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*

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 investigate the effect of monocyte chemotactic protein-3 (MCP-3) on the expressions of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), tissue factor (TF, and tissue factor pathway inhibitor (TFPI) and cell apoptosis in human umbilical vein endothelial cells (HUVECs).

METHODSCultured HUVECs were treated with MCP-3 at the optimal concentration determined previously 1 h after treatments with or without MCP-3 antibody (20 ng/ml), PI3K inhibitor, or LY-294002 (5 mmol/ml). The expressions of ICAM-1, VCAM-1, TF and TFPI were analyzed using RT-PCR and Western blot after the treatments. MCP-3 mRNA and protein expressions were detected in HUVECs exposed to 50 µg/ml ox-LDL for 24 h. The cell apoptosis and caspase-3 protein production in HUVECs treated with MCP-3 or with MCP-3 plus CCR2 antagonist for 24 h and 48 h were evaluated by flow cytometry and Western blotting.

RESULTSAt the optimal concentration of 0.3 ng/ml, MCP-3 treatment for 24 h caused significantly increased ICAM-1, VCAM-1, and TF expressions with lowered expression of TFPI in HUVECs (P<0.05), and such effects were significantly inhibited by the application of MCP-3 antibody, PI3K inhibitor, or LY-294002 (P<0.05). Ox-LDL exposure significantly increased the expression of MCP-3 in HUVECs (P<0.05). HUVECs showed a significantly increased apoptosis rate after treatment with MCP-3 or with MCP-3 plus CCR2 antagonist (P<0.05), and the apoptosis rate increased significantly as the treatment time prolonged (P<0.05); caspase-3 protein expression in the cells showed a similar pattern of alterations following the treatments.

CONCLUSIONox-LDL can induce MCP-3 expression in HUVECs. MCP-3 induces apoptosis of HUVECs and significantly affects the cellular function partially through the PI3K signaling pathway.

Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Cell Adhesion ; Cells, Cultured ; Chemokine CCL7 ; pharmacology ; Chromones ; pharmacology ; Human Umbilical Vein Endothelial Cells ; cytology ; drug effects ; metabolism ; Humans ; Intercellular Adhesion Molecule-1 ; metabolism ; Lipoproteins ; metabolism ; Lipoproteins, LDL ; pharmacology ; Morpholines ; pharmacology ; Phosphatidylinositol 3-Kinases ; antagonists & inhibitors ; Receptors, CCR2 ; antagonists & inhibitors ; Signal Transduction ; Thromboplastin ; metabolism ; Vascular Cell Adhesion Molecule-1 ; metabolism

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

KR-31543, (2S, 3R, 4S)-6-amino-4-[N-(4-chlorophenyl)-N-(2-methyl-2H-tetrazol-5-ylmethyl) amino]-3,4-dihydro-2-dimethyoxymethyl-3-hydroxy-2-methyl-2H-1-benz opyran is a new neuroprotective agent for ischemia-reperfusion damage. It has also been reported that KR-31543 has protective effects on lipid peroxidation and H2O2-induced reactive oxygen species production. In this study, we investigated the anti-inflammatory and anti-atherogenic properties of KR-31543. We observed that KR-31543 treatment reduced the production of MCP-1, IL-8, and VCAM-1 in HUVECs, and of MCP-1 and IL-6 in THP-1 human monocytes. We also examined the effect of KR-31543 on monocytes migration in vitro. KR-31543 treatment effectively reduced the migration of THP-1 human monocytes to the HUVEC monolayer in a dose-dependent manner. We next examined the effects of this compound on atherogenesis in LDL receptor deficient (Ldlr-/-) mice. After 10 weeks of western diet, the formation of atherosclerotic lesion in aorta was reduced in the KR-31543-treated group compared to the control group. The accumulation of macrophages in lesion was also reduced in KR-31543 treated group. However, the plasma levels of total cholesterol, HDL, LDL, and triglyceride were not affected by KR-31543 treatment. Taken together, these results show that KR-31543 has anti-inflammatory properties on human monocytes and endothelial cells, and inhibits fatty streak lesion formation in mouse model of atherosclerosis, suggesting the potential of KR-31543 for the treatment for atherosclerosis.
Animals ; Aorta/pathology ; Atherosclerosis/blood/*drug therapy/pathology ; Benzopyrans/*pharmacology/therapeutic use ; Cholesterol, HDL/blood ; Cholesterol, LDL/blood ; Diet ; Disease Models, Animal ; Human Umbilical Vein Endothelial Cells/drug effects/metabolism ; Inflammation Mediators/*metabolism ; Interleukin-6/metabolism ; Interleukin-8/metabolism ; Macrophages/metabolism ; Mice ; Mice, Transgenic ; Monocytes/drug effects/*metabolism ; Neuroprotective Agents/*pharmacology/therapeutic use ; Receptors, CCR2/metabolism ; Receptors, LDL/genetics ; Tetrazoles/*pharmacology/therapeutic use ; Transendothelial and Transepithelial Migration/drug effects ; Triglycerides/blood ; Vascular Cell Adhesion Molecule-1/metabolism

Alcoholism ; metabolism ; Animals ; Brain ; metabolism ; Chemokine CCL2 ; genetics ; metabolism ; Male ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptors, CCR2 ; genetics ; metabolism