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Scavenger receptors (SRs), a category of pattern recognition receptors primarily expressed on the surface of myeloid cells, play pivotal roles in oxidation response and lipid metabolism. However, current research on Scavenger Receptor class F type II (SRECⅡ) revolves around Van Den Ende-Gupta Syndrome (VDEG), the potential function of SRECII, particularly in regulating lipid metabolism and oxidative stress processes, remains elusive. Herein, we elucidate that SRECII from Epinephelus coioides (EcSRECII) may modulate fatty acid oxidation and oxidative stress levels via interactions with lipoprotein particles. EcSRECII mediates the internalization of oxidized Low-Density Lipoprotein (oxLDL), thereby inducing lipid accumulation. This process upregulates the expression of genes associated with lipid synthesis and concurrently suppresses those involved in lipolysis. Additionally, EcSRECII exacerbates the production of Reactive Oxygen Species (ROS) following oxLDL exposure, evidenced by significantly heightened activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), increased accumulation of malondialdehyde (MDA), and enhanced total antioxidant capacity (T-AOC). Furthermore, we reveal that EcSRECII-mediated oxLDL internalization culminates in apoptosis and necrosis in GS cells. Ultimately, we demonstrate that EcSRECII augments oxLDL-induced cellular oxidative stress and inflammatory responses, effects that are notably mitigated by EcSRECII knockdown or pretreatment with the fatty acid synthase (FAS) inhibitor C75. Collectively, our study underscores the role of EcSRECII in facilitating oxLDL internalization and subsequent lipid metabolism remodeling, thereby participating in the intricate regulation of intracellular oxidative stress and immune responses., (Copyright © 2024. Published by Elsevier Inc.)

Vibrio parahaemolyticus , as one of the main pathogens of marine vibriosis, has brought huge losses to aquaculture. However, the interaction mechanism between V. parahaemolyticus and Epinephelus coioides remains unclear. Moreover, there is a lack of comprehensive multi-omics analysis of the immune response of grouper spleen to V. parahaemolyticus . Herein, E. coioides was artificially injected with V. parahaemolyticus , and it was found that the mortality was 16.7% in the early stage of infection, and accompanied by obvious histopathological lesions in the spleen. Furthermore, 1586 differentially expressed genes were screened by mRNA-seq. KEGG analysis showed that genes were significantly enriched in immune-related pathways, Acute-phase immune response, Apoptosis, Complement system and Cytokine-cytokine receptor interaction. As for miRNA-seq analysis, a total of 55 significantly different miRNAs were identified. Further functional annotation analysis indicated that the target genes of differentially expressed miRNAs were enriched in three important pathways (Phosphatidylinositol signaling system, Lysosome and Focal adhesions). Through mRNA-miRNA integrated analysis, 1427 significant miRNA-mRNA pairs were obtained and " p53 signaling pathway", "Intestinal immune network for IgA production" were considered as two crucial pathways. Finally, miR-144-y , miR-497-x , novel-m0459-5p , miR-7133-y , miR-378-y , novel-m0440-5p and novel-m0084-3p may be as key miRNAs to regulate immune signaling pathways via the miRNA-mRNA interaction network. The above results suggest that the mRNA-miRNA integrated analysis not only sheds new light on the molecular mechanisms underlying the interaction between host and V. parahaemolyticus but also provides valuable and new insights into resistance to vibrio infection., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Qiao, Lu, Xu, Deng, Lai, Wu, Lin, Zhang and Lu.)

Coronavirus disease 2019 (COVID-19) raises the issue of how hypoxia destroys normal physiological function and host immunity against pathogens. However, there are few or no comprehensive omics studies on this effect. From an evolutionary perspective, animals living in complex and changeable marine environments might develop signaling pathways to address bacterial threats under hypoxia. In this study, the ancient genomic model animal Takifugu obscurus and widespread Vibrio parahaemolyticus were utilized to study the effect. T . obscurus was challenged by V . parahaemolyticus or (and) exposed to hypoxia. The effects of hypoxia and infection were identified, and a theoretical model of the host critical signaling pathway in response to hypoxia and infection was defined by methods of comparative metabolomics and proteomics on the entire liver. The changing trends of some differential metabolites and proteins under hypoxia, infection or double stressors were consistent. The model includes transforming growth factor-β1 (TGF-β1), hypoxia-inducible factor-1α (HIF-1α), and epidermal growth factor (EGF) signaling pathways, and the consistent changing trends indicated that the host liver tended toward cell proliferation. Hypoxia and infection caused tissue damage and fibrosis in the portal area of the liver, which may be related to TGF-β1 signal transduction. We propose that LRG (leucine-rich alpha-2-glycoprotein) is widely involved in the transition of the TGF-β1/Smad signaling pathway in response to hypoxia and pathogenic infection in vertebrates as a conserved molecule., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Xu, Yu, Ye, Gao, Deng, Lu, Lin, Zhang and Lu.)