The role of protein glycosylation in the occurrence and outcome of acute ischemic stroke

Lactylation and Ischemic Stroke: Research Progress and Potential Relationship

Ischemic stroke is caused by interrupted cerebral blood flow and is a leading cause of mortality and disability worldwide. Significant advancements have been achieved in comprehending the pathophysiology of stroke and the fundamental mechanisms responsible for ischemic damage. Lactylation, as a newly discovered post-translational modification, has been reported to participate in several physiological and pathological processes. However, research on lactylation and ischemic stroke is scarce. This review summarized the current function of protein lactylation in other diseases or normal physiological processes and explored their potential link with the pathophysiological process and the reparative mechanism of ischemic stroke. We proposed that neuroinflammation, regulation of metabolism, regulation of messenger RNA translation, angiogenesis, and neurogenesis might be the bridge linking lactylation and ischemic stroke. Our study provided a novel perspective for comprehending the role of protein lactylation in the pathophysiological processes underlying ischemic stroke. Lactylation might be a promising target in drug development of ischemic stroke.

SLC35A2-mediated bisected GlcNAc-modified extracellular vesicles enhance immune regulation in breast cancer lung metastasis

This study investigates the role of SLC35A2-mediated bisected GlcNAc-modified small extracellular vesicles (sEVs) in breast cancer (BC) lung metastasis. By modulating B3GALT1 expression, these sEVs regulate the pre-metastatic immune microenvironment, enhancing CD8+ T cell infiltration and reducing immune evasion. The use of β-peptide-loaded sEVs further amplifies anti-metastatic effects, as demonstrated in vivo mouse models and molecular analyses. These findings underscore the therapeutic potential of glycosylation-modified sEVs in enhancing immune responses and controlling BC metastasis.

Expression of Serum Inflammatory Factors in Patients with Acute Ischemic Stroke Complicated with Type 2 Diabetes Mellitus and Its Relationship with the Formation and Stability of Carotid Atherosclerotic Plaque

To explore the stability of carotid plaques and their relationship with biomarkers in patients with acute ischemic stroke (AIS) complicated with type 2 diabetes mellitus (T2DM). A retrospective analysis was conducted on 160 cases of AIS patients with T2DM. They were divided into plaque group, intima thickening group (CG), and normal intima group (DG). 95 plaque patients were grouped: stable plaque group (AG) and unstable plaque group (BG). Serum indicators and carotid intima-media thickness (IMT) were collated, and Pearson correlation analysis (PCA) and multiple logistic regression analysis (MLRA) were performed. As against CG, AG and BG had higher levels of high-sensitivity C-reactive protein (hs-CRP), homocysteine (HCY), and IMT (P < 0.05). The carotid IMT in patients suggested an obvious positive correlation with hs-CRP and HCY (P < 0.001). Hs-CRP and HCY had an obvious positive impact on the formation of carotid plaques; as against AG, BG had higher levels of hs-CRP, HCY, total cholesterol (TC), and IMT (P < 0.05). The stability of patients' carotid arteries suggested an obvious positive correlation with hs-CRP and TC (P < 0.05), and HCY (P < 0.001). The levels of hs-CRP, TC, and HCY had an obvious positive impact on the IMT of patients (P < 0.05). High levels of hs-CRP, TC, and HCY have a positive impact on the stability of carotid plaques and are independent risk factors for plaque instability.

Altered Pattern of Serum N-Glycome in Subarachnoid Hemorrhage and Cerebral Vasospasm

Background: Subarachnoid hemorrhage is a serious condition caused by ruptured intracranial aneurysms, resulting in severe disability mainly in young adults. Cerebral vasospasm is one of the most common complication of subarachnoid hemorrhage; thus, active prevention is key to improve the prognosis. The glycosylation of proteins is a critical quality attribute which is reportedly altered in patients diagnosed with acute ischemic stroke. In this study, we examined the N-glycosylation profile of serum glycoproteins in patients with subarachnoid hemorrhage without vasospasm compared to patients with vasospasm. Methods: The serum N-glycans were released by PNGase F (Peptide: N-glycosidase F) digestion and subsequently labeled by procainamide via reductive amination. The samples were analyzed by hydrophilic-interaction liquid chromatography after solid-phase extraction-based sample purification. Results: Besides the glycosylation pattern, we also investigated the biomarkers following subarachnoid hemorrhage. Multiple statistical analyses were performed in order to find significant differences and identify potential prediction factors of cerebral vasospasm. Significant differences were identified such as higher sialylation on bi-, tri-, and tetra-antennary structures in patients with subarachnoid hemorrhage and cerebral vasospasm. Conclusions: Our results suggest that glycosylation analysis can improve the identification of patients with cerebral vasospasm in combination with laboratory parameters.

Unraveling the protein post-translational modification landscape: Neuroinflammation and neuronal death after stroke

The impact of stroke on global health is profound, with both high mortality and morbidity rates. This condition can result from cerebral ischemia, intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH). The pathophysiology of stroke involves secondary damage and irreversible loss of neuronal function. Post-translational modifications (PTMs) have been recognized as crucial regulatory mechanisms in ischemic and hemorrhagic stroke-induced brain injury. These PTMs include phosphorylation, glycosylation, ubiquitination, SUMOylation, acetylation, and succinylation. This comprehensive review delves into recent research on the PTMs landscape associated with neuroinflammation and neuronal death specific to cerebral ischemia, ICH, and SAH. This review aims to explain the role of PTMs in regulating pathologic mechanisms and present critical techniques and proteomic strategies for identifying PTMs. This knowledge helps us comprehend the underlying mechanisms of stroke injury and repair processes, leading to the development of innovative treatment strategies. Importantly, this review underscores the significance of exploring PTMs to understand the pathophysiology of stroke.

The Prognosis of Neutrophil-to-Lymphocyte Ratio and Lymphocyte-to-Monocyte Ratio in Elderly with Acute Ischemic Stroke

Background

Neutrophil-to-lymphocyte ratio (NLR) and Lymphocyte-to-monocyte ratio (LMR) have been reported to be associated with outcomes in acute ischemic stroke. However, research on elderly populations remains relatively scarce. We investigated the prognosis of NLR and LMR in elderly with acute ischemic stroke(AIS).

Methods

Based on the modified Rankin Score (mRS) on the 90th day after stroke, patients were divided into group and bad prognosis groups. Multivariate logistic regression analysis and receiver operating curves were used to identify prognostic factors and their predictive powers.

Results

In total, 824 elderly patients with AIS were enrolled between November 2021 and December 2023. Significant differences emerged in the NLR, LMR, and lymphocyte count between the two groups (P<0.05). Binary logistic regression identified NLR, LMR and neutrophil count as independent risk factors for an unfavorable prognosis in elderly patients with AIS. The areas under the curve (AUCs) of NLR, LMR, and the combination of NLR and LMR to discriminate poor function prognosis were 0.703, 0.672, and 0.706, respectively. ROC analysis also showed that combination of NLR and LMR was superior to NLR and LMR alone for predicting AIS.

Conclusion

NLR and LMR independently contribute to an unfavorable prognosis in elderly patients with AIS. The area under the ROC curve (AUC) for the combined NLR and LMR was higher than that for NLR and LMR individually, suggesting that combining these two indicators can improve the predictive ability for clinical outcomes in elderly patients with AIS.

Patent highlights October-November 2023

A snapshot of noteworthy recent developments in the patent literature of relevance to pharmaceutical and medical research and development.

β-1,4-Galactosyltransferase 1 protects against cerebral ischemia injury in mice by suppressing ferroptosis via the TAZ/Nrf2/HO-1 signaling pathway

BACKGROUND

Ischemic stroke leads a primary cause of mortality in human diseases, with a high disability rate worldwide. This study aims to investigate the function of β-1,4-galactosyltransferase 1 (B4galt1) in mouse brain ischemia/reperfusion (I/R) injury.

METHODS

Recombinant human B4galt1 (rh-B4galt1) was intranasally administered to the mice model of middle cerebral artery occlusion (MCAO)/reperfusion. In this study, the impact of rh-B4galt1 on cerebral injury assessed using multiple methods, including the neurological disability status scale, 2,3,5-triphenyltetrazolium chloride (TTC), Nissl and TUNEL staining. This study utilized laser speckle Doppler flowmeter to monitor the cerebral blood flow. Western blotting was performed to assess the protein expression levels, and fluorescence-labeled dihydroethidium method was performed to determine the superoxide anion generation. Assay kits were used for the measurement of iron, malondialdehyde (MDA) and glutathione (GSH) levels.

RESULTS

We demonstrated that rh-B4galt1 markedly improved neurological function, reduced cerebral infarct volume and preserved the completeness of blood-brain barrier (BBB) for preventing damage. These findings further illustrated that rh-B4galt1 alleviated oxidative stress, lipid peroxidation, as well as iron deposition induced by I/R. The vital role of ferroptosis was proved in brain injury. Furthermore, the rh-B4galt1 could increase the levels of TAZ, Nrf2 and HO-1 after I/R. And TAZ-siRNA and ML385 reversed the neuroprotective effects of rh-B4galt1.

CONCLUSIONS

The results indicated that rh-B4galt1 implements neuroprotective effects by modulating ferroptosis, primarily via upregulating TAZ/Nrf2/HO-1 pathway. Thus, B4galt1 could be seen as a promising novel objective for ischemic stroke therapy.

Correlation analysis of inflammatory markers with the short-term prognosis of acute ischaemic stroke

Stroke is the second leading cause of death worldwide, and China has the highest stroke incidence in the world. The systemic inflammatory response index (SIRI), systemic inflammatory response index (SIRI), systemic immune-inflammatory index (SII), neutrophil-to-high-density lipoprotein ratio (NHR), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and monocyte-to-lymphocyte ratio (MLR) have clinical in predicting the prognosis of acute ischaemic stroke (AIS) patients. No studies have compared the predictive value of these six composite inflammatory markers. This study included 516 AIS patients with AIS symptoms for < 24 h. The short-term prognosis of AIS patients at 30 days was assessed using the modified Rankin scale (mRS), an mRS score > 2 defining poor prognosis. The results of the univariate analysis showed that all six composite inflammatory indices, SIRI, SII, NHR, NLR, PLR and MLR, were associated with a poor prognosis in patients with AIS. All six composite inflammatory indicators correlated with the short-term prognosis of AIS patients. The six composite inflammation indicators were included in the binary logistic regression, and the results showed that SIRI, NLR and PLR were found to be independent risk factors for poor short-term prognosis in AIS patients. Among the six inflammatory markers, SIRI, NLR and PLR were the most clinically valuable for predicting the short-term prognosis of patients with AIS. Peripheral blood indices are easy to obtain clinically and can provide important clinical value for early prognosis and treatment adjustment.

Body fluids biomarkers associated with prognosis of acute ischemic stroke: progress and prospects

Acute ischemic stroke (AIS) is one of the most common strokes posing a grave threat to human life and health. Predicting the prognosis of AIS allows for an understanding of disease progress, and a better quality of life by making individualized treatment scheme. In this paper, we conducted a systematic search on PubMed, focusing on the relevant literature in the last 5 years. Summarizing the candidate prognostic biomarkers of AIS in body fluids such as blood, urine, saliva and cerebrospinal fluid is often of great significance for the management of acute ischemic stroke, which has the potential to facilitate early diagnosis, treatment, prevention and long-term outcome improvement.

Serum N-glycomic profiling identifies candidate biomarker panels for assessing coronary artery stenosis severity

Stenosis severity may escalate over the course of coronary artery disease (CAD), increasing the risk of death for the patient. Conventionally, the assessment of stenosis degree relies on invasive coronary angiography (ICA), an invasive examination unsuitable for patients in poor physical condition or those with contrast allergies and one that imposes a psychological burden on patients. Although abnormal serum N-glycan profiles have exhibited robust associations with various cardiovascular diseases, including CAD, their potential in diagnosing CAD stenosis remains to be determined. In this study, we performed a comprehensive analysis of serum N-glycome from 132 patients who underwent ICA and 27 healthy controls using MALDI-TOF-mass spectrometry. The patients who underwent ICA examination were categorized into four groups based on stenosis severity: no/mild/moderate/severe stenosis. Twenty-seven N-glycans were directly quantified, and 47 derived glycan traits were obtained. Notably, among these 74 glycan features, 18 exhibited variations across the study groups. Using a combination of least absolute shrinkage and selection operator and logistic regression analyses, we developed five diagnostic models for recognizing stenosis degree. Our results suggested that alterations in serum N-glycosylation modifications might be valuable for identifying stenosis degree and monitoring disease progression in individuals with CAD. It is expected to offer a noninvasive alternative for those who could not undergo ICA because of various reasons. However, the diagnostic potential of serum N-glycan panels as biomarkers requires multicenter, large cohort validation in the future.

The effects of glycosylation modifications on monocyte recruitment and foam cell formation in atherosclerosis

The monocyte recruitment and foam cell formation have been intensively investigated in atherosclerosis. Nevertheless, as the study progressed, it was obvious that crucial molecules participated in the monocyte recruitment and the membrane proteins in macrophages exhibited substantial glycosylation modifications. These modifications can exert a significant influence on protein functions and may even impact the overall progression of diseases. This article provides a review of the effects of glycosylation modifications on monocyte recruitment and foam cell formation. By elaborating on these effects, we aim to understand the underlying mechanisms of atherogenesis further and to provide new insights into the future treatment of atherosclerosis.

Glycosylation: A new signaling paradigm for the neurovascular diseases

A wide range of life-threatening conditions with complicated pathogenesis involves neurovascular disorders encompassing Neurovascular unit (NVU) damage. The pathophysiology of NVU is characterized by several features including tissue hypoxia, stimulation of inflammatory and angiogenic processes, and the initiation of intricate molecular interactions, collectively leading to an elevation in blood-brain barrier permeability, atherosclerosis and ultimately, neurovascular diseases. The presence of compelling data about the significant involvement of the glycosylation in the development of diseases has sparked a discussion on whether the abnormal glycosylation may serve as a causal factor for neurovascular disorders, rather than being just recruited as a secondary player in regulating the critical events during the development processes like embryo growth and angiogenesis. An essential tool for both developing new anti-ischemic therapies and understanding the processes of ischemic brain damage is undertaking pre-clinical studies of neurovascular disorders. Together with the post-translational modification of proteins, the modulation of glycosylation and its enzymes implicates itself in several abnormal activities which are known to accelerate neuronal vasculopathy. Despite the failure of the majority of glycosylation-based preclinical and clinical studies over the past years, there is a significant probability to provide neuroprotection utilizing modern and advanced approaches to target abnormal glycosylation activity at embryonic stages as well. This article focuses on a variety of experimental evidence to postulate the interconnection between glycosylation and vascular disorders along with possible treatment options.