Reducing cholesterol levels

At the 11th Brazilian Chemical Engineering Congress a paper was presented on the use of quillaja to reduce the cholesterol content of 

Proceeding in the usual way, we discover that the quadratic model is superior to the hnear one. It shows no evidence of lack of fit at the 95% confidence level and explains 94.3% of the variation about the average. The analysis of variance shows that only the terms involving quillaja concentration and pH are significant, which reduces the model to the equation 

The most important coefficients are those of the linear terms, which have opposite algebraic signs — negative for quillaja concentration and positive for pH. Since we want to reduce the cholesterol content, these values teU us that we should increase quillaja concentration and lower the pH value (i.e., use a more acidic medium). However, since the interaction and the quadratic terms are also significant, interpreting these results is more complicated. 

Once more, the quadratic model is found superior to the linear one. It does not present evidence of lack of fit and explains 84.9% of the variation. 

Central composite design to study cholesterol reduction in butter oil 

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Brewers and bakers dried yeasts are used as dietary supplements. They contribute some protein and trace minerals, and some B vitamins, but no vitamin C, vitamin B 2 or fat-soluble vitamins. The glucose tolerance factor (GTE) of yeast, chromium nicotinate, mediates the effect of insulin. It seems to be important for older persons who caimot synthesize GTE from inorganic dietary chromium. The ceU wall fraction of bakers yeast reduces cholesterol levels in rats fed a hypercholesteremic diet. 

Often you need to carry forward data to a specific time point due to holes or sparseness of data. The previous example on determining baseline cholesterol level provides an excellent context for this problem. Assume that you have several cholesterol readings of HDL, LDL, and triglycerides for patients before they take an experimental pill designed to reduce cholesterol levels. For each cholesterol parameter, you want the last observation carried forward so long as the measures occur within a five-day window before the pill is taken. Here are some sample data that illustrate the problem ... 

Lasofoxifene is a SERM that also protects from bone loss, reduces cholesterol levels, and exerts a positive effect on bone strength in rats, specifically in male models (Ma et al. 2002). This compound is in the final stages of clinical development. Two other SERMs also in advanced phase III trials are bazedoxifene and arzoxifene, both with protective effects against ovariectomy-induced bone loss. Arzoxifene has shown both bone remodeling reduction with positive effects on bone quality as well as a reduction in cholesterol levels in oophorectomized rats (Biskobing2003). 

Tea (Camellia sinensis) is one of the most frequently consumed beverages in the world and, consequently, an important agricultural product [168], It has been proved many times that tea may reduce cholesterol level, hypertension, and shows antioxidant and anti-microbial effects [169], Because of its importance, a considerable number of analytical methods have been developed for the separation and quantitative determination of the constituents of tea [170,171]. Thus, the application of high-speed counter-current chromatography [172,173], and HPLC-APCI-MS [174] have been reported. 

Oximes of certain sterols were examined as inhibitors of cholesterol biosynthesis, by suppressing two enzymes that are involved in the biochemical pathway of cholesterol biosynthesis. This dual activity indicates a promising series of biologically reactive oximes (and oxime ethers) capable of reducing cholesterol levels . 

Several studies have discussed the relationship between serum cholesterol and suicide, violence, anxiety disorders, depressive disorders, and schizophrenia [1-3]. Some of these papers suggested that low or lowering cholesterol levels could cause or worsen depressive symptoms and increase the risks of suicide and violence death. There are many reports that discussed the relationships between the lipid profiles, depression, and suicide from the viewpoints of decreased serotonergic transmission on suicide behavior [4, 5], lower serum cholesterol and serotonin levels [6, 7], serum cholesterol levels and polymorphism in the promoter region of the serotonin transporter gene for depression and suicide [8-10], low serum cholesterol and suicide risk [11, 12], and serotonergic receptor function [13, 14]. These studies supported the hypothesis that reduced cholesterol levels resulted in reduced central serotonin transmission. 

Elevated levels of cholesterol in the blood, or hypercholesterolemia, have been linked to heart disease. Cholesterol, a necessary component of all cell membranes, is available to the body by two routes through the diet and through synthesis by the body itself. When changes to one s diet fail to reduce cholesterol levels, medication that inhibits cholesterol biosynthesis may be necessary. The biosynthetic pathway for cholesterol synthesis starts with acetyl-CoA (2.15) (Scheme 2.3). Through a series of steps, three... 

Solvent-free enzymatic interesterification of milk fat alone or with other fats or fatty acids provides the most acceptable route for modification of the triacylglycerol structures in milk fat and further research and development in this field is expected to provide physical and physiological benefits. From a nutritional perspective, it is of interest to examine the effects of randomized milk fat on serum cholesterol. Christophe et al. (1978) reported that substitution of native milk fat with chemically-randomized interester-ified milk fat reduced cholesterol levels in man. However, others found that there was no effect on serum cholesterol levels in man as a result of substitution of ezymatically randomized milk fat (De Greyt and Huyghebaert, 1995). Further studies are required to determine if interesterilied milk fat provides a nutritional benefit. 

Numerous studies have determined that a diet low in saturated and trans fats can typically reduce cholesterol levels from 5 to 8 percent. That s a good start, of course, but many men and women will need to do more. As noted, however, cutting too far back on fat and protein and eating a diet heavily dominated by plant-based foods may lower the total and the LDL cholesterol, but HDL and triglycerides will be adversely affected. Remember that the ratio of total to HDL cholesterol is a better predictor of heart disease risk than either total or LDL cholesterol. 

Not all epidemiology is observational, and experimental studies have a role to play in evaluating the efficiency of an intervention program to prevent disease (e.g., fluoridation of water). An intervention study at one extreme may closely resemble a clinical trial with individuals randomly selected to receive some form of intervention (e.g., advice on reducing cholesterol levels). However, in some instances it may be a whole community that is selected to form the intervention group. The selection may or may not be random. 

At the University of Toronto, studies examining specific dietary effects related to lowering blood cholesterol show that people adhere to a prescribed diet more faithfully and have reduced cholesterol levels when strawberries are included in daily meals. Such diets incorporate fruits, vegetables, soy products, prebiotic fiber (such as from oatmeal), plant sterols, and nuts. Look for references to this work in Appendix D and more information in Part III on the Portfolio diet... 

In addition, Serenoa has been found to reduce cholesterol levels within prostatic tissue. This is notable because higher levels of this substance are found in prostate glands with cancer than in those without. Saw palmetto also contains an acylglyceride, 1-monolaurin, which has shown mild activity against one type of prostatic cancer cell in laboratory experiments. Hence, the use of saw palmetto, as well as nettle root (Urtica dioica), pygeum (Prunus africanum), and pumpkin seed, may offer hope and protection to our aging male population. 

A combination of bile acid sequestrants with nicotinic acid or probucol or an HMG-CoA reductase inhibitor can be used to produce synergistic effects in lowering plasma lipoprotein levels, particularly LDL. The efficacy of drug treatment was shown in a recent study in which lovas-tatin and colestipol were used to reduce cholesterol levels in men with CHD. The rate of progression of coronary lesions was decreased and that of regression increased. These changes also were associated with reduced cardiovascular abnormalities. 

Huang et al. (1993) cite many studies that demonstrate that n-6 fatty acid are able to reduce the level of cholesterol in the blood serum. The data of Horrocks and Harder (1993) showed that n-6 fatty acids and n-3 fatty acids differ in their mode of action in cholesterol reduction, such that n-6 fatty acids redistribute cholesterol and n-3 fatty acid actually reduces the level of cholesterol. Davis (1992) demonstrated that n-3 essential fatty acids are more effective in reducing cholesterol levels in macrophages than n-6 essential fatty acids, most probably by the differential effect on the enzyme acyl-CoA (cholesterol acyltransferase). However, Horrocks and Harder (1983) indicated that cholesterol-esterifying enzymes that incorporate free fatty acids into cholesterol esters without the participation of CoA are also present in the rat brain. 

Two different classes of drugs that are in current use to reduce cholesterol levels in the blood have been discussed in detail in this chapter. What are the names of these two drug classes How does each class act to lower blood cholesterol levels ... 

During the more than two decades that pectin research has been carried out, two areas of investigation with potential benefit to human health have been in lipid metabolism (Table II) and carbohydrate metabolism (Table III). Pectin has been shown to decrease serum cholesterol in humans (6-11) as well as other animal species (10). High levels of serum cholesterol are generally considered to be a risk factor associated with ischemic heart disease (11-13). Consumption of pectin to reduce cholesterol levels in the blood might be expected to reduce the incidence of heart disease especially when serum cholesterol is elevated. 

Compactin and lovastatin are natural statins used clinically under the trade names Zocor and Mevacor . Atorvastatin (Lipitor) , a synthetic statin, is now the most popular statin. Lipitor has greater potency and a longer half-life than natural statins have, because its metabolites are as active as the parent drug in reducing cholesterol levels. Therefore, smaller doses of the drug may be administered. The required dose is reduced further because Lipitor is marketed as a single enantiomer. In addition, it is more lipophilic than compactin and lovastatin, so it has a greater tendency to remain in the endoplasmic reticulum of the liver cells, where it is needed. 

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