Activation of TLR2 heterodimers-mediated NF-κB, MAPK, AKT signaling pathways is responsible for Vibrio alginolyticus triggered inflammatory response in vitro

Fatty acid synthase (FASN) inhibits the cervical squamous cell carcinoma (CESC) progression through the Akt/mTOR signaling pathway

BACKGROUND

Cervical cancer is a malignant tumor that affects females and remains the cause of the highest morbidity and mortality among women worldwide. Currently, gene-targeted therapy is a novel treatment option for clinicians. Furthermore, fatty acid synthase (FASN) plays a therapeutic role in various cancers. Nonetheless, the mechanism of action of this enzyme in cervical squamous cell carcinoma and cervical duct adenocarcinoma (CESC) has not yet been reported.

METHODS

RNA (ribonucleic acid) sequencing data and clinical information were obtained from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx). The expression levels of FASN were obtained from Gene Expression Profiling Interactive Analysis 2 (GEPIA2) and Human Protein Atlas (HPA). Univariate and multivariate Cox regression analyses were utilized to assess independent prognostic factors associated with survival. A nomogram and receiver operating characteristic curve (ROC) were employed to evaluate survival and predictive power. In vitro experiments and real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) were conducted to identify cell interference efficiency. MTS, monoclonal formation, and EDU assays were used to determine cell viability. Wound healing and invasion assays (transwell assay) were used to evaluate cell migration and invasion. Finally, Hoechst 33342, propidium iodide (PI) staining and Annexin V-FITC staining were used to assess apoptosis and the cell cycle, while western blotting was utilized to determine the protein expression levels.

RESULTS

FASN was aberrantly expressed in various cancers, including CESC, where it was highly expressed. Kaplan-Meier, univariate, multivariate Cox regression analyses and ROC curve indicated that FASN is a potential key indicator of survival prognosis among CESC patients and demonstrated good predictive ability and efficacy. Complementary in vitro experiments confirmed that FASN is an important target for CESC therapy.

CONCLUSION

The current study validated the biological and clinical significance of FASN in CESC prognosis, suggesting that FASN knockdown may exert antitumor activity against cervical cancer through the Akt/mTOR signaling pathway.

IL-1β/NF-κB signaling inhibits IGF-1 production via let-7f-5p in dendritic epidermal T cells

Dendritic epidermal T cells (DETCs) are the main source of insulin-like growth factor-1 (IGF-1) in epidermal tissue, which promote re-epithelialization and wound healing. In refractory wounds, IL-1β has been shown to activate NF-κB and suppress IGF-1 expression in DETCs. Nevertheless, the underlying mechanisms remain unclear. In this study, chromatin immunoprecipitation analysis revealed that IL-1β did not inhibit NF-κB binding to IGF-1 promoter, indicating that IL-1β/NF-κB may suppress IGF-1 expression by alternative mechanisms. MiRNAs negatively regulate gene expression predominantly by base pairing to the 3' untranslation region (UTR) of target mRNAs. Let-7f-5p, miR-1a-3p, and miR-98-5p have been identified as IGF-1-specific miRNAs that can bind directly to the 3'UTR of IGF-1 mRNA and dysregulate IGF-1 mRNA and protein levels. In IL-1β-treated epidermis around wounds or DETCs in vitro, NF-κB promoted the expression of let-7f-5p, and IGF-1 expression was impeded via NF-κB/let-7f-5p pathway. As pre-let-7f-5p, let-7f-1 is located in the 3'UTR of LOC118568094, and let-7f-2 is located in the intron of HUWE1. We discovered that NF-κB p65 bound to the promoters of LOC118568094 and HUWE1 to accelerate let-7f-5p expression, but NF-κB p65 did not affect the methylation levels of LOC118568094 and HUWE1 CpG islands. Injections of Let-7f-5p antagomir into IL-1β-treated and ischemic wound margins restored IGF-1 secretion in DETCs and promoted wound healing. In conclusion, we demonstrated that NF-κB signaling pathway activated by IL-1β could increase let-7f-5p expression to inhibit IGF-1 production in DETCs and delay wound healing. And let-7f-5p antagomir utilized in wound margin could effectively promote refractory wound healing.

ROS Induced by Streptococcus agalactiae Activate Inflammatory Responses via the TNF-α/NF-κB Signaling Pathway in Golden Pompano Trachinotus ovatus (Linnaeus, 1758)

Streptococcus agalactiae is common pathogenic bacteria in aquaculture and can cause mass mortality after fish infection. This study aimed to investigate the effects of S. agalactiae infection on the immune and antioxidant regulatory mechanisms of golden pompano (Trachinotus ovatus). Serum and liver samples were obtained at 0, 6, 12, 24, 48, 96, and 120 h after golden pompano infection with S. agalactiae for enzyme activity and gene expression analyses. After infection with S. agalactiae, the content of reactive oxygen species (ROS) in serum was significantly increased (p < 0.05). Serum levels of glucose (GLU), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and malondialdehyde (MDA) increased and then decreased (p < 0.05), reaching a maximum at 6 h. Serum antioxidant enzyme (LZM) activity increased significantly (p < 0.05) and reached a maximum at 120 h. In addition, the mRNA expression levels of antioxidant genes (SOD, CAT, and GPx) in the liver increased and then decreased, reaching the maximum at 24 h, 48 h, and 24 h, respectively. During the experimental period, the mRNA expression levels of NF-κB-related genes of the inflammatory signaling pathway inhibitory κB (IκB) showed an overall decreasing trend (p < 0.05) and the lowest expression at 120 h, whereas the mRNA expression levels of tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), IκB kinase (IKK), and nuclear factor NF-κB increased significantly (p < 0.05) and the highest expression was at 120 h. In conclusion, these results showed that S. agalactiae could activate internal regulatory signaling in the liver of golden pompano to induce defense and immune responses. This study is expected to lay a foundation to develop the healthy aquaculture of golden pompano and promote a more comprehensive understanding of its disease resistance mechanisms.

Andrographolide promote the growth and immunity of Litopenaeus vannamei, and protects shrimps against Vibrio alginolyticus by regulating inflammation and apoptosis via a ROS-JNK dependent pathway

Vibrio alginolyticus (V. alginolyticus) is one of the major pathogens causing mass mortality of shrimps worldwide, affecting energy metabolism, immune response and development of shrimps. In the context of the prohibition of antibiotics, it is necessary to develop a drug that can protect shrimp from V. alginolyticus. Andrographolide (hereinafter called Andr), a traditional drug used in Chinese medicine, which possesses diverse biological effects including anti-bacteria, antioxidant, immune regulation. In this study, we investigated the effect of Andr on growth, immunity, and resistance to V. alginolyticus infection of Litopenaeus vannamei (L. vannamei) and elucidate the underlying molecular mechanisms. Four diets were formulated by adding Andr at the dosage of 0 g/kg (Control), 0.5 g/kg, 1 g/kg, and 2 g/kg in the basal diet, respectively. Each diet was randomly fed to one group with three replicates of shrimps in a 4-week feeding trial. The results showed that dietary Andr improved the growth performance and non-specific immune function of shrimps. L. vannamei fed with Andr diets showed lower mortality after being challenged by V. alginolyticus. After 6 h of V. alginolyticus infection, reactive oxygen species (ROS) production, tissue injury, apoptosis, expression of inflammatory factors (IL-1 β and TNFα) and apoptosis-related genes (Bax, caspase3 and p53) were increased in hemocytes and hepatopancreas, while feeding diet with 0.5 g/kg Andr could inhibit the increase. Considering that JNK are important mediators of apoptosis, we examined the influence of Andr on JNK activity during V. alginolyticus infection. We found that Andr inhibited JNK activation induced by V. alginolyticus infection on L. vannamei. The ROS scavenger N-acetyl-l-cysteine (NAC) suppressed V. alginolyticus-induced inflammation and apoptosis, suggesting that ROS play an important role in V. alginolyticus-induced inflammation and apoptosis. Treated cells with JNK specific activator anisomycin, the inflammation and apoptosis inhibited by Andr were counteracted. Collectively, Andr promote the growth and immunity of L. vannamei, and protects shrimps against V. alginolyticus by regulating inflammation and apoptosis via a ROS-JNK dependent pathway. These results improve the understanding of the pathogenesis of V. alginolyticus infection and provide clues to the development of effective drugs against V. alginolyticus.

Rhodococcus equi-Derived Extracellular Vesicles Promoting Inflammatory Response in Macrophage through TLR2-NF-κB/MAPK Pathways

Rhodococcus equi (R. equi) is a Gram-positive coccobacillus that causes pneumonia in foals of less than 3 months, which have the ability of replication in macrophages. The ability of R. equi persist in macrophages is dependent on the virulence plasmid pVAPA. Gram-positive extracellular vesicles (EVs) carry a variety of virulence factors and play an important role in pathogenic infection. There are few studies on R. equi-derived EVs (R. equi-EVs), and little knowledge regarding the mechanisms of how R. equi-EVs communicate with the host cell. In this study, we examine the properties of EVs produced by the virulence strain R. equi 103+ (103+-EVs) and avirulenct strain R. equi 103− (103−-EVs). We observed that 103+-EVs and 103−-EVs are similar to other Gram-positive extracellular vesicles, which range from 40 to 260 nm in diameter. The 103+-EVs or 103−-EVs could be taken up by mouse macrophage J774A.1 and cause macrophage cytotoxicity. Incubation of 103+-EVs or 103−-EVs with J774A.1 cells would result in increased expression levels of IL-1β, IL-6, and TNF-α. Moreover, the expression of TLR2, p-NF-κB, p-p38, and p-ERK were significantly increased in J774A.1 cells stimulated with R. equi-EVs. In addition, we presented that the level of inflammatory factors and expression of TLR2, p-NF-κB, p-p38, and p-ERK in J774A.1 cells showed a significant decreased when incubation with proteinase K pretreated-R. equi-EVs. Overall, our data indicate that R. equi-derived EVs are capable of mediating inflammatory responses in macrophages via TLR2-NF-κB/MAPK pathways, and R. equi-EVs proteins were responsible for TLR2-NF-κB/MAPK mediated inflammatory responses in macrophage. Our study is the first to reveal potential roles for R. equi-EVs in immune response in R. equi-host interactions and to compare the differences in macrophage inflammatory responses mediated by EVs derived from virulent strain R. equi and avirulent strain R. equi. The results of this study have improved our knowledge of the pathogenicity of R. equi.