CcPTGS2a-like gene-mediated NF-κB/ERK signaling regulation in the common carp (Cyprinus carpio).

Prostaglandin-endoperoxide synthase 2 (PTGS2), a common biological macromolecule, is pivotal for innate immunity and pathogen recognition. In this study, we identified and characterized a CcPTGS2a-like gene in the common carp (Cyprinus carpio) with an open reading frame (ORF) of 1821 bp and epidermal growth factor and peroxidase domains. Our multiple sequence analysis revealed high homology between the amino acid sequence of CcPTGS2a-like and those of its homologs in other fish. CcPTGS2a-like mRNA and protein expressions were significantly upregulated in the spleen, head kidney, liver, and gill tissues upon exposure to Aeromonas hydrophila stimulation. CcPTGS2a-like protein recognized the conserved bacterial surface components and exhibited detectable bacterial binding activity. CcPTGS2a-like overexpression before exposure to A. hydrophila notably enhanced the survival rate of common carp, concomitant with decreased bacterial burden. The NF-κB/ERK signaling pathway initiated the immune response in common carp upon infection with A. hydrophila. CcPTGS2a-like overexpression or interference in the head kidney and Epithelioma papulosum cyprinid cells could modulate the p-NF-κB (p-p-65), p-IκBα, and p-ERK1/2 levels as well as the IL-1ß and IL-6 mRNA expression. These results indicated potential CcPTGS2a-like involvement in the immune response of the common carp to bacterial infections through the NF-κB/ERK signaling pathway.

Apigenin suppresses the low oxaliplatin-induced epithelial-mesenchymal transition in oral squamous cell carcinoma cells via LINC00857.

Background: Apigenin is a natural flavonoid compound with proven antitumor activity. However, its precise underlying pharmacological mechanism remains unclear. Oxaliplatin (OXA) is commonly utilized for cancer treatment as a platinum-based chemotherapy drug. However, the utilization of low-dose OXA carries the risk of inducing epithelial-mesenchymal transition (EMT) in cancer cells and promoting tumor metastasis, thereby giving rise to potential side effects. The purpose of this study is to investigate the synergistic inhibitory effect of apigenin and OXA and its potential mechanism. Methods: HSC-3 cells of oral squamous carcinoma cells (OSCCs) were divided into control, apigenin-treated and co-treated groups. A wound healing assay was conducted to assess alterations in cellular motility and migration, an invasion assay was performed to assess invasiveness, and a three-dimensional culture assay was employed to evaluate angiogenic capacity. Cultured cells were utilized for total DNA extraction, followed by reverse transcription. Relative RNA levels were obtained, and quantitative polymerase chain reaction (qPCR) analysis was conducted to assess the efficiency of LINC00857 expression. Results: The administration of a low dose of OXA promoted the migratory, invasive, and angiogenic capabilities of HSC-3 cells, while also regulating EMT-associated molecular markers to facilitate the process of EMT. The inhibitory impact on OSCC proliferation was enhanced by the synergistic effect of apigenin and OXA. Furthermore, the tumor-promoting effects induced by low-dose OXA were notably suppressed through LINC00857. Conclusions: Evidence from this study indicates that apigenin can effectively suppress the metastasis of OSCC cancer cells induced by low-dose OXA through inhibiting the level of LINC00857, suggesting a promising therapeutic strategy.

Effect of Luhong formula on the cardiac rehabilitation of patients with chronic heart failure.

BACKGROUND: Current treatments for chronic heart failure (CHF) are therapeutically ineffective. The optimization of treatments for this disease needs to be explored and analyzed. AIM: To analyze the effect of using Luhong Formula in the cardiac rehabilitation of patients with CHF and its influence on cardiopulmonary function (CPF) and prognosis. METHODS: In total, 160 patients with CHF admitted between June 2022 and June 2023 were selected, including 75 receiving perindopril (control group) and 85 receiving Luhong Formula (research group). We conducted comparative analyses on the curative effects of traditional Chinese medicine (TCM) syndromes and cardiac function, CPF [oxygen consumption at the anaerobic threshold (VO2 AT) and at peak exercise (peak VO2)], echocardiographic indexes [left atrial volume index (LAVI), left ventricular muscle mass index (LVMI), left ventricular ejection fraction (LVEF)], and prognosis [major adverse cardiovascular events (MACEs) at 6 months follow-up]. RESULTS: The research group showed markedly higher curative effects of TCM syndromes and cardiac function than the control group. In addition, post-treatment VO2 AT, peak VO2, LVMI and LVEF in the research group were significantly higher, whereas LAVI was significantly lower, than those of the control group. Furthermore, fewer patients in the research group developed MACEs at the 6-month follow-up. CONCLUSION: Luhong Formula is more therapeutically effective than perindopril for the cardiac rehabilitation of patients with CHF, specifically in enhancing CPF and prognosis.

The molecular characterization of Rab11 and its immune roles in red swamp crayfish (Procambarus clarkii).

The Rab proteins primarily regulate vesicular transport between membrane-bound organelles and are important for innate immune. However, there is currently a lack of studies on crustaceans regarding Rab proteins, particularly core Rabs. We identified a Rab11 gene from Procambarus clarkii (PcRab11) and evaluated its potential involvement in immune response. The results showed PcRab11 was 1789 bp long, with an open reading frame of 645 bp encoding 211 amino acids and an estimated molecular weight of 23.8 kDa. Sequence analysis revealed its remarkable evolutionary conservation. The PcRab11 was widely expressed in various tissues, with highest levels in hepatopancreas, and localized within the cell cytoplasm. Upon infection with white spot syndrome virus (WSSV) or Aeromonas veronii, the expression of PcRab11 in immune organs was significantly induced. Furthermore, silencing PcRab11 reduced phagocytosis-related genes expression and haemocytes' phagocytic activity to FITC-labeled A. veronii, as well as decreased mortality and death time in WSSV or A. veronii infected P. clarkii. Additionally, the potential protein interaction between PcRab11 and 14-3-3ε was identified in haemocytes. Overall, our findings provided evidence for the involvement of Rab11 in P. clarkii's immune response, establishing a foundation to explore the immune role of core Rab proteins in crustaceans' innate immune system.

[Rate of Correct Inhaler Usage and Related Factors in Elderly Patients With Chronic Obstructive Pulmonary Disease].

BACKGROUND: Poor disease control in patients with chronic obstructive pulmonary disease (COPD) is associated with suboptimal inhaler use. PURPOSE: This study was designed to explore the accuracy of inhaler use and related factors in elderly patients with COPD. METHODS: A cross-sectional survey design was used to recruit patients with COPD from a medical centre in southern Taiwan who were over 65 years old and used inhalers regularly. All of the data as well as information on inhaler use accuracy were collected using a self-designed questionnaire and inhaler operation checklist. Multivariable logistic regression was used to analyse significant correlates of correct inhaler operation. RESULTS: The average age of the 150 participants was 75.0 years (SD = 7.5) years. Most used one type of inhaler only (86.0%). The rate of accurate inhaler operation was 40.7% (n = 61) for the sample, with dry powder inhalers associated with the highest accuracy (64%) and pressurized metered-dose inhalers associated with the lowest accuracy (1.6%). Multivariate logistic regression analysis showed that using a soft mist inhaler (adjusted odds ratio, AOR = 23.29; 95% confidence interval, 95% CI [2.84, 191.07]), using a dry powder inhaler (AOR =15.60, 95% CI [1.99, 122.26]), and higher satisfaction with the inhaler were positively and independently associated with accurate inhaler use (AOR = 1.94, 95% CI [1.09, 3.44]). CONCLUSIONS / IMPLICATIONS FOR PRACTICE: Important factors related to inhaler use accuracy include inhaler type and level of patient satisfaction with their inhaler. Healthcare professionals should regularly confirm that older patients are able to use their inhalers correctly and are satisfied with their inhalers.

Virtual reality-based simulation learning on geriatric oral health care for nursing students: a pilot study.

BACKGROUND: There is a great need for training and education in the nursing curriculum to improve nurses' knowledge and skills to provide oral health care. METHODS: A pilot study was conducted to evaluate the use of a virtual reality (VR)-based Oral Health Care Learning System to train geriatric oral health care among nursing students. Fifty undergraduate nursing students were randomly assigned to experimental (n = 25) and control (n = 25) groups. The experimental group received the VR-based simulation training on geriatric oral health care and the training was implemented twice at two weeks apart from March to November 2021. The control group did not receive the training intervention. Knowledge, attitude, and self-efficacy of geriatric oral health care as well as the intention to assist oral health care for older adults were assessed at the beginning, second, and fourth weeks. Generalized estimating equations were used to analyze the effectiveness of the VR-based simulation training. RESULTS: After the first round of training, students in the experimental group had significantly greater improvements in knowledge and self-efficacy of geriatric oral health care than in the control group. After the second round of training, students in the experimental group had significantly greater improvements in knowledge, attitude, and self-efficacy of geriatric oral health care as well as the intention to assist oral health care for older adult than in the control group. CONCLUSIONS: The VR-based simulation training was effective to improve undergraduate nursing students' knowledge, attitudes and self-efficacy of geriatric oral health as well as the intention to assist oral health care for older adults. The VR-based simulation learning system is an effective tool to provide practice experiences to build confidence and skills and to bridge the gap of understudied geriatric oral health content in entry-level nursing curricula. TRIAL REGISTRATION: ClinicalTrials.gov (NCT05248542; registration date 21/02/2022).

Higher-Order Topological In-Bulk Corner State in Pure Diffusion Systems.

Compared with conventional topological insulator that carries topological state at its boundaries, the higher-order topological insulator exhibits lower-dimensional gapless boundary states at its corners and hinges. Leveraging the form similarity between Schrödinger equation and diffusion equation, research on higher-order topological insulators has been extended from condensed matter physics to thermal diffusion. Unfortunately, all the corner states of thermal higher-order topological insulator reside within the band gap. Another kind of corner state, which is embedded in the bulk states, has not been realized in pure diffusion systems so far. Here, we construct higher-dimensional Su-Schrieffer-Heeger models based on sphere-rod structure to elucidate these corner states, which we term "in-bulk corner states." Because of the anti-Hermitian properties of diffusive Hamiltonian, we investigate the thermal behavior of these corner states through theoretical calculation, simulation, and experiment. Furthermore, we study the different thermal behaviors of in-bulk corner state and in-gap corner state. Our results would open a different gate for diffusive topological states and provide a distinct application for efficient heat dissipation.

The larva and adult of Helicoverpa armigera use differential gustatory receptors to sense sucrose.

Almost all herbivorous insects feed on plants and use sucrose as a feeding stimulant, but the molecular basis of their sucrose reception remains unclear. Helicoverpa armigera as a notorious crop pest worldwide mainly feeds on reproductive organs of many plant species in the larval stage, and its adult draws nectar. In this study, we determined that the sucrose sensory neurons located in the contact chemosensilla on larval maxillary galea were 100-1000 times more sensitive to sucrose than those on adult antennae, tarsi, and proboscis. Using the Xenopus expression system, we discovered that Gr10 highly expressed in the larval sensilla was specifically tuned to sucrose, while Gr6 highly expressed in the adult sensilla responded to fucose, sucrose and fructose. Moreover, using CRISPR/Cas9, we revealed that Gr10 was mainly used by larvae to detect lower sucrose, while Gr6 was primarily used by adults to detect higher sucrose and other saccharides, which results in differences in selectivity and sensitivity between larval and adult sugar sensory neurons. Our results demonstrate the sugar receptors in this moth are evolved to adapt toward the larval and adult foods with different types and amounts of sugar, and fill in a gap in sweet taste of animals.

Observation of parity-time symmetry in diffusive systems.

Phase modulation has scarcely been mentioned in diffusive physical systems because the diffusion process does not carry the momentum like waves. Recently, non-Hermitian physics provides a unique perspective for understanding diffusion and shows prospects in thermal phase regulation, exemplified by the discovery of anti-parity-time (APT) symmetry in diffusive systems. However, precise control of thermal phase remains elusive hitherto and can hardly be realized, due to the phase oscillations. Here we construct the PT-symmetric diffusive systems to achieve the complete suppression of thermal phase oscillation. The real coupling of diffusive fields is readily established through a strong convective background, and the decay-rate detuning is enabled by thermal metamaterial design. We observe the phase transition of PT symmetry breaking with the symmetry-determined amplitude and phase regulation of coupled temperature fields. Our work shows the existence of PT symmetry in dissipative energy exchanges and provides unique approaches for harnessing the mass transfer of particles, wave dynamics in strongly scattering systems, and thermal conduction.

Observation of non-Hermitian skin effect in thermal diffusion.

The paradigm shift of Hermitian systems into the non-Hermitian regime profoundly modifies inherent property of the topological systems, leading to various unprecedented effects such as the non-Hermitian skin effect (NHSE). In the past decade, the NHSE has been demonstrated in quantum, optical and acoustic systems. Beside those wave systems, the NHSE in diffusive systems has not yet been observed, despite recent abundant advances in the study of topological thermal diffusion. In this work, we design a thermal diffusion lattice based on a modified Su-Schrieffer-Heeger model and demonstrate the diffusive NHSE. In the proposed model, the asymmetric temperature field coupling inside each unit cell can be judiciously realized by appropriate configurations of structural parameters. We find that the temperature fields trend to concentrate toward the target boundary which is robust against initial excitation conditions. We thus experimentally demonstrated the NHSE in thermal diffusion and verified its robustness against various defects. Our work provides a platform for exploration of non-Hermitian physics in the diffusive systems, which has important applications in efficient heat collection, highly sensitive thermal sensing and others.

Trends and Changes in Intensive Care Use for Patients With Heart Failure in the Last Month of Life.

A good death is a human right. Unfortunately, patients with chronic heart failure (CHF) in the terminal stage still receive inappropriate life-sustaining treatment before death. There is limited understanding of the status of intensive care unit (ICU) admission, mechanical ventilation (MV), cardiopulmonary resuscitation (CPR), and even extracorporeal membrane oxygenation (ECMO) for patients with CHF before death, as well as their use of hospice-related services. This study investigated the trends and trend changes in intensive procedures and hospice-related services for patients with CHF in the last month of life. This population-based retrospective observational study included 25 375 patients with CHF from the National Health Insurance research database in Taiwan and collected information on their intensive treatments during the last month of life. We computed intensive treatment utilization rates and analyzed the trends and trend changes via joinpoint regression. The average percentage of patients with CHF admitted to ICUs was 53.27% (n = 13 516). A total of 327 (1.29%) patients with CHF received ECMO. The percentages of patients receiving MV (54.3%'41.5%) and CPR (41.5%'17%) decreased over time. Conversely, the percentage of ECMO use (0.52%'1.78%) increased. However, only 222 (0.87%) patients with CHF received hospice care in the last month of life between 2001 and 2013. The rates of ICU admission and life-sustaining treatment among patients with CHF in the month before death remain high, and hospice-related services remain inadequate. This study highlights the need for research and training in providing palliative and hospice care for patients with CHF.

Targeted inhibition of the HNF1A/SHH axis by triptolide overcomes paclitaxel resistance in non-small cell lung cancer.

Paclitaxel resistance is associated with a poor prognosis in non-small cell lung cancer (NSCLC) patients, and currently, there is no promising drug for paclitaxel resistance. In this study, we investigated the molecular mechanisms underlying the chemoresistance in human NSCLC-derived cell lines. We constructed paclitaxel-resistant NSCLC cell lines (A549/PR and H460/PR) by long-term exposure to paclitaxel. We found that triptolide, a diterpenoid epoxide isolated from the Chinese medicinal herb Tripterygium wilfordii Hook F, effectively enhanced the sensitivity of paclitaxel-resistant cells to paclitaxel by reducing ABCB1 expression in vivo and in vitro. Through high-throughput sequencing, we identified the SHH-initiated Hedgehog signaling pathway playing an important role in this process. We demonstrated that triptolide directly bound to HNF1A, one of the transcription factors of SHH, and inhibited HNF1A/SHH expression, ensuing in attenuation of Hedgehog signaling. In NSCLC tumor tissue microarrays and cancer network databases, we found a positive correlation between HNF1A and SHH expression. Our results illuminate a novel molecular mechanism through which triptolide targets and inhibits HNF1A, thereby impeding the activation of the Hedgehog signaling pathway and reducing the expression of ABCB1. This study suggests the potential clinical application of triptolide and provides promising prospects in targeting the HNF1A/SHH pathway as a therapeutic strategy for NSCLC patients with paclitaxel resistance. Schematic diagram showing that triptolide overcomes paclitaxel resistance by mediating inhibition of the HNF1A/SHH/ABCB1 axis.

Nonreciprocal Heat Circulation Metadevices.

Thermal nonreciprocity typically stems from nonlinearity or spatiotemporal variation of parameters. However, constrained by the inherent temperature-dependent properties and the law of mass conservation, previous works have been compelled to treat dynamic and steady-state cases separately. Here, by establishing a unified thermal scattering theory, the creation of a convection-based thermal metadevice which supports both dynamic and steady-state nonreciprocal heat circulation is reported. The nontrivial dependence between the nonreciprocal resonance peaks and the dynamic parameters is observed and the unique nonreciprocal mechanism of multiple scattering is revealed at steady state. This mechanism enables thermal nonreciprocity in the initially quasi-symmetric scattering matrix of the three-port metadevice and has been experimentally validated with a significant isolation ratio of heat fluxes. The findings establish a framework for thermal nonreciprocity that can be smoothly modulated for dynamic and steady-state heat signals, it may also offer insight into other heat-transfer-related problems or even other fields such as acoustics and mechanics.

Characteristics of CD4-1 gene and its immune responses against Aeromonas veronii infection by activating NF-κB signaling in Qihe crucian carp Carassius auratus.

CD4-1 found in bony fish contains four extracellular immunoglobulin (Ig)-like domains similar to that of mammalian CD4, which is crucial for the activation of CD4+ helper T-cell. However, there is limited knowledge regarding the molecular markers, immune functions and regulation mechanism of CD4-1 in teleosts due to their vast diversity. In this study, we cloned and characterized two isoforms of Qihe crucian carp CD4-1, designated as CaCD4-1.1 and CaCD4-1.2. We further explored their expression responses upon stimulation with Aeromonas veronii, and the regulation of their immune responses against A. veronii by NF-κB. The ORF of CaCD4-1.1 and CaCD4-1.2 cDNA encoded 477 and 466 amino acids, respectively. Both proteins contained seven conserved cysteine residues in the extracellular domain, and a CCC motif in their cytoplasm, respectively. However, CaCD4-1.1 exhibited a relatively limited similarity with CaCD4-1.2 in the ectodomain. The quantitative real-time polymerase chain reaction (qRT-PCR) analysis revealed that the mRNA expression of CaCD4-1.1 and CaCD4-1.2 exhibited differential constitutive expression across all examined tissues. Furthermore, the expression level of CD4-1.2 was higher than that of CD4-1.1 in the gills, head kidney, and spleen of Qihe crucian carp subjected to A. veronii challenge, while it was lower in the trunk kidney. Inhibition of NF-κB activity resulted in a decrease in the expression levels of CD4-1.1 and CD4-1.2 mRNA in the gill, while inducing an increase in expression levels in the spleen, in accordance with the observed ultrastructural changes in both organs. Interestingly, the impact of NF-κB on the mRNA expression level of CD4-1.1 appears to be stronger than that of CD4-1.2. Our results suggest that CaCD4-1.1 and CaCD4-1.2 could be expressed on T cells and antigen-sampling cells that exhibit similar characteristics to mammalian M cells, respectively, and differentially regulated by NF-κB in adaptive immune responses against bacterial infection. This research contributes to a better understanding of the crucial role of CD4-1 in the immune response of Qihe crucian carp and provide novel insights for the prevention and treatment of fish diseases in aquaculture.

Efficacy of a Smartphone App in Enhancing Medication Adherence and Accuracy in Individuals With Schizophrenia During the COVID-19 Pandemic: Randomized Controlled Trial.

BACKGROUND: Poor medication adherence or inaccuracy in taking prescribed medications plays an important role in the recurrence or worsening of psychiatric symptoms in patients with schizophrenia, and the COVID-19 pandemic impacted their medication adherence with exacerbated symptoms or relapse. The use of mobile health services increased during the COVID-19 pandemic, and their role in improving mental health is becoming clearer. OBJECTIVE: This study aimed to explore the effectiveness of a smartphone app (MedAdhere) on medication adherence and accuracy among patients with schizophrenia and to measure their psychiatric symptoms and cognitive functions. METHODS: In this 12-week experimental study, participants were provided interventions with the MedAdhere app, and data were collected between June 2021 and September 2022. A total of 105 participants were randomly assigned to either the experimental or control groups. We used the Positive and Negative Syndrome Scale and Mini-Mental State Examination to measure the participants' psychiatric symptoms and cognitive functions. Generalized estimating equations were used for data analysis. RESULTS: A total of 94 participants met the inclusion criteria and completed the protocol, and the medication adherence rate of the experimental group was 94.72% (2785/2940) during the intervention. Psychotic symptoms (positive, negative, and general psychopathology symptoms) and cognitive functions (memory, language, and executive function) were significantly improved in the experimental group compared to the control group after the intervention. CONCLUSIONS: The MedAdhere app effectively and significantly improved medication adherence and, thereby, the psychiatric symptoms of patients with schizophrenia. This artificial intelligence assisted app could be extended to all patients who need to be reminded to take medication on schedule. TRIAL REGISTRATION: ClinicalTrials.gov NCT05892120; https://clinicaltrials.gov/study/NCT05892120.

Role of HIF in fish inflammation.

The hypoxia-inducing factor (HIF) is a central transcription factor in cellular oxygen sensing and regulation. It is common that the inflammation always appears in many diseases, like infectious diseases in fishes, and the inflammation is often accompanied by hypoxia, as a hallmark of inflammation. Besides coordinating cellular responses to low oxygen, HIF-mediated hypoxia signaling pathway is also crucial for immune responses such as the regulations of innate immune cell phenotype and function, as well as metabolic reprogramming under the inflammation. However, the understanding of the molecular mechanisms by which HIFs regulate the inflammatory response in fish is still very limited. Here, we review the characteristics of HIF as well as its roles in innate immune cells and the infections caused by bacteria and viruses. The regulatory effects of HIF on the metabolic reprogramming of innate immune cells are also discussed and the future research directions are outlooked. This paper will serve as a reference for elucidating the molecular mechanism of HIF regulating inflammation and identifying treatment strategies to target HIF for fish disease.

Combining augmented and virtual reality simulation training to improve geriatric oral care performance in healthcare assistants: A randomized controlled trial.

Objective: Healthcare assistants (HCAs) are frontline caregivers for older adults. This study evaluated the effectiveness of combining augmented reality (AR) and virtual reality (VR) to implement oral healthcare simulation training for HCAs. Methods: An experimental design was adopted. HCAs were recruited and randomly assigned to an AR/VR group (n = 40) or a control group (n = 40). The AR/VR group received 2.5 h of AR/VR training. Participants were trained on the Bass brushing technique through AR and on scenario-based oral care procedures for various physical and oral health conditions in older adults through VR. A self-administered questionnaire was employed to collect data before and after the training. Generalized estimating equations were used to analyze the differences between pretest and posttest results. Results: After the training, the HCAs in the AR/VR group achieved a significantly greater increase in their level of oral care-related knowledge (ß = 2.55, effect size [ES] = 1.62), self-efficacy (ß = 4.23, ES = 0.75), and behavioral intention (ß = 2.10, ES = 0.55) relative to the control group. Conclusion: This study revealed that the application of an AR/VR simulation system can effectively improve the geriatric oral care performance of HCAs.

The role of CcPTGS2a in immune response against Aeromonas hydrophila infection in common carp (Cyprinus carpio).

Prostaglandin-endoperoxide synthase 2 (PTGS2), a crucial enzyme in prostaglandin synthesis, catalyzes the conversion of arachidonic acid to prostaglandins and plays a significant role in the inflammatory response. This investigation aimed to determine the regulatory role of PTGS2a in the innate immune response to bacterial infection in fish. To achieve this objective, the CcPTGS2a gene was identified and characterized in common carp (Cyprinus carpio), and its function in immune defense was investigated. According to the sequence and structural analysis results, CcPTGS2a had an open reading frame of 1806 bp that encoded 602 amino acids. It was estimated that the protein's theoretical molecular weight was 69.0 kDa, and its isoelectric point was 8.10. The structure of CcPTGS2a was observed to be conserved, with an epidermal growth factor domain and a peroxidase domain present. Moreover, the amino acid sequence of CcPTGS2a exhibited significant homology with the amino acid sequences of several fish species. CcPTGS2a mRNA was detected in the healthy tissues of common carp, with higher expression in the head kidney, spleen, gills, and liver. Following the challenges with Aeromonas hydrophila and lipopolysaccharide, CcPTGS2a mRNA showed unique geographic and temporal expression patterns, with significant increases detected in the head kidney, gills, spleen, and liver. Additionally, the recombinant CcPTGS2a protein exhibited detectable bacterial binding to various bacteria. As determined by subcellular localization analysis, CcPTGS2a was predominantly localized in the nucleus and cytoplasm. Furthermore, it was discovered that the overexpression of CcPTGS2a stimulated the up-regulation of ferroptosis-related genes and inflammatory cytokine mRNA expression in fish and EPC (Epithelioma papulosum cyprinid) cells while concurrently reducing the bacterial load of A. hydrophila. In contrast, the interference of CcPTGS2a decreased the mRNA expression of ferroptosis-related genes and inflammatory cytokines in fish and EPC cells and increased the bacterial load of A. hydrophila. Notably, A. hydrophila stimulation resulted in the up-regulation of CcPTGS2a protein expression in EPC cells. These results suggested that CcPTGS2a was involved in the immune response to bacterial infections in common carp.

Two CcCCL19bs orchestrate an antibacterial immune response in Yellow River carp (Cyprinus carpio haematopterus).

Chemokines are a group of chemotactic cytokines with an essential role in homeostasis as well as immunity via specific G protein-coupled receptors and atypical receptors. In our study, two Yellow River carp (Cyprinus carpio haematopterus) CCL19b genes (CcCCL19bs), tentatively named CcCCL19b_a and CcCCL19b_b, were cloned. The open reading frames (ORFs) of CcCCL19b_a and CcCCL19b_b were both 333 bp that encoded a 12 kDa protein with 110 amino acid residues. CcCCL19bs contained a signal peptide and a SCY domain with four typical conserved cysteine residues. The two CcCCL19b proteins shared high similarities with each other in both secondary and three-dimensional structure. Phylogenetic analysis showed that CcCCL19bs and other CCL19bs from tetraploid cyprinid fish were clustered into one clade. CcCCL19bs were highly expressed in gill and intestine in healthy fish, and a significant up-regulation of gene expression after Aeromonas hydrophila infection and poly(I:C) stimulation was observed in gill, liver, and head kidney. Furthermore, chemotaxis and antibacterial activity of CcCCL19bs were studied. The results indicated that recombinant CcCCL19b_a and CcCCL19b_b protein (rCcCCL19b_a and rCcCCL19b_b) exhibited significant attraction to primary head kidney leukocytes (HKLs). Meanwhile, both of rCcCCL19bs could promote the proliferation of HKLs, and significantly up-regulate the expressions of IL-1ß, CCR7, and IL-6, and down-regulate the expression of IL-10 in primary HKLs. In vitro, rCcCCL19bs could bind and aggregate A. hydrophila and Staphylococcus aureus. The rCcCCL19bs exhibited significant antibacterial activity against A. hydrophila, but not S. aureus. Moreover, they inhibited the growth of A. hydrophila and S. aureus. In vivo, overexpression of CcCCL19bs contributed to the bacterial clearance. These studies suggested that CcCCL19bs orchestrate an antibacterial immune response.

Activation Mechanism of CcGSDMEb-1/2 and Regulation for Bacterial Clearance in Common Carp (Cyprinus carpio).

Gasdermin E (GSDME), to date, is considered the only direct executor of the pyroptosis process in teleost and plays an important role in innate immunity. In common carp (Cyprinus carpio), there contains two pairs of GSDME (GSDMEa/a-like and GSDMEb-1/2), and the pyroptotic function and regulation mechanism of GSDME still remain unclear. In this study, we identified two GSDMEb genes of common carp (CcGSDMEb-1/2), which contain a conserved N-terminal pore-forming domain, C-terminal autoinhibitory domain, and a flexible and pliable hinge region. We investigated the function and mechanism of CcGSDMEb-1/2 in association with inflammatory and apoptotic caspases in Epithelioma papulosum cyprinid cells and discovered that only CcCaspase-1b could cleave CcGSDMEb-1/2 through recognizing the sites 244FEVD247 and 244FEAD247 in the linker region, respectively. CcGSDMEb-1/2 exerted toxicity to human embryonic kidney 293T cells and bactericidal activity through its N-terminal domain. Interestingly, after i.p. infection by Aeromonas hydrophila, we found that CcGSDMEb-1/2 were upregulated in immune organs (head kidney and spleen) at the early stage of infection, but downregulated in mucosal immune tissues (gill and skin). After CcGSDMEb-1/2 were knocked down and overexpressed in vivo and in vitro, respectively, we found that CcGSDMEb-1/2 could govern the secretion of CcIL-1ß and regulate the bacterial clearance after A. hydrophila challenge. Taken together, in this study, it was demonstrated that the cleavage mode of CcGSDMEb-1/2 in common carp was obviously different from that in other species and played an important role in CcIL-1ß secretion and bacterial clearance.