Adaptor protein HIP-55 promotes macrophage M1 polarization through promoting AP-1 complex activation

Overwhelming macrophage M1 polarization induced by malfunction of the renin-angiotensin-aldosterone system (RAAS) initiates inflammatory responses, which play a crucial role in various cardiovascular diseases. However, the underlying regulatory mechanism remains elusive. Here, we identified adaptor protein HIP-55 as a critical regulator of macrophage M1 polarization. The expression of HIP-55 was upregulated in M1 macrophage induced by Ang II. Overexpression of HIP-55 significantly promoted Ang II-induced macrophage M1 polarization, whereas genetic deletion of HIP-55 inhibited the Ang II-induced macrophage M1 polarization. Mechanistically, HIP-55 facilitated activator protein-1 (AP-1) complex activation induced by Ang II via promoting ERK1/2 and JNK phosphorylation. Moreover, blocking AP-1 complex activation can attenuate the function of HIP-55 in macrophage polarization. Collectively, our results reveal the role of HIP-55 in macrophage polarization and provide potential therapeutic insights for cardiovascular diseases associated with RAAS dysfunction.

Effects of almond (Armeniaca Sibirica L. Lam) polysaccharides on gut microbiota and anti-inflammatory effects on LPS-induced RAW264.7 cells

The aim of this study was to investigate the prebiotic properties of the almond polysaccharide AP-1 on intestinal microorganisms by using an in vitro fecal fermentation method and its anti-inflammatory effect on lipopolysaccharide (LPS)-induced RAW264.7 cells. The results showed that during the in vitro fermentation of AP-1, the pH value of the fermentation broth decreased obviously, while the concentration of short-chain fatty acids (SCFAs) increased significantly, especially acetic acid and butyric acid. In genus level, the number of Clostridium and Megamonas increased markedly in the AP-1 group after 24 h of fermentation. After 48 h of fermentation, there was a noticeable increase in the number of beneficial genera Lactobacillaceae and Bifidobacteriaceae, and a considerable decrease in the number of pro-inflammatory genera. In addition, we found that AP-1 had no toxic effect on RAW264.7 cells. In the LPS-induced inflammation model of RAW264.7 cells, AP-1 could effectively inhibit the release of NO, regulate the level of reactive oxides (ROS), and effectively down-regulate the mRNA expression of TNF-α, IL-1β, IL-6 and iNOS. In conclusion, the almond polysaccharide AP-1 may be a functional active substance aimed at promoting intestinal health and exerting anti-inflammatory effects.

Molecular mechanism of Jianpiyifei II granules in the treatment of chronic obstructive pulmonary disease: Network pharmacology analysis, molecular docking, and experimental assessment

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is defined by persistent airway and lung inflammation, excessive mucus production, remodeling of the airways, and damage to the alveolar tissue. Based on clinical experience, it has been observed that Jianpiyifei II (JPYF II) granules exhibit a significant therapeutic impact on individuals suffering from stable COPD. Nevertheless, the complete understanding of JPYF II's potential mode of action against COPD remains to be further clarified.

PURPOSE

To further investigate the underlying mechanism of JPYF II for treating COPD and clarify the role of the IL-17 pathway in the treatment.

METHODS

A variety of databases were utilized to acquire JPYF II's bioactive components, as well as related targets of JPYF II and COPD. Cytoscape was utilized to establish multiple interaction networks for the purpose of topological analyses and core-target screening. The Metascape was utilized to identify the function of target genes and crucial signaling pathways. To evaluate the interactions between bioactive ingredients and central target proteins, molecular docking simulations were conducted. Following that, a sequence of experiments was conducted both in the laboratory and in living organisms, which included analyzing the cell counts in bronchoalveolar lavage fluid (BALF), examining lung tissue for histopathological changes, conducting immunohistochemistry, RT‒qPCR, ELISA, and Western blotting.

RESULTS

In JPYF II, 88 bioactive ingredients were predicted to have a total of 342 targets. After conducting Venn analysis, it was discovered that 284 potential targets of JPYF II were linked to the provision of defensive benefits against COPD. The PPI network yielded a total of twenty-four core targets. The findings from the analysis of enrichment and gene‒pathway network suggested that JPYF II targeted Hsp90, MAPKs, ERK, AP-1, TNF-α, IL-6, COX-2, CXCL8, and MMP-9 as crucial elements for COPD treatment through the IL-17 pathway. Additionally, JPYF II might modulate MAPK signaling pathways and the downstream transcription factor AP-1 via IL-17 regulation. According to the findings from molecular docking, it was observed that the 24 core target proteins exhibited robust binding affinities towards the top 10 bioactive compounds. Furthermore, the treatment of COPD through the regulation of MAPKs in the IL-17 pathway was significantly influenced by flavonoids and sterols found in JPYF II. In vitro, these observations were further confirmed. In vivo results demonstrated that JPYF II reduced inflammatory cell infiltration in pulmonary tissues and the quantity of inflammatory cells in BALF obtained from LPS- and CS-stimulated mice. Moreover, the administration of JPYF II resulted in the inhibition of IL-17 mRNA and protein levels, phosphorylation levels of MAPK proteins, and expression of phosphorylated AP-1 proteins. It also suppressed the expression of downstream effector genes and proteins associated with the IL-17/MAPK/AP-1 signaling axis in lung tissues and BALF.

CONCLUSION

This research reveals that JPYF II improves COPD by controlling the IL-17/MAPK/AP-1 signaling axis within the IL-17 pathway for the first time. These findings offer potential approaches for the creation of novel medications that specifically target IL-17 and proteins involved in the IL-17 pathway to address COPD.

Infant Whole-Cell Versus Acellular Pertussis Vaccination in 1997 to 1999 and Risk of Childhood Hospitalization for Food-Induced Anaphylaxis: Linked Administrative Databases Cohort Study

BACKGROUND

Evidence suggests that children who had received an initial priming dose of whole-cell pertussis (wP) vaccine, rather than acellular pertussis (aP) vaccine, had a lower risk of developing IgE-mediated food allergy, the most common cause of anaphylaxis-related hospital presentations of childhood.

OBJECTIVE

To assess the association between wP versus aP vaccination in infancy and subsequent hospital presentations for anaphylaxis.

METHODS

This study was preregistered under PMID 34874968. Perinatal records for a cohort of New South Wales-born children (1997-1999) receiving their first dose of pertussis-containing vaccine before age 4 months were probabilistically linked to hospital and immunization records. We used adjusted Cox models to estimate hazard ratios (aHRs) and 95% CIs for anaphylaxis-coded hospitalizations.

RESULTS

There were 218,093 New South Wales-born children who received a first dose of wP or aP before age 4 months. Among these children, 86 experienced at least one hospitalization for food-induced anaphylaxis at age 5-15 years (range of events per patient, one to three). The person-time of follow-up was 1,476,969 years, and 665,519 years for children vaccinated with wP as a first dose (wP-1 children) and aP as a first dose (aP-1 children), respectively. The incidence rates for first hospitalization for food anaphylaxis were 3.5 (95% CI, 2.6-4.6) and 5.1 (95% CI, 3.5-7.1) per 100,000 child-years among wP-1 children and aP-1 children, respectively (aHR for wP vs aP = 0.47; 95% CI, 0.26-0.83). For first admission for venom anaphylaxis, the incidence rate was 4.9 (95% CI, 3.9-6.2) per 100,000 child-years among wP-1 children and 5.1 (95% CI, 3.5-7.1) per 100,000 child-years among aP-1 children (aHR for wP vs aP = 0.92; 95% CI, 0.53-1.60), and for all-cause anaphylaxis, the incidence rate was 10.6 (95% CI, 9.0-12.4) per 100,000 child-years among wP-1 children and 12.8 (95% CI, 10.2-15.8) per 100,000 child-years among aP-1 children (aHR for wP vs aP = 0.92; 95% CI, 0.53-1.60).

CONCLUSION

Vaccination with wP in infancy was associated with a lower risk of hospitalizations for food-induced anaphylaxis (and therefore severe IgE-mediated food allergy) occurring in childhood.

Identification of central regulators related to abdominal fat deposition in chickens based on weighted gene co-expression network analysis

Abdominal fat (AF) is one of the most important economic traits in chickens. Excessive AF in chickens will reduce feed utilization efficiency and negatively affect reproductive performance and disease resistance. However, the regulatory network of AF deposition needs to be further elucidated. In the present study, 300 one-day-old female Wannan chickens were reared to 17 wk of age, and 200 Wannan hens were selected to determine the abdominal fat percentage (AFP). Twenty AF tissue samples with the lowest AFP were selected as the low abdominal fat group (L-AFG), and 20 AF tissue samples with the highest AFP were selected as the high abdominal fat group (H-AFG). Eleven samples from L-AFG and 14 samples from H-AFG were selected for RNA-seq and used for weighted gene co-expression network analysis (WGCNA). Among the 25 RNA-seq samples, 5 samples with the lowest and highest AFP values were selected for differential expression gene analysis. Compared with the L-AFG, 225 and 101 genes were upregulated and downregulated in the H-AFG, respectively. A total of 20,503 genes were used to construct the WGCNA, and 44 co-expression gene modules were identified. Among these modules, 3 modules including turquoise, darkorange2, and floralwhite were identified as significantly associated with AFP traits. Furthermore, several genes including acyl-CoA oxidase 1 (ACOX1), stearoyl-CoA desaturase (SCD), aldehyde dehydrogenase 6 family member A1 (ALDH6A1), jun proto-oncogene, AP-1 transcription factor subunit (JUN), and fos proto-oncogene, AP-1 transcription factor subunit (FOS) involved in the "PPAR signaling pathway," "fatty acid metabolism," and "MAPK signaling pathway" were identified as central regulators that contribute to AF deposition. These results provide valuable information for further understanding of the gene expression and regulation of AF traits and contribute to future molecular breeding for AF in chickens.

Effect of Echinacea purpurea (L.) Moench and its extracts on the immunization outcome of avian influenza vaccine in broilers

ETHNOPHARMACOLOGICAL RELEVANCE

Echinacea purpurea (L.) Moench (EP) is a perennial herbaceous flowering plant with immunomodulatory effects. However, the immunomodulatory effects of EP on broilers after vaccination are still unclear.

AIM OF THE STUDY

The aim is to study the effect of EP and Echinacea purpurea (L.) Moench extracts(EE) on avian influenza virus (AIV) immunity, and further explore the potential mechanism of immune regulation.

MATERIALS AND METHODS

Broilers were fed with feed additives containing 2% EP or 0.5% EE, and vaccinated against avian influenza. The samples were collected on the 7th, 21st, and 35th day after vaccination, and the feed conversion ratio (FCR) was calculated. Blood antibody titer, jejunal sIgA content, tight junction protein, gene and protein expression of TLR4-MAPK signaling pathway were also detected.

RESULTS

The results showed that vaccination could cause immune stress, weight loss, increase sIgA content, and up-regulate the expression of tight junction proteins, including zonula occludens-1 (ZO-1), Occludin, and Claudin-1, as well as the genes of Toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), receptor-associated factor 6 (TRAF6), activator protein 1 (AP-1) protein gene expression on TLR4-mitogen-activated protein kinase (MAPK) signaling pathway, and the protein expression of MyD88, extracellular regulated protein kinases (ERK), and c-Jun N-terminal kinase (JNK). EP and EE could increase the body weight of broilers, further improve antibody titers, decrease FCR, increase sIgA levels, up-regulate the expression of tight junction proteins, including ZO-1, Occludin, and Claudin-1, as well as the genes of TLR4, MyD88, TRAF6, and AP-1 and the protein expression of MyD88, ERK, and JNK in the TLR4-MAPK signaling pathway.

CONCLUSION

In conclusion, EP and EE can increase the broiler's production performance and improve vaccine immune effect through the TLR4-MAPK signaling pathway.

The activator protein-1 complex governs a vascular degenerative transcriptional programme in smooth muscle cells to trigger aortic dissection and rupture

BACKGROUND AND AIMS

Stanford type A aortic dissection (AD) is a degenerative aortic remodelling disease marked by an exceedingly high mortality without effective pharmacologic therapies. Smooth muscle cells (SMCs) lining tunica media adopt a range of states, and their transformation from contractile to synthetic phenotypes fundamentally triggers AD. However, the underlying pathomechanisms governing this population shift and subsequent AD, particularly at distinct disease temporal stages, remain elusive.

METHODS

Ascending aortas from nine patients undergoing ascending aorta replacement and five individuals undergoing heart transplantation were subjected to single-cell RNA sequencing. The pathogenic targets governing the phenotypic switch of SMCs were identified by trajectory inference, functional scoring, single-cell regulatory network inference and clustering, regulon, and interactome analyses and confirmed using human ascending aortas, primary SMCs, and a β-aminopropionitrile monofumarate-induced AD model.

RESULTS

The transcriptional profiles of 93 397 cells revealed a dynamic temporal-specific phenotypic transition and marked elevation of the activator protein-1 (AP-1) complex, actively enabling synthetic SMC expansion. Mechanistically, tumour necrosis factor signalling enhanced AP-1 transcriptional activity by dampening mitochondrial oxidative phosphorylation (OXPHOS). Targeting this axis with the OXPHOS enhancer coenzyme Q10 or AP-1-specific inhibitor T-5224 impedes phenotypic transition and aortic degeneration while improving survival by 42.88% (58.3%-83.3% for coenzyme Q10 treatment), 150.15% (33.3%-83.3% for 2-week T-5224), and 175.38% (33.3%-91.7% for 3-week T-5224) in the β-aminopropionitrile monofumarate-induced AD model.

CONCLUSIONS

This cross-sectional compendium of cellular atlas of human ascending aortas during AD progression provides previously unappreciated insights into a transcriptional programme permitting aortic degeneration, highlighting a translational proof of concept for an anti-remodelling intervention as an attractive strategy to manage temporal-specific AD by modulating the tumour necrosis factor-OXPHOS-AP-1 axis.

Characteristics of the synovial microenvironment and synovial mesenchymal stem cells with hip osteoarthritis of different bone morphologies

BACKGROUND

Variations in bone morphology in patients with hip osteoarthritis (HOA) can be broadly categorized into three types: atrophic, normotrophic, and hypertrophic. Despite the investigations examining clinical elements, such as bone morphology, pain, and range of motion, our understanding of the pathogenesis of HOA remains limited. Previous studies have suggested that osteophytes typically originate at the interface of the joint cartilage, periosteum, and synovium, potentially implicating synovial mesenchymal stem cells (SMSCs) in the process. This study aimed to investigate the potential factors that drive the development of bone morphological features in HOA by investigating the characteristics of the synovium, differentiation potential of SMSCs, and composition of synovial fluid in different types of HOA.

METHODS

Synovial tissue and fluid were collected from 30 patients who underwent total hip arthroplasty (THA) with the variable bone morphology of HOA patients. RNA sequencing analysis and quantitative reverse transcription-polymerase chain reaction (RT-qPCR) were performed to analyse the genes in the normotrophic and hypertrophic synovial tissue. SMSCs were isolated and cultured from the normotrophic and hypertrophic synovial tissues of each hip joint in accordance with the variable bone morphology of HOA patients. Cell differentiation potential was compared using differentiation and colony-forming unit assays. Cytokine array was performed to analyse the protein expression in the synovial fluid.

RESULTS

In the RNA sequencing analysis, 103 differentially expressed genes (DEGs) were identified, predominantly related to the interleukin 17 (IL-17) signalling pathway. Using a protein-protein interaction (PPI) network, 20 hub genes were identified, including MYC, CXCL8, ATF3, NR4A1, ZC3H12A, NR4A2, FOSB, and FOSL1. Among these hub genes, four belonged to the AP-1 family. There were no significant differences in the tri-lineage differentiation potential and colony-forming capacity of SMSCs. However, RT-qPCR revealed elevated SOX9 expression levels in synovial tissues from the hypertrophic group. The cytokine array demonstrated significantly higher levels of CXCL8, MMP9, and VEGF in the synovial fluid of the hypertrophic group than in the normotrophic group, with CXCL8 and MMP9 being significantly expressed in the hypertrophic synovium.

CONCLUSION

Upregulation of AP-1 family genes in the synovium and increased concentrations of CXCL8, MMP9, and VEGF were detected in the synovial fluid of the hypertrophic group of HOA patients, potentially stimulating the differentiation of SMSCs towards the cartilage and thereby contributing to severe osteophyte formation.

SH3RF2 contributes to cisplatin resistance in ovarian cancer cells by promoting RBPMS degradation

Platinum-based chemotherapy remains one of the major choices for treatment of ovarian cancer (OC). However, primary or acquired drug resistance severely impairs their efficiency, thereby causing chemotherapy failure and poor prognosis. SH3 domain containing ring finger 2 (SH3RF2) has been linked to the development of cancer. Here we find higher levels of SH3RF2 in the tumor tissues from cisplatin-resistant OC patients when compared to those from cisplatin-sensitive patients. Similarly, cisplatin-resistant OC cells also express higher levels of SH3RF2 than normal OC cells. Through in vitro and in vivo loss-of-function experiments, SH3RF2 is identified as a driver of cisplatin resistance, as evidenced by increases in cisplatin-induced cell apoptosis and DNA damage and decreases in cell proliferation induced by SH3RF2 depletion. Mechanistically, SH3RF2 can directly bind to the RNA-binding protein mRNA processing factor (RBPMS). RBPMS has been reported as an inhibitor of cisplatin resistance in OC. As a E3 ligase, SH3RF2 promotes the K48-linked ubiquitination of RBPMS to increase its proteasomal degradation and activator protein 1 (AP-1) transactivation. Impairments in RBPMS function reverse the inhibitory effect of SH3RF2 depletion on cisplatin resistance. Collectively, the SH3RF2-RBPMS-AP-1 axis is an important regulator in cisplatin resistance and inhibition of SH3RF2 may be a potential target in preventing cisplatin resistance.

Impact of HPV strains on molecular mechanisms of cervix cancer

PURPOSE

Cervical cancer accounts for a high number of deaths worldwide. Risk factors are extensive for cervix cancer but Human papillomavirus (HPV) plays a prime role in its development. Different strains of HPV are prevalent globally, which show different grades of mortality and morbidity among women. This study is planned to evaluate the molecular mechanism of different strains of HPV infection and progression leading to cervix cancer.

METHODS

This review includes different research articles on cervix cancer progression reported from India and all over the world.

RESULTS

HPV 16 and 18 are prevalent strains using heparan sulfate-independent and dependent pathways for viral replication inside the cell. It also uses transcription mechanisms through NF-kappa B, FOXA-1, and AP-1 genes while strains like HPV-35, 45, and 52 are also predominant in India, which showed a very slow mechanism of progression due to which mortality rate is low after their infection with these strains.

CONCLUSION

HPV uses E6 and E7 proteins which activate NF-kappa B and AP-1 pathway which suppresses the tumor suppressor gene and activates cytokine production, causing inflammation and leading to a decrease in apoptosis due to Caspase-3 activation. In contrast, the E7 protein involves HOXA genes and decreases apoptotic factors due to which mortality and incidence rates are low in viruses that use E7 motifs. Some HPV strains employ the cap-dependent pathway, which is also associated with lower mortality and infection rates.

[Is it possible to detect surface antigen CD133 on patient-derived glioblastoma continuous cell cultures using fluorescent aptamers?]

Theranostics combines diagnostics and therapeutic exposure. Regarding glioblastomas, theranostics solves the problem of detecting and destroying tumor stem cells resistant to irradiation and chemotherapy and causing tumor recurrence. Transmembrane surface antigen CD133 is considered as a potential marker of tumor stem cells.

OBJECTIVE

To detect CD133 in patient-derived glioblastoma continuous cell cultures using fluorescence microscopy and modified aptamers (molecular recognition elements) anti-CD133.

MATERIAL AND METHODS

To detect CD133, we used mousey fluorescence monoclonal antibodies anti-CD133 MA1-219, FAM-modified DNA aptamers anti-CD133 AP-1-M and Cs5. Non-aptamer DNA oligonucleotide NADO was used as a negative control. Detection was performed for three samples of patient-derived glioblastoma continuous cell cultures coded as 1548, 1721 and 1793.

RESULTS

MA1-219 antibodies brightly stained cell culture 1548, to a lesser extent - 1721. There was diffuse staining of cell culture 1793. Cs5-FAM aptamer stained cells in a similar way, but much weaker. AP-1-M-FAM aptamer interacted with cells even weaker and diffusely stained only cell culture 1793. Non-aptamer NADO did not stain cell culture 1548 and very weakly diffusely stained cell culture 1793.

CONCLUSION

For both molecular recognition elements (MA1-219 antibody and Cs5 aptamer), 3 cell culture samples can be arranged in the following order possibly reflecting CD133 status decrease: strong signal for cell culture 1548, much weaker for 1721, even weaker for 1793. Only cell culture 1548 can be considered CD133 positive with combination of Cs5+ and NADO signals. Cell culture 1793 is CD133 false positive with combination of Cs5+ and NADO+ signals.

IFITM3-mediated activation of TRAF6/MAPK/AP-1 pathways induces acquired TKI resistance in clear cell renal cell carcinoma

PURPOSE

Vascular endothelial growth factor tyrosine kinase inhibitors (TKIs) have been the standard of care for advanced and metastatic clear cell renal cell carcinoma (ccRCC). However, the therapeutic effect of TKI monotherapy remains unsatisfactory given the high rates of acquired resistance to TKI therapy despite favorable initial tumor response.

MATERIALS AND METHODS

To define the TKI-resistance mechanism and identify new therapeutic target for TKI-resistant ccRCC, an integrative differential gene expression analysis was performed using acquired resistant cohort and a public dataset. Sunitinib-resistant RCC cell lines were established and used to test their malignant behaviors of TKI resistance through in vitro and in vivo studies. Immunohistochemistry was conducted to compare expression between the tumor and normal kidney and verify expression of pathway-related proteins.

RESULTS

Integrated differential gene expression analysis revealed increased interferon-induced transmembrane protein 3 (IFITM3) expression in post-TKI samples. IFITM3 expression was increased in ccRCC compared with the normal kidney. TKI-resistant RCC cells showed high expression of IFITM3 compared with TKI-sensitive cells and displayed aggressive biologic features such as higher proliferative ability, clonogenic survival, migration, and invasion while being treated with sunitinib. These aggressive features were suppressed by the inhibition of IFITM3 expression and promoted by IFITM3 overexpression, and these findings were confirmed in a xenograft model. IFITM3-mediated TKI resistance was associated with the activation of TRAF6 and MAPK/AP-1 pathways.

CONCLUSIONS

These results demonstrate IFITM3-mediated activation of the TRAF6/MAPK/AP-1 pathways as a mechanism of acquired TKI resistance, and suggest IFITM3 as a new target for TKI-resistant ccRCC.

BATF represses BIM to sustain tolerant T cells in the periphery

T cells that encounter self-antigens after exiting the thymus avert autoimmunity through peripheral tolerance. Pathways for this include an unresponsive state known as anergy, clonal deletion, and T regulatory (Treg) cell induction. The transcription factor cues and kinetics that guide distinct peripheral tolerance outcomes remain unclear. Here, we found that anergic T cells are epigenetically primed for regulation by the non-classical AP-1 family member BATF. Tolerized BATF-deficient CD4+ T cells were resistant to anergy induction and instead underwent clonal deletion due to proapoptotic BIM (Bcl2l11) upregulation. During prolonged antigen exposure, BIM derepression resulted in fewer PD-1+ conventional T cells as well as loss of peripherally induced FOXP3+ Treg cells. Simultaneous Batf and Bcl2l11 knockdown meanwhile restored anergic T cell survival and Treg cell maintenance. The data identify the AP-1 nuclear factor BATF as a dominant driver of sustained T cell anergy and illustrate a mechanism for divergent peripheral tolerance fates.

Angiotensin-(1-7) attenuates SARS-CoV2 spike protein-induced interleukin-6 and interleukin-8 production in alveolar epithelial cells through activation of Mas receptor

BACKGROUND

SARS-CoV-2 spike proteins (SP) can bind to the human angiotensin-converting enzyme 2 (ACE2) in human pulmonary alveolar epithelial cells (HPAEpiC) and trigger an inflammatory process. Angiotensin-(1-7) may have an anti-inflammatory effect through activation of Mas receptor. This study aims to investigate whether SARS-CoV-2 SP can induce inflammation through ACE2 in the alveolar epithelial cells which can be modulated through angiotensin-(1-7)/Mas receptor axis.

METHODS

HPAEpiC were treated with SARS-CoV-2 SP in the presence or absence of ACE2 antagonist-dalbavancin and Mas receptor agonist-angiotensin-(1-7). Proinflammatory cytokine production (IL-6 and IL-8) were measured at mRNA and protein levels. MAP kinase phosphorylation and transcription factor activation was determined by Western Blot. Mas receptor was blocked by either antagonist (A779) or knockdown (specific SiRNA). Experiments were replicated using A549 cells.

FINDINGS

SARS-CoV-2 SP (5 μg/mL) significantly induced MAP kinase (ERK1/2) phosphorylation, downstream transcription factor (activator protein-1, AP-1) activation and cytokine production (IL-6 and IL-8) at both mRNA and protein levels. Pretreatment with dalbavancin (10 μg/mL), or angiotensin-(1-7) (10 μM) significantly reduced ERK1/2 phosphorylation, AP-1 activation, and cytokine production. However, these angiotensin-(1-7)-related protective effects were significantly abolished by blocking Mas receptor with either antagonist (A799,10 μM) or SiRNA knockdown.

INTERPRETATION

SARS-CoV-2 SP can induce proinflammatory cytokine production, which can be inhibited by either ACE2 antagonist or Mas receptor agonist-angiotensin-(1-7). Angiotensin-(1-7)-related protective effect on cytokine reduction can be abolished by blocking Mas receptor. Our findings suggest that ACE2/angiotensin-(1-7)/Mas axis may serve as a therapeutic target to control inflammatory response triggered by SARS-CoV-2 SP.

PI(3,4,5)P3 allosteric regulation of repressor activator protein 1 controls antigenic variation in trypanosomes

African trypanosomes evade host immune clearance by antigenic variation, causing persistent infections in humans and animals. These parasites express a homogeneous surface coat of variant surface glycoproteins (VSGs). They transcribe one out of hundreds of VSG genes at a time from telomeric expression sites (ESs) and periodically change the VSG expressed by transcriptional switching or recombination. The mechanisms underlying the control of VSG switching and its developmental silencing remain elusive. We report that telomeric ES activation and silencing entail an on/off genetic switch controlled by a nuclear phosphoinositide signaling system. This system includes a nuclear phosphatidylinositol 5-phosphatase (PIP5Pase), its substrate PI(3,4,5)P3, and the repressor-activator protein 1 (RAP1). RAP1 binds to ES sequences flanking VSG genes via its DNA binding domains and represses VSG transcription. In contrast, PI(3,4,5)P3 binds to the N-terminus of RAP1 and controls its DNA binding activity. Transient inactivation of PIP5Pase results in the accumulation of nuclear PI(3,4,5)P3, which binds RAP1 and displaces it from ESs, activating transcription of silent ESs and VSG switching. The system is also required for the developmental silencing of VSG genes. The data provides a mechanism controlling reversible telomere silencing essential for the periodic switching in VSG expression and its developmental regulation.

Single-cell epigenetic, transcriptional, and protein profiling of latent and active HIV-1 reservoir revealed that IKZF3 promotes HIV-1 persistence

Understanding how HIV-1-infected cells proliferate and persist is key to HIV-1 eradication, but the heterogeneity and rarity of HIV-1-infected cells hamper mechanistic interrogations. Here, we used single-cell DOGMA-seq to simultaneously capture transcription factor accessibility, transcriptome, surface proteins, HIV-1 DNA, and HIV-1 RNA in memory CD4+ T cells from six people living with HIV-1 during viremia and after suppressive antiretroviral therapy. We identified increased transcription factor accessibility in latent HIV-1-infected cells (RORC) and transcriptionally active HIV-1-infected cells (interferon regulatory transcription factor [IRF] and activator protein 1 [AP-1]). A proliferation program (IKZF3, IL21, BIRC5, and MKI67 co-expression) promoted the survival of transcriptionally active HIV-1-infected cells. Both latent and transcriptionally active HIV-1-infected cells had increased IKZF3 (Aiolos) expression. Distinct epigenetic programs drove the heterogeneous cellular states of HIV-1-infected cells: IRF:activation, Eomes:cytotoxic effector differentiation, AP-1:migration, and cell death. Our study revealed the single-cell epigenetic, transcriptional, and protein states of latent and transcriptionally active HIV-1-infected cells and cellular programs promoting HIV-1 persistence.

Autoantibodies from patients with kidney allograft vasculopathy stimulate a proinflammatory switch in endothelial cells and monocytes mediated via GPCR-directed PAR1-TNF-α signaling

Non-HLA-directed regulatory autoantibodies (RABs) are known to target G-protein coupled receptors (GPCRs) and thereby contribute to kidney transplant vasculopathy and failure. However, the detailed underlying signaling mechanisms in human microvascular endothelial cells (HMECs) and immune cells need to be clarified in more detail. In this study, we compared the immune stimulatory effects and concomitant intracellular and extracellular signaling mechanisms of immunoglobulin G (IgG)-fractions from kidney transplant patients with allograft vasculopathy (KTx-IgG), to that from patients without vasculopathy, or matched healthy controls (Con-IgG). We found that KTx-IgG from patients with vasculopathy, but not KTx-IgG from patients without vasculopathy or Con-IgG, elicits HMEC activation and subsequent upregulation and secretion of tumor necrosis factor alpha (TNF-α) from HMECs, which was amplified in the presence of the protease-activated thrombin receptor 1 (PAR1) activator thrombin, but could be omitted by selectively blocking the PAR1 receptor. The amount and activity of the TNF-α secreted by HMECs stimulated with KTx-IgG from patients with vasculopathy was sufficient to induce subsequent THP-1 monocytic cell activation. Furthermore, AP-1/c-FOS, was identified as crucial transcription factor complex controlling the KTx-IgG-induced endothelial TNF-α synthesis, and mircoRNA-let-7f-5p as a regulatory element in modulating the underlying signaling cascade. In conclusion, exposure of HMECs to KTx-IgG from patients with allograft vasculopathy, but not KTx-IgG from patients without vasculopathy or healthy Con-IgG, triggers signaling through the PAR1-AP-1/c-FOS-miRNA-let7-axis, to control TNF-α gene transcription and TNF-α-induced monocyte activation. These observations offer a greater mechanistic understanding of endothelial cells and subsequent immune cell activation in the clinical setting of transplant vasculopathy that can eventually lead to transplant failure, irrespective of alloantigen-directed responses.

Ultrasound-assisted extraction and characterization of Penthorum chinense polysaccharide with anti-inflammatory effects

Penthorum chinense has been used in both food and medication for many years, and polysaccharide of which was considered as one of the bioactive compounds. However, the extraction process of polysaccharide from P. chinense (PCP) was not well optimized. Ultrasound-assisted extractionhas been widely employed in the extraction of natural products for its compliance with the concept of green and economic chemistry. To better investigate the structure and biology activity of PCP, response surface methodology was employed to optimize the ultrasound-assisted extraction conditions of PCP. The optimum extraction for the ultrasound-assisted extraction of PCP were obtained as ratio of solvent to material 40 mL/g, ultrasonic power 380 W, and extraction time of 50 min. The yield of PCP reached 8.71% under these optimized conditions. PCP was further purified by using anion exchange chromatography and gel filtration, an acidic fraction PCP-AP-1 was hereby obtained. The results of structural elucidation indicated that PCP-AP-1 was a typical pectic polysaccharide with a molecular weight of 66360 Da, mainly composed of galacturonic acid (68.5 mol%), followed by arabinose (9.8 mol%), rhamnose (9.4 mol%), glucose (7.7 mol%), with homogalacturonan region and rhamnogalacturonan I regions. In vitro study showed that PCP-AP-1 could improve the inflammation induced by lipopolysaccharide in intestinal epithelial cells, which was probably performed through the inhibition of multiple signaling pathways including the inhibition of TLR4, NOD1/2 and NF-κB pathway, as well as the reduction of NLRP3 inflammasome. This study defined the type of polysaccharide present in P. chinense and revealed a potential of application this plant in the prevention of intestinal inflammatory diseases.

A Rab6 to Rab11 transition is required for dense-core granule and exosome biogenesis in Drosophila secondary cells

Secretory cells in glands and the nervous system frequently package and store proteins destined for regulated secretion in dense-core granules (DCGs), which disperse when released from the cell surface. Despite the relevance of this dynamic process to diseases such as diabetes and human neurodegenerative disorders, our mechanistic understanding is relatively limited, because of the lack of good cell models to follow the nanoscale events involved. Here, we employ the prostate-like secondary cells (SCs) of the Drosophila male accessory gland to dissect the cell biology and genetics of DCG biogenesis. These cells contain unusually enlarged DCGs, which are assembled in compartments that also form secreted nanovesicles called exosomes. We demonstrate that known conserved regulators of DCG biogenesis, including the small G-protein Arf1 and the coatomer complex AP-1, play key roles in making SC DCGs. Using real-time imaging, we find that the aggregation events driving DCG biogenesis are accompanied by a change in the membrane-associated small Rab GTPases which are major regulators of membrane and protein trafficking in the secretory and endosomal systems. Indeed, a transition from trans-Golgi Rab6 to recycling endosomal protein Rab11, which requires conserved DCG regulators like AP-1, is essential for DCG and exosome biogenesis. Our data allow us to develop a model for DCG biogenesis that brings together several previously disparate observations concerning this process and highlights the importance of communication between the secretory and endosomal systems in controlling regulated secretion.

DsbA-L deletion attenuates LPS-induced acute kidney injury by modulating macrophage polarization

Disulfide bond A oxidoreductase-like protein (DsbA-L) drives acute kidney injury (AKI) by directly upregulating the expression of voltage-dependent anion-selective channels in proximal tubular cells. However, the role of DsbA-L in immune cells remains unclear. In this study, we used an LPS-induced AKI mouse model to assess the hypothesis that DsbA-L deletion attenuates LPS-induced AKI and explore the potential mechanism of DsbA-L action. After 24 hours of LPS exposure, the DsbA-L knockout group exhibited lower serum creatinine levels compared to the WT group. Furthermore, peripheral levels of the inflammatory cytokine IL-6 were decreased. Transcriptomic data analysis revealed a significant down-regulation in the IL-17 and tumor necrosis factor pathways in DsbA-L knockout mice following LPS induction. Metabolomic analysis suggested that arginine metabolism was significantly different between the WT and DsbA-L knockout groups after LPS treatment. Notably, the M1 polarization of macrophages in the kidneys of DsbA-L knockout AKI mice was significantly reduced. Expression of the transcription factors NF-κB and AP-1 was downregulated after DsbA-L knockout. Our results suggest that DsbA-L regulates LPS-mediated oxidative stress, promotes M1 polarization of macrophages, and induces expression of inflammatory factors via the NF-κB/AP-1 pathway.

The selective activator protein-1 inhibitor T-5224 regulates the IRF4/MYC axis and exerts cooperative antimyeloma activity with bortezomib

The activating protein-1 (AP-1) transcription factors (TFs) have been associated with many different cancer types and are promising therapeutic targets in logical malignancies. However, the mechanisms of their role in multiple myeloma (MM) remain elusive. The present study determined and compared the mRNA and protein expression levels of the AP-1 family member JunB in CD138+ mononuclear cells from MM patients and healthy donors. Herein, we investigated the effect of T-5224, an inhibitor of JUN/AP-1, on MM. We found that the cytotoxicity of T-5224 toward myeloma is due to its ability to induce cell apoptosis, inhibit proliferation, and induce cell cycle arrest by increasing the levels of cleaved caspase3/7 and concomitantly inhibiting the IRF4/MYC axis. We also noticed that siJunB-mediated deletion of JunB/AP-1 enhanced MM cell apoptosis and affected cell proliferation. The software PROMO was used in the present study to predict the AP-1 TF that may bind the promoter region of IRF4. We confirmed the correlation between JunB/AP-1 and IRF4. Given that bortezomib (BTZ) facilitates IRF4 degradation in MM cells, we applied combination treatment of BTZ with T-5224. T-5224 and BTZ exerted synergistic effects, and T-5224 reversed the effect of BTZ on CD138+ primary resistance in MM cells, in part due to suppression of the IRF4/MYC axis. Our results suggest that targeting AP-1 TFs is a promising therapeutic strategy for MM. Additionally, targeting both AP-1 and IRF4 with T-5224 may be a synergistic therapeutic strategy for this clinically challenging subset of MM.

Antioxidant and phytometabolite profiles of ethanolic extract from the cascara pulp of Coffea arabica collected from Gayo Highland: A study for potential anti-photoaging agent

Background: As the most abundant coffee by-product, cascara pulp has been considered a good source of antioxidants which could be used to prevent photoaging. The aim of this study was to determine the phytometabolite profiles, antioxidant and photoaging properties of the ethanolic extract of Coffea arabica cascara pulp. Methods: Ethanolic maceration was performed on the fine powder of C. arabica cascara pulp collected from Gayo Highland, Aceh Province, Indonesia. The filtrate obtained was evaluated for its 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, total phenolic content (TPC), and total flavonoid content (TFC). The phytometabolite profiling was conducted qualitatively using reagents and quantitatively using gas chromatography-mass spectroscopy (GC-MS). The potential of the cascara pulp phytometabolites in inhibiting activator protein-1 (AP-1) was evaluated through molecular docking. Results: The extract had TPC and TFC of 2.04 mg gallic acid equivalent/g extract and 91.81 mg quercetin equivalent/g extract, respectively. The half-maximal inhibitory concentration (IC 50) for the DPPH inhibition reached as low as 9.59 mg/L. Qualitative phytocompound screening revealed the presence of alkaloids, saponins, tannins, flavonoids, steroids, quinones, polyphenols, and triterpenoids. GC-MS revealed the extract containing 5-hydroxy-methylfurfural (22.31%); 2,5-dimethyl-4-hydroxy-3(2H)-furanone (0.74%); and caffeine (21.07%), which could form interaction with AP-1 with binding energies of -172.8, -150.8, and -63.188 kJ/mol, respectively. Conclusion: Ethanolic extract from C. arabica cascara pulp potentially have anti-photoaging properties which is worthy for further investigations in the future.

Genomic Profiling of the Craniofacial Ossifying Fibroma by Next-Generation Sequencing

BACKGROUND

Ossifying fibroma (OF) of the craniofacial skeleton is a fibro-osseous lesion characterized by various patterns of bone formation in a cellular fibroblastic stroma. The molecular landscape of OF remains mostly unknown. There are a few known pathogenic abnormalities in OF, including HRPT2 mutations in conventional OF and SATB2 translocations in juvenile psammomatoid OF. On the other hand, conflicting reports exist regarding MDM2 gene amplification and chromosomal copy number alterations (CNA) in OF.

METHODS

Surgically removed biopsies and curettage specimens from OF patients were obtained. Clinical, radiographic, and pathologic features of tumors were reviewed. Genomic DNA was extracted from formalin-fixed, paraffin-embedded blocks of tumor tissue. Capture-based DNA next-generation sequencing targeting the coding regions 529 cancer genes and select introns was performed.

RESULTS

We identified 17 OF cases from 8 male and 8 female patients with mean age of 22 years (range 1-58 years). Nine case occurred in the gnathic bones and 8 in the extragnathic craniofacial bones. These cases included 3 juvenile psammomatoid OF, 6 conventional OF and 8 juvenile trabecular OF. Large-scale CNAs were present in 6 of 17 cases. Seven cases (41%) had focal amplifications including FOSB (n = 2, 11%), FOS (n = 4, 23%), COL1A1 (n = 4, 23%) and TBX3 (n = 5, 29%). Three cases (17%) had pathogenic CDC73 mutations. No cases showed focal MDM2 amplification.

CONCLUSIONS

Here, we provided a comprehensive molecular characterization of OF that reveals a heterogeneous genetic profile with occasional large-scale CNAs (n = 6, 35%). FOS, FOSB, and TBX3 genes that regulate AP-1 transcriptional complex are frequently altered in OF (n = 7, 41%), chiefly in juvenile trabecular OF. These genes encode transcription factors that act as downstream effectors of the MAP kinase signaling pathway. MDM2 amplification is an exceedingly rare event in OF, if present at all, so identification of this event should continue to raise concern for low-grade gnathic osteosarcoma. In summary, our findings suggest that OF represents a heterogeneous group of tumors at the genetic level but dysregulation of the AP-1 pathway may play a role in pathogenesis of juvenile trabecular OF.

Streptolysin S induces pronounced calcium-ion influx-dependent expression of immediate early genes encoding transcription factors

Anginosus group streptococci (AGS) are opportunistic human pathogens of the oral cavity. The β-hemolytic subgroup of Streptococcus anginosus subsp. anginosus secretes streptolysin S (SLS) and exhibits not only hemolytic activity but also cytotoxicity toward cultured human cell lines. However, the detailed mechanism of action of SLS and the cellular responses of host cells have not yet been fully clarified. To determine the pathogenic potential of SLS-producing β-hemolytic S. anginosus subsp. anginosus, the SLS-dependent response induced in the human oral squamous cell carcinoma HSC-2 cells was investigated to determine the pathogenic potential of SLS-producing β-hemolytic S. anginosus subsp. anginosus. This study revealed that the Ca2+ influx and the expression of immediate early genes (IEGs) encoding transcription factors such as early growth responses (EGRs) and activator protein-1 (AP-1) were greatly increased in HSC-2 cells incubated with the culture supernatant of SLS-producing β-hemolytic S. anginosus subsp. anginosus. Moreover, this SLS-dependent increase in expression was significantly suppressed by Ca2+ chelation, except for jun. These results suggest that SLS caused Ca2+ influx into the cells following greatly enhanced expression of IEG-encoding transcription factors. The results of this study may help in understanding the pathogenicity of SLS-producing AGS.

Exploitation of ATP-sensitive potassium ion (KATP) channels by HPV promotes cervical cancer cell proliferation by contributing to MAPK/AP-1 signalling

Persistent infection with high-risk human papillomaviruses (HPVs) is the causal factor in multiple human malignancies, including >99% of cervical cancers and a growing proportion of oropharyngeal cancers. Prolonged expression of the viral oncoproteins E6 and E7 is necessary for transformation to occur. Although some of the mechanisms by which these oncoproteins contribute to carcinogenesis are well-characterised, a comprehensive understanding of the signalling pathways manipulated by HPV is lacking. Here, we present the first evidence to our knowledge that the targeting of a host ion channel by HPV can contribute to cervical carcinogenesis. Through the use of pharmacological activators and inhibitors of ATP-sensitive potassium ion (KATP) channels, we demonstrate that these channels are active in HPV-positive cells and that this activity is required for HPV oncoprotein expression. Further, expression of SUR1, which forms the regulatory subunit of the multimeric channel complex, was found to be upregulated in both HPV+ cervical cancer cells and in samples from patients with cervical disease, in a manner dependent on the E7 oncoprotein. Importantly, knockdown of SUR1 expression or KATP channel inhibition significantly impeded cell proliferation via induction of a G1 cell cycle phase arrest. This was confirmed both in vitro and in in vivo tumourigenicity assays. Mechanistically, we propose that the pro-proliferative effect of KATP channels is mediated via the activation of a MAPK/AP-1 signalling axis. A complete characterisation of the role of KATP channels in HPV-associated cancer is now warranted in order to determine whether the licensed and clinically available inhibitors of these channels could constitute a potential novel therapy in the treatment of HPV-driven cervical cancer.

Flubendazole inhibits PD-1 and suppresses melanoma growth in immunocompetent mice

BACKGROUND

Immune checkpoint inhibitor therapy has revolutionized the clinical management of a diverse range of cancer types, including advanced cutaneous melanoma. While immunotherapy targeting the PD-1/PD-L1 system has become standard of care, overall response rates remain unsatisfactory for most patients and there are no approved small molecule inhibitors of the PD-1/PD-L1 system. Flubendazole (FLU) is an anthelmintic that has been used to treat worm infections in humans and animals for decades.

METHODS

Here we tested the anti-cancer activity of systemically delivered FLU with suppression of PD-1 in immunocompetent mice.

RESULTS

In C57BL/6J mice bearing subcutaneous B16F10 melanoma, FLU reduced both tumor growth and PD-1 protein levels without affecting levels of PD-L1. FLU's suppression of PD-1 was accompanied by increased CD3+ T cell infiltration. Western blotting with extracts from human Jurkat T cells showed that FLU inhibited PD-1 protein expression, findings confirmed by flow cytometry. To gain mechanistic insights on FLU's ability to suppress PD-1 protein levels, we performed bulk RNA sequencing on extracts of Jurkat T cells exposed to the benzimidazole for 4 h. From a pool of 14,475 genes there were 1218 differentially-expressed genes; 687 with increased expression and 531 with decreased expression. Among the genes induced by FLU was the AP-1 family member, JUN and surprisingly, pdcd1. KEGG pathway analysis showed FLU up-regulated genes over-represented in multiple pathways (p < 0.01), the top hit being amoebiasis. FLU also affected the expression of genes in cancer-associated pathways, both through down-regulation and up-regulation. Gene set enrichment analysis revealed a large number of immunological signature gene sets correlated with FLU treatment, including gene sets associated with T cell differentiation, proliferation and function. The AP-1 inhibitor T5224 rescued PD-1 protein expression from inhibition by FLU.

CONCLUSION

This study is the first to show that FLU can inhibit melanoma growth with PD-1 suppression in immunocompetent mice.

Microtubule Acetylation-Specific Inhibitors Induce Cell Death and Mitotic Arrest via JNK/AP-1 Activation in Triple-Negative Breast Cancer Cells

Microtubule acetylation has been proposed as a marker of highly heterogeneous and aggressive triple-negative breast cancer (TNBC). The novel microtubule acetylation inhibitors GM-90257 and GM-90631 (GM compounds) cause TNBC cancer cell death but the underlying mechanisms are currently unknown. In this study, we demonstrated that GM compounds function as anti-TNBC agents through activation of the JNK/AP-1 pathway. RNA-seq and biochemical analyses of GM compound-treated cells revealed that c-Jun N-terminal kinase (JNK) and members of its downstream signaling pathway are potential targets for GM compounds. Mechanistically, JNK activation by GM compounds induced an increase in c-Jun phosphorylation and c-Fos protein levels, thereby activating the activator protein-1 (AP-1) transcription factor. Notably, direct suppression of JNK with a pharmacological inhibitor alleviated Bcl2 reduction and cell death caused by GM compounds. TNBC cell death and mitotic arrest were induced by GM compounds through AP-1 activation in vitro. These results were reproduced in vivo, validating the significance of microtubule acetylation/JNK/AP-1 axis activation in the anti-cancer activity of GM compounds. Moreover, GM compounds significantly attenuated tumor growth, metastasis, and cancer-related death in mice, demonstrating strong potential as therapeutic agents for TNBC.

Characterization of a Filamentous Phage, Vaf1, from Vibrio alginolyticus AP-1

Filamentous phages are ubiquitously distributed in the global oceans. However, little is known about their biological contribution to their host's genetic and phenotypic diversity. In this study, a filamentous phage, Vaf1, was isolated and characterized from the emerging marine pathogen strain Vibrio alginolyticus AP-1. We explored the effects of the resident phage Vaf1 on the host physiology under diverse conditions by precisely deleting the entire phage Vaf1. Our results demonstrate that the presence of phage Vaf1 significantly increased biofilm formation, swarming motility, and contact-dependent competition. Furthermore, the gene expression profile suggests that several phage genes were upregulated in response to low-nutrient conditions. Unexpectedly, an in vivo study of zebrafish shows that fish infected with strain ΔVaf1 survived longer than those infected with wild-type strain AP-1, indicating that Vaf1 contributes to the virulence of V. alginolyticus. Together, our results provide direct evidence for the effect of Vaf1 phage-mediated phenotypic changes in marine bacteria V. alginolyticus. This further emphasizes the impressive complexity and diversity that filamentous phage-host interactions pose and the challenges associated with bacterial disease control in marine aquaculture. IMPORTANCE Non-lytic filamentous phages can replicate without killing their host, establishing long-term persistence within the bacterial host. In contrast to the well-studied CTXφ phage of the human-pathogenic Vibrio cholerae, little is known about the filamentous phage Vaf1 and its biological role in host fitness. In this study, we constructed a filamentous phage-deleted strain, ΔVaf1, and provided direct evidence on how an intact phage, φVaf1, belonging to the family Inoviridae, helps the bacterial host AP-1 to overcome adverse environmental conditions. Our results likely open new avenues for fundamental studies on how filamentous phage-host interactions regulate different aspects of Vibrio cell behaviors.

How to initiate tissue regeneration by generating mutually exclusive cell states

A healing wound is made of cells that paused proliferation and secrete mitogenic factors and cells that proliferate to replace those lost to cell death. A new study in PLOS Biology describes how 2 conserved signaling pathways could repress each other to create these mutually exclusive cell states.

Investigation of the mechanism of Prunella vulgaris in treatment of papillary thyroid carcinoma based on network pharmacology integrated molecular docking and experimental verification

To analyze the molecular mechanism of Prunella vulgaris L. (PV) in the treatment of papillary thyroid carcinoma (PTC) by using network pharmacology combined with molecular docking verification. Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform database was used to predict the main active components of PV, Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform, PubChem, and Swiss Target Prediction databases were used to obtain the corresponding targets of all active components. Targets collected for PTC treatment through Gene Cards, Digest and Online Mendelian Inheritance in Man databases respectively. The Search Tool for the Retrieval of Interaction Gene/Protein database was used to obtain the interaction information between proteins, and the topology analysis and visualization were carried out through Cytoscape 3.7.2 software (https://cytoscape.org/). The R package cluster profiler was used for gene ontology and Kyoto encyclopedia of genes and genomes analysis. The "active ingredient-target-disease" network was constructed by using Cyto scape 3.7.2, and topological analysis was carried out to obtain the core compound. The molecular docking was processed by using Discovery Studio 2019 software, and the core target and active ingredient were verified. The inhibition rate was detected by CCK8 method. Western blot was used to detect the expression levels of kaempferol anti-PTC related pathway proteins. A total of 11 components and 83 corresponding targets in the component target network of PV, of which 6 were the core targets of PV in the treatment of PTC. It was showed that quercetin, luteolin, beta (β)-sitosterol, kaempferol may be the core components of PV in the treatment of PTC. vascular endothelial growth factor A, tumor protein p53, transcription factor AP-1, prostaglandin endoperoxidase 2, interleukin 6, and IL-1B may be important targets for the treatment of PTC. The main biological processes mainly including response to nutrient levels, response to xenobiotic stimulus, response to extracellular stimulus, external side of plasma membrane, membrane raft, membrane microdomain, serine hydrolase activity, serine-type endopeptidase activity, antioxidant activity, etc IL-17 signaling pathway, and PI3K-Akt signaling pathway may affect the recurrence and metastasis of PTC. Kaempferol may significantly reduce the activity of Papillary cells of human thyroid carcinoma bcpap cell lines cells compared with quercetin, luteolin, β-sitosterol. Kaempferol may reduce the protein expression levels of interleukin 6, vascular endothelial growth factor A, transcription factor AP-1, tumor protein p53, 1L-1B and prostaglandin endoperoxidase 2, respectively. PV has the characteristics of multi-components, multi-targets and multi- pathways in the treatment of PTC, which network pharmacology help to provides a theoretical basis for the screening of effective components of PV and further research.

A novel CDK8 inhibitor with poly-substituted pyridine core: Discovery and anti-inflammatory activity evaluation in vivo

As an ideal anti-inflammatory target, cyclin-dependent kinase 8 (CDK8) has gradually attracted the attention of researchers. CDK8 inhibition up-regulates Interleukin-10 (IL-10) expression by enhancing the transcriptional activity of activator protein-1 (AP-1), and augmenting IL-10 abundance is a viable strategy for the treatment of inflammatory bowel disease (IBD). In this research, through structure-based drug design and dominant fragment hybridization, a series of poly-substituted pyridine derivatives were designed and synthesized as CDK8 inhibitors. Ultimately, compound CR16 was identified as the best one, which exhibited good inhibitory activity against CDK8 (IC₅₀ = 74.4 nM). In vitro and in vivo studies indicated that CR16 could enhance the transcriptional activity of AP-1, augment the abundance of IL-10, and affect CDK8-related signaling pathways including TLR7/NF-κB/MAPK and IL-10-JAK1-STAT3 pathways. In addition, CR16 showed potent therapeutic effect in an animal model of IBD.

The Drinking Water and Swimming Pool Disinfectant Trichloroisocyanuric Acid Causes Chlorination Stress Enhancing Solar UV-Induced Inflammatory Gene Expression in AP-1 Transgenic SKH-1 Luciferase Reporter Mouse Skin

Freshwater sanitation and disinfection using a variety of chemical entities as chlorination agents is an essential public health intervention ensuring water safety for populations at a global scale. Recently, we have published our observation that the small molecule oxidant, innate immune factor and chlorination agent HOCl antagonize inflammation and photocarcinogenesis in murine skin exposed topically to environmentally relevant concentrations of HOCl. Chlorinated isocyanuric acid derivatives (including the chloramines trichloroisocyanuric acid [TCIC] and dichloroisocyanuric acid [DCIC]) are used worldwide as alternate chlorination agents serving as HOCl precursor and stabilizer compounds ensuring sustained release in aqueous environments including public water systems, recreational pools and residential hot tubs. Here, for the first time, we have examined the cutaneous TCIC-induced transcriptional stress response (in both an organotypic epidermal model and in AP-1 luciferase reporter SKH-1 mouse skin), also examining molecular consequences of subsequent treatment with solar ultraviolet (UV) radiation. Taken together, our findings indicate that cutaneous delivery of TCIC significantly enhances UV-induced inflammation (as profiled at the gene expression level), suggesting a heretofore unrecognized potential to exacerbate UV-induced functional and structural cutaneous changes. These observations deserve further molecular investigations in the context of TCIC-based freshwater disinfection with health implications for populations worldwide.

Role of c-Jun NH2 -terminal kinase-mediated mitogen-activated protein kinase pathway in response to pesticides in Apis cerana cerana

The mitogen-activated protein kinase (MAPK) cascade pathway plays an important role in regulating stress responses. The function of the c-Jun NH₂ -terminal kinase (JNK), a component of the MAPK cascade pathway, in Apis cerana cerana (Acc) remains unclear. Here, JNK was isolated and identified from Acc. Bioinformatics analyses revealed there is a typical serine/threonine protein kinase catalytic domain in the AccJNK protein. An expression profile analysis showed that AccJNK was significantly induced by pesticide treatments. To further explore the functional mechanisms of AccJNK, a yeast 2-hybrid screen was performed, activator protein-1 (AP-1) was screened as the interaction partner of AccJNK, and the interaction relationship was further verified by pull-down assay. Quantitative real-time polymerase chain reaction showed the expression pattern of AccAP-1 was similar to that of AccJNK. After a knockdown of AccJNK or AccAP-1 by RNA interference, the survival rate of Acc after pesticide treatments increased. Additionally, the expression levels of antioxidant-related genes and the activities of antioxidant enzymes increased, suggesting that the knockdown of AccJNK or AccAP-1 increased the antioxidant capacity of bees. Our study revealed that the JNK-mediated MAPK pathway responds to pesticide stress by altering the antioxidant capacity of Acc.

Clearance of HIV-1 or SIV reservoirs by promotion of apoptosis and inhibition of autophagy: Targeting intracellular molecules in cure-directed strategies

The reservoirs of the HIV display cellular properties resembling long-lived immune memory cells that could be exploited for viral clearance. Our interest in developing a cure for HIV stems from the studies of immunologic memory against infections. We and others have found that long-lived immune memory cells employ prosurvival autophagy and antiapoptotic mechanisms to protect their longevity. Here, we describe the rationale for the development of an approach to clear HIV-1 by selective elimination of host cells harboring replication-competent HIV (SECH). While reactivation of HIV-1 in the host cells with latency reversing agents (LRAs) induces viral gene expression leading to cell death, LRAs also simultaneously up-regulate prosurvival antiapoptotic molecules and autophagy. Mechanistically, transcription factors that promote HIV-1 LTR-directed gene expression, such as NF-κB, AP-1, and Hif-1α, can also enhance the expression of cellular genes essential for cell survival and metabolic regulation, including Bcl-xL, Mcl-1, and autophagy genes. In the SECH approach, we inhibit the prosurvival antiapoptotic molecules and autophagy induced by LRAs, thereby allowing maximum killing of host cells by the induced HIV-1 proteins. SECH treatments cleared HIV-1 infections in humanized mice in vivo and in HIV-1 patient PBMCs ex vivo. SECH also cleared infections by the SIV in rhesus macaque PBMCs ex vivo. Research efforts are underway to improve the efficacy and safety of SECH and to facilitate the development of SECH as a therapeutic approach for treating people with HIV.

Additional supplementation of sulfur-containing amino acids in the diets improves the intestinal health of turbot fed high-lipid diets

An eight-week feeding trial was conducted to investigate the effects of diets supplemented with three sulfur-containing amino acids (SAA), namely, methionine, cysteine, and taurine, on the intestinal health status of juvenile turbot (Scophthalmus maximus) fed high-lipid diets. Four diets were formulated, namely, a high-lipid control diet (16% lipid, HL) and three SAA-supplemented diets, which were formulated by supplementing 1.5% methionine (HLM), 1.5% cysteine (HLC), and 1.5% taurine (HLT) into the HL control diet, respectively. Each diet was assigned to triplicate tanks, and each tank was stocked with 30 juvenile fish (appr. initial weight, 8 g). The histological and morphometric results showed that dietary SAA supplementation obviously improved the intestinal morphology and integrity, in particular as reflected by higher height of microvilli and mucosal folds. Dietary SAA supplementation, in particular cysteine, up-regulated the gene expression of mucin-2 and tight junction proteins (ZO-1, Tricellilun and JAM). Dietary SAA supplementation remarkably down-regulated the gene expression of apoptosis-related factors such as p38, JNK, and Bax, expression of pro-inflammatory factors (e.g., NF-κB, AP-1 IL-1β, IL-8, and TNF-α). SAA supplementation resulted in higher antioxidative abilities in the intestine. Additionally, dietary SAA supplementation largely altered the communities of intestinal microbiota. Compared with the HL group, higher relative abundance of potential beneficial bacteria, and lower relative abundance of opportunistic pathogens were observed in SAA-supplemented groups. Dietary taurine supplementation significantly increased the relative abundance of Ligilactobacillus (in particular Lactobacillus murinus) and Limosilactobacillus (especially Lactobacillus reuteri). In conclusion, dietary sulfur-containing amino acids supplementation have promising potential in ameliorating the intestinal inflammation of turbot fed high-lipid diets. Especially dietary cysteine and taurine supplementation have more positive effects on the communities of the intestinal microbiota of turbot.

Basolateral Sorting of the Sodium/Iodide Symporter Is Mediated by Adaptor Protein 1 Clathrin Adaptor Complexes

Background: The sodium/iodide symporter (NIS) is a transmembrane protein located on the basolateral membrane of thyrocytes. Despite its physiological and clinical relevance, little is known about the mechanisms that mediate NIS subcellular sorting. In the present study, we examined NIS basolateral trafficking in vitro using non-thyroid and thyroid epithelial cells. Methods: Immunofluorescence and Western blotting were performed to analyze NIS subcellular location and function in cells grown in monolayers under unpolarized and/or polarized conditions. Strategic NIS residues were mutated, and binding of NIS to clathrin adaptor complexes was determined by immunoprecipitation. Results: We show that NIS reaches the plasma membrane (PM) through a thyrotropin-dependent mechanism 24 hours after treatment with the hormone. We demonstrate that NIS basolateral trafficking is a clathrin-mediated mechanism, in which the clathrin adaptor complexes AP-1 (A and B) sort NIS from the trans-Golgi network (TGN) and recycling endosomes (REs). Specifically, we show that the AP-1B μ1 subunit controls NIS basolateral sorting through common REs. In its absence, NIS is apically missorted but remains functional. Additionally, direct NIS basolateral transport from the TGN to the basolateral membrane is mediated by AP-1A through clathrin-coated vesicles that also carry the transferrin receptor. Loss of the μ1 subunit of AP-1A is functionally compensated by AP-1B. Furthermore, loss of both subunits diminishes NIS trafficking to the PM. Finally, we demonstrate that AP-1A binds to the L121 and LL562/563 residues on NIS, whereas AP-1B binds to L583. Conclusions: Our findings highlight the novel involvement of the clathrin-coated machinery in basolateral NIS trafficking. Given that AP-1A expression is reduced in tumors, and its expression correlates with that of NIS, these findings will help uncover new targets in thyroid cancer treatment.

Single-cell sequencing of PBMC characterizes the altered transcriptomic landscape of classical monocytes in BNT162b2-induced myocarditis

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been the most dangerous threat to public health worldwide for the last few years, which led to the development of the novel mRNA vaccine (BNT162b2). However, BNT162b2 vaccination is known to be associated with myocarditis. Here, as an attempt to determine the pathogenesis of the disease and to develop biomarkers to determine whether subjects likely proceed to myocarditis after vaccination, we conducted a time series analysis of peripheral blood mononuclear cells of a patient with BNT162b2-induced myocarditis. Single-cell RNA sequence analysis identified monocytes as the cell clusters with the most dynamic changes. To identify distinct gene expression signatures, we compared monocytes of BNT162b2-induced myocarditis with monocytes under various conditions, including SARS-CoV-2 infection, BNT162b2 vaccination, and Kawasaki disease, a disease similar to myocarditis. Representative changes in the transcriptomic profile of classical monocytes include the upregulation of genes related to fatty acid metabolism and downregulation of transcription factor AP-1 activity. This study provides, for the first time, the importance of classical monocytes in the pathogenesis of myocarditis following BNT162b2 vaccination and presents the possibility that vaccination affects monocytes, further inducing their differentiation and infiltration into the heart.

Research into the mechanism of intervention of SanQi in endometriosis based on network pharmacology and molecular docking technology

BACKGROUND

By using network pharmacology and molecular docking technology, we have explored the mechanism of action of Sanqi in the treatment of endometriosis (EMS), in order to provide reference for clinical studies of Chinese medicine treatment of Ems and Chinese medicine pharmacology.

METHODS

There are 123 intersecting targets between the active ingredients of Sanqi and disease targets. In the Protein-Protein Interaction network, Jun proto-oncogene, AP-1 transcription factor subunit, tumor necrosis factor, interleukin 6, etc., are the core proteins. The top 20 genes ranked by degree have been analyzed according to the Kyoto Encyclopedia of Genes and Genomes pathway and Gene Ontology analysis, and 20 pathways have been identified.

RESULTS

On the Kyoto Encyclopedia of Genes and Genomes pathway, the most important part is the phosphatidylinositol 3'-kinase-Akt signaling pathway, and on the Gene Ontology pathway, it is the Heme binding. The top 3 targets docked to quercetin have a certain affinity when it is docked to their degree value. Among the chemical components of Sanqi, quercetin has the most targets, suggesting that it may play a major role in the treatment of EMS.

CONCLUSION

The results of molecular docking provide further evidence of the potential role of Sanqi for EMS. Overall, our study provides a new direction for the treatment of EMS and provides the basis for Sanqi as a drug for the treatment of EMS.

In vivo and in vitro toxicity of a stainless-steel aerosol generated during thermal spray coating

Thermal spray coating is an industrial process in which molten metal is sprayed at high velocity onto a surface as a protective coating. An automated electric arc wire thermal spray coating aerosol generator and inhalation exposure system was developed to simulate an occupational exposure and, using this system, male Sprague-Dawley rats were exposed to stainless steel PMET720 aerosols at 25 mg/m³ × 4 h/day × 9 day. Lung injury, inflammation, and cytokine alteration were determined. Resolution was assessed by evaluating these parameters at 1, 7, 14 and 28 d after exposure. The aerosols generated were also collected and characterized. Macrophages were exposed in vitro over a wide dose range (0-200 µg/ml) to determine cytotoxicity and to screen for known mechanisms of toxicity. Welding fumes were used as comparative particulate controls. In vivo lung damage, inflammation and alteration in cytokines were observed 1 day post exposure and this response resolved by day 7. Alveolar macrophages retained the particulates even after 28 day post-exposure. In line with the pulmonary toxicity findings, in vitro cytotoxicity and membrane damage in macrophages were observed only at the higher doses. Electron paramagnetic resonance showed in an acellular environment the particulate generated free radicals and a dose-dependent increase in intracellular oxidative stress and NF-kB/AP-1 activity was observed. PMET720 particles were internalized via clathrin and caveolar mediated endocytosis as well as actin-dependent pinocytosis/phagocytosis. The results suggest that compared to stainless steel welding fumes, the PMET 720 aerosols were not as overtly toxic, and the animals recovered from the acute pulmonary injury by 7 days.

Ets21C sustains a pro-regenerative transcriptional program in blastema cells of Drosophila imaginal discs

An important unanswered question in regenerative biology is to what extent regeneration is accomplished by the reactivation of gene regulatory networks used during development versus the activation of regeneration-specific transcriptional programs. Following damage, Drosophila imaginal discs, the larval precursors of adult structures, can regenerate missing portions by localized proliferation of damage-adjacent tissue. Using single-cell transcriptomics in regenerating wing discs, we have obtained a comprehensive view of the transcriptome of regenerating discs and identified two regeneration-specific cell populations within the blastema, Blastema1 and Blastema2. Collectively, these cells upregulate multiple genes encoding secreted proteins that promote regeneration including Pvf1, upd3, asperous, Mmp1, and the maturation delaying factor Ilp8. Expression of the transcription factor Ets21C is restricted to this regenerative secretory zone; it is not expressed in undamaged discs. Ets21C expression is activated by the JNK/AP-1 pathway, and it can function in a type 1 coherent feedforward loop with AP-1 to sustain expression of downstream genes. Without Ets21C function, the blastema cells fail to maintain the expression of a number of genes, which leads to premature differentiation and severely compromised regeneration. As Ets21C is dispensable for normal development, these observations indicate that Ets21C orchestrates a regeneration-specific gene regulatory network. We have also identified cells resembling both Blastema1 and Blastema2 in scribble tumorous discs. They express the Ets21C-dependent gene regulatory network, and eliminating Ets21C function reduces tumorous growth. Thus, mechanisms that function during regeneration can be co-opted by tumors to promote aberrant growth.

BCL10 regulates the production of proinflammatory cytokines by activating MAPK-NF-κB/Rel signaling pathway in oysters

B cell lymphoma/leukemia 10 (BCL10) is an important member of the caspase recruitment domain-containing (CARD) protein family, which plays crucial roles in mediating the host inflammatory response. In the present study, a BCL10 homologue was identified from Pacific oyster Crassostrea gigas (designed as CgBCL10). The full length cDNA of CgBCL10 was of 897 bp with an open reading frame of 522 bp encoding a polypeptide of 174 amino acids containing a classical CARD domain. The deduced amino acid sequence of CgBCL10 shared low similarity with the previously identified BCL10s from other species. In the phylogenetic tree, CgBCL10 was firstly clustered with CvBCL10 from Crassostrea virginica and then assigned into the branch of invertebrate BCL10s. The mRNA transcripts of CgBCL10 were highly expressed in gonad, gill, adductor muscle, and haemocytes. After Vibrio splendidus stimulation, the mRNA expression level of CgBCL10 in haemocytes increased significantly (p < 0.01) at 24, 72 and 96 h. In CgBCL10-RNAi oysters, the phosphorylation level of mitogen-activated protein kinases (MAPKs), nuclear translocation of NF-κB/Rel and activator protein-1 (AP-1) in haemocytes were inhibited, and the mRNA expressions of inflammatory cytokines including CgIL17-1, CgIL17-2, CgIL17-3, CgIL17-6 and CgTNF all decreased significantly (p < 0.01) at 12 h after V. splendidus stimulation. These results suggested that CgBCL10 regulated the expression of inflammatory cytokines by activating MAPK kinase, and nuclear translocation of NF-κB/Rel and AP-1 to defense pathogen.

Silencing of FOS-like antigen 1 represses restenosis via the ERK/AP-1 pathway in type 2 diabetic mice

Restenosis is a major limiting factor for a successful outcome in type 2 diabetes (T2D) patients undergoing percutaneous coronary intervention (PCI). The aim of this study is to explore the role and regulatory mechanism of FOS-like antigen 1 (FOSL1) in restenosis in T2D. A T2D with restenosis mouse model was established by the combination of high-fat diet and streptozotocin injection and by wire-injury. High glucose (HG)-treated vascular smooth muscle cells (VSMCs) were used to mimic T2D in vitro. The results of quantitative real time PCR and western blotting demonstrated that the expression of FOSL1 was increased not only in T2D mice or HG-induced VSMCs, but also in T2D mice that underwent wire-injury. HE staining revealed that FOSL1 knockdown significantly reduced the intimal/media ratio of T2D mice after wire-injury. Silencing of FOSL1 reversed the promoting effects of HG treatment on viability, migration and inflammation reactions, and the inhibiting effect on the apoptosis of VSMCs. Inhibition of ERK/AP-1 pathway obtained similar patterns in HG-induced VSMCs. The activation of ERK/AP-1 pathway reversed the influence of FOSL1 knockdown on HG-induced VSMCs. Our findings indicate that silencing of FOSL1 may suppress restenosis via regulation of the ERK/AP-1 pathway in T2D mice, pointing out a potential therapeutic target to prevent restenosis in T2D.

Ultrasmall Prussian blue nanoparticles attenuate UVA-induced cellular senescence in human dermal fibroblasts via inhibiting the ERK/AP-1 pathway

Ultraviolet A (UVA) irradiation can induce cellular senescence and cause skin photoaging, which is mainly driven by the excessive production of reactive oxygen species (ROS). Emerging studies have focused on new strategies for the prevention of skin photoaging. Ultrasmall Prussian blue nanoparticles (USPBNPs) demonstrate an intensive ability to scavenge ROS as nanozymes and exhibit great potential in the treatment of ROS-related diseases. Our goal was to investigate the anti-senescent role of USPBNPs against UVA-induced premature senescence in human dermal fibroblasts (HDFs). Our results showed that the activation of senescence-associated β-galactosidase (SA-β-gal) and the arrest of the cell cycle induced by UVA radiation in HDFs were significantly inhibited by pretreatment of USPBNPs (1 μg ml^-1). Furthermore, USPBNPs downregulated the expression of DNA damage marker γH2AX and inhibited the secretion of senescence-associated secretory phenotypes (SASP) including IL-6, TNF-α and matrix metalloproteinases (MMPs). In addition, we found that the antiphotoaging effect of USPBNPs involved the scavenging of ROS as well as the inhibition of the ERK/AP-1 pathway. In conclusion, USPBNPs exhibited great potential to become novel anti-photoaging agents by alleviating UVA-induced cellular senescence and thus delaying the process of skin photoaging.

Activator protein-1 mediated CYP6ER1 overexpression in the clothianidin resistance of Nilaparvata lugens (Stål)

BACKGROUND

Nilaparvata lugens, a destructive rice pest in Asia, has developed resistance to many insecticides, including the neonicotinoid clothianidin. CYP6ER1 plays an important role in N. lugens resistant to clothianidin, but only limited information on the transcriptional regulation of CYP6ER1 overexpression in clothianidin resistance is available.

RESULTS

In this study, the transcription factor activator protein 1 (AP-1) was found to be overexpressed in a clothianidin-resistant strain of N. lugens and several field resistant populations. RNA interference-mediated silencing of NlAP-1 significantly decreased CYP6ER1 expression and increased the susceptibility of N. lugens to clothianidin. Additionally, NlAP-1 was highly expressed in egg and adult stages, and in midguts, and NlAP-1 was upregulated and induced to a greater extent in the clothianidin-resistant strain after exposure to clothianidin. Finally, dual-luciferase reporter assays confirmed the interaction between NlAP-1 and the two predicted binding sites in the CYP6ER1 promoter.

CONCLUSION

NlAP-1 bound the -1388 to -1208-bp region of the CYP6ER1 promoter, enhancing its activity and then regulate the expression of CYP6ER1. These findings enhance our knowledge of the transcriptional regulation of the P450 genes that mediate insecticide resistance in insect pests. © 2021 Society of Chemical Industry.

The Roles of Epinephelus coioides miR-122 in SGIV Infection and Replication

In mammals, mature miR-122 is 22 nucleotides long and can be involved in regulating a variety of physiological and biological pathways. In this study, the expression profile and effects of grouper Epinephelus coioides miR-122 response to Singapore grouper iridovirus (SGIV) infection were investigated. The sequences of mature microRNAs (miRNAs) from different organisms are highly conserved, and miR-122 from E. coioides exhibits high similarity to that from mammals and other fish. The expression of miR-122 was up-regulated during SGIV infection. Up-regulation of miR-122 could significantly enhance the cytopathic effects (CPE) induced by SGIV, the transcription levels of viral genes (MCP, VP19, LITAF and ICP18), and viral replication; reduce the expression of inflammatory factors (TNF-a, IL-6, and IL-8), and the activity of AP-1 and NF-κB, and miR-122 can bind the target gene p38α MAPK to regulate the SGIV-induced cell apoptosis and the protease activity of caspase-3. The results indicated that SGIV infection can up-regulate the expression of E. coioides miR-122, and up-regulation of miR-122 can affect the activation of inflammatory factors, the activity of AP-1 and NF-κB, and cell apoptosis to regulate viral replication and proliferation.

Human RAP1 specifically protects telomeres of senescent cells from DNA damage

Repressor/activator protein 1 (RAP1) is a highly evolutionarily conserved protein found at telomeres. Although yeast Rap1 is a key telomere capping protein preventing non-homologous end joining (NHEJ) and consequently telomere fusions, its role at mammalian telomeres in vivo is still controversial. Here, we demonstrate that RAP1 is required to protect telomeres in replicative senescent human cells. Downregulation of RAP1 in these cells, but not in young or dividing pre-senescent cells, leads to telomere uncapping and fusions. The anti-fusion effect of RAP1 was further explored in a HeLa cell line where RAP1 expression was depleted through an inducible CRISPR/Cas9 strategy. Depletion of RAP1 in these cells gives rise to telomere fusions only when telomerase is inhibited. We further show that the fusions triggered by RAP1 loss are dependent upon DNA ligase IV. We conclude that human RAP1 is specifically involved in protecting critically short telomeres. This has important implications for the functions of telomeres in senescent cells.

Geranylgeranyl diphosphate synthase 1 knockout ameliorates ventilator-induced lung injury via regulation of TLR2/4-AP-1 signaling

OBJECTIVE

To investigate the role of geranylgeranyl diphosphate synthase 1 (GGPPS1) in ventilator-induced lung injury along with the underlying mechanism.

METHODS

A murine VILI model was induced by high-tidal volume ventilation in both wild-type and GGPPS1 knockout mice. GGPPS1 expression was detected in the bronchoalveolar lavage fluid (BALF) supernatants of acute respiratory distress syndrome (ARDS) patients and healthy volunteers, as well as in lung tissues and BALF supernatants of the VILI mice using enzyme-linked immunosorbent assay (ELISA), quantitative reverse transcription polymerase chain reaction (qRT-PCR), western bolt and immunohistochemical (IHC). The wet/dry ratio, total BALF proteins, and lung injury score were analyzed. The percentage of neutrophils was detected by flow cytometry and IHC. Inflammatory cytokine levels were measured by ELISA and qRT-PCR. The related expression of Toll-like receptor (TLR)2/4 and its downstream proteins was evaluated by western blot.

RESULTS

GGPPS1 in BALF supernatants was upregulated in ARDS patients and the VILI mice. Depletion of GGPPS1 significantly alleviated the severity of ventilator induced lung injury in mice. Total cell count, neutrophils and inflammatory cytokines (interleukin [IL]-6, IL-1β, IL-18 and tumor necrosis factor-α) levels in BALF were reduced after GGPPS1 depletion. Moreover, addition of exogenous GGPP in GGPPS-deficient mice significantly exacerbated the severity of ventilator induced lung injury as compared to the PBS treated controls. Mechanistically, the expression of TLR2/4, as well as downstream proteins including activator protein-1 (AP-1) was suppressed in lung tissues of GGPPS1-deficient mice.

CONCLUSION

GGPPS1 promoted the pathogenesis of VILI by modulating the TLR2/4-AP-1 signaling pathway, and GGPPS1 knockout significantly alleviated the lung injury and inflammation in the VILI mice.