The role of CSF biomarkers in the diagnostic work-up of mixed vascular-degenerative dementia

Metabolomics Deciphering the Potential Biomarkers of Hengqing I Prescription against Vascular Dementia

With the aging of population, vascular dementia (VaD) seriously threatens people's health and quality of life. It is of great significance to explore biomarkers of VaD from the perspective of metabolomics and traditional Chinese medicine (TCM). Therefore, VaD was divided into kidney deficiency and blood stasis syndrome (KDBS) and non-KDBS according to TCM. Then, some patients received the treatment of Hengqing I (HQI) prescription. The urine of six groups (VaD group, normal group, KDBS group, non-KDBS group, HQI group, and control group) was detected on LC-MS/MS. Multivariate statistical analysis showed that the metabolic profiles of the three comparisons were significantly different. The top analysis-ready molecules of downregulated histamine and upregulated biotin, methionine, pantothenic acid, SAH, histidine, and kaempferol may be the most related metabolites. These putative biomarkers play an important role in the regulation of key metabolic processes linked to VaD. Additionally, pathway analysis showed aminoacyl-tRNA biosynthesis, and amino acids metabolic pathways were highly correlated with the occurrence of VaD. In this present paper, vitamins, amino acids, and their derivatives were selected as the basis for VaD diagnosis and treatment monitoring, and the significance of TCM classification and Hengqing I prescription in the treatment of VaD was discussed.

Clinical features related to CSF level of amyloid Aβ42 and Aβ40 proteins in presence of lobar microbleeds

In presence of lobar microbleeds, the exact clinical features related to the level of Aβ42, Aβ40 and to the Aβ40/Aβ42 ratio in the cerebrospinal fluid (CSF) are poorly known. We analyzed in 28 consecutive patients with such lesions, whose clinical or additional magnetic resonance imaging features are related to these biomarkers. The results showed that the presence of absence of hypertension, the extent or the antero-posterior distribution of white matter hyperintensities, the presence or absence of vascular lesions in the deepest parts of the brain, and the presence of dementia are related to variations of Aβ42, Aβ40 or of the Aβ40/Aβ42 ratio in the cerebrospinal fluid.

Cerebrospinal Fluid Biomarkers for Early and Differential Alzheimer's Disease Diagnosis

An accurate and early diagnosis of Alzheimer’s disease (AD) is important to select optimal patient care and is critical in current clinical trials targeting core AD neuropathological features. The past decades, much progress has been made in the development and validation of cerebrospinal fluid (CSF) biomarkers for the biochemical diagnosis of AD, including standardization and harmonization of (pre-) analytical procedures. This has resulted in three core CSF biomarkers for AD diagnostics, namely the 42 amino acid long amyloid-beta peptide (Aβ_1-42), total tau protein (T-tau), and tau phosphorylated at threonine 181 (P-tau₁₈₁). These biomarkers have been incorporated into research diagnostic criteria for AD and have an added value in the (differential) diagnosis of AD and related disorders, including mixed pathologies, atypical presentations, and in case of ambiguous clinical dementia diagnoses. The implementation of the CSF Aβ_1-42/Aβ_1-40 ratio in the core biomarker panel will improve the biomarker analytical variability, and will also improve early and differential AD diagnosis through a more accurate reflection of pathology. Numerous biomarkers are being investigated for their added value to the core AD biomarkers, aiming at the AD core pathological features like the amyloid mismetabolism, tau pathology, or synaptic or neuronal degeneration. Others aim at non-AD neurodegenerative, vascular or inflammatory hallmarks. Biomarkers are essential for an accurate identification of preclinical AD in the context of clinical trials with potentially disease-modifying drugs. Therefore, a biomarker-based early diagnosis of AD offers great opportunities for preventive treatment development in the near future.

Cerebrospinal fluid τ protein in differential diagnosis of Alzheimer's disease and vascular dementia in Chinese population: a meta-analysis

BACKGROUND

To assess whether biomarker τ protein could differentiate between Alzheimer's disease (AD) and vascular dementia (VaD).

METHODS

We conducted a comprehensive search to identify studies on τ protein, patients with AD, and patients with VaD. Cerebrospinal fluid (CSF) τ protein levels were compared to discriminate among patients with AD, healthy controls, and patients with VaD by a meta-analysis.

RESULTS

Patients with AD exhibit significantly higher CSF τ protein levels than healthy controls or patients with VaD in the Chinese population.

CONCLUSION

Our findings suggested that CSF τ protein levels were found to be significantly associated with AD in the Chinese population. Measurement of τ protein could help in attenuating the strict distinction between AD and VaD.

Is Alzheimer's disease a homogeneous disease entity?

The epidemic proportions of dementia in old age are a cause of great concern for the medical profession and the society at large. It is customary to consider Alzheimer's disease (AD) as the most common cause of dementia, and vascular dementia (VaD) as being the second. This dichotomous view of a primary neurodegenerative disease as opposed to a disorder where extrinsic factors cause brain damage led to separate lines of research in these two entities. New biomarkers, particularly the introduction of modern neuroimaging and cerebrospinal fluid changes, have, in recent years, helped to identify anatomical and chemical changes of VaD and of AD. Nevertheless, there is a substantial difference between the two entities. While it is clear that VaD is a heterogeneous entity, AD is supposed to be a single disorder. Nobody attempts to use CADASIL as a template to develops treatment for sporadic VaD. On the other hand, early-onset AD is used to develop therapy for sporadic AD. This paper will discuss the problems relating to this false concept and its consequences.