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Lee TH, Hoover RL, Williams JD, Sperling RI, Ravalese J, Spur BW, Robinson DR, Corey EJ, Lewis RA, Austen KF. Effect of dietary enrichment with eicosapentaenoic and docosahexaenoic acids on in vitro neutrophil and monocyte leukotriene generation and neutrophil function. N Engl J Med 1985; 312:1217-24. [PMID: 2985986 DOI: 10.1056/nejm198505093121903] [Citation(s) in RCA: 913] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The effects of dietary fish-oil fatty acids on the function of the 5-lipoxygenase pathway of peripheral-blood polymorphonuclear leukocytes and monocytes were determined in seven normal subjects who supplemented their usual diet for six weeks with daily doses of triglycerides containing 3.2 g of eicosapentaenoic acid and 2.2 g of docosahexaenoic acid. The diet increased the eicosapentaenoic acid content in neutrophils and monocytes more than sevenfold, without changing the quantities of arachidonic acid and docosahexaenoic acid. When the neutrophils were activated, the release of [3H]arachidonic acid and its labeled metabolites was reduced by a mean of 37 per cent, and the maximum generation of three products of the 5-lipoxygenase pathway was reduced by more than 48 per cent. The ionophore-induced release of [3H]arachidonic acid and its labeled metabolites from monocytes in monolayers was reduced by a mean of 39 per cent, and the generation of leukotriene B4 by 58 per cent. The adherence of neutrophils to bovine endothelial-cell monolayers pretreated with leukotriene B4 was inhibited completely, and their average chemotactic response to leukotriene B4 was inhibited by 70 per cent, as compared with values determined before the diet was begun and six weeks after its discontinuation. We conclude that diets enriched with fish-oil-derived fatty acids may have antiinflammatory effects by inhibiting the 5-lipoxygenase pathway in neutrophils and monocytes and inhibiting the leukotriene B4-mediated functions of neutrophils.
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Fachi JL, Felipe JDS, Pral LP, da Silva BK, Corrêa RO, de Andrade MCP, da Fonseca DM, Basso PJ, Câmara NOS, de Sales E Souza ÉL, Dos Santos Martins F, Guima SES, Thomas AM, Setubal JC, Magalhães YT, Forti FL, Candreva T, Rodrigues HG, de Jesus MB, Consonni SR, Farias ADS, Varga-Weisz P, Vinolo MAR. Butyrate Protects Mice from Clostridium difficile-Induced Colitis through an HIF-1-Dependent Mechanism. Cell Rep 2020; 27:750-761.e7. [PMID: 30995474 DOI: 10.1016/j.celrep.2019.03.054] [Citation(s) in RCA: 241] [Impact Index Per Article: 48.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 01/17/2019] [Accepted: 03/13/2019] [Indexed: 02/06/2023] Open
Abstract
Antibiotic-induced dysbiosis is a key factor predisposing intestinal infection by Clostridium difficile. Here, we show that interventions that restore butyrate intestinal levels mitigate clinical and pathological features of C. difficile-induced colitis. Butyrate has no effect on C. difficile colonization or toxin production. However, it attenuates intestinal inflammation and improves intestinal barrier function in infected mice, as shown by reduced intestinal epithelial permeability and bacterial translocation, effects associated with the increased expression of components of intestinal epithelial cell tight junctions. Activation of the transcription factor HIF-1 in intestinal epithelial cells exerts a protective effect in C. difficile-induced colitis, and it is required for butyrate effects. We conclude that butyrate protects intestinal epithelial cells from damage caused by C. difficile toxins via the stabilization of HIF-1, mitigating local inflammatory response and systemic consequences of the infection.
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Research Support, Non-U.S. Gov't |
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241 |
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Flatt JP, Ravussin E, Acheson KJ, Jéquier E. Effects of dietary fat on postprandial substrate oxidation and on carbohydrate and fat balances. J Clin Invest 1985; 76:1019-24. [PMID: 3900133 PMCID: PMC423974 DOI: 10.1172/jci112054] [Citation(s) in RCA: 240] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
To study the effect of dietary fat on postprandial substrate utilization and nutrient balance, respiratory exchange was determined in seven young men for 1 h before and 9 h after the ingestion of one of three different breakfasts: i.e., bread, jam, and dried meat (482 kcal: 27% protein, 62% carbohydrate, and 11% fat); bread, jam, and dried meat plus 50 g of margarine containing long-chain triglycerides (LCT); or bread, jam, and dried meat plus 40 g medium-chain triglycerides (MCT) and 10 g LCT margarine (858 kcal: 15% protein, 35% carbohydrate, and 50% fat). Plasma glucose concentrations peaked 45 min after the start of the meals. When compared with the low fat meal, the LCT margarine supplement had no effect at any time on circulating glucose and insulin concentrations, nor on the respiratory quotient. When MCTs were consumed, plasma glucose and insulin concentrations remained lower and plasma FFA concentrations higher during the first 2 h. 9 h after the breakfasts, the amounts of substrates oxidized were similar in each case, i.e., approximately 320, 355, and 125 kcal for carbohydrate, fat, and protein, respectively. This resulted in comparable carbohydrate (mean +/- SD = -22 +/- 32, -22 +/- 37, and -24 +/- 22 kcal) and protein balances (-7 +/- 9, +7 +/- 7, and -8 +/- 11 kcal) after the low fat, LCT- and MCT-supplemented test meals, respectively. However, after the low fat meal, the lipid balance was negative (-287 +/- 60 kcal), which differed significantly (P less than 0.001) from the fat balances after the LCT- and MCT-supplemented meals, i.e., +60 +/- 33 and +57 +/- 25 kcal, respectively. The results demonstrate that the rates of fat and of carbohydrate oxidation are not influenced by the fat content of a meal.
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Maki KC, Davidson MH, Tsushima R, Matsuo N, Tokimitsu I, Umporowicz DM, Dicklin MR, Foster GS, Ingram KA, Anderson BD, Frost SD, Bell M. Consumption of diacylglycerol oil as part of a reduced-energy diet enhances loss of body weight and fat in comparison with consumption of a triacylglycerol control oil. Am J Clin Nutr 2002; 76:1230-6. [PMID: 12450887 DOI: 10.1093/ajcn/76.6.1230] [Citation(s) in RCA: 225] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Diacylglycerol is a natural component of edible oils that has metabolic characteristics that are distinct from those of triacylglycerol. OBJECTIVE We assessed the efficacy of an oil containing mainly 1,3-diacylglycerol in reducing body weight and fat mass when incorporated into a reduced-energy diet. DESIGN The study was a randomized, double-blind, parallel intervention trial that was conducted at an outpatient clinical research center. The subjects (n = 131) were overweight or obese men (waist circumference > or = 90 cm) and women (waist circumference > or = 87 cm). Food products (muffins, crackers, soup, cookies, and granola bars) containing diacylglycerol or triacylglycerol oil and having the same fatty acid composition were incorporated into a reduced-energy diet (2100-3350-kJ/d deficit) for 24 wk. Percentages of change in body weight, fat mass, and intraabdominal fat area were assessed. RESULTS In an intention-to-treat analysis, body weight and fat mass decreased significantly more in the diacylglycerol group than in the triacylglycerol group (P = 0.025 and 0.037, respectively). By the end of the trial, mean body weight had decreased 3.6% and 2.5% in the diacylglycerol and triacylglycerol groups, respectively. Fat mass decreased 8.3% and 5.6% in the diacylglycerol and triacylglycerol groups, respectively. CONCLUSION Foods containing diacylglycerol oil promoted weight loss and body fat reduction and may be useful as an adjunct to diet therapy in the management of obesity.
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Clinical Trial |
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225 |
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Nagao T, Watanabe H, Goto N, Onizawa K, Taguchi H, Matsuo N, Yasukawa T, Tsushima R, Shimasaki H, Itakura H. Dietary diacylglycerol suppresses accumulation of body fat compared to triacylglycerol in men in a double-blind controlled trial. J Nutr 2000; 130:792-7. [PMID: 10736331 DOI: 10.1093/jn/130.4.792] [Citation(s) in RCA: 213] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We examined the effects of the long-term ingestion of dietary diacylglycerols (DG) in a double-blind controlled study of human lipid metabolism. Healthy men (n = 38; aged from 27 to 49 y, body mass index (BMI) ranging from 21.8 to 27.4 kg/m(2)) completed the study. To accustom the subjects to the test diets prior to the experiment, they were supplied with test diets of triacylglycerol (TG) oil for 4 wk (control period). The test oils (10 g/d) were included in bread, mayonnaise or shortbread and served for the breakfast. The target for total lipid intake was 50 g/d (15 g for breakfast, 15 g for lunch and 20 g for dinner) throughout the study. The subjects were then divided into two groups so that mean BMI and the hepatic fat content, determined by computed tomography, for each group were not different. One group (DG group) consumed test meals containing DG-rich oil (10 g/d) while the other group (TG group) consumed the same meal as during the control period. Ten grams of the DG-rich oil contained 5.5 g 1,3-DG, 2.5 g 1,2-DG and 2 g TG. The actual lipid intake during the study was 43 g/d. Body weight, BMI and waist circumference decreased in both groups at the end of the test period of 16 wk. However, the magnitudes of decreases in these variables were significantly greater in the DG group than in the TG group. Decreases of total fat, visceral fat area and subcutaneous fat area of the abdominal traverse images of computed tomography in the DG group were also significantly greater than those in the TG group. Hepatic fat content decreased significantly in the DG group while no change was observed in the TG group. Serum lipid concentrations (TG, total cholesterol, free fatty acid) and related metabolites (glucose, insulin, total ketone body) did not change significantly in either group. Thus, in contrast to TG, DG apparently suppressed accumulation of fat and possibly reduces the risk of diseases associated with visceral fat obesity.
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Clinical Trial |
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Nebeling LC, Miraldi F, Shurin SB, Lerner E. Effects of a ketogenic diet on tumor metabolism and nutritional status in pediatric oncology patients: two case reports. J Am Coll Nutr 1995; 14:202-8. [PMID: 7790697 DOI: 10.1080/07315724.1995.10718495] [Citation(s) in RCA: 205] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVE Establish dietary-induced ketosis in pediatric oncology patients to determine if a ketogenic state would decrease glucose availability to certain tumors, thereby potentially impairing tumor metabolism without adversely affecting the patient's overall nutritional status. DESIGN Case report. SETTING University Hospitals of Cleveland. SUBJECTS Two female pediatric patients with advanced stage malignant Astrocytoma tumors. INTERVENTIONS Patients were followed as outpatients for 8 weeks. Ketosis was maintained by consuming a 60% medium chain triglyceride oil-based diet. MAIN OUTCOME MEASURES Tumor glucose metabolism was assessed by Positron Emission Tomography (PET), comparing [Fluorine-18] 2-deoxy-2-fluoro-D-glucose (FDG) uptake at the tumor site before and following the trial period. RESULTS Within 7 days of initiating the ketogenic diet, blood glucose levels declined to low-normal levels and blood ketones were elevated twenty to thirty fold. Results of PET scans indicated a 21.8% average decrease in glucose uptake at the tumor site in both subjects. One patient exhibited significant clinical improvements in mood and new skill development during the study. She continued the ketogenic diet for an additional twelve months, remaining free of disease progression. CONCLUSION While this diet does not replace conventional antineoplastic treatments, these preliminary results suggest a potential for clinical application which merits further research.
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Case Reports |
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Nishi Y, Hiejima H, Hosoda H, Kaiya H, Mori K, Fukue Y, Yanase T, Nawata H, Kangawa K, Kojima M. Ingested medium-chain fatty acids are directly utilized for the acyl modification of ghrelin. Endocrinology 2005; 146:2255-64. [PMID: 15677766 DOI: 10.1210/en.2004-0695] [Citation(s) in RCA: 191] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Ghrelin, an acylated brain and gut peptide, is primarily produced by endocrine cells of the gastric mucosa for secretion into the circulation. The major active form of ghrelin is a 28-amino-acid peptide containing an n-octanoyl modification at serine that is essential for activity. Studies have identified multiple physiological functions for ghrelin, including GH release, appetite stimulation, and metabolic fuel preference. Until now, there has not been any report detailing the mechanism of ghrelin acyl modification. Here we report that ingestion of either medium-chain fatty acids (MCFAs) or medium-chain triacylglycerols (MCTs) increased the stomach concentrations of acylated ghrelin without changing the total (acyl- and des-acyl-) ghrelin amounts. After ingestion of either MCFAs or MCTs, the carbon chain lengths of the acyl groups attached to nascent ghrelin molecules corresponded to that of the ingested MCFAs or MCTs. Ghrelin peptides modified with n-butyryl or n-palmitoyl groups, however, could not be detected after ingestion of the corresponding short-chain or long-chain fatty acids, respectively. Moreover, n-heptanoyl ghrelin, an unnatural form of ghrelin, could be detected in the stomach of mice after ingestion of either n-heptanoic acid or glyceryl triheptanoate. These findings indicate that ingested medium-chain fatty acids are directly used for the acylation of ghrelin.
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Huo T, Ferruzzi MG, Schwartz SJ, Failla ML. Impact of fatty acyl composition and quantity of triglycerides on bioaccessibility of dietary carotenoids. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2007; 55:8950-8957. [PMID: 17927194 DOI: 10.1021/jf071687a] [Citation(s) in RCA: 171] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A carotenoid-rich salad meal with varying amounts and types of triglycerides (TG) was digested using simulated gastric and small intestinal conditions. Xanthophylls (lutein and zeaxanthin) and carotenes (alpha-carotene, beta-carotene, and lycopene) in chyme and micelle fraction were quantified to determine digestive stability and efficiency of micellarization (bioaccessibility). Micellarization of lutein (+zeaxanthin) exceeded that of alpha- and beta-carotenes, which was greater than that of lycopene for all test conditions. Micellarization of carotenes, but not lutein (+zeaxanthin), was enhanced (P < 0.05) by addition of TG (2.5% v/w) to the meal and was dependent on fatty acyl chain length in structured TG (c18:1 > c8:0 > c4:0). The degree of unsaturation of c18 fatty acyl chains in TG added to the salad purée did not significantly alter the efficiency of micellarization of carotenoids. Relatively low amounts of triolein and canola oil (0.5-1%) were required for maximum micellarization of carotenes, but more oil (approximately 2.5%) was required when TG with medium chain saturated fatty acyl groups (e.g., trioctanoin and coconut oil) was added to the salad. Uptake of lutein and beta-carotene by Caco-2 cells also was examined by exposing cells to micelles generated during the simulated digestion of salad purée with either triolein or trioctanoin. Cell accumulation of beta-carotene was independent of fatty acyl composition of micelles, whereas lutein uptake was slightly, but significantly, increased from samples with digested triolein compared to trioctanoin. The results show that the in vitro transfer of alpha-carotene, beta-carotene, and lycopene from chyme to mixed micelles during digestion requires minimal (0.5-1%) lipid content in the meal and is affected by the length of fatty acyl chains but not the degree of unsaturation in TG. In contrast, fatty acyl chain length has limited if any impact on carotenoid uptake by small intestinal epithelial cells. These data suggest that the amount of TG in a typical meal does not limit the bioaccessibility of carotenoids.
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Porter CJH, Kaukonen AM, Taillardat-Bertschinger A, Boyd BJ, O'Connor JM, Edwards GA, Charman WN. Use of in vitro lipid digestion data to explain the in vivo performance of triglyceride-based oral lipid formulations of poorly water-soluble drugs: studies with halofantrine. J Pharm Sci 2004; 93:1110-21. [PMID: 15067688 DOI: 10.1002/jps.20039] [Citation(s) in RCA: 168] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The relative oral bioavailability (BA) of halofantrine base (Hf) was assessed in male beagle dogs after administration of a medium chain triglyceride (MCT), a long chain triglyceride (LCT), and a blended LCT/MCT lipid solution formulation of Hf (Study 1) and after administration of suspensions of Hf base and Hf. HCl in LCT (Study 2). A series of in vitro lipid digestion experiments were also performed in an attempt to clarify the data obtained. In vitro drug solubilization profiles were markedly dependent on the mass of lipid employed in lipid digestion experiments. At high lipid masses ( approximately 25 mg triglyceride/mL), MCT formulations gave maximal benefit, whereas at low lipid concentrations ( approximately 5 mg triglyceride/mL), LCT formulations provided improved solubilization capacity. The in vitro digestion and solubilization data at lower lipid masses were consistent with the in vivo data where the BA of Hf after oral administration of the LCT solution > LCT/MCT blend > MCT solution. The second BA study showed similar, albeit variable, exposure after oral administration of a suspension of Hf base or Hf. HCl in LCT and this trend was broadly consistent with in vitro results. This study demonstrates the potential utility of in vitro digestion models to assess and rank order the in vivo performance of lipid solution and suspension formulations of poorly water-soluble drugs such as Hf.
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Comparative Study |
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Abstract
Major advances in the understanding of the aetio-pathogenesis and genetics of inflammatory bowel disease have been accompanied by an escalation in the sophistication of immunomodulatory inflammatory bowel disease therapeutics. However, the basic 'triple' therapy (5-aminosalicylates, corticosteroids, azathioprine) and nutrition have maintained their central role in the management of patients with inflammatory bowel disease over recent decades. This review provides an overview of the supportive and therapeutic perspectives of nutrition in adult inflammatory bowel disease. The objective of supportive nutrition is to correct malnutrition in terms of calorie intake or specific macro- or micronutrients. Of particular clinical relevance is deficiency in calcium, vitamin D, folate, vitamin B12 and zinc. There is justifiably a growing sense of unease amongst clinicians and patients with regard to the long-term use of corticosteroids in inflammatory bowel disease. This, rather than arguments about efficacy, should be the catalyst for revisiting the use of enteral nutrition as primary treatment in Crohn's disease. Treatment failure is usually related to a failure to comply with enteral nutrition. Potential factors that militate against successful completion of enteral nutrition are feed palatability, inability to stay on a solid-free diet for weeks, social inconvenience and transient feed-related adverse reactions. Actions that can be taken to improve treatment outcome include the provision of good support from dietitians and clinicians for the duration of treatment and the subsequent 'weaning' period. There is evidence to support a gradual return to a normal diet through exclusion-re-introduction or other dietary regimen following the completion of enteral nutrition to increase remission rates. We also review the evidence for emerging therapies, such as glutamine, growth factors and short-chain fatty acids. The future may see the evolution of enteral nutrition into an important therapeutic strategy, and the design of a 'Crohn's disease-specific formulation' that is individually tailored, acceptable to patients, cost-effective, free from adverse side-effects and combines enteral nutrition with novel pre- and pro-biotics and other factors.
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Review |
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168 |
11
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Tsuji H, Kasai M, Takeuchi H, Nakamura M, Okazaki M, Kondo K. Dietary medium-chain triacylglycerols suppress accumulation of body fat in a double-blind, controlled trial in healthy men and women. J Nutr 2001; 131:2853-9. [PMID: 11694608 DOI: 10.1093/jn/131.11.2853] [Citation(s) in RCA: 161] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We investigated the effect of long-term ingestion of dietary medium-chain triacylglycerols (MCT) on body weight and fat in humans. Using a double-blind, controlled protocol, we assessed the potential health benefits of MCT compared with long-chain triacylglycerols (LCT) in 78 healthy men and women [body mass index (BMI) > or = 23 kg/m(2): n = 26 (MCT), n = 30 (LCT); BMI < 23 kg/m(2): n = 15 (MCT), n = 7 (LCT)]. Changes in anthropometric variables, body weight and body fat during the 12-wk MCT treatment period were compared with those in subjects consuming the LCT diet. The subjects were asked to consume 9218 kJ/d and 60 g/d of total fat. The energy, fat, protein and carbohydrate intakes did not differ significantly between the groups. Body weight and body fat in both groups had decreased by wk 4, 8 and 12 of the study. However, in the subjects with BMI > or = 23 kg/m(2), the extent of the decrease in body weight was significantly greater in the MCT group than in the LCT group. In subjects with BMI > or = 23 kg/m(2), the loss of body fat in the MCT group (-3.86 +/- 0.3 kg) was significantly greater than that in the LCT group (-2.75 +/- 0.2 kg) at 8 wk. In addition, in subjects with BMI > or = 23 kg/m(2), the decrease in the area of subcutaneous fat in the MCT group was significantly greater than that in the LCT group at wk 4, 8 and 12. These results suggest that the MCT diet may reduce body weight and fat in individuals (BMI > or = 23 kg/m(2)) more than the LCT diet.
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Clinical Trial |
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161 |
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Seidner DL, Mascioli EA, Istfan NW, Porter KA, Selleck K, Blackburn GL, Bistrian BR. Effects of long-chain triglyceride emulsions on reticuloendothelial system function in humans. JPEN J Parenter Enteral Nutr 1989; 13:614-9. [PMID: 2519758 DOI: 10.1177/0148607189013006614] [Citation(s) in RCA: 156] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Parenteral administration of long-chain triglyceride emulsions has been shown to have deleterious effects on reticuloendothelial system function in animal models. It is unknown whether this interference occurs in humans with clinically relevant doses of intravenous fat. Two studies were done. Eighteen patients were prospectively enrolled for study. Patients received full feeding by continuous total parenteral nutrition (amino acids 1.5 g/kg/day and dextrose 4.5 g/kg/day) with 33.1 kcal/kg/day. Forty-three % of the nonprotein calories were provided as soybean oil emulsion (Travamulsion 20%) and was administered intravenously over 10 hr (0.130 g/kg/hr). Reticuloendothelial system function was determined by measuring the change in the clearance rate of intravenously injected 99mTc-sulfur colloid (TSC) in each patient. In study 1 (n = 10), one day of lipid (10 hr) was infused, with the clearance of 99mTc-sulfur colloid measured before the lipid was infused and then during the last hour of the 10-hr infusion. In study 2 (n = 8), the clearance rates were measured before the lipid emulsion was begun, and then during the last hour of the infusion on the 3rd day. Clearance rates for TSC after 10 hr of lipid infusion in study 1 did not differ (0.27 +/- 1/min to 0.26 +/- 0.1/min, p greater than 0.10). However, after 3 days of lipid infusion (10 hr/day), a statistically significant reduction in TSC was seen (0.46 +/- 0.08/min-0.27 +/- 0.03/min, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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Paolisso G, Gambardella A, Amato L, Tortoriello R, D'Amore A, Varricchio M, D'Onofrio F. Opposite effects of short- and long-term fatty acid infusion on insulin secretion in healthy subjects. Diabetologia 1995; 38:1295-9. [PMID: 8582538 DOI: 10.1007/bf00401761] [Citation(s) in RCA: 142] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Our study investigates short- and long-term effects of infusion of non-esterified fatty acids (NEFA) on insulin secretion in healthy subjects. Twelve healthy individuals underwent a 24-h Intralipid (10% triglyceride emulsion) infusion at a rate of 0.4 ml/min with a simultaneous infusion of heparin (a bolus of 200 U followed by 0.2 U/min per kg body weight). After an overnight fast (baseline), at 6 and at 24 h of Intralipid infusion and 24 h after Intralipid discontinuation (recovery test), all subjects underwent an intravenous glucose tolerance test (iv-GTT) (25 g of glucose/min). Intralipid infusion caused a threefold rise in plasma NEFA concentrations with no difference between the 6- and the 24-h concentrations. Compared to baseline acute insulin response (AIR) (AIR = 63 +/- 8 mU/l), short-term (6-h) Intralipid infusion was associated with a significant increase in AIR (86 +/- 12 mU/l p < 0.01); in contrast, long-term (24-h) Intralipid delivery was associated with inhibition of AIR (31 +/- 5 mU/l) compared to baseline (p < 0.001) and to the 6-h (p < 0.03) triglyceride emulsion infusion. Intralipid infusion was associated with a progressive and significant decline in respiratory quotient (RQ). A positive correlation between changes in fasting plasma NEFA concentrations and AIR at the 6-h infusion (r = 0.89 p < 0.001) was found. In contrast, at the end of the Intralipid infusion period, changes in plasma NEFA concentrations and AIR were negatively correlated (r = -0.87 p < 0.001). The recovery test showed that fasting plasma NEFA concentrations, RQ and AIR had returned to baseline values. In the control study (n = 8) 0.9% NaCl infusion did not mimick the effect of Intralipid. In conclusion, our study demonstrates that short- and long-term exposures of beta cells to high plasma NEFA concentrations have opposite effects on glucose-induced insulin secretion.
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Clinical Trial |
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142 |
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Kennedy K, Fewtrell MS, Morley R, Abbott R, Quinlan PT, Wells JC, Bindels JG, Lucas A. Double-blind, randomized trial of a synthetic triacylglycerol in formula-fed term infants: effects on stool biochemistry, stool characteristics, and bone mineralization. Am J Clin Nutr 1999; 70:920-7. [PMID: 10539755 DOI: 10.1093/ajcn/70.5.920] [Citation(s) in RCA: 141] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The low sn-2 palmitate content of infant formulas results in formation of fatty acid calcium soaps in the stools and reduced calcium absorption. OBJECTIVE Our objective was to test the hypotheses that increasing the proportion of sn-2 palmitate in formula for term infants would result in greater skeletal mineral deposition and reduced stool hardness. DESIGN Healthy term neonates were randomly assigned to receive standard formula (n = 103) or formula containing 50% sn-2 palmitate (high-sn-2 formula; n = 100) for 12 wk. One hundred twenty breast-fed infants were also studied. The main outcome measures were 1) radial (single-photon absorptiometry) and whole-body (dual-energy X-ray absorptiometry) bone mineral content (WBBMC) at 12 wk and 2) stool frequency, volume, and consistency at 6 and 12 wk. Secondary outcome measures included stool fatty acid content. RESULTS Infants receiving high-sn-2 formula had higher WBBMC (128.1 +/- 9.7 compared with 122.7 +/- 10.1 g, adjusted for size and sex), softer stools at 6 and 12 wk, and a lower proportion of stool soap fatty acids than did infants receiving the control formula. Breast-fed infants had adjusted WBBMC values (128.3 +/- 9.1 g) similar to those of infants fed high-sn-2 formula and significantly higher than those of infants fed the control formula. CONCLUSIONS Changing the stereoisomeric structure of palmitate in infant formula resulted in higher WBBMC, reduced stool soap fatty acids, and softer stools more like those of breast-fed infants. The greater bone mass measured could be important if it persists beyond the trial period; this merits further investigation.
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Clinical Trial |
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141 |
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Özbudak EM, Lewis J. Notch signalling synchronizes the zebrafish segmentation clock but is not needed to create somite boundaries. PLoS Genet 2008; 4:e15. [PMID: 18248098 PMCID: PMC2222926 DOI: 10.1371/journal.pgen.0040015] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2007] [Accepted: 12/11/2007] [Indexed: 01/03/2023] Open
Abstract
Somite segmentation depends on a gene expression oscillator or clock in the posterior presomitic mesoderm (PSM) and on read-out machinery in the anterior PSM to convert the pattern of clock phases into a somite pattern. Notch pathway mutations disrupt somitogenesis, and previous studies have suggested that Notch signalling is required both for the oscillations and for the read-out mechanism. By blocking or overactivating the Notch pathway abruptly at different times, we show that Notch signalling has no essential function in the anterior PSM and is required only in the posterior PSM, where it keeps the oscillations of neighbouring cells synchronized. Using a GFP reporter for the oscillator gene her1, we measure the influence of Notch signalling on her1 expression and show by mathematical modelling that this is sufficient for synchronization. Our model, in which intracellular oscillations are generated by delayed autoinhibition of her1 and her7 and synchronized by Notch signalling, explains the observations fully, showing that there are no grounds to invoke any additional role for the Notch pathway in the patterning of somite boundaries in zebrafish. The somites—the embryonic segments of the vertebrate body—form one after another from tissue at the tail end of the embryo. A gene expression oscillator, the somite segmentation clock, operating in this tail region, marks out a periodic spatial pattern and so controls the segmentation process. Evidence from mutants shows that the Notch cell-cell signalling pathway has a critical role in the clock mechanism. However, when we switch on a blockade of Notch signalling, by immersing zebrafish embryos in the chemical inhibitor DAPT, the next ∼12 somites form normally, and only after that do disrupted somites appear. We show that this is because Notch signalling is needed only to maintain synchrony between the clocks of individual cells. The cells take about seven cycles to drift out of synchrony when Notch-mediated communication is blocked, and then a further five cycles to pass from the site where the tissue receives its “time-stamp” to the site where overt segmentation begins. By mathematical modelling, backed up with measurements on transgenic embryos, we show how Notch signalling may act at a molecular level to synchronise the intracellular oscillators of adjacent individual cells.
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Research Support, Non-U.S. Gov't |
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Szentirmai É, Millican NS, Massie AR, Kapás L. Butyrate, a metabolite of intestinal bacteria, enhances sleep. Sci Rep 2019; 9:7035. [PMID: 31065013 PMCID: PMC6504874 DOI: 10.1038/s41598-019-43502-1] [Citation(s) in RCA: 135] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 04/25/2019] [Indexed: 12/17/2022] Open
Abstract
Emerging evidence suggests that the intestinal microbiota is a source of sleep-promoting signals. Bacterial metabolites and components of the bacterial cell wall are likely to provide important links between the intestinal commensal flora and sleep-generating mechanisms in the brain. Butyrate is a short-chain fatty acid produced by the intestinal bacteria by the fermentation of nondigestible polysaccharides. We tested the hypothesis that butyrate may serve as a bacterial-derived sleep-promoting signal. Oral gavage administration of tributyrin, a butyrate pro-drug, elicited an almost 50% increase in non-rapid-eye movement sleep (NREMS) in mice for 4 hours after the treatment. Similarly, intraportal injection of butyrate led to prompt and robust increases in NREMS in rats. In the first 6 hours after the butyrate injection, NREMS increased by 70%. Both the oral and intraportal administration of butyrate led to a significant drop in body temperature. Systemic subcutaneous or intraperitoneal injection of butyrate did not have any significant effect on sleep or body temperature. The results suggest that the sleep-inducing effects of butyrate are mediated by a sensory mechanism located in the liver and/or in the portal vein wall. Hepatoportal butyrate-sensitive mechanisms may play a role in sleep modulation by the intestinal microbiota.
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Research Support, N.I.H., Extramural |
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Marts BC, Naunheim KS, Fiore AC, Pennington DG. Conservative versus surgical management of chylothorax. Am J Surg 1992; 164:532-4; discussion 534-5. [PMID: 1443383 DOI: 10.1016/s0002-9610(05)81195-x] [Citation(s) in RCA: 134] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Chylothorax is a potentially life-threatening disorder that has profound respiratory, nutritional, and immunologic consequences. Treatment for this problem is controversial, and the results have been variable. From 1985 to 1990, 29 patients (16 males, 13 females; mean age: 20.1 years; range: 5 days to 76.8 years) were diagnosed as having chylothorax (18 right, 6 left, 5 bilateral). Etiologies included surgical trauma (26) and nonsurgical trauma (3). Initial conservative treatment consisted of tube thoracostomy drainage (mean duration: 13.3 days; range: 1 to 62 days; mean total volume: 4,030 mL) and dietary modification (low-fat diet, total parenteral nutrition). This resulted in resolution of the chylothorax in 23 patients (79% success), although 2 patients died of unrelated causes while hospitalized (myocardial infarction and cardiopulmonary arrest). Five adult patients and one infant (21%) required ligation of the thoracic duct, with resolution of the chylothorax in all six (100% success). Despite successful duct closure, one infant died of respiratory failure unrelated to the operation, and one adult died as the result of a cerebrovascular accident 6 weeks postoperatively, yielding an operative mortality of 33% and an overall mortality of 14% (4 of 29). Our experience demonstrates that initial treatment of chylothorax with thoracostomy drainage and dietary modification is successful in the majority of patients and is not associated with high morbidity or mortality rates. Surgical intervention for chylothoraces that fail to respond to initial conservative measures will be required in a minority of patients but appears to be associated with a higher risk of complications.
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James LR, Tang D, Ingram A, Ly H, Thai K, Cai L, Scholey JW. Flux through the hexosamine pathway is a determinant of nuclear factor kappaB- dependent promoter activation. Diabetes 2002; 51:1146-56. [PMID: 11916938 DOI: 10.2337/diabetes.51.4.1146] [Citation(s) in RCA: 131] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The hexosamine pathway may mediate some of the toxic effects of glucose. We hypothesized that flux through this pathway might regulate the activity of nuclear factor kappaB (NF-kappaB)-dependent genes in mesangial cells (MCs). In MCs, RT-PCR revealed that high glucose (30 mmol/l) and glucosamine (1 mmol/l) increased mRNA levels for vascular cell adhesion molecule 1 (VCAM-1) and increased the activity of an NF-kappaB enhancer by 1.5- and 2-fold, respectively. Overexpression of glutamine:fructose-6-phosphate amidotransferase (GFAT), the rate-limiting enzyme for flux through the hexosamine pathway, led to a 2.2-fold increase in NF-kappaB enhancer activity; the combination of GFAT overexpression and high glucose increased activity 2.8-fold, and these increases were prevented by 40 micromol/l O-diazoacetyl-L-serine (azaserine) or 6-diazo-5-oxonorleucine. High glucose, glucosamine, and GFAT overexpression increased binding of MC nuclear proteins to NF-kappaB consensus sequences. Immunoblotting revealed that the p65 subunit of NF-kappaB was O-glycosylated in MC cultured in physiologic glucose and that significant enhancement occurred with high glucose and glucosamine. Both glucose and glucosamine dose-dependently increased human VCAM-1 promoter activity. In addition, GFAT overexpression activated the VCAM-1 promoter (2.25-fold), with further augmentation by high glucose and abrogation by inhibitors of GFAT, NF-kappaB, and O-glycosylation. Inactivation of the two NF-kappaB sites in the VCAM-1 promoter abolished its response to high glucose, glucosamine, and GFAT overexpression. These results suggest that increased flux through the hexosamine pathway leads to NF-kappaB-dependent promoter activation in MCs.
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Schwartz RH, Eaton J, Bower BD, Aynsley-Green A. Ketogenic diets in the treatment of epilepsy: short-term clinical effects. Dev Med Child Neurol 1989; 31:145-51. [PMID: 2786822 DOI: 10.1111/j.1469-8749.1989.tb03972.x] [Citation(s) in RCA: 125] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The classical 4:1 ketogenic diet, the medium-chain triglyceride (MCT) diet and a modified MCT diet were used in the treatment of 55 children and four adults with intractable epilepsy. During a three-month treatment period 51 of 63 studies (81 per cent) showed greater than 50 per cent reduction in seizure frequency. This improvement was independent of diet used and type of seizure experienced by patients. The diets were found to be acceptable and of therapeutic benefit to the children, but treatment of the four adult patients with the MCT diet was unsuccessful. There was no correlation between EEG changes and clinical response. The three ketogenic diets were shown to be effective in the short-term management of children whose epilepsy is poorly controlled with anticonvulsant drugs.
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Ip C, Scimeca JA, Thompson H. Effect of timing and duration of dietary conjugated linoleic acid on mammary cancer prevention. Nutr Cancer 1995; 24:241-7. [PMID: 8610043 DOI: 10.1080/01635589509514413] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Conjugated linoleic acid (CLA) is a minor fatty acid found predominantly in the form of triglycerides in beef and dairy products. Previous work by Ip and co-workers showed that free fatty acid-CLA at < or = 1% in the diet is protective against mammary carcinogenesis in rats. The present study verified that the anticancer activities of free fatty acid-CLA and triglyceride-CLA are essentially identical. This is an important finding, because it rules out a nonspecific free fatty acid effect. In terms of practical implication, we can continue the in vivo research with the less-expensive free fatty acid-CLA without compromising the physiological relevance of the data. A primary objective of this report was to investigate how the timing and duration of CLA feeding might affect the development of mammary carcinogenesis in the methylnitrosourea (MNU) model. We found that exposure to 1% CLA during the early postweaning and pubertal period only (from 21 to 42 days of age) was sufficient to reduce subsequent tumorigenesis induced by a single dose of MNU given at 56 days of age. This period incidentally corresponds to a time of active morphological development of the mammary gland to the mature state. In contrast to the above observation, a continuous intake of CLA was required for maximal inhibition of tumorigenesis when CLA feeding was started after MNU administration, suggesting that some active metabolite(s) of CLA might be involved in suppressing the process of neoplastic promotion/progression.
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Pires JAA, Souza AH, Grummer RR. Induction of Hyperlipidemia by Intravenous Infusion of Tallow Emulsion Causes Insulin Resistance in Holstein Cows. J Dairy Sci 2007; 90:2735-44. [PMID: 17517713 DOI: 10.3168/jds.2006-759] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The objective was to test whether the induction of elevated blood nonesterified fatty acids (NEFA) by i.v. infusion of a tallow emulsion altered glucose tolerance and responsiveness to insulin in Holstein cows. Six non-lactating, nongestating Holstein cows were assigned to a crossover design. One cow was excluded before initiation of the experiment because of complications from mastitis. Treatments consisted of 11-h i.v. infusions of saline (control) or a 20% (wt/vol) triacylglycerol (TG) emulsion derived from tallow (tallow) to elevate plasma NEFA. Each period consisted of two 11-h infusions (INF1 and INF2), separated by 1 d in which cows were not infused. Intravenous glucose tolerance tests (IVGTT) and insulin challenges (IC) were performed 8 h after initiation of INF1 and INF2, respectively. The infusion of treatments continued during the 3 h of sampling for IVGTT and IC. Cows were fed every 4 h at a rate to meet energy requirements for 5 d prior to each period, and every 2 h during the first 8 h of infusions. Infusion of tallow induced hyperlipidemia by increasing plasma NEFA (295 +/- 9 vs. 79 +/- 7 microEq/L), serum TG (41.0 +/- 6 vs. 11.4 +/- 4.4 mg/dL), and glycerol (0.81 +/- 0.09 vs. 0.23 +/- 0.1 mg/dL) concentrations during INF1. During INF2, tallow treatment increased plasma NEFA (347 vs. 139 +/- 18 microEq/L), serum TG (20.8 +/- 4.6 vs. 13.1 +/- 2.3 mg/dL), and glycerol (0.88 +/- 0.04 vs. 0.31 +/- 0.02 mg/dL) concentrations. Induction of hyperlipidemia impaired glucose clearance during IVGTT, despite the greater endogenous insulin response to the glucose infusion, leading to a lower insulin sensitivity index [0.29 vs. 1.88 +/- 0.31 x 10(-4) min(-1)/(microIU/mL)]. Accordingly, hyperlipidemia impaired glucose clearance during IC (1.58 vs. 2.72 %/min), reflecting lower responsiveness to insulin. These data show that induction of hyperlipidemia causes insulin resistance in Holstein cows by impairing both sensitivity and maximum responsiveness to insulin. The induction of insulin resistance by TG, NEFA, or both may increase the availability of glucogenic nutrients to the periparturient dairy cow. Yet excessive elevation of NEFA may potentially lead adipocytes to become more insulin resistant, further increasing plasma NEFA concentration and the risk of metabolic disorders.
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Jensen GL, Mascioli EA, Seidner DL, Istfan NW, Domnitch AM, Selleck K, Babayan VK, Blackburn GL, Bistrian BR. Parenteral infusion of long- and medium-chain triglycerides and reticuloendothelial system function in man. JPEN J Parenter Enteral Nutr 1990; 14:467-71. [PMID: 2122019 DOI: 10.1177/0148607190014005467] [Citation(s) in RCA: 116] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Previous study demonstrated that patients who received total parenteral nutrition (TPN) with standard intermittent infusion of long chain triglyceride (LCT) at 0.13 g kg-1hr-1 over 10 hr for each of three days showed a significant decline in 99Tc-sulfur colloid (TSC) clearance rate by the reticuloendothelial system (RES). The present studies evaluated eight patients who received the same total lipid dose of LCT infused continuously as in a three-in-one admixture, and another nine patients receiving the same amount of fat as a medium chain triglyceride (MCT)/LCT (75%/25%) emulsion intermittently over 10 hr at 0.13 g kg-1hr-1 for three consecutive days. Patients were given continuous total parenteral nutrition (TPN) comprised of protein, 1.5 g kg-1day-1, and dextrose, 4.5 g kg-1day-1. RES function was examined by measuring the clearance rates of intravenously injected TSC while receiving TPN containing only protein and dextrose, and again after three days of fat infusion. Mean (+/- SEM) clearance rate constants before and after continuous LCT infusion were 0.38 +/- 0.09 and 0.41 +/- 0.08 min-1, respectively, while those before and after intermittent MCT/LCT infusion were 0.50 +/- 0.18 and 0.73 +/- 0.24 min-1, respectively. In contrast to intermittent LCT infusion, the administration of continuous LCT or an intermittent MCT/LCT mixture does not impair TSC clearance by the RES. These findings suggest that condensing the daily period of LCT infusion at standard dosage may exceed the rate of metabolic utilization, resulting in increased fat removal and diminished TSC uptake by the RES.(ABSTRACT TRUNCATED AT 250 WORDS)
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Taguchi H, Nagao T, Watanabe H, Onizawa K, Matsuo N, Tokimitsu I, Itakura H. Energy value and digestibility of dietary oil containing mainly 1,3-diacylglycerol are similar to those of triacylglycerol. Lipids 2001; 36:379-82. [PMID: 11383689 DOI: 10.1007/s11745-001-0731-7] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Diacylglycerol (DAG) is a component of various vegetable oils. Approximately 70% of the DAG in edible oils are in the configuration of 1,3-DAG. We recently showed that long-term ingestion of dietary oil containing mainly 1,3-DAG reduces body fat accumulation in humans as compared to triacylglycerol (TAG) oil with a similar fatty acid composition. As the first step to elucidate the mechanism for this result, we examined the difference in the bioavailabilities of both oils by measuring food energy values and digestibilities in rats. Energy values of the DAG oil and the TAG oil, measured by bomb calorimeter, were 38.9 and 39.6 kJ/g, respectively. Apparent digestibility expressed according to the formula: (absorbed) x (ingested)(-1) x 100 = (ingested - excreted in feces) x (ingested)(-1) x 100 for the DAG oil and the TAG oil were 96.3+/-0.4 and 96.3+/-0.3% (mean +/- SEM), respectively. The similarity in the bioavailabilities of both oils supports the hypothesis that the reduced fat accumulation by dietary DAG is caused by the different metabolic fates after the absorption into the gastrointestinal epithelial cells.
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Comparative Study |
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Feinle-Bisset C, Patterson M, Ghatei MA, Bloom SR, Horowitz M. Fat digestion is required for suppression of ghrelin and stimulation of peptide YY and pancreatic polypeptide secretion by intraduodenal lipid. Am J Physiol Endocrinol Metab 2005; 289:E948-E953. [PMID: 15998659 DOI: 10.1152/ajpendo.00220.2005] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Stimulation of cholecystokinin and glucagon-like peptide-1 secretion by fat is mediated by the products of fat digestion. Ghrelin, peptide YY (PYY), and pancreatic polypeptide (PP) appear to play an important role in appetite regulation, and their release is modulated by food ingestion, including fat. It is unknown whether fat digestion is a prerequisite for their suppression (ghrelin) or release (PYY, PP). Moreover, it is not known whether small intestinal exposure to fat is sufficient to suppress ghrelin secretion. Our study aimed to resolve these issues. Sixteen healthy young males received, on two separate occasions, 120-min intraduodenal infusions of a long-chain triglyceride emulsion (2.8 kcal/min) 1) without (condition FAT) or 2) with (FAT-THL) 120 mg of tetrahydrolipstatin (THL, lipase inhibitor), followed by a standard buffet-style meal. Blood samples for ghrelin, PYY, and PP were taken throughout. FAT infusion was associated with a marked, and progressive, suppression of plasma ghrelin from t = 60 min (P < 0.001) and stimulation of PYY from t = 30 min (P < 0.01). FAT infusion also stimulated plasma PP (P < or = 0.01), and the release was immediate. FAT-THL completely abolished the FAT-induced changes in ghrelin, PYY, and PP. In response to the meal, plasma ghrelin was further suppressed, and PYY and PP stimulated, during both FAT and FAT-THL infusions. In conclusion, in healthy humans, 1) the presence of fat in the small intestine suppresses ghrelin secretion, and 2) fat-induced suppression of ghrelin and stimulation of PYY and PP is dependent on fat digestion.
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Randomized Controlled Trial |
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Egorin MJ, Yuan ZM, Sentz DL, Plaisance K, Eiseman JL. Plasma pharmacokinetics of butyrate after intravenous administration of sodium butyrate or oral administration of tributyrin or sodium butyrate to mice and rats. Cancer Chemother Pharmacol 1999; 43:445-53. [PMID: 10321503 DOI: 10.1007/s002800050922] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE To define the plasma concentrations of butyrate achieved and the profile of plasma butyrate concentrations versus time in mice and rats treated with tributyrin or sodium butyrate. METHODS Female CD2F1 mice were treated with tributyrin by oral gavage or with sodium butyrate by i.v. bolus or oral gavage. Oral tributyrin doses delivered to mice were 3.1, 5.2, 7.8, and 10.3 g/kg. Intravenous sodium butyrate doses were 0.31, 0.62, 0.94, and 1.25 g/kg. Oral sodium butyrate was given to mice at 5 g/kg. Subsequently, similar studies were performed in female Sprague-Dawley rats. Rats were given tributyrin by oral gavage at doses of 3.6, 5.2, or 10.3 g/kg or sodium butyrate i.v. at a dose of 500 mg/kg. Plasma butyrate concentrations were determined by gas chromatography. RESULTS In mice, oral dosing with tributyrin resulted in detectable plasma butyrate concentrations as early as at 5 min after treatment and produced peak plasma butyrate concentrations at between 15 and 60 min after dosing. Peak plasma butyrate concentrations increased proportionally with increasing tributyrin dose, but as the oral tributyrin dose increased there was a greater than proportional increase in the area under the curve of plasma butyrate concentrations versus time (AUC). At a tributyrin dose of 10.3 g/kg, plasma butyrate concentrations peaked at approximately 1.75 mM and remained >1 mM for between 10 and 60 min after dosing. However, approximately 10% of mice treated with this dose died acutely. At a tributyrin dose of 7.8 g/kg, plasma butyrate concentrations reached approximately 1 mM by 15 min after dosing and remained between 0.8 and 1 mM until 60 min after dosing. No mouse treated with this dose died acutely. Mice given tributyrin doses of 5.2 and 3.1 g/kg achieved peak plasma butyrate concentrations of approximately 0.9 and 0.5 mM, respectively, by 45 min after dosing. Plasma butyrate concentrations in these mice remained above 0.1 mM until 120 and 90 min after dosing, respectively. The four i.v. doses of sodium butyrate resulted in plasma concentration-time profiles that also indicated nonlinear pharmacokinetics and were well described by a one-compartment model with saturable elimination. Values recorded for the Michaelis-Menten constant (Km) and the maximal velocity of the process (Vmax) ranged between 1.02 and 5.65 mM and 0.60 and 1.82 mmol/min, respectively. Values noted for the volume of the central compartment (Vc) varied between 0.48 and 0.72 l/kg. At 1.25 g/kg, i.v. sodium butyrate produced peak plasma butyrate concentrations of 10.5-17.7 mM, and plasma butyrate concentrations remained above 1 mM for 20-30 min. Sodium butyrate delivered orally to mice at 5 g/kg produced peak plasma butyrate concentrations of approximately 9 mM at 15 min after dosing and plasma butyrate concentrations exceeding 1 mM for 90 min after dosing. In rats the 10.3-g/kg oral dose of tributyrin produced peak plasma butyrate concentrations of approximately 3 mM by 75 min after dosing and butyrate concentrations exceeding 1 mM from 30 to 90 min after dosing. The plasma butyrate concentrations produced in rats by 5.2- and 3.6-g/kg doses were appropriately lower than those produced by the 10.3-g/kg dose, and there was no evidence of nonlinearity. The 500-mg/kg i.v. dose of sodium butyrate produced peak plasma butyrate concentrations in rats of approximately 11 mM, and the decline in plasma butyrate concentrations with time after dosing was consistent with saturable clearance. CONCLUSION These studies document the ability to use oral administration of tributyrin to achieve pharmacologically relevant concentrations of butyrate in rodent plasma. They also document the nonlinear nature of butyrate clearance. These data are being used in the design of clinical trials of oral tributyrin in patients with malignancies and hemoglobinopathies.
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