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 leukoc...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.展开更多
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 ...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.展开更多
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...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.展开更多
AIM: To determine the temporal expression and pattern of Rel/nuclear factor (NF)-κB proteins in renal tissue in polycystic kidney disease (PKD). METHODS: The renal expression of Rel/NF-κB proteins was determin...AIM: To determine the temporal expression and pattern of Rel/nuclear factor (NF)-κB proteins in renal tissue in polycystic kidney disease (PKD). METHODS: The renal expression of Rel/NF-κB proteins was determined by immunohistochemistry, immunofuorescence and immunoblot analysis in Lewis polycystic kidney rats (LPK, a genetic ortholog of human nephronopthsis-9) from postnatal weeks 3 to 20. At each timepoint, renal disease progression and the mRNA expression of NF-κB-dependent genes (TNFa and CCL2) were determined. NF-κB was also histologically assessed in human PKD tissue.RESULTS: Progressive kidney enlargement in LPK rats was accompanied by increased renal cell proliferation and interstitial monocyte accumulation (peaking at weeks 3 and 10 respectively), and progressive interstitial fibrosis (with a smooth muscle actin and Sirius Red deposition significantly increased compared to Lewis kidneys from weeks 3 to 6 onwards). Rel/NF-κB proteins (phosphorylated-p105, p65, p50, c-Rel and RelB) were expressed in cystic epithelial cells (CECs) of LPK kidneys as early as postnatal week 3 and sustained until late-stage disease at week 20. From weeks 10 to 20, nuclear p65, p50, RelB and cytoplasmic IκBa protein levels, and TNFa and CCL2 expression, were upregulated in LPK compared to Lewis kidneys. NF-κB proteins were consistently expressed in CECs of human PKD. The DNA damage marker γ-H2AX was also identifed in the CECs of LPK and human polycystic kidneys. CONCLUSION: Several NF-κB proteins are consistently expressed in CECs in human and experimental PKD. These data suggest that the upregulation of both the canonical and non-canonical pathways of NF-κB signaling may be a constitutive and early pathological feature of cystic renal diseases.展开更多
OBJECTIVE: To investigate the efficacy of the full composition granules of Huanglian(Rhizoma Coptidis)(FGC) on the serum monocyte chemotactic protein-1(MCP-1) and connective tissue growth factor(CTGF) levels and kidne...OBJECTIVE: To investigate the efficacy of the full composition granules of Huanglian(Rhizoma Coptidis)(FGC) on the serum monocyte chemotactic protein-1(MCP-1) and connective tissue growth factor(CTGF) levels and kidney nuclear factor-κB(NF-κB) expression in rats with high-fat diet-induced diabetes.METHODS: Diabetes was induced in rats by feeding a high-fat chow combined with intravenous streptozotocin injection. Forty diabetic SpragueDawley rats were randomly assigned to a normal group(NG), model group(MG), irbesartan group(IG), and low-, middle-, and high-dosage FGC groups(LFGC, MFGC, HFGC), with eight rats per group. The IG rats received 31.25 mg·kg^(-1)·d^(-1) irbesartan tablets, whereas those in the LFGC, MFGC,and HFGC were administered 52, 312.5, and 625 mg·kg^(-1)·d^(-1) FGC, respectively. After 12 weeks,bodyweight(BW), left kidney weight(KW), hemoglobin A1c(HbA1c), serum creatinine(Scre), blood urea nitrogen(BUN), and serum MCP-1 and CTGF levels were determined, pathological changes of the kidney were recorded, and kidney NF-κB p65(A) expression was measured.RESULTS: The 24-h urine albumin and levels of HbA1c, Scre, BUN, and serum MCP-1 and CTGF were significantly increased in in the MG compared with the NG, as was the kidney NF-κB(p65) expression(P < 0.05). Furthermore, clear pathological changes in kidney fibrosis were observed in the MG rats. Following irbesartan and FGC administration,the 24-h urine albumin and the levels of HbA1c,Scre, and serum MCP-1 and CTGF were significantly decreased in FCG groups compared with those in the MG, which is in agreement with the change in the kidney NF-κB(p65) expression, whereas the similarly significant decrease only exist in 24-h urine albumin and the levels of serum CTGF after irbesartan administration. Hematoxylin-eosin(HE)staining results indicated that the fibrosis observed in the MG samples was alleviated through FGC treatment.CONCLUSION: FGC may alleviate potential kidney injury by decreasing the serum MCP-1 and CTGF levels and inhibiting NF-k B expression in diabetic nephropathy in rats with high-fat diet-induced diabetes.展开更多
基金supported by the China Postdoctoral Science Foundation,No.2020M681689(to YMH)the Basic Scientific Research Projects of Nantong,Nos.JC2020015(to HX)and JC2020041(to YMH)。
文摘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.
基金supported by grants from the National Natural Science Foundation of China(31400949,81502102,31471059,81371498,and 31371121)NIH R01,USA Grants(DE17794,DE22743,and NS87988)
文摘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.
基金Supported by NHMRC Medical Postgraduate Scholarship and the Royal Brisbane and Women’s Hospital Research Foundation to Wood MJthe National Health and Medical Research Council(NHMRC)to Ramm GA and Powell LW+1 种基金the recipient of an NHMRC Senior Research Fellowship,1024672 to Subramaniam VNan NHMRC Senior Research Fellowship,No.552409 to Ramm GA
文摘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.
基金Supported by Funding from the National Health and Medical Research Council of Australia,Nos.457575 and 632647 to Rangan GKthe Baltimore Polycystic Kidney Disease Research and Clinical Core Center,No.P30DK090868+2 种基金DK095036 to Watnick Tsupported by an Australian Postgraduate Award(University of Sydney)the Michael Stern Polycystic Kidney Disease Research Fellowship
文摘AIM: To determine the temporal expression and pattern of Rel/nuclear factor (NF)-κB proteins in renal tissue in polycystic kidney disease (PKD). METHODS: The renal expression of Rel/NF-κB proteins was determined by immunohistochemistry, immunofuorescence and immunoblot analysis in Lewis polycystic kidney rats (LPK, a genetic ortholog of human nephronopthsis-9) from postnatal weeks 3 to 20. At each timepoint, renal disease progression and the mRNA expression of NF-κB-dependent genes (TNFa and CCL2) were determined. NF-κB was also histologically assessed in human PKD tissue.RESULTS: Progressive kidney enlargement in LPK rats was accompanied by increased renal cell proliferation and interstitial monocyte accumulation (peaking at weeks 3 and 10 respectively), and progressive interstitial fibrosis (with a smooth muscle actin and Sirius Red deposition significantly increased compared to Lewis kidneys from weeks 3 to 6 onwards). Rel/NF-κB proteins (phosphorylated-p105, p65, p50, c-Rel and RelB) were expressed in cystic epithelial cells (CECs) of LPK kidneys as early as postnatal week 3 and sustained until late-stage disease at week 20. From weeks 10 to 20, nuclear p65, p50, RelB and cytoplasmic IκBa protein levels, and TNFa and CCL2 expression, were upregulated in LPK compared to Lewis kidneys. NF-κB proteins were consistently expressed in CECs of human PKD. The DNA damage marker γ-H2AX was also identifed in the CECs of LPK and human polycystic kidneys. CONCLUSION: Several NF-κB proteins are consistently expressed in CECs in human and experimental PKD. These data suggest that the upregulation of both the canonical and non-canonical pathways of NF-κB signaling may be a constitutive and early pathological feature of cystic renal diseases.
基金Supported by Beijing Traditional Chinese Medicine Science and Technology Project:Study on the Mechanism of High Dose Huanglian (Rhizoma Coptidis) in Treating Diabetic Nephropathy (No.QN2014-08)。
文摘OBJECTIVE: To investigate the efficacy of the full composition granules of Huanglian(Rhizoma Coptidis)(FGC) on the serum monocyte chemotactic protein-1(MCP-1) and connective tissue growth factor(CTGF) levels and kidney nuclear factor-κB(NF-κB) expression in rats with high-fat diet-induced diabetes.METHODS: Diabetes was induced in rats by feeding a high-fat chow combined with intravenous streptozotocin injection. Forty diabetic SpragueDawley rats were randomly assigned to a normal group(NG), model group(MG), irbesartan group(IG), and low-, middle-, and high-dosage FGC groups(LFGC, MFGC, HFGC), with eight rats per group. The IG rats received 31.25 mg·kg^(-1)·d^(-1) irbesartan tablets, whereas those in the LFGC, MFGC,and HFGC were administered 52, 312.5, and 625 mg·kg^(-1)·d^(-1) FGC, respectively. After 12 weeks,bodyweight(BW), left kidney weight(KW), hemoglobin A1c(HbA1c), serum creatinine(Scre), blood urea nitrogen(BUN), and serum MCP-1 and CTGF levels were determined, pathological changes of the kidney were recorded, and kidney NF-κB p65(A) expression was measured.RESULTS: The 24-h urine albumin and levels of HbA1c, Scre, BUN, and serum MCP-1 and CTGF were significantly increased in in the MG compared with the NG, as was the kidney NF-κB(p65) expression(P < 0.05). Furthermore, clear pathological changes in kidney fibrosis were observed in the MG rats. Following irbesartan and FGC administration,the 24-h urine albumin and the levels of HbA1c,Scre, and serum MCP-1 and CTGF were significantly decreased in FCG groups compared with those in the MG, which is in agreement with the change in the kidney NF-κB(p65) expression, whereas the similarly significant decrease only exist in 24-h urine albumin and the levels of serum CTGF after irbesartan administration. Hematoxylin-eosin(HE)staining results indicated that the fibrosis observed in the MG samples was alleviated through FGC treatment.CONCLUSION: FGC may alleviate potential kidney injury by decreasing the serum MCP-1 and CTGF levels and inhibiting NF-k B expression in diabetic nephropathy in rats with high-fat diet-induced diabetes.