Blood cholesterol lowering

Soybean tocopherols are the major source of natural fat-soluble antioxidants and Vitamin E. The Vitamin E activity of natural d-cx-tocopherol is much greater that that of synthetic Vitamin E, which is a mixture of eight stereoisomers (203). Phytosterols are used as raw materials for over 75% of the world s steroid production. The more recent application of phytosterol, phytostanol, and their fatty acid esters in margarine and table spreads is based on the blood cholesterol-lowering effect of these compounds (204,205). The recent development of functional foods containing phytosterols has been reviewed by Hollingsworth (206) and Hicks and Moreau (207). 

Meijer, G.W. (1999) Blood cholesterol-lowering plant sterols types, doses and forms. Lipid Technol., November 1999, 129-132. 

Applications include increased blood cholesterol lowering potency in the tetrazolyl analog of nicotinic acid and improved stability of certain dicarboxylic penicillins in which one carboxyl function has been replace by tetrazol. 

Chltosan is being considered as a possible blood cholesterol lowering agent. Only at levels above 5% in the diet of rats does chltosan and its parent compound chitin appear to cause harmful effects. As commercially available, neither compound can be considered homogenous. Extensive cleaning and standardization of both materials, and specifically chltosan, may be necessary for future evaluation. Results observed in this study can possibly be attributed to some unknown consti-tuent(s) in chitin or chltosan, as may be the case when using natural products. 

Blood-cholesterol-lowering agents—It is suspected that the types of these drugs which bind with cholesterol and bile salts in the intestine may similarly tie up calcium and other minerals so that their absorption is reduced. 

Other soluble fiber-containing products have been shown to lower blood cholesterol. Recent extensive studies on psyllium (Plantago ovata) presented both as a pharmaceutical preparation and as a food product (a ready to eat breakfast cereal) have shown blood cholesterol-lowering properties where the dose-effect relationship is such that a useful additional therapeutically meaningful lipid-lowering effect can be achieved by prescribing a daily portion of psyllium-fortified breakfast cereal. Products of this type are now marketed in the US and Australia, and the US FDA has now allowed a food specific health claim for psyllium. 

There is also a small literature on the effects of beans on blood lipids and the findings of a blood cholesterol-lowering effect are as expected. 

Guanfacine. Guanfaciae, used ia patients having mild to moderate hypertension, can lower blood pressure 50/25 mm Hg (systoHc/diastoHc) ia hypertensive patients. Side effects such as sedation, dry mouth, and asthenia are less as compared to those of guanaben2 and clonidine. Guanfaciae reduces blood cholesterol and triglyceride and does not cause glucose iatolerance. 

Many valuable compounds are aromatic in part, including steroids such as estrone and well-known pharmaceuticals such as the cholesterol-lowering drug alorvastatin, marketed as Lipitor. Benzene itself has been found to cause bone marrow depression and a consequent lowered white blood ceil count on prolonged exposure. Benzene should therefore be handled cautiously if used as a laboratory solvent. 

Cold-water frsh like salmon are rich in omega-3 fatty acids, which have a double bond three carbons in from the noncarboxyl end of the chain and have been shown to lower blood cholesterol levels. Draw the structure of 5,8,11,14,17-eicosapentaenoic acid, a common example. (Eicosane = C20H42)... 

An increase in serum lipids is believed to contribute to or cause atherosclerosis, a disease characterized by deposits of fatty plaques on the inner walls of arteries. These deposits result in a narrowing of the lumen (inside diameter) of the artery and a decrease in blood supply to the area served by the artery. When these fatty deposits occur in the coronary arteries, the patient experiences coronary artery disease. Lowering blood cholesterol levels can arrest or reverse atherosclerosis in the vessels and can significantly decrease the incidence of heart disease. 

Emphasizes that drug therapy alone will not significantly lower blood cholesterol levels. 

The larger the benefit, the smaller the number of subjects required to show statistical significance. For example, if a herbal supplement is expected to produce a 5% lowering of the blood cholesterol level vs placebo, this will require many more subjects than a study evaluating the effects of a drug that is expected to produce a 50% reduction vs placebo. 

Pectin, the substance that makes jellies and jams so jelly-like, can help lower blood cholesterol levels by forcing the body to make more bile acids. Pectin is a type of fiber, and like most fiber, pectin cannot be digested by the human body. Instead, the fiber moves slowly through the small intestines. When pectin encounters sugar and acid, its molecules trap water within its long chains, turning into a gel-like mass. This gel traps and eventually eliminates bile acids from the gut. When this happens, the body must make more bile acids, reducing the amount of cholesterol in the blood. 

Pectin is found in apples and in the white membrane that surrounds the sections of oranges, grapefruits, or other citrus fruits, as well as in several other sources. Powdered pectin made from apple cores is also available, but scientists have found that eating apples or citrus fruit has a much better effect on lowering blood cholesterol levels than eating powered pectin does. They believe eating the whole fruit is better because the body also needs vitamin C to convert cholesterol into bile acids. Fruits contain vitamin C, or ascorbic acid, but the powdered pectin does not. 

When dietary fibre became a nutrition issue it was assumed that the insoluble fibre such as bran was the most beneficial subcomponents. It now appears that soluble fibres can lower blood cholesterol while insoluble fibre such as wheat bran merely speeds up the transit of food through the gut. Developments in this area are awaited. 

Which of the following drugs recommended for the lowering of blood cholesterol inhibits the synthesis of cholesterol by blocking 3-hydroxy-3-me thy 1 glutary 1-coenzyme A (HMG-CoA) reductase ... 

The answer is d, (Hardman, pp 934-935.) Chenodeoxycholic acid (chenodiol) and ursodiol have proved to he effective in some patients with cholesterol gallstones. Lovastatin lowers blood cholesterol levels but has no effect on gallstones. Methyl tertiary butyl ether and a new agent, monoctanoin, are infused directly into the common duct and will dissolve gallstones. 

Estrogens are thought to exert their cardiovascular effects by acting on blood lipoproteins or by direct effects on blood vessels. In studies performed in rats, fulvestrant had no effect on plasma cholesterol levels. When administered along with estradiol, however, it blocked the cholesterol-lowering activity of estradiol (Lundeen et al. 1997). 

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