Cortical hemorrhage-associated neurological deficits and tissue damage in mice are ameliorated by therapeutic treatment with nicotine

Spontaneous Cortical Intracerebral Hemorrhage Causing Ipsilateral Hand and Oral Sensory Change Without Motor Deficit: A Case Report

Intracerebral hemorrhage (ICH) is the second most common stroke subtype associated with high morbidity and mortality rates. Although various brain regions are susceptible to ICH, putaminal hemorrhage is the most common, whereas cortical ICH is less common. Here, we report the case of a 69-year-old man who developed a parietal cortical ICH. The patient developed hypoesthesia and paresthesia in the right upper lip and hand; however, the weakness was not severe. Twenty-five days after the ICH onset, the manual muscle test results were normal, but he had difficulty eating and shaving because of decreased hand dexterity. The rehabilitation focused on improving fine hand motor function and endurance. On the 94th day after ICH onset, paresthesia remained only in the fingertips, and the upper lip sensory change disappeared. Patients with sensory symptoms in the perioral area, hands, and brain lesions were previously referred to as having cheiro-oral syndrome (COS). With the advancement of neuroimaging, the use of this term has decreased, as cerebrovascular events can explain patient symptoms in correlation with neuroanatomy, etiology, and pathogenesis. We report a patient with cortical ICH, also known as COS, which is a stroke syndrome with a good prognosis.

A Review on Natural Antioxidants for Their Role in the Treatment of Parkinson's Disease

The neurodegenerative condition known as Parkinson's disease (PD) is brought on by the depletion of dopaminergic neurons in the basal ganglia, which is the brain region that controls body movement. PD occurs due to many factors, from which one of the acknowledged effects of oxidative stress is pathogenic pathways that play a role in the development of Parkinson's disease. Antioxidants, including flavonoids, vitamins E and C, and polyphenolic substances, help to reduce the oxidative stress brought on by free radicals. Consequently, this lowers the risk of neurodegenerative disorders in the long term. Although there is currently no cure for neurodegenerative illnesses, these conditions can be controlled. The treatment of this disease lessens its symptoms, which helps to preserve the patient's quality of life. Therefore, the use of naturally occurring antioxidants, such as polyphenols, which may be obtained through food or nutritional supplements and have a variety of positive effects, has emerged as an appealing alternative management strategy. This article will examine the extent of knowledge about antioxidants in the treatment of neurodegenerative illnesses, as well as future directions for research. Additionally, an evaluation of the value of antioxidants as neuroprotective agents will be provided.

A Nurr1 ligand C-DIM12 attenuates brain inflammation and improves functional recovery after intracerebral hemorrhage in mice

We have previously reported that amodiaquine, a compound that binds to the ligand-binding domain of a nuclear receptor Nurr1, attenuates inflammatory responses and neurological deficits after intracerebral hemorrhage (ICH) in mice. 1,1-Bis(3'-indolyl)-1-(p-chlorophenyl)methane (C-DIM12) is another Nurr1 ligand that recognizes a domain of Nurr1 different from the ligand-binding domain. In the present study, mice were treated daily with C-DIM12 (50 or 100 mg/kg, p.o.) or amodiaquine (40 mg/kg, i.p.), or twice daily with 1400 W (20 mg/kg, i.p.), an inducible nitric oxide synthase (iNOS) inhibitor, from 3 h after ICH induction by microinjection of collagenase into the striatum. C-DIM12 improved the recovery of neurological function and prevented neuron loss in the hematoma, while suppressed activation of microglia/macrophages and expression of inflammatory mediators interleukin-6 and CC chemokine ligand 2. In addition, C-DIM12 as well as amodiaquine preserved axonal structures in the internal capsule and axonal transport function. We also found that C-DIM12 and amodiaquine suppressed the increases of iNOS mRNA expression after ICH. Moreover, 1400 W improved neurological function and prevented neuron loss, activation of microglia/macrophages and axonal transport dysfunction. These results suggest that suppression of iNOS induction contributes to several features of the therapeutic effects of Nurr1 ligands.

Potential application of intranasal insulin delivery for treatment of intracerebral hemorrhage: A review of the literature

Intracerebral hemorrhage (ICH) is a devastating subtype of stroke associated with high morbidity and mortality that is considered a medical emergency, mainly managed with adequate blood pressure control and creating a favorable hemostatic condition. However, to date, none of the randomized clinical trials have led to an effective treatment for ICH. It is vital to better understand the mechanisms underlying brain injury to effectively decrease ICH-associated morbidity and mortality. It is well known that initial hematoma formation and its expansion have detrimental consequences. The literature has recently focused on other pathological processes, including oxidative stress, neuroinflammation, blood-brain barrier disruption, edema formation, and neurotoxicity, that constitute secondary brain injury. Since conventional management has failed to improve clinical outcomes significantly, various neuroprotective therapies are tested in preclinical and clinical settings. Unlike intravenous administration, intranasal insulin can reach a higher concentration in the cerebrospinal fluid without causing systemic side effects. Intranasal insulin delivery has been introduced as a novel neuroprotective agent for certain neurological diseases, including ischemic stroke, subarachnoid hemorrhage, and traumatic brain injury. Since there is an overlap of mechanisms causing neuroinflammation in these neurological diseases and ICH, we believe that preclinical studies testing the role of intranasal insulin therapy in ICH are warranted.

Chronic Nicotine Exposure Increases Hematoma Expansion Following Collagenase-Induced Intracerebral Hemorrhage in Rats

Spontaneous intracerebral hemorrhage (sICH) is a deadly stroke subtype, and tobacco use increases sICH risk. However epidemiological studies show that, there are no confirmatory studies showing the effect of tobacco use on sICH outcome. Therefore, we evaluated the effect of chronic nicotine exposure (as a surrogate for tobacco use) on outcomes following sICH. Young male and female rats were randomly assigned to either nicotine (4.5 mg/kg b.w. per day) or vehicle (saline) treatment (2–3 weeks) groups. sICH was induced by injecting collagenase into the right striatum. Neurological score and hematoma volume were determined 24 h post-sICH. The hematoma volumes in nicotine-treated male and female rats were significantly higher by 42% and 48% when compared to vehicle-treated male and female rats, respectively. Neurological deficits measured in terms of neurological score for the nicotine-treated male and female groups were significantly higher when compared to the respective vehicle-treated male and female groups. Our results show that chronic nicotine exposure increases hematoma volume post-sICH in rats of both sexes. Identifying the mechanism of nicotine-dependent increase in hematoma growth post-sICH will be crucial to understanding the detrimental effect of tobacco use on the severity of bleeding following intracerebral hemorrhage.

Microglia Phenotype and Intracerebral Hemorrhage: A Balance of Yin and Yang

Intracerebral hemorrhage (ICH) features extremely high rates of morbidity and mortality, with no specific and effective therapy. And local inflammation caused by the over-activated immune cells seriously damages the recovery of neurological function after ICH. Fortunately, immune intervention to microglia has provided new methods and ideas for ICH treatment. Microglia, as the resident immune cells in the brain, play vital roles in both tissue damage and repair processes after ICH. The perihematomal activated microglia not only arouse acute inflammatory responses, oxidative stress, excitotoxicity, and cytotoxicity to cause neuron death, but also show another phenotype that inhibit inflammation, clear hematoma and promote tissue regeneration. The proportion of microglia phenotypes determines the progression of brain tissue damage or repair after ICH. Therefore, microglia may be a promising and imperative therapeutic target for ICH. In this review, we discuss the dual functions of microglia in the brain after an ICH from immunological perspective, elaborate on the activation mechanism of perihematomal microglia, and summarize related therapeutic drugs researches.

Effects of Smoking on Short-Term and Long-Term Mortality after Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE

The relationship between smoking and clinical outcomes after aneurysmal subarachnoid hemorrhage (aSAH) is poorly clarified, and current pieces of evidence are inconsistent. The purpose of this multicenter cohort study is therefore to explore the relationship between smoking and mortality as well as several complications after aSAH.

METHODS

Databases of patient records were from 4 tertiary hospitals. We assessed the impact of tobacco use and tobacco dose (categorized based on smoking index [SI]) on several complication and overall outcome variables. The primary outcome was mortality within the longest follow-up. Logistic models were used to investigate univariate and multivariate relationships between predictors and outcomes. We also developed a propensity score matching for smoking status by using all known confounders.

RESULTS

A total of 6,578 patients with aSAH were analyzed. Current smoking and former smoking did not show association with mortality within the longest follow-up (odds ratio [OR], 0.95, 95% confidence interval [CI]: 0.69-1.30, p = 0.726; OR, 0.66, 95% CI: 0.38-1.15, p = 0.139, respectively). In addition, patients who were current smokers showed an independent association with the decreased occurrence of hydrocephalus (OR, 0.60; 95% CI: 0.41-0.88; p = 0.009) after matching all known confounders. We also found moderate smoking (SI between 384 and 625) was associated with reduced mortality in hospital.

CONCLUSIONS

Our results indicated that in patients with aSAH, current smoking or former smoking was not associated with all-cause mortality up to 7-year follow-up.

Neuroprotective Therapies for Spontaneous Intracerebral Hemorrhage

Patients who survive the initial ictus of spontaneous intracerebral hemorrhage (ICH) remain vulnerable to subsequent injury of the perilesional parenchyma by molecular and cellular responses to the hematoma. Secondary brain injury after ICH, which contributes to long-term functional impairment and mortality, has emerged as an attractive therapeutic target. This review summarizes preclinical and clinical evidence for neuroprotective therapies targeting secondary injury pathways following ICH. A focus on therapies with pleiotropic antiinflammatory effects that target thrombin-mediated chemotaxis and inflammatory cell migration has led to studies investigating statins, anticholinergics, sphingosine-1-phosphate receptor modulators, peroxisome proliferator activated receptor gamma agonists, and magnesium. Attempts to modulate ICH-induced blood-brain barrier breakdown and perihematomal edema formation has prompted studies of nonsteroidal antiinflammatory agents, matrix metalloproteinase inhibitors, and complement inhibitors. Iron chelators, such as deferoxamine and albumin, have been used to reduce the free radical injury that ensues from erythrocyte lysis. Stem cell transplantation has been assessed for its potential to enhance subacute neurogenesis and functional recovery. Despite promising preclinical results of numerous agents, their outcomes have not yet translated into positive clinical trials in patients with ICH. Further studies are necessary to improve our understanding of the molecular events that promote damage and inflammation of the perihematomal parenchyma after ICH. Elucidating the temporal and pathophysiologic features of this secondary brain injury could enhance the clinical efficacy of neuroprotective therapies for ICH.

Interactions between reproductive transitions during aging and addiction: promoting translational crosstalk between different fields of research

Discovery of neural mechanisms underlying neuropsychiatric disorders within the aging and addiction fields has been a main focus of the National Institutes of Health. However, there is a dearth of knowledge regarding the biological interactions of aging and addiction, which may have important influences on progression of disease and treatment outcomes in aging individuals with a history of chronic drug use. Thus, there is a large gap in these fields of research, which has slowed progress in understanding and treating substance use disorders (SUDs) as well as age-related diseases, specifically in women who experience precipitous reproductive cycle transitions during aging. The goal of this review is to highlight overlap of SUDs and age-related processes with a specific focus on menopause and smoking, and identify critical gaps. We have narrowed the focus of the review to smoking, as the majority of findings on hormonal and aging influences on drug use have come from this area of research. Further, we highlight female-specific issues such as transitional menopause and exogenous estrogen use. These issues may impact drug use cessation as well as outcomes with aging and age-related neurodegenerative diseases in women. We first review clinical studies for smoking, normal aging, and pathological aging, and discuss the few aging-related studies taking smoking history into account. Conversely, we highlight the dearth of clinical smoking studies taking age as a biological variable into account. Preclinical and clinical literature show that aging, age-related pathological brain disease, and addiction engage overlapping neural mechanisms. We hypothesize that these putative drivers interact in meaningful ways that may exacerbate disease and hinder successful treatment outcomes in such comorbid populations. We highlight areas where preclinical studies are needed to uncover neural mechanisms in aging and addiction processes. Collectively, this review highlights the need for crosstalk between different fields of research to address medical complexities of older adults, and specifically women, who smoke.

Tobacco Use: A Major Risk Factor of Intracerebral Hemorrhage

Spontaneous intracerebral hemorrhage (sICH) is one of the deadliest subtypes of stroke, and no treatment is currently available. One of the major risk factors is tobacco use. In this article, we review literature on how tobacco use affects the risk of sICH and also summarize the known effects of tobacco use on outcomes following sICH. Several studies demonstrate that the risk of sICH is higher in current cigarette smokers compared to non-smokers. The literature also establishes that cigarette smoking not only increases the risk of sICH but also increases hematoma growth, results in worse outcomes, and increases the risk of death from sICH. This review also discusses potential mechanisms activated by tobacco use which result in an increase in risk and severity of sICH. Exploring the underlying mechanisms may help alleviate the risk of sICH in tobacco users as well as may help better manage tobacco user sICH patients.

Microglia-released leukotriene B4 promotes neutrophil infiltration and microglial activation following intracerebral hemorrhage

Intracerebral hemorrhage (ICH) from blood vessel rupture results in parenchymal hematoma formation and neuroinflammation, ultimately leading to neurodegeneration. Several lines of evidence suggest that the severity of ICH-induced neural damage is exacerbated by infiltration of T-cells, monocytes, and especially neutrophils into the hematoma. Neutrophil migration is regulated by chemokines, formyl peptides, and leukotriene B₄ (LTB₄), a metabolite of arachidonic acid. In this study, we demonstrate that LTB₄ is a key signaling factor promoting microglial activity and leukocyte infiltration into hematoma and thus a potentially critical determinant of ICH pathogenesis and clinical outcome. Lipidomic analysis revealed markedly increased LTB₄ concentration in the hematoma-containing brain tissues 6-24 h after experimental ICH in mice. Expression of 5-lipoxygenase, a rate-limiting enzyme for LTB₄ production, was upregulated in activated microglia and neutrophils within the hematoma following ICH. Treatment of cultured BV-2 microglia with thrombin, which is abundant in hematoma, promoted activation, proinflammatory cytokine expression, and LTB₄ secretion. Further, conditioned medium from thrombin-stimulated BV-2 cells potentiated the transwell migration of neutrophil-like cells, a response blocked by a LTB₄ receptor antagonist. These results suggest that arachidonic acid conversion to LTB₄ following ICH contributes to neuroinflammation and ensuing neural tissue damage by inducing microglial activation and neutrophil recruitment.

MiRNA-494 enhances M1 macrophage polarization via Nrdp1 in ICH mice model

Background

Ubiquitination-mediated M1/M2 macrophage polarization plays important roles in the pathogenesis of immune disease. However, the regulatory mechanism of ubiquitination during M1/M2 macrophage polarization following intracerebral hemorrhage (ICH) has not been well studied.

Methods

In the experiment, macrophages were administered with erythrocyte lysates, and then miR-494-, Nrdp1-, and M1/M2-related markers were analyzed. Brain inflammatory response, brain edema, and neurological functions of ICH mice were also assessed.

Results

We found that miR-494 levels increased while Nrdp1 levels decreased in macrophages after ICH. We also demonstrated that miR-494 inhibited Nrdp1 expression by directly binding its 3′-untranslated region. MiR-494 attenuated C/EBP-β activation and downstream proinflammatory factor production. Upregulation of Nrdp1 in macrophages significantly promoted M2 macrophage polarization via ubiquitinating and activating C/EBP-β. Moreover, the results indicated that miR-494 could enhance M1 macrophage polarization, promote brain edema, and impair neurological functions in ICH mice.

Conclusions

Taken together, our results demonstrated that Nrdp1 contributed to M1/M2 macrophage polarization and neuroinflammation via ubiquitination and activation of C/EBP-β in ICH. miR-494 may provide a promising therapeutic clue for ICH.

Cigarette Smoking History and Functional Outcomes After Spontaneous Intracerebral Hemorrhage

Background and Purpose- Although cigarette use may be a risk for intracerebral hemorrhage (ICH), animal models suggest that nicotine has a potential neuroprotective effect. The aim of this multicenter study is to determine the effect of smoking history on outcome in ICH patients. Methods- We analyzed prospectively collected data from the Ethnic/Racial Variations of Intracerebral Hemorrhage study and included patients with smoking status data in the analysis. Patients were dichotomized into nonsmokers versus ever-smokers, and the latter group was further categorized as former (>30 days before ICH) or current (≤30 days before ICH) smokers. The primary outcome was 90-day modified Rankin Scale score shift analysis. Secondary outcomes were in-hospital mortality and mortality, Barthel Index, and self-reported health status measures at 90 days. Results- The overall study cohort comprised 1509 nonsmokers and 1423 ever-smokers (841 former, 577 current, 5 unknown). No difference in primary outcome was observed between nonsmokers versus ever-smokers (adjusted odds ratio [aOR], 1.041; 95% CI, 0.904-1.199; P=0.577). No differences in primary outcome were observed between former (aOR, 0.932; 95% CI, 0.791-1.178; P=0.399) or current smokers (aOR, 1.178; 95% CI, 0.970-1.431; P=0.098) versus nonsmokers. Subgroup analyses by race/ethnicity demonstrated no differences in primary outcome when former and current smokers were compared with nonsmokers. Former, but not current, smokers had a lower in-hospital mortality rate (aOR, 0.695; 95% CI, 0.500-0.968; P=0.031), which was only observed in Hispanics (aOR, 0.533; 95% CI, 0.309-0.921; P=0.024). Differences in self-reported health status measures were only observed in whites. Conclusions- Cigarette smoking history does not seem to provide a beneficial effect on 90-day functional outcome in patients with ICH.

A Nurr1 agonist amodiaquine attenuates inflammatory events and neurological deficits in a mouse model of intracerebral hemorrhage

Inflammatory responses are considered to play pivotal roles in the pathogenesis of intracerebral hemorrhage (ICH). Here we show that a nuclear receptor Nurr1 (NR4A2) was expressed prominently in microglia/macrophages and astrocytes in the perihematomal region in the striatum of mice after ICH. Daily administration of a Nurr1 agonist amodiaquine (40 mg/kg, i.p.) from 3 h after ICH induction diminished perihematomal activation of microglia/macrophages and astrocytes. Amodiaquine also suppressed ICH-induced mRNA expression of IL-1β, CCL2 and CXCL2, and ameliorated motor dysfunction of mice. These results suggest that Nurr1 serves a novel target for ICH therapy.

Changes in motor function, cognition, and emotion-related behavior after right hemispheric intracerebral hemorrhage in various brain regions of mouse

Intracerebral hemorrhage (ICH) is a detrimental type of stroke. Mouse models of ICH, induced by collagenase or blood infusion, commonly target striatum, but not other brain sites such as ventricular system, cortex, and hippocampus. Few studies have systemically investigated brain damage and neurobehavioral deficits that develop in animal models of ICH in these areas of the right hemisphere. Therefore, we evaluated the brain damage and neurobehavioral dysfunction associated with right hemispheric ICH in ventricle, cortex, hippocampus, and striatum. The ICH model was induced by autologous whole blood or collagenase VII-S (0.075 units in 0.5 µl saline) injection. At different time points after ICH induction, mice were assessed for brain tissue damage and neurobehavioral deficits. Sham control mice were used for comparison. We found that ICH location influenced features of brain damage, microglia/macrophage activation, and behavioral deficits. Furthermore, the 24-point neurologic deficit scoring system was most sensitive for evaluating locomotor abnormalities in all four models, especially on days 1, 3, and 7 post-ICH. The wire-hanging test was useful for evaluating locomotor abnormalities in models of striatal, intraventricular, and cortical ICH. The cylinder test identified locomotor abnormalities only in the striatal ICH model. The novel object recognition test was effective for evaluating recognition memory dysfunction in all models except for striatal ICH. The tail suspension test, forced swim test, and sucrose preference test were effective for evaluating emotional abnormality in all four models but did not correlate with severity of brain damage. These results will help to inform future preclinical studies of ICH outcomes.

Intracerebral Hemorrhage as an Axonal Tract Injury Disorder with Inflammatory Reactions

Intracerebral hemorrhage (ICH) is a neurological disorder frequently accompanied by severe dysfunction. Critical pathogenic events leading to poor prognosis should be identified for the development of novel effective therapies for ICH. Here we focus on the injury of the axonal tract, particularly of the internal capsule, with reference to its contribution to ICH pathology and potential therapeutic interventions in addition to its cellular mechanisms. Studies on human ICH patients and rodent models of ICH suggest that invasion of hematoma into the internal capsule greatly worsens the severity of post-ICH symptoms. A blood-derived protease thrombin may play an important role in the acute phase of axonal tract injury in the internal capsule that includes compromised axonal transport and fragmentation of axonal structures. Several agents such as clioquinol, melatonin and Am80 (a retinoic acid receptor agonist) have been shown to produce therapeutic effects on rodent models of ICH associated with injury of the internal capsule. In the course of examinations on the effect of Am80, we obtained evidence for the involvement of CXCL2, a neutrophil chemotactic factor, in the pathogenesis of ICH. Accordingly, we also refer to the potential roles of infiltrating neutrophils and inflammatory responses in axonal tract injury and resultant neurological dysfunction in ICH.