Effect of human umbilical cord mesenchymal stem cells in treatment of mice with liver fibrosis and its mechanism / 临床肝胆病杂志

ObjectiveTo investigate the effect of human umbilical cord mesenchymal stem cells （hUCMSCs） in the treatment of mice with liver fibrosis and its mechanism. MethodsA total of 18 specific pathogen-free C57BL/6 mice， aged 6 weeks， were selected and divided into control group （n=6）， carbon tetrachloride （CCl4） model group （CCl4 group， n=6）， and hUCMSCs treatment group （MSC group， n=6） using a random number table. The mice in the CCl4 group and the MSC group were given intraperitoneal injection of CCl4 solution to establish a mouse model of liver fibrosis， while those in the control group were injected with the same dose of corn oil， and the mice in the MSC group were injected with hUCMSCs via the caudal vein during the injection of CCl4. At the end of week 8， mouse serum was collected， and the mice were sacrificed to collect and fix the liver. Enzyme-linked immunosorbent assay was used to measure the levels of inflammatory factors； an automatic biochemical detector was used to measure liver function parameters； HE staining， Masson staining， Sirius Red staining， and α-SMA immunofluorescence assay were used to evaluate liver fibrosis. Hepatic stellate cells （HSCs） stimulated by TGF-β were co-cultured with hUCMSCs in the medium with or without chitinase-3 like-protein-1 （CHI3L1）， and Western blot was used to measure the expression levels of proteins. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the Dunnett’s t-test was used for further comparison between two groups. ResultsMasson staining and Sirius Red staining showed that the CCl4 group had a significantly higher degree of fibrosis than the control group （both P<0.05）， and the MSC group had significant alleviation of fibrosis compared with the CCl4 group （both P<0.05）. Compared with the control group， the CCl4 group had significant increases in the levels of interleukin-1β， interleukin-6 （IL-6）， aspartate aminotransferase （AST）， alanine aminotransferase （ALT）， and alkaline phosphatase （ALP） （all P<0.05）， and compared with the CCl4 group， the MSC group had significant reductions in the levels of IL-6， AST， ALT， and ALP （all P<0.05）. The CCl4 group had significantly higher expression levels of CHI3L1 and α-SMA than the control group and the MSC group （all P<0.05）. The cell culture experiment showed that the MSC+HSC group had a significantly higher expression level of Bax than the HSC group and the MSC+CHI3L1 group （both P<0.05）， suggesting that CHI3L1 reversed the pro-apoptotic effect of MSC on activated HSCs. ConclusionThis study shows that hUCMSCs can improve liver fibrosis in mice， possibly by inhibiting CHI3L1 to promote the apoptosis of HSCs.

Research progress of YKL-40 protein in ocular diseases / 中国医师杂志

YKL-40 protein, also called chitinase 3 like 1 (CHI3L1), is a highly conserved secreted glycoprotein in racial evolution, belonging to the " 18-glycosyl hydrolase" family. A large number of studies have shown that YKL-40 is involved in the pathological process of many diseases. There is little research information about YKL-40 in ocular diseases yet. This article mainly summarizes the research progress of YKL-40 in ocular diseases in the domestic and foreign literatures to provide reference for further clinical research.

Signal transducer and activator of transcription 6 mediates skeletal muscle cell injury in septic mice by regulating ferroptosis / 中华危重病急救医学

Objective:To explore the effect of signal transducer and activator of transcription 6 (STAT6) on ferroptosis in skeletal muscle cells in sepsis model and its potential mechanism.Methods:Twenty-four 8-week-old male specific pathogen free Kunming mice were divided into normal control group, sham group, sepsis model group and STAT6 inhibitor pretreatment group according to random number table method with 6 mice in each group. A mouse sepsis model was reproduced by cecal ligation and perforation (CLP). In the sham group, the skin of mice was sutured after exposing the cecum tissue. In the STAT6 inhibitor pretreatment group, 10 mg/kg AS1517499 was injected intraperitoneally 1 hour before model reproduction. The sham group and the model group were intraperitoneally injected with the same volume of normal saline. Mice in the normal control group did not receive any operation or drug intervention. The mice were sacrificed 24 hours after model reproduction, and the muscle tissue of hind limb was obtained under sterile condition. Hematoxylin-eosin (HE) staining was used to observe the histopathology with optical microscope, and mitochondrial morphological changes were observed by transmission electron microscopy after double staining with uranium acetate lead citrate. The ferroptosis marker proteins expressions of chitinase-3-like protein 1 (CHI3L1), cyclooxygenase-2 (COX-2), acyl-CoA synthetase long-chain family member 4 (ACSL4), ferritin heavy chain 1 (FTH1), and glutathione peroxidase 4 (GPx4) were detected by Western blotting.Results:Under the optical microscope, the morphology and structure of skeletal muscle tissues in the normal control and sham groups were normal. In the model group, the structure of skeletal muscle tissues was loose, the muscle fiber became smaller and atrophic, inflammatory cell infiltration and even muscle fiber loss were found. Compared with the model group, the structure of skeletal muscle tissues was tight and skeletal muscle atrophy was improved in the STAT6 inhibitor pretreatment group. The ultrastructure of skeletal muscle cell in the normal control and sham groups was normal under transmission electron microscope. The ultrastructure characteristics of skeletal muscle in the model group showed that cell membrane was broken and blister, mitochondria became smaller and membrane density increased, the mitochondrial crista decreased or disappeared, the mitochondrial outer membrane was broken, and the nucleus was normal in size but lacked chromatin condensation. Compared with the model group, the STAT6 inhibitor pretreatment group had a significant improvement in the ultrastructure of muscle cells. Compared with the normal control and sham groups, the protein expressions of CHI3L1, COX-2, ACSL4 and FTH1 in the muscle of the model group were significantly increased, while the protein expression of GPx4 was decreased significantly, indicating that the skeletal muscle cells in the mouse sepsis model showed characteristic mitochondrial injury and abnormal expression of ferroptosis markers. Compared with the model group, the protein expressions of CHI3LI, COX-2, ACSL4 and FTH1 in the STAT6 inhibitor pretreatment group were significantly decreased [CHI3L1 protein (CHI3L1/GAPDH): 0.70±0.08 vs. 0.97±0.09, COX-2 protein (COX-2/GAPDH): 0.61±0.03 vs. 0.83±0.03, ACSL4 protein (ACSL4/GAPDH): 0.75±0.04 vs. 1.02±0.16, FTH1 protein (FTH1/GAPDH): 0.49±0.06 vs. 0.76±0.13, all P < 0.05], while the protein expression of GPx4 was significantly increased (GPx4/GAPDH: 1.14±0.29 vs. 0.53±0.03, P < 0.05). Conclusions:Sepsis can induce ferroptosis in skeletal muscle cells of mice. STAT6 may mediate ferroptosis in mouse skeletal muscle cells by regulating the expressions of COX-2, ACSL4, FTH1 and GPx4, thereby inducing skeletal muscle cell injury in sepsis.

Value of serum chitinase-3-like protein 1 in predicting the risk of decompensation events in patients with liver cirrhosis / 临床肝胆病杂志

Objective To investigate the value of serum chitinase-3-like protein 1 (CHI3L1) in predicting the risk of decompensation events in patients with liver cirrhosis, since prediction of decompensation events and adoption of active preventive measures are the key to improving the survival time of patients with liver cirrhosis. Methods A case-control study was conducted for 305 patients with liver cirrhosis who were diagnosed and treated in Tianjin Second People's Hospital from January 2019 to May 2021, among whom there were 200 patients with compensated liver cirrhosis and 105 patients with decompensated liver cirrhosis at baseline. According to whether decompensation events occurred within 1 year, the 305 patients with liver cirrhosis were divided into decompensation group with 79 patients and non-decompensation group with 226 patients; according to whether decompensation events occurred for the first time within 1 year, the 200 patients with compensated liver cirrhosis were divided into first-time decompensation group with 43 patients and non-first-time decompensation group with 157 patients. The independent samples t -test or the Mann-Whitney U test was used for comparison of normally distributed continuous data between groups, and the Wilcoxon rank-sum test or the chi-square test was used for comparison of categorical data between groups. The binary logistic regression analysis was used to investigate the association between each variable and decompensation events; the receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC) were used to investigate the value of each variable in predicting decompensation events, and the maximum value of Youden index was used to determine the optimal cut-off value. Results The patients who experienced decompensation events within 1 year had a significantly higher baseline serum level of CHI3L1 than those who did not experience such events [243.00 (136.00-372.00) ng/mL vs 117.50 (67.75-205.25) ng/mL, U =4720.500, P < 0.001], and the patients who experienced decompensation events for the first time within 1 year had a significantly higher baseline serum level of CHI3L1 than those who did not experience such events [227.98 (110.00-314.00) ng/mL vs 90.00 (58.00-168.50) ng/mL, U =1 681.500, P < 0.001]. Patients with cirrhosis with higher baseline CHI3L1 levels had an increased risk of decompensation events within 1 year ( OR =1.004, 95% CI : 1.002-1.006, P < 0.001); Patients with compensated cirrhosis with higher baseline serum CHI3L1 levels had an increased risk of first decompensated event within 1 year ( OR =1.006, 95% CI : 1.003-1.008, P < 0.001). The baseline serum level of CHI3L1 had an AUC of 0.751 in predicting the risk of first-time decompensation events, with a sensitivity of 90.7% and a specificity of 55.4% at the optimal cut-off value of 95.5 ng/mL. The predictive model based on the combination of serum CHI3L1 level and Child-Pugh class had an AUC of 0.809, with a sensitivity of 72.1% and a specificity of 77.1% at the maximum value of Youden index. Conclusion Serum CHI3L1 level can be used as an effective predictive factor for the risk of first-time decompensation events in patients with compensated liver cirrhosis, and its combination with Child-Pugh class shows a higher predictive value.

Diagnostic value of novel hepatic fibrosis markers in assessing cirrhosis in patients with chronic hepatitis C / 中华肝脏病杂志

Objective: To investigate the efficacy of chitinase-3-like protein 1 (CHI3L1) and Golgi protein 73 (GP73) in the diagnosis of cirrhosis and the dynamic changes of CHI3L1 and GP73 after HCV clearance in patients with chronic hepatitis C (CHC) treated with direct-acting antiviral drugs (DAAs). The comparison of continuous variables of normal distribution were statistically analyzed by ANOVA and t-test. The comparison of continuous variables of non-normal distribution were statistically analyzed by rank sum test. The categorical variables were statistically analyzed by Fisher's exact test and χ(2) test. Correlation analysis was performed using Spearman correlation analysis. Methods: Data of 105 patients with CHC diagnosed from January 2017 to December 2019 were collected. The receiver operating characteristic curve (ROC curve) was plotted to study the efficacy of serum CHI3L1 and GP73 for the diagnosis of cirrhosis. Friedman test was used to compare CHI3L1 and GP73 change characteristics. Results: The areas under the ROC curve for CHI3L1 and GP73 in the diagnosis of cirrhosis at baseline were 0.939 and 0.839, respectively. Serum levels of CHI3L1 and GP73 in the DAAs group decreased significantly at the end of treatment compared with baseline [123.79 (60.25, 178.80) ng/ml vs. 118.20 (47.68, 151.36) ng/ml, P = 0.001; 105.73 (85.05, 130.69) ng/ml vs. 95.52 (69.52, 118.97) ng/ml, P = 0.001]. Serum CHI3L1 and GP73 in the pegylated interferon combined with ribavirin (PR) group were significantly lower at the end of 24 weeks of treatment than the baseline [89.15 (39.15, 149.74) ng/ml vs. 69.98 (20.52, 71.96) ng/ml, P < 0.05; 85.07 (60.07, 121) ng/ml vs. 54.17 (29.17, 78.65) ng/ml, P < 0.05]. Conclusion: CHI3L1 and GP73 are sensitive serological markers that can be used to monitor the fibrosis prognosis in CHC patients during treatment and after obtaining a sustained virological response. Serum CHI3L1 and GP73 levels in the DAAs group decreased earlier than those in the PR group, and the serum CHI3L1 levels in the untreated group increased compared with the baseline at about two years of follow-up.

Proteins: Neglected active ingredients in edible bird's nest / 中草药·英文版

Edible bird's nest (EBN) is a kind of natural invigorant with a long history of consumption in Asia, especially in China. EBN is formed by mixing the saliva of swiftlets (Aerodramus) with feathers and other components during the breeding season. Proteins are the most important nutrient in EBN. By studying proteins in EBN, we can not only elucidate their components at the molecular level, but also study their bioactivities. Therefore, it is of great significance to study the proteins in EBN. Previous research on the proteins in EBN was preliminary and cursory, and no one has summarized and analyzed the proteins in EBN and correlated the bioactivities of these proteins with the biological functions of EBN. This article focused on the proteins in EBN, listed the proteins identified in different proteomic studies, and introduced the sources, structures and bioactivities of the most frequently identified proteins, including acidic mammalian chitinase, lysyl oxidase homolog 3, mucin-5AC, ovoinhibitor, nucleobindin-2, calcium-binding protein (MW: 4.5 × 104) and glucose-regulated protein (MW: 7.8 × 104). The properties of these proteins are closely related to the bioactivities of EBN. Therefore, this article can provide inspiration for further research on the efficacy of EBN.

Role and mechanisms of CHI3L1 in coronary artery lesions in a mouse model of Kawasaki disease-like vasculitis / 中国当代儿科杂志

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.

Reutilization of waste fungal biomass for concomitant production of proteochitinolytic enzymes and their catalytic products by Alcaligenes faecalis SK10

Fungal biomass, being organic waste, could be an excellent source of protein, carbohydrate and minerals. However, it has not been exploited fully until now. Efficient management of this waste can not only address the environmental impact on its disposal but also yield value-added metabolites. In the present study, in order to explore its potential, we subjected dead fungal biomass of Aspergillus niger SKN1 as substrate for both fermentative and enzymatic biodegradation, respectively by potent proteo-chitinolytic bacteria Alcaligenes faecalis SK10 and its enzyme cocktail. The results revealed that reasonable amount of protease and chitinase could be biosynthesized by the fermentative mode of utilization, while a mixture of amino acid, peptides and low-molecular weight amino-sugar (mono and oligomeric form of N-acetylglucosamine) could be generated through enzymatic hydrolysis. The physicochemical condition of both the bioprocess was subsequently optimized through statistical approach. The projected utilization of waste zero-valued fungal biomass offer a sustainable and environmentally sound method for production of microbial metabolites and large scale execution of the same could be proficient and in tune with the principle of circular economy.

An investigation into clinical significance of serum chitinase 3-like protein 1 in pemphigus vulgaris / 中华皮肤科杂志

Objective:To detect the serum level of chitinase-3-like protein 1 (YKL-40) in patients with pemphigus vulgaris, and to analyze its correlation with the severity of pemphigus vulgaris.Methods:From January 2017 to May 2018, serum samples were collected from 38 patients with pemphigus vulgaris in Department of Dermatology, the Affiliated Hospital of Southwest Medical University, and those collected from 14 age-, gender- and body mass index-matched healthy volunteers served as controls. Serum levels of YKL-40 and Th1/Th2/Th17-related cytokines were detected by using Luminex ? 200 TM system. Mann-Whitney U test was used to compare serum levels of cytokines between the patient group and control group; binary logistic regression was used to investigate factors independently related to the severity of pemphigus vulgaris; a receiver operating characteristic (ROC) curve was drawn, and the area under the curve, sensitivity and specificity were calculated to evaluate the ability of YKL-40 to predict the severity of pemphigus vulgaris. Results:Compared with the control group, the patient group showed significantly increased serum levels of YKL-40 (expressed as median[ Q1, Q3]: 15.22 [14.19, 15.93] vs. 13.64 [13.21, 14.63]μg/L, z=-3.88, P < 0.05) , interleukin (IL) -6 (2.05 [1.49, 4.21] vs. 1.57[1.38, 1.75]ng/L, z=-2.44, P < 0.05) , IL-7 (7.45[5.63, 11.63] vs. 3.77[2.21, 5.97]ng/L, z=-3.26, P < 0.05], IL-8 (6.59[3.60, 14.73] vs. 4.36[2.96, 6.53]ng/L, z=-1.96, P < 0.05) , IL-2R-α (509.08 [386.36, 757.67] vs. 336.44[309.86, 458.71]ng/L, z=-2.35, P < 0.05) , and C5a (100.35 [78.31, 140.84] vs. 72.08 [37.23, 82.08] ng/L, z = -3.04, P < 0.05) . The concentration of serum YKL-40 gradually decreased along with the reduction of lesion areas ( r = 0.63, P < 0.001) , and YKL-40 was independently correlated with the severity of pemphigus vulgaris ( P = 0.025, OR = 46.54, 95% CI: 1.61, 1 347.19) . The area under the curve of YKL-40 was 0.783 (95% CI: 0.613, 0.953) for distinguishing between patients with severe to extremely severe pemphigus vulgaris and those with mild to moderate pemphigus vulgaris. Conclusion:The serum level of YKL-40 is strongly correlated with the severity of pemphigus vulgaris, and has a potential value in predicting the severity of this disease.

Chitinase-3-like protein 1 plays a role in lumbar facet joint degeneration / 中华骨科杂志

Objective:To investigate the effect of CHI3L1 on the biological function of chondrocytes and its role in lumbar facet joint degeneration.Methods:The human lumbar facet joint articular cartilage were collected, and the relative mRNA expression of CHI3L1 gene detected by quantitative fluorescence PCR. Then explored the correlation between joint degeneration and gender, age and relative mRNA expression of CHI3L1. Human chondrocytes were cultured in vitro. The effects of CHI3L1 on chondrocyte proliferation, cycling, and apoptosis, as well as expression of related inflammatory factors, were investigated. The mechanism by which CHI3L1 regulates the degeneration of articular cartilage was investigated using the signal transduction pathway protein chip.Results:There was a positive correlation between the grade of degeneration in lumbar facet joint and the relative expression of CHI3L1 gene mRNA ( r=0.76, P<0.001). There was no correlation with the patient's gender ( r=-0.12, P=0.500). A positive correlation between the age of patients and the relative expression of CHI3L1 gene mRNA was found ( r=0.47, P=0.005). Compared with the non-degenerative group, the expression of CHI3L1 gene mRNA significantly increased in the degenerative group, and the expression of CHI3L1 gradually increased with the aggravation in the grade of degeneration ( F=18.90, P<0.001). Compared with the non-degenerative group, the chondrocytes in the CHI3L1 group had significantly lower proliferation at 48 h (OD 490/fold=7.132), 72 h (OD 490/fold=4.803), 96 h (OD 490/fold=2.431) and 120 h (OD 490/fold=0.009). The ratio of chondrocytes in G1 phase, S phase and G2/M phase were 85.03%±3.05%, 12.78%±2.29% and 0.90%±0.76% in the CHI3L1 group, and 73.93%±2.73%, 22.81%±1.93% and 0.99%±0.87% in control group, respectively. There were significant differences in the percentage of chondrocytes in G1 phase ( t=4.70, P<0.001) and S phase ( t=5.80, P<0.001) between the two groups. The percentages of apoptosis in chondrocyte in CHI3L1 group and control group were 8.64%±0.76% and 5.68%±1.13%, which has a statistically difference ( t=4.47, P<0.001). The expression of IL-6 in chondrocytes of CHI3L1 group was 49.60±0.01 pg/ml, which was higher than that of 47.88±0.01 pg/ml in the control group ( t=132.70, P<0.001). The expression of TNF-α was 95.93±0.02 pg/ml, which was higher than 90.69±0.02 pg/ml in the control group ( t=376.10, P<0.001). There was significant difference in expression of IL-6 in chondrocytes between the CHI3L1 group and the control group ( t=132.72, P<0.001). The expression of TNF-α ( t=376.10, P<0.001) was statistically difference. Protein chip detected 53 proteins with significant differences in expression and 43 proteins with significant differences in protein phosphorylation levels. Bioinformatics analysis was used to identify 16 signaling pathways in which the above different proteins might be involved, including ErbB, PI3K, Akt, Ras, JAK, STAT3, MAPK pathway. In the MAPK pathway, the expression of MAPK1 and RAF1 proteins was higher in the chondrocytes of the CHI3L1 group than in the control group (1.094±0.00 vs. 0.814±0.00, 0.988±0.00 vs. 0.786±0.00; t=103.16, P<0.001; t=54.32, P<0.001). Compared with the control group, the expression of MAPK1 and RAF1 proteins was significantly increased in the chondrocytes of the CHI3L1 group. Conclusion:The expression of CHI3L1 is corrected to articular cartilage degeneration. CHI3L1 is able to inhibit the proliferation of articular chondrocytes, which regulated the cycling of chondrocytes from G1 phase to S phase, promote the apoptosis of chondrocytes, and promote the expression of IL-6 and TNF-α in chondrocytes. Regulation of chondrocytes biological function through the MAPK pathway, which is a potential biomarker for the clinical diagnosis and treatment of lumbar joint degeneration.

YKL-40 at admission predicts stroke-associated pneumonia and outcome in patients with acute ischemic stroke / 国际脑血管病杂志

Objective:To investigate the predictive value of YKL-40 at admission on stroke-associated pneumonia (SAP) and poor outcome in patients with acute ischemic stroke (AIS).Methods:Patients with AIS admitted to Taixing People’s Hospital from February 2020 to March 2021 were enrolled prospectively. The poor outcome was defined as 3-6 points on the modified Rankin Scale at 90 d after onset. Multivariate logistic regression analysis was used to determine the independent predictors of SAP and poor outcome, and the predictive value of serum YKL-40 on SAP and poor outcome was evaluated by receiver operating characteristic (ROC) curve. Results:A total of 377 patients with AIS were enrolled. The median serum YKL-40 was 127.16 μg/L. One hundred and four patients (27.6%) had SAP, and 126 (33.4%) had poor outcomes at 90 d after onset. Multivariate logistic regression analysis showed that after adjusting for confounding factors, YKL-40 was the independent predictors of SAP (odds ratio [ OR] 1.005, 95% confidence interval [ CI] 1.003-1.008; P=0.001) and poor outcome at 90 d ( OR 1.009, 95% CI 1.006-1.011; P=0.001). The ROC curve analysis showed that the area under the curve of YKL-40 for predicting SAP was 0.769 (95% CI 0.713-0.824; P<0.001), the best cutoff value was 168.70 μg/L, and the sensitivity and specificity were 71.2% and 75.1% respectively; the area under the curve of YKL-40 for predicting poor outcome at 90 d was 0.787 (95% CI 0.735-0.840; P<0.001), the best cutoff value was 195.56 μg/L, and the sensitivity and specificity were 68.3% and 84.1% respectively. Conclusion:Higher serum YKL-40 at admission has a good predictive value for SAP and poor outcome at 90 d in patients with AIS.

Serum YKL-40 levels in patients with multiple sclerosis / Níveis séricos de YKL-40 em pacientes com esclerose múltipla

ABSTRACT Background: Multiple sclerosis (MS) is a chronic inflammatory disease affecting the central nervous system. The YKL-40 protein, which is secreted from various cells that contribute to inflammation and infection, plays a role in immune regulation. Objective: This study investigated the serum YKL-40 levels of patients with clinically isolated syndrome (CIS) and MS. Methods: The participants was divided into three groups: 1) patients with CIS (n = 20); 2) patients with relapsing-remitting MS (RRMS; n = 39); and 3) healthy individuals (n = 35). The YKL-40 levels in serum samples obtained from the participants were measured using enzyme-linked immunoassays. Results: The median serum YKL-40 level was 20.2 ng/mL (range 9.8-75.9 ng/mL) in the patients with CIS, 22.7 ng/mL (range 13.4-57.9 ng/mL) in the patients with RRMS and 11.0 ng/mL (range 10.0-17.3 ng/mL) in the control group (p < 0.001). The serum YKL-40 levels in the patients with RRMS were correlated with the patients' expanded disability status scale scores and ages (p < 0.05). No relationships were determined between the serum YKL-40 levels and the other variables (p > 0.05). The serum YKL-40 levels were higher in the CIS group than in the MS group. These findings show that the serum YKL-40 levels were high even at the beginning of the disease. The serum YKL-40 levels were also not involved in the progression to clinically definite MS. Conclusions: The findings from this study suggested that YKL-40 may be a useful marker for the inflammatory process of MS.

RESUMO Contexto: A Esclerose Múltipla (EM) é uma doença inflamatória crônica que afeta o sistema nervoso central. A proteína UKL-40, secretada de várias células que participam de processos inflamatórios e infecciosos, desempenha um importante papel na regulação imunológica. Objetivo: Este estudo investigou níveis séricos de YKL-40 em pacientes com Síndrome Clinicamente Isolada (SCI) e EM. Métodos: Os participantes foram divididos em três grupos: 1) pacientes com SCI (n = 20); 2) pacientes com EM recorrente-remitente (EMRR; n = 39); e 3) indivíduos saudáveis (n = 35). Os níveis de YKL-40 em amostras séricas obtidas dos participantes foram medidos usando-se imunoensaios ligados a enzimas. Resultados: O nível sérico médio de YKL-40 foi 20.2 ng/mL (range 9.8-75.9 ng/mL) em pacientes com CIS, 22.7 ng/mL (intervalo entre 13.4-57.9 ng/mL) em pacientes com EMRR e 11.0 ng/mL (intervalo entre 10.0-17.3 ng/mL) no grupo controle (p < 0.001). Os níveis séricos de YKL-40 em pacientes com EMRR estavam correlacionados às pontuações e idades dos pacientes na EDSS (p < 0.05). Não foram determinadas relações entre os níveis séricos de YKL-40 e outras variáveis (p > 0.05). Os níveis séricos de YKL-40 no grupo SCI estavam mais elevados do que no grupo EM. Estes resultados demonstram que os níveis séricos de YKL-40 estavam mais elevados até mesmo no início da doença. Os níveis séricos de YKL-40 também não estavam associados à progressão da EM clinicamente definida. Conclusões: A partir deste estudo, os resultados sugeriram que a proteína YKL-40 pode ser um indicador útil no processo inflamatório da EM.

Effects of chitinase-3-like protein 1 on the expression of inflammatory damage-related molecules in mouse skeletal muscle satellite cells induced by lipopolysaccharide / 中华危重病急救医学

Objective:To explore the potential mechanism of chitinase-3-like protein 1 (CHI3L1) involved in skeletal muscle stem cell injury induced by sepsis.Methods:Six different concentrations of lipopolysaccharide (LPS) were used to stimulate mouse skeletal muscle satellite cells cultured in vitro. Enzyme linked immunosorbent assay (ELISA) and cell counting kit-8 (CCK-8) were used to determine the optimal concentration. The overexpression and interference vectors of CHI3L1 were constructed to transfect skeletal muscle satellite cells, and the transfection efficiency was verified by polymerase chain reaction (PCR) and Western blotting. The cells were randomly divided into blank control group (cells without any intervention), model group (LPS-stimulated untransfected cells), overexpressing CHI3L1 group (LPS-stimulated cells transfected with CHI3L1 plasmid), overexpressing CHI3L1 control group [LPS-stimulated cells transfected with negative control (NC) plasmid], CHI3L1 interference group [LPS-stimulated cells transfected with CHI3L1 small interfering RNA (siRNA)], CHI3L1 interference control group (LPS-stimulated cells transfected with CHI3L1-siRNA NC). The levels of extracellular caspase-1 and interleukin-1β (IL-1β) were detected by ELISA. The protein expressions of intracellular IL-1β, signal transducer and activator of transcription 3 (STAT3), protein kinase B (Akt) and phosphorylated Akt (p-Akt) were detected by Western blotting. Results:According to the results of CCK-8 and ELISA, the best concentration of 5 mg/L LPS was selected for the subsequent experiment. The transfection was validated by PCR and Western blotting. Compared with the blank control group, the levels of extracellular IL-1β, caspase-1 and the protein expressions of intracellular Akt, p-Akt, and IL-1β were significantly increased in the model group [IL-1β (ng/L): 11.22±0.55 vs. 8.63±0.63, caspase-1 (pmol/L): 9.47±0.22 vs. 8.65±0.15, Akt/GAPDH: 1.36±0.12 vs. 1.06±0.15, p-Akt/GAPDH: 0.78±0.07 vs. 0.09±0.01, IL-1β/GAPDH: 1.38±0.12 vs. 0.18±0.03, all P < 0.05]. Compared with the model group and the overexpressing CHI3L1 control group, the levels of extracellular IL-1β, caspase-1 and the protein expressions of intracellular p-Akt and IL-1β were significantly increased in the overexpressing CHI3L1 group [IL-1β(ng/L): 14.93±0.97 vs. 11.22±0.55, 9.38±0.40, caspase-1 (pmol/L): 10.35±0.03 vs. 9.47±0.22, 8.46±0.24, p-Akt/GAPDH: 1.21±0.04 vs. 0.78±0.07, 0.63±0.04, IL-1β/GAPDH: 1.87±0.08 vs. 1.38±0.12, 1.51±0.17, all P < 0.05]. Compared with the model group and the CHI3L1 interference control group, the levels of extracellular IL-1β, caspase-1 and the protein expressions of intracellular p-Akt and IL-1β were significantly decreased in the CHI3L1 interference group [IL-1β(ng/L): 8.98±0.73 vs. 11.22±0.55, 10.44±0.65, caspase-1 (pmol/L): 7.61±0.63 vs. 9.47±0.22, 8.37±0.38, p-Akt/GAPDH: 0.50±0.04 vs. 0.78±0.07, 0.94±0.06, IL-1β/GAPDH: 0.77±0.02 vs. 1.38±0.12, 1.13±0.07, all P < 0.05]. Conclusions:CHI3L1 may mediate the damage of skeletal muscle stem cells in sepsis by increasing the expression of caspase-1 and IL-1β. CHI3L1 may be involved in the regulation of Akt signaling pathway in skeletal muscle stem cells, but has no significant effect on STAT3 signaling pathway.

The value of acidic mammalian chitinase in early diagnosis of occupational pneumoconiosis / 中国职业医学

OBJECTIVE: To observe the expression of acidic mammalian chitinase(AMCase) in lung tissue of silicosis model rats, and bronchoalveolar lavage fluid(BALF) and serum of patients with occupational pneumoconiosis, and to evaluate the value of AMCase in the early diagnosis of pneumoconiosis. METHODS: i) The specific pathogen free adult male Wistar rats were randomly divided into control group and model group, with 15 rats in each group. The rats in the silicosis model group was exposed to free silica dust with a concentration of 2 000.0 mg/m~3 by dynamic inhalation for three hours a day, while the rats in control group were not exposed to dust. Five rats in the two groups were sacrificed at 4, 12 and 24 weeks after dust exposure. ii) By random number table method, a total of 191 patients with occupational pneumoconiosis who received large capacity lung lavage were selected as the pneumoconiosis group, 12 dust-exposed workers who received large capacity lung lavage were selected as the dust control group, and 200 healthy coal miners exposed to dust were selected as healthy control group. iii) Western blotting was used to detect the relative protein expression of AMCase, type Ⅰ collagen(COLⅠ), α-smooth muscle actin(α-SMA) in lung tissues of the rats and the relative protein expression of AMCase in human BALF. Enzyme linked immunosorbent assay was used to detect the level of AMCase protein in human serum. Receiver operating characteristic(ROC) curve was used to evaluate the value of AMCase protein level in human serum for early diagnosis of pneumoconiosis. RESULTS: The relative expression of AMCase, COLⅠand α-SMA protein in lung tissue of rats in the silicosis model group were higher than that of control group(all P<0.01). The relative expression of AMCase protein in BALF of pneumoconiosis group and pneumoconiosis stage Ⅰ, Ⅱ and Ⅲ subgroups were higher than that of dust control group(all P<0.05). The level of AMCase protein in serum of pneumoconiosis group and pneumoconiosis stage Ⅰ, Ⅱ and Ⅲ subgroups were higher than that of healthy control group(all P<0.05). The results of ROC curve analysis showed that the area under ROC curve was 0.78(95% confidence interval: 0.74-0.82).When the cut-off value of serum AMCase protein level was 466.0 ng/L, the sensitivity was 73.8%, and the specificity was 72.6%. CONCLUSION: AMCase protein in human serum has value for early diagnosis of pneumoconiosis and it could be a potential biomarker for early diagnosis of pneumoconiosis.

High YKL-40 serum levels and its expression in the muscle tissues of patients with antisynthetase syndrome

Abstract Background: The protein chitinase-3-like-1 (YKL-40) is rarely analyzed in patients with myositis. Therefore, we aimed to evaluate YKL-40 serum levels; correlate them with laboratory and clinical parameters, disease status, and treatment schemes; and analyze the YKL-40 expression in the muscle tissues of patients with antisynthetase syndrome (ASSD). Methods: This cross-sectional single-center study included 64 adult patients with ASSD who were age-, gender-, and ethnicity-matched to 64 healthy control individuals. Their YKL-40 serum levels were analyzed using the Enzyme-Linked Immunosorbent Assay (ELISA) kit method, while YKL-40 expression in muscle tissues was analyzed using an immunohistochemical technique. Disease status was assessed using the International Myositis Assessment and Clinical Studies Group (IMACS) set scores. Results: The patients' mean age was 44.8 ± 11.8 years, and median disease duration was 1.5 (0.0-4.0) years. These patients were predominantly female (82.8%) and Caucasian (73.4%). Most patients had stable disease. The median YKL-40 serum level was significantly higher in patients with ASSD when compared to the healthy individuals: 538.4 (363.4-853.1) pg/mL versus 270.0 (201.8-451.9) pg/mL, respectively; P < 0.001. However, YKL-40 serum levels did not correlate with any clinical, laboratory, disease status, or therapeutic parameters (P > 0.050), except tumor necrosis factor alpha (TNF-α) serum levels (Spearman's correlation, rho = 0.382; P = 0.007). YKL-40 was highly expressed by inflammatory cells found in muscle biopsy specimens. Conclusions: High YKL-40 serum levels were observed in patients with ASSD and correlated positively with TNF-α serum levels. Moreover, YKL-40 was expressed by the inflammatory cells of the muscle tissue.

Antagonism of plant growth promoting rhizobacteria against the causal agent of the vascular wilting of tomato / Antagonismo de rizobacterias promotoras del crecimiento vegetal contra el agente causal de la marchitez vascular del tomate

ABSTRACT Use of biotechnological potential of native microorganisms as bio-inputs is having a great impact on agricultural systems. Plant Growth Promoting Rhizobacteria (PGPR), in addition to their beneficial effect on plant growth and on the availability of soil elements, also have an antagonistic effect against different pathogens. In this study, growth promotion mechanisms with emphasis on the antagonism of PGPR isolated from sugarcane and tomato crops were evaluated. Antagonism against Fusarium oxysporum f.sp lycopersici (Fol) was determined by dual tests, inhibition of germination and production of chitinases and endoglucanases. 52 isolates were evaluated and according to their results in dual tests 10 were selected for further analysis. Isolate GIBI127 showed the best percentage of Inhibition Germination (IG) of Fol (59.29%). Then, a selection index was calculated using results from gi, dual tests and growth promotion mechanisms to select five best isolates. Finally, these bacteria were evaluated for chitinases and endoglucanases production using Miller's method. As a result, strain GIBI419 (Burkholderia cepacia) showed a higher production of these enzymes. Selected isolates have antagonistic potential along with plant growth promotion characteristics, which can be used for the development of microbial inoculants which allow the establishment of agricultural systems for tomato cultivation that are sustainable, efficient, and environmentally friendly.

RESUMEN El uso del potencial biotecnológico de microorganismos nativos como bioinsumos está teniendo un gran impacto en los sistemas agrícolas. Las rizobacterias promotoras del crecimiento vegetal (PGPR), además de su efecto benéfico en el crecimiento de las plantas y de facilitar la disponibilidad de elementos del suelo, también tienen un efecto antagónico frente a diferentes patógenos. En este estudio se evaluaron mecanismos de promoción del crecimiento con énfasis en el antagonismo de bacterias PGPR aisladas de cultivos de caña de azúcar y tomate. El antagonismo contra Fusarium oxysporum f.sp lycopersici (Fol) se determinó mediante pruebas duales, inhibición de la germinación y producción de quitinasas y endoglucanasas. Se evaluaron 52 aislamientos y según sus resultados en pruebas duales se seleccionaron 10 para su posterior análisis. El aislado GIBI127 mostró el mejor porcentaje de Inhibición de la Germinación (IG) de Fol (59,29%). Luego, se calculó un índice de selección utilizando los resultados de IG, pruebas duales y mecanismos de promoción del crecimiento para seleccionar los cinco mejores aislamientos. Finalmente, estas bacterias fueron evaluadas en la producción de quitinasas y endoglucanasas utilizando el método de Miller. Como resultado, se evidenció la cepa GIBI419 (Burkholderia cepacia) como la de mayor producción de estas enzimas. Los aislados seleccionados tienen un potencial antagónico junto con características de promoción del crecimiento de las plantas, que pueden usarse para el desarrollo de inoculantes microbianos que permitan el establecimiento de sistemas agrícolas para el cultivo de tomate que sean sostenibles, eficientes y amigables con el medio ambiente.

Factors affecting the chitinase activity of Trichoderma asperellum isolated from agriculture field soils

In the present study, 20 fungal strains were isolated from tomato rhizosphere of Senegal. Of 20 strains, five showedthe chitinolytic activity on chitin agar medium. Of the five strains, NG4 showed the maximum solubilization zone.This strain was identified by preliminary biochemical and 18S rRNA sequencing analysis. Enzyme productionstarted after 3 days of incubation and maximum was observed after 5 days of incubation. Culture filtrate amendedwith 0.1% colloidal chitin was used in the production medium. The optimum conditions for maximum chitinaseactivity are – 6 days of growth and temperature of 30°C at pH 6.0. The chitinase activity was also influenced by theaddition of carbon and nitrogen sources in the production medium.

Effect of CHI3L1 on the oxidative stress of human umbilical vein endothelial cells treated with palmitic acid / 解放军医学杂志

Objective To observe the effect of chitinase-3-like protein 1 (CHI3L1) on the oxidative stress of human umbilical vein endothelial cells (HUVECs) after treatment with palmitic acid, and preliminarily explore the molecular mechanism. Methods HUVECs were cultured in vitro, treated with different concentrations of CHI3L1 for 24 hours, and the MTT assay was used to determine the proliferation of HUVECs. The cells were divided into the control group (untreated group), palmitic acid group and CHI3L1+palmitic acid group. Cells in palmitic acid group were treated with 100 μmol/L palmitic acid for 24 hours, and in CHI3L1+palmitic acid group were pretreated with 100 ng/ml CHI3L1 for 2 hours, then 100 μmol/L palmitic acid were added and co-treating for 24 hours. Western blotting was used to detect the contents of nuclear and cytoplasmic p65, nuclear Lamin B, Actin, heme oxygenase (HMOX), reduced coenzyme /Ⅱ dependent quinone oxidoreductase (NQO1), phosphorylated protein kinase B (p-Akt), endoplasmic reticulum redox 1-like protein (Ero1-Lα), Calnexin, protein disulfide isomerase (PDI), chaperonin/ glucose regulatory protein (Bip1/Grp) 78, endoplasmic reticulum nuclear signal transduction protein (IRE)-1α and phosphorylated eukaryotic translation initiation factor (p-eIF) 2α. The contents of IL-6 and TNF-α were measured by ELISA, the activity of NF-κB was measured by DNA binding assay, and the nuclear translocation of Nrf2 was detected by immunofluorescence. Results MTT results showed that compared with the control, treatment with 100 ng/ml CHI3L1 for 24 hours did not decrease the activity of HUVECs (94.17±6.13 vs. 100.00±0.00). Western blotting results showed that the p65 level in nucleus of CHI3L1+palmitic acid group was lower than that in palmitic acid group (0.77±0.04 vs. 0.92±0.09, P<0.05), but in cytoplasm was higher than that in palmitic acid group (0.45±0.04 vs. 0.27±0.05, P<0.05). The DNA binding activity of NF-κB in CHI3L1+palmitic acid group was lower than that in palmitic acid group (0.26±0.04 vs. 0.43±0.07, P<0.05). ELISA results showed that the contents of TNF-α and IL-6 were lower in CHI3L1+palmitic acid group than those in palmitic acid group [(85.91±21.16) pg/ml vs. (221.12±18.71) pg/ml; (71.43±10.56) pg/ml vs. (95.03±11.2) pg/ml, P<0.05]. Western blotting results showed that the levels of HMOX and NQO1 were significantly higher in CHI3L1+palmitic acid group than those in palmitic acid group (0.58±0.07 vs. 0.32±0.09; 1.08±0.04 vs. 0.62±0.09, P<0.05). Immunofluorescence results showed that compared with palmitic acid group, the content of Nrf2 increased significantly in CHI3L1+palmitic acid group (10.26%±4.53% vs. 78.64%±3.16%, P<0.05). Western blotting results showed that the phosphorylation level of PI3K/Akt was significantly higher in CHI3L1+palmitic acid group than those in palmitic acid group (0.51±0.04 vs. 0.15±0.09, P<0.05), and the expression levels of Ero1-Lα, Calnexin, PDI, BIP1/GRP78, IRE-1α and p-eIF2α in endoplasmic reticulum were significantly reduced in CHI3L1+palmitic acid group than those in palmitic acid group (0.32±0.02 vs. 0.39±0.09; 0.42±0.04 vs. 0.54±0.07; 0.19±0.02 vs. 0.24±0.05; 0.11±0.01 vs. 0.17±0.03; 0.19±0.03 vs. 0.33±0.04; and 0.22±0.07 vs. 0.67±0.09. P<0.05). Conclusion CHI3L1 can inhibit the cytokine secretion of HUVECs treated with palmitic acid, and reduce the stress level of endoplasmic reticulum.

Mechanism of ykl-40 regulating apoptosis of rabbit osteoarthritis chondrocytes via pi3k/akt signaling pathway / 中国组织工程研究

BACKGROUND: Due to the close relationship between the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway and the physiological metabolism of bone tissue, human chitinase protein 40 (YKL-40) can regulate the PI3K/Akt signaling pathway related to breast cancer pathogenesis. Therefore, it is speculated that YKL-40 may regulate apoptosis in knee osteoarthritis (KOA) chondrocytes through the PI3K/Akt signaling pathway. OBJECTIVE: To study the mechanism by which YKL-40 regulates apoptosis in rabbit KOA chondrocyte s through the PI3K/Akt signaling pathway. METHODS: (1) New Zealand white rabbits were randomized into two groups. An animal model of KOA was made using anterior cruciate ligament dissection in the model group, whereas the right posterior knee joint capsule was cut but not dissected in the control group. Chondrocytes were extracted from the rabbits at 6 weeks after modeling. Hematoxylin-eosin staining and Mankin histological scoring of the cartilage tissue were performed, whereas immunohistochemical staining was used to detect type II collagen expression in chondrocytes. (2) The second-generation chondrocytes in the control group were used as normal control group, and those in the model group were further divided into four groups, followed by culture with high glucose DMEM medium containing 10% fetal bovine serum in KOA model group, 100 μg/L YKL-40 in KOA + YKL group, 50 µmol/L LY294002 in KOA + LY group, and 50 µmol/L LY294002 + 100 μg/L YKL-40 in KOA + YKL + LY group. The expression levels of collagen type II, matrix metalloproteinase 13, Akt, p-Akt, P53, Bcl-2 proteins in chondrocytes were detected by western blot. RESULTS AND CONCLUSION: Hematoxylin-eosin staining, Mankin histological score, and collagen type II immunohistochemical staining confirmed the successful construction of KOA animal model and successful chondrocyte culture. Compared with the normal control group, the collagen type II, Bcl-2, p-Akt protein expression levels in chondrocytes were significantly reduced in the KOA model group (P 0.05). However, there were significant differences between the KOA + YKL group and the KOA + LY group (P 0.05). To conclude, YKL-40 can inhibit the apoptosis of KOA chondrocytes, accelerate the repair of KOA cartilage damage and delay the degeneration of cartilage by activating the PI3K/Akt signaling pathway. Therefore, YKL-40 can be used as a new target for clinical treatment of KOA.

Overexpression of Chitinase A Gene from Serratia marcescens in Bacillus subtilis and Characterization of Enhanced Chitinolytic Activity

Abstract Chitinase enzymes possess various usages in agriculture, biotechnology and medicine due to their chitin degrading property. Thus, efficient production of chitinase enzymes with desired properties has importance for its use. In this study, chitinase A (chiA) gene from Serratia marcescens Bn10 was cloned and heterologously overexpressed using pHT43 vector in Bacillus subtilis 168. The recombinant chitinase was characterized in terms of temperature, pH, and various effectors. The extracellular chitinase activity in recombinant B. subtilis was found 2.15-fold higher than the parental strain after 2 h of IPTG induction. Optimum temperature and pH for the extracellular chitinase activity in the recombinant B. subtilis were determined as 60 oC and pH 9.0, respectively. NaCl, Ca2+, Mn2+, Cu2+, Zn2+, sodium dodecyl sulfate (SDS), Tween-20, and ethanol increased the chitinase activity whereas Mg2+ caused an inhibition. The most notable increment on the chitinase activity was provided by Zn2+ (3.2 folds) and then by SDS (2.9 folds). The chitinase, overproduced by the recombinant B. subtilis 168 heterologously expressing chiA, was determined to have optimum activity at high temperature and alkaline conditions as well as various effectors increase its activity. The extracellular chitinase of recombinant B. subtilis might be a promising source for agricultural, biotechnological and medical applications.