Alzheimer’s, characterized by β-amyloid accumulation and tau hyperphosphorylation, is linked to inflammation, oxidative stress, and microglial activation, suggesting potential protective strategies. Studies have sho...Alzheimer’s, characterized by β-amyloid accumulation and tau hyperphosphorylation, is linked to inflammation, oxidative stress, and microglial activation, suggesting potential protective strategies. Studies have shown that natural polyphenolic anthocyanin components found in berries, such as cyanidin, can inhibit amyloid filament formation and modulate Alzheimer’s disease are polyphenolic flavonoids, which are responsible for red, purple, and blue colors in various fruits, such as red cabbage and most berries. Here, we reviewed the protective effects of anthocyanins. It has anti-inflammatory and antioxidant properties, reduces NF-κB, and affects inflammatory signaling pathways. They also improve cognitive function, making them a potential protective strategy against AD.展开更多
Endothelial activation by proinflammatory cytokines is closely associated to the pathogenesis of atherosclerosis and other vascular diseases;however, the molecular mechanisms controlling endothelial activation are not...Endothelial activation by proinflammatory cytokines is closely associated to the pathogenesis of atherosclerosis and other vascular diseases;however, the molecular mechanisms controlling endothelial activation are not fully understood. Here we identify TRIM14 as a new positive regulator of endothelial activation via activating NF-κB signal pathway. TRIM14 is highly expressed in human vascular endothelial cells (ECs) and markedly induced by inflammatory stimuli such as TNF-α, IL-1β, and LPS. Overexpression of TRIM14 significantly increased the expression of adhesion molecules such as VCAM-1, ICAM-1, E-selectin, and cytokines such as CCL2, IL-8, CXCL-1, and TNF-α in activated ECs and by which it facilitated monocyte adhesion to ECs. Conversely, knockdown of TRIM14 has opposite effect on endothelial activation. Upon TNF-α stimulation, TRIM14 is recruited to IKK complex via directly binding to NEMO and promotes the phosphorylation of IκBα and p65, which is dependent on its K63-linked ubiquitination. Meanwhile, p65 can directly bind to the promoter regions of human TRIM14 gene and control its mRNA transcription. Finally, TRIM14 protein level is significantly upregulated in mouse and human atheroma compared to normal arteries. Taken together, these results indicate that TRIM14-NF-κB forms a positive feedback loop to enhance EC activation and TRIM14 may be a potential therapeutic target for vascular inflammatory diseases such as atherosclerosis.展开更多
NF-κB signaling controls a large set of physiological processes ranging from inflammatory responses to cell death. Its activation is tightly regulated through controlling the activity and stability of multiple signal...NF-κB signaling controls a large set of physiological processes ranging from inflammatory responses to cell death. Its activation is tightly regulated through controlling the activity and stability of multiple signaling components. Here, we identify that NF-κB activation is suppressed by an F-box protein, S-phase kinase associated protein 2 （SKP2）. SKP2 deficiency enhanced NF-κB activation as well as the production of inflammatory cytokines. In addition, SKP2 potently blocked the NF-κB activation at the κB kinase （IKIO level. Mechanistic study further revealed that SKP2 functions as an adaptor to promote an interaction between active IKKβ and the autophagic cargo receptor p62 to mediate IKKβ degradation via selective autophasy. These findings identify a previously unrecognized role of SKP2 in NF-κB activation by which SKP2 acts as a secondary receptor to assist IKKβ delivery to autophagosomes for degradation in a p62-dependent manner.展开更多
Background:Gram-positive bacteria stimulate Toll-like receptor(TLR)2 and then activate the pro-inflammatory nuclear factor-kappa B(NF-κB)pathway.As the human ocular surface is heavily colonised by gram-positive cocci...Background:Gram-positive bacteria stimulate Toll-like receptor(TLR)2 and then activate the pro-inflammatory nuclear factor-kappa B(NF-κB)pathway.As the human ocular surface is heavily colonised by gram-positive cocci bacteria,a balance of activation/repression of NF-κB target genes is essential to avoid uncontrolled infection or autoimmune-related inflammation.It is advantageous to test NF-κB targeting molecules in an ocular surface culture system that allows assessment of temporal NF-κB activation in a longitudinal fashion without destruction of cells.Such initial testing under standardised conditions should reduce the number of molecules that progress to further evaluation in animal models.This study aims to establish an in-vitro cell culture system to assess NF-κB activation in the context of ocular surface cells.Methods:NF-κB activity was evaluated through a secretory alkaline phosphatase reporter assay(SEAP).Immunoblots and immunofluorescence were used to examine IκBαphosphorylation and p65/p50 nuclear localization.Monocyte chemoattractant protein-1(MCP-1)transcripts were evaluated by real time PCR and protein levels were measured by ELISA.Results:NF-κB activity in HCE-T cells treated with TLR2 activator Pam3CSK4 was higher than control cells at both 6 and 24 h.Pam3CSK4-stimulated NF-κB activation was inhibited by IκK inhibitors,Wedelolactone and BMS-345541.In Pam3CSK4 treated cells,active NF-κB subunits p50 and p65 increased in cell nuclear fractions as early as 1.5 h.Although the level of total IκB-αremained constant,phospho-IκB-αincreased with treatment over time.In the culture media of Pam3CSK4-stimulated cells,MCP-1 protein level was increased,which was suppressed in the presence of IκK inhibitors.Conclusion:NF-κB pathway can be activated by the TLR2 ligand and inhibited by IκK inhibitors in the ocular surface cell culture system.This cell culture system may be used to evaluate TLR-related innate defences in ocular surface diseases.展开更多
The mesencephalic astrocyte-derived neurotrophic factor(MANF)has been recently identified as a neurotrophic factor,but its role in hepatic fibrosis is unknown.Here,we found that MANF was upregulated in the fibrotic li...The mesencephalic astrocyte-derived neurotrophic factor(MANF)has been recently identified as a neurotrophic factor,but its role in hepatic fibrosis is unknown.Here,we found that MANF was upregulated in the fibrotic liver tissues of the patients with chronic liver diseases and of mice treated with CCl4.MANF deficiency in either hepatocytes or hepatic mono-macrophages,particularly in hepatic mono-macrophages,clearly exacerbated hepatic fibrosis.Myeloid-specific MANF knockout increased the population of hepatic Ly6C^(high)macrophages and promoted HSCs activation.Furthermore,MANF-sufficient macrophages(from WT mice)transfusion ameliorated CCl4-induced hepatic fibrosis in myeloid cells-specific MANF knockout(MKO)mice.Mechanistically,MANF interacted with S100A8 to competitively block S100A8/A9 heterodimer formation and inhibited S100A8/A9-mediated TLR4-NF-κB signal activation.Pharmacologically,systemic administration of recombinant human MANF significantly alleviated CCl_(4)-induced hepatic fibrosis in both WT and hepatocytes-specific MANF knockout(HKO)mice.This study reveals a mechanism by which MANF targets S100A8/A9-TLR4 as a“brake”on the upstream of NF-κB pathway,which exerts an impact on macrophage differentiation and shed light on hepatic fibrosis treatment.展开更多
文摘Alzheimer’s, characterized by β-amyloid accumulation and tau hyperphosphorylation, is linked to inflammation, oxidative stress, and microglial activation, suggesting potential protective strategies. Studies have shown that natural polyphenolic anthocyanin components found in berries, such as cyanidin, can inhibit amyloid filament formation and modulate Alzheimer’s disease are polyphenolic flavonoids, which are responsible for red, purple, and blue colors in various fruits, such as red cabbage and most berries. Here, we reviewed the protective effects of anthocyanins. It has anti-inflammatory and antioxidant properties, reduces NF-κB, and affects inflammatory signaling pathways. They also improve cognitive function, making them a potential protective strategy against AD.
基金supported by The National Natural Science Foundation of China(81660390,31760329,and 81301964)M.F.was supported by American Heart Association(17AIREA33660073)and NIH Grant(AI103618)。
文摘Endothelial activation by proinflammatory cytokines is closely associated to the pathogenesis of atherosclerosis and other vascular diseases;however, the molecular mechanisms controlling endothelial activation are not fully understood. Here we identify TRIM14 as a new positive regulator of endothelial activation via activating NF-κB signal pathway. TRIM14 is highly expressed in human vascular endothelial cells (ECs) and markedly induced by inflammatory stimuli such as TNF-α, IL-1β, and LPS. Overexpression of TRIM14 significantly increased the expression of adhesion molecules such as VCAM-1, ICAM-1, E-selectin, and cytokines such as CCL2, IL-8, CXCL-1, and TNF-α in activated ECs and by which it facilitated monocyte adhesion to ECs. Conversely, knockdown of TRIM14 has opposite effect on endothelial activation. Upon TNF-α stimulation, TRIM14 is recruited to IKK complex via directly binding to NEMO and promotes the phosphorylation of IκBα and p65, which is dependent on its K63-linked ubiquitination. Meanwhile, p65 can directly bind to the promoter regions of human TRIM14 gene and control its mRNA transcription. Finally, TRIM14 protein level is significantly upregulated in mouse and human atheroma compared to normal arteries. Taken together, these results indicate that TRIM14-NF-κB forms a positive feedback loop to enhance EC activation and TRIM14 may be a potential therapeutic target for vascular inflammatory diseases such as atherosclerosis.
基金This work was supported by grants from the National Natural Science Foundation of China （91629101, 31522018, 31601135, 81302197, 81700557, and 31071046）, the National Key Basic Research Program of China （2015CB859800 and 2014CB910800）, and the 6uangdong Innovative Research Team Program （2011Y035）.
文摘NF-κB signaling controls a large set of physiological processes ranging from inflammatory responses to cell death. Its activation is tightly regulated through controlling the activity and stability of multiple signaling components. Here, we identify that NF-κB activation is suppressed by an F-box protein, S-phase kinase associated protein 2 （SKP2）. SKP2 deficiency enhanced NF-κB activation as well as the production of inflammatory cytokines. In addition, SKP2 potently blocked the NF-κB activation at the κB kinase （IKIO level. Mechanistic study further revealed that SKP2 functions as an adaptor to promote an interaction between active IKKβ and the autophagic cargo receptor p62 to mediate IKKβ degradation via selective autophasy. These findings identify a previously unrecognized role of SKP2 in NF-κB activation by which SKP2 acts as a secondary receptor to assist IKKβ delivery to autophagosomes for degradation in a p62-dependent manner.
基金supported by the Singapore National Research Foundation(NMRC/CSA/045/2012)administered by the Singapore Ministry of Health’s National Medical Research Council.
文摘Background:Gram-positive bacteria stimulate Toll-like receptor(TLR)2 and then activate the pro-inflammatory nuclear factor-kappa B(NF-κB)pathway.As the human ocular surface is heavily colonised by gram-positive cocci bacteria,a balance of activation/repression of NF-κB target genes is essential to avoid uncontrolled infection or autoimmune-related inflammation.It is advantageous to test NF-κB targeting molecules in an ocular surface culture system that allows assessment of temporal NF-κB activation in a longitudinal fashion without destruction of cells.Such initial testing under standardised conditions should reduce the number of molecules that progress to further evaluation in animal models.This study aims to establish an in-vitro cell culture system to assess NF-κB activation in the context of ocular surface cells.Methods:NF-κB activity was evaluated through a secretory alkaline phosphatase reporter assay(SEAP).Immunoblots and immunofluorescence were used to examine IκBαphosphorylation and p65/p50 nuclear localization.Monocyte chemoattractant protein-1(MCP-1)transcripts were evaluated by real time PCR and protein levels were measured by ELISA.Results:NF-κB activity in HCE-T cells treated with TLR2 activator Pam3CSK4 was higher than control cells at both 6 and 24 h.Pam3CSK4-stimulated NF-κB activation was inhibited by IκK inhibitors,Wedelolactone and BMS-345541.In Pam3CSK4 treated cells,active NF-κB subunits p50 and p65 increased in cell nuclear fractions as early as 1.5 h.Although the level of total IκB-αremained constant,phospho-IκB-αincreased with treatment over time.In the culture media of Pam3CSK4-stimulated cells,MCP-1 protein level was increased,which was suppressed in the presence of IκK inhibitors.Conclusion:NF-κB pathway can be activated by the TLR2 ligand and inhibited by IκK inhibitors in the ocular surface cell culture system.This cell culture system may be used to evaluate TLR-related innate defences in ocular surface diseases.
基金supported by the National Natural Science Foundation of China(81973336)the Joint Fund of the National Natural Science Foundation of China(U21A20345)。
文摘The mesencephalic astrocyte-derived neurotrophic factor(MANF)has been recently identified as a neurotrophic factor,but its role in hepatic fibrosis is unknown.Here,we found that MANF was upregulated in the fibrotic liver tissues of the patients with chronic liver diseases and of mice treated with CCl4.MANF deficiency in either hepatocytes or hepatic mono-macrophages,particularly in hepatic mono-macrophages,clearly exacerbated hepatic fibrosis.Myeloid-specific MANF knockout increased the population of hepatic Ly6C^(high)macrophages and promoted HSCs activation.Furthermore,MANF-sufficient macrophages(from WT mice)transfusion ameliorated CCl4-induced hepatic fibrosis in myeloid cells-specific MANF knockout(MKO)mice.Mechanistically,MANF interacted with S100A8 to competitively block S100A8/A9 heterodimer formation and inhibited S100A8/A9-mediated TLR4-NF-κB signal activation.Pharmacologically,systemic administration of recombinant human MANF significantly alleviated CCl_(4)-induced hepatic fibrosis in both WT and hepatocytes-specific MANF knockout(HKO)mice.This study reveals a mechanism by which MANF targets S100A8/A9-TLR4 as a“brake”on the upstream of NF-κB pathway,which exerts an impact on macrophage differentiation and shed light on hepatic fibrosis treatment.
