Circulating biomarkers in familial cerebral cavernous malformation

BACKGROUND

Cerebral Cavernous Malformation (CCM) is a rare cerebrovascular disease, characterized by the presence of multiple vascular malformations that may result in intracerebral hemorrhages (ICHs), seizure(s), or focal neurological deficits (FND). Familial CCM (fCCM) is due to loss of function mutations in one of the three independent genes KRIT1 (CCM1), Malcavernin (CCM2), or Programmed Cell death 10 (PDCD10/CCM3). The aim of this study was to identify plasma protein biomarkers of fCCM to assess the severity of the disease and predict its progression.

METHODS

Here, we have investigated plasma samples derived from n = 71 symptomatic fCCM patients (40 female/31 male) and n = 17 healthy donors (HD) (9 female/8 male) of the Phase 1/2 Treat_CCM trial, using multiplexed protein profiling approaches.

FINDINGS

Biomarkers as sCD14 (p = 0.00409), LBP (p = 0.02911), CXCL4 (p = 0.038), ICAM-1 (p = 0.02013), ANG2 (p = 0.026), CCL5 (p = 0.00403), THBS1 (p = 0.0043), CRP (p = 0.0092), and HDL (p = 0.027), were significantly different in fCCM compared to HDs. Of note, sENG (p = 0.011), THBS1 (p = 0.011) and CXCL4 (p = 0.011), were correlated to CCM genotype. sROBO4 (p = 0.014), TM (p = 0.026) and CRP (p = 0.040) were able to predict incident adverse clinical events, such as ICH, FND or seizure. GDF-15, FLT3L, CXCL9, FGF-21 and CDCP1, were identified as predictors of the formation of new MRI-detectable lesions over 2-year follow-up. Furthermore, the functional relevance of ang2, thbs1, robo4 and cdcp1 markers was validated by zebrafish pre-clinical model of fCCM.

INTERPRETATION

Overall, our study identifies a set of biochemical parameters to predict CCM progression, suggesting biological interpretations and potential therapeutic approaches to CCM disease.

FUNDING

Italian Medicines Agency, Associazione Italiana per la Ricerca sul Cancro (AIRC), ERC, Leducq Transatlantic Network of Excellence, Swedish Research Council.

Propranolol for familial cerebral cavernous malformation (Treat_CCM): study protocol for a randomized controlled pilot trial

Background

Cerebral cavernous malformations (CCMs) are vascular malformations characterized by clusters of enlarged leaky capillaries in the central nervous system. They may result in intracranial haemorrhage, epileptic seizure(s), or focal neurological deficits, and potentially lead to severe disability. Globally, CCMs represent the second most common intracranial vascular malformation in humans, and their familial form (FCCMs) accounts for one-fifth of cases. Neurosurgical excision, and perhaps stereotactic radiosurgery, is the only available therapeutic option. Case reports suggest that propranolol might modify disease progression.

Methods

Treat_CCM is a prospective, randomized, open-label, blinded endpoint (PROBE), parallel-group trial involving six Italian clinical centres with central reading of brain magnetic resonance imaging (MRI) and adverse events. Patients with symptomatic FCCMs are randomized (2:1 ratio) either to propranolol (40–80 mg twice daily) in addition to standard care or to standard care alone (i.e. anti-epileptic drugs or headache treatments). The primary outcome is intracranial haemorrhage or focal neurological deficit attributable to CCMs. The secondary outcomes are MRI changes over time (i.e. de novo CCM lesions, CCM size and signal characteristics, iron deposition, and vascular leakage as assessed by quantitative susceptibility mapping and dynamic contrast enhanced permeability), disability, health-related quality of life, depression severity, and anxiety (SF-36, BDI-II, State-Trait Anxiety Inventory).

Discussion

Treat_CCM will evaluate the safety and efficacy of propranolol for CCMs following promising case reports in a randomized controlled trial. The direction of effect on the primary outcome and the consistency of effects on the secondary outcomes (even if none of them yield statistically significant differences) of this external pilot study may lead to a larger sample size in a definitive phase 2 trial.

Trial registration

ClinicalTrails.gov, NCT03589014. Retrospectively registered on 17 July 2018.

Defective Fibrinolytic Response in Atherosclerotic Patients – Effect of lloprost and Its Possible Mechanism of Action

Plasma fibrinolytic activity and tissue-type plasminogen activator (t-PA) were defective in response to venous stasis in five out of ten patients with peripheral occlusive artery disease. Discontinuous infusions of iloprost, a stable synthetic analogue of prostacyclin, restored a normal fibrinolytic response in all five patients but did not induce a parallel increase of plasma t-PA. These findings suggest that in addition to the possible benefits due to its vasodilatory and antiplatelet activity, iloprost may improve the fibrinolytic activity in patients with atherosclerotic disease, providing them with further antithrombotic protection. The profibrinolytic effect of iloprost seems not to depend on its ability to induce vascular t-PA release. Rather, it might be related to its inhibitory effect on PAI release from platelets, endothelial cells and/or hepatocytes. Venous occlusion test represents an easy diagnostic approach to fibrinolytic defects, even if related to arterial disease, and may help select patients who need therapeutic intervention.

Cerebrovascular reactivity by quantitative magnetic resonance angiography with a Co₂ challenge. Validation as a new imaging biomarker

Assessment of cerebrovascular reactivity (CVR) is essential in cerebrovascular diseases, as exhausted CVR may enhance the risk of cerebral ischemic events. Transcranial Doppler (TCD) with a vasodilatory stimulus is currently used for CVR evaluation. Scanty data are available for Quantitative Magnetic Resonance Angiography (QMRA), which supplies higher spatial resolution and quantitative cerebral blood flow values. Aims of our pilot study were: (a) to assess safety and feasibility of CO2 administration during QMRA, (b) evaluation of CVR under QMRA compared to TCD, and (c) quantitative evaluation of blood flow from the major intracranial arterial vessels both at rest and after CO2. CVR during 5% CO2 air breathing was measured with TCD as a reference method and compared with QMRA. Fifteen healthy subjects (age 60.47 ± 2.24; male 11/15) were evaluated at rest and during CO2 challenge. Feasibility and safety of QMRA under CO2 were ensured in all subjects. CVR from middle cerebral artery territory was not statistically different between TCD and MRI (p>0.05). Mean arterial pressure (MAP) and heart rate (HR) increased during QMRA and TCD (MAP p=0.007 and p=0.001; HR p=0.043 and p=0.068, respectively). Blood flow values from all intracranial vessels increased after CO2 inhalation (p<0.001). CO2 administration during QMRA sessions is safe and feasible. Good correlation in terms of CVR was obtained comparing TCD and QMRA. Blood flow values significantly increased from all intracranial arterial vessels after CO2. Studies regarding CVR in physiopathological conditions might consider the utilization of QMRA both in routine clinical settings and in research projects.

An Effect of the PAI-1 4G/5G Polymorphism on Cholesterol Levels May Explain Conflicting Associations with Myocardial Infarction and Stroke

BACKGROUND AND PURPOSE

The gene-encoding plasminogen activator inhibitor type 1 (PAI-1) has a common 4G/5G 'functional' polymorphism, and people homozygous for the 4G allele have higher PAI-1 plasma concentrations. The 4G/4G genotype is associated with increased risk of myocardial infarction but paradoxically protects against stroke. We hypothesized that this paradox may be explained via an effect of the PAI-1 polymorphism on plasma lipids.

METHODS

We studied 71 consecutive Italian patients referred to our Institute for first stroke or vascular cognitive impairment. PAI-1 gene 4G/5G polymorphism, total plasma cholesterol, plasma triglycerides, sex, age, smoking, oral contraceptive use, statin therapy, hypertension, diabetes, and history of myocardial infarction were examined.

RESULTS

The 4G/4G genotype was significantly associated with high cholesterol (p = 0.003) but not with triglycerides (p = 0.39). Adjusted odds ratios were: 5.8 for 4G/4G vs. 4G/5G (95% CI, 3.1-23.0), and 15.9 for 4G/4G vs. 5G/5G (95% CI, 2.4-105.0).

CONCLUSIONS

This finding may explain the involvement of the PAI-1 polymorphism in the clustering of atherothrombotic risk factors, and why people with the 4G/4G genotype are at increased risk for myocardial infarction. Stroke is not so clearly related to hypercholesterolemia and other effects of the 4G/4G genotype (perhaps increased PAI-1 expression) may protect against stroke.

Cigarette smoking and risk of cerebral sinus thrombosis in oral contraceptive users: a case-control study

Idiopathic cerebral sinus thrombosis (CST) can cause death and serious neurological disability. It is unknown whether smoking, a major risk factor for arterial stroke, is a risk factor also for CST. This work explored the association between smoking and CST in a hospital-based, multicentric, case-control study. In order to avoid the confounding effect of the different risk factors for CST, we analysed the homogeneous subgroup of oral contraceptive users. We compared the prevalence of smoking in a group of 43 young women with CST (cases), whose oral contraceptive use was the only known risk factor, with a sample of 255 healthy contraceptive users of similar age (controls). The prevalence of smoking in cases and controls was similar (26% vs. 29%). The age and geographic area-adjusted odds ratio was 0.9; 95% confidence interval, 0.4-1.8; p=0.7. Smoking in oral contraceptive users does not appear to be associated with CST.

Wallerian degeneration of the pontocerebellar fibers

Two cases of pontine infarct with Wallerian degeneration (WD) of the pontocerebellar fibers are described. WD of pontocerebellar fibers, seen bilaterally along the transverse pontine fibers, is more visible in the middle cerebellar peduncles and extends into the white matter of the cerebellar hemispheres. Understanding the anatomy of the white matter and the temporal evolution of this degeneration is essential in identifying WD.

Spontaneous low cerebrospinal pressure: a mini review

Spontaneous intracranial hypotension (SIH) is a syndrome of low cerebrospinal fluid (CSF) pressure characterised by postural headaches in patients without any history of dural puncture or penetrating trauma. Described by Schaltenbrand in 1938, SIH is thought to result from an occult CSF leak resulting in decreased CSF volume and, consequently, in low CSF pressure. Magnetic resonance imaging of the head and spine has improved the diagnosis of the syndrome showing peculiar radiographic abnormalities including diffuse pachymeningeal enhancement, subdural fluid collections and downward displacement of the cerebral structures. Treatment of SIH headache should start with conservative, non-invasive therapies while epidural blood patch has emerged as the treatment of choice for those symptomatic patients who have failed medical noninvasive approaches.

Hyperhomocysteinemia and other thrombophilic risk factors in 26 patients with cerebral venous thrombosis

Despite the continuous description of new conditions pre-disposing for cerebral venous thrombosis (CVT), no apparent cause is found in about 30% of cases. Hyperhomocysteinemia (hyper-Hcy) is an established risk factor for deep venous thrombosis and stroke but has not been clearly associated with increased risk of CVT. We assessed the prevalence of hyper-Hcy and other thrombophilic risk factors in a population of 26 consecutive patients with non-pyogenic CVT, by review of a prospectively maintained database. The prevalences of hyper-Hcy and prothrombin G20210A, factor V G1691A and methylenetetrahydrofolate reductase (MTHFR) C677T mutations in these patients were compared with those in 100 healthy controls and 100 patients with cerebroarterial disease. The prevalence of hyper-Hcy was greater in patients with CVT (10/26, 38.5%) than healthy controls (13/100; OR 4.18, 95% CI 1.58-11.16) and comparable with that in patients with cerebroarterial disease (42/100). No significant differences were found in the prevalences of prothrombin or MTHFR mutation. No factor V mutation was found. Our findings indicate that hyper-Hcy is associated with an increased risk of CVT. Additional prospective cohort studies on large series of patients are required to clarify the time relationship between hyper-Hcy and the thrombotic event.

Cerebral vein thrombosis and mild hyperhomocysteinemia: three new cases

Mild hyperhomocysteinemia is an established risk factor for deep vein thrombosis. We report three patients with cerebral vein thrombosis (CVT) in which the only risk factor we were able to identify was increased blood homocysteine levels and the C677T polymorphism in both alleles of the methylene tetrahydrofolate reductase MTHFR gene. We suggest that hyperhomocysteinemia should also be a risk factor for CVT. Since this condition can be effectively and safely corrected by drugs, we suggest that homocysteine levels should be routinely determined in patients with idiopatic CVT, and even mildly increased levels corrected pharmacologically, in the hope of reducing the risks associated with this condition.

Defective fibrinolytic response in atherosclerotic patients--effect of iloprost and its possible mechanism of action

Plasma fibrinolytic activity and tissue-type plasminogen activator (t-PA) were defective in response to venous stasis in five out of ten patients with peripheral occlusive artery disease. Discontinuous infusions of iloprost, a stable synthetic analogue of prostacyclin, restored a normal fibrinolytic response in all five patients but did not induce a parallel increase of plasma t-PA. These findings suggest that in addition to the possible benefits due to its vasodilatory and antiplatelet activity, iloprost may improve the fibrinolytic activity in patients with atherosclerotic disease, providing them with further antithrombotic protection. The profibrinolytic effect of iloprost seems not to depend on its ability to induce vascular t-PA release. Rather, it might be related to its inhibitory effect on PAI release from platelets, endothelial cells and/or hepatocytes. Venous occlusion test represents an easy diagnostic approach to fibrinolytic defects, even if related to arterial disease, and may help select patients who need therapeutic intervention.

Resumption of gainful employment in aphasics: preliminary findings

We report preliminary data on aphasic patients who, in spite of their language problems, have succeeded in finding a reasonably satisfactory occupational resettlement. Patients who: (a) still had a moderate to sever aphasia, (b) had resumed a gainful employment requiring interpersonal communication, were recalled for a check-up and assessed with: (1) a comprehensive aphasia test: (2) a semistructured interview including detailed questioning about the type and reaction to aphasia, the type of work before the onset of aphasia, the type of current work with particular emphasis on the patients' compensatory mechanisms and emotional reactions. Results comprise 10 cases up to date. One case is described in detail. Findings indicate that the ability to resume a gainful occupation is often greater than could be expected on the sole basis of formal language examination. Findings are discussed from a neuropsychological, social and rehabilitation point of view.

Low dose aspirin does not prevent fibrinolytic response to venous occlusion

Interest in the antithrombotic potential of low-dose aspirin is based on its ability to inhibit thromboxane (Tx)A2-related platelet function with concomitant sparing of vascular prostacyclin (PGI2) production. The aim of this study was to investigate the effect of low-dose aspirin (20 mg daily for 7 days) on the increase in fibrinolytic activity in healthy volunteers after venous occlusion. We also tested the effect of high-dose aspirin (650 mg X 2), of salicylate (569 mg X 2) and of indobufen (200 mg X 2), a new cyclo-oxygenase inhibitor unrelated to salicylates. Low-dose aspirin reduced serum TxB2 generation by about 90% and suppressed arachidonate-induced platelet aggregation. In contrast, fibrinolytic activity, measured by the euglobulin lysis area and the euglobulin lysis time, was not significantly affected. Both high-dose aspirin and indobufen significantly inhibited TxB2 generation and the rise in fibrinolytic activity induced by venous occlusion, without affecting the pre-occlusion values. Salicylate did not significantly affect any parameter studied. Besides offering a favorable solution to the "aspirin dilemma" related to the TxA2/PGI2 balance, low-dose aspirin might leave intact the fibrinolytic capacity of the vessel wall.