Oral Fat Intake Research Articles

Differential Patterns and Determinants of Cardiac Autonomic Nerve Dysfunction during Endotoxemia and Oral Fat Load in Humans.

The autonomic nervous system (ANS) plays an important role in regulating the metabolic homeostasis and controlling immune function. ANS alterations can be detected by reduced heart rate variability (HRV) in conditions like diabetes and sepsis. We determined the effects of experimental conditions mimicking inflammation and hyperlipidemia on HRV and heart rate (HR) in relation to the immune, metabolic, and hormonal responses resulting from these interventions. Sixteen lean healthy subjects received intravenous (i.v.) low-dose endotoxin (lipopolysaccharide [LPS]), i.v. fat, oral fat, and i.v. glycerol (control) for 6 hours, during which immune, metabolic, hormonal, and five HRV parameters (pNN50, RMSSD, low-frequency (LF) and high-frequency (HF) power, and LF/HF ratio) were monitored and energy metabolism and insulin sensitivity (M-value) were assessed. LPS infusion induced an increase (AUC) in HR and LF/HF ratio and decline in pNN50 and RMSSD, while oral fat resulted in elevated HR and a transient (hours 1-2) decrease in pNN50, RMSSD, and HF power. During LPS infusion, ΔIL-1ra levels and ΔIL-1ra and ΔIL-1ß gene expression correlated positively with ΔLF/HF ratio and inversely with ΔRMSSD. During oral fat intake, ΔGLP-1 tended to correlate positively with ΔHR and inversely with ΔpNN50 and ΔRMSSD. Following LPS infusion, lipid oxidation correlated positively with HR and inversely with pNN50 and RMSSD, whereas HRV was not related to M-value. In conclusion, suppression of vagal tone and sympathetic predominance during endotoxemia are linked to anti-inflammatory processes and lipid oxidation but not to insulin resistance, while weaker HRV changes in relation to the GLP-1 response are noted during oral fat load.Trial RegistrationClinicalTrials.gov NCT01054989

Long-term follow-up of children with congenital chylothorax

To the Editors: Congenital chylothorax, defined as the accumulation of lymphatic fluid in the pleural cavity, is a rare neonatal disorder. Nevertheless, congenital chylothorax represents the most common cause of pleural effusion in fetuses and newborns [1]. Due to the rarity of this disorder only a few case series are reported in the literature and current treatment recommendations are based on individual case reports or case series only [2–5]. The diagnosis of chylothorax is considered when pleural fluid triglyceride levels are >1.1 mmol·L−1 and total cell counts are >1,000 cells per mL with >80% lymphocytes. Without oral fat intake chylomicrons, which are often an indication for the diagnosis of chylothorax, are absent in the pleural fluid and distinction between chylous and non-chylous effusion might be difficult [6]. Long-term follow-up of children with congenital chylothorax, however, was documented in only four studies [7–10] and none included pulmonary function testing. We describe the clinical course and long-term outcome of infants with congenital chylothorax including neurodevelopmental follow-up and pulmonary function testing. In this study the data of all children who were documented in the local database of the Division of Neonatology (Paediatric Dept, Medical University of Graz, Graz, Austria) with the diagnosis of congenital chylothorax between January 1, 1995 and December …

Endothelial Microparticles (EMP) for the Assessment of Endothelial Function: An In Vitro and In Vivo Study on Possible Interference of Plasma Lipids

BackgroundCirculating endothelial microparticles (EMP) reflect the condition of the endothelium and are of increasing interest in cardiovascular and inflammatory diseases. Recently, increased numbers of EMP following oral fat intake, possibly due to acute endothelial injury, have been reported. On the other hand, the direct interference of lipids with the detection of EMP has been suggested. This study aimed to investigate the effect of lipid-rich solutions, commonly administered in clinical practice, on the detection, both in vitro and in vivo, of EMP.MethodsFor the in vitro assessment, several lipid-rich solutions were added to whole blood of healthy subjects (n = 8) and patients with coronary heart disease (n = 5). EMP (CD31+/CD42b−) were detected in platelet poor plasma by flow cytometry. For the in vivo study, healthy volunteers were evaluated on 3 different study-days: baseline evaluation, following lipid infusion and after a NaCl infusion. EMP quantification, lipid measurements and peripheral arterial tonometry were performed on each day.ResultsBoth in vitro addition and in vivo administration of lipids significantly decreased EMP (from 198.6 to 53.0 and from 272.6 to 90.6/µl PPP, respectively, p = 0.001 and p = 0.012). The EMP number correlated inversely with the concentration of triglycerides, both in vitro and in vivo (r = −0.707 and −0.589, p<0.001 and p = 0.021, respectively). The validity of EMP as a marker of endothelial function is supported by their inverse relationship with the reactive hyperemia index (r = −0.758, p = 0.011). This inverse relation was confounded by the intravenous administration of lipids.ConclusionThe confounding effect of high circulating levels of lipids, commonly found in patients that receive intravenous lipid-based solutions, should be taken into account when flow cytometry is used to quantify EMP.

Nutrient intake from habitual oral diet in patients with severe short bowel syndrome living in the southeastern United States

Objectives Little data are published on the habitual home oral diet of patients with short bowel syndrome (SBS). Methods We assessed nutrient intake from oral food and beverages in 19 stable patients with severe SBS who live in the southeastern United States. Intestinal absorption of energy, fat, nitrogen (N), and carbohydrate (CHO) was determined in a metabolic ward. Results We studied 12 women and 7 men, age 48 ± 3 y of age (mean ± SE) receiving parenteral nutrition for 31 ± 8 mo following massive small bowel resection (118 ± 25 cm residual small bowel). The patients demonstrated severe malabsorption of energy (59 ± 3% of oral intake), fat (41 ± 5%), N (42 ± 5%) and CHO (76 ± 3%). Oral energy intake was 2656 ± 242 kcal/d (39 ± 3 kcal/kg/d) and oral protein intake was 1.4 ± 0.1 g/kg/d. Food/beverage intake constituted 49 ± 4% of total (enteral plus parenteral) daily fluid intake, 66 ± 4% of total daily kcal and 58 ± 5% of total daily N intake. Oral fat intake averaged 92 ± 11 g/day (≈35% of total oral energy). Oral fluid intake averaged 2712 ± 240 ml/d, primarily from water, soft drinks, sweet tea and coffee. Simple sugars comprised 42 ± 3% of oral CHO intake. Usual dietary intake of multiple micronutrients were below the Recommended Dietary Allowances (RDA) in a large percentage of patients: vitamin A (47%), vitamin D (79%), vitamin E (79%), vitamin K (63%), thiamine (42%), vitamin B6 (68%), vitamin B12 (11%), vitamin C (58%), folate (37%), iron (37%), calcium (63%), magnesium (79%) and zinc (68%). Only seven patients (37%) were taking oral multivitamin-mineral supplements and only six subjects (32%) were taking oral iron and calcium supplements, respectively. Conclusion In these SBS patients, an oral diet provided a significant proportion of daily nutrient intake. The types of foods and fluids consumed are likely to worsen malabsorption and thus increase PN requirements. Oral intake of essential micronutrients was very low in a significant proportion of these individuals.

Traitement du chylothorax

Treatment of chylothorax remains insufficiently standardized. In the most resistant cases, treatment is dependent on the various aetiologies that disturb the normal management of the chyle within the thoracic duct. In fact, chylothorax results from a pleural chylous leak issuing from the thoracic duct or from one of its tributaries, or from those collateral lymphatic vessels that allow chyle derivation in case of abnormal function. This leak may be acquired following trauma, thoracic surgery, or various diagnostic or therapeutic medical procedures. It may appear spontaneously, due to rupture of chyle overloaded lymphatic vessels, with chyle back flowing into them from a pathological or malformed thoracic duct. Chylothorax is easily diagnosed by thoracocentesis but its mechanisms (status of the thoracic duct, valve insufficient tributaries, chyle derivation collaterals) may be studied only by lympho-angiography. Standard treatment is first medical: drainage, suppression of all oral fat intake, re-nutrition, treatment of the medical cause (such as cancer, thrombosis…) and use of products aimed at reducing chyle production. In case of therapeutic failure, surgery is required. Lympho-angiography is of paramount importance among the surgical strategy. Surgery may act on the leak itself : ligation (or embolization) of the thoracic duct, sutures of the leaking collaterals, or various other procedures. When the leaks are not evidenced, and when thoracic duct ligation is not indicated due to its “absence”, surgical treatment remains palliative, directed on the effusion itself: pleurodesis, derivation of the chyle (pleuroperitoneal shunt).

Chylothorax in Children: Guidelines for Diagnosis and Management

To establish guidelines for the diagnosis and management of chylothorax in children. Retrospective study. Fifty-one patients with a diagnosis of chylothorax. Twelve patients were excluded because of incomplete data or incorrect diagnosis. The following parameters were analyzed: triglyceride level, total cell number, and lymphocyte percentage; amount of pleural effusion on day of diagnosis, day 5, and day 14; and total time of pleural effusion. Prospectively, the same parameters were analyzed in a control group of 10 patients with pleural drainage. Patients with chylothorax were treated primarily with fat-free oral nutrition; if chyle did not stop, total parenteral nutrition with total enteric rest was started. If conservative therapy was not successful, pleurodesis was performed. In children with chylothorax triglyceride, triglyceride content ranged from 0.56 to 26.6 mmol/L; all values except one were > 1.1 mmol/L. In 36 of 39 patients (92%), the cell count was > 1,000 cells/microL. In 33 of 39 patients (85%), lymphocytes were > 90%. In patients without chylothorax triglyceride, triglyceride levels ranged from 0.1 to 0.71 mmol/L (median, 0.38 mmol/L) and cell count was from 20 to 1400 cells/microL (median, 322 cells/microL), with a maximum of 60% lymphocytes. With fat-free nutrition, chyle disappeared in 29 of 39 patients. Five patients died, and five required pleurodesis. Pleural effusion in children is chyle when it contains > 1.1 mmol/L triglycerides (with oral fat intake) and has a total cell count > or 1,000 cells/microL, with a lymphocyte fraction > 80%. Chylous effusions usually last long; however, after 6 weeks, the majority of the effusions (29 of 39 patients) had ceased. Late surgical interventions reduce the number of thoracotomies substantially, but can lead to very long hospitalization times. Early surgical interventions (after < 3 weeks) lead to a high number of thoracotomies, but certainly reduce hospitalization time.

Magnitude of alimentary lipemia is related to intima-media thickness of the common carotid artery in middle-aged men

Fat intake leads to generation of potentially atherogenic triglyceride-rich lipoproteins (TRL). To investigate the relationship between early atherosclerotic changes and accumulation of hepatic and intestinal TRL after oral fat intake, an estimate of the intima-media thickness (IMT) was made using ultrasound of the common carotid artery, and postprandial TRL was quantified during a standardized oral fat tolerance test in 30 healthy normo- and hypertriglyceridemic middle-aged men. At base line the expected positive association between the LDL cholesterol level and the IMT of the common carotid artery was observed ( r=0.53, P<0.01). In addition, postprandial plasma triglycerides, in particular those measured late (6 h) after intake of the test meal, correlated positively with the IMT ( r=0.44, P<0.05). Of note, this latter correlation was independent of both the LDL cholesterol and the fasting plasma triglyceride concentrations. In a multivariate analysis, 39% of the total variability for the common carotid IMT were explained by age, LDL cholesterol and the postprandial triglyceride level. In univariate analysis, few statistically significant relations were found between common carotid IMT and postprandial levels of chylomicron remnants, VLDL and VLDL remnants of different particle size, the latter determined by specific measurements of ApoB-48 and ApoB-100 in subfractions of TRL. Therefore, in healthy middle-aged men, elevated postprandial triglyceride levels might identify a metabolic state related to early atherosclerosis.

Endogenous triglyceride-rich lipoproteins accumulate in rat plasma when competing with a chylomicron-like triglyceride emulsion for a common lipolytic pathway

The rat liver secretes very low density lipoproteins (VLDL) containing either apoB-100 or apoB-48. After oral fat intake, chylomicrons containing apoB-48 and endogenously synthesized VLDL are mixed in the blood and the triglyceride clearance from these triglyceride-rich lipoprotein species compete for the same lipolytic pathway, i.e., lipoprotein lipase. A situation mimicking alimentary lipemia was induced by a short-term intravenous primed infusion of a chylomicron-like triglyceride emulsion to fed and fasted rats. The plasma concentration of apoB-100 and apoB-48 was monitored in triglyceride-rich lipoprotein subfractions after separation with density gradient ultracentrifugation by analytical SDS-PAGE. The net liver secretory output of VLDL was quantified by lipolytic blockade induced by Triton WR 1339. The chylomicron-like triglyceride emulsion induced a linear increase of large VLDL (Sf 60-400 subfraction containing both apoB-100 and apoB-48), almost to the same extent as that induced by Triton. The clearance of postprandial triglyceride-rich lipoproteins and both lipolysis and clearance of intravenously injected labeled rat chylomicrons was efficiently inhibited by the emulsion but not so complete as for fasting VLDL. The linearity of the VLDL increase and the very early response in the Intralipid-treated rats suggest that enhanced synthesis of VLDL is not a major cause for the accumulation. Rather, the present data indicate that a high plasma concentration of a chylomicron-like triglyceride emulsion competes efficiently with liver-derived VLDL for the same lipolytic pathway, which leads to accumulation in plasma of endogenous VLDL in the postprandial state.

Human intestinal alkaline phosphatase—release to the blood is linked to lipid absorption, but removal from the blood is not linked to lipoprotein clearance

To evaluate a possible quantitative relationship between the rise in intestinal alkaline phosphatase (IAP) activity and triglyceride-rich lipoproteins in the blood after an oral fat intake, a specific and sensitive immunocatalytic assay was used. First, day to day variation of the basal IAP activity in the blood of eight volunteers was evaluated. One group of subjects with high basal IAP activity and great variations from one day to the other was distinguished from a group with low basal IAP activity and small day to day variations. The subjects with high basal IAP activities were all secretors of red blood cell antigens, while those with low basal IAP activities were non-secretors. The IAP activity in the blood rose after fat rich meals but not after fat free meals. To further investigate this, IAP activities were measured in the blood of 28 men before 3, 6, 9 and 12 h after a standardized oral fat load of a mixed meal type. The activity rose in all individuals and showed a similar time course as the rise in plasma TG concentration. The elevations of the IAP activity were, however, not quantitatively correlated with the elevations in TG concentration, nor were there any relations in time to peak levels. Subjects with high basal IAP increased their IAP activity more than those with low basal IAP, but within neither group there was any correlation between the basal IAP activity and the rise in IAP activity. IAP did not float with lipoproteins on ultracentrifugation of plasma, nor did IAP bind to lipid droplets from a fat emulsion added to plasma.(ABSTRACT TRUNCATED AT 250 WORDS)

Solid-phase direct immunoassay for serum intestinal and placental alkaline phosphatase

Antibodies against placental alkaline phosphatase (PAP) share antigenic determinants with the intestinal isoenzyme (IAP) and vice versa. Both isoenzymes can be found as part of the total activity of alkaline phosphatase (AP) in the serum. Using antibody-coated polystyrene tubes, a simple and sensitive immunoassay was developed which allows the quantitative determination of IAP or PAP without interference of the cross-reacting isoenzyme. The presence and amount of IAP depends on the ABO blood group, secretory status and the oral fat intake. The serum IAP in healthy fasted individuals was found up to 8 U/I in secretors of blood group O and B and below 1 U/I in non-secretors and blood group A donors. In screening tests of various pathological sera. IAP was found elevated up to 100 U/I in idiopathic hyper-AP-aemia and some liver cirrhosis patients.

Plasma Fatty Acid Patterns of Bone Marrow Transplant Patients Primarily Supported by Fat‐Free Parenteral Nutrition

Oral food tolerance is compromised by drug and radiation therapy administered to patients undergoing bone marrow transplantation for hematological malignancy or aplastic anemia. Resultant decreases in oral fat intake coincident with fat-free parenteral nutrition may predispose patients to essential fatty acid (EFA) deficiency. Determinations were made of the fatty acid composition of plasma total lipid from 20 bone marrow transplant patients on admission, at the time of bone marrow transplant, and on days 7, 14, 30, and 60 post-bone marrow transplant. Patients ate ad libitum but with little appetite and received fat-free parenteral nutrition interrupted for numerous blood product and drug infusions. Abnormal EFA status was manifest (20:3 omega 9/20:4 ratio greater than 0.2) in 12 of 20 patients during the course of treatment. Plasma EFA status was consistently correlated with oral fat intake but not with sex, age, percentage of ideal body weight, or amount of plasma infused. This suggests that dietary fat was absorbed limiting the severity of EFA deficiency. Interruptions of glucose infusion averaging only about 2 hours/day, also may have helped moderate the deficiency.

Faecal fat excretion, diarrhea, and subjective complaints with highly dosed oral fat intake.

Healthy subjects received a diet with a constant content of protein, fat, minerals and vitamins. To this diet were added increasing amounts of fat in the form of corn oil and olive oil up to a maximum

Studies on Endogenous Lipolytic Activity upon the Oral Fat Loading in Atherosclerotic Diseases

The disturbance of lipid metabolism has been regarded as one of the important factor in the etiology of atherosclerosis. It is thought that the ability to remove rapidly the absorbed fat from the blood stream is important to prevent the development of atherosclerosis. From this point of view, following observations were carried out. Method The subjects of observation were divided into three groups. Group I consisted of 10 young and healthy persons, group II of 18 aged patients with atherosclerotic diseases and group III of 6 old and clinically normal persons. To these subjects 100 gm of raw oream which contained 25% of fat was orally given early morning after overnight fasting. Then the blood samples were taken immediately before and 30 min., 1, 2, 4, 6, 8 hours after fat intake. Plasma separated from these samples were supplied to determine the optical density and the endogenous lipolytic activity. In each samples, the optical density (O.D.) was measured by the electro-spectrophotometer and the endogenous lipolytic activity (E.L.A.) was determined by the difference of content of nonesterified fatty acid (NEFA) prior to and after the incubation of each plasma at 37°C for 60 min.. NEFA content in plasma were measured by the Dole's method and indicated by rEq/ 1. Sometimes, NEFA content in plasma were observed to decrease and in such cases the E.L.A. were indicated by minus values. Result 1) Variations of O.D. in plasma following the oral fat loading The O.D. value of all cases in each group were increased following the oral fat intake and then gradually decreased after reaching to its maximal value. The differences of maximal value of O.D. among three group were not significant. It was observed, on the other hand, that O.D. was delayed in group II to reach its peak and also to recover from its peak compared with the other groups. 2) Variations of NEFA in plasma following the oral fat loading. NEFA content in plasma was gradually increased after the administration of fat in each group, but the obvious differences were not found in the degree of increase among three group. 3) Variations of E.L.A. in plasma following the oral fat loading. A certain degree of E.L.A. was occasionally demonstrated even before the fat intake in each group and mean value of them were 166, 57 and 100 respectively, but there were no significant differences among three group, because its variations were considerably wide. On the other hand, differences of E.L.A. patterns among three groups were very significant. Most cases of group I revealed their E.L.A. increased at the time from 30 min. to two hours after the fat intake and then gradually decreased, but not the minus values. On the contrary, there was few cases in group II, which showed a initial elevation of E.L.A. and many cases of this group indicated the remarkable depression of their activity and frequently showed the minus values of them. E.L.A. pattern in group III showed the mid-type of the other two groups. From these results it is demonstrated that E.L.A. in atherosclerotic patients hardly increase after oral fat intake, then markedly depress and is apt to show minus value compared with control groups. 4) Correlation between the pattern in O.D. and E.L.A. The pattern in O.D. were divided into two types, that is, normal type and delayed type. The former showed its peak within 4 hours after fat intake and the latter showed its peak later than 6 hours after fat intake. Most cases in group I showed normal type in O.D. and plus activity in E.L.A. 4 hours after fat intake. However, in group II, most cases showed delayed type in O.D. and minus activity in E.L.A. 4 hours after fat intake. The pattern in O.D. were also divided into normal and delayed type by the degree of recovery from its peak in two hours. In normal type the O.D. [the rest omitted]

In vitro studies of human plasma lipolytic activity before and after oral fat intake.

The rate of in vitro lipolysis of added human low density lipoproteins was determined in 22 normal individuals using fasting and lipemic plasma. Unesterified fatty acid release was found in 16 subjects in all, in 10 in the fasting plasma and in 14 in the postlipemic plama. Lipolytic activity was greater in the lipemic sample in eight of the 16 individuals, in three it was unchanged before or after fat intake, and in five it was higher in the fasting sample. Addition of deoxycholate, which decreases heparin clearing factor and increases pancreatic lipase activity, inhibited lipolysis in most of the subjects and increased it in a few. Studies using beta-naphthol laurate, which in the presence of taurocholate is an excellent substrate for human pancreatic lipase but not for postheparin lipolytic activity, showed no hydrolysis in eight subjects, in six of whom lipolysis of the lipoproteins occurred. The results of the study suggest that increased plasma lipolytic activity is sometimes present after the ingestion of fat. They further indicate that endogenous heparin lipoprotein lipase is the major plasma enzyme involved in the splitting of neutral fat, but that a lipase similar to pancreatic lipase may be present less frequently, in small amounts, and may require added bile for activity. Submitted on February 20, 1957