Ingested Ketone Ester Leads to a Rapid Rise of Acetyl-CoA and Competes with Glucose Metabolism in the Brain of Non-Fasted Mice

International audienceThe role of ketone bodies in the cerebral energy homeostasis of neurological diseases has begun to attract recent attention particularly in acute neurological diseases. In ketogenic therapies, ketosis is achieved by either a ketogenic diet or by the administration of exogenous ketone bodies. The oral ingestion of the ketone ester (KE), (R)-3-hydroxybutyl (R)-3-hydroxybutyrate, is a new method to generate rapid and significant ketosis (i.e., above 6 mmol/L) in humans. KE is hydrolyzed into β-hydroxybutyrate (βHB) and its precursor 1,3-butanediol. Here, we investigate the effect of oral KE administration (3 mg KE/g of body weight) on brain metabolism of non-fasted mice using liquid chromatography in tandem with mass spectrometry. Ketosis (Cmax = 6.83 ± 0.19 mmol/L) was obtained at Tmax = 30 min after oral KE-gavage. We found that βHB uptake into the brain strongly correlated with the plasma βHB concentration and was preferentially distributed in the neocortex. We showed for the first time that oral KE led to an increase of acetyl-CoA and citric cycle intermediates in the brain of non-fasted mice. Furthermore, we found that the increased level of acetyl-CoA inhibited glycolysis by a feedback mechanism and thus competed with glucose under physiological conditions. The brain pharmacodynamics of this oral KE strongly suggest that this agent should be considered for acute neurological diseases

Association of Posterior Reversible Encephalopathy Syndrome and Transient Apical Ballooning Syndrome (Takotsubo): First Case Report of a Man and Review of the Literature

Introduction: An association of posterior reversible encephalopathy syndrome (PRES) and takotsubo is rare. We present the first case of a male patient. Case Report: A 69-year-old man presented to the hospital in a persistent comatose state following a generalized tonic-clonic seizure with high blood pressure. The electrocardiogram revealed transient left bundle branch block. Troponin and BNP were elevated. Cardiac ultrasound showed large apical akinesia with altered left ventricular ejection fraction, and the left ventriculogram showed characteristic regional wall motion abnormalities involving the mid and apical segments. Brain MRI showed bilateral, cortical, and subcortical vasogenic edema predominant in the posterior right hemisphere. The lumbar puncture and cerebral angiography were normal. Paraclinical abnormalities were reversible within 2 weeks with a clinical recovery in 3 months, confirming the takotsubo and the PRES diagnoses. Discussion: Several theories hypothesize the underlying pathophysiology of takotsubo or PRES. Circulating catecholamines are up to 3 times higher in patients with takotsubo causing impaired microcirculation and apical hypokinesia. An association of both takotsubo and asthma crisis and PRES and asthma crisis underlines the role of catecholamines in the occurrence of these disorders. Conclusion: Early recognition of this rare association, in which heart and neurological damage may require rapid intensive care support, is needed

Effect of hyperglycemia on stroke outcome is not homogeneous to all patients treated with mechanical thrombectomy

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Diabetes is an Independent Growth Factor of Ischemic Stroke During Reperfusion Phase Leading to Poor Clinical Outcome

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Metabolome of Cerebral Thrombi Reveals an Association between High Glycemia at Stroke Onset and Good Clinical Outcome

Despite the fact that glucose is the main fuel of the brain, hyperglycemia at hospital admission is generally associated with a poor functional outcome in stroke patients. This paradox may be explained by the lack of information about the blood glucose level at stroke onset. Here, we analyzed the metabolome of blood cells entrapped in cerebral thrombi to gain insight into their metabolism at stroke onset. Fourty-one consecutive stroke patients completely recanalized by mechanical thrombectomy within 6 h were included. The metabolome of retrieved thrombi was analyzed by liquid chromatography tandem with mass spectrometry. Discriminant Analysis (sparse Partial Least Squares Discriminant Analysis (sPLS-DA)) was performed to identify classification models and significant associated features of favorable clinical outcome at 3 months (modified Rankin Scale (mRS) < 2). sPLS-DA of the metabolomes of cerebral thrombi discriminated between stroke patients with a favorable or poor clinical outcome (Area Under the Curve (AUC) = 0.992 (0.931–1)). In addition, our results revealed that high sorbitol and glucose levels in the thrombi positively correlated with favorable clinical outcomes. Sorbitol, a short-term glycemic index reflecting a high blood glucose level at stroke onset, was found to be an independent predictor of good outcome (AUC = 0.908 (0.807–0.995)). This study demonstrates that a high blood glucose level at stroke onset is beneficial to the clinical outcome of the patient

Atrial Fibrillation Detected by Implantable Monitor in Embolic Stroke of Undetermined Source: A New Clinical Entity

International audienceBackground: High incidence of covert paroxysmal atrial fibrillation (CPAF) detected by an implantable cardiac monitor (ICM) is expected in embolic stroke of undetermined source (ESUS) patients. This study aimed to determine the CPAF rate in an ESUS cohort using ICMs and compare stroke characteristics of patients with CPAF to those with known or inpatient-diagnosed AF (KIDAF). Methods: ESUS patients with ICMs were enrolled. ESUS diagnosis was defined as a non-lacunar stroke in the absence of symptomatic atherosclerotic stenosis (≥50%), no major-risk cardioembolic source, and no other specific cause. ESUS characteristics of patients with CPAF were compared to ESUS patients without CPAF and to KIDAF stroke patients. Results: During the median follow-up of 476 (371–615) days, CPAF was newly detected in 38/163 (23.31%) patients within 236 (115.50–510.75) days after the stroke. CPAF was independently associated to older age, coronaropathy, left atrial dilation, and atrial hyperexcitability, but not to stroke severity. Compared to KIDAF strokes, ESUS with CPAF had lower rates of proximal occlusion leading to milder clinical severity (NIHSS: 3.00 (1.00–8.25) vs. 14.50 (6.00–21.00)). Conclusions: Our study revealed a high proportion of CPAF in ESUS. We highlight that CPAF is a distinct clinical entity compared to KIDAF based on differences in stroke characteristics and AF diagnosis temporality

Hypoperfusion of the thalamus is associated with disability in relapsing remitting multiple sclerosis

International audienceBACKGROUND: While gray matter (GM) perfusion abnormalities have been evidenced in multiple sclerosis (MS) patients, the relationships with disability still remain unclear. Considering that atrophy is known to impact on perfusion, we aimed to assess perfusion abnormalities in GM of MS patients, outside atrophic regions and investigate relationships with disability. METHODS: Brain perfusion of 23 relapsing remitting MS patients and 16 matched healthy subjects were assessed at 3T using the pseudo-continuous arterial spin labeling magnetic resonance imaging technique. In order to locate potential GM perfusion abnormalities in regions spared by atrophy, we combined voxelwise comparisons of GM cerebral blood flow (CBF) maps (cortex and deep GM) (P\textless0.005, FWE-corrected) and voxel-based-morphometry analysis (P\textless0.005, FDR-corrected) to exclude atrophic regions. Disability was assessed using the Expanded Disability Status Scale (EDSS) and the Multiple Sclerosis Functional Composite score (MSFC). RESULTS: In patients, significant GM hypoperfusion outside atrophic regions was depicted only in bilateral thalami. No other cluster was found to be hypoperfused compared to controls. Perfusion of thalami was correlated to MSFC (P=0.011, rho=0.523). A trend of correlation was found between perfusion of thalami and EDSS (P=0.061, rho=-0.396). CONCLUSION: In relapsing remitting MS, perfusion abnormalities in thalamic regions contribute to disability. These findings suggest that functional impairments of thalami, representing a major brain hub, may disturb various cerebral functions even before structural damage

Intracranial haemorrhage in infective endocarditis

International audienceBackground.-Although intracranial cerebral haemorrhage (ICH) complicating infective endo-carditis (IE) is a critical clinical issue, its characteristics, impact, and prognosis remain poorly known. Aims.-To assess the incidence, mechanisms, risk factors and prognosis of ICH complicating left-sided IE. Abbreviations: ICH, intracranial cerebral haemorrhage; IE, infective endocarditis; TOE, transoesophageal echocardiography; TTE, transthoracic echocardiography