Tag Archives: HDL

Lipid profile or Lipid panel

Definition:
A complete cholesterol test — also called a lipid panel or lipid profile: — It is a blood test that can measure the amount of cholesterol and triglycerides in your blood. A cholesterol test can help determine your risk of atherosclerosis, the buildup of plaques in your arteries that can lead to narrowed or blocked arteries throughout your body. High cholesterol levels usually don’t cause and signs or symptoms, so a cholesterol test is an important tool. High cholesterol levels are a significant risk factor for heart disease.

An extended lipid profile may include very low-density lipoprotein. This is used to identify hyperlipidemia (various disturbances of cholesterol and triglyceride levels), many forms of which are recognized risk factors for cardiovascular disease and sometimes pancreatitis.

It is recommended that healthy adults with no other risk factors for heart disease be tested with a fasting lipid profile once every five years. Individuals may also be screened using only a cholesterol test and not a full lipid profile. However, if the cholesterol test result is high, there may be the need to have follow-up testing with a lipid profile.

 

..CLICK TO SEE THE PICTURES>..(1)..(2)....(3)..…...(4)…….(5)....(6).

If there are other risk factors or the individual has had a high cholesterol level in the past, regular testing is needed and the individual should have a full lipid profile.

For children and adolescents at low risk, lipid testing is usually not ordered routinely. However, screening with a lipid profile is recommended for children and youths who are at an increased risk of developing heart disease as adults. Some of the risk factors are similar to those in adults and include a family history of heart disease or health problems such as diabetes, high blood pressure (hypertension), or being overweight. High-risk children should have their first lipid profile between 2 and 10 years old, according to the American Academy of Pediatrics. Children younger than 2 years old are too young to be tested.

A total cholesterol reading can be used to assess an individual’s risk for heart disease, however, it should not be relied upon as the only indicator. The individual components that make up total cholesterol reading –- LDL, HDL, and VLDL –- are also important in measuring risk.

For instance, one’s total cholesterol may be high, but this may be due to very high good (HDL) cholesterol levels –- which can actually help prevent heart disease. So, while a high total cholesterol level may help give an indication that that there is a problem with cholesterol levels, the components that make up total cholesterol should also be measured.

The “lipid profile” is a popular component of master health check ups.There is no ideal age for the first evaluation. Elevated levels have been found in children as young as two if there is a history of adults in the family having elevated lipids or early heart attacks. Genetic studies have consistently shown changes in the Apolipoprotein E (APOE) locus in affected families. But for this gene to express itself, environmental factors like diet, obesity and inactivity also play a part.

If there is no such family history, lipids should be evaluated for the first time at the age of 20. If the results are “desirable”, the next reading can be taken after five years. In an older person (over 45 in men and 55 in women) the values need to be checked every year.

The blood should be taken after a nine-hour fast (water can be consumed). There should be no fever, infection, inflammation or pregnancy as these can alter the values.

Everyone has fat deposits under the skin, where it serves as insulation against heat and cold. Cholesterol is a fat that is produced by the liver and is essential for normal metabolism. It is not soluble in blood, it is transported through the body by LDL (low density lipoproteins), HDL (high density lipoproteins) and VLDL (very low density lipoproteins). Of these HDL is a “good” lipid as it transports excess cholesterol to the liver for excretion. VLDL and LDL transport cholesterol from the liver back into the blood.

As long as blood cholesterol remains in the normal range, the blood circulates freely. When levels are elevated, it precipitates in the blood vessels, forming obstructive deposits called plaques. This eventually leads to high blood pressure, heart attacks and strokes.

TGL or triglycerides are different from cholesterol. They are derived from food when the calorie intake is greater than the requirement. It combines with cholesterol and gets deposited in the blood vessels.

A person with elevated lipids may develop a yellow deposit of cholesterol under the skin, usually around the eyelids. They may also have a crease on the earlobes.

A fat deposit (lipoma) can appear as a painless mobile lump just under the skin anywhere in the body. When multiple, it is a hereditary condition called multiple lipomatosis. These are not markers for elevated lipids. The lumps are not cancerous but may be cosmetically unacceptable. They do not respond to the lipid lowering medications and need to be surgically removed.

An elevated lipid profile can often be reversed by changes in lifestyle. Quit smoking immediately and drink in moderation only — two drinks a day for men and one for women. The much publicised cardio protective actions of alcohol are outweighed by the other problems of regular drinking.

Try to achieve ideal body weight and bring down the BMI (body mass index, which is found by dividing the weight by the height in metre squared) to 23. This can only be achieved with a combination of diet and exercise. Try to stop snacking, especially on fried items and “ready to eat” snacks. Increase the consumption of fruits and vegetables to 4-6 helpings a day. Walnuts, almonds and fish are rich in protective omega -3 fatty acids and Pufa (poly unsaturated fatty acids). Oats contains dietary fibre. Lower oil consumption to 300ml per month per family member. Try to use olive oil. If that is not practical or feasible, use a mixture of equal quantities of rice bran oil, sesame oil, mustard oil and groundnut oil.

Exercise aerobically (walking, running, jogging or swimming) for 60 minutes a day. This need not be done at one stretch but can be split into as many as six 10-minute sessions.

If lipids are still elevated after 3-6 months despite these interventions, speak to your physician about regular medication.

The “statin” group of drugs are very effective. They lower cholesterol, prevent its deposition and stabilise the plaques in the blood vessels. They can be combined with other drugs like ezetimibe (which limit the absorption of cholesterol), or bile acid binding resins, or niacin or fibrates. Natural supplements of fish oil or pure omega-3 fatty acid capsules also help. Lipid lowering medications are usually well tolerated and very effective.

Resources:
http://www.mayoclinic.com/health/cholesterol-test/MY00500
http://en.wikipedia.org/wiki/Lipid_profile
http://www.telegraphindia.com/1120730/jsp/knowhow/story_15788559.jsp

Enhanced by Zemanta
Advertisements

Researchers Make Synthetic HDL Cholesterol

US researchers have developed a synthetic form of good cholesterol known as HDL they hope will be able to keep levels of bad cholesterol  in check. The compound, which has a tiny core of gold, is manufactured using nanotechnology, and its developers think it has the potential to rid the body of excess bad cholesterol.

lipoprotein (HDL) particles like the one depicted here nevertheless incorporate large proteins that are difficult to mimic artificially.This is required  to  treat atherosclerosis.

.
“The idea is you take this and effectively just urinate it out,” said Chad Mirkin of Northwestern University in Chicago. Mirkin, director of Northwestern’s International Institute for Nanotechnology said, “The molecule mirrors the size and structure of high-density lipoprotein, or HDL. It is comprised of a carefully sized gold particle swathed in fat molecules known as lipids and capped off with a protein layer.”

It is designed to attract and trap low-density lipoprotein, or LDL, the bad kind of cholesterol that can build up in arteries and cause heart attacks and strokes. Powerful drugs known as statins can help lower LDL levels, but they do little to raise levels of protective HDL cholesterol.

“The hope is this will be a material that doesn’t have side effects, that allows you to do what the statins don’t do. That is raise the HDL level, which might be able reverse a lot of the damage and plaques that are already there,” Mirkin said.

Current drugs that raise natural levels of HDL, such as niacin, cause unpleasant side effects such as flushing. And while many drug companies are working to develop better HDL-raising drugs, few have succeeded. “HDL is a natural nanoparticle, and we’ve successfully mimicked it,” Mirkin said.

Gold is an ideal scaffolding material because its shape can be easily tailored, and it is non-toxic, making it a good drug candidate. Mirkin said “Gold is already used in therapies for arthritis and as contrast agent in imaging.”

Mirkin is testing the synthetic HDL molecules in animals. “Will they bind to cholesterol and effectively lower cholesterol, and will they reverse the damage of plaques? That would be absolutely spectacular,” he said. Analysts believe the market potential for HDL-raising drugs is well over $10 billion.

Current HDL-raising drugs include Abbott Laboratories Inc’s Niaspan, which also lowers a type of blood fat called triglycerides. In Europe, Merck & Co markets a drug called Tredaptive that combines niacin with an anti-flushing agent. Merck is already well into development of an HDL-raising drug called anacetrapib and plans to start late-stage trials in humans this year. The drug, also called MK-859, has a similar mechanism of action to a failed compound by Pfizer Inc called torcetrapib that was linked with deaths .

Sources: The Times Of India

Reblog this post [with Zemanta]

‘Good Cholesterol’ Might Not be Good

Is ‘good cholesterol’ really good for you; not so, suggests a new study.

University of Chicago (U-C) researchers challenged popular notion that simply having high levels of good cholesterol (HDL) and low levels of bad cholesterol (LDL) is necessary for good heath.

Instead, they show that the good cholesterol has varying degrees of quality and that poor quality HDL is actually bad for you.

Cholesterol is a waxy, fat-like substance used by the body to maintain the proper function of cell membranes and is encapsulated within two types of proteins as it travels in the body – low density lipoproteins (LDL) and high-density lipoproteins (HDL).

High levels of LDL or total cholesterol are an indicator of increased risk for heart disease. High blood cholesterol elicits no physical symptoms, making medical screenings necessary for detection.

“For many years, HDL has been viewed as good cholesterol and has generated a false perception that the more HDL in the blood, the better,” said Angelo Scanu, pioneer in blood lipid chemistry from U-C and co-author of the study.

“It is now apparent that subjects with high HDL are not necessarily protected from heart problems and should ask their doctor to find out whether their HDL is good or bad,” he added.

The researchers came to this conclusion after reviewing published research on this subject. They found that the HDL from people with chronic diseases like rheumatoid arthritis, kidney disease, and diabetes is different from the HDL in healthy individuals, even when blood levels of HDL are comparable.

They observed that normal, ‘good’ HDL reduces inflammation, while the dysfunctional, ‘bad’ HDL does not, according to an U-C release.

“This is yet one more line of research that explains why some people can have perfect cholesterol levels, but still develop cardiovascular disease,” said Gerald Weissmann, editor-in-chief of The FASEB Journal, which published the study in its December edition.

“Just as the discovery of good and bad cholesterol rewrote the book on cholesterol management, the realisation that some of the ‘good cholesterol’ is actually bad will do the same,” he added.

US Centres for Disease Control and Prevention said approximately 17% of all American adults have high total cholesterol, putting them at risk for heart disease.

Sources:-The Times Of India

Reblog this post [with Zemanta]

Policosanol

Other names: Octacosanol, 1-Octacosanol, N-Octacosanol, Octacosyl Alcohol

Definition:
Policosanol (or polycosanol) is the generic term for a natural extract of plant waxes. It is used as a nutritional supplement to lower (bad) LDL cholesterol and increase (good) HDL cholesterol and to help prevent atherosclerosis. Independent clinical trials have failed to prove its efficacy.

Physical properties
Policosanol is a mixture of a few fatty alcohols derived from the waxes of such plants as sugar cane and yams, as well as beeswax. The most prevalent alcohol in policosanol is octacosanol, followed by triacontanol.(Formula CH3-(CH2)n-CH2OH n=24-34 )

There is a much lower concentration of several other fatty alcohols: behenyl alcohol, lignoceryl alcohol, ceryl alcohol, 1-heptacosanol, 1-nonacosanol, 1-dotriacontanol, and geddyl alcohol.

Policosanol is marketed by Cuba as a natural way to treat high cholesterol levels.

Modulation of HMG-CoA reductase and bile acid absorption inhibition have been proposed as mechanisms.

Policosanol, a dietary supplement, is a mixture of alcohols isolated from Cuban sugarcane wax. It contains about 60% octacosanol.

Because patent issue and the US trade embargo against Cuba, sugarcane policosanol is not widely available in the United States. Instead, policosanol products sold in the US are generally derived from beeswax and wheat germ.

Studies
Published studies have come to conflicting conclusions regarding the efficacy of policosanol in lowering LDL (i.e., “bad cholesterol”) or raising HDL (i.e., “good cholesterol”). Despite a number of studies funded by the Cuban government (which also produces and markets the drug), no independent clinical trials have found any evidence of the efficacy of Policosanol.

Evidence for Policosanol
Policosanol has been touted as a dietary supplement that can lower cholesterol as well as statin drugs, without the side effects. Studies indicate that it works by inhibiting cholesterol formation in the liver.

However, almost all of the 80+ double-blind studies on sugarcane policosanol were conducted by a single research group in Cuba that owns the policosanol patent.

An independent study published in the Journal of the American Medical Association in 2006 did not find any benefit of policosanol, even at high doses, on cholesterol profile. This finding has casted some doubt on the reliability of the Cuban research on policosanol.

Dosage Information
A typical dosage of policosanol used in studies has been 5 to 10 mg two times a day. Studies generally found that it can take up to two months to notice benefits.

Side Effects of Policosanol
Although the reliability of the Cuban studies has been questioned, side effects of policosanol reported in the trials have generally been mild and short-term. They have included indigestion, skin rash, headache, insomnia, and weight loss.

Possible Drug Interactions
Policosanol may increase the effect of medications that interfere with blood clotting or anti-platelet drugs, such as aspirin, warfarin (Coumadin), heparin, clopidogrel (Plavix), ticlopidine (Ticlid), or pentoxifylline (Trental), or supplements such as garlic, ginkgo, or high-dose vitamin E.

Policosanol may increase the effects and side effects of levodopa, a medication used for Parkinson’s disease.

Production
Policosanol (PPG) is produced, promoted and studied extensively in Cuba, where pharmaceutical research and sugar cane farms both exist in abundance. The supplement is used as a panacea by some Cubans.

Resources:
http://en.wikipedia.org/wiki/Policosanol
http://altmedicine.about.com/od/policosanol/a/policosanol.htm

Reblog this post [with Zemanta]

A Shot for the Heart

Scientists are looking at the possibility of a vaccine for cardiovascular disease.

When it comes to cardiovascular disease, India is either one of the world’s greatest laboratories or killing fields, depending on how you see it. The prevalence rate of this ailment has shot up in the last five decades from 4 per cent to 11 per cent of the population. The World Health Organisation (WHO) predicts that by 2010, 60 per cent of all cardiac patients in the world will be Indians. South Asians are genetically prone to the disease, and should thus greet any new prevention option with enthusiasm. Now there is potential for a new approach at controlling the disease: vaccination.

It is not as if everyone can get vaccinated during childhood and secure lifelong protection from heart disease, although it is not something that can be completely ruled out in the long run. Many scientists the world over are actively pursuing vaccination as a strategy to reduce the risk of heart disease significantly. If all goes well, in four or five years we could see the first vaccine entering the market, and that can decrease certain kinds of cardiovascular risk. “We could start clinical trials for a cardiovascular vaccine in two years,” says Johan Frostegard, a scientist at the Karolinska Institutet in Sweden.

Frostegard and his collaborators at Lund University in Sweden recently discovered a new risk factor for cardiovascular disease: low levels of an antibody against a molecule called phosphorylcholine (PC). These antibodies, called anti-PC, decrease the risk for cardiovascular disease. Some people have large amounts of this antibody, while others do not. Since the discovery is new, people from around the world have not been tested for it. Frostegard knows that Swedes have low levels of the antibody compared to inhabitants of New Guinea who live a traditional life. Cardiovascular disease is rare in such people in New Guinea. Frostegard’s method is to increase anti-PC levels in the blood through vaccination. “A vaccine gives you antibodies you should have had in the first place,” he says.

There have been a few other recent attempts at using vaccination to protect against heart disease. One of them, at the US firm AVANT Immunotherapeutics, uses methods to increase high-density lipoproteins (HDL) in the body. The other strategy, again from Lund University, targets low-density lipoproteins (LDL). Both of these methods are early in their development and have not been tested in clinical trials, and it is not certain if the institutions will try to test them. But both have shown the scientific validity of the vaccination approach at preventing or treating cardiovascular disease.

Cardiovascular disease is complex and has many causes and risk factors. It is not clear if we have discovered all the risk factors, or even the majority of them. Some major risk factors have been known for a long time. These include high blood pressure and diabetes. Two other risk factors were discovered a few decades ago: high levels of LDL and low levels of HDL. Both are cholesterols, and increasing HDL and reducing LDL — through diet or drugs — are now part of all strategies to control cardiovascular disease.

There are other risk factors like high levels of triglycerides whose precise role is not well known. Of late, medical scientists have discovered other risk factors, an important one being a molecule called C-reactive protein.

Although we know the risk factors, cardiologists and researchers are yet to agree on a strategy to fight them effectively. Diet and exercise are the first part of any strategy, and it is well known that they work in some cases, particularly in controlling diabetes and high blood pressure.

However, controlling cholesterol is not so easy with diet and exercise because 80 per cent of the cholesterol is manufactured in the body itself. HDL clearly goes up with exercise, but it may not be enough for people who have very low levels to start with.

This is why a class of drugs called statins has become very popular among cardiologists and patients. Statins reduce LDL and boost HDL, but are toxic for some patients. In this context, a vaccine that can reduce the risk factors would be a safe alternative. For example, Una Ryan and Charles Ritterhaus of AVANT showed two years ago that a vaccine could help to increase HDL. These scientists had targeted choleteryl ester transfer protein (CETP), an intermediary molecule that plays an important role in the balance of HDL and LDL. The vaccine they developed induces antibodies against CETP and ultimately increases HDL. But after the acquisition of AVANT by another company called Celldex, it is not clear if the scientists will proceed with the vaccine.

The Karolinska scientists, however, plan to go ahead with developing a vaccine against PC. They expect to be ready with it in two years, and clinical trials would take another two or three years, by which time there would be many other cardiovascular vaccines under development. Vaccines help to address a large number of people with the lowest possible risk. Within a decade, they could become the most important strategy against a large number of diseases, let alone cardiovascular disease.

Sources: The Telegraph (Kolkata, India)

Zemanta Pixie