Increased levels of circulating SDF-1α and CD34+ CXCR4+ cells in patients with moyamoya disease

SDF-1/CXCR4 axis participants in the pathophysiology of adult patients with moyamoya disease

BACKGROUND

Moyamoya disease (MMD) is characterized by an abundance of moyamoya vessels; however, the precise mechanism driving the spontaneous angiogenesis of these compensatory vessels remains unclear. Previous research has established a link between the stromal cell-derived factor-1 (SDF-1)/ CXC receptor 4 (CXCR4) axis and angiogenesis under hypoxic conditions. Nevertheless, the alterations in this axis within the cerebrospinal fluid, arachnoid membranes and vascular tissue of MMD patients have not been fully investigated.

METHODS

Our study enrolled 66 adult MMD patients and 61 patients with atherosclerotic vascular disease (ACVD). We investigated the SDF-1 concentration in cerebrospinal fluid (CSF) and CXCR4 expression level on the arachnoid membranes and vascular tissue. We utilized enzyme-linked immunosorbent assay and immunohistochemistr. Additionally, we cultured and stimulated human brain microvascular endothelial cells (HBMECs) and smooth muscle cells (SMCs) under oxygen and glucose deprivation (OGD) conditions followed by reoxygenation, to examine any changes in the SDF-1/CXCR4 axis.

RESULTS

The results demonstrated an elevation in the level of SDF-1 in CSF among MMD patients compared to those with ACVD. Moreover, the expression of CXCR4 in arachnoid membranes and vascular tissue showed a similar trend. Furthermore, the content of CXCR4 in HBMECs and SMCs increased with the duration of ischemia and hypoxia. However, it was observed that the expression of CXCR4 decreased at OGD/R 24h compared to OGD 24h. The temporal pattern of SDF-1 expression in HBMECs and SMCs mirrored that of CXCR4 expression.

CONCLUSION

These findings indicate a critical role for the SDF-1/CXCR4 axis in the angiogenesis of moyamoya disease.

Molecular Biomarkers Affecting Moyamoya Disease

Although the pathogenetic pathway of moyamoya disease (MMD) remains unknown, studies have indicated that variations in the RING finger protein RNF 213 is the strongest susceptible gene of MMD. In addition to the polymorphism of this gene, many circulating angiogenetic factors such as growth factors, vascular progenitor cells, inflammatory and immune mediators, angiogenesis related cytokines, as well as circulating proteins promoting intimal hyperplasia, excessive collateral formation, smooth muscle migration and atypical migration may also play critical roles in producing this disease. Identification of these circulating molecules biomarkers may be used for the early detection of this disease. In this chapter, how the hypothesized pathophysiology of these factors affect MMD and the interactive modulation between them are summarized.

Physiological and pathophysiological mechanisms of the molecular and cellular biology of angiogenesis and inflammation in moyamoya angiopathy and related vascular diseases

Rationale

The etiology and pathophysiological mechanisms of moyamoya angiopathy (MMA) remain largely unknown. MMA is a progressive, occlusive cerebrovascular disorder characterized by recurrent ischemic and hemorrhagic strokes; with compensatory formation of an abnormal network of perforating blood vessels that creates a collateral circulation; and by aberrant angiogenesis at the base of the brain. Imbalance of angiogenic and vasculogenic mechanisms has been proposed as a potential cause of MMA. Moyamoya vessels suggest that aberrant angiogenic, arteriogenic, and vasculogenic processes may be involved in the pathophysiology of MMA. Circulating endothelial progenitor cells have been hypothesized to contribute to vascular remodeling in MMA. MMA is associated with increased expression of angiogenic factors and proinflammatory molecules. Systemic inflammation may be related to MMA pathogenesis.

Objective

This literature review describes the molecular mechanisms associated with cerebrovascular dysfunction, aberrant angiogenesis, and inflammation in MMA and related cerebrovascular diseases along with treatment strategies and future research perspectives.

Methods and results

References were identified through a systematic computerized search of the medical literature from January 1, 1983, through July 29, 2022, using the PubMed, EMBASE, BIOSIS Previews, CNKI, ISI web of science, and Medline databases and various combinations of the keywords "moyamoya," "angiogenesis," "anastomotic network," "molecular mechanism," "physiology," "pathophysiology," "pathogenesis," "biomarker," "genetics," "signaling pathway," "blood-brain barrier," "endothelial progenitor cells," "endothelial function," "inflammation," "intracranial hemorrhage," and "stroke." Relevant articles and supplemental basic science articles almost exclusively published in English were included. Review of the reference lists of relevant publications for additional sources resulted in 350 publications which met the study inclusion criteria. Detection of growth factors, chemokines, and cytokines in MMA patients suggests the hypothesis of aberrant angiogenesis being involved in MMA pathogenesis. It remains to be ascertained whether these findings are consequences of MMA or are etiological factors of MMA.

Conclusions

MMA is a heterogeneous disorder, comprising various genotypes and phenotypes, with a complex pathophysiology. Additional research may advance our understanding of the pathophysiology involved in aberrant angiogenesis, arterial stenosis, and the formation of moyamoya collaterals and anastomotic networks. Future research will benefit from researching molecular pathophysiologic mechanisms and the correlation of clinical and basic research results.

Increase of Circulating Endothelial Progenitor Cells and Released Angiogenic Factors in Children with Moyamoya Arteriopathy

Moyamoya arteriopathy (MMA) is a rare cerebrovascular disorder that causes recurrent ischemic and hemorrhagic strokes, leading young patients to severe neurological deficits. The pathogenesis of MMA is still unknown. The disease onset in a wide number of pediatric cases raises the question of the role of genetic factors in the disease's pathogenesis. In these patients, MMA's clinical course, or progression, is largely unclear. By performing a comprehensive molecular and cellular profile in the plasma and CSF, respectively, of MMA pediatric patients, our study is aimed at assessing the levels of circulating endothelial progenitor cells (cEPC) and the release of selected proteins at an early disease stage to clarify MMA pathogenesis and progression. We employed cytofluorimetric methods and immunoassays in pediatric MMA patients and matched control subjects by age and sex. We detected increased levels of cEPC in peripheral blood and an upregulation of angiogenic markers in CSF (i.e., angiopoietin-2 and VEGF-A). This finding is probably associated with deregulated angiogenesis, as stated by the moderate severity of collateral vessel network development (Suzuki III-IV). The absence of significant modulation of neurofilament light in CSF led us to rule out the presence of substantial neuronal injury in MMA children. Despite the limited cohort of pediatric patients, we found some peculiar cellular and molecular characteristics in their blood and CSF samples. Our findings may be confirmed by wider and perspective studies to identify predictive or prognostic circulating biomarkers and potential therapeutic targets for personalized care of MMA pediatric patients.

Clinical value of the systemic immune-inflammation index in moyamoya disease

Background

Moyamoya disease (MMD) is a rare cerebrovascular disorder with unknown etiology. The underlying pathophysiological mechanism of moyamoya disease remains to be elucidated, but recent studies have increasingly highlighted that abnormal immune response may be a potential trigger for MMD. Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and systemic immune-inflammation index (SII) are inflammatory markers that can reflect the immune-inflammation state of the disease.

Objective

The purpose of this study was to investigate SII, NLR, and PLR in patients with moyamoya disease.

Methods

A total of 154 patients with moyamoya disease (MMD group) and 321 age- and sex-matched healthy subjects (control group) were included in this retrospective case-control study. Complete blood count parameters were assayed to calculate the SII, NLR, and PLR values.

Results

The SII, NLR, and PLR values in the moyamoya disease group were significantly higher than those in the control group [754 ± 499 vs. 411 ± 205 (P < 0.001), 2.83 ± 1.98 vs. 1.81 ± 0.72 (P < 0.001), and 152 ± 64 vs. 120 ± 42 (P < 0.001), respectively]. The SII in the medium-moyamoya vessels of moyamoya disease was higher than that in the high-moyamoya vessels and low-moyamoya vessels (P = 0.005). Using the receiver operating characteristic (ROC) curve analysis to predict MMD, the highest area under the curve (AUC) was determined for SII (0.76 for SII, 0.69 for NLR, and 0.66 for PLR).

Conclusion

Based on the results of this study, patients with moyamoya disease admitted for inpatient care due to acute or chronic stroke have significantly higher SII, NLR, and PLR when compared to blood samples drawn from completely healthy controls in a non-emergent outpatient setting. While the findings may suggest that inflammation plays a role in moyamoya disease, further studies are warranted to corroborate such an association. In the middle stage of moyamoya disease, there may be a more intense imbalance of immune inflammation. Further studies are needed to determine whether the SII index contributes to the diagnosis or serves as a potential marker of an inflammatory response in patients with moyamoya disease.

Combination of indirect revascularization and endothelial progenitor cell transplantation improved cerebral perfusion and ameliorated tauopathy in a rat model of bilateral ICA ligation

Objective

Endothelial progenitor cells (EPCs) contribute to the recovery of neurological function after ischemic stroke. Indirect revascularization has exhibited promising effects in the treatment of cerebral ischemia related to moyamoya disease and intracranial atherosclerotic disease. The role of EPCs in augmenting the revascularization effect is not clear. In this study, we investigated the therapeutic effects of indirect revascularization combined with EPC transplantation in rats with chronic cerebral ischemia.

Methods

Chronic cerebral ischemia was induced by bilateral internal carotid artery ligation (BICAL) in rats, and indirect revascularization by encephalo-myo-synangiosis (EMS) was performed 1 week later. During the EMS procedure, intramuscular injection of EPCs and the addition of stromal cell-derived factor 1 (SDF-1), and AMD3100, an SDF-1 inhibitor, were undertaken, respectively, to investigate their effects on indirect revascularization. Two weeks later, the cortical microcirculation, neuronal damage, and functional outcome were evaluated according to the microvasculature density and partial pressure of brain tissue oxygen (PbtO2), regional blood flow, expression of phosphorylated Tau (pTau), TUNEL staining and the rotarod performance test, respectively.

Results

The cortical microcirculation, according to PbtO2 and regional blood flow, was impaired 3 weeks after BICAL. These impairments were improved by the EMS procedure. The regional blood flow was further increased by the addition of SDF-1 and decreased by the addition of AMD3100. Intramuscular injection of EPCs further increased the regional blood flow as compared with the EMS group. The rotarod test results showed that the functional outcome was best in the EMS combined with EPC injection group. Western blot analysis showed that the EMS combined with EPC treatment group had significantly decreased expressions of phosphorylated Tau and phosphorylated glycogen synthase kinase 3 beta (Y216 of GSK-3β). pTau and TUNEL-positive cells were markedly increased at 3 weeks after BICAL induction. Furthermore, the groups treated with EMS combined with SDF-1 or EPCs exhibited marked decreases in the pTau expression and TUNEL-positive cells, whereas AMD3100 treatment increased TUNEL-positive cells.

Conclusion

The results of this study suggested that indirect revascularization ameliorated the cerebral ischemic changes. EPCs played a key role in augmenting the effect of indirect revascularization in the treatment of chronic cerebral ischemia.

Experimental Animal Models for Moyamoya Disease: A Species-Oriented Scoping Review

Moyamoya disease (MMD) is a rare cerebrovascular disease characterized by progressive stenosis of large intracranial arteries and a hazy network of basal collaterals called moyamoya vessels. The etiology and pathogenesis of MMD are still obscure. The biggest obstacles in the basic research of MMD are difficulty in obtaining specimens and the lack of an animal model. It is necessary to use appropriate and rationally designed animal models for the correct evaluation. Several animal models and methods have been developed to produce an effective MMD model, such as zebrafish, mice and rats, rabbits, primates, felines, canines, and peripheral blood cells, each with advantages and disadvantages. There are three mechanisms for developing animal models, including genetic, immunological/inflammatory, and ischemic animal models. This review aims to analyze the characteristics of currently available models, providing an overview of the animal models framework and the convenience of selecting model types for MMD research. It will be a great benefit to identify strategies for future model generations.

Study on the serum level of CoQ10B in patients with Moyamoya disease and its mechanism of affecting disease progression

BACKGROUND

At present, the etiology and pathogenesis of Moyamoya disease (MMD) are not completely clear. Patients are usually diagnosed after cerebrovascular events. Therefore, it is of great clinical significance to explore the predictive factors of MMD.

OBJECTIVE

This study aimed to investigate the serum level of CoQ10B, the amount of endothelial progenitor cells (EPCs), and mitochondrial function of EPCs in MMD patients.

METHODS

Forty-one MMD patients and 20 healthy controls were recruited in this study. Patients with MMD were divided into two groups: Ischemic type (n=23) and hemorrhagic type (n=18). Blood samples were collected from the antecubital vein and analyzed by CoQ10B ELISA and flow cytometry. Measures of mitochondrial function of EPCs include oxygen consumption rate (OCR), mitochondrial membrane potential, Ca2+ concentration, adenosine triphosphatases activity and ROS level.

RESULTS

The serum CoQ10B level in MMD patients was significantly lower than that in healthy controls (p<0.001). The relative number of EPCs in MMD patients was significantly higher than that in healthy controls (p<0.001). Moreover, the OCR, mitochondrial membrane potential and ATPase activity were decreased and the Ca2+ and reactive oxygen species levels were increased in MMD patients (p<0.001).

CONCLUSIONS

Our results showed obviously decreased serum CoQ10B level and increased EPCs number in patients with MMD compared with healthy patients, and the mitochondria function of EPCs in MMD patients was abnormal.

Moyamoya disease and syndrome: a review

Moyamoya disease is a chronic occlusive cerebrovascular disease that is non-inflammatory and non-atherosclerotic. It is characterized by endothelial hyperplasia and fibrosis of the intracranial portion of the carotid artery and its proximal branches, leading to progressive stenosis and occlusion, often clinically manifesting as ischemic or hemorrhagic stroke with high rates of morbidity and mortality. On cerebral angiography, the formation of collateral vessels has the appearance of a puff of smoke (moyamoya in Japanese), which became more conspicuous with the refinement of modern imaging techniques. When there is associated disease, it is known as moyamoya syndrome. Treatments are currently limited, although surgical revascularization may prevent ischemic events and preserve quality of life. In this review, we summarize recent advances in moyamoya disease, covering aspects of epidemiology, etiology, presentation, imaging, and treatment strategies.

Endothelial Progenitor Cells in Moyamoya Disease: Current Situation and Controversial Issues

Due to the lack of animal models and difficulty in obtaining specimens, the study of pathogenesis of moyamoya disease (MMD) almost stagnated. In recent years, endothelial progenitor cells (EPCs) have attracted more and more attention in vascular diseases due to their important role in neovascularization. With the aid of paradigms and methods in cardiovascular diseases research, people began to explore the role of EPCs in the processing of MMD. In the past decade, studies have shown that abnormalities in cell amounts and functions of EPCs were closely related to the vascular pathological changes in MMD. However, the lack of consistent criteria, such as isolation, cultivation, and identification standards, is also blocking the way forward. The goal of this review is to provide an overview of the current situation and controversial issues relevant to studies about EPCs in the pathogenesis and etiology of MMD.

Genetic and Proteomic Contributions to the Pathophysiology of Moyamoya Angiopathy and Related Vascular Diseases

RATIONALE

This literature review describes the pathophysiological mechanisms of the current classes of proteins, cells, genes, and signaling pathways relevant to moyamoya angiopathy (MA), along with future research directions and implementation of current knowledge in clinical practice.

OBJECTIVE

This article is intended for physicians diagnosing, treating, and researching MA.

METHODS AND RESULTS

References were identified using a PubMed/Medline systematic computerized search of the medical literature from January 1, 1957, through August 4, 2020, conducted by the authors, using the key words and various combinations of the key words "moyamoya disease," "moyamoya syndrome," "biomarker," "proteome," "genetics," "stroke," "angiogenesis," "cerebral arteriopathy," "pathophysiology," and "etiology." Relevant articles and supplemental basic science articles published in English were included. Intimal hyperplasia, medial thinning, irregular elastic lamina, and creation of moyamoya vessels are the end pathologies of many distinct molecular and genetic processes. Currently, 8 primary classes of proteins are implicated in the pathophysiology of MA: gene-mutation products, enzymes, growth factors, transcription factors, adhesion molecules, inflammatory/coagulation peptides, immune-related factors, and novel biomarker candidate proteins. We anticipate that this article will need to be updated in 5 years.

CONCLUSION

It is increasingly apparent that MA encompasses a variety of distinct pathophysiologic conditions. Continued research into biomarkers, genetics, and signaling pathways associated with MA will improve and refine our understanding of moyamoya's complex pathophysiology. Future efforts will benefit from multicenter studies, family-based analyses, comparative trials, and close collaboration between the clinical setting and laboratory research.

Vulnerability to shear stress caused by altered peri-endothelial matrix is a key feature of Moyamoya disease

Moyamoya disease (MMD) is characterized by progressive bilateral stenotic changes in the terminal portion of the internal carotid arteries. Although RNF213 was identified as a susceptibility gene for MMD, the exact pathogenesis remains unknown. Immunohistochemical analysis of autopsy specimens from a patient with MMD revealed marked accumulation of hyaluronan and chondroitin sulfate (CS) in the thickened intima of occlusive lesions of MMD. Hyaluronan synthase 2 was strongly expressed in endothelial progenitor cells in the thickened intima. Furthermore, MMD lesions showed minimal staining for CS and hyaluronan in the endothelium, in contrast to control endothelium showing positive staining for both. Glycosaminoglycans of endothelial cells derived from MMD and control induced pluripotent stem cells demonstrated a decreased amount of CS, especially sulfated CS, in MMD. A computational fluid dynamics model showed highest wall shear stress values in the terminal portion of the internal carotid artery, which is the predisposing region in MMD. Because the peri-endothelial extracellular matrix plays an important role in protection, cell adhesion and migration, an altered peri-endothelial matrix in MMD may contribute to endothelial vulnerability to wall shear stress. Invading endothelial progenitor cells repairing endothelial injury would produce excessive hyaluronan and CS in the intima, and cause vascular stenosis.

Vascular Remodeling in Moyamoya Angiopathy: From Peripheral Blood Mononuclear Cells to Endothelial Cells

The pathophysiological mechanisms of Moyamoya angiopathy (MA), which is a rare cerebrovascular condition characterized by recurrent ischemic/hemorrhagic strokes, are still largely unknown. An imbalance of vasculogenic/angiogenic mechanisms has been proposed as one possible disease aspect. Circulating endothelial progenitor cells (cEPCs) have been hypothesized to contribute to vascular remodeling of MA, but it remains unclear whether they might be considered a disease effect or have a role in disease pathogenesis. The aim of the present study was to provide a morphological, phenotypical, and functional characterization of the cEPCs from MA patients to uncover their role in the disease pathophysiology. cEPCs were identified from whole blood as CD45^dimCD34⁺CD133⁺ mononuclear cells. Morphological, biochemical, and functional assays were performed to characterize cEPCs. A significant reduced level of cEPCs was found in blood samples collected from a homogeneous group of adult (mean age 46.86 ± 11.7; 86.36% females), Caucasian, non-operated MA patients with respect to healthy donors (HD; p = 0.032). Since no difference in cEPC characteristics and functionality was observed between MA patients and HD, a defective recruitment mechanism could be involved in the disease pathophysiology. Collectively, our results suggest that cEPC level more than endothelial progenitor cell (EPC) functionality seems to be a potential marker of MA. The validation of our results on a larger population and the correlation with clinical data as well as the use of more complex cellular model could help our understanding of EPC role in MA pathophysiology.

High mobilization of CD133+/CD34+ cells expressing HIF-1α and SDF-1α in septic abdominal surgical patients

Background

The control of endothelial progenitor cells (CD133+/CD34+ EPCs) migrating from bone marrow to peripheral blood is not completely understood. Emerging evidence suggests that stromal cell-derived factor-1α (SDF-1α) mediates egression of EPCs from bone marrow, while the hypoxia inducible factor (HIF) transcriptional system regulates SDF-1α expression. Our study aimed to investigate the time course of circulating CD133+/CD34+ EPCs and its correlation with the expression of HIF-1α protein and SDF-1α in postoperative laparoscopic abdominal septic patients.

Methods

Postoperative patients were divided in control (C group) and septic group (S group) operated immediately after the diagnosis of sepsis/septic shock. Blood samples were collected at baseline (0), 1, 3 and 7 postoperative days for CD133+/CD34+ EPCs count expressing or not the HIF-1α and SDF-1α analysis.

Results

Thirty-two patients in S group and 39 in C group were analyzed. In C group CD133+/CD34+ EPCs count remained stable throughout the study period, increasing on day 7 (173 [0–421] /μl vs baseline: P = 0.04; vs day 1: P = 0.002). In S group CD133+/CD34+ EPCs count levels were higher on day 3 (vs day 1: P = 0.006 and day 7: P = 0.026). HIF-1α expressing CD133+/CD34+ EPCs count decreased on day 1 as compared with the other days in C group (day 0 vs 1: P = 0.003, days 3 and 7 vs 1: P = 0.008), while it was 321 [0–1418] /μl on day 3 (vs day 1; P = 0.004), and 400 [0–587] /μl on day 7 in S group. SDF-1α levels were higher not only on baseline but also on postoperative day 1 in S vs C group (219 [124–337] pg/ml vs 35 [27–325] pg/ml, respectively; P = 0.01).

Conclusion

Our results indicate that sepsis in abdominal laparoscopic patients might constitute an additional trigger of the EPCs mobilization as compared with non-septic surgical patients. A larger mobilization of CD133+/CD34+ EPCs, preceded by enhanced plasmatic SDF-1α, occurs in septic surgical patients regardless of HIF-1α expression therein.

Trial registration

ClinicalTrials.gov no. NCT02589535. Registered 28 October 2015.

Construction and Comprehensive Analysis of Dysregulated Long Noncoding RNA-Associated Competing Endogenous RNA Network in Moyamoya Disease

BACKGROUND

Moyamoya disease (MMD) is a rare cerebrovascular disease characterized by chronic progressive stenosis or occlusion of the bilateral internal carotid artery (ICA), the anterior cerebral artery (ACA), and the middle cerebral artery (MCA). MMD is secondary to the formation of an abnormal vascular network at the base of the skull. However, the etiology and pathogenesis of MMD remain poorly understood.

METHODS

A competing endogenous RNA (ceRNA) network was constructed by analyzing sample-matched messenger RNA (mRNA), long non-coding RNA (lncRNA), and microRNA (miRNA) expression profiles from MMD patients and control samples. Then, a protein-protein interaction (PPI) network was constructed to identify crucial genes associated with MMD. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) enrichment analyses were employed with the DAVID database to investigate the underlying functions of differentially expressed mRNAs (DEmRNAs) involved in the ceRNA network. CMap was used to identify potential small drug molecules.

RESULTS

A total of 94 miRNAs, 3649 lncRNAs, and 2294 mRNAs were differentially expressed between MMD patients and control samples. A synergistic ceRNA lncRNA-miRNA-mRNA regulatory network was constructed. Core regulatory miRNAs (miR-107 and miR-423-5p) and key mRNAs (STAT5B, FOSL2, CEBPB, and CXCL16) involved in the ceRNA network were identified. GO and KEGG analyses indicated that the DEmRNAs were involved in the regulation of the immune system and inflammation in MMD. Finally, two potential small molecule drugs, CAY-10415 and indirubin, were identified by CMap as candidate drugs for treating MMD.

CONCLUSIONS

The present study used bioinformatics analysis of candidate RNAs to identify a series of clearly altered miRNAs, lncRNAs, and mRNAs involved in MMD. Furthermore, a ceRNA lncRNA-miRNA-mRNA regulatory network was constructed, which provides insights into the novel molecular pathogenesis of MMD, thus giving promising clues for clinical therapy.

Influence of Inflammatory Disease on the Pathophysiology of Moyamoya Disease and Quasi-moyamoya Disease

Moyamoya disease is a unique cerebrovascular disease that is characterized by progressive bilateral stenotic alteration at the terminal portion of the internal carotid arteries. These changes induce the formation of an abnormal vascular network composed of collateral pathways known as moyamoya vessels. In quasi-moyamoya disease, a similar stenotic vascular abnormality is associated with an underlying disease, which is sometimes an inflammatory disease. Recent advances in moyamoya disease research implicate genetic background and immunological mediators, and postulate an association with inflammatory disease as a cause of, or progressive factor in, quasi-moyamoya disease. Although this disease has well-defined clinical and radiological characteristics, the role of inflammation has not been rigorously explored. Herein, we focused on reviewing two main themes: (1) molecular biology of inflammation in moyamoya disease, and (2) clinical significance of inflammation in quasi-moyamoya disease. We have summarized the findings of the former theme according to the following topics: (1) inflammatory biomarkers, (2) genetic background of inflammatory response, (3) endothelial progenitor cells, and (4) noncoding ribonucleic acids. Under the latter theme, we summarized the findings according to the following topics: (1) influence of inflammatory disease, (2) vascular remodeling, and (3) mechanisms gleaned from clinical cases. This review includes articles published up to February 2019 and provides novel insights for the treatment of the moyamoya disease and quasi-moyamoya disease.

Aberrant Promoter Hypomethylation of Sortilin 1: A Moyamoya Disease Biomarker

BACKGROUND AND PURPOSE

The pathogenesis of moyamoya disease (MMD) remains poorly understood, and no reliable molecular biomarkers for MMD have been identified to date. The present study aimed to identify epigenetic biomarkers for use in the diagnosis of MMD.

METHODS

We performed integrated analyses of gene expression profiles and DNA methylation profiles in endothelial colony forming cells (ECFCs) from three patients with MMD and two healthy individuals. Candidate gene mRNA expression and DNA methylation status were further validated using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and pyrosequencing analysis of an expanded ECFC sample set from nine patients with MMD and ten controls. We evaluated the diagnostic accuracy of the potential biomarkers identified here using receiver operating characteristic curve analyses and further measured major angiogenic factor expression levels using a tube formation assay and RT-qPCR.

RESULTS

Five candidate genes were selected via integrated analysis; all five were upregulated by hypomethylation of specific promoter CpG sites. After further validation in an expanded sample set, we identified a candidate biomarker gene, sortilin 1 (SORT1). DNA methylation status at a specific SORT1 promoter CpG site in ECFCs readily distinguished patients with MMD from the normal controls with high accuracy (area under the curve 0.98, sensitivity 83.33%, specificity 100%). Furthermore, SORT1 overexpression suppressed endothelial cell tube formation and modulated major angiogenic factor and matrix metalloproteinase-9 expression, implying SORT1 involvement in MMD pathogenesis.

CONCLUSION

s Our findings suggest that DNA methylation status at the SORT1 promoter CpG site may be a potential biomarker for MMD.

Progress in moyamoya disease

Moyamoya disease is characterized by progressive stenosis or occlusion of the intracranial portion of the internal carotid artery and their proximal branches, resulting in ischemic or hemorrhagic stroke with high rate of disability and even death. So far, available treatment strategies are quite limited, and novel intervention method is being explored. This review encapsulates current advances of moyamoya disease on the aspects of epidemiology, etiology, clinical features, imaging diagnosis and treatment. In addition, we also bring forward our conjecture, which needs to be testified by future research.

Circulating stem cells, HIF-1, and SDF-1 in septic abdominal surgical patients: randomized controlled study protocol

Background

Sepsis caused by complicated intra-abdominal infection is associated with high mortality. Loss of endothelial barrier integrity, inflammation, and impaired cellular oxygen have been shown to be primary contributors to sepsis. To date, little is known regarding the pathway for the mobilization of endothelial progenitor cells (EPCs) from the bone marrow in sepsis whereas stromal-cell-derived factor 1a (SDF-1a) and hypoxia inducible factor 1 (HIF-1) seem to have a role in the EPC response to hypoxic microenvironments.

The aims of the study are: (a) to determine the time course of the levels of circulating EPCs (CD133/CD34), SDF-1a, and HIF-1 in septic patients undergoing major abdominal surgery (group S), (b) to investigate the relationship between CD133/CD34, HIF-1, and SDF-1a, and (c) to investigate the relationship of these factors with the outcome of group S patients treated with standard conventional therapy alone (CT) or with the addition of extracorporeal hemoperfusion therapy (HCT).

Methods/design

Patients undergoing major abdominal surgery will be allocated into groups: postoperative non-septic patients in an emergency surgical ward (group C) and postoperative septic patients in an intensive care unit (group S). The latter will be randomized to receive CT alone (S1) or with HCT (S2). Healthy volunteers (group H) will be recruited at University Hospital Foggia.

Peripheral blood (PB) samples will be collected preoperatively (T0), at 24 h (T1), 72 h (T2), 7 (T3), and 10 (T4) postoperative days in groups S and C, and at T0 in group H. The CD34/133 cells and HIF-1 counts will be determined by flow cytometer analysis. The concentration of SDF-1a in plasma will be calculated by enzyme-linked immunosorbent assay analysis (ELISA).

Discussion

This prospective randomized clinical trial is designed to investigate circulating stem cells, levels of HIF-1 and SDF-1a, and their interrelationship in septic postoperative abdominal surgical patients treated with CT alone or with HCT. The rationale is that an integrated understanding of the role of hypoxia-related factors and EPCs in PB of septic patients could indicate which molecular processes need to be regulated to recover the innate immunity homeostasis. Understanding the function of EPCs in sepsis may provide innovative diagnostic and therapeutic approaches to improve the prognosis of this syndrome.

Trial registration

ClinicalTrials.gov: NCT02589535. Registered on 28 October 2015.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2556-0) contains supplementary material, which is available to authorized users.

Low-dose methotrexate in sickle-cell disease: a pilot study with rationale borrowed from rheumatoid arthritis

Background

Inflammation is a major feature of sickle cell disease (SCD). Low-dose methotrexate (MTX) has long been used in chronic inflammatory diseases. This pilot study examined the MTX effect on acute vaso-occlusive pain crises (VOC) in SCD patients.

Methods

Fourteen adults on hydroxyurea with severe and refractory VOC received one intramuscular injection of 10 mg of MTX per week for 12 weeks. A single weekly dose of 5 mg of leucovorin was administered orally 48 h after each MTX injection. The primary outcome was reduction in number/intensity of acute pain episodes. The secondary outcomes were improvement of quality of life (QOL) and reduction of the inflammatory status.

Results

MTX did not significantly change the median VOC frequency (12 before vs 10.5 during treatment, P = 0.6240) or the median McGill pain index (45 at week 0 vs 39.5 at week 12, P = 0.9311). However, there was a decrease of ≥50% in chronic pain resulting from avascular osteonecrosis (AVN) in 5 out of 7 patients with radiologic evidence of AVN, with the perception of longer pain-free periods. There was a 44.4% median gain in physical function in the SF-36 QOL questionnaire (P = 0.0198). MTX treatment up-regulated two C-X-C motif chemokines (CXCL), CXCL10 (P = 0.0463) and CXCL12 (P < 0.0001), without significant effect on 14 additional plasma inflammatory markers. Adverse events: One individual had fever of unknown origin. Respiratory tract infections were recorded in five patients. Among the latter, one also had dengue fever and another had a central venous line infection and died of pneumonia and septic shock. Three patients with previous history of hydroxyurea-induced hematological toxicity developed low blood platelet counts while receiving simultaneously MTX and hydroxyurea.

Conclusions

Although MTX did not reduce acute VOC frequency/intensity, it decreased chronic pain and led to QOL improvement.

Trial registrationhttp://www.who.int/ictrp/en/ and http://www.ensaiosclinicos.gov.br, RBR-2s9xvn, 19 December 2016, retrospectively registered

Electronic supplementary material

The online version of this article (doi:10.1186/s40164-017-0078-1) contains supplementary material, which is available to authorized users.

Moyamoya Biomarkers

Moyamoya disease (MMD) is an arteriopathy of the intracranial circulation predominantly affecting the branches of the internal carotid arteries. Heterogeneity in presentation, progression and response to therapy has prompted intense study to improve the diagnosis and prognosis of this disease. Recent progress in the development of moyamoya-related biomarkers has stimulated marked interest in this field. Biomarkers can be defined as biologically derived agents-such as specific molecules or unique patterns on imaging-that can identify the presence of disease or help to predict its course. This article reviews the current categories of biomarkers relevant to MMD-including proteins, cells and genes-along with potential limitations and applications for their use.

Review of past research and current concepts on the etiology of moyamoya disease

Research on moyamoya disease has progressed remarkably in the past several decades. Indeed, many new facts concerning the epidemiology of the disease have been revealed and surgical treatments have been drastically improved. However, despite extensive research, the mechanism of moyamoya disease is still unknown. Consequently, the cardinal treatment of this disease has not yet been developed. For further clarification of its etiology, innovative studies are therefore indispensable. The aim of this paper is to review research on the pathogenesis of moyamoya disease to identify milestones in the direction of its true solution. Many hypotheses of the pathogenesis of moyamoya disease have been proposed in the past half century, including infection (viral and bacterial), autoimmune disorders, proteins abnormality, and gene abnormality. Some of these are now considered to be historical achievements. Others, however, can be still subjected to contemporary research. Currently, several genetic abnormalities are considered to offer the most probable hypothesis. In addition, interesting papers have been presented on the role of the endothelial progenitor cell on the pathogenesis of moyamoya disease. Intuitively, however, it appears that a single theory cannot always explain the pathogenesis of this disease adequately. In other words, the complex mechanism of several factors may comprehensively explain the formation of moyamoya disease. The "double hit hypothesis" is probably the best explanation for the complicated pathology and epidemiology of this disease.

Impacts and interactions of PDGFRB, MMP-3, TIMP-2, and RNF213 polymorphisms on the risk of Moyamoya disease in Han Chinese human subjects

Polymorphisms of PDGFRB, MMP-3, TIMP-2, RNF213, TGFB1, Raptor and eNOS genes have been associated with Moyamoya disease (MMD) separately in studies, but their interactions on MMD have never been evaluated in one study. This study enrolled 96 MMD patients and 96 controls to evaluate the contributions and interactions of these polymorphisms on MMD in Chinese Hans. After genotyping, five polymorphisms loci were deemed suitable for analysis, rs3828610 in PDGFRB, rs3025058 in MMP-3, rs8179090 in TIMP-2, rs112735431 and rs148731719 in RNF213. Interactions of different loci on MMD were evaluated by multifactor dimensionality reduction (MDR) method. Significantly higher frequencies of A allele and G/A genotype of rs112735431 in RNF213 were observed in MMD patients compared with controls (P=0.011; P=0.018, respectively). In the dominant model, G/A genotype of rs112735431 was associated with increased risk of MMD (P=0.018). A higher frequency of G allele and G/G genotype of rs148731719 in RNF213 gene in patient than control group (P<0.001; P<0.01, respectively) was also detected. No significant association between MMD and other three loci (P>0.05) was detected. MDR analysis failed to detect any significant interaction among these five loci in the occurrence of MMD (P>0.05), but the combination of three loci (rs112735431 in RNF213, rs3828610 in PDGFRB, rs3025058 in MMP-3) could have the maximum testing accuracy (57.29%) and cross-validation consistency (10/10). The results indicated that RNF213 rs112735431 and rs148731719 may exert a significant influence on MMD occurrence. Compared with this overwhelming effect, the influences of PDGFRB, MMP-3, and TIMP-2 on MMD may be unremarkable in Chinese Hans. There may be no prominent interaction among these five gene polymorphisms on the occurrence of MMD.

Decreased levels of angiogenic growth factors in intracranial atherosclerotic disease despite severity-related increase in endothelial progenitor cell counts

BACKGROUND

Intracranial atherosclerotic disease (ICAD) is an important cause of ischemic stroke (IS) and endothelial dysfunction plays a critical role in its onset and progression. Endothelial progenitor cells (EPCs) and endothelial production of angiogenic growth factors (AGFs) may play an essential role in this process. This study investigated the association of EPCs and AGFs with ICAD severity.

METHODS

A total of 42 patients who had experienced a transient ischemic attack (TIA) or IS attributable to symptomatic ICAD were included. Clinical and neurosonological evaluations were conducted between 2.4 and 8.7 years after the initial cerebrovascular event. Severe ICAD was defined as the presence of at least 1 severe intracranial stenosis, and extensive ICAD as 3 or more intracranial stenoses. Blood samples were obtained to determine EPC levels using flow cytometry (CD34+KDR+ cells), and the plasma levels of several growth factors were assessed with a protein array (Searchlight(®)). Twenty-two individuals without cerebrovascular disease and with normal ultrasonographic examination were also included.

RESULTS

No difference in the count of circulating EPCs was found between patients and controls, and a moderate increase in the number of EPCs/ml was noted in patients with extensive ICAD (p = 0.05). Patients presented decreased levels of fibroblast growth factor (FGF), vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF-BB) compared with controls (p = 0.002, p = 0.079 and p = 0.061, respectively). Higher levels of FGF, VEGF and PDGF-BB were found in patients with severe ICAD (p = 0.007, p = 0.07 and p = 0.07, respectively), but there was no correlation between any AGFs and EPCs.

CONCLUSIONS

Symptomatic ICAD patients have decreased levels of AGFs with no correlation to the number of circulating EPCs, while patients with severe ICAD have higher levels of EPCs, FGF, VEGF and PDGF-BBs. This suggests that reduced EPC and proangiogenic factor production capacity is implicated in ICAD pathogenesis, while the more severe forms of chronic brain hypoperfusion in ICAD patients might stimulate EPC mobilization and AGF production.

SDF-1α induces angiogenesis after traumatic brain injury

This study aimed to investigate the effects of SDF-1α on brain angiogenesis and neurological functional recovery in rats after traumatic brain injury (TBI) and the potentially involved mechanisms. Youth male Wistar rats were injured via lateral fluid percussion injury and then randomly divided into one of 3 groups: I. vehicle treated group; II. SDF-1α neutralizing antibody treated group and III. rhSDF-1α treated group. rhSDF-1α and its neutralizing antibody or normal saline were administered to the brain penumbra via stereotactic injection 30min after TBI. Modified neurological severity score (mNSS) and Morris water maze (MWM) test were used to assess the neurologic functional recovery (n=6/group). 14days after injury, animals were euthanized and brain tissues were collected for quantitative real time polymerase chain reaction (qRT-PCR) (n=6/group) and immunohistochemistry (n=6/group) analysis. mNSS and MWM test indicated distinct amelioration of neurological disability in rhSDF-1α group(P<0.05). Microvessel density (MVD) of rhSDF-1α treated animals was remarkably increased around the injured area. On the contrary, MVD of the SDF-1α antibody administrated group was significantly decreased compared to that of vehicle treated animals (P<0.05). The mNSS and MVD had significant negative correlation as tested by Spearman rank correlation coefficient. Immunofluorescence staining showed that CD34 and CXCR4 co-expressed on microvessels. The rhSDF-1α treated animals had greater, contrarily, the SDF-1α antibody treated animals had lesser number of double positive microvessels compared to that of vehicle treated animals. The mRNA expression of CD34 and CXCR4 was obviously elevated in the rhSDF-1α administration group, conversely, declined in SDF-1α antibody treated animals around the injured area compared with that of the vehicle treatment group (P<0.05). These data indicated that SDF-1α could induce angiogenesis after TBI, potentially via SDF-1/CXCR4 axis.