Spermidine Levels in the Blood Considered a Potential Biomarker for Alzheimer’s Disease

One of the more important elements of slowing the progression of Alzheimer’s disease, if not the most significant, is identifying the preclinical stage of this type of Dementia. If the prospect of developing full-blown Alzheimer’s can be medically detected at the preclinical stage (before a person exhibits substantial symptoms), steps can be taken to slow the progression of this disease. 

Recently, this type of diagnosis has been undertaken through the extraction of cerebrospinal fluids. This process is notably more expensive than a blood draw. In addition, it is a far more significant strain on a patient’s body because it entails fluid extraction from an individual’s spinal cavity.

What Is Spermidine?

Biologically speaking, spermidine is classified as an aliphatic polyamine. Aliphatic polyamines are classified as a family of polycationic molecules derived from decarboxylation of the amino acid ornithine that classically comprises three molecules: 

  • Putrescine
  • Spermidine
  • Spermine

“In-cell polyamine homeostasis is tightly controlled at key steps of cell metabolism. Polyamines are involved in an array of cellular functions, from DNA stabilization and regulation of gene expression to ion channel function and cell proliferation.”

Simplifying all of this, spermidine is a molecule that can be found in all the cells in our bodies. Spermidine can be formed in the body from precursors. We are also able to absorb spermidine through food. Spermidine assists cells in eliminating cellular waste. This process biologically is called autophagy. It is assumed among researchers that spermidine uses autophagy to slow down the aging process at the cell level. 

Research Study on Spermidine as a Blood-Based Biomarker for Alzheimer’s Disease

In a recent study, an international team of researchers led by Professor Agnes Flöel of the University of Medicine Greifswald examined the role of spermidine in brain aging. The study was published in the journal Alzheimer’s & Dementia. This is the first study investigating the role of spermidine blood level values across the lifespan in a community-based cross-sectional sample of women and men. Six hundred fifty-nine healthy participants were involved as subjects in this research study.

Using magnetic resonance imaging or MRI, researchers discovered that elevated spermidine blood levels indicate advanced brain aging. This means that spermidine could play a role during the development of neurodegenerative diseases like Alzheimer’s disease.

Researchers utilized four MRI-based brain markers. The researchers demonstrated that elevated spermidine blood levels were associated with advanced brain aging. This was demonstrated by all four markers used by the researchers. Study participants were healthy and had no diagnosis of neurodegenerative diseases like Alzheimer’s.

“To better understand this well-known contrast, we wanted to investigate the relationship between spermidine blood levels and established MRI-based brain markers that show changes during brain aging and in Alzheimer’s disease in the general population,” explained Silke Wortha, Ph.D., first author of the research study.

“Our study shows that physiological spermidine blood levels do not reflect the beneficial health effects observed with higher dietary spermidine intake in animal models and human studies. Additionally, results show that spermidine blood levels could be a potential biomarker for preclinical Alzheimer’s disease. This is important since blood-based biomarkers for Alzheimer’s disease are less expensive and less of a strain on patients’ bodies compared to cerebrospinal fluid diagnostics, which entails the extraction of fluid from the spinal cavity,” says Professor Agnes Flöel, senior author of the study.

Beyond Diagnostic Testing: Diagnosing Alzheimer’s at an Early Stage

In the absence of the types of diagnostic tests referenced in this article, the typical manner in which Dementia, including Alzheimer’s, is detected is when an individual begins to exhibit some early symptoms of the disease. The early signs of Alzheimer’s are similar to those associated with other types of Dementia. At this juncture, Alzheimer’s disease is the most commonly diagnosed type of Dementia. These early signs of Alzheimer’s disease are:

  • Memory loss
  • Misplacing items
  • Forgetting the names of places and objects
  • Repeating themselves regularly, such as asking the same question several times
  • Becoming less flexible and more hesitant to try new things

The reality is that in some cases, a diagnosis of Alzheimer’s is not made until a person exhibits middle-stage signs of the disease:

  • Increasing confusion and disorientation
  • Obsessive, repetitive, or impulsive behavior
  • Delusions (believing untrue things)
  • Problems with speech or language (aphasia)
  • Disturbed sleep
  • Changes in mood, such as frequent mood swings, depression, and feeling increasingly anxious, frustrated, or agitated
  • Difficulty in performing spatial tasks, such as judging distances
  • Agnosia (loss of ability to identify certain objects with the senses)

Benefits of Early Diagnostic Testing

One of the most important benefits of early diagnostic testing is that you might be able to rule out an Alzheimer’s diagnosis. Memory lapses can be caused by other treatable medical conditions, provided they are properly diagnosed.

If a diagnosis of Alzheimer’s disease is made through diagnostic testing, some of the important benefits of having this information during the early stage of the disease include:

  • Optimize benefits of treatments and lifestyle changes that can delay the onset of more severe symptoms or reduce the severity of these symptoms
  • Allow more time to undertake thoughtful planning
  • Pursue goals and objectives before symptoms become more significant
  • Access valuable resources and services

In conclusion, while there is no cure for Alzheimer’s disease at this time, there are treatments and lifestyle changes that can slow the progression or delay the onset of severe symptoms. As mentioned previously, these treatments and lifestyle changes are most effective when implemented during the early stage of Alzheimer’s disease and other forms of Dementia. With diagnostic testing of the type suggested by the research study involving spermidine levels in the blood, the prospect exists for being able to make a preclinical diagnosis of Alzheimer’s at a juncture in time before a person begins to exhibit any notable symptoms of the disease.