C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway as a therapeutic target and regulatory mechanism for spinal cord injury

Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory damage.The expression of the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis exhibits significant differences before and after injury.Recent studies have revealed that the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis is closely associated with secondary inflammatory responses and the recruitment of immune cells following spinal cord injury,suggesting that this axis is a novel target and regulatory control point for treatment.This review comprehensively examines the therapeutic strategies targeting the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis,along with the regenerative and repair mechanisms linking the axis to spinal cord injury.Additionally,we summarize the upstream and downstream inflammatory signaling pathways associated with spinal cord injury and the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis.This review primarily elaborates on therapeutic strategies that target the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the latest progress of research on antagonistic drugs,along with the approaches used to exploit new therapeutic targets within the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the development of targeted drugs.Nevertheless,there are presently no clinical studies relating to spinal cord injury that are focusing on the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis.This review aims to provide new ideas and therapeutic strategies for the future treatment of spinal cord injury.

C–C motif chemokine ligand 16 inhibits the progression of liver cirrhosis via inactivating hepatic stellate cells

Background:Liver cirrhosis results from many forms of chronic damage,characterized by accumulation of extracellular matrix.The present study aimed to explore a potential non-invasive biomarker and its mechanism in the progression of liver cirrhosis.Methods:Gene Expression Omnibus(GEO)dataset(GSE15654,n=216)was analyzed to screen genes associated with progression of liver cirrhosis.A total of 181 plasma samples,including healthy control(HC,n=20),chronic hepatitis B(CHB,n=77)and HBV-related liver cirrhosis(LC,n=84),were enrolled for validation.In vitro and in vivo experiments were employed for the mechanistic investigation.Results:GEO dataset analysis showed that relatively low mRNA-expression of C–C motif chemokine ligand 16(CCL16)was associated with elevated Child-Pugh score(P=0.034)and worse prognosis(P=0.025).Plasma CCL16 level decreased in a stepwise pattern,with a median concentration of 10.29,6.57 and 4.47 ng/mL in the HC,CHB and LC groups,respectively(P<0.001).Low plasma CCL16 was significantly related to hepatic dysfunction both in the CHB and LC groups(P<0.05).Combination of CCL16 and ALT showed improved distinguishing capability for LC compared to either alone.In vitro,CCL16 expression was downregulated by lipopolysaccharide and hypoxia.Overexpression of CCL16 from human normal liver cell line(LO2)reduced the extracellular matrix associated proteins(Col1 and Col4)in human hepatic stellate cell line(LX-2).In vivo,the pathological feature of cirrhosis was alleviated by the hepatocytespecific expression of CCL16.Conclusions:CCL16 could be a feasible plasma marker to predict the occurrence and progression of liver cirrhosis.CCL16 might impact liver cirrhosis through inactivating hepatic stellate cells.

Macrophage migration inhibitory factor facilitates astrocytic production of the CCL2 chemokine following spinal cord injury

Spinal cord injury causes accumulation of a large number of leukocytes at the lesion site where they contribute to excessive inflammation.Overproduced chemokines are responsible for the migratory process of the leukocytes,but the regulatory mechanism underlying the production of chemokines from resident cells of the spinal cord has not been fully elucidated.We examined the protein levels of macrophage migration inhibitory factor and chemokine C-C motif chemokine ligand 2 in a spinal cord contusion model at different time points following spinal cord injury.The elevation of macrophage migration inhibitory factor at the lesion site coincided with the increase of chemokine C-C motif chemokine ligand 2 abundance in astrocytes.Stimulation of primary cultured astrocytes with different concentrations of macrophage migration inhibitory factor recombinant protein induced chemokine C-C motif chemokine ligand 2 production from the cells,and the macrophage migration inhibitory factor inhibitor 4-iodo-6-phenylpyrimidine attenuated the stimulatory effect.Further investigation into the underlying mechanism on macrophage migration inhibitory factor-mediated astrocytic production of chemokine C-C motif chemokine ligand 2 revealed that macrophage migration inhibitory factor activated intracellular JNK signaling through binding with CD74 receptor.Administration of the macrophage migration inhibitory factor inhibitor 4-iodo-6-phenylpyrimidine following spinal cord injury resulted in the reduction of chemokine C-C motif chemokine ligand 2-recruited microglia/macrophages at the lesion site and remarkably improved the hindlimb locomotor function of rats.Our results have provided insights into the functions of astrocyte-activated chemokines in the recruitment of leukocytes and may be beneficial to develop interventions targeting chemokine C-C motif chemokine ligand 2 for neuroinflammation after spinal cord injury.

血清miR-31、miR-155和CCL26在溃疡性结肠炎中预后不良的诊断价值

目的观察血清miR-31、miR-155和趋化因子配体26(CCL26)在溃疡性结肠炎中预后不良的诊断价值。方法选择2019年1月—2020年6月在我院收治的溃疡性结肠炎的患者119例,根据Mayo评分将其分为活动期组(65例)和缓解期组(54例);同时根据Mayo评分将活动期组分为轻度亚组(25例),中度亚组(22例)和重度亚组(18例);另选择同期在我院健康体检者45例为对照组。比较各组血清miR-31、miR-155和CCL26水平的变化;分析血清miR-31、miR-155和CCL26水平与溃疡性结肠炎严重程度的关系及影响溃疡性结肠炎预后不良的单因素和多因素分析;评估血清miR-31、miR-155和CCL26水平在2年内溃疡性结肠炎发生预后不良的诊断价值。结果溃疡性结肠炎活动期组血清miR-31、miR-155和CCL26水平明显高于缓解期组和对照组(P<0.05),而缓解期组明显高于对照组(P<0.05)。血清miR-31、miR-155和CCL26水平随着溃疡性结肠炎严重程度的增加而升高(P<0.05)。单因素和多因素分析发现UCEIS评分>6分,血清miR-31、miR-155和CCL26水平升高是发生溃疡性结肠炎预后不良的独立危险因素(P<0.05)。血清miR-31、miR-155和CCL26水平在诊断溃疡性结肠炎发生预后不良具有较高的诊断效能,联合检测的灵敏度为80%,特异度为99.4%,AUC为0.963明显高于单个指标miR-31(z=2.727,P=0.006)、miR-155(z=3.012,P=0.003)和CCL26(z=2.091,P=0.036)。结论miR-31、miR-155和CCL26参与了溃疡性结肠炎的发生发展,与溃疡性结肠炎的严重程度有关,联合检测有助于提高对溃疡性结肠炎2年内发生预后不良的诊断价值。

Intestinal epithelial chemokine (C-C motif) ligand 7 overexpression protects against high fat diet-induced obesity and hepatic steatosis in mice

Background:We previously found that the intestinal epithelial chemokine(C-C motif)ligand 7(CCL7)plays an important role in the development of toxin-induced acute liver damage.The detailed effects of intestinal epithelial CCL7 on chronic diseases;however,are still unclear.Here,we aimed to investigate the impact of intestinal epithelial CCL7 overexpression on high-fat diet(HFD)-induced obesity and steatohepatitis in mice.Methods:Intestinal epithelial CCL7 overexpression(CCL7tgIEC)mice and their wild-type(WT)littermates were fed with normal chow or HFD for 16 weeks to induce obesity and non-alcoholic fatty liver disease.Body weight gain,as well as adipose tissue index were assessed.Liver injury was monitored by histological analysis and real time polymerase chain reaction.Gut microbial composition was analyzed by 16S rRNA gene sequencing.Results:We found that the CCL7tgIEC mice on a HFD had markedly decreased weight gain(8.9 vs.17.0 g,P<0.05)and a lower adipose tissue index that include mesenteric fat(1.0%vs.1.76%,P<0.05),gonadal fat(2.1%vs.6.1%,P<0.05),subcutaneous fat(1.0%vs.2.8%,P<0.05)compared to WT animals.HFD-induced glucose intolerance and insulin resistance were also significantly improved in CCL7tgIEC mice compared to WT.Furthermore,HFD-fed CCL7tgIEC mice displayed less hepatic lipid accumulation and lower expression of inflammatory factors than WT mice.16S rRNA gene sequencing demonstrated that CCL7 overexpression in intestinal epithelial cells improved HFD-induced gut microbial dysbiosis.Conclusions:Our study revealed that CCL7 overexpression in the intestinal epithelium protects mice against the progression of diet-induced obesity,hepatic steatosis,and enteric dysbiosis.

外周血CCL26、CCR3表达与变应性鼻炎患者疾病严重程度的关系

目的检测外周血趋化因子配体26(CCL26)、CC趋化因子受体-3(CCR3)表达水平,并探讨其与变应性鼻炎(AR)患者疾病严重程度的关系。方法选取2018年1月至2020年1月在上海市奉贤区奉城医院耳鼻喉科收治的86例AR患者作为研究组,根据病情的严重程度将所有AR患者分为轻度AR组(30例)、中度AR组(27例)和重度AR组(29例),另选取同时期在我院保健科体检的91例健康志愿者作为对照组。采用酶联免疫吸附法(ELISA)检测所有受检者的外周血CCL26表达水平,采用流式细胞仪检测外周血CCR3淋巴细胞百分率;采用Pearson相关分析法分析AR患者外周血CCL26、CCR3表达水平与过敏性鼻炎评分量表(SFAR)评分的相关性;采用受试者工作特征曲线(ROC)曲线分析CCL26、CCR3对AR的诊断价值;采用多因素Logistic回归分析影响AR的危险因素。结果研究组患者的外周血CCL26、CCR3表达水平分别为(4.83±1.07)ng/L、(40.63±9.25)%,明显高于对照组的(2.44±0.39)ng/L、(20.41±5.39)%,差异均有统计学意义(P<0.05);研究组患者中,IgE阳性者外周血CCL26、CCR3表达水平明显低于IgE阴性者,SFAR<7者外周血CCL26、CCR3表达水平明显低于SFAR≥7者,差异均有统计学意义(P<0.05);轻度AR组患者外周血CCL26、CCR3表达水平分别为(3.86±0.97)ng/L、(35.44±8.66)%,中度AR组分别为(4.99±1.02)ng/L、(40.21±9.45)%,重度AR组分别为(5.69±1.23)ng/L、(46.38±9.68)%,重度AR组的外周血CCL26、CCR3表达水平均明显高于轻度AR组和中度AR组,差异有统计学意义(P<0.05);经Pearson相关分析法分析结果显示,AR患者外周血CCL26、CCR3表达水平与SFAR评分呈正相关(P<0.05);经ROC曲线分析结果显示,CCL26、CCR3诊断AR患者的曲线下面积(AUC)分别为0.697(敏感度为51.2%,特异性为87.9%)、0.752(敏感度为62.8%,特异性为84.6%),两者联合检测的AUC为0.833,敏感度为73.3%,特异性为86.8%;多因素Logistic回归分析表明,CCL26、CCR3是AR发生的独立危险因素(P<0.05)。结论CCL26、CCR3的表达水平与AR的发生有关,可作为AR患者诊断的生物标记物。

Neuroinflammation in mild respiratory COVID‑19:insights into cognitive impairment in milder cases

Severe acute respiratory syndrome coronavirus 2(SARSCoV-2)infection has been extensively shown to cause many neurological sequelae,and cognitive deficits(known as“brain fog”)may particularly and widely occur even in individuals with mild symptoms[1].Peripheral hyperinflammation as well as central nervous system(CNS)local immune responses may synergistically contribute to brain autoimmune injury.In addition to the direct neuroinvasion of SARS-CoV-2 and nonimmune effects such as severe systemic hypoxemia and vascular thrombosis,the central mechanism by which SARSCoV-2 accelerates cognitive-related symptoms may be related to immune effects[2].However,the precise neuroinflammatory mechanisms of SARS-CoV-2 infection have not been fully established.Fernández-Casta-da et al.[3]provided direct evidence and unique insights into the potential mechanism of cognitive impairment in mild respiratory coronavirus disease 2019(COVID-19)cases.

Transforming growth factor-β and toll-like receptor-4 polymorphisms are not associated with fibrosis in haemochromatosis

AIM:To investigate the role of genetic polymorphisms in the progression of hepatic fibrosis in hereditary haemochromatosis.METHODS:A cohort of 245 well-characterised C282Y homozygous patients with haemochromatosis was studied,with all subjects having liver biopsy data and DNA available for testing.This study assessed the association of eight single nucleotide polymorphisms(SNPs)in a total of six genes including toll-like receptor 4(TLR4),transforming growth factor-beta(TGF-β),oxoguanine DNA glycosylase,monocyte chemoattractant protein 1,chemokine C-C motif receptor 2 and interleukin-10 with liver disease severity.Genotyping was performed using high resolution melt analysis and sequencing.The results were analysed in relation to the stage of hepatic fibrosis in multivariate analysis incorporating other cofactors including alcohol consumption and hepatic iron concentration.RESULTS:There were significant associations between the cofactors of male gender(P=0.0001),increasing age(P=0.006),alcohol consumption(P=0.0001),steatosis(P=0.03),hepatic iron concentration(P<0.0001)and the presence of hepatic fibrosis.Of the candidate gene polymorphisms studied,none showed a significant association with hepatic fibrosis in univariate or multivariate analysis incorporating cofactors.We also specifically studied patients with hepatic iron loading above threshold levels for cirrhosis and compared the genetic polymorphisms between those with no fibrosis vs cirrhosis however there was no significant effect from any of the candidate genes studied.Importantly,in this large,well characterised cohort of patients there was no association between SNPs for TGF-βor TLR4and the presence of fibrosis,cirrhosis or increasing fibrosis stage in multivariate analysis.CONCLUSION:In our large,well characterised group of haemochromatosis subjects we did not demonstrate any relationship between candidate gene polymorphisms and hepatic fibrosis or cirrhosis.

Expression Changes of Serum IL-1α,CCL2,and CXCL2 in Patients With Pemphigus

Objective:This study was performed to explore the possible changes of the serum levels of the cytokines including interleukin 1α(IL-1α),chemokine monocyte chemotactic protein 1(also known as chemokine[C-C motif]ligand 2[CCL2]),and C-X-C motif chemokine ligand 2(CXCL2)in patients with pemphigus.Methods:The expression levels of IL-1α,CCL2,and CXCL2 in the serum of 57 patients with pemphigus PV(including 42 patients in progressive stage and 15 patients in remission stage)and 31 healthy controls were examined by enzyme-linked immunosorbent assay.The indepent-samples t-test was used to compare the two groups.Oneway analysis of variance was used for multiple-group comparisons,and the post-hoc least significant difference test was used to detect differences among multiple groups.Results:The serum expression levels of CCL2 and IL-1a were all significantly higher in the patients in progressive stage than in the controls([2.69±0.23]ng/mL vs.[2.55±0.28]ng/mL,P=0.043;[0.62±0.27]ng/mL vs.[0.48±0.23]ng/mL,P=0.038,respectively).In addition,the serum expression level of CXCL2 was significantly higher in patients in progressive stage than in in the remission stage([61.70±46.38]ng/mL vs.[24.97±18.46]ng/mL,P=0.037).Sex,disease classification,disease severity,treatment,and mucosal involvement had no significant influence on the expression of IL-1α,CCL2,or CXCL2 in the serum of patients groups and controls(all P>0.05).Conclusion:IL-1α,CCL2,and CXCL2 are heavily involved in the occurrence and development of pemphigus and may be related to the activity of the disease.

Spinal CCL2 Promotes Central Sensitization, Long-Term Potentiation, and Inflammatory Pain via CCR2： Further Insights into Molecular, Synaptic, and Cellular Mechanisms

Mounting evidence supports an important role of chemokines, produced by spinal cord astrocytes, in promoting central sensitization and chronic pain. In particular, CCL2 （C-C motif chemokine ligand 2） has been shown to enhance N-methyl-D-aspartate （NMDA）-induced currents in spinal outer lamina II （Iio） neurons. However, the exact molecular, synaptic, and cellular mechanisms by which CCL2 modulates central sensitization are still unclear. We found that spinal injection of the CCR2 antagonist RS504393 attenuated CCL2- and inflammation-induced hyperalgesia. Single-cell RT-PCR revealed CCR2 expres- sion in excitatory vesicular glutamate transporter subtype 2-positive （VGLUT2＋） neurons. CCL2 increased NMDA- induced currents in CCR2＋/VGLUT2＋ neurons in lamina IIo; it also enhanced the synaptic NMDA currents evoked by dorsal root stimulation; and furthermore, it increased the total and synaptic NMDA currents in somatostatin- expressing excitatory neurons. Finally, intrathecal RS504393 reversed the long-term potentiation evoked in the spinal cord by C-fiber stimulation. Our findings suggest that CCL2 directly modulates synaptic plasticity in CCR2- expressing excitatory neurons in spinal lamina Iio, and this underlies the generation of central sensitization in patho- logical pain.

Spinal CCL2 Promotes Pain Sensitization by Rapid Enhancement of NMDA-Induced Currents Through the ERK-GluN2B Pathway in Mouse Lamina Ⅱ Neurons

Previous studies have shown that CCL2(C-C motif chemokine ligand 2)induces chronic pain,but the exact mechanisms are still unknown.Here,we established models to explore the potential mechanisms.Behavioral experiments revealed that an antagonist of extracellular signal-regulated kinase(ERK)inhibited not only CCL2-induced inflammatory pain,but also pain responses induced by complete Freund’s adjuvant.We posed the question of the intracellular signaling cascade involved.Subsequent experiments showed that CCL2 up-regulated the expression of phosphorylated ERK(pERK)and N-methyl D-aspartate receptor[NMDAR]subtype 2B(GluN2B);meanwhile,antagonists of CCR2 and ERK effectively reversed these phenomena.Whole-cell patchclamp recordings revealed that CCL2 enhanced the NMDAR-induced currents via activating the pERK pathway,which was blocked by antagonists of GluN2B and ERK.In summary,we demonstrate that CCL2 directly interacts with CCR2 to enhance NMDAR-induced currents,eventually leading to inflammatory pain mainly through the CCL2-CCR2-pERK-GluN2B pathway.

Functional roles of CCL5/RANTES in liver disease

Inflammation,which is mediated by leukocyte trafficking and activation,plays a prominent role in the pathogenesis of acute and chronic liver injury.Chemokines are critical mediators involved in the migration of leukocytes into the diseased liver via binding to their G protein-coupled receptors.CeC motif ligand 5(CCL5)belongs to the CC-chemokine family and is secreted by several hepatic cell pop-ulations including hepatocytes,macrophages,hepatic stellate cells,and endothelial cells upon activation.CCL5 regulates the recruitment and migration of T cells(via CCR5)and NK cells(via CCR1).Moreover,CCL5 activates and stimulates T cell proliferation and cytokine production,sequentially regulating in-flammatory responses.Accumulating studies have identified crucial effects of CCL5 both in liver-disease patients and in experimental models,in which CCL5 is elevated and displays distinct effects according to pathological conditions.In this review,we discussed the crucial functions of CCL5 in liver diseases,including acute liver failure,hepatic ischemia-reperfusion injury,acute liver failure,acute and viral hepatitis,alcoholic liver disease,non-alcoholic fatty liver disease,fibrosis,and hepatocellular carcinoma.Continued understanding the roles of CCL5 in liver disease and their mechanisms of activation are indispensable for the development of effective clinical therapeutics.

CCL16 inhibits tumor proliferation and metastasis in HCC by impacting CK19 phenotype

Background and aims:Cytokeratin 19-positive(CK19t)hepatocellular carcinoma(HCC)is an aggressive subtype with poor outcomes.The initiation and development of CK19t HCC in the background of liver cirrhosis remains unclear.This study investigated the role of the cirrhosis-related gene C-C motif chemokine ligand 16(CCL16)in the development of CK19t HCC.Methods:Datasets from Gene Expression Omnibus(GEO),The Cancer Genome Atlas(TCGA)and International Cancer Genome Consortium(ICGC)were analyzed to screen and validate the genes associated with CK19t HCC.A total of 102 HCC patients were included for tissue microarray analysis.Gain-of-function experiments were conducted to investigate the biological functions of CCL16.CIBERSORT was used to investigate the correlation of CCL16 and immune infiltration.Results:GEO dataset analysis showed that CK19t HCC had lower expression of CCL16.In both TCGA dataset and our HCC cohort,CCL16 expression was negatively correlated with CK19 expression(P<0.05)and its expression was higher in para-tumor than tumor tissues(P<0.001).Moreover,low CCL16 expression was related to advanced stage and poor overall survival(P<0.05).CCL16 overexpression downregulated CK19 expression and impacted the sphere formation ability of HCC cells.Overexpression of CCL16 inhibited the cell proliferation,migration,and invasion of HCC cell lines.Immune analysis showed HCC with high CCL16 expression had more infiltration of mast cells.HCC patients with both low CCL16 expression and low mast cells had the worst prognosis(P<0.001).Conclusion:Our data indicated that CCL16 downregulated the expression of CK19 and inhibited the malignant phenotype of HCC.