Plasma Retinol-Binding Protein 4 Levels and the Risk of Ischemic Stroke among Women

Impact of vitamins A, D, and homocysteine on cardiometabolic multimorbidity in Northwest China

OBJECTIVE

To investigate the impact of vitamin A (VA), vitamin D (VD), and homocysteine (Hcy) on cardiometabolic multimorbidity (CMM).

METHODS

This study is a cross-sectional study conducted in Ningxia Province, China. A total of 5000 participants aged 25-74 were recruited and divided into two groups based on the definition of cardiometabolic multimorbidity: the CMM group and the Non CMM group. Demographic, lifestyle, and laboratory data were collected to investigate the correlation between vitamin A, D, Hcy levels and CMM risk. The association was analyzed using multiple logistic regression and restricted cubic spline method.

RESULTS

CMM incidence increased with age, being higher in females (20.05%) compared to males, Hypertension was present in 96.20% of CMM cases. Reduced VD levels correlated with an elevated CMM risk (OR = 1.799, 95% CI: 1.466-2.238), showing an inverse dose-response relationship, even after adjusting for confounders (OR = 1.553, 95% CI: 1.233-1.956). However, VA and Hcy levels were not significantly associated with CMM risk. The inverse correlation between VD status and CMM risk was more pronounced in males, obese individuals, and those with normal blood lipid profiles (P < 0.05).

CONCLUSIONS

The risk of CMM increases with age, especially in women. Inadequate VD status increases vulnerability to CMM, suggesting that optimising VD reduces the risk of CMM.

Exploratory Mass Spectrometry of Cerebrospinal Fluid from Persons with Autopsy-Confirmed LATE-NC

Common neuropathologies associated with dementia include Alzheimer's disease neuropathologic change (ADNC) and limbic-predominant age-related TDP-43 encephalopathy neuropathologic change (LATE-NC). Biofluid proteomics provides a window into the pathobiology of dementia and the information from biofluid tests may help guide clinical management. Participants (n = 29) had been autopsied and had antemortem CSF draws in a longitudinal cohort of older adults at the University of Kentucky AD Research Center. Cases were designated as LATE-NC + if they had LATE-NC stage > 1 (n = 9); the remaining 20 cases were designated LATE-NC-. This convenience sample of CSF specimens was analyzed in two separate processes: From one group, aliquots were depleted of highly abundant proteins using affinity spin columns. Tryptic digests of sample proteins were subjected to liquid chromatographic separation and mass spectrometry. Relative quantification was performed using Sciex software. Peptides referent to a total of 949 proteins were identified in the samples depleted of abundant proteins, and 820 different proteins were identified in the non-depleted samples. When the Bonferroni/false-discovery statistical correction was applied to account for having made multiple comparison tests, only 4 proteins showed differential expression (LATE-NC + vs LATE-NC-) in the non-depleted samples (RBP4, MIF, IGHG3, and ITM2B). Post hoc western blots confirmed that RBP4 expression was higher in the LATE-NC + cases at the group level. In summary, an exploratory assessment of proteomes of autopsy-confirmed LATE-NC and non-LATE-NC CSF did not demonstrate a clear-cut proteomic fingerprint that distinguished the two groups. There was, however, an increase in RBP4 protein levels in CSF from LATE-NC cases.

Association of vitamin A and its organic compounds with stroke - a systematic review and meta-analysis

PURPOSE

The main purpose of this systematic review was to evaluate the association between the stroke (risk of stroke and the mortality due to stroke) and vitamin A, its organic compounds and its provitamins.

METHOD

Major databases including PubMed, Scopus, and Web of Science were searched. Studies with human samples were included for risk assessment. The association was assessed using odds ratio (log(OR)) and a random-effect model. I2 statistic, variance (tau2) and prediction interval were used for heterogeneity assessment. The funnel plot was used for publication bias.

RESULTS

Twenty-one studies including 5789 stroke patients were retrieved. Twenty studies had sufficient information for quantitative analyses. The pooled effect showed an inverse association between vitamin A and its organic compound with the risk of stroke (log(OR) = -0.46 95%CI (-0.81;-0.12)) and with the risk of mortality due to stroke (log(OR) = -0.39 95%CI (-0.74;-0.04)). However, according to subgroup analyses, the association was dependent on the compound in a way that retinol and beta-carotene were the most effective compounds. The effects of several confounding factors and the threshold levels for vitamin A and its organic compound on the effectiveness were discussed.

CONCLUSION

Insufficiency of retinol and beta-carotene significantly increased the risk of stroke; however, due to heterogeneity between studies more studies are needed for evaluating clinical significance of this outcome.

Exploratory mass spectrometry of cerebrospinal fluid from persons with autopsy-confirmed LATE-NC

Background

Common neuropathologies associated with dementia include Alzheimer's disease neuropathologic change (ADNC) and limbic-predominant age-related TDP-43 encephalopathy neuropathologic change (LATE-NC). Biofluid proteomics provides a window into the pathobiology of dementia and the information from biofluid tests may help guide clinical management.

Methods

Participants were recruited from a longitudinal cohort of older adults at the University of Kentucky AD Research Center. A convenience sample of clinically obtained lumbar puncture cerebrospinal fluid (CSF) samples was analyzed from 29 older adults that had autopsy confirmation of the presence or absence of LATE-NC. Nine of the participants had autopsy-confirmed LATE-NC. Antemortem CSF specimens were analyzed in two separate processes: From one group, aliquots were depleted of highly abundant proteins using affinity spin columns. Tryptic digests of sample proteins were subjected to liquid chromatographic separation and mass spectrometry using an Eksigent Ekspert nanoLC 400 system in line with a Sciex 6600+ mass spectrometer. Protein identification was performed using Protein Pilot (Sciex, ver. 5) software, and relative quantification was performed using the SWATH processing microApp in PeakView and MarkerView software (Sciex), respectively. Following data analyses, additional studies were performed using western blots.

Results

A total of 830 proteins were identified in the samples depleted of abundant proteins, and 730 proteins were identified in the non-depleted samples. Whereas some dementia-related proteins were detected (Aβ peptide and α-synuclein protein), others were not (TDP-43, TMEM106B, and tau proteins). When the Bonferroni correction was applied to correct for multiple comparisons, only 4 proteins showed differential expression (LATE-NC vs non-LATE-NC) in the nondepleted samples (RBP4, MIF, IGHG3 and ITM2B), whereas none showed statistically different changes in the depleted samples. Post-hoc western blots confirmed that RBP4 expression was higher in the LATE-NC cases at the group level, but there was overlap between the levels of RBP4 in LATE-NC and non-LATE-NC cases.

Conclusions

An exploratory assessment of CSF proteomes of autopsy-confirmed LATE-NC and non-LATE-NC cases from a community-based cohort failed to demonstrate a clear-cut proteomic fingerprint that distinguished the two groups. There was intriguing increase in RBP4 protein levels in CSF from LATE-NC cases. This may provide clues about pathogenetic mechanisms in LATE-NC.

Longitudinal Change of Plasma Retinol-Binding Protein 4 and its Relation to Neurological-Function Recovery, Relapse, and Death in Acute Ischemic Stroke Patients

Retinol-binding protein 4 (RBP4) promotes dyslipidemia, insulin resistance, inflammation, and atherosclerosis, etc. which may participate in the progression of acute ischemia stroke (AIS). This study aimed to evaluate the longitudinal change of RBP4 after disease onset and its correlation with prognosis in AIS patients. Plasma RBP4 was measured by enzyme-linked immunosorbent assays in 402 AIS patients at admission, one day (D1), 3 days (D3), 7 days (D7), and 30 days (D30) after admission; and in 100 healthy controls after enrollment. The neurological-function recovery was evaluated by the modified Rankin Scale (mRS) at 3 months (M3); disease relapse and death were also recorded during a median 20-month follow-up in AIS patients. Our study revealed that RBP4 was elevated in AIS patients compared with healthy controls. RBP4 was related to a history of diabetes mellitus, a history of cardiovascular disease, and elevated National Institutes of Health Stroke Scale score in AIS patients. Longitudinally, RBP4 was increased from admission to D1/D3, then reduced gradually to D30 in AIS patients. Notably, RBP4 at admission and D1 was elevated in AIS patients with mRS > 2 compared to those with mRS ≤ 2. Meanwhile, RBP4 at admission, D1, D3, D7, and D30 were all higher in AIS patients occurred relapse than those without; RBP4 at D3, D7, and D30 were also higher in AIS patients who died later than those who survived. In conclusion, plasma RBP4 originally elevates and continuously decreases during disease, which forecasts neurological-function recovery status, relapse, and death risk of AIS.

Biomarkers for prognostic functional recovery poststroke: A narrative review

Background and objective: Prediction of poststroke recovery can be expressed by prognostic biomarkers that are related to the pathophysiology of stroke at the cellular and molecular level as well as to the brain structural and functional reserve after stroke at the systems neuroscience level. This study aimed to review potential biomarkers that can predict poststroke functional recovery. Methods: A narrative review was conducted to qualitatively summarize the current evidence on biomarkers used to predict poststroke functional recovery. Results: Neurophysiological measurements and neuroimaging of the brain and a wide diversity of molecules had been used as prognostic biomarkers to predict stroke recovery. Neurophysiological studies using resting-state electroencephalography (EEG) revealed an interhemispheric asymmetry, driven by an increase in low-frequency oscillation and a decrease in high-frequency oscillation in the ipsilesional hemisphere relative to the contralesional side, which was indicative of individual recovery potential. The magnitude of somatosensory evoked potentials and event-related desynchronization elicited by movement in task-related EEG was positively associated with the quantity of recovery. Besides, transcranial magnetic stimulation (TMS) studies revealed the potential values of using motor-evoked potentials (MEP) and TMS-evoked EEG potentials from the ipsilesional motor cortex as prognostic biomarkers. Brain structures measured using magnetic resonance imaging (MRI) have been implicated in stroke outcome prediction. Specifically, the damage to the corticospinal tract (CST) and anatomical motor connections disrupted by stroke lesion predicted motor recovery. In addition, a wide variety of molecular, genetic, and epigenetic biomarkers, including hemostasis, inflammation, tissue remodeling, apoptosis, oxidative stress, infection, metabolism, brain-derived, neuroendocrine, and cardiac biomarkers, etc., were associated with poor functional outcomes after stroke. However, challenges such as mixed evidence and analytical concerns such as specificity and sensitivity have to be addressed before including molecular biomarkers in routine clinical practice. Conclusion: Potential biomarkers with prognostic values for the prediction of functional recovery after stroke have been identified; however, a multimodal approach of biomarkers for prognostic prediction has rarely been studied in the literature. Future studies may incorporate a combination of multiple biomarkers from big data and develop algorithms using data mining methods to predict the recovery potential of patients after stroke in a more precise way.

Correlation of serum RBP4 level with oxidative stress and unstable carotid plaque in patients with cerebral infarction

Objectives

This study aimed to investigate the changes in serum levels of retinol-binding protein 4 (RBP4) with cerebral infarction, relationship of RBP4 with oxidative stress and carotid atherosclerosis, and its possible role in cerebral infarction.

Materials and methods

According to the results of cervical vascular ultrasound, the experimental group was divided into three groups: intima thickening group (n = 31), stable plaque group (n = 51), and unstable plaque group (n = 54). Forty healthy subjects were selected as the control group. Their serum levels of RBP4, 8-iso-prostaglandin-F2alpha (8-iso-PGF2α), and catalase (CAT) were measured. Carotid vascular ultrasound was used to measure the plaque area and intima-media thickness (IMT).

Results

The serum RBP4 and 8-iso-PGF2α levels, IMT and plaque area in the control, intimal thickening, stable plaque, and unstable plaque groups increased, while the serum level of CAT decreased (P < 0.001). The serum levels of RBP4 positively correlated with 8-iso-PGF2α, IMT, and plaque area and negatively correlated with CAT level. The area under the receiver operating characteristic curve was 0.778 in predicting unstable plaques.

Conclusions

The serum levels of RBP4 were significantly elevated in elderly patients with cerebral infarction and correlated with oxidative stress injury and the degree of atherosclerosis. Serum RBP4 has diagnostic value for unstable plaques in carotid arteries.

Retinol and Retinol Binding Protein 4 Levels and Cardiometabolic Disease Risk

BACKGROUND

Despite mechanistic studies linking retinol and RBP4 (retinol binding protein 4) to the pathogenesis of cardiovascular diseases (CVD) and type 2 diabetes (T2D), epidemiological evidence is still conflicting. We investigated whether conflicting results of previous studies may be explained by differences in the association of retinol and RBP4 with cardiometabolic risk across subgroups with distinct sex, hypertension state, liver, or kidney function.

METHODS

We used case-cohorts nested in the EPIC (European Prospective Investigation Into Cancer and Nutrition)-Potsdam cohort (N=27 548) comprising a random sample of participants (n=2500) and all physician-verified cases of incident CVD (n=508, median follow-up time 8.2 years) and T2D (n=820, median follow-up time 6.3 years). We estimated nonlinear and linear multivariable-adjusted associations between the biomarkers and cardiometabolic diseases by restricted cubic splines and Cox regression, respectively, testing potential interactions with hypertension, liver, and kidney function. Additionally, we performed 2-sample Mendelian Randomization analyses in publicly available data.

RESULTS

The association of retinol with cardiometabolic risk was modified by hypertension state (P interaction CVD<0.001; P interaction T2D<0.001). Retinol was associated with lower cardiometabolic risk in participants with treated hypertension (hazard ratio_{per SD} [95% CI]: CVD, 0.71 [0.56-0.90]; T2D, 0.81 [0.70-0.94]) but with higher cardiometabolic risk in normotensive participants (CVD, 1.32 [1.06-1.64]; T2D, 1.15 [0.98-1.36]). Our analyses also indicated a significant interaction between RBP4 and hypertension on CVD risk (P interaction=0.04). Regarding T2D risk, we observed a u-shaped association with RBP4 in women (P nonlinearity=0.01, P effect=0.02) and no statistically significant association in men. The biomarkers' interactions with liver or kidney function were not statistically significant. Hypertension state-specific associations for retinol concentrations with cardiovascular mortality risk were replicated in National Health and Nutrition Examination Survey III.

CONCLUSIONS

Our findings suggest a hypertension-dependent relationship between plasma retinol and cardiometabolic risk and complex interactions of RBP4 with sex and hypertension on cardiometabolic risk.

The association between retinol-binding protein 4 and prediabetes in obese patients with nonalcoholic fatty liver disease

CONTEXT

Retinol-binding protein 4 (RBP4) is associated with visceral fat and insulin resistance (IR) in obesity, type 2 diabetes mellitus (T2DM) and nonalcoholic fatty liver disease (NAFLD), but some of these data remain controversial.

OBJECTIVE

This study evaluated the relationship between serum RBP4 levels and prediabetes in obese patients with NAFLD.

METHODS

A total of 79 obese NAFLD patients without (n = 41) and with prediabetes (n = 38) were included. Serum RBP4 was measured using ELISA method.

RESULTS

Higher RBP4 serum levels were observed in patients with prediabetes, metabolic syndrome (MetS), or dyslipidaemia. There was correlation between RBP4 levels and visceral adiposity index (VAI), glucose, insulin, HOMA-IR, and Quicki index. RBP4 ≥ 61 mcg/ml have about 3.5-fold higher risk of prediabetes (OR 3.544, 95% CI 1.385-9.072, p=.008), and RBP4 ≥ 55 mcg/ml increased the risk for MetS approximately 3.1 times.

CONCLUSIONS

RBP4 is associated with increased risk for prediabetes and MetS in obese patients with NAFLD.

The Effects of RBP4 and Vitamin D on the Proliferation and Migration of Vascular Smooth Muscle Cells via the JAK2/STAT3 Signaling Pathway

Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) are one of the main causes of the development of diabetic atherosclerotic process. The aim of our study was to assess the role of RBP4 in the proliferation and migration of VSMCs and the inhibitory effect of vitamin D on the mechanisms. In an in vivo experiment, rats were randomly classified into 6 groups: the control group, diabetic rats, diabetic atherosclerotic rats (diabetic rats intraperitoneally injected with RBP4), diabetic atherosclerotic rats treated with 0.075 μg kg⁻¹ d⁻¹ vitamin D, 0.15 μg kg⁻¹ d⁻¹ vitamin D and 0.3 μg kg⁻¹ d⁻¹ vitamin D. We found that the levels of JAK2, STAT3, cylinD1, and Bcl-2 were increased in diabetic atherosclerotic rats, and these increases were improved after vitamin D supplementation. Furthermore, to investigate the underlying molecular mechanisms, cells were cultured with glucose in the presence of RBP4 and the absence of RBP4, respectively, and vitamin D of different concentrations and different intervention times was simultaneously adopted. The proliferation and migration of VSMCs was enhanced and the levels of JAK2, STAT3, cyclinD1, and Bcl-2 were increased in the cells transfected with RBP4 overexpression plasmid. Moreover, vitamin D supplementation was detected to lower the expressions of JAK2, STAT3, cyclinD1, and Bcl-2 and inhibit the abnormal proliferation of VSMCs caused by the RBP4/JAK2/STAT3 signaling pathway. RBP4 can promote the proliferation and migration of VSMCs and contributes to the development of diabetic macroangiopathy via regulating the JAK2/STAT3 signaling pathway. This mechanism of RBP4 can be inhibited by vitamin D supplementation.

The prognostic role of RBP-4 and adiponectin in patients with peripheral arterial disease undergoing lower limb endovascular revascularization

BACKGROUND

RBP4 is an adipokine with an established role in atherosclerosis, while adiponectin has unique anti-inflammatory properties. We investigated the association of RBP4 and adiponectin with the presence of symptomatic peripheral artery disease (PAD) and their possible prognostic role in major adverse cardiovascular events (MACE).

METHODS

We enrolled 168 consecutive patients with symptomatic, established PAD, requiring revascularization by endovascular means of any or both of their lower limbs. 88 age- and sex-matched subjects with less than 2 classical cardiovascular risk factors served as controls. Clinical parameters, glycemic and lipid profile, RBP4 and adiponectin levels were assayed. The occurrence of MACE was recorded during the 6-month follow-up and patients were assigned to MACE and non-MACE subgroups.

RESULTS

The presence of symptomatic PAD was significantly correlated with age, diabetes, hsCRP, RBP4 and low adiponectin levels (p < 0.05). After adjustment for age, RBP4 (β = 0.498, p < 0.001), and adiponectin (β = -0.288, p < 0.001) levels remained as independent predictors of PAD presence in the whole study cohort. At baseline, MACE subgroup appeared with higher RBP-4 and hsCRP serum levels than non-MACE subgroup (p < 0.001), but no differences were detected for adiponectin (p = 0.758). Serum RBP4 levels remained independent predictor of MACE (β = 0.455, p < 0.001) after adjustment for traditional cardiovascular risk factors.

CONCLUSIONS

High RBP4 and low adiponectin serum levels are independently associated with PAD presence. In addition, RBP4 is an independent predictor of MACE incidence in symptomatic PAD patients.

Retinol-binding protein 4 in obesity and metabolic dysfunctions

Excessive increased adipose tissue mass in obesity is associated with numerous co-morbid disorders including increased risk of type 2 diabetes, fatty liver disease, hypertension, dyslipidemia, cardiovascular diseases, dementia, airway disease and some cancers. The causal mechanisms explaining these associations are not fully understood. Adipose tissue is an active endocrine organ that secretes many adipokines, cytokines and releases metabolites. These biomolecules referred to as adipocytokines play a significant role in the regulation of whole-body energy homeostasis and metabolism by influencing and altering target tissues function. Understanding the mechanisms of adipocytokine actions represents a hot topic in obesity research. Among several secreted bioactive signalling molecules from adipose tissue and liver, retinol-binding protein 4 (RBP4) has been associated with systemic insulin resistance, dyslipidemia, type 2 diabetes and other metabolic diseases. Here, we aim to review and discuss the current knowledge on RBP4 with a focus on its role in the pathogenesis of obesity comorbid diseases.

Retinol, Retinoic Acid, and Retinol-Binding Protein 4 are Differentially Associated with Cardiovascular Disease, Type 2 Diabetes, and Obesity: An Overview of Human Studies

Vitamin A is a fat-soluble essential nutrient obtained from plant- and animal-based sources that has roles in growth, vision, and metabolism. Vitamin A circulates mainly as retinol bound to retinol-binding protein 4 (RBP4), and is delivered to tissues and converted to retinoic acid, which is a ligand for several nuclear receptors. In recent years, aspects of vitamin A metabolism have been under scrutiny with regards to the development of metabolic and lifestyle diseases including cardiovascular disease (CVD), type 2 diabetes mellitus (T2DM), and overweight and obesity in humans. Studies have mainly focused on RBP4 in this context, whereas the major circulating form, retinol, and the major bioactive form, retinoic acid, have been overlooked in this regard until recently. As one of the main roles of RBP4 is to deliver retinol to tissues for biological action, the associations of retinol and retinoic acid with these diseases must also be considered. In this review, we summarize and discuss recent and available evidence from human studies with focus on retinol, retinoic acid, and RBP4 and provide an overview of these crucial components of vitamin A metabolism in CVD, T2DM, and obesity. In summary, retinol was found to be both inversely and positively associated with CVD whereas the associations with T2DM and obesity were less clear. Although only a few studies have been published on retinoic acid, it was inversely associated with CVD. In contrast, serum RBP4 was mostly found to be positively associated with CVD, T2DM, and obesity. At present, it is difficult to ascertain why the reported associations differ depending on the compound under study, but there is a clear imbalance in the literature in disfavor of retinol and retinoic acid, which needs to be considered in future human studies.

Plasma Levels of Retinol Binding Protein 4 Relate to Large VLDL and Small LDL Particles in Subjects with and without Type 2 Diabetes

Background: Retinol binding protein 4 (RBP4) carries retinol in plasma, but is also considered an adipokine, as it is implicated in insulin resistance in mice. Plasma RBP4 correlates with total cholesterol, low density lipoprotein (LDL)-cholesterol and triglycerides, and may confer increased cardiovascular risk. However, controversy exists about circulating RPB4 levels in type 2 diabetes mellitus (T2DM) and obesity. Here, we analyzed the relationships of RBP4 and retinol with lipoprotein subfractions in subjects with and without T2DM. Methods: Fasting plasma RBP4 (enzyme-linked immunosorbent assay) and retinol (high performance liquid chromatography) were assayed in 41 T2DM subjects and 37 non-diabetic subjects. Lipoprotein subfractions (NMR spectroscopy) were measured in 36 T2DM subjects and 27 non-diabetic subjects. Physical interaction of RBP4 with lipoproteins was assessed by fast protein liquid chromatography (FPLC). Results: Plasma RBP4 and retinol were strongly correlated (r = 0.881, p < 0.001). RBP4, retinol and the RBP4/retinol ratio were not different between T2DM and non-diabetic subjects (all p > 0.12), and were unrelated to body mass index. Notably, RBP4 and retinol were elevated in subjects with metabolic syndrome (p < 0.05), which was attributable to an association with elevated triglycerides (p = 0.013). Large VLDL, total LDL and small LDL were increased in T2DM subjects (p = 0.035 to 0.003). Taking all subjects together, RBP4 correlated with total cholesterol, non-HDL cholesterol, LDL cholesterol, triglycerides and apolipoprotein B in univariate analysis (p < 0.001 for each). Age-, sex- and diabetes status-adjusted multivariable linear regression analysis revealed that RBP4 was independently associated with large VLDL (β = 0.444, p = 0.005) and small LDL particles (β = 0.539, p < 0.001). Its relationship with large VLDL remained after further adjustment for retinol. RBP4 did not co-elute with VLDL nor LDL particles in FPLC analyses. Conclusions: Plasma RBP4 levels are related to but do not physically interact with large VLDL and small LDL particles. Elevated RBP4 may contribute to a proatherogenic plasma lipoprotein profile.

Endovascular Metal Devices for the Treatment of Cerebrovascular Diseases

Cerebrovascular disease involves various medical disorders that obstruct brain blood vessels or deteriorate cerebral circulation, resulting in ischemic or hemorrhagic stroke. Nowadays, platinum coils with or without biological modification have become routine embolization devices to reduce the risk of cerebral aneurysm bleeding. Additionally, many intracranial stents, flow diverters, and stent retrievers have been invented with uniquely designed structures. To accelerate the translation of these devices into clinical usage, an in-depth understanding of the mechanical and material performance of these metal-based devices is critical. However, considering the more distal location and tortuous anatomic characteristics of cerebral arteries, present devices still risk failing to arrive at target lesions. Consequently, more flexible endovascular devices and novel designs are under urgent demand to overcome the deficiencies of existing devices. Herein, the pros and cons of the current structural designs are discussed when these devices are applied to the treatment of diseases ranging broadly from hemorrhages to ischemic strokes, in order to encourage further development of such kind of devices and investigation of their use in the clinic. Moreover, novel biodegradable materials and drug elution techniques, and the design, safety, and efficacy of personalized devices for further clinical applications in cerebral vasculature are discussed.

Evaluation of serum retinol-binding protein-4 levels as a biomarker of poor short-term prognosis in ischemic stroke

The aim was to investigate the relationship between retinol-binding protein 4 (RBP4) levels and short-term functional outcome, and to determine its possible role in acute ischemic stroke (AIS). In a prospective observational study, 299 first-ever AIS who were admitted to our hospital were included. Serum levels of RBP4 were assayed and severity of stroke was evaluated with the National Institutes of Health Stroke Scale (NIHSS) score on admission. The prognostic value of RBP4 to predict the poor outcome within 3 months was compared with the NIHSS and with other known outcome predictors. The median age of the included patients was 66 (interquartile range (IQR): 55-77) years and 155 (51.8%) were women. A poor functional outcome was found in 88 patients (29.4%), and significantly higher RBP4 values were found in poor outcomes rather than good outcomes patients (P<0.001). The poor outcomes distribution across the RBP4 quartiles ranged between 9.3% (first quartile) and 60.8% (fourth quartile). In multivariate models comparing the second(Q2), third, and fourth quartiles against the first quartile of the RBP4, RBP4 in Q3 and Q4 were associated with poor functional outcome, and increased risk of poor functional outcome by 144% (OR: 2.44; 95% confidence interval (CI): 1.22-5.03) and 602% (7.02; 3.11-12.24), respectively. Interestingly, RBP4 improved the NIHSS score (area under the curve (AUC) of the combined model, 0.79; 95% CI: 0.74-0.85; P<0.001). The data showed that elevated serum levels of RBP4 at admission were associated with severity and prognosis of AIS, suggesting that vitamin A metabolism or impaired insulin signaling could be involved.

Retinol-Binding Protein 4 Predicts Lesion Volume (Determined by MRI) and Severity of Acute Ischemic Stroke

Retinol-binding protein 4 (RBP4) is an adipocyte-secreted molecule and is associated with cardiovascular risk factors. The aim of this study was to assess the clinical significance of serum levels of RBP4 in Chinese patients with acute ischemic stroke (AIS). We sequentially screened patients with first-ever AIS who were admitted to our Hospital between September 2016 and October 2017. Serum levels of RBP4 were assayed with solid-phase sandwich ELISA, and severity of stroke was evaluated with the National Institutes of Health Stroke Scale (NIHSS) score on admission. We used logistic regression models to assess the relationship between RBP4 levels and stroke risk and severity. During the inclusion period, 323 patients completed the study. Our results indicated that the median serum RBP4 levels were significantly (P < 0.001) higher in patients with AIS than in those normal cases [28.9 (IQR, 17.3-39.6) μg/ml vs. 23.7 (14.6-32.3) μg/ml]. In logistic regression analysis, for each 1 unit increase of serum level of RBP4, the unadjusted and adjusted risks of AIS increased by 4% (OR 1.04 [95% CI 1.02-1.05], P < 0.001) and 3% (1.03 [1.01-1.04], P < 0.001), respectively. At admission, 116 patients (35.9%) had a minor stroke (NIHSS < 6). In logistic regression analysis, for each 1 unit increase of serum level of RBP4, the unadjusted and adjusted risks of moderate-to-high stroke increased by 7% (OR 1.07 [95% CI 1.05-1.09], P < 0.001) and 5% (1.05 [1.02-1.07], P < 0.001), respectively. Elevated levels of RBP4 could be considered an independent diagnosis marker of AIS. Elevated levels of RBP4 were significantly associated with higher stroke severity in Chinese sample.