1.Effects of rapamycin on activation of NLRP3 inflammasome induced by MPP+ in microglia
Shuxuan HUANG ; Huanhuan LU ; Binglin FAN ; Zhi CHEN ; Bingjian JIANG ; Yuejuan WU ; Xiaofeng LI ; Yanhua LI
Chinese Journal of Behavioral Medicine and Brain Science 2020;29(9):774-779
Objective:To explore the effect of rapamycin on 1-methyl-4-phenylpyridinium iodide (MPP+ )-induced activation of Nod-like receptor protein 3 (NLRP3) inflammasome in microglia.Methods:The BV2 microglia cells were divided into control group, model group and rapamycin group.The model group and rapamycin group were treated by MPP+ to activate NLRP3 inflammasome, and rapamycin group was pretreated with rapamycin.Quantitative real-time PCR (RT-qPCR) was used to detect the mRNA levels of NLRP3, apoptosis-associated speck-like protein (ASC) and caspase-1.Immunofluorescence was used to detect the protein expression of NLRP3 and interleukin-1β (IL-1β). Western blot was carried out to assess the protein expression of NLRP3, ASC, caspase-1, beclin1 and microtubule-associated protein 1 light chain 3 (LC3).Results:The mRNA levels of NLRP3, ASC and caspase-1 in model group were higher than those in control group ( t=4.825, 3.015, 5.853, all P<0.05). The mRNA levels of NLRP3 and caspase-1 in rapamycin group were lower than those in model group ( t=2.75, 2.89, both P<0.05). In model group, the protein expressions of NLRP3 (1.54±0.22), ASC (1.02±0.13) and caspase-1 (1.42±0.30) were higher than NLRP3 (0.66±0.15), ASC (0.41±0.14) and caspase-1 (0.70±0.10) in control group ( t=5.653, 5.602, 3.964, all P<0.01), while the protein expression of beclin1 (0.28±0.09) and LC3II/LC3I ratio(0.69±0.14) were lower than beclin1 (0.60±0.11) and LC3II/LC3I (1.29±0.23) in control group ( t=4.010, 3.982, both P<0.01). The protein expressions of NLRP3 (0.80±0.18) and ASC (0.68±0.14) in rapamycin group were lower than those in model group ( t=4.413, 3.077, both P<0.05), while the protein expression of beclin1 (0.65±0.20) and LC3II/LC3I ratio(1.42±0.36) were higher than those in model group ( t=2.965, 3.278, both P<0.05). Conclusion:MPP+ activates NLRP3 inflammasome and impairs autophagic function in microglia.Rapamycin inhibits MPP+ -induced activation of NLRP3 inflammasome by restoring autophagic impairment in microglia.
2.PTEN and NBS1 gene mutations in familial breast cancer and early-onset breast cancer from Hunan Province in China.
Yuhui WU ; Bingjian JIANG ; Xu DAI ; Xueli HU ; Shouman WANG ; Pinglan JIANG ; Yuanping HU ; Jun HUANG
Journal of Central South University(Medical Sciences) 2016;41(2):121-126
OBJECTIVE:
To investigate the profile and potential significance of PTEN and NBS1 mutations among patients with familial or at early onset breast cancer in Hunan province.
METHODS:
A total of 131 breast cancer patients with familial history or suffered from breast cancer at the age of less than 35 years old were included in this study. A comprehensive phosphatase and tensin homolog (PTEN) and nibrin (NBS1) mutation analysis was performed through denaturing high performance liquid chromatography (DHPLC) and subsequent DNA direct sequencing.
RESULTS:
Among 131 patients, a reported mutation IVS4+109insTCTTA in PTEN gene were identified in two patients. The mutation frequency of IVS4+109insTCTTA was 1.15%. Two mutations in PTEN gene, 225 A>C (Thr 160 Pro) and IVS5+13T>C, was firstly discovered. Another reported missense mutation was rs121909229 G>A (Arg 130 Gln). Three mutations were detected in NBS1 gene, of which IVS6+43A>G and IVS6+127A>G were firstly discovered and another reported synonymous mutations was rs1805794 G>C (Glu 185 Gln).
CONCLUSION
The novel mutations in PTEN and NBS1 might be specific to the familial and early-onset breast cancer of Chinese Hunan population.
Adult
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Asian Continental Ancestry Group
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Breast Neoplasms
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genetics
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Cell Cycle Proteins
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genetics
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China
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DNA Mutational Analysis
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Female
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Humans
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Mutation
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Nuclear Proteins
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genetics
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PTEN Phosphohydrolase
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genetics
3.Autophagy enhanced by curcumin ameliorates inflammation in atherogenesis via the TFEB-P300-BRD4 axis.
Xuesong LI ; Ruigong ZHU ; Hong JIANG ; Quanwen YIN ; Jiaming GU ; Jiajing CHEN ; Xian JI ; Xuan WU ; Haiping FU ; Hui WANG ; Xin TANG ; Yuanqing GAO ; Bingjian WANG ; Yong JI ; Hongshan CHEN
Acta Pharmaceutica Sinica B 2022;12(5):2280-2299
Disturbance of macrophage-associated lipid metabolism plays a key role in atherosclerosis. Crosstalk between autophagy deficiency and inflammation response in foam cells (FCs) through epigenetic regulation is still poorly understood. Here, we demonstrate that in macrophages, oxidized low-density lipoprotein (ox-LDL) leads to abnormal crosstalk between autophagy and inflammation, thereby causing aberrant lipid metabolism mediated through a dysfunctional transcription factor EB (TFEB)-P300-bromodomain-containing protein 4 (BRD4) axis. ox-LDL led to macrophage autophagy deficiency along with TFEB cytoplasmic accumulation and increased reactive oxygen species generation. This activated P300 promoted BRD4 binding on the promoter regions of inflammatory genes, consequently contributing to inflammation with atherogenesis. Particularly, ox-LDL activated BRD4-dependent super-enhancer associated with liquid-liquid phase separation (LLPS) on the regulatory regions of inflammatory genes. Curcumin (Cur) prominently restored FCs autophagy by promoting TFEB nuclear translocation, optimizing lipid catabolism, and reducing inflammation. The consequences of P300 and BRD4 on super-enhancer formation and inflammatory response in FCs could be prevented by Cur. Furthermore, the anti-atherogenesis effect of Cur was inhibited by macrophage-specific Brd4 overexpression or Tfeb knock-out in Apoe knock-out mice via bone marrow transplantation. The findings identify a novel TFEB-P300-BRD4 axis and establish a new epigenetic paradigm by which Cur regulates autophagy, inhibits inflammation, and decreases lipid content.