The rising incidence of hypercholesterolemia has established probiotic intervention as a safe and effective preventive and mitigative strategy. Paocai is a traditional fermented food abundant in natural probiotics, many of which have yet to be explored and functionally characterized. In this study, Lactiplantibacillus plantarum NMG11, which has high in vitro degradation of cholesterol (53.13

Obesity-related chronic inflammation in adipose tissue is closely associated with macrophage infiltration and M1 polarization. Adipose tissue macrophages (ATMs) aggravate metabolic disorders and inflammation in adipocytes. However, the molecular mechanisms underlying this process in fish remain unclear. In this study, we established an in vitro co-culture system comprising M1 macrophages and adipocytes derived from large yellow croaker (Larimichthys crocea). The results demonstrated that M1 macrophages significantly upregulated the mRNA expression of pro-inflammatory genes in co-cultured adipocytes, while downregulating the anti-inflammatory gene expression. M1 macrophages significantly increased the phosphorylation levels of p38 and JNK MAPK signaling pathway. Inhibition of p38 and JNK significantly attenuated the M1-induced upregulation of pro-inflammatory genes in co-cultured adipocytes. Moreover, M1 macrophages significantly reduced insulin signaling-related genes expression and AKT phosphorylation level, suggesting impaired insulin signaling. Inhibition of AKT further aggravated the M1-induced inflammatory response in co-cultured adipocytes. Furthermore, M1 macrophages significantly downregulated the expression of peroxisome proliferator-activated receptor γ (PPARγ) in co-cultured adipocytes. Activation of PPARγ with troglitazone significantly alleviated the M1-induced inflammation in co-cultured adipocytes, whereas its inhibition with GW9662 exacerbated the inflammatory response. The M1-induced changes in PPARγ expression were significantly modulated by inhibition of p38, JNK or AKT, indicating that PPARγ acts a downstream of MAPK and AKT pathways. Notably, PPARγ directly bound to the promoters of TNF-α and IL-1β, thereby suppressing their transcription. Collectively, these findings demonstrated that M1 macrophages induced inflammatory responses in co-cultured adipocytes via the MAPK/AKT-PPARγ signaling axis. This study provides novel insights into the molecular regulation of adipose tissue inflammation in fish and may offer potential targets for addressing obesity-related metabolic disorders from an evolutionary perspective.

Hyperuricemia represents a systemic disorder manifested as purine metabolism dysregulation and multi-organ dysfunction, often underpinned by a disrupted host-microbe interface, which calls for multi-targeted and tolerable therapeutic strategies. This study developed a lactic acid bacteria (LAB) consortium comprising Lactiplantibacillus plantarum SC32, Pediococcus acidilactici FB13, and Lactiplantibacillus plantarum PL49, screened from traditional fermented foods and infant feces for their respective bioactivities in nucleotide degradation, xanthine oxidase (XOD) inhibition, and uric acid (UA) disposal. In hyperuricemic mice, this LAB consortium significantly reduced serum UA and urea nitrogen levels. It achieved multi-organ protection by mitigating hepatic and renal inflammation and fibrosis, alongside restoring intestinal barrier integrity. Further analysis indicated that the LAB consortium was associated with reduced UA synthesis, as reflected by inhibited XOD activity and downregulated XOD/PNP expression, and with altered UA transporter expression (SLC22A6, ABCG2, SLC2A9) favoring UA elimination. LAB consortium intervention induced favorable gut microbial shifts, characterized by enrichment of purine-catabolizing and SCFA-producing taxa and reduction of pro-inflammatory groups, and concurrently normalized purine and pyrimidine metabolism. Spearman correlation analysis identified associations between specific gut microbial taxa and both host biochemical parameters and key purine/pyrimidine metabolites. Collectively, this study provides preliminary evidence supporting the LAB consortium as a food-grade candidate for the amelioration of hyperuricemia, mitigation of multi-organ dysfunction, and preservation of microbiomemetabolome homeostasis.

A limited supply and price shortages of fishmeal with the expansion of aquaculture make it necessary to seek alternative protein sources. Soybean meal (SM) has been the widely preferred replacer for fishmeal in fish diets. Nevertheless, this substitution, especially when given at high doses, potentially shows adverse impact on fish intestinal health. This study aimed to investigate the effect of replacing fishmeal with SM on intestinal health in olive flounder (Paralichthys olivaceus). A 56-day feeding trial was conducted with 450 juvenile fish (initial weight: 6.32 ± 0.01 g) randomly allocated to five diets with graded SM replacement: 0% (FM), 12% (SM12), 24% (SM24), 36% (SM36), and 48% (SM48). The results demonstrated that concentrations of glucose, total triglyceride, and low-density lipoprotein cholesterol increased, whereas total protein and high-density lipoprotein cholesterol contents, and lysozyme activity decreased in serum with increasing dietary SM levels. Meanwhile, total antioxidant capacity and superoxide dismutase activity significantly decreased at replacement levels exceeding 24%, accompanied by elevated malondialdehyde concentration (p < 0.05). Compared with the FM group, the SM24, SM36, and SM48 groups showed significantly reduced VH and increased lamina propria width (p < 0.05). Increasing dietary SM levels upregulated expression of genes related to endoplasmic reticulum stress (ERS) (chop, perk, and grp78), inflammation (tnf-α and il-6), and apoptosis (bax, casp3, casp6, and casp9), while downregulated anti-inflammatory cytokines (il-10 and tgf-β1) and tight junction-related genes (zo-1, zo-2, claudin-5, ocln, muc-13, and muc-15) in the intestine (p < 0.05). There were significant differences in the abundances of intestinal microbiota at both the phylum and genus levels among the FM, SM24, and SM36 groups (p < 0.05), but the clusters and microbiota composition of the SM24 group were more similar to those of the FM group. In conclusion, replacing 24% of fishmeal with SM induced intestinal dysfunction through evoking ERS, inflammation, barrier disruption, and microbial dysbiosis in olive flounder.

Fusobacterium nucleatum (F. nucleatum), an anaerobic resident of the oral cavity, is increasingly recognized as a contributing factor to ulcerative colitis (UC). The adhesive properties of F. nucleatum are mediated by its key virulence protein, FadA adhesin. However, further investigations are needed to understand the pathogenic mechanisms of this oral pathogen in UC. The present study aimed to explore the role of the FadA adhesin in the colonization and invasion of oral F. nucleatum in dextran sulphate sodium (DSS)-induced colitis mice via molecular techniques. In this study, we found that oral inoculation of F. nucleatum strain carrying the FadA adhesin further exacerbated DSS-induced colitis, leading to elevated alveolar bone loss, disease severity, and mortality. Additionally, CDH1 gene knockout mice treated with DSS presented increases in body weight and alveolar bone density, as well as a reduction in disease severity. Furthermore, FadA adhesin adhered to its mucosal receptor E-cadherin, leading to the phosphorylation of β-catenin and the degradation of IκBα, the activation of the NF-κB signalling pathway and the upregulation of downstream cytokines. In conclusion, this research revealed that oral inoculation with F. nucleatum facilitates experimental colitis via the secretion of the virulence adhesin FadA. Targeting the oral pathogen F. nucleatum and its virulence factor FadA may represent a promising therapeutic approach for a portion of UC patients.

Interleukin-20 (IL-20), as an essential member of IL-10 family, plays vital roles in mammalian immunological response such as antimicrobial, inflammation, hematopoiesis, and immune diseases. In teleost, the study about immune antimicrobial function of IL-20 is largely scarce. In this article, we revealed the expression profiles and the immunological functions of the IL-20 (CsIL-20) in tongue sole Cynoglossus semilaevis. CsIL-20 is composed of 183 amino acid residues, with seven cysteine residues and a typical IL-10 domain which comprises six α-helices and two β-sheets, and shares 34.4-71.2 % identities with other teleost IL-20. CsIL-20 was constitutively expressed in a variety of tissues and regulated by bacterial invasion, and the recombinant CsIL-20 (rCsIL-20) could bind to different bacteria. In vitro rCsIL-20 could interact with the membrane of peripheral blood leukocytes (PBLs), leading to the attenuation of reactive oxygen species (ROS) production and acid phosphatase activity in PBLs. In line with In vitro results, In vivo rCsIL-20 could obviously suppressed the host immune against bacterial infection. Furthermore, knockdown of CsIL-20 in vivo could markedly enhance the host antibacterial immunity. Collectively, these observations offer new insights into the negative effect of CsIL-20 on antibacterial immunity.

Fermentation is a promising method to improve the utilization of soybean meal (SM) by fish, and strain is the core of fermentation process. In this study, the effects of Lactobacillus paracasei fermentation on the SM quality were investigated. Also, an 8-week feeding trial was conducted to compare the performance of SM and L. paracasei fermented SM (LPFSM) in diets for turbot. Juvenile turbots (13.50 ± 0.13 g) were randomly divided into nine treatments fed on diets with 0% (FM, control), 15% (S15/L15), 30% (S30/L30), 45% (S45/L45), and 60% (S60/L60) of fishmeal protein replaced by SM or LPFSM respectively. The results showed that fermentation remarkably increased the lactic acid and decreased the anti-nutritional factors in SM. Furthermore, fishmeal could be replaced by SM up to 30% or by LPFSM up to 45% based on the growth performance. Typical groups (FM, S45, and L45) with significant differences in growth were selected for further analysis. Reduced villus height and widened lamina propria were observed in the S45 group, while no significant pathological symptom was found in the L45 group. The mRNA levels of the apoptosis-related genes (bax, p53, and caspase3) and tight junction-related gene (tricellulin) in the S45 group were significantly up-regulated or down-regulated, respectively, while the L45 group remained similar to the FM group. The mRNA levels of tight junction-related genes (zo-1 and occludin) were significantly down-regulated in both S45 and L45 groups compared to the FM group. Furthermore, dietary LPFSM modified the intestinal microbiota by regulating the dominant bacterial phyla (Proteobacteria, Firmicutes, and Actinobacteria) and genera (Cobetia, Pseudomonas, and Lactobacillus), and making the overall microbiota profile more coherent with FM-fed fish. Collectively, L. paracasei fermentation significantly improved the SM quality, and fishmeal could be replaced by LPFSM up to 45% without adverse effects on growth and intestinal health of turbot.

In China, the invasive macroalga Chaetomorpha valida exerts significant negative effects on the composition of biotic communities and the balance of the ecological environment. C. valida can respond to changes in inorganic N/P ratios in the environment by regulating the activity of enzymes related to nitrogen (N) and phosphorus (P) metabolism and enhancing its N and P assimilative capacity, which may enable it to outcompete many native species. This study experimentally assessed the response of the activity of enzymes associated with N and P metabolism to different N/P ratios. Significantly higher activities of nitrate reductase, nitrite reductase, glutamate synthase and glutamine synthetase were obtained with the treatments with N/P ratios of 0/0, 2.5/1 and 5/1 ( P < 0.01). All the P concentrations tested activated the alkaline phosphatase activities of C. valida , particularly in the absence of N and P ( P < 0.01). C. valida does not experience severe effects of nutrient limitation leading to growth inhibition. This successful invasion of C. valida proves its strong adaptability to complex environments and indicates its competitive advantage over other native species in the same inorganic N and P environment.

This study was performed to investigate the fermentation efficiency of Lactobacillus acidophilus and compare the effects of dietary soybean meal (SM) or L. acidophilus -fermented SM (LASM) on turbot. Two hundred and seventy juvenile turbots (13.50 ± 0.13 g) were randomly divided into three treatments fed with a fishmeal-based diet (CNT) and two experimental diets with 45% fishmeal protein replaced by SM or LASM for 8 weeks. The results showed that fermentation significantly improved the essential amino acid profile, increased the lactic acid content, and reduced the antinutritional factor level in SM. Inferior growth of fish was observed in the SM group after the feeding trial, while the LASM group exhibited comparable performance to the CNT group. Activities of intestinal digestive enzymes (trypsin and diastase) and immune-related enzymes (alkaline phosphatase, acid phosphatase, and lysozyme) decreased significantly in the SM group, while no significant reduction was found in the LASM group compared to the CNT group. Dietary LASM alleviated SM-induced intestinal pathological disruption with higher villus and normal lamina propria width. Dietary LASM positively regulated the intestinal microbiota, making the overall profile more coherent with that in the CNT group. Spearman’s correlation analysis revealed that the altered intestinal microbiota was closely linked to the digestive enzyme activities. Collectively, this study indicated that L. acidophilus fermentation significantly improved the nutritional quality of SM and relieved SM-induced adverse effects on turbot, in terms of growth, intestinal digestive and immune-related enzyme activities, morphology, and microbiota.

The potential of the green tide macroalgae Chaetomorpha valida as a food source for Apostichopus japonicus was evaluated in this study as a solution to ease the shortage of macroalgae. Four diets were formulated and tested with juvenile A. japonicus in a laboratory simulation experiment for 6 weeks. Diets included commercial feed, Sargassum muticum, C. valida and C. valida fermentation feed. The crude protein content of the C. valida fermentation feed was similar to that of the commercial feed, and its crude fat was comparable to S. muticum. Though the energy intake of A. japonicus in the fermentation feed group was the lowest, it accounted for the highest proportion of energy for growth. The growth rate of animals fed with fermentation feed was lower than those fed commercial feed, similar to S. muticum feed, and consistent with the feed conversion efficiency for each diet. The contents of chemical oxygen demand (COD) and ammonia nitrogen of water in the fermentation feed group were the lowest. Its content of nitrite nitrogen of water also remained at a low level throughout. Overall, the fermented C. valida was a useful alternative food source of S. muticum for A. japonicus aquaculture.

Konosirus punctatus is an important species for the structure of marine ecosystems. Meanwhile, it is a native species in the northwest Pacific Ocean and supports important commercial fishery. In the present study, we generated the whole transcriptome of K. punctatus from combined tissues (muscle, liver, gill, heart, kidney, swim bladder and sexual gland) using Illumina RNA-seq technology and a total of 46087110 clean reads were obtained, corresponding to 6531521430 nucleotides. Meanwhile, 10000 clean reads were randomly selected and compared with NT database to examine the possible contamination. Results showed that 6754 clean reads were distributed among some species closely related with K. punctatus, indicating no-pollution. De novo assembly was performed and all clean reads were assembled to produce 71610 longest unigenes with an N50 of 906 bp. Among all the unigenes, 43974 unigenes were annotated in at least one database and 3172 unigenes were annotated in all databases. All unigenes were further analyzed to predict the gene structure and we have obtained a total of 54864 coding sequences (CDSs) and 17326 simple sequence repeats (SSRs). Saturation analyses were applied to evaluate the accuracy of gene expression and we hypothesized that the detection of gene expression might be effective. Finally, single-copy orthologous genes were applied to construct the phylogenetic relationship of K. punctatus. Results showed that K. punctatus diverged from the common ancestor with Alosa alosa, Alosa pseudoharengus and Sardina pilchardus at approx. 61.16-92.52 MYA. The present study will provide a foundational molecular information for the biological research of K. punctatus.