Tag: cholesterol

Categories : Cardiovascular Disease Diet and NutritionTags :

Eggs are not the Cholesterol Menace They were Thought to be

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Many people hesitate to eat eggs amid concerns that they may raise cholesterol levels, with negative cardiovascular consequences. However, results from a prospective, controlled trial presented at the American College of Cardiology’s Annual Scientific Session show that over a four-month period cholesterol levels and other cardiovascular markers were similar among people who ate fortified eggs most days of the week compared with a non-egg eating control group.

A total of 140 patients with or at high risk for cardiovascular disease were enrolled in the PROSPERITY trial, which aimed to assess the effects of eating 12 or more fortified eggs a week versus a non-egg diet (consuming less than two eggs a week) on HDL- and LDL-cholesterol, as well as other key markers of cardiovascular health over a four-month study period.

“We know that cardiovascular disease is, to some extent, mediated through risk factors like high blood pressure, high cholesterol and increased BMI and diabetes. Dietary patterns and habits can have a notable influence on these and there’s been a lot of conflicting information about whether or not eggs are safe to eat, especially for people who have or are at risk for heart disease,” said Nina Nouhravesh, MD, a research fellow at the Duke Clinical Research Institute in Durham, North Carolina, and the study’s lead author. “This is a small study, but it gives us reassurance that eating fortified eggs is OK with regard to lipid effects over four months, even among a more high-risk population.”

Eggs are a common and relatively inexpensive source of protein and dietary cholesterol. Nouhravesh and her team wanted to look specifically at fortified eggs as they contain less saturated fat and additional vitamins and minerals, such as iodine, vitamin D, selenium, vitamin B2, 5 and 12, and omega-3 fatty acids.

For this study, patients were randomly assigned to eat 12 fortified eggs a week (cooked in whatever manner they chose) or to eat fewer than two eggs of any kind (fortified or not) per week.  All patients were 50 years of age or older (the average age was 66 years), half were female and 27% were Black. All patients had experienced one prior cardiovascular event or had two cardiovascular risk factors, such as high blood pressure, high cholesterol, increased BMI or diabetes. The co-primary endpoint was LDL and HDL cholesterol at four months. Secondary endpoints included lipid, cardiometabolic and inflammatory biomarkers and levels of vitamin and minerals. 

Patients had in-person clinic visits at the start of the study and visits at one and four months to take vital signs and have bloodwork done. Phone check-ins occurred at two and three months and patients in the fortified egg group were asked about their weekly egg consumption. Those with low adherence were provided additional education materials.

Results showed a -0.64mg/dL and a -3.14mg/dL reduction in HDL-cholesterol and LDL cholesterol, respectively, in the fortified egg group. While these differences weren’t statistically significant, the researchers said the differences suggest that eating 12 fortified eggs each week had no adverse effect on blood cholesterol. In terms of secondary endpoints, researchers observed a numerical reduction in total cholesterol, LDL particle number, another lipid biomarker called apoB, high-sensitivity troponin (a marker of heart damage), and insulin resistance scores in the fortified egg group, while vitamin B increased.

“While this is a neutral study, we did not observe adverse effects on biomarkers of cardiovascular health and there were signals of potential benefits of eating fortified eggs that warrant further investigation in larger studies as they are more hypothesis generating here,” Nouhravesh said, explaining that subgroup analyses revealed numerical increases in HDL cholesterol and reductions in LDL cholesterol in patients 65 years or older and those with diabetes in the fortified egg group compared with those eating fewer than two eggs.

So why have eggs gotten a bad rap? Some of the confusion stems from the fact that egg yolks contain cholesterol. Experts said a more important consideration, especially in the context of these findings, might be what people are eating alongside their eggs, such as buttered toast, bacon and other processed meats, which are not heart healthy choices. As always, Nouhravesh said it’s a good idea for people with heart disease to talk with their doctor about a heart healthy diet.

This single-centre study is limited by its small size and reliance on patients’ self-reporting of their egg consumption and other dietary patterns. It was also an unblinded study, which means patients knew what study group they were in, which can influence their health behaviours.

The study was funded by Eggland’s Best.

Source: American College of Cardiology

Categories : Cardiovascular Disease Diet and NutritionTags :

Cholesterol Discovery could Lead to New Therapies to Prevent Cardiovascular Disease

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Source: CC0

Researchers at the University of Leicester have discovered the mechanism by which cholesterol in the diet is absorbed into cells. This discovery, which has just been published in the journal Science opens up new opportunities for therapeutic intervention to control cholesterol uptake that could complement other therapies and potentially save lives.

The research, conducted with colleagues from the USA, China and Australia, has shown that two proteins (called Aster B and Aster C) play a key role in transporting cholesterol from the membrane of the cells lining our intestine to the internal compartment where it is modified prior to circulation.

Funding came from the Leducq Foundation which awarded $6 million to eight laboratories across the USA and Europe for collaborative research into how cholesterol is transported in our bodies.

University of Leicester researchers from the Institute of Structural and Chemical Biology, used their expertise to reveal how Ezetimibe, a cholesterol lowering drug, blocks the ability of Aster B and C to transport cholesterol.

Professor John Schwabe, Director of the Institute for Structural and Chemical Biology, said: “This breakthrough is the result of a long-lasting collaboration and forms part of an international effort to identify ways in which we can combat cardiovascular disease and stroke. A better understanding of important areas of cholesterol absorption and metabolism and, particularly, how cholesterol moves within cells and tissues is essential. This knowledge will allow us to design new drugs and therapies that target specific proteins involved in these pathways to combat most pressing public health problems such as heart attacks and stroke.

Professor Schwabe added: “If we can prevent some cholesterol from being absorbed into our cells, we may ultimately be able to prevent individuals from having high cholesterol and cut down their risks of heart attack and stroke and therefore potentially save lives.

“The Leducq team of experts have different expertise that is used to target the problem at different levels and following different approaches. In addition to target cholesterol absorption, we are trying to identify how cholesterol metabolism and transport affect cholesterol levels and atherosclerotic disease. Cholesterol transporters are essential to regulate blood cholesterol levels therefore we are testing small molecules that influence the function of these transporters in order to develop drugs that ultimately lower the risk for heart attack and stroke.”

Postdoctoral Researcher, Dr Beatriz Romartinez-Alonso, added: “This has been a great project to work on – discovering new science highly relevant to human health.”

Source: University of Leicester

Categories : Metabolic Disorders Neurodegenerative DiseasesTags :

Fluctuating Cholesterol and Triglyceride Levels Linked to Developing Dementia

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Older people who have fluctuating levels of total cholesterol and triglycerides may have a higher risk of Alzheimer’s disease and related dementias compared to people who have steady levels, according to new research published online in Neurology. Since the study is observational, it cannot establish a causative link.

“Prevention strategies for Alzheimer’s and related dementias are urgently needed,” said study author Suzette J. Bielinski, PhD, of the Mayo Clinic in Rochester, Minnesota. “Routine screenings for cholesterol and triglyceride levels are commonly done as part of standard medical care. Fluctuations in these results over time could potentially help us identify who is at greater risk for dementia, help us understand mechanisms for the development of dementia and ultimately determine whether levelling out these fluctuations could play a role in reducing dementia risk.”

Researchers used health care data to identify 11 571 people age 60 or older without a prior diagnosis of Alzheimer’s disease or dementia. They assessed total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL) and high-density lipoprotein cholesterol (HDL) for the participants on at least three different days in the five years before the start of the study. Then participants were assigned into five equal groups based on the degree of measurement fluctuation, from lowest to highest.

Participants were followed for an average of 13 years. During that time, 2473 of them developed Alzheimer’s disease or another form of dementia. After adjusting for confounding variables, researchers found for total cholesterol, participants in the highest fluctuation group had a 19% increased risk of dementia compared to those in the lowest group. Of the 2311 people in the highest group, 515 developed dementia compared to 483 of the 2311 people in the lowest group. For triglycerides, those in highest group had a 23% increased risk.

No link was found between dementia and variations in LDL and HDL, however.

“It remains unclear why and how fluctuating levels of cholesterol and triglycerides are related to the risk of Alzheimer’s disease,” said Bielinski. “Further studies looking at the changes over time for this relationship are needed in order to confirm our results and potentially consider preventative strategies.”

One study limitation was that researchers looked at Alzheimer’s disease and related dementias as a whole and did not differentiate between the types of dementia.

Source: American Academy of Neurology

Categories : Cardiovascular Disease GenderTags :

Atherosclerosis is a Greater Heart Attack Risk for Women

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Source: Wikimedia CC0

Postmenopausal women with atherosclerosis are at higher risk of heart attacks than men of similar age, according to research presented at EACVI 2023, a scientific congress of the European Society of Cardiology (ESC), and published in European Heart Journal – Cardiovascular Imaging. Researchers used imaging techniques to examine the arteries of nearly 25 000 patients and followed them for heart attacks and death.

“The study suggests that a given burden of atherosclerosis is riskier in postmenopausal women than it is in men of that age,” said study author Dr Sophie van Rosendael of Leiden University Medical Centre. “Since atherosclerotic plaque burden is emerging as a target to decide the intensity of therapy to prevent heart attacks, the findings may impact treatment. Our results indicate that after menopause, women may need a higher dose of statins or the addition of another lipid-lowering drug. More studies are needed to confirm these findings.”

While young women do have heart attacks, in general, women develop atherosclerosis (narrowing of arteries due to plaque buildup) later in life than men and have heart attacks at an older age than men, in part because of the protective effect of oestrogen. This study examined whether the prognostic importance of atherosclerotic plaques are the same for women and men at different ages as this could be important for selecting treatments to prevent heart attacks.

The study included 24 950 patients referred for coronary computed tomography angiography (CCTA) and enrolled in the CONFIRM registry, which was conducted in six countries in North America, Europe, and Asia. CCTA is used to obtain 3D images of the arteries in the heart.

Total atherosclerotic burden was rated using the Leiden CCTA score, which incorporates the following items for each coronary segment: plaque presence (yes/no), composition (calcified, noncalcified or mixed), location, and severity of narrowing, for a final value of 0 to 42. Patients were divided into three categories previously found to predict the risk myocardial infarction: low atherosclerotic burden (0 to 5), medium (6 to 20) and high (over 20). In addition, obstructive coronary artery disease was defined as 50% narrowing or more.

The primary outcome was the difference in Leiden CCTA score between women and men of similar age. The investigators also analysed sex differences in the rates of major adverse cardiovascular events (MACE), which included all-cause death and myocardial infarction, after adjusting for age and cardiovascular risk factors (hypertension, high cholesterol, diabetes, current smoking and family history of coronary artery disease).

A total of 11 678 women (average age 58.5 years) and 13 272 men (average age 55.6 years) were followed for 3.7 years. Regarding the primary outcome, the study showed an approximately 12 year delay in the onset of coronary atherosclerosis in women: the median Leiden CCTA risk score was above zero at age 64 to 68 years in women versus 52 to 56 years in men (p<0.001). In addition, the overall plaque burden as quantified by the Leiden CCTA score was significantly lower in women, who had more non-obstructive disease.

Dr. van Rosendael said: “The results confirm the previously reported delay in the start of atherosclerosis in women. We also found that women are more likely to have non-obstructive disease. It was formerly thought that only obstructive atherosclerosis caused myocardial infarction but we now know that non-obstructive disease is also risky.”
 
The burden of atherosclerosis was equally predictive of MACE in premenopausal women (aged under 55 years) and men of the same age group. However, in postmenopausal women (age 55 years and older), the risk of MACE was higher than men for a given score. In postmenopausal women, compared to those with a low burden, those with a medium and high burden had 2.21-fold and 6.11-fold higher risks of MACE. While in men aged 55 years and older, compared to those with a low burden, those with a medium and high burden had 1.57-fold and 2.25-fold greater risks of MACE.

Dr van Rosendael said: “In this study, the elevated risk for women versus men was especially observed in postmenopausal women with the highest Leiden CCTA score. This could be partly because the inner diameter of coronary arteries is smaller in women, meaning that the same amount of plaque could have a larger impact on blood flow. Our findings link the known acceleration of atherosclerosis development after menopause with a significant increase in relative risk for women compared to men, despite a similar burden of atherosclerotic disease. This may have implications for the intensity of medical treatment.”

Source: European Society of Cardiology

Categories : New Compounds and TreatmentsTags :

A New Drug Class Lowers Cholesterol by 70%

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Photo by Artem Podrez on Pexels

A new study using mouse models describes an orally administered small-molecule drug that reduces lowers cholesterol by 70% by preventing the degradation of low-density lipoprotein (LDL) receptors. Published in Cell Reports, the findings point to a previously unrecognised strategy for managing cholesterol – one which may also impact cancer treatments.

“Cholesterol lowering is one of the most important therapies we have to prolong life and protect people from heart disease, which is still the number one cause of morbidity and mortality in the Western world,” said senior author Jonathan S. Stamler, MD, professor at Case Western Reserve School of Medicine.

“Statins only lower cholesterol so far. This is a drug class that we think would represent a new way to lower cholesterol, a new way to hit PCSK9.”

Study Findings

Central to cholesterol regulation are LDL receptors, which sit at the surface of liver cells and remove cholesterol from the blood, thereby lowering serum levels. PCSK9 in the bloodstream controls the number of LDL receptors by marking them for degradation. Therefore, agents that inhibit PCSK9 increase the number of LDL receptors that remove cholesterol.

Nitric oxide is a molecule that is known to prevent heart attacks by dilating blood vessels. In the new study, Stamler and colleagues show that nitric oxide can also target and inhibit PCSK9, thus lowering cholesterol. They identify a small molecule drug that functions to increase nitric oxide inactivation of PCSK9. Mice treated with the drug display a 70% reduction in LDL cholesterol.

Beyond Cholesterol to Cancer

In addition to impacting the field of cholesterol metabolism, the findings may impact patients with cancer, as emerging evidence suggests targeting PCSK9 can improve the efficacy of cancer immunotherapies.

“PCSK9 not only targets LDL receptors for degradation, it also mediates the degradation of MHC 1 on lymphocytes, which is used for recognition of cancer cells” said Stamler. “PCSK9 is effectively preventing your lymphocytes from recognising cancer cells. So, if you inhibit PCSK9, you can boost the body’s cancer surveillance. There may be an opportunity one day to apply these new drugs to that need.”

Categories : Cardiovascular Disease Diet and NutritionTags :

An Egg a Day Keeps the Cardiologist Away

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Research published in eLife has shown how moderate egg consumption can increase the amount of heart-healthy metabolites in the blood. The findings suggest that eating up to one egg per day may help lower the risk of developing cardiovascular disease.

A rich source of dietary cholesterol, eggs also contain a variety of essential nutrients. Eggs have long had a bad rap when it comes to cardiovascular health, with conflicting evidence as to whether egg consumption is beneficial or harmful to heart health. A large study in China showed that those who ate one egg a day had a lower cardiovascular disease risk than those who ate eggs occasionally. To explore this, researchers carried out a population-based study exploring how egg consumption affects markers of cardiovascular health in the blood.

“Few studies have looked at the role that plasma cholesterol metabolism plays in the association between egg consumption and the risk of cardiovascular diseases, so we wanted to help address this gap,” explained first author Lang Pan, MSc at the Department of Epidemiology and Biostatistics, Peking University, Beijing, China.

Pan and the team selected 4778 participants from the China Kadoorie Biobank, 3401 of whom had a cardiovascular disease and 1377 did not. Measuring 225 metabolites in plasma samples taken from the participants’ blood, they identified 24 that were associated with self-reported levels of egg consumption.

Their analyses showed that individuals who ate a moderate amount of eggs had higher levels of a protein in their blood called apolipoprotein A1- a building-block of high-density lipoprotein (HDL). These individuals especially had more large, protective HDL molecules in their blood.

The researchers further identified 14 metabolites linked to heart disease, and participants who ate fewer eggs had lower levels of beneficial metabolites and higher levels of harmful ones in their blood, compared to regular egg eaters.

“Together, our results provide a potential explanation for how eating a moderate amount of eggs can help protect against heart disease,” says author Canqing Yu, Associate Professor at the Department of Epidemiology and Biostatistics, Peking University. “More studies are needed to verify the causal roles that lipid metabolites play in the association between egg consumption and the risk of cardiovascular disease.”

“This study may also have implications for Chinese national dietary guidelines,” adds senior author Liming Li, Boya Distinguished Professor at the Department of Epidemiology and Biostatistics, Peking University. “Current health guidelines in China suggest eating one egg a day, but data indicate that the average consumption is lower than this. Our work highlights the need for more strategies to encourage moderate egg consumption among the population, to help lower the overall risk of cardiovascular disease.”

Source: eLife

Categories : Cardiovascular Disease PaediatricsTags :

Cholesterol Screening Recommended for Children with Autism

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Physicians have recommended that children with autism spectrum disorder (ASD) receive screening for abnormally high or low cholesterol levels at least once during their childhood, since ASD is a risk factor for cardiovascular disease in both children and adults.

The recommendation stemmed from a recent study, published in Translational Psychiatry, that found reduced levels of high density lipoprotein cholesterol (HDL-C) in individuals from families with two or more children with ASD. Additionally, they found reduced or elevated levels of other lipids, apolipoprotein A1 (ApoA1) and apolipoprotein B (ApoB). Individuals with low HDL-C levels or ApoA1 levels had lower adaptive functioning than other individuals with ASD.

“This latest research is part of our ongoing work to understand some of the co-occurring conditions with ASD,” said Elaine Tierney, MD, a child and adolescent psychiatrist with Kennedy Krieger Institute. “Our work indicates that lipids are abnormal in many individuals with ASD. Our findings, in addition to studies that show an increase in heart disease in individuals with ASD, lead us to recommend that children with ASD be screened for abnormal total and HDL cholesterol levels. We hope our work underscores the importance of cholesterol screening and raises awareness for families in the ASD community.”

Previously, Dr Tierney and colleagues identified that Smith-Lemli-Opitz Syndrome (SLOS), a genetic condition of impaired cholesterol biosynthesis, is associated with autism. This led to a recommendation that all children with ASD be screened for SLOS if they exhibit some of its characteristics, such as slow growth, microcephaly, mental retardation and other birth defects, although the severity of this rare disease can vary.

Source: Kennedy Krieger Institute

Categories : Cardiovascular DiseaseTags :

New Easy Biomarker for Cardiovascular Risk

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A large study has shown that apolipoproteins apoB and apoA-1 together provide early and reliable cardiovascular risk information as well as levels of low-density lipoprotein (LDL) cholesterol. The researchers advocate introducing new guidelines for detecting cardiac risk and say the results, published in PLOS Medicine, may pave the way for early treatment, which could help lower morbidity and mortality rates.

Cardiovascular disease is the most common cause of death globally and includes a wide range of conditions, such as stroke and myocardial infarction with atherosclerosis in different organs of the body. In many cases the disease can be prevented and arrested with lifestyle changes and lipid-lowering treatments using statins and other methods.

The cardiac risk assessment usually uses reference values for the LDL cholesterol. Other types of fat particles can also be measured along with apolipoproteins, which transport cholesterol in the blood. International guidelines for cardiovascular disease recommend using apolipoprotein apoB, which transports LDL cholesterol, as an alternative risk marker for people with type 2 diabetes, overweight and very high levels of blood lipids.

Recent research has, however, indicated the importance of also factoring in the apolipoprotein apoA-1, which transports the protective and anti-inflammatory HDL cholesterol. Calculating the apoB/apoA-1 ratio gives a risk quotient reflecting the balance between the fat particles that expedite atherosclerosis and the “good” protective apoA-1 particles that arrest the process.

In this present study, the researchers have analysed the link between cardiovascular disease and apoB/apoA-1 values in more than 137 000 Swedish adults between the ages of 25 and 84. The individuals were followed for 30 years, during which time 22 000 suffered some form of cardiovascular event. The analysis methods are simple, inexpensive and safe, and do not require pre-test fasting, as is the case with LDL and non-HDL tests. Basing their study on a large database, the researchers linked the laboratory analyses to several clinical diagnosis registers.

“The results show that the higher the apoB/apoA-1 value, the greater the risk of myocardial infarction, stroke and need for coronary surgery,” says Göran Walldius, senior author and professor emeritus at the Institute of Environmental Medicine, Unit of Epidemiology, Karolinska Institutet. “The study also showed that the risk was amplified in the presence of low protective levels of apoA-1.”

Individuals with the highest apoB/apoA-1 values had a 70% higher risk of severe cardiovascular disease and almost triple the risk of non-fatal myocardial infarction compared with those with the lowest apoB/apoA-1 values. Individuals with the highest risk quotient were also more affected by severe cardiovascular diseases many years earlier than individuals with the lowest apoB/apoA-1 values.

The relationship was observed in both men and women and the elevated levels could be detected as early as 20 years before the onset of cardiovascular disease.

“Early preventive treatment and information about cardiovascular risk is, of course, important in enabling individuals to manage their risk situation,” Walldius says. “Early treatment can also reduce the cost burden on the public health services.”

Taken together, the results suggest that the apoB/apoA-1 ratio is a better marker for identifying at-risk individuals for cardiovascular disease compared to the apoB method alone.

“It should be possible to introduce cut-values for apoB, apoA-1 and the apoB/apoA-1 ratio into new guidelines as a complement to current guidance on the detection and treatment of dyslipidaemia,” said Walldius.

Source: Karolinska Institutet

Categories : CancerTags :

Link Between High Cholesterol and Breast Cancer Explained

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Source: National Cancer Institute

While chronically high cholesterol levels are linked to increased risks of breast cancer and worse outcomes in most cancers, the link had not been fully understood until now.

In a study published in Nature Communications, researchers identify the mechanisms at work, describing how breast cancer cells utilise cholesterol to develop stress tolerance, preventing them from dying as they migrate from the original tumour site.

“Most cancer cells die as they try to metastasise – it’s a very stressful process,” said senior author Donald P. McDonnell, Ph.D., professor in the departments of Pharmacology and Cancer Biology and Medicine at Duke University School of Medicine. “The few that don’t die have this ability to overcome the cell’s stress-induced death mechanism. We found that cholesterol was integral in fueling this ability.”

McDonnell and colleagues built on earlier research in their lab focusing on the link between high cholesterol and oestrogen-positive breast and gynaecological cancers. Those studies found that cancers fueled by the oestrogen hormone benefitted from derivatives of cholesterol that act like oestrogen, stoking cancer growth.

But a paradox emerged for estrogen-negative breast cancers. These cancers are not oestrogen dependent, but high cholesterol is still associated with worse disease, which indicates the possible effect of a different mechanism.

In the current study using cancer cell lines and mouse models, the Duke researchers found that migrating cancer cells gobble cholesterol in response to stress. Most die.

However, those that live emerge with a super-power that makes them able to withstand ferroptosis, a natural process in which cells succumb to stress. These stress-impervious cancer cells then proliferate and readily metastasise.

Other tumours beside ER-negative breast cancer cells use this process. including melanoma. And the mechanisms identified could be targeted by therapies.

“Unraveling this pathway has highlighted new approaches that may be useful for the treatment of advanced disease,” McDonnell said. “There are contemporary therapies under development that inhibit the pathway we’ve described. Importantly, these findings yet again highlight why lowering cholesterol — either using drugs or by dietary modification — is a good idea for better health.”

Source: Duke University

Categories : Neurodegenerative DiseasesTags :

Brain Cholesterol Production Linked to Alzehimer’s

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Amyloid plaques and neurons. Source: NIAH

Cholesterol manufactured in the brain appears to play a key role in the development of Alzheimer’s disease, new research indicates.

Scientists found that cholesterol produced by cells called astrocytes is required for controlling the production of amyloid beta, a sticky protein which forms the characteristic plaques in patients with Alzheimer’s. These plaques have been the target of efforts to remove or prevent them  in the hopes that this could treat or prevent Alzheimer’s.

The new findings offer important insights into how and why the plaques form and may explain why genes associated with cholesterol have been linked to increased risk for Alzheimer’s. The results also provide scientists with important direction as they seek to prevent Alzheimer’s.

“This study helps us to understand why genes linked to cholesterol are so important to the development of Alzheimer’s disease,” Heather Ferris, MD, PhD, Researcher, UVA’s Division of Endocrinology and Metabolism. “Our data point to the importance of focusing on the production of cholesterol in astrocytes and the transport to neurons as a way to reduce amyloid beta and prevent plaques from ever being formed.”

The work sheds light on the role of astrocytes in Alzheimer’s disease. Scientists have known that these common brain cells undergo dramatic changes in Alzheimer’s, but they have been uncertain if the cells were suffering from the disease or contributing to it. The new results suggest the latter.

The scientists found that astrocytes help drive the progression of Alzheimer’s by making and distributing cholesterol to brain cells called neurons. This cholesterol buildup increases amyloid beta production and, in turn, fuels plaque accumulation.

Normally, the buildup of amyloid beta is limited because cholesterol is kept quite low in neurons. But in Alzheimer’s, the neurons are no longer able to regulate amyloid beta, leading to plaque formation.
Blocking the astrocytes’ cholesterol manufacturing “robustly” decreased amyloid beta production in lab mice, the researchers reported. While it is presently unknown whether this could be applied in people to prevent plaque formation, the researchers believe that further research is likely to yield important insights that will benefit the battle against Alzheimer’s.

The fact that amyloid beta production is normally tightly controlled suggests an important role in brain cells, the researchers said. Doctors may therefore need to be cautious about blockage or removal of amyloid beta. Additional research into the discovery could shed light on how to prevent the over-production of amyloid beta as a strategy against Alzheimer’s, the researchers believe.

“If we can find strategies to prevent astrocytes from over-producing cholesterol, we might make a real impact on the development of Alzheimer’s disease,” Dr Ferris said. “Once people start having memory problems from Alzheimer’s disease, countless neurons have already died. We hope that targeting cholesterol can prevent that death from ever occurring in the first place.”

Source: University of Virginia Health System