Pyroptosis is a pro-inflammatory form of regulated cell death and is dependent on the enzymatic activity of inflammatory proteases that belong to the family of cysteine-dependent aspartate-specific ...proteases (caspases). Pyroptosis is morphologically, mechanistically, and pathophysiologically distinct from other forms of cell death, including apoptosis and necrosis. Pyroptosis is characterized by rapid plasma membrane rupture, with the consequent release of intracellular contents and pro-inflammatory mediators, including interleukin (IL)-1β, IL-18, and the alarmin HMGB-1.Recent studies have shown that pyroptosis may be involved in atherosclerosis and play an important role in atherosclerotic lesion instability. Here, we review the progress made in understanding the morphological, molecular, and pathophysiological mechanisms of pyroptosis and its potential role in atherosclerosis.
Atherosclerosis is a progressive, chronic inflammation in arterial walls. Long noncoding RNAs (lncRNAs) participate in inflammation, but the exact mechanism in atherosclerosis is unclear. Our ...microarray analyses revealed that the levels of lncRNA-FA2H-2 were significantly decreased by oxidized low-density lipoprotein (OX-LDL). Bioinformatics analyses indicated that mixed lineage kinase domain-like protein (MLKL) might be regulated by lncRNA-FA2H-2. In vitro experiments showed that lncRNA-FA2H-2 interacted with the promoter of the MLKL gene, downregulated MLKL expression, and the binding sites between -750 and 471 were necessary for lncRNA-FA2H-2 responsiveness to MLKL. Silencing lncRNA-FA2H-2 and overexpression of MLKL could activate inflammation and inhibited autophagy flux. Both lncRNA-FA2H-2 knockdown and overexpression of MLKL could significantly aggravate inflammatory responses induced by OX-LDL. We found that the 3-methyladenine (3-MA) and Atg7-shRNA enhanced inflammatory responses induced by knockdown of lncRNA-FA2H-2 and overexpression of MLKL. We demonstrated that the effects of MLKL on autophagy might be associated with a mechanistic target of rapamycin (mTOR)-dependent signaling pathways. In vivo experiments with apoE knockout mice fed a western diet demonstrated that LncRNA-FA2H-2 knockdown decreased microtubule-associated expression of microtubule-associated protein 1 light chain 3 II and lysosome-associated membrane protein 1, but increased expression of sequestosome 1 (p62), MLKL, vascular cell adhesion molecule-1, monocyte chemoattractant protein-1, and interleukin-6 in atherosclerotic lesions. Our findings indicated that the lncRNA-FA2H-2-MLKL pathway is essential for regulation of autophagy and inflammation, and suggested that lncRNA-FA2H-2 and MLKL could act as potential therapeutic targets to ameliorate atherosclerosis-related diseases.
Nucleic acids from bacteria or viruses induce potent immune responses in infected cells
. The detection of pathogen-derived nucleic acids is a central strategy by which the host senses infection and ...initiates protective immune responses
. Cyclic GMP-AMP synthase (cGAS) is a double-stranded DNA sensor
. It catalyses the synthesis of cyclic GMP-AMP (cGAMP)
, which stimulates the induction of type I interferons through the STING-TBK1-IRF-3 signalling axis
. STING oligomerizes after binding of cGAMP, leading to the recruitment and activation of the TBK1 kinase
. The IRF-3 transcription factor is then recruited to the signalling complex and activated by TBK1
. Phosphorylated IRF-3 translocates to the nucleus and initiates the expression of type I interferons
. However, the precise mechanisms that govern activation of STING by cGAMP and subsequent activation of TBK1 by STING remain unclear. Here we show that a conserved PLPLRT/SD motif within the C-terminal tail of STING mediates the recruitment and activation of TBK1. Crystal structures of TBK1 bound to STING reveal that the PLPLRT/SD motif binds to the dimer interface of TBK1. Cell-based studies confirm that the direct interaction between TBK1 and STING is essential for induction of IFNβ after cGAMP stimulation. Moreover, we show that full-length STING oligomerizes after it binds cGAMP, and highlight this as an essential step in the activation of STING-mediated signalling. These findings provide a structural basis for the development of STING agonists and antagonists for the treatment of cancer and autoimmune disorders.
The clinical features and immune responses of asymptomatic individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have not been well described. We studied 37 ...asymptomatic individuals in the Wanzhou District who were diagnosed with RT-PCR-confirmed SARS-CoV-2 infections but without any relevant clinical symptoms in the preceding 14 d and during hospitalization. Asymptomatic individuals were admitted to the government-designated Wanzhou People's Hospital for centralized isolation in accordance with policy
. The median duration of viral shedding in the asymptomatic group was 19 d (interquartile range (IQR), 15-26 d). The asymptomatic group had a significantly longer duration of viral shedding than the symptomatic group (log-rank P = 0.028). The virus-specific IgG levels in the asymptomatic group (median S/CO, 3.4; IQR, 1.6-10.7) were significantly lower (P = 0.005) relative to the symptomatic group (median S/CO, 20.5; IQR, 5.8-38.2) in the acute phase. Of asymptomatic individuals, 93.3% (28/30) and 81.1% (30/37) had reduction in IgG and neutralizing antibody levels, respectively, during the early convalescent phase, as compared to 96.8% (30/31) and 62.2% (23/37) of symptomatic patients. Forty percent of asymptomatic individuals became seronegative and 12.9% of the symptomatic group became negative for IgG in the early convalescent phase. In addition, asymptomatic individuals exhibited lower levels of 18 pro- and anti-inflammatory cytokines. These data suggest that asymptomatic individuals had a weaker immune response to SARS-CoV-2 infection. The reduction in IgG and neutralizing antibody levels in the early convalescent phase might have implications for immunity strategy and serological surveys.
The ability to engineer genomes in a specific, systematic, and cost-effective way is critical for functional genomic studies. Recent advances using the CRISPR-associated single-guide RNA system ...(Cas9/sgRNA) illustrate the potential of this simple system for genome engineering in a number of organisms. Here we report an effective and inexpensive method for genome DNA editing in Drosophila melanogaster whereby plasmid DNAs encoding short sgRNAs under the control of the U6b promoter are injected into transgenic flies in which Cas9 is specifically expressed in the germ line via the nanos promoter. We evaluate the off-targets associated with the method and establish a Web-based resource, along with a searchable, genome-wide database of predicted sgRNAs appropriate for genome engineering in flies. Finally, we discuss the advantages of our method in comparison with other recently published approaches.
Atherosclerosis is a complex inflammatory disease that involves disrupted cellular cholesterol levels and formation of foam cells. Studies about long noncoding RNA (lncRNA) have revealed its function ...in the development of atherosclerosis, by mediating reverse cholesterol transport and formation of foam cells. In this study, we found that oxidized low‐density lipoprotein (ox‐LDL) markedly decreased lncRNA AC096664.3 in vascular smooth muscle cells (VSMCs) and THP‐1 macrophages. We also found that ox‐LDL reduced ATP‐binding cassette (ABC) G1 through inhibiting lncRNA AC096664.3 in VSMCs. Further experiments showed that the downregulation of lncRNA AC096664.3 reduced ABCG1 expression through inhibiting the expression of peroxisome proliferator–activated receptor‐γ (PPAR‐γ) and that ox‐LDL reduced ABCG1 expression through inhibiting the expression of PPAR‐γ. Furthermore, we discovered that ox‐LDL inhibited ABCG1 via the lncRNA AC096664.3/PPAR‐γ/ABCG1 pathway, which led to an increase in total and free cholesterol in VMSCs. Thus, we confirmed that ox‐LDL induces cholesterol accumulation via the lncRNA AC096664.3/PPAR‐γ/ABCG1 pathway in VSMCs, indicating a promising novel therapy in protecting against atherosclerosis.
Atherosclerosis is a complex inflammatory disease that involves disrupted cellular cholesterol level and formation of foam cells. Studies about long noncoding RNA (lncRNA) reveal its function in the development of atherosclerosis by mediating reverse cholesterol transport and the formation of foam cells. In this study, we confirmed that oxidized low‐density lipoprotein could induce cholesterol accumulation via the lncRNA AC096664.3/peroxisome proliferator–activated receptor‐γ/ATP‐binding cassette G1 pathway in vascular smooth muscle cells, indicating a promising novel therapy in protecting against atherosclerosis.
Skin wound therapy aims not only to restore skin protection but also to recover excitation functions through nerve regeneration. During the restoration of skin nerves, the recruitment of endogenous ...stem cells and promotion of neuronal regeneration on site work stepwise are foundations of in situ regeneration. However, current therapeutic systems usually execute each process separately, leading to limited regeneration and recovery of excitation functions. Herein, a novel self‐adaptive all‐in‐one delivery chip (G:P:Al‐Chip) is constructed that combines therapeutic protein release, gene delivery, and electrical conduction in a single microfluidic chip by 3D coaxial printing. G:P:Al‐Chip consists of an outer conductive hydrogel shell anchored with chemokine and an inner microchannel filled with enzyme‐initiated vector/plasmid DNAs microcomplexes. G:P:Al‐Chip delivers chemokine, functional plasmid DNAs, and promotes electrical conduction with a self‐adaptive program that significantly enhances the recruitment of endogenous mesenchymal stem cells and promotes neuronal regeneration. G:P:Al‐Chip is shown to enhance nerve regeneration with excitation functions within 23 days. G:P:Al‐Chip organizes recruitment and neuronal regeneration cues along with bioelectrical signal in one degradable chip for accelerated skin nerve regeneration.
An all‐in‐one delivery chip that combines protein release, gene delivery, and electrical conduction in a single microfluidic chip is developed via 3D coaxial printing. This chip organizes recruitment and neuronal regeneration cues for endogenous mesenchymal stem cells for in situ neuronal regeneration, providing a bottom‐up approach to regenerative biology.
Zingiber montanum (Z. montanum) and Zingiber zerumbet (Z. zerumbet) are important medicinal and ornamental herbs in the genus Zingiber and family Zingiberaceae. Chloroplast-derived markers are useful ...for species identification and phylogenetic studies, but further development is warranted for these two Zingiber species. In this study, we report the complete chloroplast genomes of Z. montanum and Z. zerumbet, which had lengths of 164,464 bp and 163,589 bp, respectively. These genomes had typical quadripartite structures with a large single copy (LSC, 87,856-89,161 bp), a small single copy (SSC, 15,803-15,642 bp), and a pair of inverted repeats (IRa and IRb, 29,393-30,449 bp). We identified 111 unique genes in each chloroplast genome, including 79 protein-coding genes, 28 tRNAs and 4 rRNA genes. We analyzed the molecular structures, gene information, amino acid frequencies, codon usage patterns, RNA editing sites, simple sequence repeats (SSRs) and long repeats from the two chloroplast genomes. A comparison of the Z. montanum and Z. zerumbet chloroplast genomes detected 489 single-nucleotide polymorphisms (SNPs) and 172 insertions/deletions (indels). Thirteen highly divergent regions, including ycf1, rps19, rps18-rpl20, accD-psaI, psaC-ndhE, psbA-trnK-UUU, trnfM-CAU-rps14, trnE-UUC-trnT-UGU, ccsA-ndhD, psbC-trnS-UGA, start-psbA, petA-psbJ, and rbcL-accD, were identified and might be useful for future species identification and phylogeny in the genus Zingiber. Positive selection was observed for ATP synthase (atpA and atpB), RNA polymerase (rpoA), small subunit ribosomal protein (rps3) and other protein-coding genes (accD, clpP, ycf1, and ycf2) based on the Ka/Ks ratios. Additionally, chloroplast SNP-based phylogeny analyses found that Zingiber was a monophyletic sister branch to Kaempferia and that chloroplast SNPs could be used to identify Zingiber species. The genome resources in our study provide valuable information for the identification and phylogenetic analysis of the genus Zingiber and family Zingiberaceae.
The phase change of sodium sulfate significantly affects the salt weathering of loess slopes in seasonal frozen regions, which should be involved in the modeling of heat, water and solute transfer. ...The governing equation for heat transfer was established based on the Harlan model by incorporating ice-water phase change and crystallization of sodium sulfate and an empirical relationship for thermal conductivity of saline loess. Regarding the moisture field, a modified factor that characterizes the impedance of salt crystals and ice on water migration in frozen area was introduced into the Gardner model. The total suction as a function of water and salt contents was included in the unfrozen water migration equation. Considering the convection, diffusion and phase change of solutes, the equation for salinity field was established by Darcy's and Fick's laws, with a solubility function based on the solubility curve of sodium sulfate. The above models were numerically implemented on COMSOL Multiphysics through the user-defined partial differential equation module. In order to verify the rationality of the method, the profiles of temperature, water and salt contents of saline loess columns obtained by uniaxial freezing tests in closed system were compared with the numerical results. Comparisons show that the simulated profiles of temperature, water and salt contents at three cold-end temperatures (−5, −10 and − 20 °C) agree well with the measured data. According to the profile of the amount of crystalline salt, the concept of uncrystallized zone was proposed, which is found to be positively related to the cold-end temperature.
•Crystallization of sodium sulfate was included in heat and water transfer equation.•Impedance of salt crystals on water migration was introduced to Gardner model.•The length of uncrystallized zone is positively related to cold-end temperature.
Glioblastoma (GBM) is the deadliest and most common type of primary brain tumor in adults with a grim prognosis despite multimodal treatments. Dendritic cell (DC)-based immunotherapy has emerged as a ...promising therapeutic modality for GBM, whose efficacy is nonetheless fundamentally undermined by GBM-induced immunosuppression. Inducing emission of damage associated molecular patterns (DAMPs) is a highly effective strategy to subvert tumor-associated immunosuppression. The present work was carried out to explore the idea of subverting the GBM immunosuppressive microenvironment through DC-mediated delivery of doxorubicin-polyglycerol-nanodiamond composites (Nano-DOX), a potent DAMPs inducer demonstrated by our previous study, and thereby eliciting enhanced DC-driven anti-GBM immune response. In the in-vitro work on human cell models, Nano-DOX-loaded DC were shown to be functionally viable and release cargo drug to co-cultured GBM cells (GC). Nano-DOX-treated GC displayed not only profuse DAMPs emission but also antigen release. Enhanced activation and acquisition and presentation of GC-derived antigen were then demonstrated in DC in co-culture with GC and Nano-DOX. Consistently, co-culture with GC and Nano-DOX also activated mouse bone marrow-derived DC (mDC) which in turn stimulated mouse spleen-derived lymphocytes which ultimately suppressed co-cultured GC. Next, athymic mice bearing orthotopic human GBM xenografts were intravenously injected with Nano-DOX-loaded mDC and, 48 h later, spleen-derived lymphocytes. The presence of Nano-DOX, DAMPs emission and enhanced infiltration and activation of mDC and lymphocytes were detected in the GBM xenografts. Taken together, our results demonstrate the efficacy of DC-mediated delivery of Nano-DOX to stimulate GC immunogenicity and elicit anti-cancer immune response in the GBM. By this work, we present a novel approach with great application potential to subverting the GBM immunosuppressive microenvironment and to anti-GBM immunotherapy. Investigation has also been conducted probing the mechanisms by which Nano-DOX stimulates GC immunogenicity, which is described in a follow-up paper.
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