Biomedical Scientist recently published ‘A preventative approach for Alzheimer’s’, which explores the first study evaluating the impact of obesity on Alzheimer’s blood biomarkers.
Guilherme Stahlberg reviews how products available from Oxford BioSystems may be useful in measuring these biomarkers.
Specific biomarker assays have increasingly become an area of interest for researchers studying neurodegenerative conditions such as Alzheimer’s, Parkinsons and Multiple sclerosis (MS). A recent study by Soheil Mohammadi et al (Alzheimer’s & Dementia: Diagnosis, Assessment & Disease Monitoring Vol 17, Issue 3, July-Sept 2025) utilised 1228 plasma samples from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) to investigate the link between obesity and Alzheimer’s disease. The study utilised commercial immunoassays for specific blood biomarkers including neurofilament light chain, glial fibrillary protein (GFAP) and p-tau217, as well as amyloid positron emission tomography (PET).
Obesity is regarded as a risk factor for Alzheimer’s disease but a conclusive link between Alzheimer’s disease biomarkers, PET trajectories and obesity has not previously been established.
Oxford BioSystems provides a range of in vitro diagnostic products relevant to neurodegeneration including several assays which can be used to measure the blood biomarkers identified in this study.
What blood biomarkers were studied?
Neurofilament Light Chain (NfL)
NfL is a structural protein in the neurons that provides stability and allows neurons to maintain their structure. When neurons are damaged, NfL is released into the blood and cerebrospinal fluid (CSF). High levels of NfL in the blood and CSF is an indicator of neuronal damage and is a useful biomarker for neurological diseases.
Tecan IBL provides NF-Light ELISA kits which allow for quantification of Nfl in both CSF and serum samples.
Glial fibrillary acidic protein (GFAP)
GFAP is the main protein in the intermediate filament network of astrocytes which are cells that perform many essential functions in the brain and are also an essential part of the blood-brain barrier. Astrocytes make up 20-40% of the cells in the brain.
GFAP is a highly specific brain protein which is not found outside of the central nervous system (CNS). It has been shown to be released into the blood very soon after traumatic brain injury (TBI), making it a suitable blood biomarker for neurodegenerative diseases, as well as TBI caused by trauma, disease, genetic disorders or chemical insult.
Oxford BioSystems is the UK distributor for BioVendor GFAP ELISA for the quantification of GFAP in CSF, serum or plasma samples.
pTau217
Tau protein is a protein found in the microtubules of neuron axons. Phosphorylation of tau is a normal process for proper function of microtubules. Hyperphosphorylation of tau however can lead to neurodegeneration and phosphorylated tau (p-tau) is a biomarker of interest in the study of Alzheimer’s disease. There are several forms of phosphorylated tau but p-tau217 is considered to be one of the most significant for early detection of Alzheimer’s disease.
Oxford Biosystems is the UK distributor for Tecan IBL p-tau217 ELISA kit, specifically designed to measure p-tau217 in human CSF samples.
Tecan IBL also provides ELISA kits for measuring p-tau231, for tau aggregates, a kit for non-phosphorylated tau and the new BD-tau luminescence immunoassay kit.
Beta amyloid
Amyloid plaques are extracellular deposits of amyloid beta protein. Amyloid-beta is a protein fragment that is snipped from an amyloid precursor protein (APP). In a healthy brain these protein fragments are broken down and eliminated. In Alzheimer's disease the fragments accumulate to form hard, insoluble plaques. The accumulation of amyloid plaques between nerve cells (neurons) in the brain is a well-documented feature of Alzheimer’s disease.
The study referred to in this article measured amyloid beta plaques using PET, which is both extremely expensive and comes with many limitations and side effects.
The Tecan IBL product range for Neurodegeneration biomarkers includes a comprehensive product portfolio around the APP-cascade for use with both serum and CSF samples.
What conclusions were made in the study?
The biomarkers investigated in the study were found at lower levels in plasma from patients with higher BMI values. Long term analysis however, found that obesity increased levels of p-tau217, p-tau217 ratio, NfL and amyloid PET over time.
While an increase in GFAP was not observed in this study, future research with modified methodology could mean that GFAP is still a biomarker of interest.
What does this mean for future studies?
The study provides an interesting perspective of the long-term effects of obesity on Alzheimer’s disease and demonstrates a clear advantage in using blood biomarkers to monitor and predict neurodegenerative diseases.
Obesity has been linked not only to Alzheimer’s but also to other neurodegenerative illnesses such as Parkinsons. Greater use of blood biomarkers in future studies could provide a deeper understanding of the link between obesity and specific neurodegeneration blood biomarkers.
The study also found many existing gaps in the way biomarker samples are studied and corrected, and further investigation clearly needs to be done to evaluate the effect of increased blood volume and decreased CSF volume in obese patients and the implication that this could have for biomarker tests.
Recently, new methods of tackling obesity such as GLP-1 agonists have also been an area of significant research and investment. The effectiveness of weight loss drugs in treating neurodegenerative diseases through the treatment of obesity is an area of important research. As GLP-1 agonists are a new area of study and many clinical trials are still ongoing, the need for effective blood biomarkers for testing neurodegeneration will increase.
How Oxford BioSystems can help you with your research
The assays mentioned in this article are not an exhaustive list of neurodegeneration tests provided by Oxford BioSystems. As this area becomes the subject of further research, there will be a greater need for novel methods of testing the link between neurodegenerative disease, obesity and blood biomarkers assays. A comprehensive list of relevant assays provided by Oxford BioSystems can be found on our Neurodegeneration webpage.
You can also download Tecan IBL’s Neurodegeneration Brochure for more information about their products, distributed to the UK and Ireland by Oxford BioSystems.
Get in touch with a member of our team to discover more.