Triglyceride storage

Biosynthesis and degradation of glycosaminoglycans biosynthesis of collagen, mineralization and demineralization of bone. Fatty acid synthesis and triglyceride storage in adipocytes promoted by insulin and triglyceride hydrolysis and fatty acid release stimulated by glucagon and adrenaline (epinephrine). 

In rodents taken as animal models, the cholesterol pool of adipose tissue is present in unesterified form and localized to the bulk triglyceride storage droplets. The cholesterol content increases with age, diet, and state of obesity. 

The quaHty, ie, level of impurities, of the fats and oils used in the manufacture of soap is important in the production of commercial products. Fats and oils are isolated from various animal and vegetable sources and contain different intrinsic impurities. These impurities may include hydrolysis products of the triglyceride, eg, fatty acid and mono/diglycerides proteinaceous materials and particulate dirt, eg, bone meal and various vitamins, pigments, phosphatides, and sterols, ie, cholesterol and tocopherol as weU as less descript odor and color bodies. These impurities affect the physical properties such as odor and color of the fats and oils and can cause additional degradation of the fats and oils upon storage. For commercial soaps, it is desirable to keep these impurities at the absolute minimum for both storage stabiHty and finished product quaHty considerations. 

TRIACYLGLYCEROLS (TRIGLYCERIDES) ARE THE MAIN STORAGE FORMS OF FATTY ACIDS... 

Intravenous lipid emulsion particles are hydrolyzed in the bloodstream by the enzyme lipoprotein lipase to release free fatty acids and glycerol. Free fatty acids then are be taken up into adipose tissue for storage (triglycerides), oxidized to energy in various tissues (e.g., skeletal muscle), or recycled in the liver to make lipoproteins. 

Increase in lipogenesis (formation of triglycerides, the storage form of lipids)... 

Although glycogenesis has been shown to follow the administration of some synthetic triglycerides of even-numbered fatty acids, it was shown above that this only occurs with triglycerides incapable of storage in the animal body, and then only to an amount corresponding to that which would be produced by the glycerol moiety of the fat. 

Figure 5.15 GALDI mass spectra of (a) linseed oil (35 years airtight storage from THF solution) and (b) linseed oil as in (a) after 2 weeks of natural ageing (from THF solution). Signal groups of free fatty acids, their oxidation products, and monoglycerides (m/z <500) can be distinguished from diglycerides (m/z 500 800), and triglycerides (m/z 800 1000) (see Table 5.7)...

Fats and oils, constituted by acylglycerolipids, represent a major subgroup of lipids. They are the most common class of medium-size molecules produced by living organisms. They are the main constituents of the storage fat cells in plants and animals. They have quite a similar chemical composition, as they are mainly composed of triglycerides, triesters of glycerol with fatty acids (FAs). 

Adipose Adipose tissue is the primary storage facility for fat. Fat is stored in these tissues as an intracellular droplet of insoluble triglyceride. A hormone-sensitive lipase mobilizes triglyceride stores by hydrolysis to free fatty acids. 

The formation of a triglyceride that requires the presence of glycerol introduces a carbohydrate requirement for the storage of fat. When... 

K38. Kronenberg, F., Lobenstanz, E.-M., Konig, P., Utermann, G., and Dieplinger, H., Effect of sample storage on the measurement of lipoprotein(a), apolipoproteins B and A-IV, total and high density lipoprotein cholesterol and triglycerides. J. Lipid Res. 35, 1318-11328 (1994). 

In adipose tissue, insulin stimulation suppresses triglyceride hydrolysis (to free fatty acids and glycerol) by activating cAMP phosphodiesterase (cAMP PDE). Cyclic AMP, (3, 5 cAMP), is required to stimulate hormone sensitive lipase (HSL), the enzyme which hydrolyses triglyceride within adipocytes PDE converts active 3, 5 cAMP to inactive 5 AMP thus preventing the stimulation of HSL. The net effect of insulin on lipid metabolism is to promote storage. 

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