1.Neuroprotective effect and mechanism of Zuogui Jiangtang Jieyu Formula on diabetes mellitus complicated with depression model rats based on CX3CL1-CX3CR1 axis.
Ping LI ; Yang LIU ; Man-Shu ZOU ; Ting-Ting WANG ; Hai-Peng GUO ; Ting-Ting REN ; Ying HE ; Hua WANG ; Yu-Hong WANG
China Journal of Chinese Materia Medica 2023;48(21):5822-5829
Based on the CX3C chemokine ligand 1(CX3CL1)-CX3C chemokine receptor 1(CX3CR1) axis, this study explored the potential mechanism by which Zuogui Jiangtang Jieyu Formula(ZGJTJY) improved neuroinflammation and enhanced neuroprotective effect in a rat model of diabetes mellitus complicated with depression(DD). The DD rat model was established by feeding a high-fat diet combined with streptozotocin(STZ) intraperitoneal injection for four weeks and chronic unpredictable mild stress(CUMS) combined with isolated cage rearing for five weeks. The rats were divided into a control group, a model group, a positive control group, an inhibitor group, and a ZGJTJY group. The open field test and forced swimming test were used to assess the depression-like behaviors of the rats. Enzyme-linked immunosorbent assay(ELISA) was performed to measure the expression levels of the pro-inflammatory cytokines interleukin-1β(IL-1β) and tumor necrosis factor-α(TNF-α) in plasma. Immunofluorescence staining was used to detect the expression of ionized calcium-binding adapter molecule 1(Iba1), postsynaptic density protein-95(PSD95), and synapsin-1(SYN1) in the hippocampus. Hematoxylin-eosin(HE) staining, Nissl staining, and TdT-mediated dUTP nick end labeling(TUNEL) fluorescence staining were performed to assess hippocampal neuronal damage. Western blot was used to measure the expression levels of CX3CL1, CX3CR1, A2A adenosine receptor(A2AR), glutamate receptor 2A(NR2A), glutamate receptor 2B(NR2B), and brain-derived neurotrophic factor(BDNF) in the hippocampus. Compared with the model group, the ZGJTJY group showed improved depression-like behaviors in DD rats, enhanced neuroprotective effect, increased expression of PSD95, SYN1, and BDNF(P<0.01), and decreased expression of Iba1, IL-1β, and TNF-α(P<0.01), as well as the expression of CX3CL1, CX3CR1, A2AR, NR2A, and NR2B(P<0.01). These results suggest that ZGJTJY may exert its neuroprotective effect by inhibiting the CX3CL1-CX3CR1 axis and activation of hippocampal microglia, thereby improving neuroinflammation and abnormal activation of N-methyl-D-aspartate receptor(NMDAR) subunits, and ultimately enhancing the expression of synaptic-related proteins PSD95, SYN1, and BDNF in the hippocampus.
Rats
;
Animals
;
Depression/drug therapy*
;
Brain-Derived Neurotrophic Factor
;
Neuroprotective Agents
;
Tumor Necrosis Factor-alpha/metabolism*
;
Neuroinflammatory Diseases
;
Diabetes Mellitus
;
Receptors, Glutamate
;
CX3C Chemokine Receptor 1/genetics*
2.Yigong Powder regulates CXCL12/CXCR4 signaling to reduce glutamate release and prevent cognitive decline in mouse model of aging.
Jiang-Ping WEI ; Zi-Xuan ZHAO ; Jing ZENG ; Fang-Hong SHANG ; Lei HUA ; Yong YANG ; Xiao-Mei ZHANG
China Journal of Chinese Materia Medica 2023;48(23):6483-6491
This study aims to explore the effect of preventive administration of Yigong Powder on the learning and memory abilities of the mouse model of aging induced by D-galactose and decipher the underlying mechanism, so as to provide a basis for the application of Yigong Powder in the prevention and treatment of cognitive decline. Forty KM mice were randomized into control, model, donepezil(1.5 mg·kg~(-1)), and high-dose(7.5 g·kg~(-1)) and low-dose(3.75 g·kg~(-1)) Yigong Powder groups. The mice in other groups except the control group were injected with D-galactose(200 g·kg~(-1)) at the back of the neck for the modeling of aging. At the same time, the mice were administrated with corresponding drugs by gavage for one month. Morris water maze was used to examine the learning and memory abilities of the mice. Hematoxylin-eosin staining was employed to observe the pathological and morphological changes of the hippocampus. The immunofluorescence assay was employed to detect the expression of ionized calcium-binding adapter molecule 1(IBA1), glial fibrillary acidic protein(GFAP), chemokine C-X-C-motif ligand 12(CXCL12), chemokine C-X-C-motif receptor 4(CXCR4) in the hippocampus and observe the positional relationship between IBA1, GFAP, and CXCR4. Western blot was employed to determine the protein levels of extracellular regulated kinase(ERK), p-ERK, and tumor necrosis factor receptor 1(TNFR1). Enzyme-linked immunosorbent assay was employed to measure the levels of glutamate and tumor necrosis factor(TNF-α) in the brain tissue and the level of TNF-α in the serum and spleen. Yigong Powder significantly shortened the escape latency, increased the times crossing platforms, and prolonged the cumulative time in quadrants of the aging mice. It alleviated the nerve cell disarrangement, increased intercellular space, and cell degeneration or death in the hippocampus and reduced the pathology score of the damaged nerve. Moreover, Yigong Powder reduced the positive area of IBA1 and GFAP, reduced the levels of TNF-α in the brain tissue, serum, and spleen, and decreased spleen index. Furthermore, Yigong Powder decreased the average fluorescence intensity of CXCL12 and CXCR4, reduced CXCR4-positive astrocytes and microglia, down-regulated the protein levels of p-ERK/ERK and TNFR1, and lowered the level of glutamate in the brain tissue. This study showed that the preventive administration of Yigong Powder can ameliorate the learning and memory decline of the D-galactose-induced aging mice by regulating the immune function of the spleen and the CXCL12/CXCR4 signaling in the brain to reduce glutamate release. However, the mechanism of Yigong San in preventing and treating dementia via regulating spleen and stomach function remains to be studied.
Mice
;
Animals
;
Powders
;
Receptors, Tumor Necrosis Factor, Type I
;
Glutamic Acid
;
Tumor Necrosis Factor-alpha/metabolism*
;
Galactose/adverse effects*
;
Disease Models, Animal
;
Cognitive Dysfunction/prevention & control*
;
Chemokines
;
Drugs, Chinese Herbal
3.miR-148b inhibits M2 polarization of LPS-stimulated macrophages by targeting DcR3.
Li Yuan YANG ; Xiao Li LOU ; Yue WANG ; Yan Qiang HOU
Chinese Journal of Preventive Medicine 2023;57(8):1231-1237
Objective: To investigate the effect of microRNA (miR-148b) targeting decoy receptor 3 (DcR3) on macrophage polarization in sepsis. Methods: Experimental study. From December 2019 to December 2022, serum microRNA expression was detected in 3 patients with sepsis and 3 healthy controls in the clinical laboratory of Songjiang Hospital Affiliated to Shanghai Jiao Tong University School of Medicine. Phorbol 12-myristate 13-acetate (PMA) was used to induce the differentiation of human acute monocytic leukemia cells THP-1 into macrophages, and then lipopolysaccharide (LPS) was added to stimulate the establishment of a sepsis cell model, and the expression changes of miR-148b and DcR3 were detected by RT-PCR and Western blot. Overexpression of DcR3 was used to detect the expression levels of TNF-α, CD163 and IL-10 in macrophages stimulated by LPS (100 ng/ml). Overexpression of miR-148b was used to observe the changes of molecular markers of macrophage polarization. The targeting regulation effect of miR-148b on DcR3 was determined by dual-luciferase reporter assay. t test was used to analyze whether there were statistical differences among the groups. Results: The expression of miR-148b was down-regulated (P<0.05) and the expression of DcR3 was up-regulated (P<0.01) in THP-1 macrophages stimulated by LPS. Overexpression of DcR3 inhibited the expression of TNF-α (P<0.05) and promoted the expression of CD163 (P<0.01) and IL-10 (P<0.01). When miR-148b mimics was added, the opposite effect was observed. The dual-luciferase reporter assay confirmed that miR-148b targets and binds to DcR3, inhibiting its transcription and expression. The results of flow cytometry showed that DcR3 could reverse the promoting effect of miR-148b on the CD86/CD163 ratio of macrophages (P<0.05). Conclusion: miR-148b inhibits the expression of DcR3, thereby inhibiting M2 polarization in LPS-stimulated macrophage cells.
Humans
;
Interleukin-10
;
Lipopolysaccharides/pharmacology*
;
Macrophages
;
MicroRNAs/genetics*
;
Receptors, Tumor Necrosis Factor, Member 6b/metabolism*
;
Tumor Necrosis Factor-alpha
4.miR-148b inhibits M2 polarization of LPS-stimulated macrophages by targeting DcR3.
Li Yuan YANG ; Xiao Li LOU ; Yue WANG ; Yan Qiang HOU
Chinese Journal of Preventive Medicine 2023;57(8):1231-1237
Objective: To investigate the effect of microRNA (miR-148b) targeting decoy receptor 3 (DcR3) on macrophage polarization in sepsis. Methods: Experimental study. From December 2019 to December 2022, serum microRNA expression was detected in 3 patients with sepsis and 3 healthy controls in the clinical laboratory of Songjiang Hospital Affiliated to Shanghai Jiao Tong University School of Medicine. Phorbol 12-myristate 13-acetate (PMA) was used to induce the differentiation of human acute monocytic leukemia cells THP-1 into macrophages, and then lipopolysaccharide (LPS) was added to stimulate the establishment of a sepsis cell model, and the expression changes of miR-148b and DcR3 were detected by RT-PCR and Western blot. Overexpression of DcR3 was used to detect the expression levels of TNF-α, CD163 and IL-10 in macrophages stimulated by LPS (100 ng/ml). Overexpression of miR-148b was used to observe the changes of molecular markers of macrophage polarization. The targeting regulation effect of miR-148b on DcR3 was determined by dual-luciferase reporter assay. t test was used to analyze whether there were statistical differences among the groups. Results: The expression of miR-148b was down-regulated (P<0.05) and the expression of DcR3 was up-regulated (P<0.01) in THP-1 macrophages stimulated by LPS. Overexpression of DcR3 inhibited the expression of TNF-α (P<0.05) and promoted the expression of CD163 (P<0.01) and IL-10 (P<0.01). When miR-148b mimics was added, the opposite effect was observed. The dual-luciferase reporter assay confirmed that miR-148b targets and binds to DcR3, inhibiting its transcription and expression. The results of flow cytometry showed that DcR3 could reverse the promoting effect of miR-148b on the CD86/CD163 ratio of macrophages (P<0.05). Conclusion: miR-148b inhibits the expression of DcR3, thereby inhibiting M2 polarization in LPS-stimulated macrophage cells.
Humans
;
Interleukin-10
;
Lipopolysaccharides/pharmacology*
;
Macrophages
;
MicroRNAs/genetics*
;
Receptors, Tumor Necrosis Factor, Member 6b/metabolism*
;
Tumor Necrosis Factor-alpha
5.Activation of cannabinoid receptor 2 alleviates acute lung injury in rats with lipopolysaccharide-induced sepsis.
Hui Wen KANG ; Shou Fang JIANG ; Qian SONG ; Yi Li ZHANG
Journal of Southern Medical University 2022;42(9):1374-1380
OBJECTIVE:
To investigate the protective effect of cannabinoid receptor 2 (CB2) activation against acute lung injury in rats with lipopolysaccharide (LPS)-induced sepsis and explore the underlying mechanism.
METHODS:
Forty-eight SD rats were randomly assigned into control group, model group, CB2 agonist group and P38 MAPK inhibitor group (n=12). In the latter 3 groups, the rats received intraperitoneal injection of LPS to induce sepsis, and the control rats were given saline injection. In CB2 agonist group, JWH133 (3 mg/kg) was injected intraperitoneally 30 min before LPS injection; in P38 MAPK inhibitor group, the rats received intraperitoneal injection of SB203580 (5 mg/kg) 30 min prior to JWH133 injection. The changes in lung histopathology, water content, fluid clearance rate, inflammatory factors, pulmonary expressions of CB2 and tight junctionrelated genes, and phosphorylation of P38 MAPK in the lung tissues were examined.
RESULTS:
The rat models of sepsis showed severe damage of alveolar structures with significantly decreased fluid clearance rate, lowered pulmonary expressions of CB2, occludin and ZO-1 mRNA and proteins, increased water content in the lung tissue, and increased phosphorylation level of P38 MAPK and TNF-α and IL-1β levels in lung lavage fluid (all P < 0.05). Treatment with JWH133 improved alveolar pathology in the septic rats, but there was still inflammatory infiltration; lung tissue water content, phosphorylation of P38 MAPK, and TNF-α and IL-1β levels in lung lavage fluid were all significantly decreased, and the fluid clearance rate, pulmonary expressions of CB2, occludin and ZO-1 were significantly increased (all P < 0.05). Additional treatment with SB203580 resulted in further improvements of alveolar pathologies, lowered phosphorylation levels of P38 MAPK in the lung tissue and TNF-α and IL-1β levels in lung lavage fluid, and increased the protein expressions of occludin and ZO-1 (P < 0.05) without causing significant changes in mRNA and protein expression of CB2 (P > 0.05).
CONCLUSION
In rats with LPS-induced sepsis, activation of CB2 can inhibit the p38 MAPK signaling pathway, reduce the release of inflammatory factors in the lung tissues, promote tight junction protein expressions, and thus offer protection against acute lung injury.
Acute Lung Injury/metabolism*
;
Animals
;
Cannabinoids
;
Lipopolysaccharides/adverse effects*
;
Lung/pathology*
;
Occludin/metabolism*
;
RNA, Messenger/metabolism*
;
Rats
;
Rats, Sprague-Dawley
;
Receptor, Cannabinoid, CB2
;
Receptors, Cannabinoid/metabolism*
;
Sepsis/metabolism*
;
Tumor Necrosis Factor-alpha/metabolism*
;
Water/metabolism*
;
p38 Mitogen-Activated Protein Kinases/metabolism*
6.The destructive role of soluble Robo4 secreted by the M1-polarized-microglia during cerebral ischemia-reperfusion in blood-brain barrier integrity.
Jin-Long HUANG ; Chen LI ; Liang-Liang YANG ; Yang GAO ; Pu-Yuan ZHAO ; Zhi-Gang YANG
Acta Physiologica Sinica 2022;74(4):513-524
This project was aimed to investigate the role and the underlying mechanism of microglia polarization on blood-brain barrier (BBB) during cerebral ischemia-reperfusion. After construction of the mouse model of cerebral ischemia-reperfusion, upregulated IL-6 and TNF-α in peripheral blood and increased IL-6 and iNOS in ischemia tissues were confirmed. The supernatant expression of TNF-α and IL-6, as well as IL-6, iNOS and CD86 mRNA, was significantly increased in the of Bv-2 cells after oxygen-glucose deprivation/reoxygenation (OGD/R) model was constructed in vitro. For further understanding the expression pattern of RNAs, the next-generation RNA sequencing was performed and upregulation of Robo4 (roundabout guidance receptor 4) was found both in M1-polarized and OGD/R treated Bv-2 cells, which was also confirmed by RT-qPCR. Extracellular soluble Robo4 (sRobo4) protein also increased in the supernatant of M1-polarized and OGD/R treated Bv-2 cells. Treating bEND3 cells with the Robo4 recombinant protein, M1-polarized Bv-2 cell supernatant or OGD/R Bv-2 cell supernatant decreased trans-endothelial electrical resistance (TEER), suggesting the injury of BBB. In addition, Robo4 was also highly expressed in the serum of patients who experienced acute ischemia stroke and mechanical thrombectomy operation. All the results suggest that increased secretion of Robo4 by M1-polarized-microglia during cerebral ischemia-reperfusion is most likely one of the causes of BBB injury, and Robo4 may be one of the therapeutic targets for BBB functional protection.
Animals
;
Blood-Brain Barrier/metabolism*
;
Brain Ischemia/drug therapy*
;
Glucose/metabolism*
;
Interleukin-6/metabolism*
;
Mice
;
Microglia/metabolism*
;
Oxygen/metabolism*
;
Receptors, Cell Surface/metabolism*
;
Reperfusion
;
Reperfusion Injury/drug therapy*
;
Tumor Necrosis Factor-alpha/metabolism*
7.Anti-herpes simplex virus type Ⅰ of tectorigenin derivative and effect on Toll-like receptors in vitro.
Yuan WANG ; Ming-Ming YUAN ; Jing ZHOU ; Xiao-Han ZHENG ; Chong-Jun YUAN ; Shuai CHEN ; Sen LUO ; Lei ZHANG
China Journal of Chinese Materia Medica 2022;47(16):4428-4435
The study investigated the inhibitory effect and mechanism of tectorigenin derivative(SGY) against herpes simplex virus type Ⅰ(HSV-1) by in vitro experiments. The cytotoxicity of SGY and positive drug acyclovir(ACV) on African green monkey kidney(Vero) cells and mouse microglia(BV-2) cells was detected by cell counting kit-8(CCK-8) method, and the maximum non-toxic concentration and median toxic concentration(TC_(50)) of the drugs were calculated. After Vero cells were infected with HSV-1, the virulence was determined by cytopathologic effects(CPE) to calculate viral titers. The inhibitory effect of the tested drugs on HSV-1-induced cytopathy in Vero cells was measured, and their modes of action were initially explored by virus adsorption, replication and inactivation. The effects of the drugs on viral load of BV-2 cells 24 h after HSV-1 infection and the Toll-like receptor(TLR) mRNA expression were detected by real-time fluorescence quantitative PCR(RT-qPCR). The maximum non-toxic concentrations of SGY against Vero and BV-2 cells were 382.804 μg·mL~(-1) and 251.78 μg·mL~(-1), respectively, and TC_(50) was 1 749.98 μg·mL~(-1) and 2 977.50 μg·mL~(-1), respectively. In Vero cell model, the half maximal inhibitory concentration(IC_(50)) of SGY against HSV-1 was 54.49 μg·mL~(-1), and the selection index(SI) was 32.12, with the mode of action of significantly inhibiting replication and directly inactivating HSV-1. RT-qPCR results showed that SGY markedly reduced the viral load in cells. The virus model group had significantly increased relative expression of TLR2, TLR3 and tumor necrosis factor receptor-associated factor 3(TRAF3) and reduced relative expression of TLR9 as compared with normal group, and after SGY intervention, the expression of TLR2, TLR3 and TRAF3 was decreased to different degrees and that of TLR9 was enhanced. The expression of inflammatory factors inducible nitric oxide synthase(iNOS), tumor necrosis factor-α(TNF-α), and interleukin-1β(IL-1β) was remarkably increased in virus model group as compared with that in normal group, and the levels of these inflammatory factors dropped after SGY intervention. In conclusion, SGY significantly inhibited and directly inactivated HSV-1 in vitro. In addition, it modulated the expression of TLR2, TLR3 and TLR9 related pathways, and suppressed the increase of inflammatory factor levels.
Animals
;
Antiviral Agents/therapeutic use*
;
Chlorocebus aethiops
;
Herpes Simplex/pathology*
;
Herpesvirus 1, Human/metabolism*
;
Isoflavones
;
Mice
;
TNF Receptor-Associated Factor 3/pharmacology*
;
Toll-Like Receptor 2/metabolism*
;
Toll-Like Receptor 3/metabolism*
;
Toll-Like Receptor 9/metabolism*
;
Toll-Like Receptors/metabolism*
;
Tumor Necrosis Factor-alpha/metabolism*
;
Vero Cells
;
Virus Replication
8.Bufalin Induces Programmed Necroptosis in Triple-Negative Breast Cancer Drug-Resistant Cell Lines through RIP1/ROS-Mediated Pathway.
Xiao-Dan LIU ; Cheng-Yang SONG ; Cui-Cui KONG ; Xin TIAN
Chinese journal of integrative medicine 2022;28(10):900-908
OBJECTIVE:
To explore the effect and mechanism of action of bufalin in triple-negative breast cancer (TNBC) drug-resistant cell lines.
METHODS:
The normal human mammary epithelial cell line, TNBC cell line, TNBC adriamycin-resistant cell line, and TNBC docetaxel-resistant cell line were treated with different doses of bufalin (0-1,000 nmol/L) at different time points (0-72 h). Propidium iodide staining, AV-FITC/PI double staining, Hoechst 33342/PI double staining and transmission electron microscopy (TEM) were used to evaluate the death patterns of the cell lines.
RESULTS:
Bufalin killed the TNBC cell line and its drug-resistant cell lines in a dose/time-dependent manner (all P<0.01). After treatment with bufalin for 24 h, the adriamycin-resistant cell line showed a co-existing pattern of necroptosis and apoptosis. However, at 48 h, necroptosis was the main manifestation. After treatment with bufalin, the expressions of tumor necrosis factor α, phospho-tumor necrosis factor receptor 1, phospho-receptor interacting protein 1 and c-caspase 3 increased (all P<0.01), the killing effect of bufalin could be mostly inhibited by NEC-1, and by z-VAD-fmk (both P<0.01). Besides, the intracellular reactive oxygen species (ROS) levels increased considerably (P<0.01), the antioxidant N-acetyl cysteine or Nec-1 could inhibit the increase of ROS level and the killing effect of bufalin (all P<0.01). The adriamycin-resistant cell line exhibited necroptosis characteristic after 48 h of bufalin treatment under TEM.
CONCLUSIONS
Bufalin could induce necroptosis through RIP1/ROS-mediated pathway to kill the drug-resistant TNBC cell lines. This finding provides critical experimental data and theoretical basis for the clinical application of bufalin to overcome the difficulties in the treatment of TNBC.
Antioxidants/pharmacology*
;
Apoptosis
;
Bufanolides
;
Caspase 3/metabolism*
;
Cell Line
;
Cell Line, Tumor
;
Cysteine/pharmacology*
;
Docetaxel/pharmacology*
;
Doxorubicin/pharmacology*
;
Fluorescein-5-isothiocyanate/pharmacology*
;
Humans
;
Necroptosis
;
Propidium/pharmacology*
;
Reactive Oxygen Species/metabolism*
;
Receptors, Tumor Necrosis Factor
;
Triple Negative Breast Neoplasms/drug therapy*
;
Tumor Necrosis Factor-alpha/pharmacology*
9.Effects of Different Inflammatory Factors on Hepatocyte Kinase Receptors and Ligands in Human Periodontal Ligament Fibroblasts.
Xiao Nan XU ; Meng Lin WANG ; Ding ZHANG
Acta Academiae Medicinae Sinicae 2019;41(3):300-306
Objective To investigate the effects of different inflammatory factors on hepatocyte kinase receptor(Eph)and ligand(ephrin)in human periodontal ligament fibroblasts(hPDLFs).Methods hPDLFs were stimulated with either 10 ng/ml tumor necrosis factor-α(TNF-α)or 10 ng/ml interleukin(IL)-1β,and then the expressions of Eph and ephrin at both mRNA and protein levels were determined at 0,1,2,6,12,and 24 hours.Results The levels of Eph receptors and ephrin ligand changed in a time-dependent manner in human periodontal ligament fibroblasts after treatment with TNF-α or IL-1β. The expression of ephrinA2 significantly increased in both groups within 24 hours(all <0.05). In the TNF-α group,the mRNA expression of ephrinA2 significantly increased at 1 h and was significant higher that in the IL-1β group at 24 h(<0.05). EphB4 showed a time-dependent decline after a short period of high expression.Conclusions Both TNF-α and IL-1β can cause changes in the expressions of Eph receptors and ephrin ligands in hPDLFs. The changes induced by both are consistent,although the effect of TNF-α is more pronounced.
Cells, Cultured
;
Ephrins
;
metabolism
;
Fibroblasts
;
Humans
;
Interleukin-1beta
;
pharmacology
;
Ligands
;
Periodontal Ligament
;
cytology
;
Receptors, Eph Family
;
metabolism
;
Tumor Necrosis Factor-alpha
;
pharmacology
10.TNF-α/TNFR1 Signaling is Required for the Full Expression of Acute and Chronic Itch in Mice via Peripheral and Central Mechanisms.
Xiuhua MIAO ; Ya HUANG ; Teng-Teng LIU ; Ran GUO ; Bing WANG ; Xue-Long WANG ; Li-Hua CHEN ; Yan ZHOU ; Ru-Rong JI ; Tong LIU
Neuroscience Bulletin 2018;34(1):42-53
Increasing evidence suggests that cytokines and chemokines play crucial roles in chronic itch. In the present study, we evaluated the roles of tumor necrosis factor-alpha (TNF-α) and its receptors TNF receptor subtype-1 (TNFR1) and TNFR2 in acute and chronic itch in mice. Compared to wild-type (WT) mice, TNFR1-knockout (TNFR1-KO) and TNFR1/R2 double-KO (DKO), but not TNFR2-KO mice, exhibited reduced acute itch induced by compound 48/80 and chloroquine (CQ). Application of the TNF-synthesis inhibitor thalidomide and the TNF-α antagonist etanercept dose-dependently suppressed acute itch. Intradermal injection of TNF-α was not sufficient to evoke scratching, but potentiated itch induced by compound 48/80, but not CQ. In addition, compound 48/80 induced TNF-α mRNA expression in the skin, while CQ induced its expression in the dorsal root ganglia (DRG) and spinal cord. Furthermore, chronic itch induced by dry skin was reduced by administration of thalidomide and etanercept and in TNFR1/R2 DKO mice. Dry skin induced TNF-α expression in the skin, DRG, and spinal cord and TNFR1 expression only in the spinal cord. Thus, our findings suggest that TNF-α/TNFR1 signaling is required for the full expression of acute and chronic itch via peripheral and central mechanisms, and targeting TNFR1 may be beneficial for chronic itch treatment.
Animals
;
Chloroquine
;
toxicity
;
Disease Models, Animal
;
Dose-Response Relationship, Drug
;
Etanercept
;
therapeutic use
;
Ganglia, Spinal
;
drug effects
;
metabolism
;
Male
;
Mice
;
Mice, Inbred C57BL
;
Mice, Transgenic
;
Pruritus
;
chemically induced
;
drug therapy
;
metabolism
;
pathology
;
RNA, Messenger
;
metabolism
;
Receptors, Tumor Necrosis Factor, Type I
;
deficiency
;
genetics
;
Receptors, Tumor Necrosis Factor, Type II
;
deficiency
;
genetics
;
Signal Transduction
;
drug effects
;
Skin
;
drug effects
;
metabolism
;
Spinal Cord
;
drug effects
;
metabolism
;
Thalidomide
;
therapeutic use
;
Time Factors
;
Tumor Necrosis Factor-alpha
;
adverse effects
;
genetics
;
metabolism
;
p-Methoxy-N-methylphenethylamine
;
toxicity

Result Analysis
Print
Save
E-mail