The good cholesterol or high density lipoprotein (HDL) is essential for good health. However, the effects of HDL on the brain are not fully understood. Alzheimer’s disease is a disease that affects people’s ability to think and function in daily life. Researchers are still working to develop treatments and understand this disease. A recent study suggests that higher levels of small, high-density lipoproteins may reduce the risk of Alzheimer’s disease.
Alzheimer’s disease is a debilitating condition that primarily affects older people. People who have it can lose their memory and become unable to complete everyday tasks. The disease is currently incurable. Researchers are still trying to understand how the disease develops, how to prevent it, and how best to treat it. A recent study published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association sheds new light. Researchers have looked at the link between low HDL or “good” cholesterol in the cerebrospinal fluid and the risk of Alzheimer’s. The results suggest that higher levels of small HDL were associated with a lower risk of developing Alzheimer’s disease.
What is “good” cholesterol?
Cholesterol is a substance that the body needs. For example, the body uses cholesterol to make certain hormones, properly digest food, and form new cells. The body makes cholesterol, but humans can also get it from food sources.
Cholesterol occurs in the body in two main forms: low-density lipoproteins (LDL) and high-density lipoproteins (HDL). LDL can build up in the bloodstream and increase the risk of stroke and heart attack. It is therefore important that your LDL level is not too high.
The body’s HDL, or “good” cholesterol, helps bring cholesterol back to the liver so it can break it down. But HDL can affect other areas of health in ways that researchers don’t fully understand. For example, researchers are still trying to understand how HDL levels affect the brain. The study authors note that the HDL present in the brain is slightly different than the HDL present in the rest of the body.
What is Alzheimer’s?
Alzheimer’s disease is a disease that affects the brain and usually occurs in adults over the age of 60. It affects the nerves in the brain and is linked to the building of specific proteins in the brain. Eventually, neurons in the brain die and lose their ability to communicate with other brain cells.
Because of this damage, people with Alzheimer’s disease have problems with memory, language, and decision-making. It can be debilitating, and people with Alzheimer’s disease often slowly lose their ability to function independently.
Research into the causes of Alzheimer’s disease and the development of treatments continues.
Good cholesterol and Alzheimer’s disease
The study in question involved 180 participants aged 60 and over. Participants participated in the study through the Alzheimer’s Disease Research Center (ADRC) at the University of Southern California (USC) and the Huntington Memorial Research Institute’s (HMRI) Aging Program. The researchers assessed the participants’ cognitive functioning using various cognitive tests. They took samples of cerebrospinal fluid (CSF), the fluid that lines the brain and spinal cord, and plasma from the participants and isolated their DNA. The researchers searched the DNA for the APOE-ε4 gene, a potential risk factor for Alzheimer’s disease.
The researchers then examined the concentrations of small HDL particles in CSF. They found that higher levels of these small HDL particles were associated with better cognitive function in participants. They found that this result was the same even after accounting for the APOE ε4 gene, age, gender and educational level. The results of the study could lead to the development of new therapies for Alzheimer’s disease.
The authors conclude that “the discovery of lipid particles (LDL, HDL) in the blood has led to several advances in drug discovery for the treatment and prevention of cardiovascular disease. Here, for the first time, we measure HDL particles in cerebrospinal fluid as a surrogate for brain HDL and find that higher levels of small HDL correlate with better performance on cognitive measures. Now that we have this biomarker, our next step is to find out what drives the formation of these small HDL particles in the brain. These new discoveries could then lead to a new list of drugs in our fight against Alzheimer’s disease. »
Limitations of the study and further research
The study authors pointed out that their study had several limitations. First, it is difficult to identify which of these particles has the protective properties because there are many subtypes of small HDLs. They recognize that more research is needed to understand the interactions and differences between HDL in the brain and those in general circulation.
The researchers also acknowledge that the study results cannot be generalized and that the study does not show causality. Further research could examine whether HDL levels can predict the development of cognitive problems and whether an increase in HDL levels could help prevent Alzheimer’s disease. The researchers note that future studies could include more participants and have longer-term follow-ups.
This work is interesting and adds to the growing body of research studying different species in the cerebrospinal fluid. These findings on small, high-density lipoprotein particles are intriguing and could contribute to the development of biomarkers that can help predict how quickly Alzheimer’s disease will progress in humans. However, the sample size is quite small and further research is needed.
The small HDL particle hypothesis of Alzheimer’s disease
* Presse Santé strives to impart medical knowledge in a language accessible to all. In NO CASE can the information provided replace a medical consultation.
Like our content?
Receive our latest publications directly in your mailbox every day free of charge