Tryptophan Metabolism, Inflammation, and Oxidative Stress in Patients with Neurovascular Disease

Tryptophan metabolism and ischemic stroke: An intricate balance

Ischemic stroke, which is characterized by hypoxia and ischemia, triggers a cascade of injury responses, including neurotoxicity, inflammation, oxidative stress, disruption of the blood-brain barrier, and neuronal death. In this context, tryptophan metabolites and enzymes, which are synthesized through the kynurenine and 5-hydroxytryptamine pathways, play dual roles. The delicate balance between neurotoxic and neuroprotective substances is a crucial factor influencing the progression of ischemic stroke. Neuroprotective metabolites, such as kynurenic acid, exert their effects through various mechanisms, including competitive blockade of N-methyl-D-aspartate receptors, modulation of α7 nicotinic acetylcholine receptors, and scavenging of reactive oxygen species. In contrast, neurotoxic substances such as quinolinic acid can hinder the development of vascular glucose transporter proteins, induce neurotoxicity mediated by reactive oxygen species, and disrupt mitochondrial function. Additionally, the enzymes involved in tryptophan metabolism play major roles in these processes. Indoleamine 2,3-dioxygenase in the kynurenine pathway and tryptophan hydroxylase in the 5-hydroxytryptamine pathway influence neuroinflammation and brain homeostasis. Consequently, the metabolites generated through tryptophan metabolism have substantial effects on the development and progression of ischemic stroke. Stroke treatment aims to restore the balance of various metabolite levels; however, precise regulation of tryptophan metabolism within the central nervous system remains a major challenge for the treatment of ischemic stroke. Therefore, this review aimed to elucidate the complex interactions between tryptophan metabolites and enzymes in ischemic stroke and develop targeted therapies that can restore the delicate balance between neurotoxicity and neuroprotection.

Indole metabolism and its role in diabetic macrovascular and microvascular complications

Tryptophan (Trp), an essential amino acid obtained through dietary sources, plays a crucial role in various physiological processes. The metabolism of Trp branches into three principal pathways: the serotonin pathway, the kynurenine pathway, and the indole pathway. The kynurenine and serotonin pathways are host pathways while the indole pathway is solely the result of bacterial metabolism. Trp metabolites extend their influence beyond protein biosynthesis to affect a spectrum of pathophysiological mechanisms including, but not limited to, neuronal function, immune modulation, inflammatory responses, oxidative stress regulation, and maintenance of intestinal health. This review focuses on indole derivatives and their impact on vascular health. Trp-containing dipeptides are highlighted as a targeted nutraceutical approach to modulate Trp metabolism, enhance beneficial metabolite production, and mitigate risk factors for vascular diseases. The importance of optimizing Trp intake and dietary strategies to harness the benefits of Trp-derived metabolites for vascular health is underscored, bringing to light the need for further research to refine these therapeutic approaches.

Elevated initial blood kynurenine is associated with increased odds of post-stroke infection: Kynurenine and post-stroke infection

OBJECTIVE

Post-stroke infection is a leading cause of acute ischemic stroke mortality. Tryptophan metabolites can modulate the immune response. This study assesses the association between tryptophan metabolism and post-stroke infection.

METHODS

Whole blood from the University of Colorado Emergency Medicine Specimen Bank of acute ischemic stroke patients was collected within 72 hours of last known well. Mass spectrometry determined concentrations of tryptophan metabolites. Multivariate logistic regression modeled the association between post-stroke infection within 30 days and metabolite concentrations, controlling for age, sex, NIH stroke scale score, time to sample collection, smoking status, dysphagia, history of chronic kidney or end stage renal disease, and history of diabetes mellitus.

RESULTS

Of 73 subjects, 21 (28.8 %) developed a post-stroke infection. Those with or without a post-stroke infection had similar concentrations of tryptophan, kynurenic acid and quinolinic acid. Those who developed a post-stroke infection had higher mean concentrations of kynurenine (2.3μM, standard deviation 1.1μM) compared to those who did not develop a post-stroke infection (1.6μM , standard deviation 0.6μM, p = 0.01). The adjusted odds ratio of a post-stroke infection within 30 days was 3.94 (95 % Confidence Interval 1.40 - 11.11) for every 1μM increase in kynurenine concentration.

CONCLUSIONS

Increasing circulating kynurenine within 72 hours of ischemic stroke onset is associated with increased odds of developing a post-stroke infection within 30 days of emergency department admission. Understanding the causal mechanism of kynurenine promoting post-stroke infection may yield targeted therapeutics that reduce the morbidity and mortality of ischemic stroke.

3-HKA Promotes Vascular Remodeling After Stroke by Modulating the Activation of A1/A2 Reactive Astrocytes

Ischemic stroke is the most common cerebrovascular disease and the leading cause of permanent disability worldwide. Recent studies have shown that stroke development and prognosis are closely related to abnormal tryptophan metabolism. Here, significant downregulation of 3-hydroxy-kynurenamine (3-HKA) in stroke patients and animal models is identified. Supplementation with 3-HKA improved long-term neurological recovery, reduced infarct volume, and increased ipsilateral cerebral blood flow after distal middle cerebral artery occlusion (MCAO). 3-HKA promoted angiogenesis, functional blood vessel formation, and blood-brain barrier (BBB) repair. Moreover, 3-HKA inhibited A1-like (neurotoxic) astrocyte activation but promoted A2-like (neuroprotective) astrocyte polarization. Proteomic analysis revealed that 3-HKA inhibited AIM2 inflammasome activation after stroke, and co-labeling studies indicated that AIM2 expression typically increased in astrocytes at 7 and 14 days after stroke. Consistently, in co-cultures of primary mouse brain microvascular endothelial cells and astrocytes, 3-HKA promoted angiogenesis after oxygen-glucose deprivation (OGD). AIM2 overexpression in astrocytes abrogated 3-HKA-driven vascular remodeling in vitro and in vivo, suggesting that 3-HKA may regulate astrocyte-mediated vascular remodeling by impeding AIM2 inflammasome activation. In conclusion, 3-HKA may promote post-stroke vascular remodeling by regulating A1/A2 astrocyte activation, thereby improving long-term neurological recovery, suggesting that supplementation with 3-HKA may be an efficient therapy for stroke.

Sex Differences in Tryptophan Metabolism via the Kynurenine Pathway in Acute Ischemic Stroke

PURPOSE

Females are at increased lifetime risk of stroke and experience worse outcomes compared with males. Tryptophan metabolism through the kynurenine pathway, resulting in decreased tryptophan concentrations, is associated with poor outcomes (larger infarct volume, higher National Institutes of Health Stroke Scale [NIHSS] score, and increased early mortality). This metabolic pathway activity varies by sex in healthy adults. However, evaluation of potential sex differences in tryptophan metabolism after an acute ischemic stroke (AIS) is lacking and could contribute to the disparate outcomes by sex. This study characterized sex differences in tryptophan metabolism via the kynurenine pathway in patients with AIS.

METHODS

Whole blood from patients with AIS enrolled in the University of Colorado Health Emergency Medicine Specimen Bank was analyzed using high-throughput mass spectrometry-based metabolomics at the time of arrival to the emergency department and at 12, 24, and 48 hours thereafter. Descriptive statistics characterized the cohort and metabolite levels. Potential sex differences in tryptophan metabolites at individual time points and their change over time were estimated using linear regression models to control for known factors influencing metabolite levels, initial NIHSS score, therapeutic interventions, and time to last known well (or symptom onset). A multivariable linear regression model examined the interaction effect between sex and metabolite level (at 12 hours after admission) on 24-hour NIHSS score while controlling for initial metabolite level, initial NIHSS score, time to last known well, factors influencing metabolite level, and factors influencing neurologic outcomes.

FINDINGS

After adjusting for covariates, females with AIS had significantly lower levels of tryptophan at 12 hours after admission compared with males (point estimate, -5.80; P = 0.03). Females and males neither differ in levels of tryptophan, kynurenine, quinolinic acid, or kynurenic acid at any other time point nor did they differ in change in metabolite concentration over time. Only increased quinolinic acid levels across both sexes at 12 hours after admission were associated with increased 24-hour NIHSS scores (point estimate, 0.49; P = 0.0002).

IMPLICATIONS

Overall, females and males have similar levels and changes in tryptophan and kynurenine pathway metabolites after an AIS. However, females have lower levels of tryptophan early after a stroke. Increased quinolinic acid levels across both sexes were associated with worsening neurologic function as measured by an NIHSS score. Future evaluation of alternative metabolic pathways downstream of tryptophan is needed to explain differences in tryptophan levels but similar levels of downstream kynurenine metabolites in females and males with AIS.

Ionic liquid-based yellow-emitting carbon dots for fluorescence-smartphone dual-mode detection of vitamin B6 in milk

The determination of vitamin B6 (VB6) in food is of great significance due to its vital role in maintaining health and its necessity for ingestion through dietary sources. Therefore, based on ionic liquid-based yellow-emitting carbon dots (Y-CDs), a novel fluorescence-smartphone dual-mode method was first developed. The present method was applied to the detection of VB6 in milk. In the fluorescence method, the formation of complexes between VB6 and Y-CDs results in a significant decrease of the fluorescence intensity of Y-CDs. VB6 in milk samples was successfully determined according to this method, which exhibited a low detection limit (5 × 10-5 mg/mL) and excellent recoveries (98.80%-103.80%), demonstrating its feasibility in real sample analysis. In addition, the smartphone-based analysis method was established by researching the correlation between different VB6 concentrations and the (R + B) values of Y-CDs. When this method was applied, the detection process of VB6 was simplified. By combining the two methods, the possibility of incorrect analysis results can be effectively reduced, and the reliability of detection results can be improved through cross-validation of the two methods. Compared with traditional chromatography and electrochemical methods, the dual-mode method was more rapid, convenient, accurate, and suitable for the detection of VB6.

Redefining Roles: A Paradigm Shift in Tryptophan-Kynurenine Metabolism for Innovative Clinical Applications

The tryptophan-kynurenine (KYN) pathway has long been recognized for its essential role in generating metabolites that influence various physiological processes. Traditionally, these metabolites have been categorized into distinct, often opposing groups, such as pro-oxidant versus antioxidant, excitotoxic/neurotoxic versus neuroprotective. This dichotomous framework has shaped much of the research on conditions like neurodegenerative and neuropsychiatric disorders, as well as cancer, where metabolic imbalances are a key feature. The effects are significantly influenced by various factors, including the concentration of metabolites and the particular cellular milieu in which they are generated. A molecule that acts as neuroprotective at low concentrations may exhibit neurotoxic effects at elevated levels. The oxidative equilibrium of the surrounding environment can alter the function of KYN from an antioxidant to a pro-oxidant. This narrative review offers a comprehensive examination and analysis of the contemporary understanding of KYN metabolites, emphasizing their multifaceted biological functions and their relevance in numerous physiological and pathological processes. This underscores the pressing necessity for a paradigm shift in the comprehension of KYN metabolism. Understanding the context-dependent roles of KYN metabolites is vital for novel therapies in conditions like Alzheimer's disease, multiple sclerosis, and cancer. Comprehensive pathway modulation, including balancing inflammatory signals and enzyme regulation, offers promising avenues for targeted, effective treatments.

MCC950 as a promising candidate for blocking NLRP3 inflammasome activation: A review of preclinical research and future directions

The NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome is a key component of the innate immune system that triggers inflammation and pyroptosis and contributes to the development of several diseases. Therefore, blocking the activation of the NLRP3 inflammasome has therapeutic potential for the treatment of these diseases. MCC950, a selective small molecule inhibitor, has emerged as a promising candidate for blocking NLRP3 inflammasome activation. Ongoing research is focused on elucidating the specific targets of MCC950 as well as assessfing its metabolism and safety profile. This review discusses the diseases that have been studied in relation to MCC950, with a focus on stroke, Alzheimer's disease, liver injury, atherosclerosis, diabetes mellitus, and sepsis, using bibliometric analysis. It then summarizes the potential pharmacological targets of MCC950 and discusses its toxicity. Furthermore, it traces the progression from preclinical to clinical research for the treatment of these diseases. Overall, this review provides a solid foundation for the clinical therapeutic potential of MCC950 and offers insights for future research and therapeutic approaches.

A rapid and reliable targeted LC-MS/MS method for quantitative analysis of the Tryptophan-NAD metabolic network disturbances in tissues and blood of sleep deprivation mice

BACKGROUND

TRY-NAD metabolic network includes TRY (tryptophan), 5-HT (5-hydroxytryptamine), KYN (kynurenine), and NAD (nicotinamide adenine dinucleotide) pathway, which plays a significant role in neurological diseases and ageing. It is important to monitor these metabolites for studying the pathological anatomy of disease and treatment of responses evaluation. Although previous studies have reported quantitative methods for several metabolites in the network, the bottlenecks of simultaneously quantifying the whole metabolic network are their similar structures, diverse physico-chemical properties, and instability. Standardized protocols for the whole metabolic network are still missing, which hinders the in-depth study of TRY-NAD metabolic network in laboratory research and clinical screening.

RESULTS

We developed a LC-MS/MS method for quantifying 28 metabolites in the TRY-NAD network simultaneously. Optimization was done for the mass spectral parameters, chromatographic conditions and sample pretreatment process. The developed method was fully validated in terms of standard curves, sensitivity, carryover, recovery, matrix effect, accuracy, precision, and stability. The pretreatment of 30 samples only takes 90 min, and the LC-MS/MS running time of one sample is only 13 min. With this method, we bring to light the chaos of global TRY-NAD metabolic network in sleep deprivation mice for the first time, including serum, clotted blood cells, hippocampus, cerebral cortex, and liver. NAD pathway levels in brain and blood decreased, whereas the opposite happened in the liver. The 5-HT pathway decreased and the concentration of KYN increased significantly in the brain. The concentration of many metabolites in KYN pathway (NAD+ de novo synthesis pathway) increased in the liver.

SIGNIFICANCE

This method is the first time to determine the metabolites of KYN, 5-HT and NAD pathway at the same time, and it is found that TRY-NAD metabolic network will be disordered after sleep deprivation. This work clarifies the importance of the pH of the extraction solution, the time and temperature control in pretreatment in standardized protocols building, and overcoming the problems of inconsistent sample pretreatment, separation, matrix effect interference and potential metabolite degradation. This method exhibits great prospects in providing more information on metabolic disturbances caused by sleep deprivation as well as neurological diseases and ageing.

Circular RNA SCMH1 suppresses KMO expression to inhibit mitophagy and promote functional recovery following stroke

Rationale: Metabolic dysfunction is one of the key pathological events after ischemic stroke. Disruption of cerebral blood flow impairs oxygen and energy substrate delivery, leading to mitochondrial oxidative phosphorylation dysfunction and cellular bioenergetic stress. Investigating the effects of circSCMH1, a brain repair-related circular RNA, on metabolism may identify novel therapeutic targets for stroke treatment. Methods: CircSCMH1 was encapsulated into brain-targeting extracellular vesicles (EVs) mediated by rabies virus glycoprotein (RVG). Using a mouse model of photothrombotic (PT) stroke, we employed metabolomics and transcriptomics, combined with western blotting and behavioral experiments, to identify the metabolic targets regulated in RVG-circSCMH1-EV-treated mice. Additionally, immunofluorescence staining, chromatin immunoprecipitation (ChIP), pull-down, and western blotting were utilized to elucidate the underlying mechanisms. Results: The targeted delivery of circSCMH1 via RVG-EVs was found to promote post-stroke brain repair by enhancing mitochondrial fusion and inhibiting mitophagy through suppression of kynurenine 3-monooxygenase (KMO) expression. Mechanistically, circSCMH1 exerted its inhibitory effect on KMO expression by binding to the transcription activator STAT5B, thereby impeding its nuclear translocation. Conclusions: Our study reveals a novel mechanism by which circSCMH1 downregulates KMO expression, thereby enhancing mitochondrial fusion and inhibiting mitophagy, ultimately facilitating post-stroke brain repair. These findings shed new light on the role of circSCMH1 in promoting stroke recovery and underscore its potential as a therapeutic target for the treatment of ischemic stroke.

Ameliorative effect of diclofenac in rotenone corneal kindling model of drug-resistant epilepsy: Edge of dual COX and KMO inhibition

Epilepsy affects millions of people worldwide, about one-third patients with epilepsy exhibits resistance to available antiseizures medications, known as drug-resistant epilepsy (DRE). Mitochondrial dysfunction has been implicated as a hallmark in drug-resistant epilepsy via activation of microglial kynurenine 3-monooxygenase (KMO) and cyclooxygenase (COX) enzymes, leading to neuroinflammation and oxidative stress. Diclofenac, an equipotent non selective cyclooxygenase inhibitor, has inhibitory action on KMO enzyme and has also shown anti-inflammatory and antioxidant properties in animal models of epilepsy. These properties make it a suitable candidate for amelioration of DRE. However, its potential in drug-resistant epilepsy remained unexplored till date. In this study, dose dependent effect of diclofenac (5 mg/kg, 10 mg/kg, 20 mg/kg) has been explored in rotenone corneal kindling model of mitochondrial DRE. The results of our study revealed the induction of drug resistance to antiseizure medications and induced kynurenine 3-monooxygenase activity in rotenone corneal kindled epileptic mice in comparison to naive mice. Treatment of rotenone corneal kindled epileptic mice with diclofenac resulted in a significant decrease in drug resistance to antiseizure medications as evident by a reduction in seizure score in the treatment groups as compared to control group, in post-treatment resistance validation. The kynurenine 3-monooxygenase inhibitory activity (as evidenced by decreased levels of neurotoxic quinolinic acid) and the antioxidant effect (as evident by significantly reduced oxidative stress) in the diclofenac treated groups, emerged as a major contributor for its ameliorative action. Findings of this study suggests, diclofenac can be used as an adjunct therapy in amelioration of drug-resistant epilepsy.

The role of amino acid metabolism alterations in acute ischemic stroke: From mechanism to application

Acute ischemic stroke (AIS) is the most prevalent type of stroke, and due to its high incidence, disability rate, and mortality rate, it imposes a significant burden on the health care system. Amino acids constitute one of the most crucial metabolic products within the human body, and alterations in their metabolic pathways have been identified in the microenvironment of AIS, thereby influencing the pathogenesis, severity, and prognosis of AIS. The amino acid metabolism characteristics in AIS are complex. On one hand, the dynamic progression of AIS continuously reshapes the amino acid metabolism pattern. Conversely, changes in the amino acid metabolism pattern also exert a double-edged effect on AIS. This interaction is bidirectional, dynamic, heterogeneous, and dose-specific. Therefore, the distinctive metabolic reprogramming features surrounding amino acids during the AIS process are systematically summarized in this paper, aiming to provide potential investigative strategies for the early diagnosis, treatment approaches, and prognostic enhancement of AIS.

Systematic Insights into the Relationship between the Microbiota-Gut-Brain Axis and Stroke with the Focus on Tryptophan Metabolism

Stroke, as a serious cerebral vascular disease with high incidence and high rates of disability and mortality, has limited therapeutic options due to the narrow time window. Compelling evidence has highlighted the significance of the gut microbiota and gut-brain axis as critical regulatory factors affecting stroke. Along the microbiota-gut-brain axis, tryptophan metabolism further acquires increasing attention for its intimate association with central nervous system diseases. For the purpose of exploring the potential role of tryptophan metabolism in stroke and providing systematic insights into the intricate connection of the microbiota-gut-brain axis with the pathological procedure of stroke, this review first summarized the practical relationship between microbiota and stroke by compiling the latest case-control research. Then, the microbiota-gut-brain axis, as well as its interaction with stroke, were comprehensively elucidated on the basis of the basic anatomical structure and physiological function. Based on the crosstalk of microbiota-gut-brain, we further focused on the tryptophan metabolism from the three major metabolic pathways, namely, the kynurenine pathway, serotonin pathway, and microbial pathway, within the axis. Moreover, the effects of tryptophan metabolism on stroke were appreciated and elaborated here, which is scarcely found in other reviews. Hopefully, the systematic illustration of the mechanisms and pathways along the microbiota-gut-brain axis will inspire more translational research from metabolic perspectives, along with more attention paid to tryptophan metabolism as a promising pharmaceutical target in order to reduce the risk of stroke, mitigate the stroke progression, and ameliorate the stroke prognosis.

Prenatal exposure to environmental contaminants and cord serum metabolite profiles in future immune-mediated diseases

BACKGROUND

Prenatal exposure to environmental contaminants is a significant health concern because it has the potential to interfere with host metabolism, leading to adverse health effects in early childhood and later in life. Growing evidence suggests that genetic and environmental factors, as well as their interactions, play a significant role in the development of autoimmune diseases.

OBJECTIVE

In this study, we hypothesized that prenatal exposure to environmental contaminants impacts cord serum metabolome and contributes to the development of autoimmune diseases.

METHODS

We selected cord serum samples from All Babies in Southeast Sweden (ABIS) general population cohort, from infants who later developed one or more autoimmune-mediated and inflammatory diseases: celiac disease (CD), Crohn's disease (IBD), hypothyroidism (HT), juvenile idiopathic arthritis (JIA), and type 1 diabetes (T1D) (all cases, N = 62), along with matched controls (N = 268). Using integrated exposomics and metabolomics mass spectrometry (MS) based platforms, we determined the levels of environmental contaminants and metabolites.

RESULTS

Differences in exposure levels were found between the controls and those who later developed various diseases. High contaminant exposure levels were associated with changes in metabolome, including amino acids and free fatty acids. Specifically, we identified marked associations between metabolite profiles and exposure levels of deoxynivalenol (DON), bisphenol S (BPS), and specific per- and polyfluorinated substances (PFAS).

IMPACT STATEMENT

Abnormal metabolism is a common feature preceding several autoimmune and inflammatory diseases. However, few studies compared common and specific metabolic patterns preceding these diseases. Here we hypothesized that exposure to environmental contaminants impacts cord serum metabolome, which may contribute to the development of autoimmune diseases. We found differences in exposure levels between the controls and those who later developed various diseases, and importantly, on the metabolic changes associated with the exposures. High contaminant exposure levels were associated with specific changes in metabolome. Our study suggests that prenatal exposure to specific environmental contaminants alters the cord serum metabolomes, which, in turn, might increase the risk of various immune-mediated diseases.

CDCS-TCM: A framework based on complex network theory to analyze the causality and dynamic correlation of substances in the metabolic process of traditional Chinese medicine

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine, with the feature of synergistic effects of multi-component, multi-pathway and multi-target, plays an important role in the treatment of cancer, cardiovascular and cerebrovascular diseases, etc. However, chemical components in traditional Chinese medicine are complex and most of the pharmacological mechanisms remain unclear, especially the relationships of chemical components change during the metabolic process.

AIM OF STUDY

Our aim is to provide a method based on complex network theory to analyze the causality and dynamic correlation of substances in the metabolic process of traditional Chinese medicine.

MATERIALS AND METHODS

We proposed a framework named CDCS-TCM to analyze the causality and dynamic correlation between substances in the metabolic process of traditional Chinese medicine. Our method mainly consists two parts. The first part is to discover the local and global causality by the causality network. The second part is to investigate the dynamic correlations and identify the essential substance by dynamic substance correlation network.

RESULTS

We developed a CDCS-TCM method to analyze the causality and dynamic correlation of substances. Using the XiangDan Injection for ischemic stroke as an example, we have identified the important substances in the metabolic process including substance pairs with strong causality and the dynamic changes of the core effector substance clusters.

CONCLUSION

The proposed framework will be useful for exploring the correlations of active ingredients in traditional Chinese medicine more effectively and will provide a new perspective for the elucidation of drug action mechanisms and the new drug discovery.

Imidacloprid-induced lung injury in mice: Activation of the PI3K/AKT/NF-κB signaling pathway via TLR4 receptor engagement

Significant impairment of pulmonary function has been demonstrated through long-term exposure to neonicotinoid insecticides, such as imidacloprid (IMI). However, the underlying mechanisms of lung injury induced by IMI remain unclear. In this study, a mouse model of IMI-induced pulmonary injury was established, and the toxicity and lung damage were assessed through mouse body weight, organ index, hematological parameters, and histopathological analysis of lung tissues. Furthermore, metabolomics and transcriptomics techniques were employed to explore the mechanistic aspects. Results from the toxicity assessments indicated that mouse body weight was significantly reduced by IMI, organ index was disturbed, and hematological parameters were disrupted, resulting in pulmonary injury. The mechanistic experimental results indicate that the differences in metabolites and gene expression in mouse lungs could be altered by IMI. Validation of the results through combined analysis of metabolomics and transcriptomics revealed that the mechanism by which IMI induces lung injury in mice might be associated with the activation of the TLR4 receptor, thereby activating the PI3K/AKT/NF-κB signaling pathway to induce inflammation in mouse lungs. This study provided valuable insights into the mechanisms underlying IMI-induced pulmonary damage, potentially contributing to the development of safer pest control strategies. The knowledge gained served as a robust scientific foundation for the prevention and treatment of IMI-related pulmonary injuries.

Pathological shifts in tryptophan metabolism in human term placenta exposed to LPS or poly I:C†

Maternal immune activation during pregnancy is a risk factor for offspring neuropsychiatric disorders. Among the mechanistic pathways by which maternal inflammation can affect fetal brain development and programming, those involving tryptophan (TRP) metabolism have drawn attention because various TRP metabolites have neuroactive properties. This study evaluates the effect of bacterial (lipopolysaccharides/LPS) and viral (polyinosinic:polycytidylic acid/poly I:C) placental infection on TRP metabolism using an ex vivo model. Human placenta explants were exposed to LPS or poly I:C, and the release of TRP metabolites was analyzed together with the expression of related genes and proteins and the functional activity of key enzymes in TRP metabolism. The rate-limiting enzyme in the serotonin pathway, tryptophan hydroxylase, showed reduced expression and functional activity in explants exposed to LPS or poly I:C. Conversely, the rate-limiting enzyme in the kynurenine pathway, indoleamine dioxygenase, exhibited increased activity, gene, and protein expression, suggesting that placental infection mainly promotes TRP metabolism via the kynurenine (KYN) pathway. Furthermore, we observed that treatment with LPS or poly I:C increased activity in the kynurenine monooxygenase branch of the KYN pathway. We conclude that placental infection impairs TRP homeostasis, resulting in decreased production of serotonin and an imbalance in the ratio between quinolinic acid and kynurenic acid. This disrupted homeostasis may eventually expose the fetus to suboptimal/toxic levels of neuroactive molecules and impair fetal brain development.

The paradigm change from reactive medical services to 3PM in ischemic stroke: a holistic approach utilising tear fluid multi-omics, mitochondria as a vital biosensor and AI-based multi-professional data interpretation

Worldwide stroke is the second leading cause of death and the third leading cause of death and disability combined. The estimated global economic burden by stroke is over US$891 billion per year. Within three decades (1990-2019), the incidence increased by 70%, deaths by 43%, prevalence by 102%, and DALYs by 143%. Of over 100 million people affected by stroke, about 76% are ischemic stroke (IS) patients recorded worldwide. Contextually, ischemic stroke moves into particular focus of multi-professional groups including researchers, healthcare industry, economists, and policy-makers. Risk factors of ischemic stroke demonstrate sufficient space for cost-effective prevention interventions in primary (suboptimal health) and secondary (clinically manifested collateral disorders contributing to stroke risks) care. These risks are interrelated. For example, sedentary lifestyle and toxic environment both cause mitochondrial stress, systemic low-grade inflammation and accelerated ageing; inflammageing is a low-grade inflammation associated with accelerated ageing and poor stroke outcomes. Stress overload, decreased mitochondrial bioenergetics and hypomagnesaemia are associated with systemic vasospasm and ischemic lesions in heart and brain of all age groups including teenagers. Imbalanced dietary patterns poor in folate but rich in red and processed meat, refined grains, and sugary beverages are associated with hyperhomocysteinaemia, systemic inflammation, small vessel disease, and increased IS risks. Ongoing 3PM research towards vulnerable groups in the population promoted by the European Association for Predictive, Preventive and Personalised Medicine (EPMA) demonstrates promising results for the holistic patient-friendly non-invasive approach utilising tear fluid-based health risk assessment, mitochondria as a vital biosensor and AI-based multi-professional data interpretation as reported here by the EPMA expert group. Collected data demonstrate that IS-relevant risks and corresponding molecular pathways are interrelated. For examples, there is an evident overlap between molecular patterns involved in IS and diabetic retinopathy as an early indicator of IS risk in diabetic patients. Just to exemplify some of them such as the 5-aminolevulinic acid/pathway, which are also characteristic for an altered mitophagy patterns, insomnia, stress regulation and modulation of microbiota-gut-brain crosstalk. Further, ceramides are considered mediators of oxidative stress and inflammation in cardiometabolic disease, negatively affecting mitochondrial respiratory chain function and fission/fusion activity, altered sleep-wake behaviour, vascular stiffness and remodelling. Xanthine/pathway regulation is involved in mitochondrial homeostasis and stress-driven anxiety-like behaviour as well as molecular mechanisms of arterial stiffness. In order to assess individual health risks, an application of machine learning (AI tool) is essential for an accurate data interpretation performed by the multiparametric analysis. Aspects presented in the paper include the needs of young populations and elderly, personalised risk assessment in primary and secondary care, cost-efficacy, application of innovative technologies and screening programmes, advanced education measures for professionals and general population-all are essential pillars for the paradigm change from reactive medical services to 3PM in the overall IS management promoted by the EPMA.

The identification of key metabolites and mechanisms during isoniazid/rifampicin-induced neurotoxicity and hepatotoxicity in a mouse model by HPLC-TOF/MS-based untargeted urine metabolomics

The co-administration of isoniazid (INH) and rifampicin (RIF) is associated with hepatotoxicity and neurotoxicity. To systematically investigate the mechanisms of hepatotoxicity and neurotoxicity induced by INH/RIF, we used high performance liquid chromatography-time of flight mass spectrometry (HPLC-TOF/MS)-based untargeted metabolomics to analyze urine from a mouse model and screened a range of urinary biomarkers. Mice were orally co-administered with INH (120 mg/kg) and RIF (240 mg/kg) and urine samples were collected on days 0, 7, 14 and 21. Hepatotoxicity and neurotoxicity were assessed by samples of liver, brain and kidney tissue which were harvested for histological analysis. Toxicity analysis revealed that INH/RIF caused hepatotoxicity and neurotoxicity in a time-dependent manner; compared with day 0, the levels of 35, 82 and 86 urinary metabolites were significantly different on days 7, 14 and 21, respectively. Analysis showed that by day 21, exposure to INH+RIF had caused disruption in vitamin B6 metabolism; the biosynthesis of unsaturated fatty acids; tyrosine, taurine, hypotaurine metabolism; the synthesis of ubiquinone and other terpenoid-quinones; and the metabolism of tryptophan, nicotinate and nicotinamide. Nicotinic acid, nicotinuric acid and kynurenic acid were identified as sensitive urinary biomarkers that may be useful for the diagnosis and evaluation of toxicity.

Normative Data on Serum and Plasma Tryptophan and Kynurenine Concentrations from 8089 Individuals Across 120 Studies: A Systematic Review and Meta-Analysis

In this systematic review and meta-analysis, a normative dataset is generated from the published literature on the kynurenine pathway in control participants extracted from case-control and methodological validation studies. Study characteristics were mapped, and studies were evaluated in terms of analytical rigour and methodological validation. Meta-analyses of variance between types of instruments, sample matrices and metabolites were conducted. Regression analyses were applied to determine the relationship between metabolite, sample matrix, biological sex, participant age and study age. The grand mean concentrations of tryptophan in the serum and plasma were 60.52 ± 15.38 μM and 51.45 ± 10.47 μM, respectively. The grand mean concentrations of kynurenine in the serum and plasma were 1.96 ± 0.51 μM and 1.82 ± 0.54 μM, respectively. Regional differences in metabolite concentrations were observed across America, Asia, Australia, Europe and the Middle East. Of the total variance within the data, mode of detection (MOD) accounted for up to 2.96%, sample matrix up to 3.23%, and their interaction explained up to 1.53%; the latter of which was determined to be negligible. This review was intended to inform future empirical research and method development studies and successfully synthesised pilot data. The pilot data reported in this study will inform future precision medicine initiatives aimed at targeting the kynurenine pathway by improving the availability and quality of normative data.

Effect of In Ovo Administration of a Multi-Strain Probiotic and Zinc Glycine Chelate on Antioxidant Capacity and Selected Immune Parameters in Newly Hatched Chicks

The aim of this study was to determine the effect of in ovo co-supplementation of chicken embryos with a multi-strain probiotic containing effective microorganisms and zinc glycine chelate on total antioxidant capacity; concentrations of sulfhydryl groups, bityrosine bridges, formylkynurenines, hydroperoxides, proteins, corticosterone, pro- and anti-inflammatory cytokines and heat shock proteins; and the activity of catalase and superoxide dismutase in the serum, yolk sac and tissues of broiler chickens at 12 h and at 7 days after hatching. The results indicate high SOD activity in the small and large intestines of chicks at 12 h post-hatch in the groups receiving the multi-strain probiotic and in the small intestine and yolk sac of birds receiving the multi-strain probiotic and Zn-Gly chelate. High concentrations of TNF-α and IFN-γ in the yolk sac and serum after in ovo administration of Zn-Gly chelate were observed 12 h after hatching. The use of a probiotic and a probiotic with Zn-Gly chelate increased the total antioxidant capacity in the tissues of chickens. It can be concluded that in ovo administration of a multi-strain probiotic and Zn-Gly chelate can maintain the oxidant/antioxidant balance in chickens and increase the defense capacity against oxidative stress.

Pathway-level multi-omics analysis of the molecular mechanisms underlying the toxicity of long-term tacrolimus exposure

Tacrolimus (TAC)-based treatment is associated with nephrotoxicity and hepatotoxicity; however, the underlying molecular mechanisms responsible for this toxicity have not been fully explored. This study elucidated the molecular processes underlying the toxic effects of TAC using an integrative omics approach. Rats were sacrificed after 4 weeks of daily oral TAC administration at a dose of 5 mg/kg. The liver and kidney underwent genome-wide gene expression profiling and untargeted metabolomics assays. Molecular alterations were identified using individual data profiling modalities and further characterized by pathway-level transcriptomics-metabolomics integration analysis. Metabolic disturbances were mainly related to an imbalance in oxidant-antioxidant status, as well as in lipid and amino acid metabolism in the liver and kidney. Gene expression profiles also indicated profound molecular alterations, including in genes associated with a dysregulated immune response, proinflammatory signals, and programmed cell death in the liver and kidney. Joint-pathway analysis indicated that the toxicity of TAC was associated with DNA synthesis disruption, oxidative stress, and cell membrane permeabilization, as well as lipid and glucose metabolism. In conclusion, our pathway-level integration of transcriptome and metabolome and conventional analyses of individual omics profiles, provided a more comprehensive picture of the molecular changes resulting from TAC toxicity. This study also serves as a valuable resource for subsequent investigations aiming to understand the mechanism underlying the molecular toxicology of TAC.

Tryptophan metabolism in health and disease

Tryptophan (Trp) metabolism primarily involves the kynurenine, 5-hydroxytryptamine, and indole pathways. A variety of bioactive compounds produced via Trp metabolism can regulate various physiological functions, including inflammation, metabolism, immune responses, and neurological function. Emerging evidence supports an intimate relationship between Trp metabolism disorder and diseases. The levels or ratios of Trp metabolites are significantly associated with many clinical features. Additionally, studies have shown that disease progression can be controlled by modulating Trp metabolism. Indoleamine-2,3-dioxygenase, Trp-2,3-dioxygenase, kynurenine-3-monooxygenase, and Trp hydroxylase are the rate-limiting enzymes that are critical for Trp metabolism. These key regulatory enzymes can be targeted for treating several diseases, including tumors. These findings provide novel insights into the treatment of diseases. In this review, we have summarized the recent research progress on the role of Trp metabolites in health and disease along with their clinical applications.

L-tryptophan-titanium oxide nanoparticles showed selective anti-Toxoplasma gondii activity and improved host biocompatibility

Toxoplasma gondii, the etiological agent of toxoplasmosis, currently affects nearly one-third of the human population. Treatment options for toxoplasmosis are limited, which underscores the need for new drugs. In the present study, we screened nanoparticles (NPs) of titanium dioxide (TiO₂) and molybdenum (Mo) for their potential to inhibit the growth of T. gondii in vitro. NPs of TiO₂ and Mo showed non-dose-dependent anti-T. gondii activity with EC₅₀ values of 157.6 and 253 µg/mL, respectively. Previously, we showed that amino acid modification of NPs enhances their selective anti-parasite toxicity. Therefore, to enhance the selective anti-parasitic action of TiO₂, we modified the NP surface using alanine, aspartate, arginine, cysteine, glutamate, tryptophan, tyrosine, and bovine serum albumin. The bio-modified TiO₂ showed anti-parasite activity with EC₅₀ values ranging from 45.7 to 286.4 µg/mL. At effective anti-parasite concentrations, modified-TiO₂ showed no appreciable host cytotoxicity. Of the eight bio-modified TiO₂, tryptophan-TiO₂ showed the most promising anti-T. gondii specificity and improved host biocompatibility with a selectivity index (SI) of 49.1 versus 7.5 for TiO₂ (note, pyrimethamine, a standard drug for toxoplasmosis, has an SI of 2.3). Furthermore, our data indicate that redox modulation may be part of the anti-parasite action of these NPs. Indeed, augmentation with trolox and l-tryptophan reversed the growth restriction caused by the tryptophan-TiO₂ NPs. Collectively, these findings suggest that the parasite toxicity was selective and not a result of general cytotoxic action. Furthermore, surface modification with amino acids such as l-tryptophan not only enhanced the anti-parasitic action of TiO₂ but also improved the host biocompatibility. Overall, our findings indicate that the nutritional requirements of T. gondii represent a viable target for the development of new and effective anti-T. gondii agents.

Neurodegenerative and Neurodevelopmental Diseases and the Gut-Brain Axis: The Potential of Therapeutic Targeting of the Microbiome

The human gut microbiome contains the largest number of bacteria in the body and has the potential to greatly influence metabolism, not only locally but also systemically. There is an established link between a healthy, balanced, and diverse microbiome and overall health. When the gut microbiome becomes unbalanced (dysbiosis) through dietary changes, medication use, lifestyle choices, environmental factors, and ageing, this has a profound effect on our health and is linked to many diseases, including lifestyle diseases, metabolic diseases, inflammatory diseases, and neurological diseases. While this link in humans is largely an association of dysbiosis with disease, in animal models, a causative link can be demonstrated. The link between the gut and the brain is particularly important in maintaining brain health, with a strong association between dysbiosis in the gut and neurodegenerative and neurodevelopmental diseases. This link suggests not only that the gut microbiota composition can be used to make an early diagnosis of neurodegenerative and neurodevelopmental diseases but also that modifying the gut microbiome to influence the microbiome-gut-brain axis might present a therapeutic target for diseases that have proved intractable, with the aim of altering the trajectory of neurodegenerative and neurodevelopmental diseases such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, autism spectrum disorder, and attention-deficit hyperactivity disorder, among others. There is also a microbiome-gut-brain link to other potentially reversible neurological diseases, such as migraine, post-operative cognitive dysfunction, and long COVID, which might be considered models of therapy for neurodegenerative disease. The role of traditional methods in altering the microbiome, as well as newer, more novel treatments such as faecal microbiome transplants and photobiomodulation, are discussed.

Kynurenine pathway of tryptophan metabolism in patients with familial Mediterranean fever

BACKGROUND

Familial Mediterranean fever (FMF) is an autoinflammatory syndrome characterized by recurrent episodes of fever and aseptic polyserositis. Subclinical inflammation generates a hidden threat to the development of FMF complications such as amyloidosis in attack-free intervals. The kynurenine pathway (KP) has been considered an important player in inflammation and immune response. The study was aimed to measure serum levels of KP metabolites in patients with FMF in the attack-free period.

METHODS

A total of 161 participants were recruited from the rheumatology department in this single-centre, case-control study. Participants meeting the eligibility criteria were divided into healthy controls (n = 80) and FMF (n = 81). The laboratory data were obtained from the electronic registration database. Serum tryptophan (TRP), kynurenine (KYN), kynurenic acid (KYNA), 3-hydroxyanthranilic acid, 3-hydroxykynurenine (3HK), and quinolinic acid (QUIN) concentrations were measured with tandem mass spectrometry. Laboratory findings of FMF patients and healthy controls subjects were compared and evaluated.

RESULTS

Serum TRP and KYNA levels were significantly decreased in both FMF groups compared to the control group, while the levels of KYN, QUIN, 3HK, the KYN/TRP ratio, and red cell distribution width were higher.

CONCLUSION

TRP degradation by the KP is increased in patients with FMF. KP metabolites can be useful in demonstrating subclinical inflammation.

Oxidative Stress as a Reliable Biomarker of Carotid Plaque Instability: A Pilot Study

Background: Predicting stroke risk in patients with carotid artery stenosis (CS) remains challenging. Circulating biomarkers seem to provide improvements with respect to risk stratification. Methods: Study patients who underwent carotid endarterectomy were categorized into four groups according to symptomatology and compared as follows: symptomatic with asymptomatic patients; and asymptomatic patients including amaurosis fugax (AF) (asymptomatic + AF group) with patients with a transient ischemic attack (TIA) or brain stroke (BS) (hemispheric brain stroke group). Carotid specimens were histologically analyzed and classified based on the American Heart Classification (AHA) standard. As a marker of OS, the plasma levels of malondialdehyde (MDA) were measured. Comparisons of MDA plasma levels between groups were analyzed. Results: In total, 35 patients were included in the study. There were 22 (63%) patients in the asymptomatic group and 13 (37%) in the symptomatic group. Atheromatous plaque (p = 0.03) and old hemorrhage (p = 0.05), fibrous plaque (p = 0.04), myxoid changes (p = 0.02), plaques without hemorrhage (p = 0.04), significant neovascularization (p = 0.04) and AHA classification (p = 0.006) had significant correlations with clinical presentation. There were 26 (74%) patients in the asymptomatic group and 9 (26%) in the hemispheric brain stroke group. Atheromatous plaque (p = 0.02), old hemorrhage (p = 0.05) and plaques without neovascularization (p = 0.02), fibrous plaque (p = 0.03), plaques without hemorrhage (p = 0.02) and AHA classification (p = 0.01) had significant correlations with clinical presentation. There was no significant difference between symptomatic and asymptomatic groups with respect to MDA plasma levels (p = 0.232). A significant difference was observed when MDA plasma levels were compared to asymptomatic + AF and the hemispheric stroke group (p = 0.002). Conclusions: MDA plasma level correlates with the risk of hemispheric stroke (TIA or BS) and is a reliable marker of plaque vulnerability in carotid artery stenosis.

Microbiota of the gastrointestinal tract: Friend or foe?

The gut microbiota is currently considered an external organ of the human body that provides important mechanisms of metabolic regulation and protection. The gut microbiota encodes over 3 million genes, which is approximately 150 times more than the total number of genes present in the human genome. Changes in the qualitative and quantitative composition of the microbiome lead to disruption in the synthesis of key bacterial metabolites, changes in intestinal barrier function, and inflammation and can cause the development of a wide variety of diseases, such as diabetes, obesity, gastrointestinal disorders, cardiovascular issues, neurological disorders and oncological concerns. In this review, I consider issues related to the role of the microbiome in the regulation of intestinal barrier function, its influence on physiological and pathological processes occurring in the body, and potential new therapeutic strategies aimed at restoring the gut microbiome. Herewith, it is important to understand that the gut microbiota and human body should be considered as a single biological system, where change of one element will inevitably affect its other components. Thus, the study of the impact of the intestinal microbiota on health should be considered only taking into account numerous factors, the role of which has not yet been fully elucidated.

Integration of metabolomics and proteomics analysis to explore the mechanism of neurotoxicity induced by receipt of isoniazid and rifampicin in mice

Isoniazid (INH) and rifampicin (RIF) are co-administered in tuberculosis treatment but can cause neurotoxicity, and the mechanism is not known. To explore this mechanism, we employed an integrated approach using metabolomics analysis (MA) and proteomics analysis (PA). Male mice were divided into three groups and administered vehicle (control group), or co-administered INH (120 mg/kg) and RIF (240 mg/kg), for 7 or 14 days. Mice brains were collected for mass spectrometry-based PA and MA plus lipidomics analysis. Measurement of brain levels of malondialdehyde and superoxide dismutase revealed time-dependent brain injury after exposure to INH+RIF for 7 and 14 days. Also, 422 proteins, 35 metabolites, and 21 lipids were dysregulated and identified. MA demonstrated "purine metabolism," "phenylalanine, tyrosine and tryptophan biosynthesis," "biosynthesis of unsaturated fatty acids," "phenylalanine metabolism," and "arginine biosynthesis" to be disturbed significantly. PA demonstrated pathways such as "lipids," "amino acids," and "energy metabolism" to be disrupted. Peroxisome proliferator-activated receptor (PPAR) pathways were changed in energy metabolism, which led to the neurotoxicity induced by INH+RIF. Immunohistochemical analyses of PPARs in mice brains verified that PPAR-α and -γ expression was downregulated. PPAR-α and -γ activation might be a key target for alleviating INH+RIF-induced neurotoxicity.

Exploration of the underlying mechanisms of isoniazid/rifampicin-induced liver injury in mice using an integrated proteomics and metabolomics approach

The hepatotoxic mechanism resulting from coadministration of isoniazid (INH) and rifampicin (RIF) are complex and studies remain inconclusive. To systematically explore the underlying mechanisms, an integrated mass-based untargeted metabolomics and label-free quantitative proteomics approach was used to clarify the mechanism of INH/RIF-induced liver injury. Thirty male mice were randomly divided into three groups: control (receiving orally administered vehicle solution), INH (150 mg/kg) + RIF (300 mg/kg) orally administered for either 7 or 14 days, respectively. Serum was collected for the analysis of biochemical parameters and liver samples were obtained for mass spectrum-based proteomics, metabolomics, and lipidomics analysis. Overall, 511 proteins, 31 metabolites, and 23 lipids were dysregulated and identified, and disordered biological pathways were identified. The network of integrated multiomics showed that glucose, lipid, and amino acid metabolism as well as energy metabolism were mainly dysregulated and led to oxidative stress, inflammation, liver steatosis, and cell death induced by INH and RIF. Coadministration of INH and RIF can induce liver injury by oxidative stress, inflammation, liver steatosis, and cell death, and the reduction in glutathione levels may play a critical role in these systematic changes and warrants further study.

Serum Kynurenic Acid and Kynurenine Are Negatively Associated with the Risk of Adult Moyamoya Disease

Background and aim. Kynurenine (KYN) and kynurenic acid (KYNA) are key intermediate metabolites associated with inflammation and immune responses in the kynurenine pathway. It remains unknown whether KYN or KYNA is associated with the risk of adult moyamoya disease (MMD). The aim of this study was to prospectively investigate the association between serum KYN or KYNA and the risk of adult MMD. Methods. The study was conducted from July 2020 to December 2021. We measured serum KYN and KYNA levels for 360 adult MMD patients (259 cases of ischemic MMD, 101 cases of hemorrhagic MMD) and 89 age-sex-matched healthy controls. Clinical and laboratory characteristics were collected from the medical record. Results. After multivariate adjustment, decreased serum KYNA (OR, 0.085; 95% CI, 0.035−0.206; p = 0.000) or KYN (OR, 0.430; 95% CI, 0.225−0.820; p = 0.010) levels were associated with increased risk of MMD when upper and lower tertiles were compared. In addition, a higher trend of hemorrhagic MMD was found in MMD patients in KYNA tertile 1 compared with those in tertile 2 to 3 (OR, 0.584; 95% CI, 0.345−0.987; p = 0.044). Addition of serum KYNA (net reclassification improvement: 73.24%, p = 0.000; integrated discrimination improvement: 9.60%, p = 0.000) or KYN (integrated discrimination improvement: 1.70%, p = 0.037) to conventional risk factors significantly improved the risk prediction of MMD. In the exploratory analysis, we observed an interaction between KYN and age (≥40 versus <40 years) or homocysteine levels (≥13.0 versus <13.0 μmol/L) on the risk of MMD. Conclusions. Decreased serum KYNA or KYN levels were associated with an increased risk of adult MMD, suggesting that serum KYNA or KYN may be a valuable predictive biomarker for adult MMD.

Sex as a biological variable in determining the metabolic changes influencing acute ischemic stroke outcomes-Where is the data: A systematic review

Women continue to face a greater lifetime morbidity and mortality from stroke and have been shown to respond differently to stroke treatments compared to men. Since 2016, updated National Institutes of Health (NIH) policies require research studies to consider sex as a biological variable. However, the way in which this policy affects study design, analysis, and reporting is variable, with few studies performing and reporting a subgroup analysis based on biological sex. In acute ischemic stroke, the underlying biological explanation for sex-based differences in patient outcomes and response to treatments remains understudied. We performed a systematic review of preclinical and clinical research studies that explored sex differences in the metabolic response to acute ischemic stroke as it relates to neurological outcomes. Through a literature search in Ovid Medline, Embase, and Web of Science, 1,004 potential references were identified for screening. After abstract and full-text review, we identified only two studies which assessed metabolic response to acute ischemic stroke (within 72 h of last known well) and neurological outcome [Barthel Index, modified Rankin Scale (mRS) or an equivalent in preclinical models] and reported results based on biological sex. One article was a preclinical rat model and the other a clinical cohort study. In both studies, metabolites involved in amino acid metabolism, energy metabolism, fat metabolism, or oxidative stress were identified. We review these results and link to additional articles that use metabolomics to identify metabolites differentially expressed by sex or regulated based on stroke outcomes, but not both. The results of this systematic review should not only help identify targets in need of further investigation to improve the understanding of sex differences in the pathophysiology of acute ischemic stroke, but also highlight the critical need to expand the incorporation of sex as a biological variable in acute stroke research beyond simply including both sexes and reporting the proportion of males/females in each population studied.

Serum and brain metabolomic study reveals the protective effects of Bai-Mi-Decoction on rats with ischemic stroke

Bai-Mi-Decoction (BMD), which is composed of Eugenia caryophyllata, Myristica fragrans, Moschus berezovskii, and Crocus sativu, is a characteristic TCM multi-herb formula for brain disease. However, the mechanism of protective effects of BMD on ischemic stroke (IS) still has not been clarified. Our study is designed to elucidate the protective effects and underlying mechanisms of BMD on IS by employing pharmacodynamic and serum and brain metabolomic methods. In this experiment, 90 adult male Sprague-Dawley rats were randomly divided into the sham operation group (SHAM, vehicle), middle cerebral artery occlusion-reperfusion injury model group (MCAO/R, vehicle), positive control group (NMDP, 36 mg/kg/day nimodipine), and low (BMDL, 0.805 g/kg/day), moderate (BMDM, 1.61 g/kg/day), and high (BMDH, 3.22 g/kg/day) dosage of BMD prophylactic administration groups. The drugs were dissolved in 0.5% CMC-Na and orally administered to rats with equal volumes (100 g/ml body weight) once a day for 14 consecutive days. Neurological deficit score, cerebral infarct volume, change in body weight, and serum NO, SOD, MDA, GSH, and GSSG levels were determined. Pathological abnormalities using hematoxylin and eosin staining and the expression of VEGF, caspase-3, and NF-κB were analyzed. Furthermore, serum and brain metabolic profiles were explored to reveal the underlying mechanism using UHPLC-QTOF-MS/MS technology. BMD exhibited significant neuroprotective effects on MCAO/R rats. As compared to the MCAO/R model group, it could reduce the neurological deficit score and cerebral infarct volume, increase body weight, enhance GSH, SOD, and GSSG activities, and decrease NO and MDA contents of MCAO/R rats. Meanwhile, BMD could ameliorate pathological abnormalities of MCAO/R rats through reducing neuronal loss, vacuolated spaces, shrunken neurons, and destructed neuron structure, as well as regulating the expression of VEGF, caspase-3, and NF-κB. UHPLC-QTOF-MS/MS-based serum and brain metabolomics analysis found a total of 53 differential metabolites between MCAO/R and SHAM groups, of which 30 were significantly regulated by BMD intervention, and further metabolic pathway analysis implied that the protective effects were mainly associated with amino acid and glycerophospholipid metabolisms. Our pharmacodynamic and metabolomic results revealed the neuroprotective effects of BMD on MCAO/R rats, and the underlying mechanisms were probably related to amino acid and glycerophospholipid metabolisms.

Crosstalk between the Gut and Brain in Ischemic Stroke: Mechanistic Insights and Therapeutic Options

There has been a significant amount of interest in the past two decades in the study of the evolution of the gut microbiota, its internal and external impacts on the gut, and risk factors for cerebrovascular disorders such as cerebral ischemic stroke. The network of bidirectional communication between gut microorganisms and their host is known as the microbiota-gut-brain axis (MGBA). There is mounting evidence that maintaining gut microbiota homeostasis can frequently enhance the effectiveness of ischemic stroke treatment by modulating immune, metabolic, and inflammatory responses through MGBA. To effectively monitor and cure ischemic stroke, restoring a healthy microbial ecology in the gut may be a critical therapeutic focus. This review highlights mechanistic insights on the MGBA in disease pathophysiology. This review summarizes the role of MGBA signaling in the development of stroke risk factors such as aging, hypertension, obesity, diabetes, and atherosclerosis, as well as changes in the microbiota in experimental or clinical populations. In addition, this review also examines dietary changes, the administration of probiotics and prebiotics, and fecal microbiota transplantation as treatment options for ischemic stroke as potential health benefits. It will become more apparent how the MGBA affects human health and disease with continuing advancements in this emerging field of biomedical sciences.

An Integrated Strategy of Chemical Fingerprint and Network Pharmacology for the Discovery of Efficacy-Related Q-Markers of Pheretima

Pheretima, one of the animal-derived traditional Chinese medicines, has been wildly used in various cardiovascular and cerebrovascular diseases, including stroke, coronary heart disease, hyperlipidemia, and hyperglycemia. However, it was still a big challenge to select the quality markers for Pheretima quality control. The fingerprint and network pharmacology-based strategy was proposed to screen the efficiency related quality markers (Q-Markers) of Pheretima. The ratio of sample to liquid, ultrasonic-extraction time, temperature, and power were optimized by orthogonal design, respectively. The chemical fingerprint of forty batches of Pheretima was established, and six common peaks were screened. The network pharmacology was used to construct the Pheretima-Components-Targets-Pathways-Stroke network. It was found that six potential efficacy Q-markers in Pheretima could exert the relaxing meridians effect to treat stroke through acting on multiple targets and regulating various pathways. A simple HPLC-DAD method was developed and validated to determine the efficacy Q-markers. Grey relational analysis was used to further verify the relation of potential efficiency related quality markers with the anticoagulation activity of Pheretima, which indicated that the contents of these markers exhibited high relationship with the anticoagulation activity. It was concluded that hypoxanthine, uridine, phenylalanine, inosine, guanosine, and tryptophan were selected as quality markers related to relaxing meridians to evaluate the quality of Pheretima. The fingerprint and network pharmacology-based strategy was proved to be a powerful strategy for the discovery of efficiency related Q-markers of Pheretima.

Resveratrol Alleviating the Ovarian Function Under Oxidative Stress by Alternating Microbiota Related Tryptophan-Kynurenine Pathway

Oxidative stress (OS) is a key factor regulating the systemic pathophysiological effects and one of the fundamental mechanisms associated with aging and fertility deterioration. Previous studies revealed that resveratrol (RV) exhibits a preventive effect against oxidative stress in the ovary. However, it remains unknown whether gut microbiota respond to resveratrol during an OS challenge. In Exp. 1, layers received intraperitoneal injection of tert-butyl hydroperoxide (tBHP) (0 or 800 μmol/kg BW) or received resveratrol diets (0 or 600 mg/kg) for 28 days. In Exp. 2, the role of intestinal microbiota on the effects of resveratrol on tBHP-induced oxidative stress was assessed through fecal microbiota transplantation (FMT). The OS challenge reduced the egg-laying rate and exhibited lower pre-hierarchical follicles and higher atretic follicles. Oral RV supplementation ameliorated the egg-laying rate reduction and gut microbiota dysbiosis. RV also reversed the tryptphan-kynurenine pathway, upregulated nuclear factor E2-related factor 2 (Nrf2) and silent information regulator 1(SIRT1) levels, and decreased the expression of forkhead box O1 (FoxO1) and P53. These findings indicated that the intestinal microbiota-related tryptophan-kynurenine pathway is involved in the resveratrol-induced amelioration of ovary oxidative stress induced by tBHP in the layer model, while SIRT1-P53/FoxO1 and Nrf2-ARE signaling pathway were involved in this process.

An Emerging Cross-Species Marker for Organismal Health: Tryptophan-Kynurenine Pathway

Tryptophan (TRP) is an essential dietary amino acid that, unless otherwise committed to protein synthesis, undergoes metabolism via the Tryptophan-Kynurenine (TRP-KYN) pathway in vertebrate organisms. TRP and its metabolites have key roles in diverse physiological processes including cell growth and maintenance, immunity, disease states and the coordination of adaptive responses to environmental and dietary cues. Changes in TRP metabolism can alter the availability of TRP for protein and serotonin biosynthesis as well as alter levels of the immune-active KYN pathway metabolites. There is now considerable evidence which has shown that the TRP-KYN pathway can be influenced by various stressors including glucocorticoids (marker of chronic stress), infection, inflammation and oxidative stress, and environmental toxicants. While there is little known regarding the role of TRP metabolism following exposure to environmental contaminants, there is evidence of linkages between chemically induced metabolic perturbations and altered TRP enzymes and KYN metabolites. Moreover, the TRP-KYN pathway is conserved across vertebrate species and can be influenced by exposure to xenobiotics, therefore, understanding how this pathway is regulated may have broader implications for environmental and wildlife toxicology. The goal of this narrative review is to (1) identify key pathways affecting Trp-Kyn metabolism in vertebrates and (2) highlight consequences of altered tryptophan metabolism in mammals, birds, amphibians, and fish. We discuss current literature available across species, highlight gaps in the current state of knowledge, and further postulate that the kynurenine to tryptophan ratio can be used as a novel biomarker for assessing organismal and, more broadly, ecosystem health.

Age-Associated Gut Dysbiosis, Marked by Loss of Butyrogenic Potential, Correlates With Altered Plasma Tryptophan Metabolites in Older People Living With HIV

BACKGROUND

Imbalance in tryptophan (TRP) metabolism and its neuroactive metabolites, serotonin and kynurenine (KYN), is a known pathogenic mechanism underlying neurocognitive impairment. Gut microbiota plays an important role in TRP metabolism, and the production of these neuroactive molecules affects neurocognitive function. Although both HIV infection and normal aging independently induce gut dysbiosis and influence TRP metabolism, their interactive effects on compositional/functional changes in gut microbiota and consequent alterations in TRP metabolites remain largely undetermined.

METHODS

Older people living with HIV infection (PLWH, aged 50-70 years, n = 22) were enrolled in this cross-sectional pilot study. Metagenomic analysis of fecal microbiome using 16S Ribosomal ribonucleic acid gene sequencing and metabolomics analysis of plasma using mass spectrometry with a reverse-phase iquid chromatography tandem mass spectrometry were performed. Statistical analyses included the univariate linear regression and Spearman correlation analyses.

RESULTS

Age-associated changes in plasma levels of key neuroactive TRP metabolites, serotonin and KYN, were seen in PLWH. Specifically, we observed age-dependent decreases in serotonin and increases in KYN and KYN-to-TRP ratio, indicative of dysfunctional TRP metabolism. Furthermore, the gut dysbiosis seen in older PLWH is characterized by a reduction of Firmicutes/Bacteroidetes ratio and butyrate-producing microbial families Lachnospiraceae and Lactobacillaceae. Of importance, correspondent with gut dysbiosis, increasing age was significantly associated with decreased plasma butyrate levels, which in turn correlated positively with serotonin and negatively with KYN/TRP ratio.

CONCLUSIONS

Age-dependent gut microbial dysbiosis distinguished by a decrease in butyrogenic potential is a key pathogenic feature associated with the shift in TRP metabolism from serotonin to KYN in older PLWH.

Probiotic Bacillus Alleviates Oxidative Stress-Induced Liver Injury by Modulating Gut-Liver Axis in a Rat Model

Emerging evidence suggests a key role of gut microbiota in maintaining liver functions through modulating the gut–liver axis. In this study, we investigated whether microbiota alteration mediated by probiotic Bacillus was involved in alleviating oxidative stress- induced liver injury. Sprague–Dawley rats were orally administered Bacillus SC06 or SC08 for a 24-day period and thereafter intraperitoneally injected diquat (DQ) to induce oxidative stress. Results showed that Bacillus, particularly SC06 significantly inhibited hepatic injuries, as evidenced by the alleviated damaged liver structure, the decreased levels of ALT, AST, ALP and LDH, and the suppressed mitochondrial dysfunction. SC06 pretreatment markedly enhanced the liver antioxidant capacity by decreasing MDA and p47, and increasing T-AOC, SOD and HO-1.16S rRNA sequencing analysis revealed that DQ significantly changed the diversities and composition of gut microbiota, whereas Bacillus pretreatments could attenuate gut dysbiosis. Pearson’s correlation analysis showed that AST and MDA exerted a positive correlation with the opportunistic pathogenic genera and species (Escherichia and Shigella), and negatively correlated with the potential probiotics (Lactobacillus), while SOD exerted a reverse trend. The microbial metagenomic analysis demonstrated that Bacillus, particularly SC06 markedly suppress the metabolic pathways such as carbohydrate metabolism, lipid metabolism, amino acid metabolism and metabolism of cofactors and vitamins. Furthermore, SC06 decreased the gene abundance of the pathways mediating bacterial replication, secretion and pathogenicity. Taken together, Bacillus SC06 alleviates oxidative stress-induced liver injuries via optimizing the composition, metabolic pathways and pathogenic replication and secretion of gut microbiota. These findings elucidate the mechanisms of probiotics in alleviating oxidative stress and provide a promising strategy for preventing liver diseases by targeting gut microbiota.

Platelet, Plasma, Urinary Tryptophan-Serotonin-Kynurenine Axis Markers in Hyperacute Brain Ischemia Patients: A Prospective Study

Background and Purpose: Ischemic stroke is one of the most common causes of morbidity and mortality and has numerous clinical mimics. Previous studies have suggested a potential role of the tryptophan-serotonin (5-HT)-kynurenine (TSK) axis in ischemic stroke. Studies assessing this axis in the hyperacute phase of ischemic stroke (<4.5 h) are lacking. This prospective study thus evaluates the TSK axis in transient ischemic attack (TIA) and hyperacute ischemic stroke (AIS) patients.

Methods: This study included 28 patients (24 AIS and 4 TIA) and 29 controls. The blood and urine samples of patient were collected within 4.5 h of symptoms onset (day 0, D0), then at 24 h and 3 months. Control blood and urine samples were collected once (D0). The TSK axis markers measured were platelet serotonin transporter (SERT) and 5-HT_2A receptor (5-HT_2AR) densities and platelet, plasma, and urinary 5-HT, plasma and urinary 5-hydroxyindole acetic acid (5-HIAA), and plasma kynurenine and tryptophan (TRP) levels.

Results: At D0, patients exhibited a lower (p = 10⁻⁵) platelet SERT density, higher (p < 10⁻⁶) platelet 5-HT_2AR density, higher (p = 10⁻⁵) plasma kynurenine/tryptophan (K/T) ratio, and higher urinary 5-HT (p = 0.011) and 5-HIAA (p = 0.003) levels than controls.

Conclusions: We observed, for the first time, a hyperacute dysregulation of the serotonergic axis, and hyperacute and long-lasting activation of the tryptophan-kynurenine pathway in brain ischemia.

microRNA-181a promotes the oncogene S100A2 and enhances papillary thyroid carcinoma growth by mediating the expression of histone demethylase KDM5C

BACKGROUND AND PURPOSE

Papillary thyroid carcinoma (PTC) is an endocrine malignancy. Increasing evidence highlights microRNAs (miRNAs) as important participants in PTC. Here, we investigated the role of miR-181a in PTC.

METHODS

A microarray-based analysis was performed to identify the differential expression of miR-181a in PTC, which was validated with RT-qPCR. Protein expression of the proliferation-related factor Ki-67 and apoptosis- and migration-related factors in PTC was assessed with immunoblot analysis. A dual-luciferase reporter gene assay was adopted to verify the relationship between miR-181a and lysine demethylase 5C (KDM5C). Chromatin immunoprecipitation (ChIP) was used to detect the level of the H3K4me3 modification on S100 calcium-binding protein A2 (S100A2). Cell viability, apoptosis, and invasion and migration abilities were evaluated by Cell Counting Kit-8 (CCK-8), flow cytometry, and transwell assays, respectively. The in vitro results were verified in in vivo nude mouse models.

RESULTS

miR-181a was highly expressed in PTC tissues and cell lines. Silencing miR-181a repressed the proliferation and migration of PTC cells. KDM5C was identified as the target gene of miR-181a and represses S100A2 expression through histone demethylation to diminish the migration and proliferation of PTC cells. miR-181a depletion suppressed tumor growth.

CONCLUSION

Collectively, these results suggest that highly expressed miR-181a promotes the proliferation of PTC cells by increasing the expression of the oncogene S100A2. This study contributes to the advancement of miR-181a-targeted therapeutics.

Integration of Urine Proteomic and Metabolomic Profiling Reveals Novel Insights Into Neuroinflammation in Autism Spectrum Disorder

Autism spectrum disorder (ASD) comprises a group of neurodevelopmental disorders whose etiology and pathogenesis are not fully understood. To gain insight into the molecular basis of ASD, we performed comparative integrated proteomic and metabolomic analyses of urine samples from children diagnosed with ASD and healthy children. All 160 samples underwent proteomics analysis and 60 were analyzed by liquid chromatography-mass spectrometry to obtain metabolite profiles. We identified 77 differentially expressed proteins (DEPs; 21 downregulated and 56 upregulated) and 277 differentially expressed metabolites; 31 of the DEPs including glutathione, leukocyte antigens, glycoproteins, neural adhesion factors, and immunoglobulins, have been implicated in neuroinflammation. The proteomic analysis also revealed 8 signaling pathways that were significantly dysregulated in ASD patients; 3 of these (transendothelial leukocyte migration, antigen processing and presentation, and graft vs. host disease) were associated with the neuroimmune response. The metabolism of tryptophan, which is also related to the neuroimmune response, has been found to play a potential role in ASD. Integrated proteome and metabolome analysis showed that 6 signaling pathways were significantly enriched in ASD patients, 3 of which were correlated with impaired neuroinflammation (glutathione metabolism, metabolism of xenobiotics by cytochrome P450 and transendothelial migration of leukocyte). We also found a correlation between prostaglandin (PG) E2 levels and the inflammatory response in ASD. These results underscore the prominent role of the neuroimmune response in ASD and provide potential biomarkers that can be used for diagnosis or as targets for early intervention.

Tryptophan Metabolism in Central Nervous System Diseases: Pathophysiology and Potential Therapeutic Strategies

The metabolism of L-tryptophan (TRP) regulates homeostasis, immunity, and neuronal function. Altered TRP metabolism has been implicated in the pathophysiology of various diseases of the central nervous system. TRP is metabolized through two main pathways, the kynurenine pathway and the methoxyindole pathway. First, TRP is metabolized to kynurenine, then kynurenic acid, quinolinic acid, anthranilic acid, 3-hydroxykynurenine, and finally 3-hydroxyanthranilic acid along the kynurenine pathway. Second, TRP is metabolized to serotonin and melatonin along the methoxyindole pathway. In this review, we summarize the biological properties of key metabolites and their pathogenic functions in 12 disorders of the central nervous system: schizophrenia, bipolar disorder, major depressive disorder, spinal cord injury, traumatic brain injury, ischemic stroke, intracerebral hemorrhage, multiple sclerosis, Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and Huntington's disease. Furthermore, we summarize preclinical and clinical studies, mainly since 2015, that investigated the metabolic pathway of TRP, focusing on changes in biomarkers of these neurologic disorders, their pathogenic implications, and potential therapeutic strategies targeting this metabolic pathway. This critical, comprehensive, and up-to-date review helps identify promising directions for future preclinical, clinical, and translational research on neuropsychiatric disorders.

Relationships of Ischemic Stroke Occurrence and Outcome with Gene Variants Encoding Enzymes of Tryptophan Metabolism

Ischemic stroke is among the leading causes of mortality and long-term disability worldwide. Among stroke risk factors the importance of genetic background is gaining interest. There is a growing body of evidence of changes of metabolite levels and enzyme activities involved in the conversion of Trp during the course of cerebral ischemia. We compared the frequencies of ten SNPs of five genes related to Trp metabolism between groups of 122 ischemic stroke patients and 120 control individuals. Furthermore, we examined the mRNA levels of TPH1, IDO1 and KYAT1 genes in peripheral venous blood with the aim of assessing (i) whether there are changes in their expression during the course of stroke and (ii) does any of their investigated SNPs have an impact on gene expression. In seven cases out of ten studied polymorphisms we detected significant differences in frequencies in relation to ischemic stroke occurrence, etiology, and clinical parameters. We also detected changes in the expression of TPH1 and IDO1 genes during the course of the disease. We found that those IDO1 variants which show a trend towards elevated mRNA level are more frequent in stroke patients than in controls. Our results are important novel observations which suggest a causal relationship between elevated IDO1 expression and stroke etiology.

Viability of diffuse large B-cell lymphoma cells is regulated by kynurenine 3-monooxygenase activity

Diffuse large B-cell lymphoma (DLBCL) is a clinically heterogeneous lymphoid malignancy that is the most common type of lymphoma in Japan. Previous studies have demonstrated that patients with DLBCL have a poor prognosis due to increased levels of indoleamine 2,3-dioxygnase and kynurenine (KYN). However, the roles of metabolites acting downstream of KYN and associated enzymes are not fully understood. The present study investigated the role of kynurenine 3-monooxygenase (KMO), which catalyzes the conversion of KYN to 3-hydroxykynurenine (3-HK), using serum samples from patients with DLBCL and human DLBCL cell lines with different KMO expression [STR-428 cells with high levels of KMO expression (KMO^high) and KML-1 cells with low levels of KMO expression (KMO^low)]. Serum samples from 28 patients with DLBCL and 34 healthy volunteers were used to investigate the association between prognosis and KMO activity or 3-HK levels. Furthermore, to investigate the roles of KMO and its related metabolites, STR-428 and KML-1 cell lines, and the lymph nodes of patients with DLBCL were analyzed by reverse transcription-quantitative PCR for KMO, KYNU, 3-hydroxyanthranilate-3,4-dioxygenase and quinolinate phosphoribosyltransferase, by western blotting, and immunohistochemical or immunofluorescence staining for KMO, and by cell viability and NAD⁺/NADH assays. KYN pathway metabolites in serum samples were measured by HPLC. Serum 3-HK levels were regulated independently of serum KYN levels, and increased serum 3-HK levels and KMO activity were found to be associated with worse disease progression. Notably, the addition of KMO inhibitors and 3-HK negatively and positively regulated the viability of DLBCL cells, respectively. Furthermore, NAD⁺ levels in KMO^high STR-428 cells were significantly higher than those in KMO^low KML-1 cells. These results suggested that 3-HK generated by KMO activity may be involved in the regulation of DLBCL cell viability via NAD⁺ synthesis.

Vitamin B6 in Health and Disease

Vitamin B6 is a fascinating molecule involved in the vast majority of changes in the human body because it is a coenzyme involved in over 150 biochemical reactions. It is active in the metabolism of carbohydrates, lipids, amino acids, and nucleic acids, and participates in cellular signaling. It is an antioxidant and a compound with the ability to lower the advanced glycation end products (AGE) level. In this review, we briefly summarize its involvement in biochemical pathways and consider whether its deficiency may be associated with various diseases such as diabetes, heart disease, cancer, or the prognosis of COVID-19.

Altered kynurenine pathway metabolism in patients with ankylosing spondylitis

BACKGROUND

Various studies reported that increased proinflammatory cytokines in patients with ankylosing spondylitis (AS). Proinflammatory cytokines can affect the expression of various kynurenine pathway enzymes and therefore lead to metabolic changes that can affect the inflammatory response and immunity. Our aim was to measure serum levels of kynurenine pathway metabolites in patients with AS.

METHODS

The study included 85 patients with AS and 50 healthy volunteers. Serum tryptophan, kynurenine, kynurenic acid, 3-hydroxyanthranilic acid, 3-hydroxykynurenine, quinolinic acid concentrations were measured with tandem mass spectrometry. In addition, participants were divided into four groups according to the treatment regimen: TNF-α inhibitor group, conventional therapy group, control group and newly diagnosed AS group. These groups were compared in terms of kynurenine pathways metabolites, interleukin 6 (IL-6), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels.

RESULTS

Serum tryptophan, kynurenic acid, 3-hydroxykynurenine levels were significantly decreased (p < 0.05) in both AS groups compared to the control group, while the levels of kynurenine, quinolinic acid, CRP, ESR, and IL-6 were higher (p < 0.05). The Kynurenine/Tryptophan ratio and CRP levels of the conventional therapy and anti-TNF therapy group were significantly lower than the newly diagnosed AS patients (p < 0.05).

CONCLUSION

As a result of our study, we found that altered kynurenine pathway metabolism in patients with AS. Conventional therapy and anti-TNF-α therapy are effective in reducing the Kynurenine/Tryptophan ratio and CRP levels, although the effect of both treatments on other metabolites appears to be limited.

Lipidomic Analysis to Assess Oxidative Stress in Acute Coronary Syndrome and Acute Stroke Patients

Alterations in lipid metabolism mediated by oxidative stress play a key role in the process of atherosclerosis and superimposed thrombosis; these can lead to acute coronary syndrome (ACS) and acute ischemic stroke (AIS). Multiple studies have shown that the formation of atheromatous lesions is initiated by oxidation of low-density lipoproteins incorporated into the intima of the vessel wall. Here, we studied lipids in plasma samples from three cohorts: 61 patients with ACS (group A), 49 patients with AIS (group D), and 82 controls (group K). Untargeted lipidomics based on high-performance liquid chromatography coupled to mass spectrometry (UHPLC-HRMS) was employed to obtain comprehensive information on whether relationships exist between these patient categories based on lipid patterns. In addition, malondialdehyde (MDA) as a standard marker of oxidative stress was monitored. The most characteristic lipids in group K were fatty acyls of hydroxyfatty acids (FAHFAs). As expected, MDA concentrations were the lowest in group K. Our findings can better explain ongoing pathologies, both acute and chronic, with the potential for future diagnosis and treatment.