Abstract
Obesity is the common expression of several diverse interacting genetic, familial and environmental factors. In addition to having hypertrophic fat cells because of inordinate triglyceride accumulation, many patients with childhood-onset obesity and those who are massively obese regardless of age at onset have an excessive number of adipocytes. Several endocrinologic and metabolic abnormalities are associated with obesity. Triglyceride formation in and lipid mobilization from hypertrophic adipocytes are exaggerated. The increased availability of free fatty acids to the liver contributes to the excessive synthesis of triglycerides and very-low-density lipoproteins; thus, hypertriglyceridemia is frequently associated with obesity. Hepatic synthesis and biliary excretion of cholesterol are also increased. Most of the excess cholesterol is stored in fat cells. The plasma concentrations of high-density lipoproteins are decreased. Hyperinsulinemia, which is characteristically found in the obese, leads to a decreased number of insulin receptors in target cells. The relative insulin insensitivity of the obese frequently results in glucose intolerance. The endocrinologic and metabolic abnormalities are correctable by an appropriate program of meal planning and physical activity.
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- Bagdade J. D., Porte D., Jr, Brunzell J. D., Bierman E. L. Basal and stimulated hyperinsulinism: reversible metabolic sequelae of obesity. J Lab Clin Med. 1974 Apr;83(4):563–569. [PubMed] [Google Scholar]
- Bar R. S., Gorden P., Roth J., Kahn C. R., De Meyts P. Fluctuations in the affinity and concentration of insulin receptors on circulating monocytes of obese patients: effects of starvation, refeeding, and dieting. J Clin Invest. 1976 Nov;58(5):1123–1135. doi: 10.1172/JCI108565. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bennion L. J., Grundy S. M. Effects of obesity and caloric intake on biliary lipid metabolism in man. J Clin Invest. 1975 Oct;56(4):996–1011. doi: 10.1172/JCI108180. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bierman E. L., Stein O., Stein Y. Lipoprotein uptake and metabolism by rat aortic smooth muscle cells in tissue culture. Circ Res. 1974 Jul;35(1):136–150. doi: 10.1161/01.res.35.1.136. [DOI] [PubMed] [Google Scholar]
- Bilheimer D. W., Eisenberg S., Levy R. I. The metabolism of very low density lipoprotein proteins. I. Preliminary in vitro and in vivo observations. Biochim Biophys Acta. 1972 Feb 21;260(2):212–221. doi: 10.1016/0005-2760(72)90034-3. [DOI] [PubMed] [Google Scholar]
- Björntorp P., Sjöström L. The composition and metabolism in vitro of adipose tissue fat cells of different sizes. Eur J Clin Invest. 1972 Jan;2(2):78–84. doi: 10.1111/j.1365-2362.1972.tb00573.x. [DOI] [PubMed] [Google Scholar]
- Bortz W. M., Paul P., Haff A. C., Holmes W. L. Glycerol turnover and oxidation in man. J Clin Invest. 1972 Jun;51(6):1537–1546. doi: 10.1172/JCI106950. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Brown M. S., Goldstein J. L. Receptor-mediated control of cholesterol metabolism. Science. 1976 Jan 16;191(4223):150–154. doi: 10.1126/science.174194. [DOI] [PubMed] [Google Scholar]
- Coluzzi M., Bullini L. Enzyme variants as markers in the study of pre-copulatory isolating mechanisms. Nature. 1971 Jun 18;231(5303):455–456. doi: 10.1038/231455a0. [DOI] [PubMed] [Google Scholar]
- D'Costa M. A., Angel A. Inhibition of hormone-stimulated lipolysis by clofibrate. A possible mechanism for its hypolipidemic action. J Clin Invest. 1975 Jan;55(1):138–148. doi: 10.1172/JCI107904. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Farkas J., Angel A., Avigan M. I. Studies on the compartmentation of lipid in adipose cells. II. Cholesterol accumulation and distribution in adipose tissue components. J Lipid Res. 1973 May;14(3):344–356. [PubMed] [Google Scholar]
- Felig P., Wahren J., Hendler R., Brundin T. Splanchnic glucose and amino acid metabolism in obesity. J Clin Invest. 1974 Feb;53(2):582–590. doi: 10.1172/JCI107593. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gordon T., Castelli W. P., Hjortland M. C., Kannel W. B., Dawber T. R. High density lipoprotein as a protective factor against coronary heart disease. The Framingham Study. Am J Med. 1977 May;62(5):707–714. doi: 10.1016/0002-9343(77)90874-9. [DOI] [PubMed] [Google Scholar]
- Grey N., Kipnis D. M. Effect of diet composition on the hyperinsulinemia of obesity. N Engl J Med. 1971 Oct 7;285(15):827–831. doi: 10.1056/NEJM197110072851504. [DOI] [PubMed] [Google Scholar]
- Harrison L. C., Martin F. I., Melick R. A. Correlation between insulin receptor binding in isolated fat cells and insulin sensitivity in obese human subjects. J Clin Invest. 1976 Dec;58(6):1435–1441. doi: 10.1172/JCI108599. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Heimberg M., Wilcox H. G. The effect of palmitic and oleic acids on the properties and composition of the very low density lipoprotein secreted by the liver. J Biol Chem. 1972 Feb 10;247(3):875–880. [PubMed] [Google Scholar]
- Knittle J. L., Ginsberg-Fellner F. Effect of weight reduction on in vitro adipose tissue lipolysis and cellularity in obese adolescents and adults. Diabetes. 1972 Jun;21(6):754–761. doi: 10.2337/diab.21.6.754. [DOI] [PubMed] [Google Scholar]
- Miettinen T. A. Cholesterol production in obesity. Circulation. 1971 Nov;44(5):842–850. doi: 10.1161/01.cir.44.5.842. [DOI] [PubMed] [Google Scholar]
- Miller G. J., Miller N. E. Plasma-high-density-lipoprotein concentration and development of ischaemic heart-disease. Lancet. 1975 Jan 4;1(7897):16–19. doi: 10.1016/s0140-6736(75)92376-4. [DOI] [PubMed] [Google Scholar]
- Nestel P. J., Whyte H. M., Goodman D. S. Distribution and turnover of cholesterol in humans. J Clin Invest. 1969 Jun;48(6):982–991. doi: 10.1172/JCI106079. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nestel P. J., Whyte H. M. Plasma free fatty acid and triglyceride turnover in obesity. Metabolism. 1968 Dec;17(12):1122–1128. doi: 10.1016/0026-0495(68)90092-9. [DOI] [PubMed] [Google Scholar]
- Nestel P., Goldrick B. Obesity: changes in lipid metabolism and the role of insulin. Clin Endocrinol Metab. 1976 Jul;5(2):313–335. doi: 10.1016/s0300-595x(76)80024-2. [DOI] [PubMed] [Google Scholar]
- Olefsky J. M., Farquhar J. W., Reaven G. M. Reappraisal of the role of insulin in hypertriglyceridemia. Am J Med. 1974 Oct;57(4):551–560. doi: 10.1016/0002-9343(74)90006-0. [DOI] [PubMed] [Google Scholar]
- Posner B. I. Polypeptide hormone receptors: characteristics and applications. Can J Physiol Pharmacol. 1975 Oct;53(5):689–703. doi: 10.1139/y75-097. [DOI] [PubMed] [Google Scholar]
- Poznanski W. J., Waheed I., Van R. Human fat cell precursors. Morphologic and metabolic differentiation in culture. Lab Invest. 1973 Nov;29(5):570–576. [PubMed] [Google Scholar]
- RABINOWITZ D., ZIERLER K. L. Forearm metabolism in obesity and its response to intra-arterial insulin. Characterization of insulin resistance and evidence for adaptive hyperinsulinism. J Clin Invest. 1962 Dec;41:2173–2181. doi: 10.1172/JCI104676. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rhoads G. G., Gulbrandsen C. L., Kagan A. Serum lipoproteins and coronary heart disease in a population study of Hawaii Japanese men. N Engl J Med. 1976 Feb 5;294(6):293–298. doi: 10.1056/NEJM197602052940601. [DOI] [PubMed] [Google Scholar]
- Salans L. B., Cushman S. W., Weismann R. E. Studies of human adipose tissue. Adipose cell size and number in nonobese and obese patients. J Clin Invest. 1973 Apr;52(4):929–941. doi: 10.1172/JCI107258. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schreibman P. H., Dell R. B. Human adipocyte cholesterol. Concentration, localization, synthesis, and turnover. J Clin Invest. 1975 May;55(5):986–993. doi: 10.1172/JCI108028. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sims E. A., Danforth E., Jr, Horton E. S., Bray G. A., Glennon J. A., Salans L. B. Endocrine and metabolic effects of experimental obesity in man. Recent Prog Horm Res. 1973;29:457–496. doi: 10.1016/b978-0-12-571129-6.50016-6. [DOI] [PubMed] [Google Scholar]
- Sims E. A. Experimental obesity, dietary-induced thermogenesis, and their clinical implications. Clin Endocrinol Metab. 1976 Jul;5(2):377–395. doi: 10.1016/s0300-595x(76)80027-8. [DOI] [PubMed] [Google Scholar]
- Van R. L., Bayliss C. E., Roncari D. A. Cytological and enzymological characterization of adult human adipocyte precursors in culture. J Clin Invest. 1976 Sep;58(3):699–704. doi: 10.1172/JCI108516. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zinder O., Shapiro B. Effect of cell size on epinephrine- and ACTH-induced fatty acid release from isolated fat cells. J Lipid Res. 1971 Jan;12(1):91–95. [PubMed] [Google Scholar]