Theophrastus and the name of Artichoke.

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Artichoke Extract Health Benefits:6.Cardiovascular protection.

Artichoke leaf Extract INCI Name Cynara Scolymus Extract CAS 84012-14-6 EINECS ELINCS No 281-659-3 Artichoke thistle extract photo picture image The discovery that artichoke leaf extract reduces elevated cholesterol levels opens up exciting perspectives in the prevention and treatment of arteriosclerosis and coronary heart disease.

 It was as early as the 1930s that scientists first discovered that artichoke extract had a favorable effect on atherosclerotic plaques in the arteries (Tixier, 1939). Later animal studies, in which rats were fed a high-fat diet, also showed that artichoke extract prevented a rise in serum cholesterol levels and the manifestation of atherosclerotic plaque (Samochowiec, 1959 and 1962).

 In addition to findings in animal experiments (Frohlich and Ziegler, 1973; Samochowiec et al., 1971; Wojcicki 1976 and 1978; Samochowiec 1959 and 1962; Lietti 1977), a number of early case reports and uncontrolled studies indicated clinical effectiveness of the artichoke extract on human cholesterol levels (Hammerl and Pichler 1957, Hammerl et al., 1973).

 Recent research confirms these earlier findings. The above mentioned study by Fintelmann demonstrated a significant reduction in cholesterol and triglyceride levels in spite of the relatively short duration of the study (6 weeks). On an average there was an 11.5% reduction in serum cholesterol, from 264 mg/dl initially to 234 mg/dl. Serum triglycerides were similarly reduced from 215 mg/dl initially to 188 mg/dl, corresponding to a decrease of 12.5%. Although this was an open study, its reliability is buttressed by the relatively large number of patients (302) and the very high level of statistical significance attained for the main results.

 Very interesting results came out of an excellent double blind clinical trial, conducted by Petrowicz in 1996. It studied the cholesterol-lowering effect of artichoke leaf extract on 44 healthy individuals under strictly controlled conditions over a 12-week period. There was a significant decrease of cholesterol levels in the volunteers who had high initial levels (greater than 220 mg/dl). In fact, the higher the initial cholesterol value, the more significant was the reduction in cholesterol levels. It was also observed that the protective HDL cholesterol levels showed a tendency to increase.

 Although the cholesterol-lowering effect of artichoke extract has been known for a few decades, the mechanism behind it has not been clear. Current research is increasing our understanding in this respect.

 Artichoke extract has been found to affect the cholesterol metabolism in two different ways. It not only increases the breakdown of cholesterol to bile salts and enhances their elimination through increased bile production and flow; it also inhibits the internal production of cholesterol in the liver.

 The inhibiting effect of artichoke leaf extract on cholesterol synthesis was demonstrated in some very interesting studies by Gebhardt (1995, 1996 and 1997) on rat hepatocytes (liver cells). A highly significant concentration-dependent inhibition of cholesterol synthesis was found. The 1997 study indicates that artichoke leaf extract reduces the formation of cholesterol in a physiologically favorable, long-lasting manner. This reduction of cholesterol synthesis persisted for hours following the period of exposure.

 The study further indicates that artichoke extract may work through indirect inhibition of the enzyme HMGCoA-reductase, which might avoid problems known to occur with strong direct inhibitors of HMGCoA-reductase during long-term treatment. The indirect inhibition was supported by the fact that artichoke leaf extract effectively blocked insulin-dependent stimulation of HMGCoA-reductase without affecting insulin in general. HMGCoA-reductase is a key enzyme in cholesterol synthesis, and HMGCoA-reductase inhibitors generally reduce total cholesterol, LDL cholesterol and triglyceride levels.

 Another important observation in Gebhardt's study was that the extract did not interfere with other stages of the pathway leading to cholesterol synthesis, which is why adverse effects due to accumulation of sterol precursors are not to be expected. The study also revealed that the components of the extract responsible for its cholesterol-inhibiting effect are chlorogenic acid, cynaroside and particularly luteolin. Cynarin, which for a long time was believed to be the active principle in this respect, seems instead to have its main influence on the bile promoting and hepato-protective mechanisms.

 The importance of these studies becomes clear when we take a look at the health situation in America today. It is an astounding fact that approximately 50% of American adults (100 million people) have high (>240 mg/dl) or borderline-high (200-239 mg/dl) serum levels of total cholesterol. It is also a disconcerting fact that an estimated two thirds of these people do not receive any form of therapy, according to the National Heart, Lung and Blood Institute. High cholesterol levels are universally accepted as a major risk factor for coronary heart disease (CHD), and there is strong evidence from large clinical trials according to the American Heart Association, that reduction of cholesterol levels benefits patients with CHD.

 Coronary heart disease is the single leading cause of death in America today. Statistics estimate 1,100,000 cases of new and recurrent coronary attacks per year in America, and one third will lead to death. High mortality, widespread personal suffering as well as a substantial economical impact on the total cost of our health care systems, demand multiple approaches to this devastating situation.

 What is cholesterol?

 Cholesterol is a form of fat or lipid. We get it in two ways: externally from the food we eat, and internally from our own normal metabolic processes. Although a high blood level is a risk factor for coronary heart disease, it does not mean that cholesterol is altogether bad. Cholesterol is necessary for the body to function properly. It is, for example, used to build cell membranes and to manufacture sex hormones. There is the so-called "good" cholesterol, known as HDL cholesterol, and the "bad" form known as LDL cholesterol. The terms HDL and LDL refer to the lipoprotein carriers of cholesterol in the blood.

 The measurement of total cholesterol in the blood includes low-density lipoprotein (LDL) cholesterol and high-density lipoprotein (HDL) cholesterol. The oxidized LDL form is very damaging to our arteries. HDL cholesterol, on the other hand, is beneficial for us. The American Heart Association currently recommends that LDL cholesterol levels should be under 130 mg/dl, HDL cholesterol should be above 35 mg/dl and total cholesterol should be under 200 mg/dl. The total cholesterol-to-HDL ratio should be no higher than 4, and the LDL-to-HDL ratio should be no higher than 2.5. The risk of heart disease can be reduced by raising HDL cholesterol as well as lowering LDL cholesterol.

 How do we raise HDL cholesterol? It has actually been shown that regular exercise is an effective way to raise HDL cholesterol. Exercise is one of the non-drug therapies recommended by the American Heart Association. Physical inactivity is shown to be a clear risk factor for CHD, while regular exercise 3-4 times a week can help control both lipid levels, hypertension and overweight problems.

 The lowering of LDL cholesterol, however, has more to do with diet. Consumption of hydrogenated oils, saturated fats, alcohol and high sugar intake interfere with normal cholesterol metabolism and raise the blood levels of LDL cholesterol. The lack of important nutrients found in vegetables and fruits also play a role in this regard. The American Heart Association offers detailed recommendations for a healthy diet in its program for prevention and treatment of coronary heart disease. It does little good, however, to eat a low cholesterol diet if we are overproducing cholesterol internally or not removing it from the blood at the normal rate. Normal bile production and bile flow are therefore of crucial importance for a balanced cholesterol metabolism.

 When a healthy lifestyle is not enough to keep cholesterol levels within an acceptable range, drug therapies are usually offered. A variety of cholesterol-reducing pharmaceutical drugs have been developed, such as fibric acids (Lopid), bile acid sequestrants (Questran), nicotinic acid (Niacin), and HMG-CoA reductase inhibitors (Lipitor, Mevacor, Pravachol, Zocor and others), some of which unfortunately have very serious side effects. More therapeutic options are urgently needed.

 There is evidence enough to support artichoke leaf extract as a gentle, non-toxic aid and adjunct to other therapies in the prevention and treatment of high cholesterol levels and coronary heart disease. Further research and well-designed controlled clinical studies are of course needed to clarify in detail the lipid-lowering mechanisms and further evaluate potential efficacy and safety. Its safety profile and demonstrated efficacy suggest that artichoke leaf extract fills an important gap.

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citations1.Theophrastus and the name of Artichoke.

last edit date:1st,July.2009.