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Talal S, Chahal A, Osgood GM, Brosemann J, Harrison JF, Cease AJ. Target for lipid-to-carbohydrate intake minimizes cost of growth. Proc Biol Sci 2024; 291:20240424. [PMID: 38807520 DOI: 10.1098/rspb.2024.0424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 04/04/2024] [Indexed: 05/30/2024] Open
Abstract
Many theoretical treatments of foraging use energy as currency, with carbohydrates and lipids considered interchangeable as energy sources. However, herbivores must often synthesize lipids from carbohydrates since they are in short supply in plants, theoretically increasing the cost of growth. We tested whether a generalist insect herbivore (Locusta migratoria) can improve its growth efficiency by consuming lipids, and whether these locusts have a preferred caloric intake ratio of carbohydrate to lipid (C : L). Locusts fed pairs of isocaloric, isoprotein diets differing in C and L consistently selected a 2C : 1L target. Locusts reared on isocaloric, isoprotein 3C : 0L diets attained similar final body masses and lipid contents to locusts fed the 2C : 1L diet, but they ate more and had a ~12% higher metabolic rate, indicating an energetic cost for lipogenesis. These results demonstrate that some animals can selectively regulate carbohydrate-to-lipid intake and that consumption of dietary lipids can improve growth efficiency.
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Affiliation(s)
- Stav Talal
- School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
| | | | - Geoffrey M Osgood
- School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
| | - Jonah Brosemann
- School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
| | - Jon F Harrison
- School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
| | - Arianne J Cease
- School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
- School of Sustainability, Arizona State University, Tempe, AZ 85281, USA
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Zeng FF, Chen ZY, Zheng JS, Lin JS, Li YH, Qiu R, Wang C, Sun LL, Chen YM. Association between erythrocyte fatty acids in de novo lipogenesis pathway and DXA-derived body fat and trunk fat distribution in Chinese adults: a prospective study. Eur J Nutr 2018; 58:3229-3239. [PMID: 30470880 DOI: 10.1007/s00394-018-1866-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 11/19/2018] [Indexed: 11/29/2022]
Abstract
PURPOSE Higher levels of fatty acids (FAs) in the de novo lipogenesis (DNL) pathway might be associated with higher levels of fat mass (FM), while limited evidence is available from the general population. We aimed to examine the associations between DNL-FAs and body fat and fat distribution in a general population of Chinese adults. METHODS This community-based prospective cohort study included 3,075 participants (68% women) aged 40-75 years in urban Guangzhou, China. We measured erythrocyte DNL-FAs composition (including C16:0, C16:1n-7, C18:0, and C18:1n-9) at baseline and %FM over the total body (TB), trunk, limbs, android (A) and gynoid (G) regions after 3.2 years and 6.3 years of follow-up, respectively. RESULTS Generally, higher proportions of individual erythrocyte DNL-FAs and their combined index were positively associated with adipose indices in the multivariable cross-sectional and longitudinal analyses. The cross-sectional percentage mean differences in quartile 4 (vs. 1) of the DNL index were 3.43% (TB), 4.56% (trunk), and 2.67% (A/G ratio) (all P trends < 0.01). The corresponding values in longitudinal changes of adipose indices were 1.40% (TB), 1.78% (trunk), and 1.32% (A) (all P trends < 0.05). The above associations tended to be more pronounced in the trunk and android area than the limbs and gynoid area. CONCLUSIONS Erythrocyte DNL-FAs may contribute to an increase in total body fat in Chinese adults, particularly FM distributed in trunk and abdominal regions.
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Affiliation(s)
- Fang-Fang Zeng
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China.,Department of Epidemiology, School of Basic Medical Sciences, Jinan University, No. 601 Huangpu Road West, Guangzhou, 510632, Guangdong, People's Republic of China
| | - Zhan-Yong Chen
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China
| | - Ju-Sheng Zheng
- MRC Epidemiology Unit, University of Cambridge, Cambridge, CB20QQ, UK
| | - Jie-Sheng Lin
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China
| | - Yi-Hong Li
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China
| | - Rui Qiu
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China
| | - Cheng Wang
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China
| | - Li-Li Sun
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China
| | - Yu-Ming Chen
- Guangdong Provincial Key Laboratory of Food, Nutrition and Health, School of Public Health, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China. .,Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, 510080, People's Republic of China.
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Kagya-Agyemang JK, Vaanholt LM, Hambly C, Król E, Mitchell SE, Speakman JR. Limits to sustained energy intake XXVIII: Beneficial effects of high dietary fat on lactation performance in mice. J Exp Biol 2018; 221:jeb.180828. [DOI: 10.1242/jeb.180828] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/20/2018] [Indexed: 12/22/2022]
Abstract
Maximal animal performance may be limited by the ability of animals to dissipate heat; the heat dissipation limitation (HDL) theory. Since diets vary in the incidental heat produced during digestion (specific dynamic action, SDA), the HDL theory predicts lactating female mice consuming diets with lower SDA should have increased reproductive performance. Dietary fat has a lower SDA than dietary carbohydrate. Female mice were fed low (LF), medium (MF) or high fat (HF) diets (10%, 45% and 60% energy from fat respectively) from days 4-18 of lactation. HF and MF-fed mice weaned significantly heavier litters than LF mice. This was because they not only consumed more energy (metabolisable energy intake, Emei; HF:306.5±25.0, MF:340.5±13.5 kJ d−1) at peak lactation, but also delivered more milk energy to their pups (milk energy output, Emilk: 203.2±49.9, 229.3±42.2 kJ d−1 respectively) than the LF-fed mice (Emei =266.7±4.5, Emilk =164.60±30.59 kJ d−1). This effect was greater than predicted from the SDA of the different diets combined with a mathematical model based on the HDL theory. Fatty acid profiles of the diets, milk and pups, showed significant correlations between the profiles. Besides reduced SDA, HF and MF-fed mice were probably able to directly transfer absorbed dietary fat into milk, reducing the heat production of lactogenesis, and enabling them to perform better than expected from the HDL model. In summary, HF and MF diets had beneficial effects on reproductive performance compared to the LF diet because they enabled mice to generate milk more efficiently with less incidental heat production.
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Affiliation(s)
- J. K. Kagya-Agyemang
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, UK
- College of Agriculture Education, University of Education, Winneba, P.O. Box 40, Mampong-Ashanti, Ghana
| | - L. M. Vaanholt
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, UK
| | - C. Hambly
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, UK
| | - E. Król
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, UK
| | - S. E. Mitchell
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, UK
| | - J. R. Speakman
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, UK
- State key laboratory of molecular developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing China
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Guidotti S, Meijer HAJ, van Dijk G. Validity of the doubly labeled water method for estimating CO2 production in mice under different nutritional conditions. Am J Physiol Endocrinol Metab 2013; 305:E317-24. [PMID: 23715730 DOI: 10.1152/ajpendo.00192.2013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The doubly labeled water (DLW) technique is used to assess metabolic rate (MR) in free-living conditions. We investigated whether differences in the nutritional and body adiposity status affect validity of the assessment of CO2 production (rCO2) by the DLW technique. To serve this purpose, we compared calculated rCO2 by the DLW method to actual CO2 production concomitantly measured in an indirect calorimetry setup over a 3-day period in mice fed with a low-fat (LF) diet or an obesogenic high-fat/high-sucrose (HF) diet. To uncover a potential effect of body composition on DLW accuracy, the HF-fed group was further subdivided in a diet-induced obesity-prone (DIO) and diet-induced obesity-resistant (DR) group. Furthermore, we assessed the influence of different sampling protocols, duration, and methodology of calculation. An excellent match was found between rCO2 assessed by the two methods in the LF-fed mice (least discrepancy -0.5 ± 1.1%). In contrast, there was a consistent overestimation of rCO2 by the DLW technique in the HF-fed animals compared with actual CO2 production independent from body mass gain (least discrepancy DR +15.9 ± 2.2%, DIO +18.5 ± 3.2%). The least discrepancies were found when two-pool model equations and the intercept method were used to calculate the body water pool. Furthermore, the HF group presented different equilibration kinetics of (2)H and (18)O and a lower dilution space ratio between the two. We recommend particular caution when using the DLW method for MR assessment in HF-fed animals and potentially humans because of the overestimation of rCO2.
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Affiliation(s)
- Stefano Guidotti
- Center for Isotope Research, Energy and Sustainability Research Institute Groningen, University of Groningen, Groningen, The Netherlands
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Wu JHY, Lemaitre RN, Imamura F, King IB, Song X, Spiegelman D, Siscovick DS, Mozaffarian D. Fatty acids in the de novo lipogenesis pathway and risk of coronary heart disease: the Cardiovascular Health Study. Am J Clin Nutr 2011; 94:431-8. [PMID: 21697077 PMCID: PMC3142722 DOI: 10.3945/ajcn.111.012054] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND De novo lipogenesis (DNL) is an endogenous pathway whereby carbohydrates and proteins are converted to fatty acids. DNL could affect coronary heart disease (CHD) or sudden cardiac arrest (SCA) via generation of specific fatty acids. Whether these fatty acids are prospectively associated with SCA or other CHD events is unknown. OBJECTIVE The objective was to investigate the relations of 4 fatty acids in the DNL pathway-palmitic acid (16:0), palmitoleic acid (16:1n-7), 7-hexadecenoic acid (16:1n-9), and cis-vaccenic acid (18:1n-7)-with incident CHD, including fatal CHD, nonfatal myocardial infarction (NFMI), and SCA. DESIGN A community-based prospective study was conducted in 2890 men and women aged ≥65 y, who were free of known CHD at baseline and who were followed from 1992 to 2006. Cardiovascular disease risk factors and plasma phospholipid fatty acids were measured at baseline by using standardized methods. Incident CHD was ascertained prospectively and was centrally adjudicated by using medical records. Risk was assessed by using multivariable-adjusted Cox proportional hazards. RESULTS During 29,835 person-years of follow-up, 631 CHD and 71 SCA events occurred. Both 18:1n-7 and 16:1n-9 were associated with a higher risk of SCA [multivariable-adjusted hazard ratio (95% CI) for the interquintile range: 7.63 (2.58, 22.6) for 18:1n-7 and 2.30 (1.16, 4.55) for 16:1n-9] but not of total CHD, fatal CHD, or NFMI. In secondary analyses censored to mid-follow-up (7 y) to minimize the effects of changes in concentrations over time, 16:1n-9 was also associated with a significantly higher risk of total CHD (2.11; 1.76, 2.54), including a higher risk of CHD death, NFMI, and SCA; 16:0 and 16:1n-7 were not associated with clinical CHD outcomes. CONCLUSION Higher plasma phospholipid 18:1n-7 and 16:1n-9 concentrations were prospectively associated with an elevated risk of SCA but not of other CHD events, except in secondary analyses.
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Affiliation(s)
- Jason H Y Wu
- Division of Cardiovascular Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
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Vogt JA, Ishii-Schrade KB, Pencharz PB, Jones PJH, Wolever TMS. L-rhamnose and lactulose decrease serum triacylglycerols and their rates of synthesis, but do not affect serum cholesterol concentrations in men. J Nutr 2006; 136:2160-6. [PMID: 16857835 DOI: 10.1093/jn/136.8.2160] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Colonic short-chain fatty acids (SCFA) may affect hepatic lipid metabolism. Lactulose increases colonic acetate production, whereas L-rhamnose increases propionate. To test the effects of oral L-rhamnose and lactulose for 28 d on fasting concentrations and hepatic synthesis of lipids in humans, 18 men were administered 25 g/d of L-rhamnose, lactulose, or d-glucose for 4 wk in a partially randomized crossover design, with blood collected from fasting subjects on the first and last day of each period. Cholesterol and triacylglycerol (TG) synthesis rates were determined using deuterated water uptake rate over the last 24 h of each period. Postprandial blood lipids, and glucose and insulin were assessed in 11 subjects on d 28. Fasting serum cholesterol was unchanged; however, when expressed as a percentage change, TG were decreased, relative to baseline (P < 0.04), by L-rhamnose (-10%) and lactulose (-10%), compared with D-glucose, which increased serum TG (+11%). Net TG-fatty acid (TGFA) synthesis on d 28 was lower with L-rhamnose (2.42 +/- 0.38 g/d) and lactulose (2.62 +/- 0.35 g/d) than with D-glucose (2.96 +/- 0.31 g/d, P < 0.01). We conclude that these results do not support a primary role for propionate in the cholesterol-lowering effect of soluble fiber. However, both lactulose and L-rhamnose lowered serum TG (expressed as a percentage change) and TGFA synthesis, compared with d-glucose, which increased them. Although these data are consistent with inhibition of TGFA synthesis by SCFA, other aspects of the metabolism of these sugars cannot be ruled out as putative agents of their TG-lowering effects.
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Affiliation(s)
- Janet A Vogt
- Clinical Nutrition and Risk Factor Modification Centre, St. Michael's Hospital, Toronto, ON, Canada
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Dolnikowski GG, Marsh JB, Das SK, Welty FK. Stable isotopes in obesity research. MASS SPECTROMETRY REVIEWS 2005; 24:311-327. [PMID: 15389849 DOI: 10.1002/mas.20021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Obesity is recognized as a major public health problem. Obesity is a multifactorial disease and is often associated with a wide range of comorbidities including hypertension, non-insulin dependent (Type II) diabetes mellitus, and cardiovascular disease, all of which contribute to morbidity and mortality. This review deals with stable isotope mass spectrometric methods and the application of stable isotopes to metabolic studies of obesity. Body composition and total energy expenditure (TEE) can be measured by mass spectrometry using stable isotope labeled water, and the metabolism of protein, lipid, and carbohydrate can be measured using appropriate labeled tracer molecules.
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Affiliation(s)
- Gregory G Dolnikowski
- Jean Mayer USDA Human Nutrition Center on Aging at Tufts University, 711 Washington Street, Boston, Massachusetts 02111, USA.
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Elliott SS, Keim NL, Stern JS, Teff K, Havel PJ. Fructose, weight gain, and the insulin resistance syndrome. Am J Clin Nutr 2002; 76:911-22. [PMID: 12399260 DOI: 10.1093/ajcn/76.5.911] [Citation(s) in RCA: 646] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
This review explores whether fructose consumption might be a contributing factor to the development of obesity and the accompanying metabolic abnormalities observed in the insulin resistance syndrome. The per capita disappearance data for fructose from the combined consumption of sucrose and high-fructose corn syrup have increased by 26%, from 64 g/d in 1970 to 81 g/d in 1997. Both plasma insulin and leptin act in the central nervous system in the long-term regulation of energy homeostasis. Because fructose does not stimulate insulin secretion from pancreatic beta cells, the consumption of foods and beverages containing fructose produces smaller postprandial insulin excursions than does consumption of glucose-containing carbohydrate. Because leptin production is regulated by insulin responses to meals, fructose consumption also reduces circulating leptin concentrations. The combined effects of lowered circulating leptin and insulin in individuals who consume diets that are high in dietary fructose could therefore increase the likelihood of weight gain and its associated metabolic sequelae. In addition, fructose, compared with glucose, is preferentially metabolized to lipid in the liver. Fructose consumption induces insulin resistance, impaired glucose tolerance, hyperinsulinemia, hypertriacylglycerolemia, and hypertension in animal models. The data in humans are less clear. Although there are existing data on the metabolic and endocrine effects of dietary fructose that suggest that increased consumption of fructose may be detrimental in terms of body weight and adiposity and the metabolic indexes associated with the insulin resistance syndrome, much more research is needed to fully understand the metabolic effect of dietary fructose in humans.
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Affiliation(s)
- Sharon S Elliott
- Department of Nutrition, University of California, Davis 95616, USA
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McDevitt RM, Bott SJ, Harding M, Coward WA, Bluck LJ, Prentice AM. De novo lipogenesis during controlled overfeeding with sucrose or glucose in lean and obese women. Am J Clin Nutr 2001; 74:737-46. [PMID: 11722954 DOI: 10.1093/ajcn/74.6.737] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND The results of previous studies suggest that de novo lipogenesis may play an important role in the etiology of obesity, particularly during overconsumption of different carbohydrates. OBJECTIVE We hypothesized that de novo lipogenesis would increase during overfeeding, would vary depending on the type of carbohydrate consumed, and would be greater in obese than in lean women. DESIGN De novo lipogenesis was measured during 96 h of overfeeding by 50% with either sucrose or glucose and during an energy balance treatment (control) in 8 lean and 5 obese women. De novo lipogenesis was determined by measuring the amount of deuterium incorporation into plasma triacylglycerols. Fat and carbohydrate balance were measured simultaneously by continuous whole-body calorimetry. RESULTS De novo lipogenesis did not differ significantly between lean and obese subjects, except with the control treatment, for which de novo lipogenesis was greater in the obese subjects. De novo lipogenesis was 2- to 3-fold higher after overfeeding by 50% than after the control treatment in all subjects. The type of carbohydrate overfeeding (sucrose or glucose) had no significant effect on de novo lipogenesis in either subject group. Estimated amounts of absolute VLDL production ranged from a minimum of 2 g/d (control) to a maximum of 10 g/d after overfeeding. This compares with a mean fat balance of approximately 275 g after 96 h of overfeeding. Individual subjects showed characteristic amounts of de novo lipogenesis, suggesting constitutive (possibly genetic) differences. CONCLUSION De novo lipogenesis increases after overfeeding with glucose and sucrose to the same extent in lean and obese women but does not contribute greatly to total fat balance.
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Affiliation(s)
- R M McDevitt
- Department of Biochemistry and Nutrition, Scottish Agricultural College, Ayr, United Kingdom.
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Abstract
Humans can maintain health on diets differing widely in their macronutrient content, and numerous diet recommendations have been made to maintain health and to help weight control. Net adenosine triphosphate yields during the oxidation of carbohydrate, fat, and protein come to 75%, 90%, and 55%, respectively. However, macronutrient proportions can only be varied within limits, and differences in energy dissipation achievable by macronutrient exchanges are minor. In the National Health and Nutrition Examination Survey III data, stature explains 10% to 16% of the variance in fat-free mass in adults (the most significant predictor of resting energy expenditure), but <1% of the variance in the percentage of body fat. Thus, differences in resting energy expenditure cannot be expected to have much effect on adiposity. Recommendations designed to facilitate weight control, therefore, should be based on their potential impact on food consumption and energy intake. They should also reflect the fact that the logic for nutrient selection is not the same during weight maintenance and weight reduction. Glycogen levels, along with inherited traits and exercise habits, influence fat oxidation, and, hence, the size that the adipose tissue mass has to reach for fat oxidation to become commensurate with fat intake. Recent increases in the prevalence of obesity could have been brought about by the effect of changes in the food supply and by further declines in physical activity on habitual glycogen levels. Given that biological evolution led to food intake regulating mechanisms that are more powerful in promoting search for food than in seeking to restrain energy intake, it is not surprising that constant availability of desirable foods would lead to a high prevalence of obesity.
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Affiliation(s)
- J P Flatt
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical chool, Worcester, 01655, USA.
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Guo ZK, Cella LK, Baum C, Ravussin E, Schoeller DA. De novo lipogenesis in adipose tissue of lean and obese women: application of deuterated water and isotope ratio mass spectrometry. Int J Obes (Lond) 2000; 24:932-7. [PMID: 10918543 DOI: 10.1038/sj.ijo.0801256] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To evaluate the feasibility of using deuterated water and isotope ratio mass spectrometry to measure de novo fatty acid synthesis in adipose tissue, and to compare this parameter in obese and lean women. SUBJECTS Six lean and six obese premenopausal Caucasian women in the main study and three obese Pima Indians in a pilot study. MEASUREMENTS Deuterated water was administered orally twice daily for 14 days to create stable deuterium enrichment in body water, during which series of blood samples were collected to measure body water deuterium enrichment and deuterium incorporation into plasma total Triacylglycerol (TG) fatty acids and total cholesterol. Subcutaneous fat at different sites were sampled at the beginning and the end of deuterium administration to measure deuterium incorporation into TG fatty acids. RESULTS Fractional de novo synthesis rate of TG fatty acids in adipose tissue was 0. 014+/-0.005 and 0.014+/-0.007% in lean and obese Caucasian women, corresponding to 2+/-0.7 and 5.6+/-3.2 g (P=0.3) of fatty acids synthesized daily, respectively. Plasma TG fatty acids and cholesterol synthesis rates were comparable to those reported previously. A pilot study showed that de novo lipid synthesis in adipose tissue of obese Pima Indians was also quantitatively minor. CONCLUSION Human adipose tissue, like the liver, does not make a major contribution to whole body lipogenesis under eucaloric conditions. A combination of deuterated water and isotope ratio mass spectrometry is a useful research tool for studying accumulation of de novo synthesized lipids in human adipose tissue.
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Affiliation(s)
- Z K Guo
- Department of Medicine, University of Chicago, Chicago, IL 60637, USA
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Park J, Lemieux S, Lewis GF, Kuksis A, Steiner G. Chronic exogenous insulin and chronic carbohydrate supplementation increase de novo VLDL triglyceride fatty acid production in rats. J Lipid Res 1997. [DOI: 10.1016/s0022-2275(20)30037-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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