Racial disparities in post-stroke functional outcomes in young patients with ischemic stroke.

BACKGROUND AND PURPOSE: Recent studies show rising incidence of stroke in the young, for which risk factors are not well characterized. There is evidence of increased risk in certain racial and ethnic groups. We assessed racial differences in risk factors, stroke etiology, and outcomes among young stroke patients. METHODS: Using data from our inpatient registry for ischemic stroke, we reviewed patients aged 18-50 who were admitted 01/2013 to 04/2018. Race/ethnicity were characterized as non-Hispanic White (NHW), non-Hispanic Black (NHB), Hispanic (HIS). For univariate comparisons Chi-square and Kruskal-Wallis tests were performed as appropriate. Multivariable logistic regression was used to assess impact of race on day seven modified Rankin score (mRS). RESULTS: Among 810 patients with race and outcome data who were admitted in the study period, median age was 43, 57.1% were male, and 36.5% NHW, 43.2% NHB, 20.2% HIS. History of hypertension (HTN), type II diabetes (DM II), smoking, heart failure (CHF), prior stroke, and end-stage renal disease varied significantly by race. Compared to NHW, NHB had higher odds of HTN (OR 2.28, 1.65-3.15), CHF (OR 2.17, 1.06-4.46), and DM II 1.92 (1.25-2.94) while HIS had higher odds of DM II (OR 2.52, 1.55-4.10) and lower odds of smoking (OR 0.56, 0.35-0.90). Arrival NIHSS was higher in NHB, but etiology and rates of tpA treatment and thrombectomy did not vary by race. Compared to NHW patients, NHB (OR 0.50 CI (0.31-0.78)) and HIS (OR 0.37 CI (0.21-0.67)) were less likely to have good functional outcome (mRS <2) at day 7 in adjusted analyses. CONCLUSIONS: In this study, there was a higher prevalence of several modifiable risk factors in NHB and HIS young stroke patients and early functional outcome was worse in these groups. Our study suggests a need for targeted prevention efforts for younger populations at highest risk for stroke.

Systematic model of peripheral inflammation after subarachnoid hemorrhage.

OBJECTIVE: To investigate inflammatory processes after aneurysmal subarachnoid hemorrhage (aSAH) with network models. METHODS: This is a retrospective observational study of serum samples from 45 participants with aSAH analyzed at multiple predetermined time points: <24 hours, 24 to 48 hours, 3 to 5 days, and 6 to 8 days after aSAH. Concentrations of cytokines were measured with a 41-plex human immunoassay kit, and the Pearson correlation coefficients between all possible cytokine pairs were computed. Systematic network models were constructed on the basis of correlations between cytokine pairs for all participants and across injury severity. Trends of individual cytokines and correlations between them were examined simultaneously. RESULTS: Network models revealed that systematic inflammatory activity peaks at 24 to 48 hours after the bleed. Individual cytokine levels changed significantly over time, exhibiting increasing, decreasing, and peaking trends. Platelet-derived growth factor (PDGF)-AA, PDGF-AB/BB, soluble CD40 ligand, and tumor necrosis factor-α (TNF-α) increased over time. Colony-stimulating factor (CSF) 3, interleukin (IL)-13, and FMS-like tyrosine kinase 3 ligand decreased over time. IL-6, IL-5, and IL-15 peaked and decreased. Some cytokines with insignificant trends show high correlations with other cytokines and vice versa. Many correlated cytokine clusters, including a platelet-derived factor cluster and an endothelial growth factor cluster, were observed at all times. Participants with higher clinical severity at admission had elevated levels of several proinflammatory and anti-inflammatory cytokines, including IL-6, CCL2, CCL11, CSF3, IL-8, IL-10, CX3CL1, and TNF-α, compared to those with lower clinical severity. CONCLUSIONS: Combining reductionist and systematic techniques may lead to a better understanding of the underlying complexities of the inflammatory reaction after aSAH.

Mesenchymal stromal cell secretomes are modulated by suspension time, delivery vehicle, passage through catheter, and exposure to adjuvants.

BACKGROUND AIMS: Extensive animal data indicate that mesenchymal stromal cells (MSCs) improve outcome in stroke models. Intra-arterial (IA) injection is a promising route of delivery for MSCs. Therapeutic effect of MSCs in stroke is likely based on the broad repertoire of secreted trophic and immunomodulatory cytokines produced by MSCs. We determined the differential effects of exposing MSCs to different types of clinically relevant vehicles, and/or different additives and passage through a catheter relevant to IA injections. METHODS: MSCs derived from human bone marrow were tested in the following vehicles: 5% albumin (ALB), 6% Hextend (HEX) and 40% dextran (DEX). Each solution was tested (i) alone, (ii) with low-dose heparin, (iii) with 10% Omnipaque, or (iv) a combination of heparin and Omnipaque. Cells in vehicles were collected directly or passed through an IA catheter, and MSC viability and cytokine release profiles were assessed. RESULTS: Cell viability remained above 90% under all tested conditions with albumin being the highest at 97%. Viability was slightly reduced after catheter passage or exposure to heparin or Omnipaque. Catheter passage had little effect on MSC cytokine secretion. ALB led to increased release of angiogenic factors such as vascular endothelial growth factor compared with other vehicles, while HEX and DEX led to suppression of pro-inflammatory cytokines such as interleukin-6. However, when these three vehicles were subjected to catheter passage and/or exposure to additives, the cytokine release profile varied depending on the combination of conditions to which MSCs were exposed. DISCUSSION: Exposure of MSCs to certain types of vehicles or additives changes the profile of cytokine secretion. The activation phenotype of MSCs may therefore be affected by the vehicles used for these cells or the exposure to the adjuvants used in their administration.

Cryopreservation of Bone Marrow Mononuclear Cells Alters Their Viability and Subpopulation Composition but Not Their Treatment Effects in a Rodent Stroke Model.

The systemic administration of autologous bone marrow (BM) derived mononuclear cells (MNCs) is under investigation as a novel therapeutic modality for the treatment of ischemic stroke. Autologous applications raise the possibility that MNCs could potentially be stored as a banked source. There have been no studies that investigate the effects of cryopreservation of BM-MNCs on their functional abilities in stroke models. In the present study, C57BL/6 mice were subjected to middle cerebral artery occlusion (MCAo) for 60 minutes and then divided into two treatment groups: fresh MNCs versus cryopreserved MNCs. BM-MNCs were collected at 22 hours after MCAo and were stored in liquid nitrogen for 12 months in cryopreserved MNCs group. BM-MNCs cellular viability, composition, and phenotype of the various subpopulations of mice BM-MNCs were evaluated by flow cytometry, and the behavioral recovery of stroke animals was tested with freshly harvested MNCs versus cryopreserved MNCs by corner test and ladder rung test. We found that long-term cryopreservation negatively impacts the cellular viability of bone marrow MNCs. Cryopreservation also alters the cellular composition of various subpopulations within the MNCs. However, despite the changes observed in cryopreserved cells, both fresh and frozen MNCs have similar beneficial effect on behavioral and histological outcomes.

Various Cell Populations Within the Mononuclear Fraction of Bone Marrow Contribute to the Beneficial Effects of Autologous Bone Marrow Cell Therapy in a Rodent Stroke Model.

Cell-based therapies including bone-marrow derived mononuclear cells (MNCs) are now widely being studied because of their pleotropic effects and promising results to improve recovery after stroke in animal models. Unlike other types of cell therapies, MNCs is a mixture of lymphoid, myeloid, erythroid, and stem cell populations. Which cell population(s) accounts for the beneficial effects of MNCs in stroke recovery is unclear. In this paper, we employed a mouse stroke model with middle cerebral artery occlusion (MCAo), and used positively and negatively sorted autologous MNCs by MACs to determine which fractions of the MNCs contribute to their beneficial effects. We evaluated the benefits of neurofunctional recovery produced by individual cell lineages within MNCs in a long-term observation study up to 28 days after stroke. Mortality and modulation of inflammation were also compared among different sub-populations. We further studied the impact of neurotoxicity posed by activated microglia in the presence of different cell lineages within MNCs. We concluded that myeloid cell lineage and stem cell/progenitors appeared to be important components within MNCs that contribute to improved outcomes after stroke.

Autologous Bone Marrow Mononuclear Cells Exert Broad Effects on Short- and Long-Term Biological and Functional Outcomes in Rodents with Intracerebral Hemorrhage.

Autologous bone marrow-derived mononuclear cells (MNCs) are a potential therapy for ischemic stroke. However, the effect of MNCs in intracerebral hemorrhage (ICH) has not been fully studied. In this study, we investigated the effects of autologous MNCs in experimental ICH. ICH was induced by infusion of autologous blood into the left striatum in young and aged male Long Evans rats. Twenty-four hours after ICH, rats were randomized to receive an intravenous administration of autologous MNCs (1 × 10(7) cells/kg) or saline. We examined brain water content, various markers related to the integrity of the neurovascular unit and inflammation, neurological deficit, neuroregeneration, and brain atrophy. We found that MNC-treated young rats showed a reduction in the neurotrophil infiltration, the number of inducible nitric oxide synthase-positive cells, and the expression of inflammatory-related signalings such as the high-mobility group protein box-1, S100 calcium binding protein B, matrix metalloproteinase-9, and aquaporin 4. Ultimately, MNCs reduced brain edema in the perihematomal area compared with saline-treated animals at 3 days after ICH. Moreover, MNCs increased vessel density and migration of doublecortin-positive cells, improved motor functional recovery, spatial learning, and memory impairment, and reduced brain atrophy compared with saline-treated animals at 28 days after ICH. We also found that MNCs reduced brain edema and brain atrophy and improved spatial learning and memory in aged rats after ICH. We conclude that autologous MNCs can be safely harvested and intravenously reinfused in rodent ICH and may improve long-term structural and functional recovery after ICH. The results of this study may be applicable when considering future clinical trials testing MNCs for ICH.

A Meta-Analysis of Mesenchymal Stem Cells in Animal Models of Parkinson's Disease.

Multiple studies have been performed to evaluate the effects of mesenchymal stem cells (MSCs) in animal models of Parkinson's disease (PD). We performed a meta-analysis to estimate the treatment effect of unmodified MSCs on behavioral outcomes in preclinical studies of PD. We performed a systematic literature search to identify studies that used behavioral testing to evaluate the treatment effect of unmodified MSCs in PD models. Meta-analysis was used to determine pooled effect size for rotational behavior and limb function, and meta-regression was performed to explore sources of heterogeneity. Twenty-five studies, including three delivery routes, a wide range of doses, and multiple PD models, were examined. Significant improvement was seen in the pooled standardized mean difference (SMD) for both rotational behavior [SMD: 1.24, 95% confidence interval (95% CI): 0.84, 1.64] and limb function (SMD: 0.84, 95% CI: 0.01, 1.66). Using meta-regression, intravenous administration and higher dose had a larger effect on limb function. Treatment with MSCs improves behavioral outcomes in PD models. Our analyses suggest that MSCs could be considered for early-stage clinical trials in the treatment of PD.

Efficient manufacturing of therapeutic mesenchymal stromal cells with the use of the Quantum Cell Expansion System.

BACKGROUND: The use of bone marrow-derived mesenchymal stromal cells (MSCs) as a cellular therapy for various diseases, such as graft-versus-host disease, diabetes, ischemic cardiomyopathy and Crohn's disease, has produced promising results in early-phase clinical trials. However, for widespread application and use in later phase studies, manufacture of these cells must be cost-effective, safe and reproducible. Current methods of manufacturing in flasks or cell factories are labor-intensive, involve a large number of open procedures and require prolonged culture times. METHODS: We evaluated the Quantum Cell Expansion System for the expansion of large numbers of MSCs from unprocessed bone marrow in a functionally closed system and compared the results with a flask-based method currently in clinical trials. RESULTS: After only two passages, we were able to expand a mean of 6.6 × 10(8) MSCs from 25 mL of bone marrow reproducibly. The mean expansion time was 21 days, and cells obtained were able to differentiate into all three lineages: chondrocytes, osteoblasts and adipocytes. The Quantum was able to generate the target cell number of 2.0 × 10(8) cells in an average of 9 fewer days and in half the number of passages required during flask-based expansion. We estimated that the Quantum would involve 133 open procedures versus 54,400 in flasks when manufacturing for a clinical trial. Quantum-expanded MSCs infused into an ischemic stroke rat model were therapeutically active. CONCLUSIONS: The Quantum is a novel method of generating high numbers of MSCs in less time and at lower passages when compared with flasks. In the Quantum, the risk of contamination is substantially reduced because of the substantial decrease in open procedures.

Intra-arterial delivery is not superior to intravenous delivery of autologous bone marrow mononuclear cells in acute ischemic stroke.

BACKGROUND AND PURPOSE: Bone marrow-derived mononuclear cells (MNCs) are an investigational autologous cell-based therapy for acute ischemic stroke. Both intravenous (IV) and intra-arterial (IA) administration routes have been used in clinical trials. However, the route of administration to optimize the effect of MNCs is unknown. In this study, we compared the effect of IV versus IA route of administration of MNCs in the rat stroke model. METHODS: Long Evans rats were subjected to transient middle cerebral artery occlusion. At 24 hours after stroke, animals were randomly assigned to receive autologous bone marrow-derived MNCs using either the IV or IA delivery route. IV saline served as control. One million cells/kg (low dose) and 30 million cells/kg (high dose) were assessed. Neurological testing, cavity size, serum cytokines, neuroregenerative end points, and MNC biodistribution were evaluated. RESULTS: High-dose MNCs improved functional recovery, reduced lesion size and proinflammatory cytokines, and increased vessel density and neurogenesis markers compared with saline treatment (P<0.05). However, there were no significant differences between IV and IA MNC-treated groups, although IV MNCs reduced serum interleukin-1ß levels compared with IA MNCs (P<0.05). IA MNCs at high dose led to a greater number of cells in the brain at 1 and 6 hours after injection but not in the lungs and spleen. Low-dose MNCs (by IV or IA) did not improve any functional or structural end point compared with saline. CONCLUSIONS: At low and high doses of MNCs, we found that IV or IA achieves similar structural and functional outcomes after stroke.

Urinary catalytic iron in obesity.

INTRODUCTION: Obesity precedes the development of many cardiovascular disease risk factors, including type 2 diabetes mellitus (DM), hypertension, and chronic kidney disease. Catalytic iron, which has been associated with these chronic diseases, may be one of the links between obesity and these multifactorial diverse disorders. OBJECTIVE: We investigated whether urinary catalytic iron is increased in obese individuals without DM and overt kidney disease. STUDY DESIGN: We measured urinary catalytic iron using established methods in 200 randomly selected individuals without DM [100 who were obese (body mass index ≥30 kg/m(2)) and 100 who were nonobese (body mass index ≤27)]. Participants were selected from an outpatient clinic and community setting and were part of an ongoing cross-sectional study of obesity in individuals between the ages of 18 and 70 years. RESULTS: There was a significant difference in mean (95% CI) urinary catalytic iron excretion between the obese participants and the nonobese participants, 463 (343-582) nmol/mg [52.3 (38.8-65.8) nmol/µmol] vs 197 (141-253) nmol/mg [22.3 (15.9-28.6) nmol/µmol]; P < 0.001. The significant predictors of increased urinary catalytic iron were obesity (P = 0.001) and waist-to-hip ratio (P = 0.03). CONCLUSIONS: Our study results demonstrate that obesity and waist-to-hip ratio are associated with increased urinary catalytic iron, which may be a useful marker of oxidative stress. Additional studies are needed to determine the role of catalytic iron in increased cardiovascular disease and chronic kidney disease associated with obesity.