Continuously emerging highly pathogenic coronaviruses remain a major threat to human and animal health. Porcine deltacoronavirus (PDCoV) is a newly emerging enterotropic swine coronavirus that causes ...large-scale outbreaks of severe diarrhea disease in piglets. Unlike other porcine coronaviruses, PDCoV has a wide range of species tissue tropism, including primary human cells, which poses a significant risk of cross-species transmission. Nucleotide-binding oligomerization domain-like receptor (NLR) family pyrin domain-containing 1 (NLRP1) has a key role in linking host innate immunity to microbes and the regulation of inflammatory pathways. We now report a role for NLRP1 in the control of PDCoV infection. Overexpression of NLRP1 remarkably suppressed PDCoV infection, whereas knockout of NLRP1 led to a significant increase in PDCoV replication. A mechanistic study revealed that NLRP1 suppressed PDCoV replication in cells by upregulating IL-11 expression, which in turn inhibited the phosphorylation of the ERK signaling pathway. Furthermore, the ERK phosphorylation inhibitor U0126 effectively hindered PDCoV replication in pigs. Together, our results demonstrated that NLRP1 exerted an anti-PDCoV effect by IL-11-mediated inhibition of the phosphorylation of the ERK signaling pathway, providing a novel antiviral signal axis of NLRP1-IL-11-ERK. This study expands our understanding of the regulatory network of NLRP1 in the host defense against virus infection and provides a new insight into the treatment of coronaviruses and the development of corresponding drugs.IMPORTANCECoronavirus, which mainly infects gastrointestinal and respiratory epithelial cells
, poses a huge threat to both humans and animals. Although porcine deltacoronavirus (PDCoV) is known to primarily cause fatal diarrhea in piglets, reports detected in plasma samples from Haitian children emphasize the potential risk of animal-to-human spillover. Finding effective therapeutics against coronaviruses is crucial for controlling viral infection. Nucleotide-binding oligomerization-like receptor (NLR) family pyrin domain-containing 1 (NLRP1), a key regulatory factor in the innate immune system, is highly expressed in epithelial cells and associated with the pathogenesis of viruses. We demonstrate here that NLRP1 inhibits the infection of the intestinal coronavirus PDCoV through IL-11-mediated phosphorylation inhibition of the ERK signaling pathway. Furthermore, the ERK phosphorylation inhibitor can control the infection of PDCoV in pigs. Our study emphasizes the importance of NLRP1 as an immune regulatory factor and may open up new avenues for the treatment of coronavirus infection.
Nucleotide-binding oligomerization domain 1 (NOD1) is an intracellular innate immune sensor for small molecules derived from bacterial cell components. NOD1 activation by its ligands leads to robust ...production of pro-inflammatory cytokines and chemokines by innate immune cells, thereby mediating mucosal host defense systems against microbes. Chronic gastric infection due to
(
) causes various upper gastrointestinal diseases, including atrophic gastritis, peptic ulcers, and gastric cancer. It is now generally accepted that detection of
by NOD1 expressed in gastric epithelial cells plays an indispensable role in mucosal host defense systems against this organism. Recent studies have revealed the molecular mechanism by which NOD1 activation caused by
infection is involved in the development of chronic gastritis and gastric cancer. In this review, we have discussed and summarized how sensing of
by NOD1 mediates the prevention of chronic gastritis and gastric cancer.
Atherosclerosis remains to be one of the most common vascular disorders resulting in morbidity and mortality in the world. Recent studies suggested that endothelial cells (ECs) injury caused by ...oxidative low-density lipoprotein (ox-LDL) is an early marker for atherosclerosis. Nevertheless, the mechanisms of ox-LDL-induced ECs injury are complicated and largely unknown. Here, we found lncRNA XIST (X-inactive specific transcript) was upregulated in human umbilical vein endothelial cells (HUVECs) stimulated by ox-LDL. Knockdown of XIST boosted the cell viability and suppressed cell apoptosis under ox-LDL stimuli. Further experiments identified XIST regulated the expression of Nucleotide-Binding Oligomerization Domain 2 (NOD2) by sponging miR-320. XIST silencing exerted a protective effect on ox-LDL-induced HUVECs injury via miR-320/NOD2 regulatory network. Our data provide insight into the role of the lncRNA XIST in ox-LDL mediated ECs injury, which can aid in developing new therapeutic strategies for the treatment of atherosclerosis.
•lncRNA XIST was upregulated in HUVECs stimulated by ox-LDL.•Knockdown of XIST boosted cell viability and suppressed cell apoptosis.•XIST regulated the expression of NOD2 by sponging miR-320.•XIST exerts its role via modulation of miR-320/NOD2 axis in ox-LDL-treated HUVECs.
The innate immune system is the first line of host defense, and it is capable of resisting both exogenous pathogenic challenges and endogenous danger signals via different pattern recognition ...receptors (PRRs), including Toll-like receptors, retinoic acid-inducible gene-1 (RIG-1)-like receptors, cytosolic DNA sensors, as well as nucleotide-binding oligomerization domain (NOD)-like receptors. After recognizing the pathogen-associated molecular patterns from exogenous microbes or the damage-associated molecular patterns from endogenous immune-stimulatory signals, these PRRs signaling pathways can induce the expression of interferons and inflammatory factors against microbial pathogen invasion and endogenous stresses. Calcium (Ca2+) is a second messenger that participates in the modulation of various biological processes, including survival, proliferation, apoptosis, and immune response, and is involved in diverse diseases, such as autoimmune diseases and virus infection. To date, accumulating evidence elucidated that the PRR signaling exhibited a regulatory effect on Ca2+ signaling. Meanwhile, Ca2+ signaling also played a critical role in controlling biological processes mediated by the PRR adaptors. Since the importance of these two signalings, it would be interesting to clarify the deeper biological implications of their interplays. This review focuses on the crosstalk between Ca2+ signaling and PRR signaling to regulate innate immune responses.
Gouty arthritis serves as an acute reaction initiated by the deposition of monosodium urate (MSU) crystals around the joints. In this study, the anti-inflammatory effects of phytochemical ...β-caryophyllene on MSU crystal-induced acute gouty arthritis
and in silico were explored. Through bioinformatics methods and molecular docking, it screened the specific influence pathway of β-caryophyllene on gout. Certain methods including enzyme-linked immunosorbent assay, western blotting, and immunohistochemical staining were adopted to quantify. β-caryophyllene significantly reduced inflammation and function of ankle joints in MSU Crystals-induced gouty arthritis rats, while decreasing serum cytokine levels. Furthermore, it inhibited the expressions of NLRP3, Caspase-1, ASC, TLR4, MyD88, p65, and IL-1β in the synovial tissue so as to reduce inflammation and protect ankle joints' function. A new research approach in which β-caryophyllene treatment to acute attacks of gout is provided through the research results.
Summary
Formation of supramolecular assemblies appears to be a general mechanism in immune signalling pathways. These supramolecular assemblies appear to form through a nucleated polymerization ...mechanism. This review examines selected immune signalling pathways that involve supramolecular assemblies, describes the concepts of protein polymerization, and discusses how those concepts of protein polymerization implicate new elegant ways for signal amplification, setting threshold and noise reduction in these pathways.
Formation of supramolecular assemblies appears to be a general mechanism in immune signalling pathways. This review examines selected immune signalling pathways that involve supramolecular assemblies, describes the concepts of protein polymerization, and discusses how those concepts may implicate new molecular mechanisms in signal transduction.
Decidual stromal cells (DSCs) are known to regulate trophoblast invasion via unveiled mechanism yet. And nucleotide‐binding oligomerization domain‐containing protein 1 (NOD1) may influence on this ...DSC‐trophoblast interaction. We investigated the mechanism underlying the DSC‐mediated regulation of trophoblast invasion and the effect of NOD1 on their cross talk. Using human primary DSCs, BeWo cell invasion was measured. Cytokine secretion and MAP kinase signaling were examined in DSCs following treatment with NOD1 agonist, Tri‐DAP. DSCs secreted IL‐8 and increased trophoblast invasion. Tri‐DAP further increased IL‐8 secretion from DSCs via JNK pathway and facilitated both MMP‐2 production and trophoblast invasion compared with control. Upon cotreatment of IL‐8 and anti‐IL‐8 antibody to BeWo cells, the number of invading trophoblasts and MMP‐2 production decreased significantly. These results suggest that IL‐8 from DSCs may play a role to increase the invasiveness of trophoblast cells into the decidua via NOD1/JNK pathway.
Diabetic retinopathy(DR)is a neurovascular disease caused by the neurovascular unit(NVU)impairment. Immune imbalance and inflammation are key factors that affect the normal function of NVU and lead ...to the progression of DR. Nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3)inflammasome is indicated as an important component of the inflammatory response, and it can identify endogenous danger signals, leading to the activation of caspase-1 and then activating a series of inflammatory cytokines and pyroptosis. Early activation of inflammasome maintains and promotes innate immunity against bacterial and viral infections, while excessive inflammasome activation results in excessive expression and ongoing action of inflammatory proteins, which in turn triggers off immune disorders and an inflammatory cascade that seriously harms the body. This review summarizes the recent research progress on the mechanism of NLRP3 inflammasome in NVU impairment of DR, including the related drugs targeting NLRP3 pathways.
Blau syndrome (BS) is a rare dominantly inherited autoinflammatory disorder associated with mutations in the nucleotide-binding oligomerization domain containing 2 (NOD2) gene. Biologic therapy of BS ...yielded diverse results. We aimed to evaluate clinical features and outcomes of Chinese patients with BS who were treated with tumor necrosis factor (TNF)α inhibitors.
A total of four patients with BS were diagnosed and treated with infliximab (IFX) at the Peking Union Medical College Hospital during 2015 to 2018 and were followed up for 18 months. All patients were systematically studied for treatment outcomes including the clinical manifestations and inflammatory markers. We also conducted a comprehensive literature review about TNFα inhibitor therapy in BS.
Four BS patients were all Chinese Han, and three were women. The mean age of disease onset was 4 ± 3.5 years, and the mean time of diagnosis delay was 19 ± 11 years. All patients received IFX plus methotrexate, and all achieved clinical remission of skin lesions and polyarthritis rapidly, as well as normalization of erythrocyte sedimentation rate and C-reactive protein and improvements in inflammatory cytokines, patient visual analogue scale, physician global assessment, and Short Form (SF)-36, at the first follow-up of 6 months. The disease relapsed in two patients after they lengthened the interval of IFX and discontinued methotrexate. According to the 38 English-language publications, 62 patients with BS were reported who underwent TNFα inhibitor therapy, including IFX used in 31, adalimumab in 24, and etanercept in 7. IFX was well tolerated in 27 patients, while 2 still had uveitis, and the other 2 experienced an adverse drug reaction.
Early recognition and effective treatment of BS are very important to avoid irreversible organ damage. TNFα inhibitors such as IFX may be a promising approach for BS patients who have unsatisfactory response to corticosteroids and traditional disease-modifying antirheumatic drugs.
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