Acute ischaemic stroke in active cancer versus non-cancer patients: stroke characteristics, mechanisms and clinical outcomes.

BACKGROUND AND PURPOSE: Demographics, clinical characteristics, stroke mechanisms and long-term outcomes were compared between acute ischaemic stroke (AIS) patients with active cancer (AC) versus non-cancer patients. METHODS: Using data from 2003 to 2021 in the Acute STroke Registry and Analysis of Lausanne, a retrospective cohort study was performed comparing patients with AC, including previously known and newly diagnosed cancers, with non-cancer patients. Patients with inactive cancer were excluded. Outcomes were the modified Rankin Scale (mRS) score at 3 months, death and cerebrovascular recurrences at 12 months before and after propensity score matching. RESULTS: Amongst 6686 patients with AIS, 1065 (15.9%) had a history of cancer. After excluding 700 (10.4%) patients with inactive cancer, there were 365 (5.5%) patients with AC and 5621 (84%) non-cancer AIS patients. Amongst AC patients, 154 (42.2%) strokes were classified as cancer related. In multivariable analysis, patients with AC were older (adjusted odds ratio [aOR] 1.02, 95% confidence interval [CI] 1.00-1.03), had fewer vascular risk factors and were 48% less likely to receive reperfusion therapies (aOR 0.52, 95% CI 0.35-0.76). Three-month mRS scores were not different in AC patients (aOR 2.18, 95% CI 0.96-5.00). At 12 months, death (adjusted hazard ratio 1.91, 95% CI 1.50-2.43) and risk of cerebrovascular recurrence (sub-distribution hazard ratio 1.68, 95% CI 1.22-2.31) before and after propensity score matching were higher in AC patients. CONCLUSIONS: In a large institutional registry spanning nearly two decades, AIS patients with AC had less past cerebrovascular disease but a higher 1-year risk of subsequent death and cerebrovascular recurrence compared to non-cancer patients. Antithrombotic medications at discharge may reduce this risk in AC patients.

Ischemic Stroke in Cancer: Mechanisms, Biomarkers, and Implications for Treatment.

Ischemic stroke is an important cause of morbidity and mortality in cancer patients. The underlying mechanisms linking cancer and stroke are not completely understood. Long-standing and more recent evidence suggests that cancer-associated prothrombotic states, along with treatment-related vascular toxicity, such as with chemotherapy and immunotherapy, contribute to an increased risk of ischemic stroke in cancer patients. Novel biomarkers, including coagulation, platelet and endothelial markers, cell-free DNA, and extracellular vesicles are being investigated for their potential to improve risk stratification and patient selection for clinical trials and to help guide personalized antithrombotic strategies. Treatment of cancer-related stroke poses unique challenges, including the need to balance the risk of recurrent stroke and other thromboembolic events with that of bleeding associated with antithrombotic therapy. In addition, how and when to restart cancer treatment after stroke remains unclear. In this review, we summarize current knowledge on the mechanisms underlying ischemic stroke in cancer, propose an etiological classification system unique to cancer-related stroke to help guide patient characterization, provide an overview of promising biomarkers and their clinical utility, and discuss the current state of evidence-based management strategies for cancer-related stroke. Ultimately, a personalized approach to stroke prevention and treatment is required in cancer patients, considering both the underlying cancer biology and the individual patient's risk profile.

Genomic and transcriptomic advances in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder and the most common motor neuron disease. ALS shows substantial clinical and molecular heterogeneity. In vitro and in vivo models coupled with multiomic techniques have provided important contributions to unraveling the pathomechanisms underlying ALS. To date, despite promising results and accumulating knowledge, an effective treatment is still lacking. Here, we provide an overview of the literature on the use of genomics, epigenomics, transcriptomics and microRNAs to deeply investigate the molecular mechanisms developing and sustaining ALS. We report the most relevant genes implicated in ALS pathogenesis, discussing the use of different high-throughput sequencing techniques and the role of epigenomic modifications. Furthermore, we present transcriptomic studies discussing the most recent advances, from microarrays to bulk and single-cell RNA sequencing. Finally, we discuss the use of microRNAs as potential biomarkers and promising tools for molecular intervention. The integration of data from multiple omic approaches may provide new insights into pathogenic pathways in ALS by shedding light on diagnostic and prognostic biomarkers, helping to stratify patients into clinically relevant subgroups, revealing novel therapeutic targets and supporting the development of new effective therapies.

IV Thrombolysis With or Without Endovascular Treatment for Suspected Ischemic Stroke in Patients With Intracranial Tumors.

BACKGROUND AND OBJECTIVES: IV thrombolysis (IVT) for suspected ischemic stroke in patients with intracranial neoplasms is off-label. However, data on risks of intracranial hemorrhage (ICH) are scarce. METHODS: In a multicenter registry-based analysis within the European Thrombolysis in Ischemic Stroke Patients (TRISP) collaboration, we assessed frequencies of symptomatic and fatal ICH after IVT for suspected ischemic stroke in patients with intracranial tumors by descriptive statistics and analyzed associations with clinical and imaging characteristics by binary logistic regression. Definition of symptomatic ICH was based on the clinical criteria of the European Cooperative Acute Stroke-II trial including hemorrhage at any site in cranial imaging and concurrent clinical deterioration. RESULTS: Screening data of 21,289 patients from 14 centers, we identified 105 patients receiving IVT; among them were 29 patients (28%) with additional endovascular treatment, with suspected, that is, imaging-based, or histologically confirmed diagnosis of intracranial tumors. Among 104 patients with CT or MRI after IVT available, symptomatic and fatal ICH were observed in 9 and 4 patients (9% and 4%, respectively). Among 82 patients with suspected or confirmed meningioma, symptomatic and fatal ICH occurred in 6 and 3 patients (7% and 4%), respectively. In 18 patients with intra-axial suspected or confirmed primary or secondary brain tumors, there was 1 symptomatic nonfatal ICH (6%). Of 4 patients with tumors of the pituitary region, 2 patients (50%) had symptomatic ICH including 1 fatal ICH (25%). Tumor size was not associated with the occurrence of symptomatic ICH (odds ratio 2.8, 95% CI 0.3-24.8, p = 0.34). DISCUSSION: In our dataset from routine clinical care, we provide insights on the safety of IVT for suspected ischemic stroke in patients with intracranial tumors, a population that is commonly withheld thrombolysis in clinical practice and prospective trials. Except for a potential high risk of symptomatic ICH after IVT in patients with tumors of the pituitary region, frequencies of symptomatic ICH in patients with intracranial tumors in our cohort seem to be in the upper range of rates observed in previous studies within the TRISP cooperation. These results may guide individual treatment decisions in patients with acute stroke and intracranial tumors with potential benefit of IVT.

Clinical and Demographic Characteristics, Mechanisms, and Outcomes in Patients With Acute Ischemic Stroke and Newly Diagnosed or Known Active Cancer.

BACKGROUND AND OBJECTIVES: Patients with a new diagnosis of cancer carry an increased risk of acute ischemic stroke (AIS), and this risk varies depending on age, cancer type, stage, and time from diagnosis. Whether patients with AIS with a new diagnosis of neoplasm represent a distinct subset from those with a previously known active malignancy remains unclear. We aimed to estimate the rate of stroke in patients with newly diagnosed cancer (NC) and previously known active cancer (KC) and to compare the demographic and clinical features, stroke mechanisms, and long-term outcomes between groups. METHODS: Using 2003-2021 data from the Acute STroke Registry and Analysis of Lausanne registry, we compared patients with KC with patients with NC (cancer identified during AIS hospitalization or within the following 12 months). Patients with inactive and no history of cancer were excluded. Outcomes were the modified Rankin scale (mRS) score at 3 months and mortality and recurrent stroke at 12 months. We used multivariable regression analyses to compare outcomes between groups while adjusting for important prognostic variables. RESULTS: Among 6,686 patients with AIS, 362 (5.4%) had active cancer (AC), including 102 (1.5%) with NC. Gastrointestinal and genitourinary cancers were the most frequent cancer types. Among all patients with AC, 152 (42.5%) AISs were classified as cancer related, with nearly half of these cases attributed to hypercoagulability. In multivariable analysis, patients with NC had less prestroke disability (adjusted odds ratio [aOR] 0.62, 95% CI 0.44-0.86) and fewer prior stroke/transient ischemic attack events (aOR 0.43, 95% CI 0.21-0.88) than patients with KC. Three-month mRS scores were similar between cancer groups (aOR 1.27, 95% CI 0.65-2.49) and were predominantly driven by the presence of newly diagnosed brain metastases (aOR 7.22, 95% CI 1.49-43.17) and metastatic cancer (aOR 2.19, 95% CI 1.22-3.97). At 12 months, mortality risk was higher in patients with NC vs patients with KC (hazard ratio [HR] 2.11, 95% CI 1.38-3.21), while recurrent stroke risk was similar between groups (adjusted HR 1.27, 95% CI 0.67-2.43). DISCUSSION: In a comprehensive institutional registry spanning nearly 2 decades, 5.4% of patients with AIS had AC, a quarter of which were diagnosed during or within 12 months after the index stroke hospitalization. Patients with NC had less disability and prior cerebrovascular disease, but a higher 1-year risk of subsequent death than patients with KC.

Advancing Stroke Research on Cerebral Thrombi with Omic Technologies.

Cerebrovascular diseases represent a leading cause of disability, morbidity, and death worldwide. In the last decade, the advances in endovascular procedures have not only improved acute ischemic stroke care but also conceded a thorough analysis of patients' thrombi. Although early anatomopathological and immunohistochemical analyses have provided valuable insights into thrombus composition and its correlation with radiological features, response to reperfusion therapies, and stroke etiology, these results have been inconclusive so far. Recent studies applied single- or multi-omic approaches-such as proteomics, metabolomics, transcriptomics, or a combination of these-to investigate clot composition and stroke mechanisms, showing high predictive power. Particularly, one pilot studies showed that combined deep phenotyping of stroke thrombi may be superior to classic clinical predictors in defining stroke mechanisms. Small sample sizes, varying methodologies, and lack of adjustments for potential confounders still represent roadblocks to generalizing these findings. However, these techniques hold the potential to better investigate stroke-related thrombogenesis and select secondary prevention strategies, and to prompt the discovery of novel biomarkers and therapeutic targets. In this review, we summarize the most recent findings, overview current strengths and limitations, and present future perspectives in the field.

Bridging the Gap: Gene Therapy in a Patient With Spinal Muscular Atrophy Type 1.

Molecular therapies exploit the understanding of pathogenic mechanisms to reconstitute impaired gene function or manipulate flawed RNA expression. These therapies include (1) RNA interference by antisense oligonucleotides, (2) mRNA modification using small molecules, and (3) gene replacement therapy, the viral-mediated intracellular delivery of exogenous nucleic acids to reverse a genetic defect. Several molecular therapies are approved for treating spinal muscular atrophy (SMA), a recessive genetic disorder caused by survival motor neuron (SMN)1 gene alterations. SMA involves degeneration of lower motor neurons, which leads to progressive muscle weakness, hypotonia, and hypotrophy. Onasemnogene abeparvovec is a gene replacement therapy for SMA that uses adeno-associated virus delivery of functional SMN1 cDNA to motor neurons. Two other molecular therapies modulate SMN2 transcription: nusinersen, an antisense oligonucleotide, and risdiplam, a small molecule designed to modify faulty mRNA expression. The most suitable individualized treatment for SMA is not established. Here, we describe remarkable clinical improvement in a 4-month-old patient with SMA type 1 who received onasemnogene abeparvovec therapy. This case represents an explanatory bridge from bench to bedside with regard to therapeutic approaches for genetic disorders in neurology. Knowledge of the detailed mechanisms underlying genetic neurologic disorders, particularly monogenic conditions, is paramount for developing tailored therapies. When multiple disease-modifying therapies are available, early genetic diagnosis is crucial for appropriate therapy selection, highlighting the importance of early identification and intervention. A combination of drugs, each targeting unique genetic pathomechanisms, may provide additional clinical benefits.

Newly Diagnosed Hepatic Encephalopathy Presenting as Non-convulsive Status Epilepticus: A Case Report and Literature Review.

Background: Hepatic encephalopathy is characterized by psychiatric and neurological abnormalities, including epileptic seizure and non-convulsive and convulsive status epilepticus. Conventional brain magnetic resonance imaging is useful in supporting diagnosis since it can reveal specific radiological findings. In the literature, there is no description of hepatic encephalopathy onset as non-convulsive status epilepticus; we provide the first report. Case Summary: We report a case of a 67-year-old woman, without history of cirrhosis, presenting altered mental state, normal brain computed tomography imaging, and electroencephalography suggestive of epileptic activity. We suspected non-convulsive status epilepticus, and we administered diazepam and levetiracetam with clinical improvement. Thus, we made a diagnosis of non-convulsive status epilepticus. A radiological study with brain magnetic resonance imaging showed bilateral hyperintensity on T1-weighted sequences of globus pallidus and hyperintensity of both corticospinal tracts on T2-weighted fluid-attenuated inversion recovery sequences. Blood tests revealed hyperammonemia, mild abnormality of liver function indices, and chronic Hepatitis B and D virus coinfection. Hepatic elastosonography suggested liver cirrhosis. The patient started antiviral therapy with entecavir and prevention of hepatic encephalopathy with rifaximin and lactulose; she was discharged with a normal mental state. Conclusions: Hepatic encephalopathy can present as an initial manifestation with non-convulsive status epilepticus. Electroencephalography is useful for differentiating non-convulsive status epilepticus from an episode of hepatic encephalopathy, and neuroimaging aids the diagnostic process.

Impact of COVID-19 on the quality of life of patients with neuromuscular disorders in the Lombardy area, Italy.

INTRODUCTION: /AIMS: Patients with neuromuscular disorders (NMDs), including many elderly, immunosuppressed, and disabled individuals, may have been particularly affected during the coronavirus disease 2019 (COVID-19) pandemic in Lombardy, a COVID-19 high-incidence area between February and May 2020. We aimed to evaluate the effects of the COVID-19 pandemic on the quality of life (QoL) and perceived disease burden of this group of patients. METHODS: We conducted a cross-sectional phone-based survey study between June 1 and June 14, 2020, on a sample of 240 NMD patients followed at our clinic in Milan, Italy. We asked about perceived NMD burden and QoL before and during the COVID-19 pandemic. We collected responses on access to outpatient care and ancillary services. We investigated the presence of symptoms suggestive of COVID-19 infection and confirmed cases. RESULTS: We collected 205 responses: 53 patients (25.9%) reported a subjective worsening of the underlying NMD. QoL measures showed a significant worsening between pre and pandemic time frames (odds ratio, 2.14 95%; confidence interval, 1.82-2.51). Outpatient visits were postponed in more than half of cases (57.1%), with 104 patients (50.7%) experiencing a cancellation of scheduled diagnostic tests. 79 patients (38.5%) reported at least one symptom attributable to COVID-19 infection. Among the 10 patients tested with nasopharyngeal swabs, 6 tested positive and 3 died from respiratory failure, including 2 patients on corticosteroid/ immunosuppressive therapy. DISCUSSION: The COVID-19 pandemic affected QoL and limited access to outpatient care and ancillary services of NMD patients in Lombardy between February and May 2020.

Advancing Drug Discovery for Neurological Disorders Using iPSC-Derived Neural Organoids.

In the last decade, different research groups in the academic setting have developed induced pluripotent stem cell-based protocols to generate three-dimensional, multicellular, neural organoids. Their use to model brain biology, early neural development, and human diseases has provided new insights into the pathophysiology of neuropsychiatric and neurological disorders, including microcephaly, autism, Parkinson's disease, and Alzheimer's disease. However, the adoption of organoid technology for large-scale drug screening in the industry has been hampered by challenges with reproducibility, scalability, and translatability to human disease. Potential technical solutions to expand their use in drug discovery pipelines include Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) to create isogenic models, single-cell RNA sequencing to characterize the model at a cellular level, and machine learning to analyze complex data sets. In addition, high-content imaging, automated liquid handling, and standardized assays represent other valuable tools toward this goal. Though several open issues still hamper the full implementation of the organoid technology outside academia, rapid progress in this field will help to prompt its translation toward large-scale drug screening for neurological disorders.

Clinical features and disease course of patients with acute ischaemic stroke just before the Italian index case: Was COVID-19 already there?

Since the end of February 2020, Italy has suffered one of the most severe outbreaks of coronavirus disease 2019 (COVID-19). However, what happened just before the Italian index case has not yet been investigated. To answer this question, we evaluated the potential impact of COVID-19 on the clinical features of a cohort of neurological inpatients admitted right before the Italian index case, as compared to the same period of the previous year. Demographic, clinical, treatment and laboratory data were extracted from medical records. The data collected included all inpatients who had been admitted to the Neurology and Stroke Units of the Ospedale Maggiore Policlinico, Milan, Italy, from December 15, 2018 to February 20, 2019 and from December 15, 2019 to February 20, 2020. Of the 248 patients, 97 subjects (39.1%) were admitted for an acute cerebrovascular event: 46 in the 2018/2019 period (mean [SD] age, 72.3 [15.6] years; 22 men [47.8%]), and 51 in the 2019/2020 interval (mean [SD] age, 72.8 [12.4] years; 24 men [47.1%]). The number of cryptogenic strokes has increased during the 2019-2020 year, as compared to the previous year (30 [58.8%] vs. 18 [39.1%], p = 0.05). These patients had a longer hospitalization (mean [SD] day, 15.7 [10.5] days vs. mean [SD] day, 11.7 [7.2] days, p = 0.03) and more frequent cerebrovascular complications (9 [30.0%] vs. 2 [11.1%]), but presented a lower incidence of cardiocerebral risk factors (18 [60.0%] vs. 14 [77.8%]). Right before the Italian index case, an increase in cryptogenic strokes has occurred, possibly due to the concomitant COVID-19.

Management of patients with neuromuscular disorders at the time of the SARS-CoV-2 pandemic.

The novel Coronavirus disease-19 (COVID-19) pandemic has posed several challenges for neuromuscular disorder (NMD) patients. The risk of a severe course of SARS-CoV-2 infection is increased in all but the mildest forms of NMDs. High-risk conditions include reduced airway clearance due to oropharyngeal weakness and risk of worsening with fever, fasting or infection Isolation requirements may have an impact on treatment regimens administered in hospital settings, such as nusinersen, glucosidase alfa, intravenous immunoglobulin, and rituximab infusions. In addition, specific drugs for SARS-CoV2 infection under investigation impair neuromuscular function significantly; chloroquine and azithromycin are not recommended in myasthenia gravis without available ventilatory support and prolonged prone positioning may influence options for treatment. Other therapeutics may affect specific NMDs (metabolic, mitochondrial, myotonic diseases) and experimental approaches for Coronavirus disease 2019 may be offered "compassionately" only after consulting the patient's NMD specialist. In parallel, the reorganization of hospital and outpatient services may change the management of non-infected NMD patients and their caregivers, favouring at-distance approaches. However, the literature on the validation of telehealth in this subgroup of patients is scant. Thus, as the first wave of the pandemic is progressing, clinicians and researchers should address these crucial open issues to ensure adequate caring for NMD patients. This manuscript summarizes available evidence so far and provides guidance for both general neurologists and NMD specialists dealing with NMD patients in the time of COVID-19.

Hyperacute extensive spinal cord infarction and negative spine magnetic resonance imaging: a case report and review of the literature.

RATIONALE: Spinal cord infarction (SCI) accounts for only 1% to 2% of all ischemic strokes and 5% to 8% of acute myelopathies. Magnetic resonance imaging (MRI) holds a role in ruling out non-ischemic etiologies, but the diagnostic accuracy of this procedure may be low in confirming the diagnosis, even when extensive cord lesions are present. Indeed, T2 changes on MRI can develop over hours to days, thus accounting for the low sensitivity in the hyperacute setting (ie, within 6 hours from symptom onset). For these reasons, SCI remains a clinical diagnosis. Despite extensive diagnostic work-up, up to 20% to 40% of SCI cases are classified as cryptogenic. Here, we describe a case of cryptogenic longitudinally extensive transverse myelopathy due to SCI, with negative MRI and diffusion-weighted imaging at 9 hours after symptom onset. PATIENT CONCERNS: A 51-year-old woman presented to our Emergency Department with acute severe abdominal pain, nausea, vomiting, sudden-onset of bilateral leg weakness with diffuse sensory loss, and paresthesias on the trunk and legs. DIAGNOSES: On neurological examination, she showed severe paraparesis and a D6 sensory level. A 3T spinal cord MRI with gadolinium performed at 9 hours after symptom onset did not detect spinal cord alterations. Due to the persistence of a clinical picture suggestive of an acute myelopathy, a 3T MRI of the spine was repeated after 72 hours showing a hyperintense "pencil-like" signal mainly involving the grey matter from T1 to T6 on T2 sequence, mildly hypointense on T1 and with restricted diffusion. INTERVENTIONS: The patient was given salicylic acid (100 mg/d), prophylactic low-molecular-weight heparin, and began neuromotor rehabilitation. OUTCOMES: Two months later, a follow-up neurological examination revealed a severe spastic paraparesis, no evident sensory level, and poor sphincteric control with distended bladder. LESSONS: Regardless of its relatively low frequency in the general population, SCI should be suspected in every patient presenting with acute and progressive myelopathic symptoms, even in the absence of vascular risk factors. Thus, a clinical presentation consistent with a potential vascular syndrome involving the spinal cord overrides an initially negative MRI and should not delay timely and appropriate management.

Education Research: Effect of the COVID-19 pandemic on neurology trainees in Italy: A resident-driven survey.

OBJECTIVE: To assess the effect of the coronavirus disease 2019 (COVID-19) outbreak on neurology resident training in Italy. METHOD: We created a web-based survey regarding changes in clinical, research, and educational activity of neurology trainees in Italy during the COVID-19 pandemic and the preventive measures undertaken by local institutions to reduce the risk of contagion. RESULTS: Seventy-nine residents working in Italy completed the survey. A total of 87.3% of trainees reported a substantial reduction in their neurologic duties since COVID-19 appeared in Italy, and 17.8% were also recruited or volunteered for COVID-19-dedicated wards. Likewise, more than 60% of trainees experienced a reduction or interruption in research activity. As regards the perceived effect of the COVID-19 outbreak on their neurologic training, almost 70% of surveyed trainees believe that the COVID-19 pandemic had or will have a negative effect on their formation as neurologists, for different reasons. Furthermore, trainees reported a consistent exposure (69.6%) to confirmed positive COVID-19 cases at work, with divergent surveillance and preventive measures taken by local institutions. CONCLUSIONS: Overall, the survey shows that the COVID-19 pandemic in Italy has had a subjective negative effect on neurology residents on didactics, clinical, and research training as well as training abroad. The COVID-19 outbreak poses many challenges to academic institutions and training programs, and addressing these issues promptly is crucial to ensure continued quality of trainees' neurologic education. Sharing solutions and ideas among the international neurologic community might help neurology training programs worldwide to better counteract these problems.

Insights into disease mechanisms and potential therapeutics for C9orf72-related amyotrophic lateral sclerosis/frontotemporal dementia.

In 2011, a hexanucleotide repeat expansion (HRE) in the noncoding region of C9orf72 was associated with the most frequent genetic cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). The main pathogenic mechanisms in C9-ALS/FTD are haploinsufficiency of the C9orf72 protein and gain of function toxicity from bidirectionally-transcribed repeat-containing RNAs and dipeptide repeat proteins (DPRs) resulting from non-canonical RNA translation. Additionally, abnormalities in different downstream cellular mechanisms, such as nucleocytoplasmic transport and autophagy, play a role in pathogenesis. Substantial research efforts using in vitro and in vivo models have provided valuable insights into the contribution of each mechanism in disease pathogenesis. However, conflicting evidence exists, and a unifying theory still lacks. Here, we provide an overview of the recently published literature on clinical, neuropathological and molecular features of C9-ALS/FTD. We highlight the supposed neuronal role of C9orf72 and the HRE pathogenic cascade, mainly focusing on the contribution of RNA foci and DPRs to neurodegeneration and discussing the several downstream mechanisms. We summarize the emerging biochemical and neuroimaging biomarkers, as well as the potential therapeutic approaches. Despite promising results, a specific disease-modifying treatment is still not available to date and greater insights into disease mechanisms may help in this direction.

Oral Administration of miR-30d from Feces of MS Patients Suppresses MS-like Symptoms in Mice by Expanding Akkermansia muciniphila.

Fecal transfer from healthy donors is being explored as a microbiome modality. MicroRNAs (miRNAs) have been found to affect the microbiome. Multiple sclerosis (MS) patients have been shown to have an altered gut microbiome. Here, we unexpectedly found that transfer of feces harvested at peak disease from the experimental autoimmune encephalomyelitis (EAE) model of MS ameliorates disease in recipients in a miRNA-dependent manner. Specifically, we show that miR-30d is enriched in the feces of peak EAE and untreated MS patients. Synthetic miR-30d given orally ameliorates EAE through expansion of regulatory T cells (Tregs). Mechanistically, miR-30d regulates the expression of a lactase in Akkermansia muciniphila, which increases Akkermansia abundance in the gut. The expanded Akkermansia in turn increases Tregs to suppress EAE symptoms. Our findings report the mechanistic underpinnings of a miRNA-microbiome axis and suggest that the feces of diseased subjects might be enriched with miRNAs with therapeutic properties.

iPSCs-Based Neural 3D Systems: A Multidimensional Approach for Disease Modeling and Drug Discovery.

Induced pluripotent stem cells (iPSCs)-based two-dimensional (2D) protocols have offered invaluable insights into the pathophysiology of neurological diseases. However, these systems are unable to reproduce complex cytoarchitectural features, cell-cell and tissue-tissue interactions like their in vivo counterpart. Three-dimensional (3D)-based culture protocols, though in their infancy, have offered new insights into modeling human diseases. Human neural organoids try to recapitulate the cellular diversity of complex tissues and can be generated from iPSCs to model the pathophysiology of a wide spectrum of pathologies. The engraftment of iPSCs into mice models and the improvement of differentiation protocols towards 3D cultures has enabled the generation of more complex multicellular systems. Consequently, models of neuropsychiatric disorders, infectious diseases, brain cancer and cerebral hypoxic injury can now be investigated from new perspectives. In this review, we consider the advancements made in modeling neuropsychiatric and neurological diseases with iPSC-derived organoids and their potential use to develop new drugs.