether dietary ganglioside and LCPs affect the metabolism of phospholipids and gangliosides during retinal development. METHODS: Male Sprague-Dawley rats (18 days old) were fed semipurified diets consisting of 20% fat (control diet) for 2 weeks containing either 0.1% ganglioside enriched in GD3 (GG diet) or 1% 20:4n-6 and 0.5% 22:6n-3 (LCP diet) in the control diet. The profile of ganglioside and phospholipid was measured. RESULTS: The GG diet increased the ganglioside content by 39% in the retina, with a relative increase in GD3 (by 13%). Dietary LCPs significantly increased the relative levels of GD3 (by 19%, P < 0.01). Total phospholipid was decreased by the LCP-supplemented diet (by 28%). Phosphatidylcholine and phosphatidylserine increased with concomitant decreases in phosphatidylinositol and lyso-phosphatidylethanolamine when animals were fed either the LCP or the GG diet. CONCLUSIONS: Animals fed dietary ganglioside increased in total retinal ganglioside and GD3 content during retinal development, with a concomitant alteration of phospholipid metabolism. Feeding animals dietary LCPs also affected ganglioside metabolism in the developing retina, suggesting a new mechanism by which these dietary lipids may promote maturation of photoreceptor cells.

Animals↗

PubMed2004

Cofactor treatment improves ATP synthetic capacity in patients with oxidative phosphorylation disorders.

Marked progress has been made over the past 15 years in defining the specific biochemical defects and underlying molecular mechanisms of oxidative phosphorylation disorders, but limited information is currently available on the development and evaluation of effective treatment approaches. Metabolic therapies that have been reported to produce a positive effect include coenzyme Q(10) (ubiquinone), other antioxidants such as ascorbic acid and vitamin E, riboflavin, thiamine, niacin, vitamin K (phylloquinone and menadione), and carnitine. The goal of these therapies is to increase mitochondrial ATP production, and to slow or arrest the progression of clinical symptoms. In the present study, we demonstrate for the first time that there is a significant increase in ATP synthetic capacity in lymphocytes from patients undergoing cofactor treatment. We also examined in vitro cofactor supplementation in control lymphocytes in order to determine the effect of the individual components of the cofactor treatment on ATP synthesis. A dose-dependent increase in ATP synthesis with CoQ(10) incubation was demonstrated, which supports the proposal that CoQ(10) may have a beneficial effect in the treatment of oxidative phosphorylation (OXPHOS) disorders.

Adenosine Triphosphate↗

PubMed2003

Long chain polyunsaturated fatty acids are required for efficient neurotransmission in C. elegans.

The complex lipid constituents of the eukaryotic plasma membrane are precisely controlled in a cell-type-specific manner, suggesting an important, but as yet, unknown cellular function. Neuronal membranes are enriched in long-chain polyunsaturated fatty acids (LC-PUFAs) and alterations in LC-PUFA metabolism cause debilitating neuronal pathologies. However, the physiological role of LC-PUFAs in neurons is unknown. We have characterized the neuronal phenotype of C. elegans mutants depleted of LC-PUFAs. The C. elegans genome encodes a single Delta6-desaturase gene (fat-3), an essential enzyme for LC-PUFA biosynthesis. Animals lacking fat-3 function do not synthesize LC-PUFAs and show movement and egg-laying abnormalities associated with neuronal impairment. Expression of functional fat-3 in neurons, or application of exogenous LC-PUFAs to adult animals rescues these defects. Pharmacological, ultrastructural and electrophysiological analyses demonstrate that fat-3 mutant animals are depleted of synaptic vesicles and release abnormally low levels of neurotransmitter at cholinergic and serotonergic neuromuscular junctions. These data indicate that LC-PUFAs are essential for efficient neurotransmission in C. elegans and may account for the clinical conditions associated with mis-regulation of LC-PUFAs in humans.

Amino Acid Sequence↗

PubMed2003

The use of lymphocytes to screen for oxidative phosphorylation disorders.

Biochemical analysis of oxidative phosphorylation (OXPHOS) disorders is traditionally carried out on muscle biopsies, cultured fibroblasts, and transformed lymphocytes. Here we present a new screening technique using lymphocytes to identify OXPHOS dysfunction and initially avoid an invasive diagnostic procedure. Lymphocytes represent an easily obtainable source of tissue that presents advantages over the use of fibroblasts or lymphoblast cell lines. The time delay in culturing skin fibroblasts and the interactions between cell transformation and mitochondrial activity are avoided in this methodology. The method requires a small amount of blood (<5 mL); can be completed in a few hours, and allows for repeated measurements. Our assay has been adapted from published methods utilizing cultured fibroblasts and transformed lymphocytes, and our data suggest that measurement of ATP synthesis in lymphocytes is an effective screening tool for diagnosing OXPHOS disorders. This method may also provide an objective tool for monitoring response to treatment and evaluating progression of disease.

Adult↗

PubMed2003

Multinational study of major breast milk carotenoids of healthy mothers.

BACKGROUND: Carotenoids in serum vary between countries and within populations with evidence suggesting a qualitative relationship to diet. Breast milk carotenoids furnish a source of vitamin A and potentially provide immunoprotection and other health benefits for infants. There have been numerous studies of milk carotenoid concentrations in undernourished populations; however, carotenoid concentrations have not previously been compared in populations of well-nourished mothers. AIM OF STUDY: To compare concentrations of five major carotenoid groups: alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin, and lycopene in breast milk of healthy women from Australia, Canada, Chile, China, Japan, Mexico, the Philippines, the United Kingdom, and the United States, and to qualitatively compare patterns of dietary intake with milk carotenoid concentrations. METHODS: Breast milk collected from healthy lactating women was analyzed for concentrations of five carotenoids and retinol and quantitated relative to total milk lipid. All determinations were performed in a single research laboratory using standardized methodology. Mothers consumed their usual diets and provided a single 24-h dietary recall. RESULTS: Breast milk carotenoid concentrations varied greatly among countries, with the greatest differences in beta-cryptoxanthin (approximately 9-fold) and the least in alpha-carotene and lycopene (approximately 3-fold). Breast milk retinol concentrations varied approximately 2-fold across countries. The provitamin A carotenoids alpha-carotene, beta-carotene, and beta-cryptoxanthin as a group accounted for > 50 % of the carotenoids measured. Total breast milk carotenoids were highest in Japanese and lowest in Philippine mothers. Breast milk beta-carotene concentrations were highest in Chile and lowest in the Philippines. CONCLUSIONS: Patterns of breast milk carotenoids were unique to each country and qualitative patterns reflected the dietary carotenoid supply.

Adolescent↗

PubMed2003

Exchanging partially hydrogenated fat for palmitic acid in the diet increases LDL-cholesterol and endogenous cholesterol synthesis in normocholesterolemic women.

Partial hydrogenation of oil results in fats containing unusual isomeric fatty acids characterized by cis and trans configurations. Hydrogenated fats containing trans fatty acids increase plasma total cholesterol (TC) and LDL-cholesterol while depressing HDL-cholesterol levels. Identifying the content of trans fatty acids by food labeling is overshadowed by a reluctance of health authorities to label saturates and trans fatty acids separately. Thus, it is pertinent to compare the effects of trans to saturated fatty acids using stable isotope methodology to establish if the mechanism of increase in TC and LDL-cholesterol is due to the increase in the rate of endogenous synthesis of cholesterol. Ten healthy normocholesterolemic female subjects consumed each of two diets containing approximately 30% of energy as fat for a fourweek period. One diet was high in palmitic acid (10.6% of energy) from palm olein and the other diet exchanged 5.6% of energy as partially hydrogenated fat for palmitic acid. This fat blend resulted in monounsaturated fatty acids decreasing by 4.9 % and polyunsaturated fats increasing by 2.7%. The hydrogenated fat diet treatment provided 3.1% of energy as elaidic acid. For each dietary treatment, the fractional synthesis rates for cholesterol were measured using deuterium-labeling procedures and blood samples were obtained for blood lipid and lipoprotein measurements. Subjects exhibited a higher total cholesterol and LDL-cholesterol level when consuming the diet containing trans fatty acids while also depressing the HDL-cholesterol level. Consuming the partially hydrogenated fat diet treatment increased the fractional synthesis rate of free cholesterol. Consumption of hydrogenated fats containing trans fatty acids in comparison to a mixtur e of palmitic and oleic acids increase plasma cholesterol levels apparently by increasing endogenous synthesis of cholesterol.

Adult↗

PubMed2003

Nutritional cofactor treatment in mitochondrial disorders.

Mitochondrial disorders are degenerative diseases characterized by a decrease in the ability of mitochondria to supply cellular energy requirements. Substantial progress has been made in defining the specific biochemical defects and underlying molecular mechanisms, but limited information is available about the development and evaluation of effective treatment approaches. The goal of nutritional cofactor therapy is to increase mitochondrial adenosine 5'-triphosphate production and slow or arrest the progression of clinical symptoms. Accumulation of toxic metabolites and reduction of electron transfer activity have prompted the use of antioxidants, electron transfer mediators (which bypass the defective site), and enzyme cofactors. Metabolic therapies that have been reported to produce a positive effect include Coenzyme Q(10) (ubiquinone); other antioxidants such as ascorbic acid, vitamin E, and lipoic acid; riboflavin; thiamin; niacin; vitamin K (phylloquinone and menadione); creatine; and carnitine. A literature review of the use of these supplements in mitochondrial disorders is presented.

Adenosine Triphosphate↗

PubMed2003

Dietary lipids alter the effect of steroids on the transport of glucose after intestinal resection: Part I. Phenotypic changes and expression of transporters.

BACKGROUND/PURPOSE: Glucocorticosteroids alter the function of the intestine. This study was undertaken to assess the effect on D-glucose uptake of budesonide (Bud), prednisone (Pred), or dexamethasone (Dex) in animals with a 50% intestinal resection and fed chow or a diet enriched with saturated (SFA) or polyunsaturated fatty acids (PUFA). METHODS: In vitro ring uptake technique, Western blots, and Northern blots were performed. RESULTS: Bud increased the jejunal D-glucose uptake, and this effect was prevented by feeding PUFA. SGLT1 and Na+/K+ ATPase protein and mRNA abundance did not correlate with the change in the rate of uptake of glucose. CONCLUSIONS: (1) Bud increased the jejunal glucose uptake, (2) the activity of the sugar transporter does not correlate with the abundance of protein or their respective mRNAs, (3) th Bud effect on glucose uptake is prevented by feeding PUFA. Thus, the desired intestinal adaptive response after intestinal resection may be enhanced further by the administration of the locally acting steroid budesonide and by feeding a saturated compared with a polyunsaturated fatty acid diet.

Animals↗

PubMed2003

Dietary lipids alter the effect of steroids on transport of glucose after intestinal resection: Part II. Signalling of the response.

BACKGROUND/PURPOSE: Glucocorticosteroids alter the function of the intestine. Budesonide (Bud) increases the jejunal D-glucose uptake, and this effect is prevented through a polyunsaturated fatty acid (PUFA) diet. This study was undertaken to assess the possible signalling effect of budesonide, prednisone (Pred), or dexamethasone (Dex) in animals with a 50% intestinal resection and fed chow or a diet enriched with saturated (SFA) or polyunsaturated fatty acids. METHODS: Northern blots were performed. RESULTS: Steroids reduced the jejunal but not the ileal expression of proglucagon. Ornithine decarboxylase (ODC) expression was reduced in the jejunum. CONCLUSIONS: c-jun, ODC, and proglucagon may be involved in the adaptive response that occurs with steroids and variations in dietary lipids after intestinal resection.

Anastomosis, Surgical↗

PubMed2002

The role of dietary long-chain n-3 fatty acids in anti-cancer immune defense and R3230AC mammary tumor growth in rats: influence of diet fat composition.

We determined if long-chain n-3 fatty acids fed as part of a: (1) high polyunsaturated fat diet (currently recommended by several health agencies) or (2) low polyunsaturated fat diet (representative of that consumed by a large segment of the North American population) improved antitumor immune defense and inhibited tumor growth. Rats were fed one of four semi-purified diets (20% w/w fat) for 21 days pre- and 17 days post- R3230AC mammary tumor implantation. The polyunsaturated to saturated fatty acid (P/S) ratio was either 1 (high P/S diet) or 0.35 (low P/S diet). At each P/S ratio, diets provided long-chain n-3 fatty acids at 0 or 5% w/w of total fat. Long-chain n-3 fatty acids fed in a high P/S diet did not affect tumor growth or host immune responses. In contrast, feeding long-chain n-3 fatty acids in a low P/S diet increased natural killer cell cytotoxicity, splenocyte nitric oxide and interleukin-2 production, and the proportion of activated (CD25+) CD8+ and CD28+ cells, but did not significantly inhibit tumor growth. For both P/S diets, tumor cells from rats fed long-chain n-3 fatty acids had a higher n-3 content and n-3/n-6 ratio in phosphatidylcholine, phosphatidylethanolamine, and phosphatidylinositol. Furthermore, the magnitude of increase in n-3 fatty acid incorporation into tumor phospholipids was greater when fed in a low P/S diet. We demonstrated that the dietary P/S ratio significantly influences the effect of long-chain n-3 fatty acids on host immune responses and n-3 fatty acid incorporation into tumor cells. These findings warrant further consideration when designing dietary recommendations.

Animals↗

PubMed2002

Cholesterolaemic effect of palmitic acid in relation to other dietary fatty acids.

The effect of dietary intake of high palmitic acid levels in combination with other fatty acids in normal subjects was assessed. Palmitic acid (10% of energy) was fed in conjunction with decreasing levels of linoleic acid to determine if a threshold level of linoleic acid prevented palmitic acid from being hypercholesterolaemic. Healthy subjects received each of the diet treatments for 21 days, followed by washout periods of 7 days. In a second experiment, the effect of exchanging palmitic acid for trans fatty acids on plasma lipoprotein cholesterol levels and on rates for endogenous synthesis of cholesterol in normal subjects was investigated. Diet treatment lasted for 30 days. On day 30 of each diet treatment, a priming dose of deuterium was consumed, followed by a subsequent blood sample at 24 h. Blood cholesterol fractions were isolated and analysed by isotope ratio mass spectrometry to measure cholesterol fractional synthetic rates. In the first experiment, total plasma cholesterol levels increased as the percentage of linoleic acid decreased. The data indicated that high levels of palmitic acid were not hypercholesterolaemic if intake of linoleic acid was greater than 4.5% of energy. When the diet contained trans fatty acids plasma total and low-density lipoprotein-cholesterol increased and cholesterol synthesis increased with a decrease in high-density lipoprotein-cholesterol.

Adult↗