Triglyceride concentration, reduction

Increased intake of soluble fiber in the form of oat bran, pectins, certain gums, and psyllium products can result in useful adjunctive reductions in total and LDL cholesterol (5% to 20%), but these dietary alterations or supplements should not be substituted for more active forms of treatment. They have little or no effect on HDL-C or triglyceride concentrations. These products may also be useful in managing constipation associated with the bile acid resins (BARs). 

Interferon alfa often affects lipid metabolism and produces a reversible reduction in cholesterol and, more consistently, increases in triglyceride concentrations (SEDA-20, 328 SEDA-21, 371). Meticulous blood lipid investigation showed a significant rise in serum triglyceride and lipoprotein ) concentrations and reductions in total cholesterol, HDL cholesterol, LDL cholesterol, and apoprotein Al. 

Recently, resveratrol was found to reverse fat-induced insulin resistance [McCarty, 2005]. This observation provides more enthusiasm for researchers to use resveratrol as an antidiabetic agent. Su and associates [2006] showed that resveratrol significantly reduced the plasma glucose concentration as well as the dramatic reduction of triglyceride concentration in streptozotocin (STZ)-induced diabetic mellitus rats in 14 days treatment. They concluded from this observation that resveratrol possesses hypoglycemic and hypolipidemic properties [Su et al., 2006]. Baur et al., [2006] added more value to this conclusion by showing that resveratrol increases insulin sensitivity by lowering the blood... 

Alterations in lipid metabolism are common and include increases in serum triglyceride and cholesterol concentrations, sometimes persisting after withdrawal of the therapy, and reductions in high-density lipoprotein cholesterol. The incidence of raised serum lipids during therapy with oral isotretinoin 1 mg/kg/day for acne has been reviewed retrospectively in 876 patients, of whom 54 had raised serum cholesterol concentrations (over 5.2 mmol/1) and 45 had triglyceride concentrations above 2.26 mmol/1 (57). 

The total serum lipid concentration is reduced by physical conditioning serum cholesterol may be lowered by as much as 25%. HDL cholesterol, however, is increased. Thus the decrease in total cholesterol concentration is mostly due to a reduction in low-density lipoprotein (LDL) cholesterol. The concentration of serum apolipoprotein A-1 increases with training, whereas the concentration of apolipoprotein B decreases. The serum triglyceride concentration may be reduced by up to 20mg/dL (0.23mmoI/L), but the free fatty acid concentration is higher in fit individuals than others. Loss of body fat is associated with improvement in hpid concentrations. The lactate response to exercise is... 

A. Mectianism and Effects Niacin (but not nicotinamide) directly reduces the secretion of VLDL fixjm the liver (Figure 35-2) and inhibits hepatic synthesis of apolipoproteins or cholesterol. Consequently, LDL formation is reduced and there is a decrease in LDL cholesterol (Table 35-3). Increased clearance of VLDL by lipoprotein lipase in the periphery has also been demonstrated and probably accounts for the reduction in serum triglyceride concentrations. In addition, the levels of HDL may increase. Finally, niacin decreases circulating fibrinogen and increases tissue plasminogen activator. 

A. Mechanism and Effects Fibric acid derivatives (eg, gemfibrozil, fenofibrate, clofibrate) are ligands for the peroxisome proliferator-activated receptor-alpha (PPAR-a) protein, a receptor that regulates transcription of genes involved in lipid metabolism. Tbis interaction with PPAR-a results in increased activity of lipoprotein lipase and enhanced clearance of triglyceride-rich lipoproteins (Figure 35-2). Cholesterol biosynthesis in the liver is seeondarily reduced. The fibrates reduce serum triglyceride concentrations (Table 35-3). There may be a small reduction in LDL cholesterol and a small increase in HDL levels. 

Four patients had type Ila hyperlipoproteinemia characterized by an elevation of serum cholesterol concentrations with normal serum triglyceride concentrations this represents a selective elevation of the LDL. These patients with hypercholesterolemia alone responded better to the bean diet than did six other patients. These six patients had type Ilb hyperlipoproteinemia characterized by an elevation of both serum cholesterol and triglyceride concentrations reflecting abnormally high LDL and very low density lipoproteins (VLDL) concentrations. Thus the four patients with type Ila hyperlipoproteinemia had a 24% reduction In serum total cholesterol concentration with values decreasing from 314 to 239 mg/dl their LDL cholesterol concentrations decreased by 27%. The six patients with type lib hyperlipoproteinemia had a 16% decrease In serum total and a 19% decrease In LDL cholesterol concentrations. He will need to study more patients to determine If these different responses are consistent and have Important therapeutic Implications. 

Fatty acids derived from animal and vegetable sources generally contain an even number of carbon atoms siace they are biochemically derived by condensation of two carbon units through acetyl or malonyl coenzyme A. However, odd-numbered and branched fatty acid chains are observed ia small concentrations ia natural triglycerides, particularly mminant animal fats through propionyl and methylmalonyl coenzyme respectively. The glycerol backbone is derived by biospeciftc reduction of dihydroxyacetone. 

PLTP is responsible for the majority of phospholipid transfer activity in human plasma. Specifically, it transfers surface phospholipids from VLDL to HDL upon lipolysis of triglycerides present in VLDL. The exact mechanism by which PLTP exerts its activity is yet unknown. The best indications for an important role in lipid metabolism have been gained from knockout experiments in mice, which show severe reduction of plasma levels of HDL-C and apoA-I. This is most likely the result of increased catabolism of HDL particles that are small in size as a result of phospholipid depletion. In addition to the maintenance of normal plasma HDL-C and apoA-I concentration, PLTP is also involved in a process called HDL conversion. Shortly summarized, this cascade of processes leads to fusion of HDL... 

A molecular variation of plasma membrane has been reported by Puccia et al. Reduction of total lipids (XL) content and significant variations of triglyceride (TG) and phospholipids (PL) fractions were observed as a consequence of exposure of C. intestinalis ovaries to TBTCl solutions. In particular, an evident TG decrease and a PL increase were observed, which probably provoked an increment in membrane fluidity, because of the high concentration of long chain fatty acids and, as a consequence, PL. This could be a cell-adaptive standing mechanism toward the pollutants, as observed in Saccharomyces cerevisiae. Also the increase in the content of the polyunsaturated fatty acids (PUPA), important in the synthesis of compounds such as prostaglandin which are present in the ovary in a stress situation, was probably a consequence of a defense mechanism to the stress provoked by the presence of TBTCl. 

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