Objective To explore the effect of Evodiamine (Evo) on the immune function of allergic rhinitis (AR) rats and the regulatory mechanism on C-C motif chemokine ligand 2 (CCL2)/ C-C motif chemokine receptor 2 (CCR2) pathway. Methods The related targets of Evo-AR-immune function were screened by network pharmacology, and the protein interaction network diagram of intersecting targets was constructed. The AR rat model was established by ovalbumin (OVA) combined with aluminium hydroxide, and the rats were divided into six groups: a normal control (NC) group, a model group, a Loratadine (LOR) group, an Evodiamine low dose (Evo-L) group, a Evodiamine high dose (Evo-H) groups, and an Evo-H combined with CCL2 group. After the last administration, the symptoms of rats in each group were scored; ELISA was applied to detect the levels of histamine, immunoglobulin E (IgE), interleukin 4 (IL-4), IL-13 and interferon γ (IFN-γ); Diff-Quick staining solution was applied to detecte the number of cells in the nasal lavage fluid (NALF); hematoxylin eosin (HE) staining was applied to observe the pathological changes of nasal mucosa tissue; real-time quantitative PCR was applied to detect the levels of CCL2 and CCR2 mRNA in tissue; Western blot was applied to detect the expression levels of CCL2, CCR2 and CXC motif chemokine ligand 8 (CXCL8) proteins in nasal mucosa. Results There were eight intersection targets of EVo-AR-immune function, and protein interaction network diagram showed that CXCL8 was the core target. Compared with the NC group, the score of nasal symptoms, the levels of histamine, IgE, IL-4 and IL-13, the numbers of eosinophil, macrophages, neutrophils, lymphocytes and total cells, the mRNA and protein expression levels of CCL2 and CCR2, and the expression of CXCL8 protein in the model group were increased, while the level of IFN-γ was decreased. Compared with the model group, the score of nasal symptoms, the levels of histamine, IgE, IL-4 and IL-13, the numbers of eosinophil, macrophages, neutrophils, lymphocytes and total cells, the mRNA and protein expression levels of CCL2 and CCR2, and the expression of CXCL8 protein in LOR and Evo groups were decreased, while the level of IFN-γ was increased. Further use of CCL2 recombinant protein for compensatory experiments revealed that the improvement effect of Evo on immune function in AR rats was reversed by CCL2. Conclusion Evo can improve the immune function of AR rats, and its mechanism may be related to the inhibition of the CCL2/CCR2 pathway.
Animals ; Receptors, CCR2/immunology* ; Signal Transduction/drug effects* ; Chemokine CCL2/immunology* ; Rats ; Rhinitis, Allergic/metabolism* ; Immunoglobulin E/blood* ; Quinazolines/pharmacology* ; Male ; Interferon-gamma ; Rats, Sprague-Dawley ; Interleukin-13 ; Histamine ; Interleukin-4/immunology* ; Disease Models, Animal

Chronic pain, frequently comorbid with neuropsychiatric disorders, significantly impairs patients' quality of life and functional capacity. Accumulating evidence implicates the chemokine CCL2 and its receptor CCR2 as key players in chronic pain pathogenesis. This review examines the regulatory mechanisms of the CCL2/CCR2 axis in chronic pain processing at three hierarchical levels: (1) Peripheral Sensitization: CCL2/CCR2 modulates TRPV1, Nav1.8, and HCN2 channels to increase neuronal excitability and CGRP signaling and calcium-dependent exocytosis in peripheral nociceptors to transmit pain. (2) Spinal Cord Central Sensitization: CCL2/CCR2 contributes to NMDAR-dependent plasticity, glial activation, GABAergic disinhibition, and opioid receptor desensitization. (3) Supraspinal Central Networks: CCL2/CCR2 signaling axis mediates the comorbidity mechanisms of pain with anxiety and cognitive impairment within brain regions, including the ACC, CeA, NAc, and hippocampus, and it also increases pain sensitization through the descending facilitation system. Current CCL2/CCR2-targeted therapeutic strategies and their development status are discussed, highlighting novel avenues for chronic pain management.
Humans ; Chronic Pain/physiopathology* ; Animals ; Neuroglia/metabolism* ; Chemokine CCL2/metabolism* ; Receptors, CCR2/metabolism*

The CC chemokine ligand 2 (CCL2, also known as MCP-1) and its cognate receptor CCR2 have well-characterized roles in chemotaxis. CCL2 has been previously shown to promote excitatory synaptic transmission and neuronal excitability. However, the detailed molecular mechanism underlying this process remains largely unclear. In cultured hippocampal neurons, CCL2 application rapidly upregulated surface expression of GluA1, in a CCR2-dependent manner, assayed using SEP-GluA1 live imaging, surface GluA1 antibody staining, and electrophysiology. Using pharmacology and reporter assays, we further showed that CCL2 upregulated surface GluA1 expression primarily via Gα_q- and CaMKII-dependent signaling. Consistently, using i.p. injection of lipopolysaccharide to induce neuroinflammation, we found upregulated phosphorylation of S831 and S845 sites on AMPA receptor subunit GluA1 in the hippocampus, an effect blocked in Ccr2^-/- mice. Together, these results provide a mechanism through which CCL2, and other secreted molecules that signal through G-protein coupled receptors, can directly regulate synaptic transmission.
Animals ; Receptors, AMPA/metabolism* ; Chemokine CCL2/metabolism* ; Hippocampus/drug effects* ; Neurons/drug effects* ; Synaptic Transmission/drug effects* ; Mice ; Receptors, CCR2/metabolism* ; Protein Transport/drug effects* ; Mice, Inbred C57BL ; Cells, Cultured ; Mice, Knockout ; Excitatory Postsynaptic Potentials/drug effects* ; Rats

The present study was designed to establish a suitable assay to explore CCR2b receptor antagonists from the natural products of Artemisia rupetris and Leontopodium leontopodioides. An aequorin assay was developed as a cell-based assay suitable for 384-well microplate and used for screening CCR2b receptor antagonists from natural products. Through establishing suitable conditions, the assay was shown to be suitable for screening of CCR2b receptor antagonists. Seven compounds were identified in preliminary screening. Five of them showed evident dose-response relationship in secondary screening. The structure-activity relationship study suggested that 7-position hydroxyl group of flavonoids was necessary, a polar group should be introduced on the 3-position, and the substituents on 2-position benzene ring of flavonoids have little influence on the potentency of the inhibition activity on CCR2b receptor. The ortho-position dihydroxyl structure in quinic acid compounds may be important. In conclusion, Compounds HR-1, 5, 7, and AR-20, 35 showed activity as antagonist of CCR2b receptor, which shed lights on the development of novel drugs as CCR2b receptor antagonists for preventing inflammation related diseases.
Artemisia ; chemistry ; Asteraceae ; chemistry ; Drug Evaluation, Preclinical ; Humans ; Kinetics ; Plant Extracts ; chemistry ; pharmacology ; Receptors, CCR2 ; antagonists & inhibitors ; genetics ; metabolism ; Structure-Activity Relationship

Hypoxic-ischemic brain damage (HIBD) is referred to a common type of cerebral damage, which is caused by injury, leading to shallow bleeding in the cortex with intact cerebral pia mater. In recent years, studies show that a various kinds of immune cells and immune cellular factors are involved in the occurrence of HIBD. CC chemokine receptor 2 (CCR2) is a representative of CC chemokine receptor, and is widely distributed in cerebral neuron, astrocyte, and microglial cells, and is the main chemo-tactic factor receptor in brain tissue. CC chemokine ligand 2 (CCL2) is a kind of basophilic protein and the ligand of CCR2, and plays an important role in inflammation. In order to provide evidence for correlational studies in HIBD, this review will introduce the biological characteristics of CCR2 and CCL2, and illustrate the relationship between the immunoreactivity and HIBD.
Animals ; Brain Injuries/pathology* ; Cerebral Cortex/physiopathology* ; Chemokine CCL2/metabolism* ; Chemokines, CC/metabolism* ; Hypoxia-Ischemia, Brain/metabolism* ; Macrophage Inflammatory Proteins/metabolism* ; RNA, Messenger/metabolism* ; Rats ; Rats, Sprague-Dawley ; Receptors, CCR2/metabolism*

OBJECTIVETo investigate the association between rs1799864 single nucleotide polymorphism (SNP) of the C-C chemokine receptor 2 (CCR2) gene and susceptibility of hemophagocytic lymphohistiocytosis (HLH) in children.

METHODSThe clinical and laboratory data of 86 children diagnosed with HLH between January 2007 and December 2013 were retrospectively reviewed. The CCR2 gene rs1799864 was genotyped by SNaPshot technique in 86 HLH children and 128 healthy controls. The genotypic and allelic frequencies in the two groups were comparatively analyzed.

RESULTSNo significant difference either in genotypic or allelic frequencies of rs1799864 polymorphism of the CCR2 gene was observed between HLH patients and controls (P>0.05), but there were significant differences in the age of onset and the periods of temperature and platelet returning to normal after treatment (P<0.05).

CONCLUSIONSThere is no association between CCR2 gene rs1799864 polymorphism and the risk for HLH in children. However, the genotypic differences of this polymorphism might be associated with clinical characteristics and prognosis of HLH.

Child ; Child, Preschool ; Female ; Genotype ; Humans ; Lymphohistiocytosis, Hemophagocytic ; genetics ; Male ; Polymorphism, Single Nucleotide ; Receptors, CCR2 ; genetics

OBJECTIVETo determine the effects of transient receptor potential vanilloid type 1 (TRPV1) channel ablation and a chemokine receptor 2 (CCR2) antagonist on salt-sensitive hypertension-induced renal injury.

METHODSWild-type (WT) and TRPV1-null mutant (TRPV1(-/-)) mice were subjected to uninephrectomy and deoxycorticosterone acetate (DOCA)-salt treatment for 4 weeks with or without a CCR2 antagonist, RS504393 (n=8 for all the 4 groups). Sham WT and TRPV1(-/-) mice (both n=7) underwent uninephrectomy without receiving DOCA and saline. Systolic blood pressure, urinary excretion of albumin, 8-isoprostane and creatinine clearance for 24 hours were assayed during the experimental period and at the end of the 4-week treatment. The morphological analysis was performed in renal histological sections, including glomerulosclerosis, tubulointerstitial injury, and monocyte/macrophage infiltration.

RESULTSCompared to the corresponding control mice, DOCA-salt treatment in both WT and TRPV1(-/-) mice led to increased systolic blood pressure (SBP), enhanced urinary excretion of albumin and 8-isoprostane, decreased creatinine clearance, increased glomerulosclerosis and tubulointerstitial injury associated with enhanced monocyte/macrophage infiltration (all P<0.05), all of which were much more severe in TRPV1(-/-) mice compared to WT mice with the exception of blood pressure (all P<0.05). RS5043943 attenuated DOCA-salt-induced changes in renal function and morphology in WT and TRPV1(-/-) mice (all P<0.05). There was no difference in blood pressure among DOCA-salt WT and TRPV1(-/-) mice with or without RS505393 with the exception of sham WT and TRPV1(-/-) mice (all P>0.05).

CONCLUSIONSCCR2 antagonist inhibits DOCA-salt-induced renal injury and monocyte/macrophage infiltration in WT and TRPV1(-/-) mice with the greater in the latter strain. Activation of TRPV1 attenuates salt-sensitive hypertension-induced renal injury possibly via inhibition of CCR2-induced monocyte/macrophage infiltration.

Animals ; Hypertension ; complications ; pathology ; Kidney Diseases ; etiology ; pathology ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Receptors, CCR2 ; antagonists & inhibitors ; physiology ; Sodium Chloride ; adverse effects ; TRPV Cation Channels ; physiology

OBJECTIVE: To investigate the expression of monocyte chemotactic protein-1 (MCP-1) and its receptor CC chemokine receptor-2 (CCR-2) in coronary atherosclerosis plaques between sidden coronary death (SCD) and non-SCD. Methods The expression levels of MCP-1 and CCR-2 in SCD group, coronary atherosclerosis group (non-SCD), control group (normal coronary artery) were detected by immunohistochemistry. RESULTS: Positive rates of MCP-1 among the three groups were 78%, 47%, and 0%, respectively, with significant expressing differences between each two groups (P<0.05). Positive rates of CCR-2 among three groups were 72%, 47%, and 0%, respectively, with significant expressing differences between the SCD group and coronary atherosclerosis group as well as between the SCD group and control group (P<0.05), but with no significant expressing difference between coronary atherosclerosis group and control group (P>0.05). CONCLUSION Overexpression of MCP-1 and CCR-2 in coronary atherosclerotic plaques is closely correlated with SCD.
Chemokine CCL2/metabolism* ; Coronary Artery Disease/pathology* ; Death, Sudden, Cardiac/pathology* ; Humans ; Immunohistochemistry ; Receptors, CCR2/metabolism*

OBJECTIVETo assess the association of variations in chemokines (CCL5, CCL2), chemokine receptor (CCR5 and CCR2) genes with susceptibility to myocardial infarction (MI) through a case-control study.

METHODSGenotypes of patients with MI (n = 634) were compared with those of controls (n = 601). Genetic polymorphisms of CCL5 rs2107538 (-403G > A), CCL2 rs1024611 (-2518A > G), CCR5 rs333 ( δ 32 ins or del) and CCR2 rs1799864 (190G > A) of 1235 individuals were determined with polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Particular genotypes were confirmed with DNA sequencing.

RESULTSNo subject was found to carry the CCR5 - δ 32 allele. No association was found between CCL2 rs1024611 and CCR2 rs1799864 polymorphisms and MI. For CCL5 rs2107538 polymorphism, the A allele has occurred at a higher frequency in MI patients than controls, and its AA genotype has been associated with a significantly increased risk of MI independent of conventional risk factors (OR = 3.346, 95%CI = 1.938-5.775, P < 0.01, AA vs. GG). Further analysis indicated that MI patients had significantly more A-403 - A-2518 haplotype (CCL5 -403G > A and CCL2 -2518A > G, 21.8% vs. 26.6%, OR = 1.229, 95%CI = 1.012-1.493, P = 0.038) and AA or AA genotype (CCL5 -403G > A - CCL2 -2518A > G, 5.0% vs. 12.1%, OR = 3.245, 95%CI = 1.780-5.914, P < 0.01).

CONCLUSIONAlthough our data dose not support an association between CCL2 rs1024611, CCR2 rs1799864 and CCR5 rs333 polymorphisms and MI, genetic variation in CCL5 gene may still be a useful marker for assessing susceptibility to MI in ethnic Han Chinese population.

Aged ; Alleles ; Asian Continental Ancestry Group ; ethnology ; genetics ; Base Sequence ; Case-Control Studies ; Chemokine CCL2 ; chemistry ; Chemokine CCL5 ; genetics ; China ; epidemiology ; ethnology ; Female ; Genetic Association Studies ; Humans ; Male ; Middle Aged ; Molecular Sequence Data ; Myocardial Infarction ; epidemiology ; ethnology ; genetics ; Polymorphism, Single Nucleotide ; Receptors, CCR2 ; genetics ; Receptors, CCR5 ; genetics ; Risk Factors

OBJECTIVETo determine the role of chemokine receptor 2 (CCR2) in the development of salt-sensitive hypertension-induced renal damage.

METHODSWe investigated the renal damage induced by uninephrectomy and deoxycorticosterone acetate (DOCA)-salt in mice treated with or without a selective CCR2 antagonist RS504393 for 4 weeks. Sham mice underwent uninephrectomy without receiving DOCA and saline. Systolic blood pressure, urinary excretion of albumin and 8-isoprostane, creatinine clearance, glomerulosclerosis, renal tubulointerstitial injury, and renal monocyte/macrophage infiltration were measured.

RESULTSDOCA-salt treatment led to increased systolic blood pressure, increased urinary excretion of albumin and 8-isoprostane, decreased creatinine clearance, glomerulosclerosis, renal tubulointerstitial injury, and renal monocyte/macrophage infiltration compared with the sham mice (P<0.05). All of them were prevented by CCR2 inhibition (P<0.05).

CONCLUSIONBlockade of CCR2 prevents renal damage induced by DOCA-salt treatment, suggesting that CCR2-mediated monocyte/macrophage infiltration may contribute to salt-sensitive hypertension-induced renal injury.

Animals ; Disease Models, Animal ; Hypertension ; chemically induced ; physiopathology ; Kidney ; physiopathology ; Male ; Mice ; Mice, Inbred C57BL ; Receptors, CCR2 ; metabolism ; Sodium Chloride, Dietary ; toxicity