Serum caspase-cleaved cytokeratin-18 levels and outcomes after aneurysmal subarachnoid hemorrhage

Biomarkers in aneurysmal subarachnoid hemorrhage: A short review

Poor outcomes of aneurysmal subarachnoid hemorrhage (aSAH) can be the result of the initial catastrophic event or the many acute or delayed neurological complications. Recent evidence suggests that some molecules play a critical role in both events, through some unknown pathways involved. Understanding the role of these molecules in these events could allow to improve diagnostic accuracy, guide management, and prevent long-term disability in aSAH. Here we present the studies on aSAH biomarkers present in current medical literature, highlighting their roles and main results.

Biological Effects and Mechanisms of Caspases in Early Brain Injury after Subarachnoid Hemorrhage

Caspases are an evolutionarily conserved family of proteases responsible for mediating and initiating cell death signals. In the past, the dysregulated activation of caspases was reported to play diverse but equally essential roles in neurodegenerative diseases, such as brain injury and neuroinflammatory diseases. A subarachnoid hemorrhage (SAH) is a traumatic event that is either immediately lethal or induces a high risk of stroke and neurological deficits. Currently, the prognosis of SAH after treatment is not ideal. Early brain injury (EBI) is considered one of the main factors contributing to the poor prognosis of SAH. The mechanisms of EBI are complex and associated with oxidative stress, neuroinflammation, blood-brain barrier disruption, and cell death. Based on mounting evidence, caspases are involved in neuronal apoptosis or death, endothelial cell apoptosis, and increased inflammatory cytokine-induced by apoptosis, pyroptosis, and necroptosis in the initial stages after SAH. Caspases can simultaneously mediate multiple death modes and regulate each other. Caspase inhibitors (including XIAP, VX-765, and Z-VAD-FMK) play an essential role in ameliorating EBI after SAH. In this review, we explore the related pathways mediated by caspases and their reciprocal regulation patterns after SAH. Furthermore, we focus on the extensive crosstalk of caspases as a potential area of research on therapeutic strategies for treating EBI after SAH.

Non-Survivor Ischemic Stroke Patients Maintain High Serum Caspase-Cleaved Cytokeratin-18 Levels

OBJECTIVE

Caspase-cleaved cytokeratin (CCCK)-18 could appear in blood during apoptosis. In two different studies, on day 1 of cerebral infarction and at 72 hours of cerebral infarction, respectively, higher circulating CCCK-18 levels were found in non-surviving than in surviving patients. The objective of this study was to analyze the ability of these levels to predict mortality at any time during the first week of cerebral infarction.

METHODS

Patients with malignant middle cerebral artery infarction (MMCAI) were included and the diagnosis criteria were the presence, observed in a computed tomography, of an acute cerebral infarction in at least 50% of this territory and midline shift, and an acute neurological deterioration with a Glasgow Coma Scale ≤ 8. Serum CCCK-18 levels at days 1, 4 and 8 of MMCAI were determined.

RESULTS

Serum concentrations of CCCK-18 at days 1, 4 and 8 of MMCAI were higher in non-surviving (n = 34) than in surviving patients (n = 34). Serum CCCK-18 concentrations at days 1, 4 and 8 of MMCAI had an area under curve (95% CI) used to predict a 30-day mortality of 0.83 (0.72--0.91; p < 0.001), 0.78 (0.65-0.89; p < 0.001) and 0.82 (0.68-0.92; p < 0.001).

CONCLUSIONS

The novel finding is that serum levels of CCCK-18 levels at any time after the first week of MMCAI could help predict 30-day mortality.

High Serum Caspase-Cleaved Cytokeratin-18 Levels and Mortality of Traumatic Brain Injury Patients

Objective: Apoptosis increases in traumatic brain injury (TBI). Caspase-cleaved cytokeratin (CCCK)-18 in blood during apoptosis could appear. At the time of admission due to TBI, higher blood CCCK-18 levels were found in non-surviving than in surviving patients. Therefore, the objective of our study was to analyze whether serum CCCK-18 levels determined during the first week after TBI could predict early mortality (at 30 days). Methods: Severe TBI patients were included (considering severe when Glasgow Coma Scale < 9) in this observational and multicentre study. Serum CCCK-18 levels were determined at day 1 of TBI, and at days 4 and 8 after TBI. Results: Serum CCCK-18 levels at day 1 of TBI, and in the days 4 and 8 after TBI were higher (p < 0.001) in non-surviving than in surviving patients (34 and 90 patients, respectively) and could predict early mortality (p < 0.001 in the area under the curve). Conclusions: The new findings from our study were that serum CCCK-18 levels at any moment of the first week of TBI were higher in non-surviving patients and were able to predict early mortality.

Subacute Elevation of Plasma Level of Caspase-Cleaved Cytokeratin-18 is Associated with Hemorrhagic Transformation and Functional Outcome in Ischemic Stroke

BACKGROUND

Caspase-cleaved cytokeratin-18 (CCCK-18) is an apoptosis marker. Here, we analyzed the relationship between plasma level of CCCK-18 in the acute and subacute stage of ischemic stroke and early and late functional outcome. Besides, correlation among CCCK-18 and complications, such as hemorrhagic transformation (HT) were also explored.

METHODS

Plasma concentration of CCCK-18 was investigated in 54 patients at admission and poststroke 72 hours. HT was evaluated by CT scans on 24 poststroke hours. Outcome measures were assessed by modified Rankin scale at hospital discharge and 6-month later. Receiver operating characteristics (ROC) analysis was used to determine the best cut-off values of CCCK-18 as a predictor of unfavorable functional outcome.

RESULTS

Significantly elevated CCCK-18 level was observed at 72 hours after onset of stroke, in nonsurviving compared to surviving patients (331 ± 191 ng/L versus 251 ± 164 ng/L, P = .01). Based on ROC analysis, the cut-off value of plasma CCCK-18 levels >223 ng/L at 72 poststroke hours predicted 6-month unfavorable stroke outcome with a sensitivity of 84.4% and a specificity of 77.3% (area under the curve: .851, 95% confidence interval = .745-.955, P < .001). The rate of complications such as HT and in-hospital infection was significantly higher in patients presented with a plasma CCCK-18 level above the cut-off value.

CONCLUSIONS

The association between high serum CCCK-18 levels and unfavorable early and late stroke outcome in an unselected study population was first described here. Besides, the apoptosis marker CCCK-18 might be a predictor of further complication such as HT and in-hospital infection.

Association between serum levels of caspase-cleaved cytokeratin-18 and early mortality in patients with severe spontaneous intracerebral hemorrhage

BACKGROUND

Apoptotic changes after cerebral hemorrhage in brain samples of humans have been found. Caspase-cleaved cytokeratin (CCCK)-18 could be detected in the bloodstream during apoptosis. Higher circulating CCCK-18 levels have been associated with 6-month mortality in patients with basal ganglia hemorrhage. The aim of our study was to determine whether there is an association between serum CCCK-18 levels and early mortality of spontaneous intracerebral hemorrhage (SIH) patients. We performed an observational, prospective and multicentre study. There were included patients with severe SIH defined as Glasgow Coma Scale (GCS) lower than 9. We determined serum CCCK-18 levels at the severe SIH diagnosis moment.

RESULTS

We found that non-surviving SIH patients (n = 46) showed lower GCS, and higher serum CCCK-18 levels and APACHE-II score than survivor ones (n = 54). In ROC analysis was found that the area under the curve of serum CCCK-18 levels for 30-day mortality prediction was 90% (95% CI 82-95%; p < 0.001). In the multiple logistic regression analysis, we found an association between serum CCCK-18 levels and 30-day mortality (OR 1.034; 95% CI 1.013-1.055; p = 0.002).

CONCLUSIONS

The novel finding of our study was that there is an association between high serum CCCK-18 levels and 30-day mortality in severe SIH patients.

High serum levels of caspase-cleaved cytokeratin-18 are associated with malignant middle cerebral artery infarction patient mortality

BACKGROUND

There have been found apoptotic changes in brain tissue samples from humans after cerebral ischemia. Caspase-cleaved cytokeratin (CCCK)-18 could appears in blood during apoptosis. High circulating levels of CCCK-18 have been associated with a poor prognosis in patients with cerebral process, such as traumatic brain injury and spontaneous cerebral hemorrhage. However, they have not been explored in patients with ischemic stroke. Thus, the aim of this study was to determine whether there is an association between serum CCCK-18 levels and mortality in patients with severe malignant middle cerebral artery infarction (MMCAI).

METHODS

This was an observational, prospective and multicentre study. We included patients with severe MMCAI. We considered MMCAI as severe when Glasgow Coma Scale (GCS) was lower than 9. We measured serum CCCK-18 levels at the diagnosis moment of the severe MMCAI.

RESULTS

We found that non-surviving severe MMCAI patients (n = 33) showed lower GCS and platelet count, and higher serum CCCK-18 levels than survivor ones (n = 33). We found an area under the curve (AUC) of serum CCCK-18 levels to predict 30-day mortality of 82% (95% CI = 71%-91%; p < 0.001). In the multiple logistic regression analysis was found that serum CCCK-18 levels were associated with 30-day mortality (OR = 1.023; 95% CI = 1.010-1.037; p = 0.001) after to control for platelet count and GCS.

CONCLUSIONS

To our knowledge, this is the first series reporting data on serum CCCK-18 levels in ischemic stroke patients. The novel findings of our study were that non-surviving severe MMCAI patients had higher serum CCCK-18 levels than surviving patients, and that there is an association between high serum CCCK-18 levels and MMCAI patients mortality.

Prospective clinical biomarkers of caspase-mediated apoptosis associated with neuronal and neurovascular damage following stroke and other severe brain injuries: Implications for chronic neurodegeneration

Acute brain injuries, including ischemic and hemorrhagic stroke, as well as traumatic brain injury (TBI), are major worldwide health concerns with very limited options for effective diagnosis and treatment. Stroke and TBI pose an increased risk for the development of chronic neurodegenerative diseases, notably chronic traumatic encephalopathy, Alzheimer's disease, and Parkinson's disease. The existence of premorbid neurodegenerative diseases can exacerbate the severity and prognosis of acute brain injuries. Apoptosis involving caspase-3 is one of the most common mechanisms involved in the etiopathology of both acute and chronic neurological and neurodegenerative diseases, suggesting a relationship between these disorders. Over the past two decades, several clinical biomarkers of apoptosis have been identified in cerebrospinal fluid and peripheral blood following ischemic stroke, intracerebral and subarachnoid hemorrhage, and TBI. These biomarkers include selected caspases, notably caspase-3 and its specific cleavage products such as caspase-cleaved cytokeratin-18, caspase-cleaved tau, and a caspase-specific 120 kDa αII-spectrin breakdown product. The levels of these biomarkers might be a valuable tool for the identification of pathological pathways such as apoptosis and inflammation involved in injury progression, assessment of injury severity, and prediction of clinical outcomes. This review focuses on clinical studies involving biomarkers of caspase-3-mediated pathways, following stroke and TBI. The review further examines their prospective diagnostic utility, as well as clinical utility for improved personalized treatment of stroke and TBI patients and the development of prophylactic treatment chronic neurodegenerative disease.

Thioredoxin as a marker for severity and prognosis of aneurysmal subarachnoid hemorrhage

OBJECTIVE

Circulating levels of thioredoxin (Trx), a potent anti-oxidant that modulates inflammation, cell growth and apoptosis, are increased in various critical care conditions. The purpose of this study was to establish the relationship between serum Trx levels and prognosis of aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

An enzyme-linked immunosorbent assay measurement of Trx was performed in serum from 132 patients and 132 healthy volunteers. Clinical outcomes included 6-month mortality and unfavorable outcome (Glasgow outcome scale score of 1-3).

RESULTS

The serum Trx levels were significantly higher in patients than in controls (23.4±12.2 ng/mL vs.8.5±4.0 ng/mL, P<0.001) and had close relation to the World Federation of Neurological Surgeons (WFNS) scores (r=0.461, P<0.001) and modified Fisher scores (r=0.459, P<0.001). Trx was an independent predictor for 6-month mortality (Odds ratio, 1.386; 95% confidence interval, 1.015-2.161; P<0.001) and 6-month unfavorable outcome (Odds ratio, 1.297; 95% confidence interval, 1.012-2.002; P<0.001). Based on receiver operating characteristic curve, TRX had similar prognostic value compared with WFNS scores and modified Fisher scores and also significantly improved their prognostic value for 6-month unfavorable outcome, but not for 6-month mortality.

CONCLUSIONS

Elevated plasma Trx levels are correlated with the severity and poor prognosis, substantializing Trx as a potential prognostic predictive biomarker following aSAH.