Lost and Found: The Family of NF-κB Inhibitors Is Larger than Assumed in Salmonid Fish

ToIκB and ToIKK genes from golden pompano (Trachinotus ovatus): Molecular characterization, expression, and association with tolerance to Streptococcus agalactiae infection

Effective disease management is crucial for sustainable aquaculture, particularly for economically important species like golden pompano (Trachinotus ovatus). Streptococcus agalactiae represents a major threat to this species, leading to severe health issues and significant economic losses. Understanding the immune mechanisms involved is essential to address this challenge. The IκB and IKK genes are known to be key regulators of immune responses, playing pivotal roles in modulating inflammatory pathways during infections. However, their specific roles in golden pompano immunity are not well characterized. In this study, we used bioinformatics analysis and tissue-specific expression profiling to investigate the roles of IκB and IKK genes in golden pompano during bacterial infection. The results demonstrated that ToIKK was significantly upregulated during the early stages of infection, indicating rapid immune activation, while ToIκB showed an initial decrease followed by recovery, suggesting its involvement in inflammation modulation. These genes were found to regulate the NF-κB signaling pathway, which is crucial for coordinating the immune response to bacterial infection. This research provides valuable insights into the molecular basis of golden pompano immune response against S. agalactiae, offering a foundation for developing targeted anti-infection strategies and improving disease resistance and health management practices in aquaculture.

Dietary Chlorella vulgaris supplementation modulates health, microbiota and the response to oxidative stress of Atlantic salmon

Microalgae are emerging as functional feed ingredients in aquaculture due to their immune-stimulating and stress-modulating properties. We investigated the potential of the microalgae Chlorella vulgaris as a feed supplement to improve the health and modulate microbiota and stress responses of Atlantic salmon. Triplicate groups of Atlantic salmon (~ 126 g) were reared in a recirculating aquaculture system (RAS) at 15 °C and received diets supplemented with 2% (CV2) or 14% (CV14) spray-dried C. vulgaris daily, 14% once weekly (CV14w), or a control diet (CD) for 8 weeks. Subsequently, all groups were exposed to an acute one-hour peracetic acid (CH3CO3H; PAA) treatment, a commonly used disinfectant in RAS. While CV14 increased feed conversion (FCR) significantly, feeding the diets CV2 and CV14w improved protein retention efficiency. CV14 significantly modulated beta-diversity in the intestinal digesta and mucosa, but this effect was already visible in fish fed CV2. Feeding CV14 and, to a lesser degree, CV2 increased the relative abundances of Paenarthrobacter and Trichococcus in the digesta and mucosa, which are able to metabolize complex carbohydrates. However, the same diets reduced the abundance of the lactic acid bacteria Lactobacillus and Weissella in the digesta and Floricoccus in the mucosa. Peracetic acid exposure induced systemic stress (increase in plasma glucose and cortisol) and a local immune response in the gill, with the most prominent upregulation of several immune- and stress-regulated genes (clra, cebpb, marco, tnfrsf14, ikba, c1ql2, drtp1) 18 h after exposure in fish fed the control diet. Fish receiving CV14 once a week showed a reduced transcriptional response to PAA exposure. Catalase protein abundance in the liver increased following exposure to PAA, while superoxide dismutase abundance in the gill and liver was increased in response to C. vulgaris inclusion before stress. Overall, the results highlight that a high (14%) inclusion rate of C. vulgaris in feed for Atlantic salmon impairs feed conversion and shifts the intestinal microbiota composition in digesta and mucosa. Weekly feeding of C. vulgaris proves a viable approach in improving protein retention and improving transcriptional resilience towards oxidative stress in increasingly intensive production systems. Thereby this study may motivate future studies on optimizing temporal feeding schedules for health-promoting aquafeeds.

Genome-wide CRISPR screening identifies the pivotal role of ANKRD42 in colorectal cancer metastasis through EMT regulation

Colorectal cancer (CRC), a pervasive and lethal malignancy of gastrointestinal cancer, imposes significant challenges due to the occurrence of distant metastasis in advanced stages. Understanding the intricate regulatory mechanisms driving CRC distant metastasis is of paramount importance. CRISPR-Cas9 screening has emerged as a powerful tool for investigating tumor initiation and progression. However, its application in studying CRC distant metastasis remains largely unexplored. To establish a model that faithfully recapitulates CRC liver metastasis in patients, we developed an in vivo genome-wide CRISPR-Cas9 screening approach using a spleen-injected liver metastasis mouse model. Through comprehensive screening of a whole-genome sgRNA library, we identified ANKRD42 as a pivotal regulatory gene facilitating CRC liver metastasis. Analysis of the TCGA database and our clinical cohorts unveiled heightened ANKRD42 expression in metastases. At the cellular level, the attenuation of ANKRD42 impaired the migration and invasion processes of tumor cells. In vivo experiments further validated these observations, highlighting the diminished liver metastatic capacity of tumor cells upon ANKRD42 knockdown. To unravel the specific mechanisms by which ANKRD42 regulates CRC distant metastasis, we leveraged patient-derived organoid (PDO) models. Depleting ANKRD42 in PDOs sourced from liver metastases precipitated the downregulation of pivotal genes linked to epithelial-mesenchymal transition (EMT), including CDH2 and SNAI2, thereby effectively suppressing tumor metastasis. This study not only establishes a conceptual framework but also identifies potential therapeutic avenues for advanced-stage distant metastasis in CRC patients.

Therapeutic potential of Lingjiao Gouteng decoction in acute alcohol intoxication and alcohol-induced brain injury involving the RhoA/ROCK2/NF-κB signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Alcohol misuse persists as a prevalent societal concern and precipitates diverse deleterious consequences, entailing significant associated health hazards including acute alcohol intoxication (AAI). Binge drinking, a commonplace pattern of alcohol consumption, may incite neurodegeneration and neuronal dysfunction. Clinicians tasked with managing AAI confront a dearth of pharmaceutical intervention alternatives. In contrast, natural products have garnered interest due to their compatibility with the human body and fewer side effects. Lingjiao Gouteng decoction (LGD), a classical traditional Chinese medicine decoction, represents a frequently employed prescription in cases of encephalopathy, although its efficacy in addressing acute alcoholism and alcohol-induced brain injury remains inadequately investigated.

AIM OF THE STUDY

To investigate the conceivable therapeutic benefits of LGD in AAI and alcohol-induced brain injury, while delving into the underlying fundamental mechanisms involved.

MATERIALS AND METHODS

We established an AAI mouse model through alcohol gavage, and LGD was administered to the mice twice at the 2 h preceding and 30 min subsequent to alcohol exposure. The study encompassed the utilization of the loss of righting reflex assay, histopathological analysis, enzyme-linked immunosorbent assays, and cerebral tissue biochemical assays to investigate the impact of LGD on AAI and alcohol-induced brain injury. These assessments included a comprehensive evaluation of various biomarkers associated with the inflammatory response and oxidative stress. Finally, RT-qPCR, Western blot, and immunofluorescence staining were carried out to explore the underlying mechanisms through which LGD exerts its therapeutic influence, potentially through the regulation of the RhoA/ROCK2/NF-κB signaling pathway.

RESULTS

Our investigation underscores the therapeutic efficacy of LGD in ameliorating AAI, as evidenced by discernible alterations in the loss of righting reflex assay, pathological analysis, and assessment of inflammatory and oxidative stress biomarkers. Furthermore, the results of RT-qPCR, Western blot, and immunofluorescence staining manifest a noteworthy regulatory effect of LGD on the RhoA/ROCK2/NF-κB signaling pathway.

CONCLUSIONS

The present study confirmed the therapeutic potential of LGD in AAI and alcohol-induced brain injury, and the protective effects of LGD against alcohol-induced brain injury may be intricately linked to the RhoA/ROCK2/NF-κB signaling pathway.

The Roles of RhoA/ROCK/NF-κB Pathway in Microglia Polarization Following Ischemic Stroke

Ischemic stroke is the leading cause of death and disability worldwide. Nevertheless, there still lacks the effective therapies for ischemic stroke. Microglia are resident macrophages of the central nervous system (CNS) and can initiate immune responses and monitor the microenvironment. Microglia are activated and polarize into proinflammatory or anti‑inflammatory phenotype in response to various brain injuries, including ischemic stroke. Proinflammatory microglia could generate immunomodulatory mediators, containing cytokines and chemokines, these mediators are closely associated with secondary brain damage following ischemic stroke. On the contrary, anti-inflammatory microglia facilitate recovery following stroke. Regulating the activation and the function of microglia is crucial in exploring the novel treatments for ischemic stroke patients. Accumulating studies have revealed that RhoA/ROCK pathway and NF-κB are famous modulators in the process of microglia activation and polarization. Inhibiting these key modulators can promote the polarization of microglia to anti-inflammatory phenotype. In this review, we aimed to provide a comprehensive overview on the role of RhoA/ROCK pathway and NF-κB in the microglia activation and polarization, reveal the relationship between RhoA/ROCK pathway and NF-κB in the pathological process of ischemic stroke. In addition, we likewise discussed the drug modulators targeting microglia polarization.

The role of RhoA/ROCK pathway in the ischemic stroke-induced neuroinflammation

It is widely known that ischemic stroke is the prominent cause of death and disability. To date, neuroinflammation following ischemic stroke represents a complex event, which is an essential process and affects the prognosis of both experimental stroke animals and stroke patients. Intense neuroinflammation occurring during the acute phase of stroke contributes to neuronal injury, BBB breakdown, and worse neurological outcomes. Inhibition of neuroinflammation may be a promising target in the development of new therapeutic strategies. RhoA is a small GTPase protein that activates a downstream effector, ROCK. The up-regulation of RhoA/ROCK pathway possesses important roles in promoting the neuroinflammation and mediating brain injury. In addition, nuclear factor-kappa B (NF-κB) is another vital regulator of ischemic stroke-induced neuroinflammation through regulating the functions of microglial cells and astrocytes. After stroke onset, the microglial cells and astrocytes are activated and undergo the morphological and functional changes, thereby deeply participate in a complicated neuroinflammation cascade. In this review, we focused on the relationship among RhoA/ROCK pathway, NF-κB and glial cells in the neuroinflammation following ischemic stroke to reveal new strategies for preventing the intense neuroinflammation.