LCT Emulsions Research Articles

Impact of oil type and WPI/Tween 80 ratio at the oil-water interface: Adsorption, interfacial rheology and emulsion features.

The relationship between the composition and structure of food emulsions was evaluated from the effect of a mixture of emulsifiers Whey protein (WPI) - Tween 80 (T80) and the oil phase features, such as chain length and unsaturation degree (sunflower oil, a long chain triacylglycerol - LCT or NEOBEE® 1053, a medium chain triacylglycerol - MCT). Emulsions with LCT showed higher droplet size than MCT as a consequence of its higher viscosity. All emulsions exhibited shear thinning behavior, but the viscosity was influenced by their interface composition. An occurrence of the destabilization mechanism by creaming was observed in turbidimetric measurements, but no visual phase separation could be observed, indicating a good kinetic stability after a 7-day storage. The initial interfacial tension of the water-LCT or water-MCT oil was about 25 mN/m, but the WPI addition (1% w/w) reduced the initial interfacial tension to approximately 20 mN/m. The increase of T80 concentration led to a decrease of the interfacial tension, reaching a value around 10 mN/m in systems with pure T80. The curves of interfacial tension of systems with LCT or MCT showed differences in the decay rate of tension over time. These differences were attributed to characteristics of the oil phase (hydrophobicity, unsaturation degree, presence of impurities) and the different proportions of each emulsifier within the mixture of emulsifiers. Finally, a higher viscoelastic interface was observed in LCT emulsions, which were mainly stabilized by WPI molecules. Such molecules presented a higher resistance to the displacement due to the competitive adsorption phenomenon, since the LCT is a more hydrophobic oil. On the other hand, the interface with MCT and a higher T80 concentration was less viscoelastic due to an easier displacement of WPI from the interface and the replacement by T80. The results indicate that T80 can be used in combination with WPI to produce emulsions with good stability and lower concentration of synthetic compounds. Lastly, the interfacial layer composition is not only dependent on the WPI-T80 ratio in the bulk phase, but also on the oily phase features. These results provide a potential strategy for designing emulsified foods based on the choice of ingredients and knowledge of the interaction between them.

Influence of carrier oil type, particle size on in vitro lipid digestion and eugenol release in emulsion and nanoemulsions

Consumption of essential oils (EOs) and their components, such as eugenol (EU) may reduce chronic disorders, but their use in food is currently limited because of poor solubility and low bioavailability. The aim of this work was to study the influence of carrier oil type, particle size on in vitro lipid digestion and EU release using canola (LCT) and MCT oil-in-water emulsions with different droplet diameters (Coarse > 3000 nm, NE1 > 300 nm and NE2 > 150 nm). There was a progressive increase in the mean particle size of coarse emulsions of both LCT & MCT oils as they passed through simulated gastrointestinal tract consisting of mouth, stomach and intestine phases, which was due to droplet coalescence, flocculation and digestion. However, NE1 and NE2 nanoemulsions showed appreciable increase in particle size after exposure to the simulated intestinal fluid. The rate and extent of in vitro lipid digestion increased with decreasing mean droplet diameter (NE2 ≈ NE1 » Coarse) in both MCT & LCT emulsions. However, MCT emulsions showed faster rate of in vitro lipid digestion which was attributed to more exposure of droplets with the lipase. There was also an appreciable increase in release percentage of eugenol with decreasing droplet diameter (NE2 > NE1 > Coarse) and it was higher in LCT (84%) emulsions which was attributed to large hydrophobic cores that better solubilize EU.

Quantitative analysis of the effect of triglyceride alkyl-chain length on the partitioning of highly lipophilic compounds to the mesenteric lymph in intestinal cells

The purpose of this study was to quantitatively clarify the effect of alky-chain length of a triglyceride in an emulsion on the partitioning of highly lipophilic compounds into the lymph fluid after their oral administration. Highly lipophilic anthraquinone derivatives were orally administered in emulsions to rats. Emulsions composed of long-, medium-, and short-chain triglycerides (LCT, MCT, and SCT emulsions, respectively) were used. The concentrations of the compounds in plasma and lymph fluid were periodically determined and their partitioning to the lymph was calculated using a mathematical model. Intestinal absorption of all compounds was enhanced and the plasma concentrations of the compounds were found to be in the following order: LCT emulsion > MCT emulsion > SCT emulsion. The amounts of each compound recovered in the lymph were not in agreement with their lipophilicity. Quantitative analysis revealed that the partitioning of the compounds to the lymph may be determined by the solubility of the compound in the triglyceride in the form of an emulsion and the amount of triglyceride transferred to the lymph fluid. These results suggest a possibility that the amount of a compound absorbed via the lymph route after oral administration can be quantitatively controlled by the formulations.

Hepatocellular integrity in patients requiring parenteral nutrition: comparison of structured MCT/LCT vs. a standard MCT/LCT emulsion and a LCT emulsion: Retraction

Hepatocellular integrity in patients requiring parenteral nutrition: comparison of structured MCT/LCT vs. a standard MCT/LCT emulsion and a LCT emulsion: Retraction

Immune function and leukocyte sequestration under the influence of parenteral lipid emulsions in healthy humans: a placebo-controlled crossover study

Background: It remains unclear whether immune modulation by lipids contributes to the high risk of infectious complications that is associated with the use of parenteral nutrition. Although mixed long- and medium-chain triacylglycerol (LCT-MCT)–containing emulsions, but not pure LCT emulsions, activate neutrophils and impair crucial leukocyte functions in vitro, in vivo studies have failed to corroborate these findings.Objectives: The present investigation was conducted to evaluate the effects of LCT and LCT-MCT on immune function in healthy humans and to assess whether the lack of in vivo effects results from sampling errors due to extravascular sequestration of activated neutrophils.Design: Saline, LCT-MCT, and LCT emulsions were administered intravenously for 4.5 h to 12 healthy volunteers in a randomized crossover design. Plasma triacylglycerol concentrations were clamped at a clinically relevant concentration of 3–5 mmol/L. Leukocyte population counts and neutrophil activation were assessed before and after infusion. Leukocyte sequestration was evaluated by monitoring the distribution of Technetium-99m–labeled autologous leukocytes during infusions.Results: Whereas LCT exerted no greater effects than did saline, LCT-MCT significantly decreased lymphocyte counts. However, no evidence for neutrophil activation was found with either lipid. Moreover, the clearance of radiolabeled leukocytes from the liver, spleen, and lungs was not altered by any lipid, which suggested that lipid emulsions do not induce leukocyte sequestration.Conclusions: Short-term infusion of LCT-MCT (but not LCT) to healthy humans modulates leukocyte population counts but, in clear contrast with the in vitro situation, does not induce neutrophil activation. These disparate findings cannot be explained by MCT-induced leukocyte sequestration.

Efficacy of Medium-chain Triglycerides Compared with Long-chain Triglycerides in Total Parenteral Nutrition in Patients with Digestive Tract Cancer Undergoing Surgery

The objectives of this prospective, randomized study were to evaluate the efficacy and tolerability of the short-term use of medium-chain triglyceride/long-chain triglyceride (MCT/LCT) fat emulsions, and to compare the hematologic and biochemical effects of MCT/LCT fat emulsions with LCT fat emulsions in gastrointestinal (GI) tract cancer patients following surgery. Thirty patients with GI tract cancer requiring total parenteral nutrition (TPN) were equally randomized to receive MCT/LCT or LCT emulsions for 7 days. After 7 days, no sign of complications directly related to administration of fat emulsions was observed and there were no marked differences in anthropometry, length of hospital stay, and surgical complication rates between the two groups. However, MCT/LCT significantly improved plasma prealbumin concentration (p = 0.005). Changes in complements C3 and C4, total lymphocyte count, and immunoglobulins after TPN were not significantly different between the groups. Serum triglyceride and cholesterol levels remained constant. The serum insulin level in the MCT/LCT group was higher than in the LCT group (p = 0.048). Our data revealed that MCT/LCT fat emulsions significantly enhanced nutritional status in patients with GI tract cancer, indicated by higher prealbumin levels, which might be partially due to the higher circulating insulin levels in the MCT/LCT group.

Changes in Concentrations of Free Propofol by Modification of the Solution

Because free propofol is thought to be responsible for pain on injection, we investigated the changes in concentrations of free propofol by modifying two kinds of propofol products in a medium- and long-chain triglyceride (MCT/LCT) emulsion and in an LCT emulsion. The techniques used in this study were 1) mixing 2% lidocaine (10:1), 2) mixing 5% dextrose in acetated Ringer's solution to reduce pH (10:1), and 3) changing the temperature to 4 degrees , 20 degrees , and 36 degrees C. The propofol preparations were dialyzed for 24 h, and the receptor medium was analyzed using high-performance liquid chromatography. The concentration of free propofol in propofol MCT/LCT was significantly smaller by 30% than that in propofol LCT. Neither mixing lidocaine nor cooling reduced the concentrations of free propofol in both products, but the concentrations were reduced by a decrease in pH and by an increase in temperature. Because mixing lidocaine can induce instability in an emulsion of propofol and warming can rapidly induce microbial growth, injection of lidocaine before propofol administration is recommended to reduce the pain on injection. The concentrations of free propofol in propofol MCT/LCT were significantly smaller (by approximately 30%-45%) than those in propofol LCT during any situation in this study. Neither mixing lidocaine nor cooling reduced the concentrations of free propofol in both products but the concentrations were reduced by a decrease in pH and by an increase in temperature. Propofol medium- and long-chain triglycerides had significantly smaller concentrations by approximately 30%-45% than those in propofol long-chain triglycerides during any situation in this study.

Comparative Study between Propofol in a Long-chain Triglyceride and Propofol in a Medium/Long-chain Triglyceride during Sedation with Target-controlled Infusion

This study was performed to compare the pharmacological characteristics of propofol in an emulsion of both medium- and long-chain triglycerides (MCT/LCT) with those of propofol in an LCT emulsion, by measuring the sedative level and the plasma concentration of propofol during sedation using a target-controlled infusion (TCI) technique. Forty ASA 1 or 2 adult patients who required spinal anaesthesia for surgery were enrolled in this study. The patients were divided into two groups: a propofol LCT group (n = 20) and a propofol MCT/LCT group (n = 20). Propofol was injected intravenously at target blood concentrations of 2.0, 3.0 and 4.0 microg x ml(-1). The bispectral (BIS) index was recorded, and arterial blood was drawn to measure the actual plasma concentrations of propofol at each predicted concentration. Propofol was assayed by high-performance liquid chromatography. Propofol MCT/LCT was associated with significantly less pain than propofol LCT (P < 0.05). There were no significant differences between the two groups in BIS index or in plasma concentration of propofol at each predicted concentration. Computer-generated TCI of propofol MCT/LCT during sedation is comparable with that of propofol LCT with respect to pharmacokinetics and pharmacodynamics. The formulation of MCT/LCT has a beneficial effect with respect to less pain on injection.

Hepatic reticuloendothelial function during parenteral nutrition including an MCT/LCT or LCT emulsion after liver transplantation - a double-blind study

Hepatic reticuloendothelial function during parenteral nutrition including an MCT/LCT or LCT emulsion after liver transplantation - a double-blind study

Persistent messles virus (MV) infection of lleal lymphoid tissue in children with lise-colonic lymphoid nodular hyperplasia, entero-colitis and developmental disorder

<h2>Abstract</h2> <b>Background & Aims:</b> It is unclear whether fat digestion is required for the induction of gastrointestinal sensations and whether different fats have different effects. We investigated the effect of fat digestion and of medium-chain triglycerides (MCTs; C < 12) and long-chain triglycerides (LCTs; C > 16) on gastrointestinal sensations. <b>Methods:</b> In a double-blind study, 15 healthy subjects were studied on 5 occasions during which LCT or MCT emulsions (2 kcal/min), with or without 120 mg tetrahydrolipstatin (THL, lipase inhibitor), or sucrose polyester (SPE, nondigestible fat) were infused intraduodenally in randomized order. After 30 minutes, the proximal stomach was distended in 1 mm Hg steps/min. Intensity of gastrointestinal sensations (on a 0–10 visual analog scale), plasma cholecystokinin (CCK) levels, and gastric volumes were assessed throughout. <b>Results:</b> LCT and MCT increased gastric volume at baseline pressure compared with SPE, and LCT more than MCT. THL entirely abolished this effect (volumes [mL]: LCT, 213 ± 19; LCT-THL, 39 ± 3; MCT, 155 ± 12; MCT-THL, 43 ± 5; SPE, 44 ± 5). Only LCT increased plasma CCK levels (pmol/L per 30 minutes: LCT, 21 ± 2; LCT-THL, 9 ± 1; MCT, 9 ± 1; MCT-THL, 11 ± 1; SPE, 9 ± 1). During distentions, intragastric volumes were greater during infusion of LCT and MCT than during the respective THL conditions or SPE, but plasma CCK levels did not change. The intensity of sensations increased (hunger decreased) more with LCT than with MCT. During infusion of THL or SPE, the effects were smaller than during LCT or MCT. <b>Conclusions:</b> Fat digestion is required for the modulation of gastrointestinal sensations during gastric distention. The effects of fat depend on the fatty acid chain length and are not entirely explained by release of CCK. GASTROENTEROLOGY 2001;120:1100-1107

Fat digestion modulates gastrointestinal sensations induced by gastric distention and duodenal lipid in humans

It is unclear whether fat digestion is required for the induction of gastrointestinal sensations and whether different fats have different effects. We investigated the effect of fat digestion and of medium-chain triglycerides (MCTs; C < 12) and long-chain triglycerides (LCTs; C > 16) on gastrointestinal sensations. In a double-blind study, 15 healthy subjects were studied on 5 occasions during which LCT or MCT emulsions (2 kcal/min), with or without 120 mg tetrahydrolipstatin (THL, lipase inhibitor), or sucrose polyester (SPE, nondigestible fat) were infused intraduodenally in randomized order. After 30 minutes, the proximal stomach was distended in 1 mm Hg steps/min. Intensity of gastrointestinal sensations (on a 0-10 visual analog scale), plasma cholecystokinin (CCK) levels, and gastric volumes were assessed throughout. LCT and MCT increased gastric volume at baseline pressure compared with SPE, and LCT more than MCT. THL entirely abolished this effect (volumes [mL]: LCT, 213 +/- 19; LCT-THL, 39 +/- 3; MCT, 155 +/- 12; MCT-THL, 43 +/- 5; SPE, 44 +/- 5). Only LCT increased plasma CCK levels (pmol/L per 30 minutes: LCT, 21 +/- 2; LCT-THL, 9 +/- 1; MCT, 9 +/- 1; MCT-THL, 11 +/- 1; SPE, 9 +/- 1). During distentions, intragastric volumes were greater during infusion of LCT and MCT than during the respective THL conditions or SPE, but plasma CCK levels did not change. The intensity of sensations increased (hunger decreased) more with LCT than with MCT. During infusion of THL or SPE, the effects were smaller than during LCT or MCT. Fat digestion is required for the modulation of gastrointestinal sensations during gastric distention. The effects of fat depend on the fatty acid chain length and are not entirely explained by release of CCK.

Medium-chain, triglyceride-containing lipid emulsions increase human neutrophil beta2 integrin expression, adhesion, and degranulation.

To test the hypothesis that lipid emulsions with different triglyceride structures have distinct immunomodulatory properties, we analyzed human neutrophil adhesion and degranulation after lipid incubation. Neutrophils, isolated from the blood of 10 healthy volunteers, were incubated in medium or physiologic (2.5 mmol/L) emulsions containing long-chain (LCT), medium-chain (MCT), mixed LCT/MCT, or structured (SL) triglycerides. Expression of adhesion molecules and degranulation markers was evaluated by flow cytometry. Also, functional adhesion was investigated by means of a flow cytometric assay using fluorescent beads coated with the integrin ligand intercellular adhesion molecule (ICAM)-1. Although LCT and SL had no effect, LCT/MCT significantly increased expression of the beta2 integrins lymphocyte-function-associated antigen 1 (+18%), macrophage antigen 1 (+387%), p150,95 (+82%), and (alphaDbeta2 (+230%). Degranulation marker expression for azurophilic (CD63, +210%) and specific granules (CD66b, +370%) also significantly increased, whereas L-selectin (CD62L, -70%) decreased. The effects of LCT/MCT were mimicked by the MCT emulsion. ICAM-1 adhesion (% beads bound) was increased by LCT/MCT (34% +/- 4%), whereas LCT (19% +/-3%) and SL (20% +/- 2%) had no effect compared with medium (17% +/- 3%). LCT/MCT and MCT, contrary to LCT and SL emulsions, increased neutrophil beta2 integrin expression, adhesion, and degranulation. Apart from other emulsion constituents, triglyceride chain length might therefore be a key feature in the interaction of lipid emulsions and the phagocyte immune system.

Antioxidant status of surgical patients receiving TPN with an Ω-3-fatty acid-containing lipid emulsion supplemented with α-tocopherol

Background: LCT lipid emulsions and even more fish oil-containing lipid emulsions are under debate regarding their tocopherol and PUFA content as well as their effect on the antioxidative status especially in patients with oxidative stress.Methods: Thirty-three patients undergoing major abdominal surgery were randomly assigned to receive either an α-tocopherol-supplemented (562 μmol/l) MCT/LCT/omega-3-acid triglycerides (MLF, 5/4/1 w/w/w, 20%) emulsion or a soybean oil-based LCT emulsion (20%). The TPN regimen continously provided 1.4 g fat kg bw−1d−1over 5 days.Results: Plasma antioxidant concentrations were strongly reduced by surgical treatment. Following 5 days of TPN with the MLF emulsion, mean plasma α-tocopherol increased by 20.0 μmol/l (1.98 μmol/mmol lipid), while nearly no change was observed in the LCT emulsion group. In both groups, plasma concentrations of all non-supplemented antioxidants (vitamin C, carotenoids, selenium) as well as serum total antioxidant capacity further decreased during TPN. The concentrations of plasma cholesterol oxidation products as a measure of in vivo lipid peroxidation revealed no changes over the TPN period in either group.Conclusion: In contrast to the LCT emulsion, administration of the a-tocopherol supplemented MLF lipid emulsion normalized a-tocopherol plasma concentrations. Despite its high long-chain PUFA content, no hint for increased lipid peroxidation was found.

Fish oil emulsions: what benefits can they bring?

Recent advances indicate great potential for new fish oilcontaining lipid emulsions: the possible mechanisms involve suppression of excessive endothelial activity and thereby decreased production of pro-inflammatory mediators. This means that supplemental fish oil (n-3 fatty acids [FA]) may reduce inflammatory and thrombotic responses while protecting tissue microperfusion and immunity. Consequently, supplementation with fish oil might be used to improve standard clinical therapy, especially in chronic hyper-inflammatory diseases and as an adjunct therapeutic measure after trauma, injury, and during early sepsis. Encouraging effects with supplemental fish oil are observed in patients with chronic catabolism associated with cancer cachexia. Suppression of T-cell mediated immune function is an adverse effect with fish oil supplementation. This undesirable effect is partly due to increased lipid peroxidation and decreased antioxidant capacity and can be prevented by appropriate vitamin E supplementation. Parenteral administration of fish oil based emulsions might be advantageous compared to the enteral route because intestinal loss due to lipid remodelling is bypassed. A new type of emulsion made of a physical mixture of soybean-LCT, MCT, olive oil, and fish oil supplemented with vitamin E has been developed. This novel emulsion with reduced content of n-6 FA, high share of MUFAs and increased amount of n-3 FA is composed according to a current NIH recommendation. A randomized double blind clinical trial with the new emulsion revealed rapid incorporatiom of EPA and DHA in cell membranes resulting in a considerably decreased AA/EPA ratio. A profound increase of LTB5 and simultaneous decrease of LTB4 resulted in a marked decrease of the LTB 4/LTB5 ratio. TxB3 increased and TxB2 decreased. These changes are in accordance with the expected biochemical action of fish oil supplementation. We observed a 7 days shorter hospitalization with the new emulsion compared with the standard control LCT emulsion. The results suggest a beneficial immunomodulation probably due to parenteral provision of n-3 FA and olive oil and also because of the considerable reduction of n-6 FA and indicate that it is possible to establish fish oil supplementation protocols that provide maximum beneficial effects while adverse effects are minimized. Future studies need to be focussed on further elucidation of the intra and inter cellular signalling events mediated by n-3 FA. Understanding the molecular mechanism(s) modified by fish oils will ultimately lead to improved dietary strategies to aid the prevention of auto-immune disease, cardiovascular disease, certain type of cancer and to support therapeutical measures of trauma, sepsis and other acute illnesses. There is strong evidence that the future major feature in clinical nutrition in critically ill and chronic illness will be the creation of the optimum lipid emulsion for use in the most beneficial nutrient admixture. The fish oil story ‐ how it started

Physicochemical stability of two types of intravenous lipid emulsion as total nutrient admixtures.

Recent data have demonstrated that total nutrient admixtures (TNAs) are unstable when the percentage of fat (PFAT) globules >5 microm in diameter constitute >0.4% of the total fat present and therefore can be considered pharmaceutically unfit for human administration. We studied five nutritionally balanced TNAs using two different products of different oil composition designed to feed adult patients weighing 40 to 80 kg in 10 kg increments, which were given in final volumes equal to 25 mL/kg. Final concentrations of amino acids, dextrose, and lipids were held constant for each weight level. To provide cationic stress within clinical limits, calcium and magnesium were given in amounts equal to three times the usual daily dose, at 15 mmol each. Five TNAs were made in duplicate and for each product (n = 20) and studied over 5 days. Lipid droplet counts were determined by laser light extinction and conducted at five intervals; immediately after preparation at time 1 (T1), after 4 days at 4 degrees C +/- 2 degrees C (T2), and then at 6 (T3), 24 (T4), and 30 (T5) hours during storage at 25 degrees C +/- 1 degree C. At T3, a simulated patient infusion, set at a rate to deliver the entire volume over the next 24 hours, was begun. Samples taken at T3, T4, and T5, equal to 0, 18, and 24 hours, respectively, of the simulated patient infusion, were collected from the terminal infusion port of the i.v. administration set. Mean particle size (MPS) was determined by dynamic light scatter at T1, T3, and T5. Dependent variable analyses included the PFAT globules > 1.75 and 5 microm and MPS. A repeated-measure two-way ANOVA assessing treatment and time was performed. The MCT/LCT-based TNAs had significantly fewer enlarged fat globules >1.75 microm (p < .0001) and >5 microm (p = .046), and smaller MPS (p < .0001) than TNAs made with the pure LCT emulsion. Of the 20 TNAs studied, 4 demonstrated visible evidence of instability (ie, heavy creaming or free oil), each occurring on day 5 only with the 70- and 80-kg LCT-based TNAs, and no evidence of instability with admixtures prepared from MCT/LCT lipid emulsions (chi2 analysis: p < .05). Because the final macronutrient concentrations were held constant, the instability seen with the LCT-based TNAs of higher volumes may result from dilution of the electrolyte concentrations that unfavorably alters the electrical double layer and irreversibly commits the emulsion to an unstable state. The greater physicochemical stability achieved with the MCT/LCT-based TNAs, in turn, likely results from the smaller lipid droplet sizes, which may be an inherent property of MCTs.

Blood clearance and tissue uptake of intravenous lipid emulsions containing long-chain and medium-chain triglycerides and fish oil in a mouse model.

Increasing interest in using different triglycerides (TGs) for specific clinical applications raised the question as to how the emulsion TG composition would affect blood clearance and emulsion delivery to hepatic and extrahepatic tissues. Emulsions used were long-chain soy oil TG (long-chain triglyceride [LCT]), LCT/ medium-chain triglyceride (MCT; 1:1, wt/wt), LCT/MCT/C/omega-3 (5:4:1, wt/wt) and pure fish oil (omega-3 TG) labeled with non-degradable 3H-cholesteryl oleoyl ether (3H-CE) as a particle marker. Mice (C57BL/6J) were injected with four different commercial emulsions at a nonsaturating dose of 0.4 mg TG/20 to 25 g per mouse to obtain 1st order kinetics. Blood was sampled at 0.5, 2, 5, 10, 15, and 25 minutes, and the fractional catabolic rate was determined by fitting a straight line to the logarithm of the blood 3H-CE radioactivity. Retention of 3H-CE for each tissue at 25 minutes reflected organ uptake of the emulsion. Blood clearance of pure omega-3 TG (10.40% +/- 0.54% pools/h; mean +/- SE) was significantly slower than that of LCT, LCT/MCT, and LCT/MCT/omega-3 emulsion (18.9 +/- 0.6 pools/h, 17.0 +/- 0.96 pools/h, 16.5 +/- 1.08 pools/h, respectively) (p < .01). Based on 3H-CE uptake, LCT, LCT/MCT, and omega-3 TG emulsions showed similar delivery to liver (39% +/- 3.9%, 46% +/- 3.6%, 34% +/- 3.2%). Liver uptake of LCT/MCT/omega-3, (23% +/- 2.2%) was less than LCT/MCT (46% +/-3.6%, p < .0001) and LCT (39% +/- 3.9%, p = .002). Results indicate slow blood clearance of pure omega-3 TG emulsion from the blood compared with emulsion in which omega-3 TG was mixed with LCT and MCT. Earlier data showed that omega-3 TG are poorly hydrolyzed in extracellular media and therefore are delivered to tissues as part of the core of emulsion remnants. Thus, our data suggest that the incorporation of omega-3 TG with LCT/MCT will result in greater delivery of omega-3 fatty acids to extrahepatic tissue, which could be important in modulating immune and other responses.

Hypotriglyceridaemic activity of Ficus carica leaves in experimental hypertriglyceridaemic rats.

A model of hypertriglyceridaemia in rats is described, which was used to investigate the hypolipidaemic effect of an intraperitoneal (i./p.) administration of a Ficus carica leaf decoction. Hypertriglyceridaemia was induced in rats following the protocol: a fasting period of 22 h, 2 h of oral (p.o.) administration of 20% emulsion of longchain triglycerides (LCT emulsion), both repeated once. The plasma triglyceride and total cholesterol levels obtained 2 h after the protocol were 5.7 +/- 2.5 mmol/L (p < 0.0001 vs basal levels) and 1.7 +/- 0.3 mmol/L, respectively, n = 10. The new model was used to test the hypotriglyceridaemic effect of a single dose of Ficus carica (fig tree) leaf decoction administered i./p. (50 g dry wt/kg body wt). After the i.p. injection of serum saline (control group, n = 10) or Ficus carica extract (group A, n = 10), plasma triglyceride levels in the control group and group A were 5.9 +/- 2.9 mmol/L and 5.5 +/- 2.9 mmol/L just after the LCT emulsion protocol; 4.7 +/- 2.7 mmol/L and 0.9 +/- 0.4 mmol/L, p < 0.005, 60 min after the LCT protocol; and 3.6 +/- 2.9 mmol/L and 1.0 +/- 0.4 mmol/L, p < 0.05, 90 min after the LCT protocol. The plasma total cholesterol levels, which were not modified in our experimental model, showed no significant differences in relation to baseline levels in the presence or absence of Ficus carica treatment either. The clearly positive results suggest the presence in the fig leaf decoction of a compound or compounds that influence lipid catabolism.

P.87 Effect of an alpha-tocopherol supplementedMCT/LCT emulsion on the in vitro oxidizability of LDL+VLDL versus a conventional LCT emulsion in patients receiving TPN. A randomized double blind study

P.87 Effect of an alpha-tocopherol supplementedMCT/LCT emulsion on the in vitro oxidizability of LDL+VLDL versus a conventional LCT emulsion in patients receiving TPN. A randomized double blind study

Triglyceride hydrolysis of soy oil vs fish oil emulsions.

Fish oil triglycerides (TG) are being considered for use in IV lipid emulsions, but the characteristics of their lipase-mediated clearance from plasma are largely unknown. We compared the in vitro hydrolysis of soy oil long-chain triglyceride emulsions (LCT) and fish oil emulsions (omega-3) using lipoprotein (LPL) and hepatic (HL) lipases, omega-3 emulsions contained 18% and 28% of total TG fatty acid as eicosapentaenoic acid (EPA) and docosahexanoic acid (DHA), respectively. Under conditions of maximal hydrolysis, total free fatty acid (FFA) release was two- to threefold greater with LCT compared with omega-3 emulsions. Also, EPA and DHA together contributed proportionally much less than other fatty acids (< 20%) to FFA released from omega-3 emulsions. In mixtures of LCT emulsion with omega-3 emulsions, the presence of > 20% of omega-3 particles substantially inhibited LCT emulsion hydrolysis (by up to 50%). Our results suggest that, during infusion of omega-3 emulsions, EPA and DHA may enter cells as TG or partial glycerides within emulsion particles and not as FFA and that coinfusion of omega-3 emulsion with LCT emulsion at low omega-3:LCT emulsion ratios (up to 20% of total triglyceride as omega-3) will not substantially inhibit LCT hydrolysis.

Haemodynamic effects of a parenterally administered N-3 polyunsaturated fatty acid emulsion in conscious dogs

Clinical interest in Polyunsaturated fatty acid emulsion (PUFA) has increased since it has been reported to have beneficial effects on the progression of cardiovascular disease. [1], hypertension [2], the inflammatory response and sepsis [3]. Little data is available on the acute haemodynamic effects of these emulsions, hence, we compared the haemodynamic effects of a standard long chain triglyceride emulsion (LCT) with those of a 20% PUFA emulsion. Five mongrel dogs were chronically instrumented for the measurement of heart rate (HR), left atrial (LAP), aortic (ABP) and left ventricular pressure (LVP), LVdP/dt, coronary blood flow velocity (CBF), cardiac output (CO), systemic vascular resistance (SVR) and wall thickening fraction (WTF). All animals received PUFA and LCT (7 mL kg−1 on separate days. The lipids were given i.v. over 30 min as a continuous infusion. Full heparinisation was accomplished by i.v. administration of 200 IU kg−1 of heparin prior to the study. Serial haemodynamic measurements, at preset times, were performed over 2 h after the start of the infusion. All data were analysed with repeated measures ANOVA followed by Student's t-test. The LCT emulsion increased LVdP/dtmax from 1940±195 to 2220±246 mmHg sec−1 (P<0.05), while all other parameters did not change. In contrast, PUFA did not change LVdP/dt max and mean ABP, while WTF% (Fig. 1) and CO (3.39±0.18 to 2.75±0.18 L min−1; P<0.05) decreased significantly. HR (82±3.7 to 141±14 bpm; P<0.05) and SVR (2278±105 to 3095±214 dyn−1s−1cm−5; P<0.05) increased significantly. All parameters returned to baseline after 2 h. (Figure 2)Fig. 2: (abstract 2). Wall Thickening Fraction (WTF) presented as a % from control, during and after a PUFA and a LCT emulsion in conscious dogs. Data are presented as a mean±sem.* P<0.05 vs. control, ! P<0.05 vs. LCT. n=5.We conclude that a parenterally administered LCT emulsion has positive inotropic effects while an intravenous PUFA emulsion depresses cardiac function and increases SVR. The pathophysiological mechanism has not been elucidated, but our data suggests potentially detrimental effects for patients with limited cardiovascular reserve.