Search Results (70)

Gingivitis, periodontitis, and stomatitis are common oral inflammatory disease affecting a large proportion of the global population. Increasing attention has recently been given to the development of health functional materials aimed at maintaining oral health and preventing microbial-associated oral disease. This study evaluated the efficacy of the lipoteichoic acid (LTA) fraction derived from the probiotic Lactiplantibacillus plantarum K8 (pLF) in preventing oral inflammation and microbial infection using the oral epithelial cell line YD-38. The results confirmed that pLF enhances the expression of interleukin-1 receptor-associated kinase M (IRAK-M), a negative regulator of Toll-like receptor (TLR) signaling, and inhibits the expression of pro-inflammatory cytokines, including C-C motif ligand 2 (CCL2), interleukin-6 (IL-6), and interleukin-8 (IL-8), in YD-38 cells stimulated with tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). Furthermore, it was demonstrated that pLF induces IRAK-M expression in a TLR2-involved manner and inhibits nuclear factor-kappa B (NF-κB) signaling, thereby reducing the expression of pro-inflammatory cytokines. pLF also exhibits oral antimicrobial efficacy by increasing the expression of the antimicrobial peptide human β-defensin 1 (hBD1) and human β-defensin 2 (hBD2) in a TLR2-involved manner and effectively inhibiting the growth of Porphyromonas gingivalis and Staphylococcus aureus in the epithelial cell associated system. Therefore, the LTA fraction derived from L. plantarum K8 represents a promising postbiotic candidate for the regulation of oral immune and microbial responses. Full article

Background/Objectives: Differentiating idiopathic granulomatous mastitis (IGM) from breast cancer (BC) remains a significant clinical challenge due to overlapping clinical and radiological features. This study aimed to evaluate the diagnostic value of serum defensins and conventional tumor markers in distinguishing BC from IGM. Methods: A total of 150 participants were included: 50 with BC, 50 with IGM, and 50 with healthy controls. Serum levels of α-defensin 1, β-defensin 1, and β-defensin 2 were measured and compared across groups. In addition, inflammatory markers and tumor markers were analyzed. Receiver operating characteristic (ROC) analysis and logistic regression models were used to assess diagnostic performance. Results: Serum defensin levels were significantly higher in BC and IGM compared to healthy controls (p < 0.001), with β-defensin 2 showing the highest levels in BC. ROC analysis demonstrated high diagnostic accuracy for defensins (AUC: 0.95–0.99); however, in multivariable analysis, defensins were not retained as independent predictors, whereas CA15-3 and CA125 remained significant. The combined model based on CA15-3 and CA125 showed good discriminative performance (AUC = 0.83). Conclusions: Defensin levels, particularly β-defensin-2, were highest in BC and showed promising diagnostic potential; however, they should be considered adjunctive biomarkers. Their integration with conventional tumor markers and inflammatory parameters may improve differentiation between BC and IGM. Full article

Porcine β-defensin 2 (pBD2) possesses broad-spectrum antimicrobial properties and is crucial for gastrointestinal mucosal repair. Lactic acid bacteria (LAB) serve as optimal vectors for exogenous protein delivery due to their high biosafety, intestinal colonization capacity, and ability to modulate gut microecology. In this study, we engineered a recombinant Lactobacillus paracasei strain (pPG-N1-pBD2/27-2) that efficiently secretes pBD2. In vitro, this recombinant strain significantly enhanced the proliferation and migration of porcine intestinal epithelial cells (IPEC-J2). In vivo, oral administration of pPG-N1-pBD2/27-2 markedly alleviated dextran sulfate sodium (DSS)-induced colitis in mice. This protective effect was evidenced by reduced Disease Activity Index (DAI) scores, prevention of colon shortening, and decreased colonic activities of myeloperoxidase (MPO) and eosinophil peroxidase (EPO), alongside normalized N-acetyl-β-D-glucosaminidase (NAG) levels. Histopathological analysis revealed that the treatment preserved mucosal architecture, including goblet cells and crypts, and fortified the physical barrier by upregulating tight junction proteins. Mechanistically, the recombinant strain suppressed the colonic iNOS/COX-2 inflammatory axis, decreased serum pro-inflammatory cytokines (IL-6, IL-1β, and TNF-α), and elevated the anti-inflammatory cytokine IL-10. Furthermore, it restored systemic immune homeostasis by normalizing the proportions of splenic macrophages, T/B lymphocytes, and natural killer (NK) cells. In conclusion, pPG-N1-pBD2/27-2 mitigates colitis through a dual mechanism: reinforcing the intestinal physical barrier and rebalancing the innate–adaptive immune axis. These findings highlight the potential of pBD2-engineered probiotics as novel biological therapeutics for intestinal inflammatory diseases. Full article

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects host cells through the interaction between the spike protein receptor-binding domain (RBD) and the human angiotensin-converting enzyme 2 (hACE2) receptor, which is expressed on epithelial cells in various tissues, including the respiratory tract. Therefore, mucosal immunity in the respiratory tract plays a key role in protection against viral infection. Previously, we demonstrated that intranasal administration of antigens (Ags) conjugated with the M cell-targeting peptide Co4B enhances both mucosal and systemic immune responses. That conjugation with human β-defensin 2 (HBD2) increases neutralizing antibody (Ab) responses. Methods: A recombinant antigen conjugate incorporating both Co4B and HBD2 was designed to enhance immunogenicity. Its immunogenicity was evaluated in mice following intranasal immunization. Antigen-specific antibody responses were measured in serum and bronchoalveolar lavage fluid. T-cell responses were evaluated in lungs and spleens. Protective efficacy was assessed using SARS-CoV-2-susceptible hACE2 knock-in mice. Results: Ag-specific Ab levels increased in both serum and bronchoalveolar lavage fluid of mice immunized intranasally with the conjugate. Especially, T-cell responses were significantly enhanced in the lungs and spleens of immunized hACE2 knock-in mice. In challenge experiments, intranasal administration of the conjugate reduced viral load. Moreover, Siglec F was identified as a potential receptor for Co4B, a previously uncharacterized M cell-targeting ligand. Conclusions: A recombinant viral Ag containing Co4B and HBD2 induces virus-specific humoral and cellular immune responses. Although further optimization of the vaccine formulation and administration strategy is needed, this conjugate shows potential as a platform for improving mucosal and systemic immunity. Full article

Purpose: To investigate the mechanisms by which plasma extracellular vesicles (EVs) from preterm infants with bronchopulmonary dysplasia (BPD) elicit inflammation and abnormal angiogenesis in neonatal mouse retinas. Methods: EVs from the plasma of 7-day-old preterm infants, born between 23^0/7 and 29^6/7 weeks of gestation, with BPD or without BPD (nBPD) at 36 weeks postmenstrual ages, were adoptively transferred into postnatal day 3 (P3) mice via intravenous retro-orbital sinus injection. Inflammation and pathological neovascularization in neonatal mouse retinas were examined by immunohistochemistry of retinal flat mounts for Allograft Inflammatory Factor 1 (AIF1), CD206, or Glial Fibrillary Acidic Protein (GFAP) and isolectin-B4 (IB4) staining on P17. Retinal inflammation-related transcripts were assessed by qRT-PCR. Proteomic profiles of BPD and nBPD EVs were examined by Liquid Chromatograph Mass Spectrometer/Mass Spectrometer (LC-MS/MS) and Gene Set Enrichment Analysis (GSEA). Results: Adoptively transferred EVs from BPD and nBPD infants crossed the blood–retinal barrier (BRB) in recipient mouse pups. BPD-EVs increased retinal activated microglia, Müller cells, and twisted proliferative neovascularization compared to nBPD-EVs. BPD-EVs also elevated retinal transcripts regulating inflammation and angiogenesis, including NOD-, LRR- and pyrin domain-containing protein 3 (Nlrp3), Apoptosis-associated speck-like protein containing a caspase recruitment domain (Asc), Caspase 3 (Casp3), Caspase 8 (Casp8), Gasdermin D (Gsdmd), Il1β, Il6, Aif1, and Vascular endothelial growth factor (Vegf). Proteomics analysis revealed that BPD-EVs had significantly elevated levels of inflammation and angiogenesis-related proteins compared to nBPD-EVs. Conclusions: BPD-EVs promote inflammation and abnormal neovascularization by upregulating genes related to apoptosis and inflammation in neonatal mouse retinas. EV protein profiles suggest that elevated levels of proteins such as Defensin alpha 1B (DEFA1B), Insulin-like growth factor binding protein 2 (IGFBP2), CD5 antigen-like (CD5L), von Willebrand factor (vWF), and Tenascin C (TNC) in BPD-EVs may contribute to the observed inflammation and angiogenesis. Full article

Salmonellosis remains a persistent threat to global food safety and poultry productivity, compounded by rising antimicrobial resistance. Here, we report the in silico design and immunoinformatic validation of a broad-spectrum, edible multi-epitope vaccine targeting conserved adhesion and biofilm-associated proteins (FimH, AgfA, SefA, SefD, and MrkD) of Salmonella spp. Two constructs were engineered by integrating cytotoxic (CTL) and helper (HTL) epitopes with β-defensin-3 (HBD-3) or lipopolysaccharide (LPS) adjuvants, optimized for expression in Chlorella vulgaris. Structural modeling confirmed native-like folding (z-scores −2.58 and −5.22) and high stability indices. Molecular docking and dynamics revealed that the LPS-adjuvanted construct (Construct 2) forms a highly stable complex with Toll-like receptor 3 (HADDOCK score −63.4; desolvation energy −50.2 kcal/mol), indicating potent innate immune activation. Immune simulations predicted strong IgM-to-IgG class switching and durable humoral responses, consistent with effective antigen clearance. Codon optimization achieved high adaptability for algal expression (CAI = 0.93; GC ≈ 65%), supporting scalable microalgae-based production. Compared with current parenteral vaccines, offering a low-cost, non-invasive way to curb Salmonella in poultry, this edible vaccine platform reduces dependence on antibiotics. Our approach, which combines computational vaccinology with a safe-by-design sustainable biomanufacturing perspective, outlines a One Health framework for advancing antimicrobial stewardship and food safety. Full article

Clinical reports have shown that administration of Nauclea officinalis (Danmu in Chinese, DM) preparations may cause significant gastrointestinal discomfort. This study aimed to systematically evaluate the adverse effects of DM and its primary active constituent, strictosamide, on gastrointestinal motility, intestinal barrier integrity, and gut microbiota homeostasis. Furthermore, we sought to investigate the potential role of the bitter taste receptor (T2R) signaling pathway in mediating these effects. In vitro cell cultures and ex vivo intestinal tissues were employed to assess cell viability and molecular alterations. In vivo studies involved short-term (2 weeks) gavage of DM (0.54 and 1.08 g/kg) and long-term (16 weeks) intervention (0.4, 0.8, and 1.2 g/kg) in rodents. Evaluations included histopathological examination, serum levels of cytokines and oxidative stress markers (ELISA), expression of tight junction proteins (Western blot and qPCR), and 16S rDNA sequencing of cecal microbiota. Mechanistic analyses focused on α-defensin secretion and T2R-associated gene and protein expression. Administration of DM resulted in significant gastrointestinal dysfunction, characterized by delayed intestinal propulsion and increased gastric retention. Dose-dependent histopathological damage, disruption of the intestinal barrier (reduced occludin and claudin-1 expression), and elevated levels of pro-inflammatory cytokines (IL-6, TNF-α, and IL-1β), oxidative stress markers (MDA, SOD, and GSH-Px), and immune mediators (IFN-γ) were observed. Gut microbiota analysis revealed dysbiosis, marked by a decline in beneficial genera (e.g., Mucispirillum, Butyricicoccus, Roseburia) and an increase in potentially pathogenic bacteria (e.g., Citrobacter, Helicobacter). Mechanistically, DM suppressed α-defensin secretion and downregulated the expression of TAS2R108, TAS2R138, and Gα-gustducin both in vitro and in vivo. DM and strictosamide disrupt gut microbiota composition and compromise intestinal barrier function, likely through inhibition of the T2R/α-defensin pathway. These findings provide important mechanistic insights into drug-induced gastrointestinal toxicity and underscore the potential risks associated with prolonged use of DM-containing preparations. Full article

Cytokine storm is a critical driver of acute respiratory distress syndrome and multiple organ failure. Human β-defensin 2 (HBD-2) is the first inducible defensin discovered in human body. Defensin can resist pathogenic microorganisms invading the body through direct bactericidal effect and also modulates acquired immune response. Albumin exhibits immunomodulatory properties and can reduce the level of inflammatory cytokines to improve the systemic inflammatory response. We previously engineered a recombinant fusion protein, DF₂-HSA, comprising two HBD-2 molecules linked to human serum albumin. Here, we evaluated its effect on cytokine storm using a lipopolysaccharide (LPS)-induced cytokine storm murine model (BALB/c athymic mice, female). DF₂-HSA reduced the mortality in cytokine storm murine model and prolonged the retention time of HBD-2 in the body. A Luminex assay showed that DF₂-HSA reduced the production of multiple inflammatory cytokines in cytokine storm murine model. Evans blue staining showed that DF₂-HSA reduced vascular leakage. Transmission electron microscopy showed that DF₂-HSA reduced the lung injury of cytokine storm mice. The pathological results showed that DF₂-HSA alleviated the lung and small intestine damage of cytokine storm mice. In summary, DF₂-HSA effectively inhibits cytokine storms and ameliorates associated tissue damage. Full article

Obesity, type 2 diabetes (T2D), and insulin resistance are pervasive metabolic disorders marked by chronic low-grade inflammation and systemic metabolic disorders. The emerging field of immunometabolism highlights how interactions between immune processes and metabolic pathways in adipose tissue, liver, muscle, and pancreatic islets contribute to disease pathogenesis. Lipid dysregulation plays a central role in these processes, with distinct lipid molecules identified in obese patients as compared to lean patients that correlate with insulin resistance, inflammation, and vascular dysfunction. This Special Issue compiles a multidisciplinary body of research aimed at elucidating molecular mechanisms, identifying novel biomarkers, and exploring innovative therapeutic strategies. Key contributions include studies on omega-3 long-chain polyunsaturated fatty acids (LCPUFAs) and their differential associations with neurocognitive development; the potential of beta-defensin 2 as a biomarker linking gut-derived inflammation and metabolic dysfunction; and the promotion of adipocyte browning by Carnosic acid via AMPK activation and GSK3β inhibition. Additionally, reviews of phytochemicals underscore their multisystem therapeutic potential, while investigations into sodium–glucose cotransporter-2 (SGLT2) inhibitors suggest possible metabolic and neuroprotective benefits beyond glucose control. Maternal lipid metabolism during pregnancy and its impact on maternal fetal health further emphasize the clinical complexity of lipid dysregulation. Despite promising insights, significant gaps remain regarding causality versus correlation in lipid biomarkers, standardization of analytical methodologies, tissue heterogeneity, and unintended effects of metabolic interventions. Collectively, these studies underscore the necessity of integrative, mechanism-driven research to bridge fundamental biology with translational and clinical applications, ultimately advancing precision therapies for metabolic diseases. Full article

Lipopolysaccharide (LPS), an essential structural molecule in the outer membrane of Gram-negative bacteria, is recognized as a principal trigger of inflammatory responses and oxidative stress. Thus, the control and clearance of LPS is essential to inhibit LPS-induced excessive inflammation, oxidative stress, and liver injury. In recent years, some native bioactive peptides, such as human β-defensin 126 (DEFB126) and thymopentin (TP5), have been reported to have inhibitory effects against LPS-induced inflammation and oxidative stress. However, the cytotoxicity, weak stability, and poor biological activity have hindered their practical application and clinical development. The development of novel hybrid peptides is a promising approach for overcoming these problems. In this study, we designed a novel hybrid peptide [DTP, DEFB126 (1-39)-TP5] that combines the active center of DEFB126 and full-length thymopentin (TP5). Compared to the parental peptides, DTP has a longer half-life, lower cytotoxicity, and greater anti-inflammatory and antioxidant activity. The anti-inflammatory and antioxidant effects of DTP were demonstrated in a murine LPS-induced sepsis model, which showed that DTP successfully inhibited the indicators associated with LPS-induced liver injury; decreased the contents of TNF-α, IL-6, and IL-1β; increased the level of glutathione (GSH); and improved the activities of catalase (CAT) and superoxide dismutase (SOD). Furthermore, our study revealed that the anti-inflammatory and antioxidant activities of DTP were associated with LPS neutralization, blockade of LPS binding to the Toll-like receptor 4/myeloid differentiation factor 2 (TLR4/MD-2) complex, reduction in reactive oxygen species content, and inhibition of the activation of the nuclear factor kappa-B (NF-кB) signaling pathway. These results elucidate the structural and functional properties of the peptide DTP, reveal its underlying molecular mechanisms, and shed light on its potential as a multifunctional agent for applications in agriculture, food technology, and clinical therapeutics. Full article

This study aimed to assess whether dietary supplementation with probiotics could alleviate intestinal injury in lipopolysaccharide (LPS)-challenged piglets. Healthy weaned piglets were randomly allocated to four individual groups (n = 6): (1) a control group; (2) an LPS group; (3) an LPS + Lactobacillus group; and (4) an LPS + Bacillus group. The control and LPS groups received a basal diet, while the probiotic groups were provided with the same basal diet supplemented with 6 × 10⁶ cfu/g of Lactobacillus casei (L. casei) or a combination of Bacillus subtilis (B. subtilis) and Bacillus licheniformis (B. licheniformis) at a dosage of 3 × 10⁶ cfu/g, respectively. On day 31 of the trial, overnight-fasted piglets were killed following the administration of either LPS or 0.9% NaCl solution. Blood samples and intestinal tissues were obtained for further analysis several hours later. The results indicate that dietary supplementation with probiotics significantly exhibited health-promoting effects compared with the control group and effectively reduced LPS-induced histomorphological damage to the small intestine, impairments in barrier function, and dysregulated immune responses via modulation of enzyme activity and the expression of relevant genes, such as nuclear factor-kappa B (NF-κB), interleukin 4 (IL-4), interleukin 6 (IL-6), interleukin 10 (IL-10), claudin-1, nuclear-associatedantigenki-67 (Ki-67), and β-defensins-1 (pBD-1). Collectively, these results suggest that dietary supplementation with probiotics could alleviate LPS-induced intestinal injury by enhancing the immunity and anti-inflammatory responses in piglets. Our research provides a theoretical basis for the rational application of probiotics in the future. Full article

Defensins, one of the members of the antimicrobial peptide family, play a vital role in resisting microbial invasion and immune regulation. Porcine β-defensin 2 possesses excellent stability, making it an ideal antibiotic alternative for feed additives. In this study, a total of 15 piglets were used to investigate the effects of supplementing diets with 2.5 mg/kg (LP group) and 5 mg/kg (HP group) of pBD2 to weaned piglets. The results revealed that pBD2 significantly increased the total weight gain and average daily weight gain (p < 0.05), the contents of T-AOC, SOD, IgM, and IL-10 in serum (p < 0.05), the villus-to-crypt ratios, and the expression of tight-junction proteins ZO-1 and claudin-1 (p < 0.05) in the small intestine. Furthermore, pBD2 increased the abundance of beneficial bacteria related to nutrient and energy metabolism while decreasing the abundance of harmful bacteria associated with intestinal inflammation and diarrhea. Alterations in the gut microbiota were closely associated with the levels of T-AOC, SOD, IgM, and IL-10 in serum. pBD2 primarily enhanced the health of weaned piglets by influencing antioxidant capacity, intestinal barrier function, and the intestinal microbiota. Our research provides a novel perspective for addressing the issue of antibiotic residues in feed. Full article

Enterotoxigenic Escherichia coli (ETEC), a common intestinal pathogen, can colonize the intestines and induce diarrhea in piglets, which brings great economic losses to the swine industry. Antibiotics are recommended to the treatment for diarrhea caused by ETEC in weaned piglets. However, with the emergence and spread of multidrug-resistant ETEC, there is an urgent need to develop alternatives to antibiotics. Due to the unique antibacterial mechanism of targeting bacterial membranes, antimicrobial peptides (AMPs) are promising candidates. In this study, the activity of crude recombinant porcine β-defensin 2 (rPBD2) expressed in Pichia pastoris (P. pastoris) was measured in vitro. Mice infected with ETEC were orally administered 16, 8, and 4 AU crude rPBD2 for 7 consecutive days to evaluate its anti-infective activity in vivo. The results showed that in addition to broad antibacterial activity against Gram-positive and -negative bacteria, crude rPBD2 displayed high tolerance to temperatures ranging from 20 to 60 °C, a broad range of pH, trypsin, pepsin, and physiological concentrations of salts. In an ETEC-induced mouse model, the oral administration of crude rPBD2 decreased diarrhea scores and the intestinal/carcass ratio and alleviated body weight loss. Additionally, crude rPBD2 decreased bacterial loads in stools and the colon (HP group), and the levels of serum pro-inflammatory cytokines IL-6 (HP group) and TNF-α (HP and MP groups), and increased the villus height and the ratio of villus height to crypt depth (VH/CD) in the ileum (HP and MP groups). Our study provides a cost-effective way for PBD2 production and identifies it as a promising candidate to combat ETEC-induced infection. Full article

(1) The aim of this study was to elucidate the role of the Gallus gallus avian β-defensin 11 (AvBD11) in the immune response induced by the avian influenza virus H9N2. (2) AvBD11 was expressed using E. coli, and the effects of different concentrations of AvBD11 on cytokine expression in the ex vivo and in vivo erythrocytes of chickens infected with the avian influenza subtype H9N2 were detected by using fluorescence quantification. (3) The results showed that cytokine expression varied among the test groups compared to the control group in the in vitro assay at 2, 6, and 10 h. Lipopolysaccharide induced TNF factor (LITAF) and Interferon-γ (IFN-γ) were significantly increased in the AvBD11 group with the addition of the final concentration of 15 μg/mL at 6 h. At 10 h, Interleukin-1β (IL-1β) and IFN-γ were both more significantly increased in the 15 and 10 μg/mL groups than in the H9N2 group alone. In the in vivo test, IFN-γ and Interleukin-10 (IL-10) were significantly increased in the high-dose group than in the H9N2 group at 3 d and 7 d. (4) In conclusion, the ability of AvBD11 to induce the expression of more cytokines by chicken erythrocytes in a short period of time suggests that it is not only an antimicrobial peptide but also a possible immunomodulator. Full article

The physiological functions of newborn calves are undeveloped, especially the immune system, making them susceptible to infections. In recent years, the theory of trained immunity has attracted attention and provided new strategies to prevent unknown infections in animals. This study investigated the effects of feeding yeast β-glucan on the intestinal and respiratory health of calves during the suckling period. Newborn Holstein calves (average birth weight: 36.18 ± 0.61 kg, mean ± SE) were randomly assigned to two groups: the PO (Per Os) group (n = 22) and the CON (Control) group (n = 22). Calves in the PO group were fed a yeast β-glucan solution (0.1 g/mL, 65 mg/kg body weight) at 3 and 6 days of age, respectively, while calves in the CON group received equal volumes of sterile saline orally at the same time. Blood and fecal samples were collected at 7 and 30 days of age, respectively. The results showed that (1) Compared to the CON group, being fed yeast β-glucan resulted in an inflammatory response after 24 h of the second administration, including increased gene expression of interleukin-6 (IL-6, p < 0.01), interleukin-1 beta (IL-1β, p < 0.01), and malonaldehyde (MDA, p < 0.001) content. Also, stimulation with β-glucan increased the concentrations of secreted immunoglobulin A (sIgA, p < 0.01) and defensins (p < 0.05) in the rectal feces. (2) Pre-stimulation with yeast β-glucan effectively reduced the incidence of diarrhea (p < 0.05) and bovine respiratory disease (BRD, p < 0.05) from day 31 to day 60. (3) At 30 days of age, the pre-stimulated calves had significantly lower serum DAO (p < 0.001) and MDA levels (p < 0.05), while they had higher levels of serum IL-6 (p < 0.01) and fecal slgA (p < 0.05) than calves in the CON group. (4) Pre-stimulation with yeast β-glucan altered the intestinal bacterial community; the Beta diversity results showed that the CON group and the PO group were clustered separately in the principal coordinate analysis (PCoA) graph. Obviously, the PO group sample points were more clustered. In conclusion, this study highlights the potential of yeast β-glucan-induced trained immunity to improve calf health during the suckling period. The findings offer new insights into the prevention of intestinal and respiratory infections in calves. Full article