Porcine Epidemic Diarrhea Virus (PEDV) poses a significant threat to neonatal piglets, particularly due to the limited efficacy of existing vaccines and the scarcity of efficacious therapeutic drugs. Gegen Qinlian Decoction (GQD) has been employed for over two millennia in treating infectious diarrhea. Nonetheless, further scrutiny is required to improve the drug\'s efficacy and elucidate its underlying mechanisms of action. In this study, a modified GQD (MGQD) was developed and demonstrated its capacity to inhibit the replication of PEDV. Animal trials indicated that MGQD effectively alleviated pathological damage in immune tissues and modulated T-lymphocyte subsets. The integration of network analysis with UHPLC-MS/MS facilitated the identification of active ingredients within MGQD and elucidated the molecular mechanisms underlying its therapeutic effects against PEDV infections. In vitro studies revealed that MGQD significantly impeded PEDV proliferation in IPEC-J2 cells, promoting cellular growth via virucidal activity, inhibition of viral attachment, and disruption of viral biosynthesis. Furthermore, MGQD treatment led to increased expression levels of IFN-α, IFN-β, and IFN-λ3, while concurrently decreasing the expression of TNF-α, thereby enhancing resistance to PEDV infection in IPEC-J2 cells. In conclusion, our findings suggest that MGQD holds promise as a novel antiviral agent for the treatment of PEDV infections.

Di(2-ethylhexyl) phthalate (DEHP) is a plasticizer that can damage various organizations and physiques through oxidative stress. Quercetin (Que) is a rich polyphenol flavonoid with good anti-inflammatory and antioxidant effects. However, the protection mechanism of Que against DEHP exposure-induced IPEC-J2 cell injury and the implication of autophagy, apoptosis and immunity are still unclear. In this experiment, we looked into the toxicity regime of DEHP exposure on IPEC-J2 cells and the antagonistic function of Que on DEHP. In the experiment, 135 μM DEHP and/or 80 μM Que were used to treat the IPEC-J2 cells for 24 h. Experiments indicated that DEHP exposure can cause increased reactive oxygen species (ROS) levels leading to oxidative stress, decreased CAT, T-AOC and GSH-Px activities, increased MDA and H2O2 accumulation, activated the ASK1/JNK signalling pathway, and further increases in the levels of apoptosis markers Bax, Caspase3, Caspase9, and Cyt-c, while reduced the Bcl-2 expression. DEHP also increased the expression of genes linked to autophagy (ATG5, Beclin1, LC3), while decreasing the expression of P62. Additionally, DEHP exposure led to elevated levels of IL1-β, IL-6, MCP-1, and TNF expression. When exposed to Que alone, there were no significant changes in cellular oxidative stress level, ASK1/JNK signalling pathway expression level, apoptosis, autophagy and cellular immune function. The combination of DEHP and Que treatment remarkably decreased the proportion of autophagy and apoptosis, and recovered cellular immunity. In summary, Que can attenuate DEHP-induced apoptosis and autophagy in IPEC-J2 cells by regulating the ROS/ASK1/JNK signalling pathway and improving the immune dysfunction of IPEC-J2 cells.

Antimicrobial peptides (AMPs) function to extensively suppress various problematic factors and are considered a new alternative for improving livestock health and enhancing immunomodulation. In this study, we explored whether AMP regulation has positive influences on Ochratoxin A (OTA) exposure using a porcine intestinal epithelial cell line (IPEC-J2 cells). We constructed a beta-defensin 1 (DEFB1) expression vector and used it to transfection IPEC-J2 cells to construct AMP overexpression cell lines. The results showed that OTA induced cytotoxicity, decreased cell migration, and increased inflammatory markers mRNA in IPEC-J2 cells. In DEFB1 overexpressing cell lines, OTA-induced reduced cell migration and increased inflammatory markers mRNA were alleviated. Additionally, a natural product capable of inducing DEFB1 expression, which was selected through high-throughput screening, showed significant alleviation of cytotoxicity, cell migration, and inflammatory markers compared to OTA-treated IPEC-J2 cells. Our finding provides novel insights and clues for the porcine industry, which is affected by OTA exposure.

Deoxynivalenol (DON) is a mycotoxin produced by Fusarium graminearum, and curcumin (CUR) is a natural polyphenolic compound found in turmeric. However, the combined treatment of CUR and DON to explore the mitigating effect of CUR on DON and their combined mechanism of action is not clear. Therefore, in this study, we established four treatment groups (CON, CUR, DON and CUR + DON) to investigate their mechanism in the porcine intestinal epithelial cells (IPEC-J2). In addition, the cross-talk and alleviating potential of CUR interfering with DON-induced cytotoxic factors were evaluated by in vitro experiments; the results showed that CUR could effectively inhibit DON-exposed activated TNF-α/NF-κB pathway, attenuate DON-induced apoptosis, and alleviate DON-induced endoplasmic reticulum stress and oxidative stress through PERK/CHOP pathways, which were verified at both mRNA and protein levels. In conclusion, these promising findings may contribute to the future use of CUR as a novel feed additive to protect livestock from the harmful effects of DON.

UNASSIGNED: As a symbiotic probiotic for the host, Clostridium butyricum (CB) has the potential to strengthen the body\'s immune system and improve intestinal health. However, the probiotic mechanism of CB is not completely understood. The Clostridium butyricum CBX 2021 strain isolated by our team from a health pig independently exhibits strong butyric acid production ability and stress resistance. Therefore, this study comprehensively investigated the efficacy of CBX 2021 in pigs and its mechanism of improving pig health.
UNASSIGNED: In this study, we systematically revealed the probiotic effect and potential mechanism of the strain by using various methods such as microbiome, metabolites and transcriptome through animal experiments in vivo and cell experiments in vitro.
UNASSIGNED: Our in vivo study showed that CBX 2021 improved growth indicators such as daily weight gain in weaned piglets and also reduced diarrhea rates. Meanwhile, CBX 2021 significantly increased immunoglobulin levels in piglets, reduced contents of inflammatory factors and improved the intestinal barrier. Subsequently, 16S rRNA sequencing showed that CBX 2021 treatment implanted more butyric acid-producing bacteria (such as Faecalibacterium) in piglets and reduced the number of potentially pathogenic bacteria (like Rikenellaceae RC9_gut_group). With significant changes in the microbial community, CBX 2021 improved tryptophan metabolism and several alkaloids synthesis in piglets. Further in vitro experiments showed that CBX 2021 adhesion directly promoted the proliferation of a porcine intestinal epithelial cell line (IPEC-J2). Moreover, transcriptome analysis revealed that bacterial adhesion increased the expression of intracellular G protein-coupled receptors, inhibited the Notch signaling pathway, and led to a decrease in intracellular pro-inflammatory molecules.
UNASSIGNED: These results suggest that CBX 2021 may accelerate piglet growth by optimizing the intestinal microbiota, improving metabolic function and enhancing intestinal health.

UNASSIGNED: Porcine deltacoronavirus (PDCoV), an emerging swine enteropathogenic coronavirus with worldwide distribution, mainly infects newborn piglets with severe diarrhea, vomiting, dehydration, and even death, causing huge economic losses to the pig industry. However, the underlying pathogenic mechanisms of PDCoV infection and the effects of PDCoV infection on host transcripts and metabolites remain incompletely understood.
UNASSIGNED: This study investigated a combined transcriptomic and metabolomic analysis of porcine intestinal epithelial cells (IPEC-J2) following PDCoV infection by LC/MS and RNA-seq techniques. A total of 1,401 differentially expressed genes and 254 differentially accumulated metabolites were detected in the comparison group of PDCoV-infected vs. mock-infected.
UNASSIGNED: We found that PDCoV infection regulates gene sets associated with multiple signaling pathways, including the neuroactive ligand-receptor interaction, cytokine-cytokine receptor interaction, MAPK signaling pathway, chemokine signaling pathway, ras signaling pathway and so on. Besides, the metabolomic results showed that biosynthesis of cofactors, nucleotide metabolism, protein digestion and absorption, and biosynthesis of amino acid were involved in PDCoV infection. Moreover, integrated transcriptomics and metabolomics analyses revealed the involvement of ferroptosis in PDCoV infection, and exogenous addition of the ferroptosis activator erastin significantly inhibited PDCoV replication. Overall, these unique transcriptional and metabolic reprogramming features may provide a better understanding of PDCoV-infected IPEC-J2 cells and potential targets for antiviral treatment.

BACKGROUND: The intestinal epithelium performs essential physiological functions, such as nutrient absorption, and acts as a barrier to prevent the entry of harmful substances. Mycotoxins are prevalent contaminants found in animal feed that exert harmful effects on the health of livestock. Zearalenone (ZEA) is produced by the Fusarium genus and induces gastrointestinal dysfunction and disrupts the health and immune system of animals. Here, we evaluated the molecular mechanisms that regulate the effects of ZEA on the porcine intestinal epithelium.
RESULTS: Treatment of IPEC-J2 cells with ZEA decreased the expression of E-cadherin and increased the expression of Snai1 and Vimentin, which induced Snail1-mediated epithelial-to-mesenchymal transition (EMT). In addition, ZEA induces Snail-mediated EMT through the activation of TGF-β signaling. The treatment of IPEC-J2 cells with atractylenolide III, which were exposed to ZEA, alleviated EMT.
CONCLUSIONS: Our findings provide insights into the molecular mechanisms of ZEA toxicity in porcine intestinal epithelial cells and ways to mitigate it.

The increasing prevalence of antimicrobial resistance against zoonotic bacteria, including Streptococcus (S.) suis, highlights the need for new therapeutical strategies, including the repositioning of drugs. In this study, susceptibilities of bacterial isolates were tested toward ten different 3-amidinophenyalanine (Phe(3-Am)) derivatives via determination of minimum inhibitory concentration (MIC) values. Some of these protease inhibitors, like compounds MI-432, MI-471, and MI-476, showed excellent antibacterial effects against S. suis. Their drug interaction potential was investigated using human liver microsomal cytochrome P450 (CYP450) measurements. In our work, non-tumorigenic IPEC-J2 cells and primary porcine hepatocytes were infected with S. suis, and the putative beneficial impact of these inhibitors was investigated on cell viability (Neutral red assay), on interleukin (IL)-6 levels (ELISA technique), and on redox balance (Amplex red method). The antibacterial inhibitors prevented S. suis-induced cell death (except MI-432) and decreased proinflammatory IL-6 levels. It was also found that MI-432 and MI-476 had antioxidant effects in an intestinal cell model upon S. suis infection. Concentration-dependent suppression of CYP3A4 function was found via application of all three inhibitors. In conclusion, our study suggests that the potential antiviral Phe(3-Am) derivatives with 2\',4\' dichloro-biphenyl moieties can be considered as effective drug candidates against S. suis infection due to their antibacterial effects.

Deoxynivalenol (DON) contamination in feed is a global concern that severely threatens the health of animals and humans. Taxifolin (TA) is a natural flavonoid, a member of the polyphenols, that possesses robust antioxidant properties. This study aimed to investigate the effect of TA on DON-induced damage in porcine intestinal epithelial cells (IPEC-J2). The cells were pre-incubated with a series of concentrations of TA for 24 h and exposed to DON (0.5 μg/mL) for another 24 h. The results showed that pretreatment with TA (150 μM) significantly inhibited the DON-induced decline in cell viability (p < 0.05) and cell proliferation (p < 0.01). Additionally, 150 μM TA also alleviated DON-induced apoptosis (p < 0.01). Moreover, TA decreased the production of reactive oxygen species (ROS) induced by DON (p < 0.01). In addition, TA attenuated DON-induced cell junction damage (p < 0.05). Further experiments showed that TA reversed the DON-induced reduction in antioxidant capacity in the IPEC-J2 cells, probably via activating the Nrf2 signaling pathway (p < 0.05). Collectively, these findings suggest that 150 μM TA can protect against 0.5 μg/mL DON-induced damage to IPEC-J2 cells, potentially via the activation of the Nrf2 signaling pathway. This study provides insight into TA\'s potential to act as a green feed additive in the pig farming industry and its efficacy in counteracting DON-induced intestinal damage.

Deoxynivalenol (DON) poses a serious global food safety risk due to its high toxicity and contamination rate. It disrupts the intestinal epithelial barrier, allowing exogenous toxins to enter the circulation and resulting in sepsis and systemic toxicity. In this research, 32 male Kunming mice and Porcine Small Intestinal Epithelial (IPEC-J2) cells were treated with DON at 0-4.8 mg/kg (7 d) and 0-12 μM (24 h), respectively. Histopathological results revealed that DON disrupted the intestinal epithelial barrier, causing apoptosis and tight junction (TJ) injury. Immunofluorescence and protein expression results showed that DON-induced p53-dependent mitochondrial pathway apoptosis and fibrillar actin (F-actin)-associated TJ injury and that the RhoA/ROCK pathway were activated in mice jejunal tissue and IPEC-J2 cells. Pretreatment with RhoA or ROCK inhibitors (Rosin or Y-27632) maintained DON-induced apoptosis and F-actin-associated TJ injury in IPEC-J2 cells. Thus, DON induces damage to the intestinal epithelial barrier through the RhoA/ROCK pathway-mediated apoptosis and F-actin-associated TJ disruption.