Alterations of inflammatory cytokines in super-acute stroke patients and the potential pathogenesis

The Role of Systemic Inflammation in the Pathogenesis of Spontaneous Intracranial Hemorrhage in the Presence or Absence of Effective Cerebral Blood Flow

Background: Spontaneous intracerebral hemorrhage (ICH) is one of the leading causes of mortality in intensive care units. The role of systemic hyperintense inflammation (SHI) in the pathogenesis of critical complications of ICH remains a poorly understood problem. There is a specific variant of severe ICH associated with increased intracranial pressure and occlusion of intracranial vessels, defined as ineffective cerebral blood flow (IECBF). Methods: To evaluate the role of SHI in the pathogenesis of severe (comatose) ICH in a dynamic comparison of patients with IECBF (n-26) and without IECBF (n-52). The SHI integral score criterion (SI scale) was used, including certain values of plasma concentrations of IL-6, IL-8, IL-10; TNF-α, PCT, cortisol, myoglobin, troponin I, D-dimer, and, additionally, SOFA scale values. Blood levels of ACTH and neuron-specific enolase (NSE) were also assessed. Results: Twenty-eight-day mortality in severe ICH reached 84.6% (without IECBF) and 96.2% (with IECBF). Clear signs of SHI were detected in 61.5%/87.8% (without IECBF) and 0.0%/8.7% (with IECBF) within 1-3/5-8 days from the onset of ICH manifestation. The lower probability of developing SHI in the IECBF group was associated with low blood NSE concentrations. Conclusions: The development of SHI in ICH is pathogenetically related to the permeability of the blood-brain barrier for tissue breakdown products and other neuroinflammatory factors.

Peripheral inflammatory response in people after acute ischaemic stroke and isolated spontaneous cervical artery dissection

The systemic inflammatory response following acute ischaemic stroke remains incompletely understood. We characterised the circulating inflammatory profile in 173 acute ischaemic stroke patients by measuring 65 cytokines and chemokines in plasma. Participants were grouped based on their inflammatory response, determined by high-sensitivity C-reactive protein levels in the acute phase. We compared stroke patients' profiles with 42 people experiencing spontaneous cervical artery dissection without stroke. Furthermore, variations in cytokine levels among stroke aetiologies were analysed. Follow-up samples were collected in a subgroup of ischaemic stroke patients at three and twelve months. Ischaemic stroke patients had elevated plasma levels of HGF and SDF-1α, and lower IL-4 levels, compared to spontaneous cervical artery dissection patients without stroke. Aetiology-subgroup analysis revealed reduced levels of nine cytokines/chemokines (HGF, SDF-1α, IL-2R, CD30, TNF-RII, IL-16, MIF, APRIL, SCF), and elevated levels of IL-4 and MIP-1β, in spontaneous cervical artery dissection (with or without ischaemic stroke as levels were comparable between both groups) compared to other aetiologies. The majority of cytokine/chemokine levels remained stable across the study period. Our research indicates that stroke due to large artery atherosclerosis, cardioembolism, and small vessel occlusion triggers a stronger inflammatory response than spontaneous cervical artery dissection.

Longitudinal change of six common inflammatory cytokines and their relationship to anxiety, depression, and cognitive impairment in acute ischemic stroke patients

Inflammatory cytokines are known to be involved in acute ischemic stroke (AIS), while the relationship of multiple inflammatory cytokines with mental disorders in AIS is less reported. This research intended to explore the longitudinal variation of common inflammatory cytokines and their correlation with anxiety, depression, and cognitive impairment in AIS patients. Six inflammatory cytokines were detected by enzyme-linked immunosorbent assay among 175 AIS patients at admission (baseline) and on the day (D)1, D3, and D7 after admission. Anxiety, depression, and cognition were evaluated using the Hospital Anxiety and Depression Scale and Mini-Mental State Examination at discharge, respectively. Anxiety, depression, and cognitive impairment rates were 32.6, 39.4, and 19.4%, respectively. Tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-8, and IL-17A increased from baseline to D1, then decreased from D1 to D7 (all P<0.001), while IL-10 presented an opposite trend (P<0.001). Interestingly, TNF-α on D1 and D3, IL-6 on D3, IL-8 on D3 and D7, and IL-17A on D1, D3, and D7 correlated with higher anxiety rate (all P<0.05). TNF-α on D1, D3, and D7, IL-8 at baseline, D1, D3, and D7, IL-17A on D1 and D7 correlated with increased depression rate (all P<0.05). In addition, IL-1β on D1 and IL-17 at baseline, D1, D3, and D7 correlated with elevated cognitive-impairment rate (all P<0.05). Inflammatory cytokines were dysregulated after disease onset, and their longitudinal change correlated with psychological issues in AIS patients.

Plasma protein alterations during human large vessel stroke: A controlled comparison study

BACKGROUND

Stroke is a major cause of death and disability in the United States. Mechanical thrombectomy (MT) ¹ and tissue plasminogen activator are the current treatments for ischemic stroke, which have improved clinical outcomes. Despite these treatments, functional and cognitive deficits still occur demonstrating a need for predictive biomarkers for beneficial clinical outcomes which can be used as therapeutic targets for pharmacotherapy. The aim of this study compares the proteomic expression of systemic arterial blood collected at the time of MT to those from a matched cerebrovascular disease (CVD) control cohort.

METHODS

The Blood and Clot Thrombectomy Registry and Collaboration (BACTRAC) (clinicaltrials.gov NCT03153683) collects and banks arterial blood, both distal and proximal to the thrombus, from ischemic stroke subjects undergoing MT. Arterial blood from patients undergoing a diagnostic angiogram was also collected and banked as CVD controls. Changes in cardiometabolic and inflammatory proteins between stroke and CVD controls were analyzed via Olink Proteomics.

RESULTS

Proteins including ARTN, TWEAK, HGF, CCL28, FGF-5, CXCL9, TRANCE and GDNF were found to be decreased in stroke subjects when compared to CVD controls. CXCL1, CCL5, OSM, GP1BA, IL6, MMP-1, and CXCL5 were increased in stroke subjects when compared to CVD controls. These proteins were also significantly correlated to stroke outcome metrics such as NIHSS, infarct volume and MoCA scoring.

CONCLUSION

Overall, acute stroke patients had an increase in inflammatory proteins with a decrease in trophic proteins systemically compared to matched CVD controls. Using our CVD controls, proteins of interest were directly compared to stroke patients with the same cerebrovascular risk factors instead of statistically controlling for comorbidities. The novel methodology of matching an arterial blood CVD control group to a stroke group, as well as controlling for age and comorbid status add to the literature on prognostic stroke biomarkers, which are specific targets for future therapeutics.

Association of Dietary Inflammatory Potential with Blood Inflammation: The Prospective Markers on Mild Cognitive Impairment

Inflammation is known as an important mechanism of cognitive dysfunction. Systemic immune inflammation index (SII) and system inflammation response index (SIRI) are two blood inflammatory markers, which are related to many chronic diseases including cognitive impairment. It is recognized that dietary inflammatory index (DII), which is used to estimate the overall inflammatory potential of diet, may be related to mild cognitive impairment (MCI) as well. This study aimed to explore the relationship between SII, SIRI and DII, as well as the role of these inflammatory indexes on MCI in elderly people. A total of 1050 participants from Beijing were included. Neuropsychological tests were used for cognitive evaluation. Energy-adjusted DII scores were calculated based on semi-quantitative food frequency questionnaire. Blood samples were tested for calculating SII and SIRI. Log-binomial regression models were used to estimate the correlation of indexes. After adjusting demographic characteristics, SII and SIRI in MCI individuals were higher than controls (p ≤ 0.001). DII, SII and SIRI had positive relationship with MoCA scores (p < 0.005). DII also correlated with SIRI in MCI (β = 0.11, p = 0.031). Higher DII and SIRI could definitely increase the risk of MCI, as well as DII and SII (p < 0.005). In conclusion, DII was positively correlated with blood inflammation. The elderly with higher level of DII and SIRI, or DII and SII could be considered as people with higher risk of developing MCI.