Human iPSC-derived glia models for the study of neuroinflammation

Neuroinflammation is a complex biological process that plays a significant role in various brain disorders. Microglia and astrocytes are the key cell types involved in inflammatory responses in the central nervous system. Neuroinflammation results in increased levels of secreted inflammatory factors, such as cytokines, chemokines, and reactive oxygen species. To model neuroinflammation in vitro, various human induced pluripotent stem cell (iPSC)-based models have been utilized, including monocultures, transfer of conditioned media between cell types, co-culturing multiple cell types, neural organoids, and xenotransplantation of cells into the mouse brain. To induce neuroinflammatory responses in vitro, several stimuli have been established that can induce responses in either microglia, astrocytes, or both. Here, we describe and critically evaluate the different types of iPSC models that can be used to study neuroinflammation and highlight how neuroinflammation has been induced and measured in these cultures.

Dilemmas in parenteral glucose delivery and approach to glucose monitoring and interpretation in the neonate

Glucose control continues to be challenging for intensivists, in particular in high-risk neonates. Many factors play a role in glucose regulation including intrinsic and extrinsic factors. Optimal targets for euglycemia are debatable with uncertain short and long-term effects. Glucose measurement technology has continued to advance over the past decade; unfortunately, the availability of these advanced devices outside of research continues to be problematic. Treatment approaches should be individualized depending on etiology, symptoms, and neonatal conditions. Glucose infusions should be titrated based upon variations in organ glucose uptake, co-morbidities and postnatal development. In this article we summarize the most common dilemmas encountered in the NICU: ranges for euglycemia, physiological differences, approach for glucose measurements, monitoring and best strategies to control parenteral glucose delivery.

Potassium homeostasis - Physiology and pharmacology in a clinical context

Membrane voltage controls the function of excitable cells and is mainly a consequence of the ratio between the extra- and intracellular potassium concentration. Potassium homeostasis is safeguarded by balancing the extra-/intracellular distribution and systemic elimination of potassium to the dietary potassium intake. These processes adjust the plasma potassium concentration between 3.5 and 4.5 mmol/L. Several genetic and acquired diseases but also pharmacological interventions cause dyskalemias that are associated with increased morbidity and mortality. The thresholds at which serum K+ not only associates but also causes increased mortality are hotly debated. We discuss physiologic, pathophysiologic, and pharmacologic aspects of potassium regulation and provide informative case vignettes. Our aim is to help clinicians, epidemiologists, and pharmacologists to understand the complexity of the potassium homeostasis in health and disease and to initiate appropriate treatment strategies in dyskalemic patients.

Patient-related risk factors and lifestyle factors for lumbar degenerative disc disease: a systematic review

OBJECTIVE

Back pain is a very widespread disease pattern and is one of the most frequent causes for consultation of a physician in general. In most cases, discogenic changes are the pathomorphological correlate of back pain. Numerous risk factors have been identified for these degenerative changes, but the influence and significance of the risk factors remain unclear, which was the aim of this systematic review.

METHODS

A systematic literature search of the commonly used Pubmed database was performed using specific MESH terms. Further selection of the included studies was performed according to the PRISMA scheme, taking into account scientific merit as well as the relation to the research question.

RESULTS

A total of 111 studies out of 1035 found were finally included in the literature search. 134 risk factors for disc degeneration and disc herniation were identified. These were divided into (1) patient-specific risk factors (n░=░34), (2) radiological risk factors (n░=░31), (3) lifestyle risk factors (n░=░6), (4) workplace-related risk factors (n░=░12), (5) genetic risk factors (n░=░50), and (6) other risk factors (n░=░1). Non-adjustable risk factors were age >50 years (OR 1.7/year), female gender (OR 1.41), family disposition (OR 4.0), comorbidities like atherosclerosis (OR 2.24), arthritic changes in other joints (OR 3.1) and history of injuries of the back (OR 3.1). Adjustable factors were elevated BMI (OR 2.77), comorbidities like hypertension (OR 1.25), dyslipidemia (OR 1.26) and diabetes mellitus (OR 6.8), as well as lifestyle habits like smoking (OR 3.8).

DISCUSSION

In summary, intervertebral disc degenerations and herniations represent multifactorial events whose risk factors can be partly influenced and partly not influenced. This systematic review highlights the current state of knowledge as a basis for creating patient-specific algorithms to calculate risk for the development or progression of degenerative disc changes and disc herniations.

ApoE-modified liposomes encapsulating resveratrol and salidroside alleviate manifestations of Alzheimer's disease in APP/PS-1 mice

OBJECTIVE

Alzheimer's disease (AD) is a neurodegenerative disease that is associated with aging and is influenced by both genetic and environmental factors. Several studies and clinical trials have demonstrated that resveratrol (Res) and salidroside (Sal) are not only biologically safe but also influence AD biomarker trajectories. However, their clinical applications have been quite limited due to poor specificity, low solubility, and insufficient blood-brain barrier (BBB) penetration. Therefore, we developed a nano-drug delivery system in which Res and Sal were encapsulated in liposomes, which were surface-modified with ApoE (ApoE-Res/Sal-Lips) to compensate for these deficiencies.

METHOD

In this study, ApoE-Res/Sal-Lips were prepared using a standard thin-film hydration method for liposomes. Then, cellular uptake of the loaded liposomes was assessed in vitro using fluorescent staining assays. A BBB model was constructed to investigate the capacity of the liposomes to cross the BBB in vitro, and the ability of liposomes to target the brain was observed by in vivo imaging. In addition, the neuroprotective effects of the different liposome formulations in APP/PS-1 mice were evaluated by measuring the changes in levels of oxidative, anti-inflammatory, and anti-apoptotic factors in the mice brains.

RESULTS

In vitro, ApoE-Res/Sal-Lips increased the uptake of Res and Sal by bEnd.3 and N2a cells, enhanced BBB penetration, and improved transport efficiency. In vivo, the ApoE-Res/Sal-Lips were found to alleviate AD pathological symptoms, reduce learning and memory impairments, and improve brain function.

CONCLUSION

ApoE-Res/Sal-Lips provide a new method for the treatment of AD.

Neuroprotective effects of meloxicam on transient brain ischemia in rats: the two faces of anti-inflammatory treatments

The inflammatory response plays an important role in neuroprotection and regeneration after ischemic insult. The use of non-steroidal anti-inflammatory drugs has been a matter of debate as to whether they have beneficial or detrimental effects. In this context, the effects of the anti-inflammatory agent meloxicam have been scarcely documented after stroke, but its ability to inhibit both cyclooxygenase isoforms (1 and 2) could be a promising strategy to modulate post-ischemic inflammation. This study analyzed the effect of meloxicam in a transient focal cerebral ischemia model in rats, measuring its neuroprotective effect after 48 hours and 7 days of reperfusion and the effects of the treatment on the glial scar and regenerative events such as the generation of new progenitors in the subventricular zone and axonal sprouting at the edge of the damaged area. We show that meloxicam's neuroprotective effects remained after 7 days of reperfusion even if its administration was restricted to the two first days after ischemia. Moreover, meloxicam treatment modulated glial scar reactivity, which matched with an increase in axonal sprouting. However, this treatment decreased the formation of neuronal progenitor cells. This study discusses the dual role of anti-inflammatory treatments after stroke and encourages the careful analysis of both the neuroprotective and the regenerative effects in preclinical studies.

Low-intensity pulsed ultrasound ameliorates glia-mediated inflammation and neuronal damage in experimental intracerebral hemorrhage conditions

BACKGROUND

Intracerebral hemorrhage (ICH) is a condition associated with high morbidity and mortality, and glia-mediated inflammation is a major contributor to neurological deficits. However, there is currently no proven effective treatment for clinical ICH. Recently, low-intensity pulsed ultrasound (LIPUS), a non-invasive method, has shown potential for neuroprotection in neurodegenerative diseases. This study aimed to investigate the neuroprotective effects and potential mechanisms of LIPUS on glia-mediated inflammation in ICH.

METHODS

This study used 289 mice to investigate the effects of LIPUS on ICH. ICH was induced by injecting bacterial collagenase (type VII-S; 0.0375 U) into the striatum of the mice. LIPUS was applied noninvasively for 3 days, including a 2-h-delayed intervention to mimic clinical usage. The study evaluated neurological function, histology, brain water content, hemoglobin content, MRI, and protein expression of neurotrophic factors, inflammatory molecules, and apoptosis. In vitro studies investigated glia-mediated inflammation by adding thrombin (10 U/mL) or conditioned media to primary and cell line cultures. The PI3K inhibitor LY294002 was used to confirm the effects of PI3K/Akt signaling after LIPUS treatment.

RESULTS

LIPUS treatment improved neurological deficits and reduced tissue loss, edema, and neurodegeneration after ICH. The protective effects of LIPUS resulted from decreased glia-mediated inflammation by inhibiting PI3K/Akt-NF-κB signaling, which reduced cytokine expression and attenuated microglial activation-induced neuronal damage in vitro.

CONCLUSIONS

LIPUS treatment improved neurological outcomes and reduced glia-mediated inflammation by inhibiting PI3K/Akt-NF-κB signaling after ICH. LIPUS may provide a non-invasive potential management strategy for ICH.

Does depression in mid-life predispose to greater cognitive decline in later life in the Whitehall II cohort?

BACKGROUND

Later-life depression appears to have different symptomatology and possibly underlying pathology to younger adults. Depression is linked to dementia but whether it is a risk factor or an early sign of dementia remains unclear. Neuroinflammation is increasingly recognised in both conditions.

AIMS

To investigate the link between depression, inflammation and dementia. We hypothesised that recurrent depression increases the rate of cognitive decline in older adults and that this effect is modified by anti-inflammatory medication.

METHODS

We used data from Whitehall II including cognitive test results and reliable measures to assess depression. Depression was defined as a self-reported diagnosis or a score of ≥20 on the CESD. The presence/absence of inflammatory illness was assessed using a standardised list of inflammatory conditions. Individuals with dementia, chronic neurological and psychotic conditions were excluded. Logistic and linear regression was used to examine the effect of depression on cognitive test performance and the effect of chronic inflammation.

LIMITATIONS

Lack of clinical diagnoses of depression.

RESULTS

There were 1063 individuals with and 2572 without depression. Depression did not affect deterioration in episodic memory, verbal fluency or the AH4 test at 15-year follow up. We found no evidence of an effect of anti-inflammatory medication. Depressed individuals had worse cross-sectional performance on the Mill Hill test and tests of abstract reasoning and verbal fluency at both baseline and 15-year follow-up.

CONCLUSIONS

Using a UK based study with a long follow-up interval we have shown that depression in individuals aged >50 is not associated with increased cognitive decline.

Brain Injury: Response to Injury Wound-Healing Mechanisms and Enlarged Perivascular Spaces in Obesity, Metabolic Syndrome, and Type 2 Diabetes Mellitus

Embryonic genetic mechanisms are present in the brain and ready to be placed into action upon cellular injury, termed the response to injury wound-healing (RTIWH) mechanism. When injured, regional brain endothelial cells initially undergo activation and dysfunction with initiation of hemostasis, inflammation (peripheral leukocytes, innate microglia, and perivascular macrophage cells), proliferation (astrogliosis), remodeling, repair, and resolution phases if the injurious stimuli are removed. In conditions wherein the injurious stimuli are chronic, as occurs in obesity, metabolic syndrome, and type 2 diabetes mellitus, this process does not undergo resolution and there is persistent RTIWH with remodeling. Indeed, the brain is unique, in that it utilizes its neuroglia: the microglia cell, along with peripheral inflammatory cells and its astroglia, instead of peripheral scar-forming fibrocytes/fibroblasts. The brain undergoes astrogliosis to form a gliosis scar instead of a fibrosis scar to protect the surrounding neuropil from regional parenchymal injury. One of the unique and evolving remodeling changes in the brain is the development of enlarged perivascular spaces (EPVSs), which is the focus of this brief review. EPVSs are important since they serve as a biomarker for cerebral small vessel disease and also represent an impairment of the effluxing glymphatic system that is important for the clearance of metabolic waste from the interstitial fluid to the cerebrospinal fluid, and disposal. Therefore, it is important to better understand how the RTIWH mechanism is involved in the development of EPVSs that are closely associated with and important to the development of premature and age-related cerebrovascular and neurodegenerative diseases with impaired cognition.

Peripheral origin exosomal microRNAs aggravate glymphatic system dysfunction in diabetic cognitive impairment

Cognitive dysfunction is one of the common central nervous systems (CNS) complications of diabetes mellitus, which seriously affects the quality of life of patients and results in a huge economic burden. The glymphatic system dysfunction mediated by aquaporin-4 (AQP4) loss or redistribution in perivascular astrocyte endfeet plays a crucial role in diabetes-induced cognitive impairment (DCI). However, the mechanism of AQP4 loss or redistribution in the diabetic states remains unclear. Accumulating evidence suggests that peripheral insulin resistance target tissues and CNS communication affect brain homeostasis and that exosomal miRNAs are key mediators. Glucose and lipid metabolism disorder is an important pathological feature of diabetes mellitus, and skeletal muscle, liver and adipose tissue are the key target insulin resistance organs. In this review, the changes in exosomal miRNAs induced by peripheral metabolism disorders in diabetes mellitus were systematically reviewed. We focused on exosomal miRNAs that could induce low AQP4 expression and redistribution in perivascular astrocyte endfeet, which could provide an interorgan communication pathway to illustrate the pathogenesis of DCI. Furthermore, the mechanisms of exosome secretion from peripheral insulin resistance target tissue and absorption to the CNS were summarized, which will be beneficial for proposing novel and feasible strategies to optimize DCI prevention and/or treatment in diabetic patients.

Synaptamide Ameliorates Hippocampal Neurodegeneration and Glial Activation in Mice with Traumatic Brain Injury

Traumatic brain injury (TBI) is a major concern for public health worldwide, affecting 55 million people and being the leading cause of death and disability. To improve the outcomes and effectiveness of treatment for these patients, we conducted a study on the potential therapeutic use of N-docosahexaenoylethanolamine (synaptamide) in mice using the weight-drop injury (WDI) TBI model. Our study focused on exploring synaptamide's effects on neurodegeneration processes and changes in neuronal and glial plasticity. Our findings showed that synaptamide could prevent TBI-associated working memory decline and neurodegenerative changes in the hippocampus, and it could alleviate decreased adult hippocampal neurogenesis. Furthermore, synaptamide regulated the production of astro- and microglial markers during TBI, promoting the anti-inflammatory transformation of the microglial phenotype. Additional effects of synaptamide in TBI include stimulating antioxidant and antiapoptotic defense, leading to the downregulation of the Bad pro-apoptotic marker. Our data suggest that synaptamide has promising potential as a therapeutic agent to prevent the long-term neurodegenerative consequences of TBI and improve the quality of life.

Injectable hydrogels in central nervous system: Unique and novel platforms for promoting extracellular matrix remodeling and tissue engineering

Repairing central nervous system (CNS) is difficult due to the inability of neurons to recover after damage. A clinically acceptable treatment to promote CNS functional recovery and regeneration is currently unavailable. According to recent studies, injectable hydrogels as biodegradable scaffolds for CNS tissue engineering and regeneration have exceptionally desirable attributes. Hydrogel has a biomimetic structure similar to extracellular matrix, hence has been considered a 3D scaffold for CNS regeneration. An interesting new type of hydrogel, injectable hydrogels, can be injected into target areas with little invasiveness and imitate several aspects of CNS. Injectable hydrogels are being researched as therapeutic agents because they may imitate numerous properties of CNS tissues and hence reduce subsequent injury and regenerate neural tissue. Because of their less adverse effects and cost, easier use and implantation with less pain, and faster regeneration capacity, injectable hydrogels, are more desirable than non-injectable hydrogels. This article discusses the pathophysiology of CNS and the use of several kinds of injectable hydrogels for brain and spinal cord tissue engineering, paying particular emphasis to recent experimental studies.

Machine Learning Assisting the Prediction of Clinical Outcomes following Nucleoplasty for Lumbar Degenerative Disc Disease

BACKGROUND

Lumbar degenerative disc disease (LDDD) is a leading cause of chronic lower back pain; however, a lack of clear diagnostic criteria and solid LDDD interventional therapies have made predicting the benefits of therapeutic strategies challenging. Our goal is to develop machine learning (ML)-based radiomic models based on pre-treatment imaging for predicting the outcomes of lumbar nucleoplasty (LNP), which is one of the interventional therapies for LDDD.

METHODS

The input data included general patient characteristics, perioperative medical and surgical details, and pre-operative magnetic resonance imaging (MRI) results from 181 LDDD patients receiving lumbar nucleoplasty. Post-treatment pain improvements were categorized as clinically significant (defined as a ≥80% decrease in the visual analog scale) or non-significant. To develop the ML models, T2-weighted MRI images were subjected to radiomic feature extraction, which was combined with physiological clinical parameters. After data processing, we developed five ML models: support vector machine, light gradient boosting machine, extreme gradient boosting, extreme gradient boosting random forest, and improved random forest. Model performance was measured by evaluating indicators, such as the confusion matrix, accuracy, sensitivity, specificity, F1 score, and area under the receiver operating characteristic curve (AUC), which were acquired using an 8:2 allocation of training to testing sequences.

RESULTS

Among the five ML models, the improved random forest algorithm had the best performance, with an accuracy of 0.76, a sensitivity of 0.69, a specificity of 0.83, an F1 score of 0.73, and an AUC of 0.77. The most influential clinical features included in the ML models were pre-operative VAS and age. In contrast, the most influential radiomic features had the correlation coefficient and gray-scale co-occurrence matrix.

CONCLUSIONS

We developed an ML-based model for predicting pain improvement after LNP for patients with LDDD. We hope this tool will provide both doctors and patients with better information for therapeutic planning and decision-making.

Association of preoperative glucose concentration with mortality in patients undergoing craniotomy for brain tumor

OBJECTIVE

Hyperglycemia is associated with worse outcomes in ambulatory settings and specialized hospital settings, but there are sparse data on the importance of preoperative blood glucose measurement before brain tumor craniotomy. The authors sought to investigate the association between preoperative glucose level and 30-day mortality rate in patients undergoing brain tumor resection.

METHODS

This retrospective cohort study included patients undergoing craniotomy for brain tumors at West China Hospital, Sichuan University, from January 2011 to March 2021. Surgical mortality rates were evaluated in patients who had normal glycemia (< 5.6 mmol/L) as well as mild (5.6-6.9 mmol/L), moderate (7.0-11.0 mmol/L), and severe hyperglycemia (> 11.0 mmol/L).

RESULTS

The study included 12,281 patients who underwent tumor resection via craniotomy. The overall 30-day mortality rate was 2.0% (242/12,281), whereas the rates for normal glycemia and mild, moderate, and severe hyperglycemia were 1.5%, 2.5%, 3.8%, and 6.5%, respectively. Compared with normal glycemia, the odds of mortality at 30 days were higher in patients with mild hyperglycemia (adjusted odds ratio [OR] 1.44, 95% confidence interval [CI] 1.05-2.00), moderate hyperglycemia (OR 2.04, 95% CI 1.41-2.96), and severe hyperglycemia (OR 3.76, 95% CI 1.96-7.20; p < 0.001 for trend). When blood glucose was analyzed as a continuous variable, for each 1 mmol/L increase in blood glucose, the adjusted OR of 30-day mortality was 1.13 (95% CI 1.08-1.19). The addition of a preoperative glucose level significantly improved the area under the curve and categorical net reclassification index for prediction of mortality.

CONCLUSIONS

In patients undergoing craniotomy for brain tumors, even mild hyperglycemia was associated with an increased mortality rate, at a glucose level that was much lower than the commonly applied level.

Diabetic and stress-induced hyperglycemia in spontaneous intracerebral hemorrhage: A multicenter prospective cohort (CHEERY) study

INTRODUCTION

Admission hyperglycemia is a common finding after spontaneous intracerebral hemorrhage (ICH) secondary to pre-existing diabetes mellitus (DM) or stress-induced hyperglycemia (SIH). Studies of the causal relationship between SIH and ICH outcomes are rare.

AIM

We aimed to identify whether SIH or pre-existing DM was the cause of admission hyperglycemia associated with ICH outcomes.

METHODS

Admission glycosylated hemoglobin (HbA1c), glucose levels, and comorbidity data from the prospective, multicenter cohort, Chinese Cerebral Hemorrhage: Mechanisms and Intervention Study (CHEERY), were collected and analyzed. According to different admission blood glucose and HbA1c levels, patients were divided into nondiabetic normoglycemia (NDN), diabetic normoglycemia (DN), diabetic hyperglycemia (DH), and SIH groups. Modified Poisson regression models were used to analyze ICH outcomes in the different groups.

RESULTS

In total, 1372 patients were included: 388 patients with admission hyperglycemia, 239 with DH, and 149 with SIH. In patients with hyperglycemia, SIH was associated with a higher risk of pulmonary infection [risk ratios (RR): 1.477, 95% confidence interval (CI): 1.004-2.172], 30-day (RR: 1.068, 95% CI: 1.009-1.130) and 90-day mortality after ICH (RR: 1.060, 95% CI: 1.000-1.124).

CONCLUSIONS

Admission hyperglycemia is a common finding after ICH, and SIH is a sensitive predictor of the risk of pulmonary infection and all-cause death after ICH.

Pneumocephalus After Anterior Lumbar Spinal Surgery Due to Trauma: A Case Report

Pneumocephalus as a complication of anterior lumbar spinal surgery is extremely rare. A 53-year-old male patient presented with L4 fracture. Posterior fixation from L3 to L5 was conducted one day after the trauma. As the patient's neurological deficit persisted, additional anterior surgery by L4 vertebral body replacement was performed on the 19th day. Both surgeries were completed without obvious intraoperative complications. Two weeks after the anterior lumbar surgery, the patient complained of severe headaches, and computed tomography scan revealed pneumocephalus and massive fluid retention in the abdomen. The symptoms improved with conservative treatment, including bed rest, spinal drainage, intravenous drip infusion, and prophylactic administration of antibiotics. Due to the lack of tamponade effect in the soft tissues, a large amount of cerebrospinal fluid leakage may induce and cause progression of pneumocephalus in anterior dural injury.

Immune regulation in neurovascular units after traumatic brain injury

Traumatic brain injury (TBI) is a major cause of death and disability worldwide. Survivors may experience movement disorders, memory loss, and cognitive deficits. However, there is a lack of understanding of the pathophysiology of TBI-mediated neuroinflammation and neurodegeneration. The immune regulation process of TBI involves changes in the peripheral and central nervous system (CNS) immunity, and intracranial blood vessels are essential communication centers. The neurovascular unit (NVU) is responsible for coupling blood flow with brain activity, and comprises endothelial cells, pericytes, astrocyte end-feet, and vast regulatory nerve terminals. A stable NVU is the basis for normal brain function. The concept of the NVU emphasizes that cell-cell interactions between different types of cells are essential for maintaining brain homeostasis. Previous studies have explored the effects of immune system changes after TBI. The NVU can help us further understand the immune regulation process. Herein, we enumerate the paradoxes of primary immune activation and chronic immunosuppression. We describe the changes in immune cells, cytokines/chemokines, and neuroinflammation after TBI. The post-immunomodulatory changes in NVU components are discussed, and research exploring immune changes in the NVU pattern is also described. Finally, we summarize immune regulation therapies and drugs after TBI. Therapies and drugs that focus on immune regulation have shown great potential for neuroprotection. These findings will help us further understand the pathological processes after TBI.

BMP9 ameliorates amyloid pathology by promoting low-density lipoprotein receptor-related protein 1 expression in APP/PS1 transgenic mice

Alzheimer's disease (AD) is the most common cause of dementia worldwide. Our previous study revealed that bone morphogenetic protein 9 (BMP9) could ameliorate the amyloid pathology and cognitive impairments in a transgenic model of AD. However, the mechanisms underlying the protective effect of BMP9 against amyloid pathology remain unknown. Low-density lipoprotein receptor-related protein 1 (LRP1) plays an essential role in the clearance of amyloid beta. Here, we demonstrated that intranasal BMP9 significantly enhanced the expression of LRP1 in the brains of APP/PS1 mice. Importantly, silencing LRP1 significantly promoted the amyloid plaques accumulation and facilitated the neuroinflammation in the brains of BMP9-treated APP/PS1 mice. Furthermore, silencing LRP1 significantly impaired the learning and memory functions of BMP9-treated APP/PS1 mice. Our results suggest that BMP9 ameliorate the amyloid pathology and cognitive dysfunction in APP/PS1 mice by promoting the expression of LRP1.

Function of the GABAergic System in Diabetic Encephalopathy

Diabetes is a common metabolic disease characterized by loss of blood sugar control and a high rate of complications. γ-Aminobutyric acid (GABA) functions as the primary inhibitory neurotransmitter in the adult mammalian brain. The normal function of the GABAergic system is affected in diabetes. Herein, we summarize the role of the GABAergic system in diabetic cognitive dysfunction, diabetic blood sugar control disorders, diabetes-induced peripheral neuropathy, diabetic central nervous system damage, maintaining diabetic brain energy homeostasis, helping central control of blood sugar and attenuating neuronal oxidative stress damage. We show the key regulatory role of the GABAergic system in multiple comorbidities in patients with diabetes and hope that further studies elucidating the role of the GABAergic system will yield benefits for the treatment and prevention of comorbidities in patients with diabetes.

Single-cell transcriptomic atlas of Alzheimer's disease middle temporal gyrus reveals region, cell type and sex specificity of gene expression with novel genetic risk for MERTK in female

Alzheimer's disease, the most common age-related neurodegenerative disease, is closely associated with both amyloid-ß plaque and neuroinflammation. Two thirds of Alzheimer's disease patients are females and they have a higher disease risk. Moreover, women with Alzheimer's disease have more extensive brain histological changes than men along with more severe cognitive symptoms and neurodegeneration. To identify how sex difference induces structural brain changes, we performed unbiased massively parallel single nucleus RNA sequencing on Alzheimer's disease and control brains focusing on the middle temporal gyrus, a brain region strongly affected by the disease but not previously studied with these methods. We identified a subpopulation of selectively vulnerable layer 2/3 excitatory neurons that that were RORB-negative and CDH9-expressing. This vulnerability differs from that reported for other brain regions, but there was no detectable difference between male and female patterns in middle temporal gyrus samples. Disease-associated, but sex-independent, reactive astrocyte signatures were also present. In clear contrast, the microglia signatures of diseased brains differed between males and females. Combining single cell transcriptomic data with results from genome-wide association studies (GWAS), we identified MERTK genetic variation as a risk factor for Alzheimer's disease selectively in females. Taken together, our single cell dataset revealed a unique cellular-level view of sex-specific transcriptional changes in Alzheimer's disease, illuminating GWAS identification of sex-specific Alzheimer's risk genes. These data serve as a rich resource for interrogation of the molecular and cellular basis of Alzheimer's disease.

High Resolution Multiplex Confocal Imaging of the Neurovascular Unit in Health and Experimental Ischemic Stroke

The neurovascular unit (NVU) is an anatomical group of cells that establishes the blood-brain barrier (BBB) and coordinates cerebral blood flow in association with neuronal function. In cerebral gray matter, cellular constituents of the NVU include endothelial cells and associated pericytes, astrocytes, neurons, and microglia. Dysfunction of the NVU is a common feature of diseases that affect the CNS, such as ischemic stroke. High-level evaluation of these NVU changes requires the use of imaging modalities that can enable the visualization of various cell types under disease conditions. In this study, we applied our confocal microscopy strategy using commercially available labeling reagents to, for the first time, simultaneously investigate associations between endothelial cells, the vascular basal lamina, pericytes, microglia, astrocytes and/or astrocyte end-feet, and neurites in both healthy and ischemic brain tissue. This allowed us to demonstrate ischemia-induced astrocyte activation, neurite loss, and microglial migration toward blood vessels in a single confocal image. Furthermore, our labeling cocktail enabled a precise quantification of changes in neurites and astrocyte reactivity, thereby showing the relationship between different NVU cellular constituents in healthy and diseased brain tissue. The application of our imaging approach for the simultaneous visualization of multiple NVU cell types provides an enhanced understanding of NVU function and pathology, a state-of-the-art advancement that will facilitate the development of more effective treatment strategies for diseases of the CNS that exhibit neurovascular dysfunction, such as ischemic stroke.

Recent Progresses in Non-Dialysis Chronic Kidney Disease Patients with Hyperkalemia: Outcomes and Therapeutic Strategies

Chronic kidney disease (CKD) affects about 10% of the world's population. Hyperkalemia is a life-threatening complication in patients with CKD, as it is associated with adverse cardiovascular and kidney outcomes. There are still many challenges and questions to address to improve the currently available therapeutic strategies to treat hyperkalemia, such as how to approach the emergency management of hyperkalemia. In recent years, in addition to novel oral potassium binders, great progress has been made in the application of novel kidney protective strategies, such as mineralocorticoid receptor antagonists and sodium-glucose cotransporter 2 inhibitors (SGLT2i) in hyperkalemia therapy. This review will discuss the recent advances from clinical trials in the effective management of hyperkalemia in non-dialysis CKD patients, enhancing the knowledge of physicians and internists concerning these newer agents and providing a helpful reference for clinical practice.

Protecting the injured central nervous system: Do anesthesia or hypothermia ameliorate secondary injury?

Traumatic injury to the central nervous system (CNS) and stroke initiate a cascade of processes that expand the area of tissue loss. The current review considers recent studies demonstrating that the induction of an anesthetic state or cooling the affected tissue (hypothermia) soon after injury can have a therapeutic effect. We first provide an overview of the neurobiological processes that fuel tissue loss after traumatic brain injury (TBI), spinal cord injury (SCI) and stroke. We then examine the rehabilitative effectiveness of therapeutic anesthesia across a variety of drug categories through a systematic review of papers in the PubMed database. We also review the therapeutic benefits hypothermia, another treatment that quells neural activity. We conclude by considering factors related to the safety, efficacy and timing of treatment, as well as the mechanisms of action. Clinical implications are also discussed.

Imine-Linked Covalent Organic Framework Modulates Oxidative Stress in Alzheimer's Disease

Oxidative stress due to Cu²⁺-triggered aggregation of β-amyloid protein (Aβ) and reactive oxygen species (ROS) overexpression in the brain is an important hallmark of early stages of Alzheimer's disease (AD) pathogenesis. The ideal modulator for improving the oxidative stress microenvironment in AD brains should take both Cu²⁺ and ROS into consideration, which has been rarely reported. Here, a combined therapeutic strategy was achieved by co-encapsulating superoxide dismutase (SOD) and catalase (CAT) in imine-linked covalent organic frameworks (COFs), which were modified with peptide KLVFF (T5). The nanocomposite SC@COF-T5 exhibited an oxidative stress eradicating ability through ROS elimination and Cu²⁺ chelation, combined with the inhibition of Aβ42 monomer aggregation and disaggregation of Aβ42 fibrils. In vivo experiments indicated that SC@COF-T5 with a high blood-brain barrier (BBB) penetration efficiency was effective to reduce Aβ deposition, expression of pro-inflammatory cytokines, ROS levels, and neurologic damage in AD model mice, consequently rescuing memory deficits of AD mice. This work not only confirms the feasibility and merits of the therapeutic strategy regarding multiple targets for treatment of early AD pathogenesis but also opens up a novel direction for imine-linked COFs in biomedical applications.

The Role of Arginine-Vasopressin in Stroke and the Potential Use of Arginine-Vasopressin Type 1 Receptor Antagonists in Stroke Therapy: A Narrative Review

Stroke is a life-threatening condition in which accurate diagnoses and timely treatment are critical for successful neurological recovery. The current acute treatment strategies, particularly non-invasive interventions, are limited, thus urging the need for novel therapeutical targets. Arginine vasopressin (AVP) receptor antagonists are emerging as potential targets to treat edema formation and subsequent elevation in intracranial pressure, both significant causes of mortality in acute stroke. Here, we summarize the current knowledge on the mechanisms leading to AVP hyperexcretion in acute stroke and the subsequent secondary neuropathological responses. Furthermore, we discuss the work supporting the predictive value of measuring copeptin, a surrogate marker of AVP in stroke patients, followed by a review of the experimental evidence suggesting AVP receptor antagonists in stroke therapy. As we highlight throughout the narrative, critical gaps in the literature exist and indicate the need for further research to understand better AVP mechanisms in stroke. Likewise, there are advantages and limitations in using copeptin as a prognostic tool, and the translation of findings from experimental animal models to clinical settings has its challenges. Still, monitoring AVP levels and using AVP receptor antagonists as an add-on therapeutic intervention are potential promises in clinical applications to alleviate stroke neurological consequences.

Impact of glycosylated hemoglobin on early neurological deterioration in acute mild ischemic stroke patients treated with intravenous thrombolysis

Objective

In patients with acute mild ischemic stroke treated with intravenous thrombolysis, the relationship between chronic hyperglycemic status and their early neurological deterioration (END) and clinical outcomes is unclear. We attempted to analyze the relationship between glycated hemoglobin (HbA1c) levels and END and 90-day functional outcomes.

Participants and methods

The research comprised 267 patients with acute mild ischemic stroke. The incidence of END and functional outcomes at 90 days were evaluated between subgroups. END was defined in this study as a rise of at least 1 point in the National Institutes of Health Stroke Scale (NIHSS) score within 72 h of admission, with an excellent outcome of a modified Rankin Scale (mRS) score of 0-1 at 90 days following stroke beginning. The association between HbA1c and END, and clinical outcomes in patients with mild stroke, was assessed by logistic regression after adjusting for confounding factors. In addition, we used receiver operating characteristic (ROC) curves to predict the predictive value of HbA1c for the incidence of END.

Results

There were 38 patients who suffered END and 105 patients who had disabled functional outcomes at 90 days. In multivariate analysis, elevated HbA1c levels were associated with END (adjusted OR = 1.476; 95% CI: 1.129-1.928; p = 0.004). With HbA1c greater than 7.75%, the ROC curve predicted a higher risk of END. However, they were not associated with patients' functional outcomes at 90 days.

Conclusion

HbA1c levels were an independent predictor of END in patients with mild stroke, while there was no effect on functional outcomes at 90 days. The impact of HbA1c on functional prognosis may be a contributing factor rather than a direct factor.

A 6-month prognostic nomogram incorporating hemoglobin level for intracerebral hemorrhage in younger adults

OBJECTIVE

Intracerebral hemorrhage (ICH) is the second most common subtype of stroke, with high mortality and morbidity. At present, there are no effective 6-month prognostic markers, particularly for younger patients. The aim of this research was to construct a new valuable prognostic nomogram model incorporating haemoglobin levels for adult patients with ICH.

METHODS

Patients aged between 18 and 50 presenting with intracerebral haemorrhage at the Tongji Hospital, Tongji Medical College of Huazhong University of Science and Technology between January 1st 2012 and December 31st 2018 were included in this retrospective study. Independent factors of prognosis were identified by univariate and multivariate logistic regression analyses, and a new nomogram model was constructed and validated. The clinical value of the nomogram model was subsequently explored utilizing decision curve analysis and clinical impact curves.

RESULTS

In total, 565 patients were enrolled in this study, 117 (20.7%) of whom developed an unfavourable prognosis. Infratentorial lesion (adjusted odds ratio [aOR] = 3.708, 95% confidence interval [CI], 1.490-9.227; P = 0.005) was the most significant unfavourable outcome. Age ([aOR] = 1.054; 95% CI, 1.014-1.096; P = 0.008), hematoma volume (aOR = 1.014, 95% CI, 1.002-1.027; P = 0.024), haemoglobin (aOR = 0.981, 95% CI, 0.969-0.993; P = 0.002), blood glucose (aOR = 1.135, 95% CI, 1.037-1.241; P = 0.005) and NIHSS (aOR = 1.105, 95% CI, 1.069-1.141; P < 0.001) were independent risk factors. Based on these 6 factors, the nomogram can be employed to predict early functional prognosis with high accuracy (AUC 0.791). Decision curve analysis and clinical impact curves showed an increased net benefit for utilizing the nomogram.

CONCLUSION

The haemoglobin level at admission may be an easily overlooked factor in clinical work. This new nomogram model could be a promising and convenient tool to predict the early functional prognosis of adults with ICH. More prospective multicentre studies are needed to validate these findings.

The Relationship of Astrocytes and Microglia with Different Stages of Ischemic Stroke

Ischemic stroke is the predominant cause of severe morbidity and mortality worldwide. Post-stroke neuroinflammation has recently received increasing attention with the aim of providing a new effective treatment strategy for ischemic stroke. Microglia and astrocytes are major components of the innate immune system of the central nervous system. They can be involved in all phases of ischemic stroke, from the early stage, contributing to the first wave of neuronal cell death, to the late stage involving phagocytosis and repair. In the early stage of ischemic stroke, a vicious cycle exists between the activation of microglia and astrocytes (through astrocytic connexin 43 hemichannels), aggravating neuroinflammatory injury post-stroke. However, in the late stage of ischemic stroke, repeatedly activated microglia can induce the formation of glial scars by triggering reactive astrogliosis in the peri-infarct regions, which may limit the movement of activated microglia in reverse and restrict the diffusion of inflammation to healthy brain tissues, alleviating the neuroinflammatory injury poststroke. In this review, we elucidated the various roles of astrocytes and microglia and summarized their relationship with neuroinflammation. We also examined how astrocytes and microglia influence each other at different stages of ischemic stroke. Several potential therapeutic approaches targeting astrocytes and microglia in ischemic stroke have been reviewed. Understanding the details of astrocytemicroglia interaction processes will contribute to a better understanding of the mechanisms underlying ischemic stroke, contributing to the identification of new therapeutic interventions.

Direct implantation of hair-follicle-associated pluripotent (HAP) stem cells repairs intracerebral hemorrhage and reduces neuroinflammation in mouse model

Intracerebral hemorrhage (ICH) is a leading cause of mortality with ineffective treatment. Hair-follicle-associated pluripotent (HAP) stem cells can differentiate into neurons, glial cells and many other types of cells. HAP stem cells have been shown to repair peripheral-nerve and spinal-cord injury in mouse models. In the present study, HAP stem cells from C57BL/6J mice were implanted into the injured brain of C57BL/6J or nude mice with induced ICH. After allo transplantation, HAP stem cells differentiated to neurons, astrocytes, oligodendrocytes, and microglia in the ICH site of nude mice. After autologous transplantation in C57BL/6J mice, HAP stem cells suppressed astrocyte and microglia infiltration in the injured brain. The mRNA expression levels of IL-10 and TGF-β1, measured by quantitative Real-Time RT-PCR, in the brain of C57BL/6J mice with ICH was increased by HAP-stem-cell implantation compared to the non-implanted mice. Quantitative sensorimotor function analysis, with modified limb-placing test and the cylinder test, demonstrated a significant functional improvement in the HAP-stem-cell-implanted C57BL/6J mice, compared to non-implanted mice. HAP stem cells have critical advantages over induced pluripotent stem cells, embryonic stem cells as they do not develop tumors, are autologous, and do not require genetic manipulation. The present study demonstrates future clinical potential of HAP-stem-cell repair of ICH, currently a recalcitrant disease.

Toxicologic Pathology Forum Opinion: Interpretation of Gliosis in the Brain and Spinal Cord Observed During Nonclinical Safety Studies

Gliosis, defined as a nonneoplastic reaction (hypertrophy and/or proliferation) of astrocytes and/or microglial cells, is a frequent finding in the central nervous system (CNS [brain and/or spinal cord]) in nonclinical safety studies. Gliosis in rodents and nonrodents occurs at low incidence as a spontaneous finding and is induced by various test articles (e.g., biomolecules, cell and gene therapies, small molecules) delivered centrally (i.e., by injection or infusion into cerebrospinal fluid or neural tissue) or systemically. Several CNS gliosis patterns occur in nonclinical species. First, gliosis may accompany degeneration and/or necrosis of cells (mainly neurons) or neural parenchyma (neuron processes and myelin). Second, gliosis often follows inflammation (i.e., leukocyte accumulation causing parenchymal damage) or neoplasm formation. Third, gliosis may appear as variably sized, randomly scattered foci of reactive glial cells in the absence of visible parenchymal damage or inflammation. In interpreting test article-related CNS gliosis, adversity is indicated by parenchymal injury (e.g., degeneration, necrosis, or inflammation) and not the mere existence of a glial reaction. In the absence of clear structural damage to the parenchyma, gliosis as a standalone CNS finding should be interpreted as a nonadverse reaction to regional alterations in microenvironmental conditions rather than as evidence of a glial reaction associated with neurotoxicity.

Nanoparticle-based drug delivery for the treatment of traumatic brain injury

INTRODUCTION

Traumatic brain injuries (TBIs) impact the breadth of society and remain without any approved pharmacological treatments. Despite successful Phase II clinical trials, the failure of many Phase III clinical trials may be explained by insufficient drug targeting and retention, preventing the proper attainment of an observable dosage threshold. To address this challenge, nanoparticles can be functionalized to protect pharmacological payloads, improve targeted drug delivery to sites of injury, and can be combined with supportive scaffolding to improve secondary outcomes.

AREAS COVERED

This review briefly covers the pathophysiology of TBIs and their subtypes, the current pre-clinical and clinical management strategies, explores the common models of focal, diffuse, and mixed traumatic brain injury employed in experimental animals, and surveys the existing literature on nanoparticles developed to treat TBIs.

EXPERT OPINION

Nanoparticles are well suited to improve secondary outcomes as their multifunctionality and customizability enhance their potential for efficient targeted delivery, payload protection, increased brain penetration, low off-target toxicity, and biocompatibility in both acute and chronic timescales.

The efficacy and safety of asleep and awake subthalamic deep brain stimulation for Parkinson's disease patients: A 1-year follow-up

Introduction

Traditional DBS is usually conducted under local anesthesia (LA) which is intolerable to some patients, DBS under general anesthesia (GA) was opted to extended surgical indication. This study aimed to compare the efficacy and safety of bilateral subthalamic deep brain stimulation (STN-DBS) for Parkinson's disease (PD) under asleep and awake anesthesia state in 1-year postoperative follow-up.

Methods

Twenty-one PD patients were assigned to asleep group and 25 patients to awake group. Patients received bilateral STN-DBS under different anesthesia state. The PD participants were interviewed and assessed preoperatively and at 1-year postoperative follow-up.

Results

At 1-year follow-up, compared surgical coordinate in two groups, the left-side Y of asleep group showed more posterior than awake group (Y was-2.39 ± 0.23 in asleep group, -1.46 ± 0.22 in awake group, p = 0.007). Compared with preoperative OFF MED state, MDS-UPDRS III scores in OFF MED/OFF STIM state remained unchanged, while in OFF MED/ON STIM state were significantly improved in awake and asleep groups, yet without significant difference. Compared with preoperative ON MED state, MDS-UPDRS III scores in ON MED/OFF STIM, and ON MED/ON STIM state remained unchanged in both groups. In non-motor outcomes, PSQI, HAMD, and HAMA score significantly improved in asleep group compared to awake group at 1-year follow-up (PSQI, HAMD, and HAMA score in 1-year follow-up were 9.81 ± 4.43; 10.00 ± 5.80; 5.71 ± 4.75 in awake group, 6.64 ± 4.14; 5.32 ± 3.78; 3.76 ± 3.87 in asleep group, p = 0.009; 0.008; 0.015, respectively), while there was no significant difference in PDQ-39, NMSS, ESS, PDSS score, and cognitive function. Anesthesia methods was significantly associated with improvement of HAMA and HAMD score (p = 0.029; 0.002, respectively). No difference in LEDD, stimulation parameters and adverse events was observed between two groups.

Discussion

Asleep STN-DBS may be considered a good alternative method for PD patients. It is largely consistent with awake STN-DBS in motor symptoms and safety. Yet, it showed higher improvement in terms of mood and sleep compared to awake group at 1-year follow-up.

Gut microbiota, a hidden protagonist of traditional Chinese medicine for acute ischemic stroke

Acute ischemic stroke (AIS) is one of the leading diseases causing death and disability worldwide, and treatment options remain very limited. Traditional Chinese Medicine (TCM) has been used for thousands of years to treat ischemic stroke and has been proven to have significant efficacy, but its mechanism of action is still unclear. As research related to the brain-gut-microbe axis progresses, there is increasing evidence that the gut microbiota plays an important role during AIS. The interaction between TCM and the gut microbiota has been suggested as a possible key link to the therapeutic effects of TCM. We have compiled and reviewed recent studies on the relationship between AIS, TCM, and gut microbiota, with the expectation of providing more ideas to elucidate the mechanism of action of TCM in the treatment of AIS.

Comparison of Quality of Life Between Breast Cancer Patients Treated With and Without Adjunctive Traditional Chinese Medicine in Taiwan

In Taiwan, breast cancer has the highest incidence among all cancers. Although adjunctive traditional Chinese medicine treatment (TCM) have been used to ameliorate the side effects or discomfort caused by cancer treatments, no study has focused on the assessment of the quality of life of patients undergoing adjunctive TCM treatments. This study compared the quality of life between breast cancer patients treated with and without adjunctive TCM. Questionnaires were collected from 7 hospitals with a Chinese medicine clinic in 2018 to 2019. Breast cancer patients who had cancer stages I, II, or III and also underwent resection surgery were included in the study. They were divided into 2 groups: patients receiving cancer treatments with adjunctive traditional Chinese medicine (TCM group) and those receiving cancer treatments without adjunctive traditional Chinese medicine (non-TCM group). A 1:1 matching was used to obtain the study participants. The EQ-5D questionnaire was used to assess the quality of life. Statistical analysis was performed using the t-test and ANOVA to compare the differences between variables. The conditional multiple regression model was applied to explore the factors associated with quality of life in breast cancer patients. A total of 543 participants were surveyed, and 450 participants were included in the study. The EQ-5D score of the TCM group (81.60 ± 11.67) was significantly higher than that of the non-TCM group (78.80 ± 13.10; P < .05). The results of a conditional multiple regression model showed that the TCM group had a higher (3.45 points) quality of life than non-TCM group (P = .002) after adjusting for other related factors. After stratifying by cancer stage, patients with cancer stages II and III scored 5.58 and 4.35 points higher in the TCM group than did those in the non-TCM group (P < .05). Breast cancer patients undergoing cancer treatment with adjunctive traditional Chinese medicine have a higher quality of life than those treated without adjunctive traditional Chinese medicine.

Secondary White Matter Injury Mediated by Neuroinflammation after Intracerebral Hemorrhage and Promising Therapeutic Strategies of Targeting the NLRP3 Inflammasome

Intracerebral hemorrhage (ICH) is a neurological disease with high mortality and disability. Recent studies showed that white matter injury (WMI) plays an important role in motor dysfunction after ICH. WMI includes WMI proximal to the lesion and WMI distal to the lesion, such as corticospinal tract injury located at the cervical enlargement of the spinal cord after ICH. Previous studies have tended to focus only on gray matter (GM) injury after ICH, and fewer studies have paid attention to WMI, which may be one of the reasons for the poor outcome of previous drug treatments. Microglia and astrocyte-mediated neuroinflammation are significant mechanisms responsible for secondary WMI following ICH. The NOD-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome activation, has been shown to exacerbate neuroinflammation and brain injury after ICH. Moreover, NLRP3 inflammasome is activated in microglia and astrocytes and exerts a vital role in microglia and astrocytes-mediated neuroinflammation. We speculate that NLRP3 inflammasome activation is closely related to the polarization of microglia and astrocytes and that NLRP3 inflammasome activation may exacerbate WMI by polarizing microglia and astrocytes to the pro-inflammatory phenotype after ICH, while NLRP3 inflammasome inhibition may attenuate WMI by polarizing microglia and astrocytes to the anti-inflammatory phenotype following ICH. Therefore, NLRP3 inflammasome may act as leveraged regulatory fulcrums for microglia and astrocytes polarization to modulate WMI and WM repair after ICH. This review summarized the possible mechanisms by which neuroinflammation mediated by NLRP3 inflammasome exacerbates secondary WMI after ICH and discussed the potential therapeutic targets.

Epilepsy in Cerebrovascular Diseases: A Narrative Review

BACKGROUND

Epilepsy is a common comorbidity of cerebrovascular disease and an increasing socioeconomic burden.

OBJECTIVE

We aimed to provide an updated comprehensive review on the state of the art about seizures and epilepsy in stroke, cerebral haemorrhage, and leukoaraiosis.

METHODS

We selected English-written articles on epilepsy, stroke, and small vessel disease up until December 2021. We reported the most recent data about epidemiology, pathophysiology, prognosis, and management for each disease.

RESULTS

The main predictors for both ES and PSE are the severity and extent of stroke, the presence of cortical involvement and hemorrhagic transformation, while PSE is also predicted by younger age at stroke onset. Few data exist on physiopathology and seizure semiology, and no randomized controlled trial has been performed to standardize the therapeutic approach to post-stroke epilepsy.

CONCLUSION

Some aspects of ES and PSE have been well explored, particularly epidemiology and risk factors. On the contrary, few data exist on physiopathology, and existing evidence is mainly based on studies on animal models. Little is also known about seizure semiology, which may also be difficult to interpret by non-epileptologists. Moreover, the therapeutic approach needs standardization as regards indications and the choice of specific ASMs. Future research may help to better elucidate these aspects.

The effects of microglia-associated neuroinflammation on Alzheimer's disease

Alzheimer's disease (AD) is defined as a severe chronic degenerative neurological disease in human. The pathogenic mechanism of AD has been convincingly elucidated by the "amyloid cascade hypothesis" with the main focus of the pathological accretion of β-amyloid (Aβ) peptides outside the cell. However, increasing evidence suggests that this hypothesis is weak in explaining the pathogenesis of AD. Neuroinflammation is crucial in the development of AD, which is proven by the elevated levels of inflammatory markers and the identification of AD risk genes relevant to the innate immune function. Here, we summarize the effects of microglia-mediated neuroinflammation on AD, focusing on the temporal and spatial changes in microglial phenotype, the interactions among microglia, Aβ, tau, and neurons, and the prospects and recent advances in neuroinflammation as a diagnostic and therapeutic target of AD.

BYHW Decoction Improves Cognitive Impairments in Rats with Cerebral Microinfarcts via Activation of the PKA/CREB Pathway

Cerebral microinfarcts (CMIs) are characterized by sporadic obstruction of small vessels leading to neurons death. They are associated with increased risk of cognitive impairments and may have different risk factors compared with macroinfarcts. CMIs have a high incidence and result in heavy social burden; thus, it is essential to provide reasonable treatment in clinical practice. However, there are relatively few researches on the mechanism and treatment of CMIs, and the literature is composed almost exclusively of community-or hospital based on autopsy or imageological studies focusing on elderly patients. The Bu Yang Huan Wu (BYHW) decoction, a traditional Chinese herbal formula, has long been used to treat stroke and stroke-related diseases, including cognitive impairments. We applied microsphere-induced CMI model in rats to investigate the behavioral and molecular consequences of CMIs and to determine how they were ameliorated by BYHW decoction treatment. We then used the Morris water maze, quantitative proteomics, immunohistochemistry, and other molecular assays and found that activation of the PKA/CREB pathway by BYHW decoction treatment may reverse mitochondrial dysfunction, inhibit apoptosis of hippocampal neurons, and ameliorate CMI-induced cognitive impairments in rats. Collectively, these findings confirmed the therapeutic potential of the BYHW decoction in treating cognitive impairments induced by CMIs and demonstrated a viable mechanism for its action.

Tension Pneumocephalus Caused by Ethmoidal Roof Fracture: Emergent Surgical Decompression

Tension pneumocephalus is a neurosurgical emergency that occurs when air is trapped in the intracranial cavity, leading to brain compression and causing severe neurological symptoms such as decreases in motor function, sensory function, and consciousness. Most cases of pneumocephalus require conservative treatment; however, because of the possible fatal complications, rapid diagnosis and appropriate treatment are important. Here, we present the case of an 81-year-old male patient who had undergone head trauma three hours prior to being admitted to our emergency room (ER) because of mental cloudiness. The radiologic findings showed tension pneumocephalus caused by an ethmoidal roof fracture. Emergency reconstruction of the ethmoidal roof with craniotomy was performed to remove the intracranial air using normal saline irrigation. By sharing our experience with this case, we hope to provide an option for the treatment of such cases.

The role of circadian clock in astrocytes: From cellular functions to ischemic stroke therapeutic targets

Accumulating evidence suggests that astrocytes, the abundant cell type in the central nervous system (CNS), play a critical role in maintaining the immune response after cerebral infarction, regulating the blood-brain barrier (BBB), providing nutrients to the neurons, and reuptake of glutamate. The circadian clock is an endogenous timing system that controls and optimizes biological processes. The central circadian clock and the peripheral clock are consistent, controlled by various circadian components, and participate in the pathophysiological process of astrocytes. Existing evidence shows that circadian rhythm controls the regulation of inflammatory responses by astrocytes in ischemic stroke (IS), regulates the repair of the BBB, and plays an essential role in a series of pathological processes such as neurotoxicity and neuroprotection. In this review, we highlight the importance of astrocytes in IS and discuss the potential role of the circadian clock in influencing astrocyte pathophysiology. A comprehensive understanding of the ability of the circadian clock to regulate astrocytes after stroke will improve our ability to predict the targets and biological functions of the circadian clock and gain insight into the basis of its intervention mechanism.

A Nomogram Based on CT Radiomics and Clinical Risk Factors for Prediction of Prognosis of Hypertensive Intracerebral Hemorrhage

PURPOSE

To develop and validate a clinical-radiomics nomogram based on clinical risk factors and CT radiomics feature to predict hypertensive intracerebral hemorrhage (HICH) prognosis.

METHODS

A total of 195 patients with HICH treated in our hospital from January 2018 to January 2022 were retrospectively enrolled and randomly divided into two cohorts for training (n = 138) and validation (n = 57) according to the ratio of 7 : 3. All CT radiomics features were extracted from intrahematomal, perihematomal, and combined intra- and perihematomal regions by using free open-source software called 3D slicer. The least absolute shrinkage and selection operator method was used to select the optimal radiomics features, and the radiomics score (Rad-score) was calculated. The relationship between Rad-score, clinical risk factors, and the HICH prognosis was analyzed by univariate and multivariate logistic regression analyses, and the clinical-radiomics nomogram was built. The area under the receiver operating characteristic curve (AUC) and decision curve analysis (DCA) were used to evaluate the performance of the clinical-radiomics nomogram in predicting the prognosis of HICH.

RESULTS

A total of 1702 radiomics features were extracted from the CT images of each patient for analysis. By univariate and stepwise multivariate logistic regression analyses, age, sex, RBC, serum glucose, D-dimer level, hematoma volume, and midline shift were clinical risk factors for the prognosis of HICH. Rad-score and clinical risk factors developed the clinical-radiomics nomogram. The nomogram showed the highest predictive efficiency in the training cohort (AUC = 0.95, 95% confidence interval (CI), 0.92 to 0.98) and the validation cohort (AUC = 0.90, 95% CI, 0.82 to 0.98). The calibration curve indicated that the clinical-radiomics nomogram had good calibration. DCA showed that the nomogram had high applicability in clinical practice.

CONCLUSIONS

The clinical-radiomics nomogram incorporated with the radiomics features and clinical risk factors has good potential in predicting the prognosis of HICH.

Cattle Encephalon Glycoside and Ignotin Attenuates Aβ1-42-Mediated Neurotoxicity by Preventing NLRP3 Inflammasome Activation and Modulating Microglial Polarization via TLR4/NF-κB Signaling Pathway

The NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome activation-mediated microglial polarization and chronic neuroinflammation play a crucial role in the process of Alzheimer's disease (AD). The previous study has shown that cattle encephalon glycoside and ignotin (CEGI) exerted an anti-inflammatory effect and inhibited inflammatory cytokines release by downregulating the Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) pathway in AD models. However, it is not clear whether CEGI can inhibit NLRP3 inflammasome activation and regulate the polarization of microglia in AD and whether its effects rely on TLR4/NF-κB signaling pathway. In the present study, we found that CEGI attenuated amyloid-β (Aβ)1-42-induced apoptosis, increased Aβ degrading enzymes (insulin-degrading enzyme and neprilysin), and promoted the clearance of Aβ1-42 in BV2 cells. CEGI also restrained the expression of NLRP3 and M1 microglial marker (inducible nitric oxide synthase) and elevated the expression of M2 microglial markers (arginase-1 and CD206). Meanwhile, knockdown of TLR4 with small interfering RNA proved that TLR4/NF-κB signaling was involved in the effects of CEGI. Furthermore, the roles of CEGI in inhibiting NLRP3 inflammasome activation, modulating microglia M1/M2 polarization, and increasing Aβ degrading enzyme expression were further validated in vivo using APP/PS1 mice. In conclusion, CEGI promotes Aβ degradation and protects microglia against Aβ1-42-induced neurotoxicity by preventing NLRP3 inflammasome activation and regulating M1/M2 polarization via TLR4/NF-κB pathways.

Disynaptic effect of hilar cells on pattern separation in a spiking neural network of hippocampal dentate gyrus

We study the disynaptic effect of the hilar cells on pattern separation in a spiking neural network of the hippocampal dentate gyrus (DG). The principal granule cells (GCs) in the DG perform pattern separation, transforming similar input patterns into less-similar output patterns. In our DG network, the hilus consists of excitatory mossy cells (MCs) and inhibitory HIPP (hilar perforant path-associated) cells. Here, we consider the disynaptic effects of the MCs and the HIPP cells on the GCs, mediated by the inhibitory basket cells (BCs) in the granular layer; MC → BC → GC and HIPP → BC → GC. The MCs provide disynaptic inhibitory input (mediated by the intermediate BCs) to the GCs, which decreases the firing activity of the GCs. On the other hand, the HIPP cells disinhibit the intermediate BCs, which leads to increasing the firing activity of the GCs. In this way, the disynaptic effects of the MCs and the HIPP cells are opposite. We investigate change in the pattern separation efficacy by varying the synaptic strength K ( BC , X ) [from the pre-synaptic X (= MC or HIPP) to the post-synaptic BC]. Thus, sparsity for the firing activity of the GCs is found to improve the efficacy of pattern separation, and hence the disynaptic effects of the MCs and the HIPP cells on the pattern separation become opposite ones. In the combined case when simultaneously changing both K ( BC , MC ) and K ( BC , HIPP ) , as a result of balance between the two competing disynaptic effects of the MCs and the HIPP cells, the efficacy of pattern separation is found to become the highest at their original default values where the activation degree of the GCs is the lowest. We also note that, while the GCs perform pattern separation, sparsely synchronized rhythm is found to appear in the population of the GCs. Hence, we examine quantitative association between population and individual firing behaviors in the sparsely synchronized rhythm and pattern separation. They are found to be strongly correlated. Consequently, the better the population and individual firing behaviors in the sparsely synchronized rhythm are, the more pattern separation efficacy becomes enhanced.

Stroke-associated infection in patients with co-morbid diabetes mellitus is associated with in-hospital mortality

BACKGROUND AND OBJECTIVE

The association between infection and acute ischemic stroke (AIS) with diabetes mellitus (DM) remains unknown. Therefore, this study aimed to explore the effect of infection on AIS with DM.

MATERIALS AND METHODS

The data of patients with AIS and DM were extracted from the Chinese Stroke Center Alliance (CSCA) database from August 2015 to July 2019. The association between infections [pneumonia or urinary tract infection (UTI)] and in-hospital mortality was analyzed. Logistic regression models were used to identify the risk factors for in-hospital mortality of patients with infection.

RESULTS

In total, 1,77,923 AIS patients with DM were included in the study. The infection rate during hospitalization was 10.5%, and the mortality rate of infected patients was 3.4%. Stroke-associated infection was an independent risk factor for an early poor functional outcome [odds ratio (OR) = 2.26, 95% confidence interval (CI): 1.97-2.34, P < 0.0001] and in-hospital mortality in AIS patients with DM. The in-hospital mortality after infection was associated with age (OR = 1.02, 95% CI: 1.01-1.03, P < 0.0001), male (OR = 1.39, 95% CI: 1.13-1.71, P = 0.0018), reperfusion therapy (OR = 2.00, 95% CI: 1.56-2.56, P < 0.0001), and fasting plasma glucose at admission (OR = 1.05, 95% CI: 1.03-1.08, P < 0.0001). In contrast, antiplatelet drug therapy (OR = 0.63, 95% CI: 0.50-0.78, P < 0.0001) and hospital stay (OR = 0.96, 95% CI: 0.94-0.97, P < 0.0001) were independent protecting factors against in-hospital mortality of patients with infection.

CONCLUSION

Infection is an independent risk factor of in-hospital mortality for patients with AIS and DM, and those patients require strengthening nursing management to prevent infection.

Analysis of medical service utilization for post-stroke sequelae in Korea between 2016 and 2018: a cross-sectional study

In this retrospective cross-sectional observational study, the medical service utilization of post-stroke sequelae patients was examined using a national patient sample. The Korean Health Insurance Review and Assessment Service-National Patients Sample database was used to investigate the medical service utilization of 19,562 patients, diagnosed with post-stroke sequelae of cerebrovascular disease (I69) in Korea between January 2016 and December 2018. We compared the demographic characteristics, diagnosis code subtypes, frequency of healthcare utilization, medical costs, and comorbidities of standard care (SC) and Korean medicine (KM) users. Overall, patients aged ≥ 65 years accounted for the highest percentage, and utilization of medical services increased among patients aged ≥ 45 years. Outpatient care was higher among SC (79.23%) and KM (99.38%) users. Sequelae of cerebral infarction accounted for the highest percentage of diagnosis subtypes. Physical therapy and rehabilitation therapy were most frequent in SC, whereas injection/procedure and acupuncture were most frequent in KM. Cerebrovascular circulation/dementia drugs were prescribed most frequently in SC. Circulatory, digestive, endocrine, and metabolic disorders were the most common comorbidities in SC, whereas musculoskeletal and connective tissue disorders were most common in KM. Overall, SC and KM users showed differences in the number of medical service claims, cost of care, and comorbidities. Our findings provide basic research data for clinicians, researchers, and policy makers.

Arbuscular mycorrhiza alters the nutritional requirements in Salvia miltiorrhiza and low nitrogen enhances the mycorrhizal efficiency

Salvia miltiorrhiza Bunge (danshen in Chinese) is one of the most important medicinal cash crops in China. Previously, we showed that arbuscular mycorrhizal fungi (AMF) can promote S. miltiorrhiza growth and the accumulation of bioactive compounds. Fertilization may affect mycorrhizal efficiency, and appropriate doses of phosphate (P) and nitrogen (N) fertilizers are key factors for obtaining mycorrhizal benefits. However, the optimal fertilization amount for mycorrhizal S. miltiorrhiza remains unclear. In this study, we studied the effects of AMF on the growth and bioactive compounds of S. miltiorrhiza under different doses (low, medium, and high) of P and N fertilizer. The results showed that the mycorrhizal growth response (MGR) and mycorrhizal response of bioactive compounds (MBC) decreased gradually with increasing P addition. Application of a low (N25) dose of N fertilizer significantly increased the MGR of mycorrhizal S. miltiorrhiza, and a medium (N50) dose of N fertilizer significantly increased the MBC of phenolic acids, but decreased the MBC of tanshinones. Our results also showed that the existence of arbuscular mycorrhiza changes nutrient requirement pattern of S. miltiorrhiza. P is the limiting nutrient of non-mycorrhizal plants whereas N is the limiting nutrient of mycorrhizal plants.

Bridging the gap of axonal regeneration in the central nervous system: A state of the art review on central axonal regeneration

Neuronal regeneration in the central nervous system (CNS) is an important field of research with relevance to all types of neuronal injuries, including neurodegenerative diseases. The glial scar is a result of the astrocyte response to CNS injury. It is made up of many components creating a complex environment in which astrocytes play various key roles. The glial scar is heterogeneous, diverse and its composition depends upon the injury type and location. The heterogeneity of the glial scar observed in different situations of CNS damage and the consequent implications for axon regeneration have not been reviewed in depth. The gap in this knowledge will be addressed in this review which will also focus on our current understanding of central axonal regeneration and the molecular mechanisms involved. The multifactorial context of CNS regeneration is discussed, and we review newly identified roles for components previously thought to solely play an inhibitory role in central regeneration: astrocytes and p75NTR and discuss their potential and relevance for deciding therapeutic interventions. The article ends with a comprehensive review of promising new therapeutic targets identified for axonal regeneration in CNS and a discussion of novel ways of looking at therapeutic interventions for several brain diseases and injuries.

Review of Research on Road Traffic Operation Risk Prevention and Control

Road traffic safety can be ensured by preventing and controlling the potential risks in road traffic operations. The relevant literature was systematically reviewed to identify the research context and status quo in the road traffic operation risk prevention and control field and identify the key study contents needing further research. As research material, the related English and Chinese literature published between 1996 and 2021 (as of 31st December 2021) was obtained through the Web of Science Core Collection and Chinese Science Citation Database. These research materials include 22,403 English and 7876 Chinese papers. Based on the bibliometrics, this study used CiteSpace software to conduct keyword co-occurrence analysis in the field. The results show that the relevant research topics mainly covered the risks of drivers, vehicles, roads, and the traffic environment. In the aspect of driver risks, the studies focused on driving behavior characteristics. In terms of vehicle risks, the related studies were mainly about the vehicle control system, driving assistance system, hazardous material transportation, automated driving technology, safe driving speed, and vehicle collision prediction. For the road risks, the safe driving guarantee of high-risk road sections, driving risks at intersections, and safe road alignment design were the three study hotspots. In terms of traffic environment risks, identifying traffic risk locations and driving safety guarantees under adverse weather conditions were the two main research highlights. Moreover, mathematical modeling was the main method for studying road traffic operation risk. Furthermore, the impact of environmental factors on drivers, the emergency rescue system for road traffic accidents, the connection between automated driving technology and safe driving theory, and the man-machine hybrid traffic flow characteristics are the subjects needing further research.