OBJECTIVES: Neurodegenerative diseases are closely associated with myelin loss, and the proliferation and differentiation of oligodendrocyte precursor cells (OPCs) are crucial to remyelination. However, the regulatory mechanisms involved remain incompletely understood. This study aims to investigate how astrocytes (ASTs) regulate the secretion of chitinase-3-like protein 1 (CHI3L1) via connexin 47 (Cx47)-mediated exosome signaling, and its subsequent effect on OPC proliferation. METHODS: Primary cells were isolated from postnatal day 1 Sprague-Dawley (P1SD) rats to establish 3 culture conditions: OPCs alone (Group O), OPCs in direct contact with ASTs (Group C), and OPCs cultured with AST-conditioned medium (Group A). Cellular morphology and proliferation were assessed using optical microscopy, 5-ethynyl-2'- deoxyuridine (EdU) incorporation, and flow cytometry. RNA sequencing (RNA-Seq) and bioinformatics analysis (BA) were conducted to identify differentially expressed genes (DEGs) among groups. Protein expression and cell cycle distribution were analyzed by Western blotting (WB) and flow cytometry. Exosomes were isolated and purified via differential centrifugation, characterized by nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM), and CHI3L1 expression in exosomes was verified via WB. Cx47 was silenced using small interfering RNA (siRNA) to evaluate its effect on OPC proliferation and exosome secretion. Artificial exosomes were constructed by encapsulating CHI3L1 in single unilamellar vesicles (SUVs), whose structure and size were validated by NTA and TEM. Following Cx47 knockdown, artificial exosomes were added back, and OPC proliferation was assessed via flow cytometry and EdU assay. RESULTS: Direct co-cultured with ASTs (Group C) resulted in significantly enhanced OPC proliferation compared to the Group O and Group A (P<0.05). RNA-Seq and WB analyses revealed that ASTs promote OPC proliferation and exosome secretion enriched in CHI3L1 through Cx47. Cx47 knockdown by siRNA led to significant decreases in OPC proliferation and exosome release (P<0.05). The inhibitory effect of Cx47 silencing on OPC proliferation was partially reversed by supplementation with either isolated exosomes or exogenous CHI3L1. CONCLUSIONS This study reveals a novel mechanism by which ASTs regulate OPC proliferation: Through direct contact, ASTs enhance the secretion of CHI3L1-rich exosomes via Cx47, thereby converting intercellular contact signals into secretory signals that promote OPC proliferation. As a key exosomal molecule, CHI3L1 may play an important role in neural function and remyelination and warrants further investigation.
Animals ; Exosomes/metabolism* ; Cell Proliferation ; Rats, Sprague-Dawley ; Rats ; Connexins/genetics* ; Oligodendrocyte Precursor Cells/metabolism* ; Astrocytes/metabolism* ; Chitinase-3-Like Protein 1/metabolism* ; Cells, Cultured ; Cell Differentiation

OBJECTIVES: To explore the role and potential mechanisms of chitinase-3-like protein 1 (CHI3L1) in coronary artery lesions in a mouse model of Kawasaki disease (KD)-like vasculitis. METHODS: Four-week-old male SPF-grade C57BL/6 mice were randomly divided into a control group and a model group, with 10 mice in each group. The model group mice were intraperitoneally injected with 0.5 mL of lactobacillus casei cell wall extract (LCWE) to establish a mouse model of KD-like vasculitis, while the control group mice were injected with an equal volume of normal saline. The general conditions of the mice were observed on the 3rd, 7th, and 14th day after injection. Changes in coronary artery tissue pathology were observed using hematoxylin-eosin staining. The level of CHI3L1 in mouse serum was measured by enzyme-linked immunosorbent assay. Immunofluorescence staining was used to detect the expression and localization of CHI3L1, von Willebrand factor (vWF), and α-smooth muscle actin (α-SMA) in coronary artery tissue. Western blot analysis was used to detect the expression of CHI3L1, vWF, vascular endothelial cadherin (VE cadherin), Caspase-3, B cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax), nuclear factor κB (NF-κB), and phosphorylated NF-κB (p-NF-κB) in coronary artery tissue. RESULTS: The serum level of CHI3L1 in the model group was significantly higher than that in the control group (P<0.05). Compared to the control group, the expression of CHI3L1 in the coronary artery tissue was higher, while the expression of vWF was lower in the model group. The relative expression levels of CHI3L1, Bax, Caspase-3, NF-κB, and p-NF-κB were significantly higher in the model group than in the control group (P<0.05). The relative expression levels of vWF, VE cadherin, and Bcl-2 were lower in the model group than in the control group (P<0.05). CONCLUSIONS In the LCWE-induced mouse model of KD-like vasculitis, the expression levels of CHI3L1 in serum and coronary arteries increase, and it may play a role in coronary artery lesions through endothelial cell apoptosis mediated by inflammatory reactions.
Male ; Animals ; Mice ; Mucocutaneous Lymph Node Syndrome/pathology* ; Coronary Vessels/pathology* ; NF-kappa B ; Caspase 3/metabolism* ; bcl-2-Associated X Protein/metabolism* ; Chitinase-3-Like Protein 1 ; von Willebrand Factor/metabolism* ; Mice, Inbred C57BL ; Cadherins

OBJECTIVE: To evaluate the value of chitinase-like protein YKL-40 in bronchoalveolar lavage fluid (BALF) for predicting refractory METHODS: A total of 50 children with common RESULTS: Compared with the common MPP group, the RMPP group had significantly higher incidence rates of fever, shortness of breath, lung consolidation, and pleural effusion ( CONCLUSIONS There is an increase in the level of YKL-40 in BALF in children with RMPP, and the level of YKL-40 in BALF has a certain value for predicting RMPP.
Bronchoalveolar Lavage Fluid ; Child ; Chitinase-3-Like Protein 1 ; Chitinases ; Humans ; Mycoplasma pneumoniae ; Pneumonia, Mycoplasma/diagnosis*

OBJECTIVE: To investigate the value of serum and bronchoalveolar lavage fluid (BALF) chitinase-3-like-1 protein (YKL-40) in the diagnosis of anti-melanoma differentiation-associated gene 5 (MDA5)-positive dermatomyositis (DM) patients complicated with serious pulmonary injury, including rapidly progressive interstitial lung disease (RP-ILD) and pulmonary infection. METHODS: Anti-MDA5 antibodies positive patients with DM who were hospitalized in the Department of Rheumatology of China-Japan Friendship Hospital from 2013 to 2018 were involved in this study. Demographic information, clinical, laboratory and imaging data were retrospectively collected. ELISA was used to detect the serum and BALF levels of YKL-40. The receiver operating characteristic (ROC) curve was drawn, and the area under ROC curve (AUC) was used to evaluate the diagnostic value of serum YKL-40 for pulmonary injury.Interstitial lung disease (ILD) was confirmed by chest high-resolution CT (HRCT). RP-ILD was defined as progressive respiratory symptoms such as dyspnea and hypoxemia within 3 months, and/or deterioration of interstitial changes or appearace of new pulmonary interstitial lesions on chest HRCT. Pulmonary infection was considered as positive pathogens detected in qualified sputum, blood, bronchoalveolar lavage fluid or lung biopsy specimens. RESULTS: A total of 168 anti-MDA5-positive DM patients including 108 females and 60 males were enrolled in the study. Of these patients, 154 had ILD, and 66(39.3%) of them presented RP-ILD. Seventy patients with pulmonary infection were confirmed by etiology. In the patients with RP-ILD, 39 (59.1%) of them were complicated with pulmonary infection. While only 31 cases(30.4%) had pulmonary infection in the non-RP-ILD patients. The incidence of pulmonary infection in the patients with RP-ILD was significantly higher than that of those with non-RP-ILD (P < 0.001). The serum YKL-40 levels in the RP-ILD patients with pulmonary infection were the highest compared with RP-ILD without pulmonary infection, non-RP-ILD with pulmonary infection and non-RP-ILD without pulmonary infection groups among all the patients [83 (42-142) vs. 42 (21-91) vs. 43 (24-79) vs. 38 (22-69), P < 0.01].The sensitivity, specificity and AUC of serum YKL-40 in the diagnosis of RP-ILD complicated with pulmonary infection were 75%, 67%, and 0.72, respectively. The AUC of diagnosed of anti-MDA5 positive DM patients complicated with RP-ILD and pulmonary infection was higher than that of patients complicated with only RP-ILD and only pulmonary infection (0.72 vs. 0.54 and 0.55, Z=2.10 and 2.11, P < 0.05). CONCLUSION The prognosis of anti-MDA5-positive DM patients with RP-ILD and pulmonary infection were poor. Serum YKL-40 level can be used as a helpful tool for the diagnosis of coexistence of these conditions in the patients.
Chitinase-3-Like Protein 1 ; Dermatomyositis/complications* ; Female ; Humans ; Lung Diseases, Interstitial/diagnosis* ; Lung Injury ; Male ; Retrospective Studies

OBJECTIVE: To investigate the association of YKL-40 in bronchoalveolar lavage fluid (BALF) with airway damage in children with Mycoplasma pneumoniae pneumonia (MPP). METHODS: A total of 60 children with MPP who were admitted to the hospital were enrolled as the MPP group, and 12 children with bronchial foreign bodies were enrolled as the control group. According to the imaging findings, the MPP group was further divided into 3 subgroups: pulmonary patchy shadow (n=34), pulmonary consolidation (n=19) and pulmonary ground-glass opacity (n=7). According to the bronchoscopic findings, the MPP group was further divided into 3 subgroups: mucosal congestion/edema (n=38), mucous secretion (n=18) and plastic bronchitis (n=4). The clinical manifestations and laboratory characteristics of the children with MPP were analyzed, the expression of YKL-40 in BALF was measured. RESULTS: The MPP group had significantly higher levels of serum lactate dehydrogenase and BALF YKL-40 than the control group (P<0.05). The pulmonary consolidation subgroup had significantly higher levels of serum C-reactive protein and lactate dehydrogenase than the pulmonary patchy shadow subgroup (P<0.05), and the pulmonary consolidation and pulmonary ground-glass opacity subgroups had a significantly higher level of BALF YKL-40 than the pulmonary patchy shadow subgroup (P<0.05). The plastic bronchitis subgroup had a significantly higher level of BALF YKL-40 than the mucous secretion and mucosal congestion/edema subgroups (P<0.05). The mucous secretion and plastic bronchitis subgroups had a significantly higher proportion of children with shortness of breath than the mucosal congestion/edema subgroup (P<0.05). The plastic bronchitis subgroup had significantly higher serum levels of C-reactive protein and lactate dehydrogenase than the mucosal congestion/edema subgroup (P<0.05). CONCLUSIONS The level of BALF YKL-40 is associated with airway damage and disease severity in children with MPP.
Bronchoalveolar Lavage Fluid ; C-Reactive Protein ; Child ; Chitinase-3-Like Protein 1 ; Humans ; Mycoplasma pneumoniae ; Pneumonia, Mycoplasma

BackgroundAcute coronary syndrome (ACS) is closely related to unstable plaques and secondary thrombosis. The inflammatory cells in plaques and their inflammatory products may be the cause for plaque instability and ruptures. The study aimed to disclose the changes of inflammatory factors including serum intracellular adhesion molecule-1 (ICAM-1), chitinase-3-like protein 1 (YKL-40), and lipoprotein-associated phospholipase A2 (Lp-PLA2) in patients with ACS and its clinical significance.

MethodsA total of 120 patients with coronary heart disease (CHD) were categorized into 2 groups: 69 with ACS and 51 with stable angina pectoris (SAP); 20 patients with chest pain and normal angiography served as a control group. The 120 patients with CHD were categorized into single-vessel disease group, double-vessel disease group, and three-vessel disease group based on the number of coronary artery stenosis. The severity of coronary artery stenosis was quantified based on coronary angiography using Gensini score. They were further divided into mild CHD group with its Gensini score <26 (n = 36), moderate CHD group with its Gensini score being 26-54 (n = 48) and severe CHD group with its Gensini score >54 (n = 36). Serum levels of ICAM-1, YKL-40, and Lp-PLA2 of different groups were determined by enzyme-linked immunosorbent assay. Correlation between ICAM-1, YKL-40, Lp-PLA2, and Gensini score was analyzed.

ResultsThe levels of serum inflammatory factors ICAM-1, YKL-40, and Lp-PLA2 were significantly higher in the ACS group than those in control group and SAP group (all P < 0.05); and compared with control group, no significant difference was observed in terms of the serum ICAM-1, YKL-40, and Lp-PLA2 levels in the SAP group (P > 0.05).The levels of serum ICAM-1, YKL-40, and Lp-PLA2 were not significantly different among control group, single-vessel disease group, double-vessel disease group, and three-vessel disease group (all P > 0.05). The levels of serum ICAM-1, YKL-40, and Lp-PLA2 were not significantly different among control group, mild CHD group (Gensini score <26), moderate CHD group (Gensini score 26-54), and severe CHD group (Gensini score >54) (all P > 0.05). Nonparametric Spearman correlation analysis showed that the levels of serum ICAM-1, YKL-40, and Lp-PLA2 were not correlated with the Gensini score in CHD patients (r = 0.093, r = -0.149, and r = -0.085, all P > 0.05; respectively).

ConclusionsThe serum levels of ICAM-1, YKL-40, and Lp-PLA2 were correlated with different clinical types of CHD, but not well correlated the severity and extent of artery stenosis, suggesting that ICAM-1, YKL-40, and Lp-PLA2 might be involved in occurrence of instability of atherosclerotic plaque, and might reflect the severity of CHD mostly through reflecting the plaque stability.

1-Alkyl-2-acetylglycerophosphocholine Esterase ; metabolism ; Acute Coronary Syndrome ; blood ; immunology ; metabolism ; Adult ; Aged ; Chitinase-3-Like Protein 1 ; metabolism ; Coronary Angiography ; Coronary Disease ; blood ; immunology ; metabolism ; Humans ; Intercellular Adhesion Molecule-1 ; metabolism ; Middle Aged

OBJECTIVETo investigate the changes in serum YKL-40 level and humoral immune function and their significance in children with recurrent pneumonia.

METHODSBlood samples were collected from 30 children with recurrent pneumonia (recurrent pneumonia group), 30 children with acute pneumonia (acute pneumonia group), and 30 healthy children (control group). Serum YKL-40 levels were measured by enzyme-linked immunosorbent assay. The correlation between serum YKL-40 level and laboratory indices related to humoral immune function was analyzed. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of serum YKL-40 level for recurrent pneumonia.

RESULTSThe recurrent pneumonia group had a significantly higher serum YKL-40 level than the acute pneumonia and control groups (P<0.05). The acute pneumonia group had a significantly higher serum YKL-40 level than the control group (P<0.05). Serum levels of IgG and complement 4 in the recurrent pneumonia group were significantly lower than in the acute pneumonia group (P<0.05). Serum YKL-40 level was negatively correlated with serum IgG level (r=-0.309, P=0.047) and serum complement 4 level (r=-0.324, P=0.039). The area under the ROC curve of serum YKL-40 level for diagnosing recurrent pneumonia was 0.958 (95%CI: 0.921-0.994).

CONCLUSIONSHumoral immune function is low in children with recurrent pneumonia. Serum YKL-40 may be involved in the occurrence of recurrent pneumonia and can be used as a reference index for diagnosing recurrent pneumonia.

Child, Preschool ; Chitinase-3-Like Protein 1 ; blood ; Complement C4 ; analysis ; Female ; Humans ; Immunity, Humoral ; Immunoglobulin G ; blood ; Male ; Pneumonia ; immunology ; Recurrence

OBJECTIVETo investigate the association between CHI3L1 single nucleotide polymorphisms (SNPs) and the susceptibility to childhood asthma.

METHODSA total of 316 children diagnosed with asthma between January 2011 and October 2013 and 297 healthy children were selected as asthma group and control group respectively. Peripheral blood samples were collected from all subjects. Chemiluminescence and flow cytometry were applied to measure total IgE level and the percentage of eosinophils. ELISA was used to measure YKL-40 level. Genomic DNA was extracted from peripheral blood hemocytes, and the genotype and allele frequencies at CHI3L1 SNPs rs4950928, rs10399805, and rs883125 were determined by MALDI-TOP mass spectrometry.

RESULTSThe total IgE and YKL-40 levels were significantly higher in the asthma group than in the control group (P<0.05), while the percentage of eosinophils showed no significant difference between the two groups (P>0.05). The frequency of GG genotype at rs883125 in the asthma group was significantly higher than that in the control group (P<0.05). For rs4950928, the asthma group had a significantly lower frequency of CC genotype (P<0.05) but a significantly higher frequency of CG genotype (P<0.05) compared with the control group. In the asthma group, the patients with GG and CG genotypes at rs4950928 had significantly increased total IgE and YKL-40 levels compared with those with CC genotype at this locus (P<0.05).

CONCLUSIONSYKL-40 is a potential molecular biomarker for the primary diagnosis of childhood asthma. CHI3L1 SNPs rs4950928 and rs883125 may be associated with childhood asthma. G allele at rs4950928 may increase the risk of childhood asthma.

Adipokines ; blood ; genetics ; Asthma ; etiology ; genetics ; Child ; Child, Preschool ; Chitinase-3-Like Protein 1 ; Female ; Genetic Predisposition to Disease ; Humans ; Immunoglobulin E ; blood ; Infant ; Lectins ; blood ; genetics ; Male ; Polymorphism, Single Nucleotide

OBJECTIVE: This study intends to preliminarily discuss the expression and the clinical meaning of serum YKL-40 in anaphylactic rhinitis by comparing the different expressions of serum YKL-40 in types of anaphylactic rhinitis, and to preliminarily discuss possible mechanism of having anaphylactic rhinitis involved with serum YKL-40 by associating it with serum IL-4 and IFN-γ in anaphylactic rhinitis. METHOD: Firstly, each select 20 people in our hospital who have anaphylactic rhinitis respectively according to different levels--mild intermittent, mild persistent, moderate-severe interminttent, moderate-severe persistent as the experimental groups, while 20 healthy people as the nomal control. Secondly, test the levels of serum YKL-40, IL-4 and IFN-γ respectively in each group by the ELISA method. Thirdly, statistically analyze and discuss the collected data. RESULT: (1) There was a rise in the expression of serum YKL-40 between the experimental groups and the nomal control group, which contained a statistical significance (P < 0.05). There was a rise in the expression of serum YKL-40 between the mild persistent group and mild intermittent group, which contained a statistical significance (P < 0.05), as well as between the moderate-severe persistent group and the moderate-severe intermittent group (P < 0.05), while there was no significant difference in expression of serum YKL-40 between the mild intermittent group and the moderate-severe intermittent group, as well as between the mild persistent group and the moderate-severe persistent group (P > 0.05). (2) There was a rise in the expression of serum IL-4 between the experimental groups and the nomal control group, which contained a statistical significance (P < 0.05), while there was no significant difference between each experimental group (P > 0.05). (3) There was a reduction in the expression of serum IL-4 be- tween the experimental groups and the nomal control group, which contained a statistical significance (P < 0.05), while there was no significant difference between each experimental group (P > 0.05). (4) The corelation between serum YKL-40 and IL-4 in anaphylactic rhinitis was positive, while the corelation between serum YKL-40 and IFN-γ was negative. CONCLUSION (1) Allergic rhinitis serum YKL-40 expression was increased. The corelation between serum YKL-40 and IL-4 in anaphylactic rhinitis was positive, while the corelation between serum YKL-40 and IFN-γ was negative,suggesting that YKL-40 may regulate the differentiation of Th cells, Promote Th1 to Th2 immune shift, through this mechanism involved in the pathogenesis of allergic rhinitis. (2) Compared with patients with intermittent allergic rhinitis, persistent allergic rhinitis serum YKL-40 expression was increased, suggesting that YKL-40 may promote the continuous attacks of the symptoms of allergic rhinitis.
Adipokines ; blood ; Case-Control Studies ; Chitinase-3-Like Protein 1 ; Humans ; Interferon-gamma ; blood ; Interleukin-4 ; blood ; Lectins ; blood ; Rhinitis, Allergic ; blood

OBJECTIVETo investigate the changes of serum levels of chitinase-3-like-1 protein (YKL-40) and high-sensitivity C-reactive protein (hs-CRP) in patients with non-ST segment elevation acute coronary syndrome (ACS), to explore its correlation with its severity, and to observe the effects of Guizhi Fuling Decoction (GFD) on levels of blood lipids, YKL-40, and hs-CRP.

METHODSRecruited were 72 patients with unstable angina (UA) or non-ST segment elevation myocardial infarction (NSTEMI) at Department of Integrative Medicine, First Affiliated Hospital of Xinxiang Medical College from August 2010 to June 2011. They were randomly assigned to the treatment group (36 cases) and the control group (36 cases). All patients were treated by routine treatment, but patients in the treatment group took GFD additionally. The course of treatment was four weeks. According to the severity degree, all patients were graded to four ranks: low-risk group of UA, medium-risk group of UA, high-risk group of UA, and NSTEMI. The levels of YKL-40 and hs-CRP, and the correlation of severity degree were analyzed. Before and after treatment levels of triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) were measured. Before treatment, at two weeks, and after treatment the serum levels of YKL-40 and hs-CRP were detected. The relationship of YKL-40, hs-CRP and the severity of the disease were analyzed.

RESULTSLevels of YKL-40 and hs-CRP were positively correlated with the severity of the disease respectively (r = 0.729, P < 0.05; r = 0.655, P < 0.05). The positive correlation also existed between YKL-40 and hs-CRP (r = 0.848, P < 0.05). There was no statistical difference in the levels of blood lipids, YKL-40, or hs-CRP between the two groups before treatment (P > 0.05). Compared with before treatment, the levels of YKL-40 and hs-CRP significantly decreased in both groups after two weeks of treatment (P < 0.05). The levels of TG, TC, LDL-C, YKL-40, and hs-CRP significantly decreased, while the HDL-C level increased in both groups after treatment (P < 0.05). The level of HDL-C in the treatment group was higher, while levels of YKL-40 and hs-CRP were lower after treatment, when compared with the control group (all P < 0.05).

CONCLUSIONOn the basis of anti-inflammation and adjusting blood lipids by Western medicine, GFD could further reduce the serum levels of YKL-40 and hs-CRP of ACS patients, elevate the HDL-C level, and play anti-atherosclerosis effects.

Acute Coronary Syndrome ; blood ; drug therapy ; physiopathology ; Adipokines ; blood ; Aged ; C-Reactive Protein ; metabolism ; Chitinase-3-Like Protein 1 ; Cholesterol, HDL ; blood ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Female ; Humans ; Lectins ; blood ; Male ; Middle Aged ; Triglycerides ; blood