UPLC-QTOF/MS-Based Metabolomics Reveals the Protective Mechanism of Hydrogen on Mice with Ischemic Stroke

Molecular Hydrogen Therapy: Mechanisms, Delivery Methods, Preventive, and Therapeutic Application

Molecular hydrogen (H2), recognized as the smallest gas molecule, is capable of permeating cellular membranes and diffusing throughout the body. Due to its high bioavailability, H2 is considered a therapeutic gas for the treatment of various diseases. The therapeutic efficacy of hydrogen is contingent upon factors such as the administration method, duration of contact with diseased tissue, and concentration at targeted sites. H2 can be administered exogenously and is also produced endogenously within the intestinal tract. A comprehensive understanding of its delivery mechanisms and modes of action is crucial for advancing hydrogen medicine. This review highlights H₂'s mechanisms of action, summarizes its administration methods, and explores advancements in treating intestinal diseases (e.g., inflammatory bowel disease, intestinal ischemia-reperfusion, colorectal cancer). Additionally, its applications in managing other diseases are discussed. Finally, the challenges associated with its clinical application and potential solutions are explored. We propose that current delivery challenges faced by H2 can be effectively addressed through the use of nanoplatforms; furthermore, interactions between hydrogen and gut microbiota may provide insights into its mechanisms for treating intestinal diseases. Future research should explore the synergistic effects of H2 in conjunction with conventional therapies and develop personalized treatment plans to achieve precision medicine.

Polysaccharides extracted from Polygonatum sibiricum alleviate intestine-liver-kidney axis injury induced by citrinin and alcohol co-exposure in mice

Citrinin (Cit) is a metabolite of Monascus Aspergillus that is known to be nephrotoxic and affects the safety of Monascus products. Here, we investigated the effects of an intervention with bioactive Polygonatum sibiricum polysaccharides (PSPS) on Cit-induced toxic damage in populations with dietary patterns characterized by alcohol consumption. Our results showed that the PSPS intervention significantly increased the levels of intestinal Cit and its metabolite M1. Additionally, the PSPS intervention mitigated intestinal damage, as well as liver and kidney stress, and flora disruption induced by combined exposure to Cit and alcohol. It also promoted the recovery of Lactobacillus abundance. However, there was no significant improvement in hippocampal damage. Metabolomics analysis indicated that the PSPS significantly influenced the metabolic pathways involved in energy metabolism in liver and kidney, such as aspartic acid and tyrosine metabolism. Correlation analysis revealed a significant relationship between the reduction of Cit metabolites and the differential metabolites in the liver and kidney. Our results demonstrated that the PSPS intervention showed promise in improving intestinal flora imbalances, enhancing the barrier function against Cit, alleviating intestinal, liver, and kidney damage, and addressing the metabolic disorders along the gut-liver-kidney axis resulting from the co-exposure to Cit and alcohol.

The effect of taraxerol acetate extracted from dandelion on alleviating oxidative stress responses in vitro

Oxidative stress can be alleviated by antioxidants intakes. Taraxerol acetate (TA), a natural triterpenoid extracted from dandelions, may reduce the risk of metabolic disorders by regulating oxidative stress. In the study, we investigated the effects of TA in relieving oxidative stress in murine intestinal epithelial cells using multiomics techniques. Here, we found that TA activated the antioxidant defense system. Total antioxidant capacity (T-AOC) and Catalase (CAT) activity notably increased after TA treatment. Additionally, TA treatment effectively reduced the levels of lactate dehydrogenase (LDH) and malonaldehyde (MDA) and alleviated H2O2-induced oxidative stress. Furthermore, TA induced significant changes in the levels of 30 important metabolites. Specifically, it activated the complement and coagulation cascades, NF-κB and MAPK and glycerophospholipid pathways, resulting in altered transcript levels of related genes, such as Serpinb9e, SCD2, Hspa1b, and Hspa1a. Thus, the results demonstrated that TA potentially could promote health by alleviating H2O2-induced oxidative damage and provide valuable insights for its further development.

Serum lipidomic profiling of dairy calves fed milk replacers containing animal or vegetable fats

Vegetable fat blends are commonly used as fat sources in milk replacers (MR) for calves, but their composition differs considerably from that of bovine milk fat. The aim of this study was to investigate the serum lipid profile of preweaning calves fed twice-daily MR containing 30% fat (% DM). Upon arrival, 30 male Holstein-Friesian calves (BW = 45.6 ± 4.0 kg, age = 2.29 ± 0.8 d) were randomly assigned to 2 experimental diets (n = 15 per treatment): one MR was derived from either vegetable fats (VG; 65% rapeseed and 35% coconut fats) or animal fats (AN; 65% packers lard and 35% dairy cream). The 2 MR formulas contained 30% fat, 24% CP, and 36% lactose. Calves were housed indoors in individual pens with ad libitum access to chopped straw and water. Daily milk allowances were 6.0 L from d 1 to 5, 7.0 L from d 6 to 9, and 8.0 L from d 10 to 35, divided into 2 equal meals and prepared at 13.5% solids. An untargeted liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) method was employed to analyze the lipid profiles in the serum of calves sampled from the jugular vein at 35 d of age. In total, 594 lipids were characterized, comprising 25 different lipid classes. Principal component analysis (PCA) showed significant separation between VG and AN, indicating different lipid profiles in the serum. An orthogonal partial least squares discriminant analysis (OPLS-DA) classification model was used to further validate the distinction between the 2 treatment groups. The model exhibited a robust class separation and high predictive accuracy. Using a volcano plot (fold change threshold ≥1.5 and false discovery rate ≤0.05), it was observed that calves fed AN had higher levels of 39 lipid species in serum than calves fed VG, whereas 171 lipid species were lower in the AN group. Lipid classes, such as phosphatidylcholine (PC), phosphatidylethanolamine (PE), sphingomyelin (SM), triglycerides (TG), lysophosphatidylcholine (LPC), and lysophosphatidylethanolamine (LPE), were different. In particular, PC and PE were observed at lower levels in calves fed AN, possibly indicating shifts in cell membrane characteristics, intracellular signaling, and liver functions. In addition, a decrease in certain triglyceride (TG) species was observed in calves fed AN, including a decrease in TG species such as TG 36:0 and TG 38:0, possibly related to variations in the content of certain fatty acids within the AN MR, such as C10:0, C12:0, C14:0, and C18:0, compared with the VG MR. Calves fed AN had lower levels of LPC and LPE, and lysophosphatidylinositol, SM, and phosphatidylinositol species than calves fed VG, suggesting shifts in lipoprotein and lipid metabolic pathways. In conclusion, these results deepen the understanding of how lipid sources in MR can modulate the serum lipidome profiles of dairy calves.

The Untargeted Metabolomics Reveals Differences in Energy Metabolism in Patients with Different Subtypes of Ischemic Stroke

AIMS

Ischemic stroke (IS) is the most common subtype of stroke. The risk factors and pathogenesis of IS are complex and varied due to different subtypes. Therefore, we used metabolomics technology to investigate the biomarkers and potential pathophysiological mechanisms of different subtypes of IS.

METHODS

We included 126 IS patients and divided them into two groups based on the TOAST classification: large-artery atherosclerosis (LAA) group (n = 87) and small-vessel occlusion (SVO) group (n = 39). Plasma metabolomics analysis was performed using liquid chromatography-high-resolution mass spectrometry (LC-HRMS) to identify metabolic profiles in LAA and SVO subtype IS patients and to determine metabolic differences between patients with the two subtypes of IS.

RESULTS

We identified 26 differential metabolites between LAA and SVO subtype IS. A multiple prediction model based on the plasm metabolites had good predictive ability for IS subtyping (AUC = 0.822, accuracy = 77.8%), with 12,13-DHOME being the most important differential metabolite in the model. The differential metabolic pathways between the two subtypes of IS patients included tricarboxylic acid (TCA) cycle, alanine, aspartate and glutamate metabolism, and pyruvate metabolism, mainly focused on energy metabolism.

CONCLUSION

12,13-DHOME emerged as the primary discriminatory metabolite between LAA and SVO subtypes of IS. In LAA subtype IS patients, energy metabolism, encompassing pyruvate metabolism and the TCA cycle, exhibited lower activity levels when compared to patients with the SVO subtype IS. The utilization of targeted metabolomics holds the potential to improve diagnostic accuracy for distinguishing stroke subtypes.

Integrated single cell-RNA sequencing and Mendelian randomization for ischemic stroke and metabolic syndrome

Although more and more evidence has supported that metabolic syndrome (MS) is linked to ischemic stroke (IS), the molecular mechanism and genetic association between them has not been investigated. Here, we combined the existing single-cell RNA sequencing (scRNA-seq) data and mendelian randomization (MR) for stroke to understand the role of dysregulated metabolism in stroke. The shared hub genes were identified with machine learning and WGCNA. A total of six upregulated DEGs and five downregulated genes were selected for subsequent analyses. Nine genes were finally identified with random forest, Lasso regression, and XGBoost method as a potential diagnostic model. scRNA-seq also show the abnormal glycolysis level in most cell clusters in stroke and associated with the expression level of hub genes. The genetic relationship between IS and MS was verified with MR analysis. Our study reveals the common molecular profile and genetic association between ischemic stroke and metabolic syndrome.

Molecular Hydrogen: Emerging Treatment for Stroke Management

Ischemic stroke is a major cause of death and disability worldwide. However, only intravenous thrombolysis using mechanical thrombectomy or tissue plasminogen activator is considered an effective and approved treatment. Molecular hydrogen is an emerging therapeutic agent and has recently become a research focus. Molecular hydrogen is involved in antioxidative, anti-inflammatory, and antiapoptotic functions in normal physical processes and may play an important role in stroke management; it has been evaluated in numerous preclinical and clinical studies in several administration formats, including inhalation of hydrogen gas, intravenous or intraperitoneal injection of hydrogen-enriched solution, or drinking of hydrogen-enriched water. In addition to investigation of the underlying mechanisms, the safety and efficacy of using molecular hydrogen have been carefully evaluated, and favorable outcomes have been achieved. All available evidence indicates that molecular hydrogen may be a promising treatment option for stroke management in the future. This review aimed to provide an overview of the role of molecular hydrogen in the management of stroke and possible further modifications of treatment conditions and procedures in terms of dose, duration, and administration route.

Comparative analysis of the synergetic effects of Diwuyanggan prescription on high fat diet-induced non-alcoholic fatty liver disease using untargeted metabolomics

Non-alcoholic fatty liver disease (NAFLD) is one of the most common chronic liver disorders worldwide and had no approved pharmacological treatments. Diwuyanggan prescription (DWYG) is a traditional Chinese medicine preparation composed of 5 kinds of herbs, which has been used for treating chronic liver diseases in clinic. Whereas, the synergistic mechanism of this prescription for anti-NAFLD remains unclear. In this study, we aimed to demonstrate the synergetic effect of DWYG by using the disassembled prescriptions and untargeted metabolomics research strategies. The therapeutic effects of the whole prescription of DWYG and the individual herb were divided into six groups according to the strategy of disassembled prescriptions, including DWYG, Artemisia capillaris Thunb. (AC), Curcuma longa L. (CL), Schisandra chinensis Baill. (SC), Rehmannia glutinosa Libosch. (RG) and Glycyrrhiza uralensis Fisch. (GU) groups. The high fat diets-induced NAFLD mice model was constructed to evaluate the efficacy effects of DWYG. An untargeted metabolomics based on the UPLC-QTOF-MS/MS approach was carried out to make clear the synergetic effect on the regulation of metabolites dissecting the united mechanisms. Experimental results on animals revealed that the anti-NAFLD effect of DWYG prescription was better than the individual herb group in reducing liver lipid deposition and restoring the abnormality of lipidemia. In addition, further metabolomics analysis indicated that 23 differential metabolites associated with the progression of NAFLD were identified and 19 of them could be improved by DWYG. Compared with five single herbs, DWYG showed the most extensive regulatory effects on metabolites and their related pathways, which were related to lipid and amino acid metabolisms. Besides, each individual herb in DWYG was found to show different degrees of regulatory effects on NAFLD and metabolic pathways. SC and CL possessed the highest relationship in the regulation of NAFLD. Altogether, these results provided an insight into the synergetic mechanisms of DWYG from the metabolic perspective, and also supported a scientific basis for the rationality of clinical use of this prescription.

Molecular Hydrogen Mediates Neurorestorative Effects After Stroke in Diabetic Rats: the TLR4/NF-κB Inflammatory Pathway

Diabetes is an independent risk factor for stroke and amplifies inflammation. Diabetic stroke is associated with a higher risk of death and worse neural function. The identification of effective anti-inflammatory molecules with translational advantages is particularly important to promote perioperative neurorestorative effects. Applying molecular hydrogen, we measured blood glucose levels before and after middle cerebral artery occlusion (MCAO), 48-h cerebral oedema and infarct volumes, as well as 28-day weight, survival and neurological function. We also measured the levels of TLR4, NF-κB p65, phosphorylated NF-κB p65, catecholamines, acetylcholine and inflammatory factors. All measurements comprehensively showed the positive effect and translational advantage of molecular hydrogen on diabetic stroke. Molecular hydrogen improved the weight, survival and long-term neurological function of rats with diabetic stroke and alleviated changes in blood glucose levels before and after middle cerebral artery occlusion (MCAO), but no difference in circadian rhythm was observed. Molecular hydrogen inhibited the phosphorylation of NF-κB and significantly reduced inflammation. Molecular hydrogen mediates neurorestorative effects after stroke in diabetic rats. The effect is independent of circadian rhythms, indicating translational advantages. The molecular mechanism is related to the TLR4/NF-κB pathway and inflammation. Molecular hydrogen (H2) affects outcomes of ischemic stroke with diabetes mellitus (DM).

UHPLC-ESI-QE-Orbitrap-MS based metabolomics reveals the antioxidant mechanism of icaritin on mice with cerebral ischemic reperfusion

Background

Icaritin (ICT) has been previously demonstrated to display protective effects against cerebral ischemic reperfusion (I/R) by inhibiting oxidative stress, but the mechanism remains unclear. This study aimed to explore the mechanism from the perspective of metabolomics.

Methods

A mice cerebral artery occlusion/reperfusion (MCAO/R) model was explored to mimic cerebral ischemic reperfusion and protective effect of ICT was assessed by neurologic deficit scoring, infarct volume and brain water content. Ultra-high-performance liquid chromatography electrospray ionization orbitrap tandem mass spectrometry (UHPLC-ESI-QE-Orbitrap-MS) based metabolomic was performed to explore potential biomarkers. Brain tissue metabolic profiles were analyzed and metabolic biomarkers were identified through multivariate data analysis. The protein levels of Nrf2, HO-1 and HQO1 were assayed by western blot. The release of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) were detected using corresponding assay kits.

Results

The results showed that after ICT treatment, the neurological deficit, cerebral infarction area, brain edema and the level of MDA in brain tissue of MCAO/R mice were significantly reduced. Meanwhile, ICT enhanced the activity of SOD, CAT and GSH-Px. Western blot results confirmed that ICT up-regulated the protein levels of antioxidant-related protein including Nrf2, HO-1 and NQO1. According to the metabolomic profiling of brain tissues, clear separations were observed among the Sham, Model and ICT groups. A total of 44 biomarkers were identified, and the identified biomarkers were mainly related to linoleic acid metabolism, arachidonic acid metabolism, alanine, aspartate and glutamate metabolism, arginine biosynthesis, arginine and proline metabolism, D-glutamine and D-glutamate metabolism, taurine and hypotaurine metabolism and purine metabolism, respectively. At the same time, the inhibitory effect of ICT on arachidonic acid and linoleic acid in brain tissue, as well as the promoting effect on taurine, GABA, NAAG, may be the key factors for the anti-neurooxidative function of mice after MCAO/R injury.

Conclusion

Our results demonstrate that ICT has benefits for MCAO/R injury, which are partially related to the suppression of oxidative stress via stimulating the Nrf2 signaling and regulating the production of arachidonic acid, linoleic acid, taurine, GABA, NAAG in brain tissue.

Alterations in Plasma Lipidomic Profiles in Adult Patients with Schizophrenia and Major Depressive Disorder

Background and Objectives: Lipidomics is a pivotal tool for investigating the pathogenesis of mental disorders. However, studies qualitatively and quantitatively analyzing peripheral lipids in adult patients with schizophrenia (SCZ) and major depressive disorder (MDD) are limited. Moreover, there are no studies comparing the lipid profiles in these patient populations. Materials and Method: Lipidomic data for plasma samples from sex- and age-matched patients with SCZ or MDD and healthy controls (HC) were obtained and analyzed by liquid chromatography-mass spectrometry (LC-MS). Results: We observed changes in lipid composition in patients with MDD and SCZ, with more significant alterations in those with SCZ. In addition, a potential diagnostic panel comprising 103 lipid species and another diagnostic panel comprising 111 lipid species could distinguish SCZ from HC (AUC = 0.953) or SCZ from MDD (AUC = 0.920) were identified, respectively. Conclusions: This study provides an increased understanding of dysfunctional lipid composition in the plasma of adult patients with SCZ or MDD, which may lay the foundation for identifying novel clinical diagnostic methods for these disorders.

Molecular Hydrogen Neuroprotection in Post-Ischemic Neurodegeneration in the Form of Alzheimer's Disease Proteinopathy: Underlying Mechanisms and Potential for Clinical Implementation-Fantasy or Reality?

Currently, there is a lot of public interest in naturally occurring substances with medicinal properties that are minimally toxic, readily available and have an impact on health. Over the past decade, molecular hydrogen has gained the attention of both preclinical and clinical researchers. The death of pyramidal neurons in especially the CA1 area of the hippocampus, increased permeability of the blood-brain barrier, neuroinflammation, amyloid accumulation, tau protein dysfunction, brain atrophy, cognitive deficits and dementia are considered an integral part of the phenomena occurring during brain neurodegeneration after ischemia. This review focuses on assessing the current state of knowledge about the neuroprotective effects of molecular hydrogen following ischemic brain injury. Recent studies in animal models of focal or global cerebral ischemia and cerebral ischemia in humans suggest that hydrogen has pleiotropic neuroprotective properties. One potential mechanism explaining some of the general health benefits of using hydrogen is that it may prevent aging-related changes in cellular proteins such as amyloid and tau protein. We also present evidence that, following ischemia, hydrogen improves cognitive and neurological deficits and prevents or delays the onset of neurodegenerative changes in the brain. The available evidence suggests that molecular hydrogen has neuroprotective properties and may be a new therapeutic agent in the treatment of neurodegenerative diseases such as neurodegeneration following cerebral ischemia with progressive dementia. We also present the experimental and clinical evidence for the efficacy and safety of hydrogen use after cerebral ischemia. The therapeutic benefits of gas therapy open up new promising directions in breaking the translational barrier in the treatment of ischemic stroke.

Potential Therapeutic Effects of Mi-Jian-Chang-Pu Decoction on Neurochemical and Metabolic Changes of Cerebral Ischemia-Reperfusion Injury in Rats

As a traditional Chinese medicine formula, Mi-Jian-Chang-Pu decoction (MJCPD) has been successfully used in patients with language dysfunction and hemiplegia after ischemic stroke (IS). Given the excellent protective effects of MJCPD against nerve damage caused by IS in clinical settings, the present investigation mainly focused on its underlying mechanism on ischemia-reperfusion (IR) injury. Firstly, by applying the MCAO-induced cerebral IR injury rats, the efficacy of MJCPD on IS was estimated using the neurological deficit score, TTC, HE, and IHC staining, and neurochemical measurements. Secondly, an UHPLC-QTOF-MS/MS-based nontargeted metabolomics was developed to elucidate the characteristic metabolites. MJCPD groups showed significant improvements in the neurological score, infarction volume, and histomorphology, and the changes of GSH, GSSG, GSH-PX, GSSG/GSH, LDH, L-LA, IL-6, TNF-α, and VEGF-c were also reversed to normal levels after the intervention compared to the MCAO model group. Metabolomics profiling identified 21 different metabolites in the model group vs. the sham group, 10 of which were significantly recovered after treatment of MJCPD, and those 10 metabolites were all related to the oxidative stress process including glucose, fatty acid, amino acid, glutamine, and phospholipid metabolisms. Therefore, MJCPD might protect against IS by inhibiting oxidative stress during IR.

Different effects of hydrogen-rich water intake and hydrogen gas inhalation on gut microbiome and plasma metabolites of rats in health status

The potential for preventive and therapeutic applications of H₂ have now been confirmed in various disease. However, the effects of H₂ on health status have not been fully elucidated. Our previous study reported changes in the body weight and 13 serum biochemical parameters during the six-month hydrogen intervention. To obtain a more comprehensive understanding of the effects of long-term hydrogen consumption, the plasma metabolome and gut microbiota were investigated in this study. Compared with the control group, 14 and 10 differential metabolites (DMs) were identified in hydrogen-rich water (HRW) and hydrogen inhalation (HI) group, respectively. Pathway enrichment analysis showed that HRW intake mainly affected starch and sucrose metabolism, and DMs in HI group were mainly enriched in arginine biosynthesis. 16S rRNA gene sequencing showed that HRW intake induced significant changes in the structure of gut microbiota, while no marked bacterial community differences was observed in HI group. HRW intake mainly induced significant increase in the abundance of Lactobacillus, Ruminococcus, Clostridium XI, and decrease in Bacteroides. HI mainly induced decreased abundances of Blautia and Paraprevotella. The metabolic function was determined by metabolic cage analysis and showed that HI decreased the voluntary intake and excretions of rats, while HRW intake did not. The results of this study provide basic data for further research on hydrogen medicine. Determination of the effects of hydrogen intervention on microbiota profiles could also shed light on identification of mechanism underlying the biological effects of molecular hydrogen.

Hydroxysafflor yellow A and anhydrosafflor yellow B alleviate ferroptosis and parthanatos in PC12 cells injured by OGD/R

Ferroptosis and parthanatos are two types of programmed cell death associated with cerebral ischemia. There is a sizeable interest in seeking chemical components for the regulation of ferroptosis and parthanatos. Hydroxysafflor yellow A (HSYA) and anhydrosafflor yellow B (AHSYB) mitigated cell death caused by oxidative stress due to antioxidant capacity, yet the mechanism is still uncertain. Thus, we investigated whether HSYA and AHSYB prevent death through these two pathways with the aim to elucidate their potential protective mechanisms of cerebral ischemia. In this study, oxidative stress model was established by treating PC12 cells with oxygen glucose deprivation and reperfusion (OGD/R). Cellular functions and signaling pathways were analyzed in PC12 cells using cell counting kit-8 (CCK-8), flow cytometry, ELISA, iron assay kit, transmission electron microscopy (TEM), immunofluorescence, and western blot analysis. And the research proved HSYA and AHSYB protected cells from oxidative stress. The phenomenon is associated with ferroptosis and parthanatos. HSYA and AHSYB upregulated cystine/glutamate antiporter system x_c^- (system x_c^-) and glutathione peroxidase 4 (GPX4), returned the levels of GSH/GSSG ratio, reactive oxygen species (ROS) and iron ion, as well as alleviated lipid peroxidation. By reason of reducing ROS, HSYA and AHSYB restrained poly(ADP-ribose) polymerase-1 (PARP-1) overactivation, reduced the production of excess poly(ADP-ribose) (PAR) polymer and apoptosis inducing factor (AIF) nuclear translocation. The results suggested that HSYA and AHSYB limited ferroptosis and parthanatos to alleviate oxidative stress in PC12 cells. These findings may have implications for improving understanding of how drugs reduce oxidative stress and develop new strategies for treating degenerative diseases such as cerebral ischemia.

Phenylacetylglutamine, a Novel Biomarker in Acute Ischemic Stroke

Background: To discover novel metabolic biomarkers of ischemic stroke (IS), we carried out a two-stage metabolomic profiling of IS patients and healthy controls using untargeted and targeted metabolomic approaches.

Methods: We applied untargeted liquid chromatography-mass spectrometry (LC-MS) to detect the plasma metabolomic profiles of 150 acute IS patients and 50 healthy controls. The candidate differential microbiota-derived metabolite phenylacetylglutamine (PAGln) was validated in 751 patients with IS and 200 healthy controls. We evaluated the associations between PAGln levels and the severity and functional outcomes of patients with IS. Clinical mild stroke was defined as the National Institutes of Health Stroke Scale (NIHSS) score 0–5, and moderate-severe stroke as NIHSS score >5. A favorable outcome at 3 months after IS was defined as the modified Rankin Scale (mRS) score 0–2, and unfavorable outcome as mRS score 3–6.

Results: In untargeted metabolomic analysis, we detected 120 differential metabolites between patients with IS and healthy controls. Significantly altered metabolic pathways were purine metabolism, TCA cycle, steroid hormone biosynthesis, and pantothenate and CoA biosynthesis. Elevated plasma PAGln levels in IS patients, compared with healthy controls, were observed in untargeted LC-MS analysis and confirmed by targeted quantification (median 2.0 vs. 1.0 μmol/L; p < 0.001). Patients with moderate-severe stroke symptoms and unfavorable short-term outcomes also had higher levels of PAGln both in discovery and validation stage. After adjusting for potential confounders, high PAGln levels were independently associated with IS (OR = 3.183, 95% CI 1.671–6.066 for the middle tertile and OR = 9.362, 95% CI 3.797–23.083 for the highest tertile, compared with the lowest tertile) and the risk of unfavorable short-term outcomes (OR = 2.286, 95% CI 1.188–4.401 for the highest tertile).

Conclusions: IS patients had higher plasma levels of PAGln than healthy controls. PAGln might be a potential biomarker for IS and unfavorable functional outcomes in patients with IS.

Nuciferine attenuates acute ischemic stroke in a rat model: a metabolomic approach for the mechanistic study

Nuciferine is a promise therapeutic candidate for ischemic stroke. 1H NMR metabolomics was conducted in this study to further elucidate its pharmacological mechanism, which is helpful to be used as a potential treatment for stroke clinically.

Application of Metabolomics to the Discovery of Biomarkers for Ischemic Stroke in the Murine Model: a Comparison with the Clinical Results

Ischemic stroke (IS) is a major cause of mortality and disability worldwide. However, the pathogenesis of IS remains unknown, and methods for early prediction and diagnosis of IS are lacking. Metabolomics can be applied to biomarker discovery and mechanism exploration of IS by exploring metabolic alterations. In this review, 62 IS metabolomics studies in the murine model published from January 2006 to December 2020 in the PubMed and Web of Science databases were systematically reviewed. Twenty metabolites (e.g., lysine, phenylalanine, methionine, tryptophan, leucine, lactate, serine, N-acetyl-aspartic acid, and glutathione) were reported consistently in more than two-third murine studies. The disturbance of metabolic pathways, such as arginine biosynthesis; alanine, aspartate and glutamate metabolism; aminoacyl-tRNA biosynthesis; and citrate cycle, may be implicated in the development of IS by influencing the biological processes such as energy failure, oxidative stress, apoptosis, and glutamate toxicity. The transient middle cerebral artery occlusion model and permanent middle cerebral artery occlusion model exhibit both common and distinct metabolic patterns. Furthermore, five metabolites (proline, serine, LysoPC (16:0), uric acid, glutamate) in the blood sample and 7 metabolic pathways (e.g., alanine, aspartate, and glutamate metabolism) are shared in animal and clinical studies. The potential biomarkers and related pathways of IS in the murine model may facilitate the biomarker discovery for early diagnosis of IS and the development of novel therapeutic targets.

Plasma Lysophosphatidylcholine and Lysophosphatidylethanolamine Levels Were Associated With the Therapeutic Response to Olanzapine in Female Antipsychotics-naïve First-episode Patients With Schizophrenia

Background: Accumulating studies have shown that the pathophysiology of schizophrenia may be associated with aberrant lysophospolipid metabolism in the early stage of brain development. Recent evidence demonstrates that antipsychotic medication can regulate the phospholipase activity. However, it remains unclear whether lysophospolipid is associated with the therapeutic response to antipsychotic medication in schizophrenia. This study aimed to investigate the influence of olanzapine monotherapy on lysophosphatidylcholine (LPC) and lysophosphatidylethanolamine (LPE) and the association between symptom improvement and changes of LPC and LPE levels during treatment in antipsychotic-naïve first-episode (ANFE) patients.

Materials and Methods: The psychotic symptoms were evaluated by the Positive and Negative Syndrome Scale (PANSS). 25 ANFE patients were treated with olanzapine for 1 mo. The levels of LPC and LPE were determined and psychotic symptoms were assessed at baseline and at 1-mo follow-up.

Results: Relative to baseline, the psychotic symptoms were significantly reduced after olanzapine treatment, except for negative symptoms. Moreover, the levels of most LPC and LPE increased after treatment. Interestingly, increased LPC(18:3) and LPC(20:2) levels were positively associated with the reduction rates of PANSS positive subscore. In addition, baseline levels of LPE(20:5), LPE(18:3) and LPE(22:5) were predictors for the reduction of positive symptoms.

Conclusion: Our study reveals that the levels of lysophospolipid are associated with the improvement of positive symptoms, indicating that LPC may be a potential therapeutic target for olanzapine in schizophrenia. Moreover, baseline LPE levels were predictive biomarkers for the therapeutic response to olanzapine in the early stage of treatment in ANFE patients.

Hydrogen gas post-conditioning alleviates cognitive dysfunction and anxiety-like behavior in a rat model of subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) results in high rates of mortality and lasting disability. Hydrogen gas (H2) is an antioxidant with demonstrated neuroprotective efficacy. The present study examined the therapeutic efficacy of H2 inhalation on early brain injury following experimental SAH in rats and the potential underlying molecular mechanisms. The rats were randomly separated into three groups (n=36 per group): Sham, SAH and SAH + H2. Endovascular perforation of the right internal carotid artery was used to establish SAH. After perforation, rats in the SAH + H2 group inhaled 2.9% H2 with regular oxygen for 2 h. Then, 24 h post-SAH, TUNEL staining was used to detect apoptotic neurons, and both immunostaining and western blotting were conducted to examine changes in p38 MAPK activity and the expression levels of apoptotic regulators (Bcl-2, Bax and cleaved caspase-3) in the ventromedial prefrontal cortex. Then, 30 day post-SAH, Nissl staining was performed to detect neuronal injury, brain MRI was conducted to detect gross changes in brain structure and metabolism, the open field test was used to assess anxiety and the novel object recognition test was performed to assess memory. H2 inhalation following experimental SAH stabilized brain metabolites, improved recognition memory and reduced anxiety-like behavior, the neuronal apoptosis rate, phosphorylated p38 MAPK expression, cleaved caspase-3 expression and the Bax/Bcl-2 ratio. Collectively, the present results suggested that H2 inhalation can alleviate SAH-induced cognitive impairment, behavioral abnormalities and neuronal apoptosis in rats, possibly via inhibition of the p38 MAPK signal pathway.

Hydrogen gas post-conditioning attenuates early neuronal pyroptosis in a rat model of subarachnoid hemorrhage through the mitoKATP signaling pathway

Neuronal pyroptosis serves an important role in the progress of neurologic dysfunction following subarachnoid hemorrhage (SAH), which is predominantly caused by a ruptured aneurysm. Hydrogen gas has been previously reported to be an effective anti-inflammatory agent against ischemia-associated diseases by regulating mitochondrial function. The objective of the present study was to investigate the potential neuroprotective effects of hydrogen gas post-conditioning against neuronal pyroptosis after SAH, with specific focus on the mitochondrial ATP-sensitive K⁺ (mitoK_ATP) channels. Following SAH induction by endovascular perforation, rats were treated with inhalation of 2.9% hydrogen gas for 2 h post-perforation. Neurologic deficits, brain water content, reactive oxygen species (ROS) levels, neuronal pyroptosis, phosphorylation of ERK1/2, p38 MAPK and pyroptosis-associated proteins IL-1β and IL-18 were evaluated 24 h after perforation by a modified Garcia method, ratio of wet/dry weight, 2',7'-dichlorofluorescin diacetate, immunofluorescence and western blot assays, respectively. An inhibitor of the mitoK_ATP channel, 5-hydroxydecanoate sodium (5-HD), was used to assess the potential role of the mitoK_ATP-ERK1/2-p38 MAPK signal pathway. Hydrogen gas post-conditioning significantly alleviated brain edema and improved neurologic function, reduced ROS production and neuronal pyroptosis, suppressed the expression of IL-1β and IL-18 whilst upregulating ERK1/2 phosphorylation, but downregulated p38 MAPK activation 24 h post-SAH. These aforementioned effects neuroprotective were partially reversed by 5-HD treatment. Therefore, these observations suggest that post-conditioning with hydrogen gas ameliorated SAH-induced neuronal pyroptosis at least in part through the mitoK_ATP/ERK1/2/p38 MAPK signaling pathway.

Mechanism of hydrogen on cervical cancer suppression revealed by high‑throughput RNA sequencing

Cervical cancer is considered one of the diseases with the highest mortality among women and with limited treatment options. Hydrogen (H₂) inhalation has been reported to have a variety of tumor-suppressive effects, but the exact mechanism remains unclear. In the present study, HeLa cervical cancer cells and HaCaT keratinocytes treated with H₂, and a HeLa xenograft mouse model subjected to H₂ inhalation were established. TUNEL, Cell Counting Kit-8 and Ki67 staining assays were used to detect cell apoptosis and proliferation. Oxidative stress was determined according to the levels of reactive oxygen species, malondialdehyde and superoxide dismutase. Tumor growth was recorded every 3 days, and the excised tumors were stained with hematoxylin and eosin. High-throughput RNA sequencing and subsequent Gene Ontology (GO) enrichment analysis were performed in HeLa-treated and un-treated HeLa cells. The expression of hypoxia-inducible factor (HIF)-1α and NF-κB p65 was verified by western blotting, immunohistochemistry and reverse transcription-quantitative PCR. The results revealed an increased apoptosis rate, and reduced cell proliferation and oxidative stress in H₂-treated HeLa cells but not in HaCaT cells. Similarly, decreased tumor growth and cell proliferation, and enhanced cell apoptosis were observed in H₂-treated HeLa tumors. RNA sequencing and GO analysis suggest that downregulated HIF1A (HIF-1α mRNA) and RelA (NF-κB p65) levels, and reduced NF-κB signaling were associated with the antitumor effect of H₂. Finally, decreased HIF-1α and NF-κB p65 expression both at the transcriptional and translational levels were observed in H₂-treated HeLa cells and in HeLa-derived tumors. In conclusion, the present study reveals a novel mechanism of H₂ against cervical cancer, which may serve as a potential therapeutic target in clinical practice.

Neuroprotective Effects of Danshen Chuanxiongqin Injection Against Ischemic Stroke: Metabolomic Insights by UHPLC-Q-Orbitrap HRMS Analysis

The incidence of cerebral ischemic stroke characterized by high mortality is increasing every year. Danshen Chuanxiongqin Injection (DSCXQ), a traditional Chinese medicine (TCM) preparation, is often applied to treat cerebral apoplexy and its related sequelae. However, there is a lack of systematic research on how DSCXQ mediates its protective effects against cerebral ischemia stroke. Metabolomic analysis based on UHPLC-Q-Orbitrap HRMS was employed to explore the potential mechanisms of DSCXQ on ischemic stroke induced by transient middle cerebral artery occlusion (MCAO). Pattern analysis and metabolomic profiling, combined by multivariate analysis disclosed that 55 differential metabolites were identified between Sham group and Model group, involving sphingolipid metabolism, glycerophospholipid metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, primary bile acid biosynthesis, pantothenate and CoA synthesis and valine, leucine and isoleucine biosynthesis pathways. DSCXQ could reverse brain metabolic deviations in stroke by significantly upregulating the levels of L-tryptophan, Lyso (18:0/0:0), LPC (18:2), Indole-3-methyl acetate, and downregulating the levels of sphinganine 1-phosphate, L-threonic acid, glutaconic acid and N6,N6,N6-Trimethyl-L-lysine. In our study, we focused on the neuroprotective effects of DSCXQ against neuroinflammatory responses and neuronal apoptosis on a stroke model based on sphingolipid metabolism. The expressions of Sphk1, S1PR1, CD62P, Bcl-2, Bax, and cleaved Caspase-3 in brain tissue were evaluated. The neurological deficit, cerebral infarct size and behavioral abnormality were estimated. Results showed that DSCXQ intervention significantly reduced cerebral infarct size, ameliorated behavioral abnormality, inhibited the expression of Sphk1, S1PR1, CD62P, Bax, Cleaved Caspase-3, while increased the level of Bcl-2, and prevented neuronal apoptosis. The limitations are that our study mainly focused on the verification of sphingolipid metabolism pathway in stroke, and while other metabolic pathways left unverified. Our study indicates that SphK1-SIP axis may potentiate neuroinflammatory responses and mediate brain damage through neuronal apoptosis, and DSCXQ could suppress the activity of SphK1-SIP axis to protect brain tissue in cerebral ischemia. In conclusion, this study facilitates our understanding of metabolic changes in ischemia stroke and the underlying mechanisms related to the clinical application of DSCXQ.

Screening of lipid metabolism biomarkers in patients with coronary heart disease via ultra-performance liquid chromatography-high resolution mass spectrometry

Coronary heart disease (CHD) has a high mortality worldwide. This study aimed to screen lipid metabolism biomarkers in patients with coronary heart disease via ultra-performance liquid chromatography-high resolution mass spectrometry. Extraction and reconstitution solvents, liquid chromatographic and mass spectrometry conditions were optimized to detect more plasma lipid metabolites. In this study, the chromatographic and mass spectra characteristics of lipid metabolites were summarized. A total of 316 lipid metabolites were annotated via diagnostic fragment ion filtration, nitrogen rule filtration, and neutral loss filtration. Glycerophospholipid metabolism and sphingolipid metabolism were revealed as the main lipid disorders of CHD. This study provides a novel insight for high-throughput detection of lipid metabolites in plasma and provides a further understanding of the occurrence of CHD, which can provide valuable suggestions for the prevention of CHD.

Neuroprotective Effects of Molecular Hydrogen: A Critical Review

Molecular hydrogen (H2) is a physiologically inert gas. However, during the last 10 years, increasing evidence has revealed its biological functions under pathological conditions. More specifically, H2 has protective effects against a variety of diseases, particularly nervous system disorders, which include ischemia/reperfusion injury, traumatic injury, subarachnoid hemorrhage, neuropathic pain, neurodegenerative diseases, cognitive dysfunction induced by surgery and anesthesia, anxiety, and depression. In addition, H2 plays protective roles mainly through anti-oxidation, anti-inflammation, anti-apoptosis, the regulation of autophagy, and preservation of mitochondrial function and the blood-brain barrier. Further, H2 is easy to use and has neuroprotective effects with no major side-effects, indicating that H2 administration is a potential therapeutic strategy in clinical settings. Here we summarize the H2 donors and their pharmacokinetics. Meanwhile, we review the effectiveness and safety of H2 in the treatment of various nervous system diseases based on preclinical and clinical studies, leading to the conclusion that H2 can be a simple and effective clinical therapy for CNS diseases such as ischemia-reperfusion brain injury, Parkinson's disease, and diseases characterized by cognitive dysfunction. The potential mechanisms involved in the neuroprotective effect of H2 are also analyzed.

Hippocampal Sector-Specific Metabolic Profiles Reflect Endogenous Strategy for Ischemia-Reperfusion Insult Resistance

The gerbil is a well-known model for studying cerebral ischemia. The CA1 of the hippocampus is vulnerable to 5 min of ischemia, while the CA2–4 and dentate gyrus (DG) are resistant to it. Short-lasting ischemia, a model of transient ischemic attacks in men, results in CA1 neuron death within 2–4 days of reperfusion. Untargeted metabolomics, using LC-QTOF-MS, was used to enrich the knowledge about intrinsic vulnerability and resistance of hippocampal regions and their early post-ischemic response (IR). In total, 30 significant metabolites were detected. In controls, taurine was significantly lower and guanosine monophosphate was higher in CA1, as compared to that in CA2–4,DG. LysoPG and LysoPE were more abundant in CA1, while LysoPI 18:0 was detected only in CA2–4,DG. After IR, a substantial decrease in the citric acid level in CA1, an accumulation of pipecolic acid in both regions, and opposite changes in the amount of PE and LysoPE were observed. The following metabolic pathways were identified as being differentially active in control CA1 vs. CA2–4,DG: metabolism of taurine and hypotaurine, glycerophospholipid, and purine. These results may indicate that a regulation of cell volume, altered structure of cell membranes, and energy metabolism differentiate hippocampal regions. Early post-ischemia, spatial differences in the metabolism of aminoacyl-tRNA biosynthesis, and amino acids and their metabolites with a predominance of those which upkeep their well-being in CA2–4,DG are shown. Presented results are consistent with genetic, morphological, and functional data, which may be useful in further study on endogenous mechanisms of neuroprotection and search for new targets for therapeutic interventions.

Metabolomics Research Conducted by Nurse Scientists: A Systematic Scoping Review

Metabolomics, one of the newest omics, allows for investigation of holistic responses of living systems to myriad biological, behavioral, and environmental factors. Researcher use metabolomics to examine the underlying mechanisms of clinically observed phenotypes. However, these methods are complex, potentially impeding their uptake by scientists. In this scoping review, we summarize literature illustrating nurse scientists' use of metabolomics. Using electronic search methods, we identified metabolomics investigations conducted by nurse scientists and published in English-language journals between 1990 and November 2019. Of the studies included in the review (N = 30), 9 (30%) listed first and/or senior authors that were nurses. Studies were conducted predominantly in the United States and focused on a wide array of clinical conditions across the life span. The upward trend we note in the use of these methods by nurse scientists over the past 2 decades mirrors a similar trend across scientists of all backgrounds. A broad range of study designs were represented in the literature we reviewed, with the majority involving untargeted metabolomics (n = 16, 53.3%) used to generate hypotheses (n = 13, 76.7%) of potential metabolites and/or metabolic pathways as mechanisms of clinical conditions. Metabolomics methods match well with the unique perspective of nurse researchers, who seek to integrate the experiences of individuals to develop a scientific basis for clinical practice that emphasizes personalized approaches. Although small in number, metabolomics investigations by nurse scientists can serve as the foundation for robust programs of research to answer essential questions for nursing.

Protective Effects of Oroxylin A on Oxygen-Glucose Deprivation/Reperfusion-Induced PC12 Cells by Activating the Sonic Hedgehog Signal Pathway

Ischemic stroke is a leading cause of human death. The injury that is induced by oxygen-glucose deprivation/reperfusion in stroke remains unsolved. This study first investigated the effects of oroxylin A on oxygen-glucose deprivation/reperfusion-induced PC12 cells. This was performed by dividing the cells into a control group, an oxygen-glucose deprivation and reperfusion (OGD/R) group, a solvent control group, and experimental groups treated with different concentrations of oroxylin A. Cell viability was evaluated by Cell Counting Kit-8 assay. Relevant indicators of oxidant stress were detected by using the appropriate kits. Western blot was applied to detect the expressions of inflammatory cytokine and proteins of the signaling pathway. Oroxylin A pretreatment exerted anti-oxidative, anti-apoptotic, and anti-inflammatory effects in oxygen-glucose deprivation/reperfusion-induced PC12 cells, thus indicating it as a new avenue for stroke treatment and providing references for future studies.