Six Gut Markers May Identify Early Cognitive Decline

 Can your competent? doctor see the need for this testing and have available THE EXACT PROTOCOLS to prevent such decline?

Six Gut Markers May Identify Early Cognitive Decline

Blood tests detected metabolic shifts associated with nascent cognitive impairment

Key Takeaways

• Six diet- and gut-derived metabolites identified early cognitive impairment in older adults in a small study.
• The metabolite panel distinguished healthy controls from those with mild or subjective cognitive impairment.
• Findings suggest that metabolic disruptions may occur before clinical symptoms of dementia.

Six blood metabolites produced by or associated with gut microbiota identified early cognitive impairment in a small study.

The circulatory metabolites -- 5-hydroxyindole acetic acid, indole-3-propionic acid, choline, indoxyl sulfate, kynurenic acid, and kynurenine -- distinguished cognitively healthy older adults from those with mild cognitive impairment with an area under the curve (AUC) of 0.79, reported David Vauzour, PhD, of the University of East Anglia in Norwich, England, and co-authors.

The metabolites also separated healthy controls from people with subjective cognitive impairment with an AUC of 0.75, Vauzour and colleagues wrote in Gut Microbes. "This study shows that a small set of gut‑ and diet‑derived blood metabolites can reliably distinguish healthy aging from early cognitive decline, even at the very earliest stage," Vauzour told MedPage Today.

The panel of six metabolites reflects early metabolic disruption along the gut-brain axis, he noted. "These results highlight that metabolic alterations appear long before cognitive decline is clinically apparent, offering a non‑invasive and scalable approach for early risk identification," Vauzour said.

"Because circulating metabolites integrate both gut microbial activity and host physiology, they outperform microbiome‑only metrics and offer promising avenues for early detection, monitoring, and targeted intervention strategies," he added.

Recent research showed that the composition of the gut microbiome correlated with amyloid and tau markers in people with asymptomatic Alzheimer's disease. Growing evidence also suggests that changes to gut bacteria may be linked to dementia risk, noted Sheona Scales, PhD, of Alzheimer's Research UK, which supported the study."While current blood tests for Alzheimer's work by detecting levels of specific proteins linked with the disease, this research may offer a new avenue for future blood test development," Scales wrote on the U.K. Science Media Centre website.

"This study can't say whether people with early memory and thinking problems will go on to develop dementia, but it identifies an interesting area for further research," she pointed out. "Given the study involved a relatively small group of people, larger and longer-term studies are needed to build on these findings and understand whether this type of test could be used alongside existing ones."

Vauzour and co-authors studied 150 older adults: 50 cognitively healthy controls, 50 participants with subjective cognitive impairment, and 50 with objectively measured mild cognitive impairment.

Groups were matched on age, sex, and body mass index. The mean age across groups was 65.5 years and 54% were women. Blood and fecal sample data came from baseline measurements of two previously conducted clinical studies.

Participants were excluded if they had a history of significant neurologic, psychiatric, gastrointestinal, or metabolic disorders; chronic fatigue syndrome; or gallbladder abnormalities. Additional exclusion criteria included current or recent smoking, alcohol or drug dependency, and clinically significant depression or anxiety. Individuals were ineligible if they were taking antidepressants, antipsychotics, anticoagulants, or any medications affecting gastrointestinal function.

Mass spectrometry platforms analyzed 33 metabolites in serum -- 13 tryptophan-related compounds, 15 bile acid compounds, three trimethylamine N-oxide-related metabolites, and two cresol metabolites. Microbiome analysis using 16S rRNA amplicon sequencing was used to detect bacterial taxa associated with metabolic changes.

The researchers used multiple linear regression and machine learning techniques to identify a metabolite panel capable of classifying early cognitive decline. Of the six metabolites in the panel, all except choline were products of tryptophan metabolism.

"The work underscores tryptophan metabolism as a key pathway disrupted early in cognitive decline, with protective metabolites decreasing and inflammatory or toxic metabolites increasing," Vauzour said. "The observation that biological changes arise at the subjective cognitive impairment stage further supports the need to shift prevention efforts earlier in the disease trajectory."While the study adjusted for key covariates, metabolome profiles can be influenced by a plethora of environmental and biological factors, the researchers acknowledged. Metabolite changes may reflect physiological states associated with systemic inflammation, for example. "Thus, although our findings suggest relationships between the variables, we cannot infer causal relationships from this analysis alone," they wrote.

Future work should validate these metabolite signatures in larger, independent cohorts and across more diverse populations, Vauzour suggested.

"Longitudinal studies are needed to determine whether these metabolic changes can predict conversion from subjective cognitive impairment to objective cognitive impairment, and eventually, dementia," he stated. "Mechanistic studies, including microbiome manipulation or dietary interventions, could help clarify causal pathways and support the development of personalized, metabolite‑guided prevention strategies."

Judy George covers neurology and neuroscience news for MedPage Today, writing about brain aging, Alzheimer’s, dementia, MS, rare diseases, epilepsy, autism, headache, stroke, Parkinson’s, ALS, concussion, CTE, sleep, pain, and more. Connect:

Disclosures

The microbiota analysis in this study was supported by an Alzheimer's Research UK Small Pump Priming Grant.

Vauzour and co-authors reported no competing interests.

Scales had no disclosures.

Primary Source

Gut Microbes

Source Reference: Connell E, et al "Circulatory dietary and gut-derived metabolites predict early cognitive decline" Gut Microbes 2026; DOI: 10.1080/19490976.2026.2649487.

Changes of Metabolites in Acute Ischemic Stroke and Its Subtypes

 I got absolutely nothing out of this. Did your doctor?

Changes of Metabolites in Acute Ischemic Stroke and Its Subtypes

Xin Wang^1,2, Luyang Zhang^1,2, Wenxian Sun^1,2, Lu-lu Pei^1,2, Mengke Tian^1,2, Jing Liang^1,2, Xinjing Liu^1,2, Rui Zhang^1,2, Hui Fang^1,2, Jun Wu^1,2, Shilei Sun^1,2, Yuming Xu^1,2*, Jian-Sheng Kang^1* and Bo Song^1,2*

• ¹Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
• ²Henan Key Laboratory of Cerebrovascular Diseases, Zhengzhou, China

Existing techniques have many limitations in the diagnosis and classification of ischemic stroke (IS). Considering this, we used metabolomics to screen for potential biomarkers of IS and its subtypes and to explore the underlying related pathophysiological mechanisms. Serum samples from 99 patients with acute ischemic stroke (AIS) [the AIS subtypes included 49 patients with large artery atherosclerosis (LAA) and 50 patients with small artery occlusion (SAO)] and 50 matched healthy controls (HCs) were analyzed by non-targeted metabolomics based on liquid chromatography–mass spectrometry. A multivariate statistical analysis was performed to identify potential biomarkers. There were 18 significantly different metabolites, such as oleic acid, linoleic acid, arachidonic acid, L-glutamine, L-arginine, and L-proline, between patients with AIS and HCs. These different metabolites are closely related to many metabolic pathways, such as fatty acid metabolism and amino acid metabolism. There were also differences in metabolic profiling between the LAA and SAO groups. There were eight different metabolites, including L-pipecolic acid, 1-Methylhistidine, PE, LysoPE, and LysoPC, which affected glycerophospholipid metabolism, glycosylphosphatidylinositol-anchor biosynthesis, histidine metabolism, and lysine degradation. Our study effectively identified the metabolic profiles of IS and its subtypes. The different metabolites between LAA and SAO may be potential biomarkers in the context of clinical diagnosis. These results highlight the potential of metabolomics to reveal new pathways for IS subtypes and provide a new avenue to explore the pathophysiological mechanisms underlying IS and its subtypes.

Introduction

Stroke is one of the main causes of human death and disability (Wang et al., 2014) and is associated with a high rate of disability and recurrence. According to population-based studies (Benjamin et al., 2017), ischemic stroke (IS) accounts for more than 80% of all strokes. According to its etiology and imaging, IS can be categorized into five subtypes (Adams et al., 1993; Chen et al., 2012), including large artery atherosclerosis (LAA), small artery occlusion (SAO), cardioembolism, stroke of other determined cause, and stroke of undetermined cause. The classification of IS can help with the early treatment and prevention of long-term recurrence in patients (Montaner et al., 2008). However, the diagnosis and classification of IS mainly rely on neuroimaging techniques, which are scarce, expensive, and time-consuming (Latchaw et al., 2009). Therefore, new biomarkers for the rapid and accurate prediction, diagnosis, and classification of IS might play a positive role in clarifying the pathophysiological mechanism of IS and promoting the secondary prevention and management of patients with IS.

It is difficult to release macromolecules from the brain into the blood due to the presence of the blood–brain barrier (Jickling and Sharp, 2015). Some conventional detection methods make it difficult to detect specific sensitive different metabolites in patients with IS. However, with the development of the emerging science of metabolomics, it may be possible to identify specific small molecular biomarkers in patients with IS and determine the underlying etiology. Metabolomics is an effective method to reveal biomolecules’ phenotypes. This method enables the identification of changes in small molecular metabolites in various diseases, which can greatly help in understanding and diagnosing diseases. Many studies using metabolomics have revealed the differences in metabolites between patients with acute ischemic stroke (AIS) and healthy controls (HCs) (Jung et al., 2011; Kimberly et al., 2013). To date, few studies have explored the differences in metabolites between the LAA and SAO subtypes of IS. In this study, non-targeted metabolites based on liquid chromatography–mass spectrometry (LC–MS) were used to study the different metabolites between patients with AIS and the HCs and between patients with the LAA and SAO subtypes of IS. The proposed method offers important advantages over traditional alternatives, ensuring that it is feasible to screen potential biomarkers and further explore the relevant underlying pathophysiological mechanisms.

 

Omega-3 fatty acids could promote clearance of metabolites in the brain, research shows

Would this help in the aftermath of a stroke? I bet no followup will ever occur. Don't try this on your own, you know how dangerous fish oil is if your doctor didn't prescribe it.

Omega-3 fatty acids could promote clearance of metabolites in the brain, research shows

New research published online in The FASEB Journal suggests that omega-3 polyunsaturated fatty acids, which are found in fish oil, could improve the function of the glymphatic system, which facilitates the clearance of waste from the brain, and promote the clearance of metabolites including amyloid-β peptides, a primary culprit in Alzheimer's disease.
To make this discovery, scientists first used transgenic fat-1 mice, which express high endogenous omega-3 polyunsaturated fatty acids (PUFAs) in the brain, to investigate the effect of omega-3 PUFAs on the clearance function of the glymphatic system. Compared to the wild-type mice, the fat-1 mice with enriched endogenous omega-3 PUFAs significantly promote the clearance function of the lymphatic system, including the Aβ clearance from the brain. Wild-type mice were supplemented with fish oil, which contains high concentrations of omega-3 PUFAs, and found that fish oil-supplemented mice also improved the clearance function of the glymphatic system compared to the control mice without fish oil supplementation. Omega-3 PUFAs help maintain the brain homeostasis, which may provide benefits in a number of neurological diseases, such as Alzheimer's disease, traumatic brain injury, and sleep impairment, among others.
"These now-famous fatty acids have been the subject of major studies both in academia and industry. Just when we thought we had heard everything, here is something new, and it is provocative indeed," said Thoru Pederson, Ph.D., Editor-in-Chief of The FASEB Journal. "This study should not turn attention away from the roles of these substances in maintaining vascular health, but neither should they restrict our view. The brain is an extremely vascularized organ, while we might also bear in mind that omega-3 fatty acids may impact neurons, glia, and astrocytes themselves."

Source:

Federation of American Societies for Experimental Biology