Search Results (936)

Several studies have demonstrated that methionine supplementation in fish diets enhances immune status, inflammatory response, and resistance to bacterial infections by modulating for DNA methylation, aminopropylation, and transsulfuration pathways. However, the immunomodulatory effects of methionine in viral infections remain unexplored. This study aimed to evaluate the effect of methionine supplementation on immune modulation and resistance to the viral haemorrhagic septicaemia virus (VHSV) in rainbow trout (Oncorhynchus mykiss). Two diets were formulated and fed to juvenile rainbow trout for four weeks: a control diet (CTRL) with all nutritional requirements, including the amino acid profile required for the species, and a methionine-supplemented diet (MET), containing twice the normal requirement of DL-methionine. After feeding, fish were bath-infected with VHSV, while control fish were exposed to a virus-free bath. Samples were collected at 0 (after feeding trial), 24, 72, and 120 h post-infection for the haematological profile, humoral immune response, oxidative stress, viral load, RNAseq, and gene expression analysis. In both diets, results showed a peak in viral activity at 72 h, followed by a reduction in viral load at 120 h, indicating immune recovery. During the peak of infection, leukocytes, thrombocytes, and monocytes migrated to the infection site, while oxidative stress biomarkers (superoxide dismutase glutathione S-transferase, and glutathione redox ratio) suggested a compromised ability to manage cellular imbalance due to intense viral activity. At 120 h, immune recovery and homeostasis were observed due to an increase in the amount of nitric oxide, GSH/GSSG levels, leukocyte replacement, monocyte influx, and a reduction in the viral load. When focusing on the infection peak, gene ontology (GO) analysis showed several exclusively enriched pathways in the skin and gills of MET-fed fish, driven by the upregulation of several key genes. Genes involved in recognition/signalling, inflammatory response, and other genes with direct antiviral activity, such as TLR3, MYD88, TRAF2, NF-κB, STING, IRF3, -7, VIG1, caspases, cathepsins, and TNF, were observed. Notably, VIG1 (viperin), a key antiviral protein, was significantly upregulated in gills, confirming the modulatory role of methionine in inducing its transcription. Viperin, which harbours an S-adenosyl-L-methionine (SAM) radical domain, is directly related to methionine biosynthesis and plays a critical role in the innate immune response to VHSV infection in rainbow trout. In summary, this study suggests that dietary methionine supplementation can enhance a more robust fish immune response to viral infections, with viperin as a crucial mediator. The improved antiviral readiness observed in MET-fed fish underscores the potential of targeted nutritional adjustments to sustain fish health and welfare in aquaculture. Full article

Tauroursodeoxycholic acid (TUDCA), a bile acid conjugate, has been suggested to improve cognition in models of Alzheimer’s disease (AD), although its underlying mechanisms remain unclear. This study aimed to evaluate the effects of TUDCA and its potential pathways in APP/PS1 mice. Behavioral tests, assessments of amyloid-β (Aβ) deposition, neuroinflammation, peripheral inflammatory responses, intestinal barrier integrity, and gut microbiota composition were performed, along with pseudo-sterile mouse experiments and fecal microbiota transplantation (FMT). The expression of genes related to the TLR4/NF-κB/NLRP3 pathway was also examined. TUDCA significantly ameliorated cognitive impairments, reduced Aβ accumulation, and suppressed inflammatory responses in both the central nervous system and peripheral tissues. It improved intestinal barrier function and reshaped gut microbial composition by reducing pro-inflammatory taxa. FMT demonstrated that TUDCA-modulated microbiota contributed to improved learning and memory in AD mice, whereas antibiotic-induced pseudo-sterility indicated that TUDCA also exerted cognitive benefits independent of gut flora. Moreover, TUDCA inhibited the activation of the TLR4/NF-κB/NLRP3 pathway. In conclusion, TUDCA alleviates AD-related cognitive deficits partly through modulation of the microbiota–gut–brain axis while also acting via microbiota-independent mechanisms, supporting its potential as a promising therapeutic strategy for AD. Full article

Acute pancreatitis (AP) is a severe inflammatory disorder characterized by a complex molecular pathophysiology involving premature zymogen activation, organelle dysfunction, and systemic immune dysregulation. Current therapeutic strategies remain largely supportive, underscoring the critical need for specific molecular-targeted interventions. Baicalein, a bioactive flavonoid derived from Scutellaria baicalensis Georgi, has emerged as a potent pleiotropic agent. This review comprehensively synthesizes the molecular mechanisms underlying baicalein’s therapeutic efficacy in AP. Its capacity to intercept the pathological cascade at multiple checkpoints is elucidated, from mitigating the initiating cytosolic calcium overload and preserving mitochondrial integrity to suppressing the cytokine storm via the TLR4/NF-κB/MAPK signaling axis. Crucially, baicalein modulates the pancreatic immune microenvironment by driving the phenotypic polarization of macrophages from pro-inflammatory M1 to reparative M2 states and regulating neutrophil dynamics, specifically by inhibiting infiltration and neutrophil extracellular trap formation. Furthermore, its role in orchestrating regulated cell death pathways is highlighted, specifically by blocking pyroptosis and ferroptosis while modulating apoptosis, and its function as a biophysical scavenger of circulating histones and pancreatic lipase to neutralize systemic toxins. Consequently, this review emphasizes the multi-target biological activities of baicalein, providing a mechanistic rationale for its development as a precision therapeutic candidate for AP. Full article

Parkinson’s disease is a neurodegenerative disorder that affects the elderly population worldwide. Rotenone (ROT) is an environmental toxin that impairs mitochondrial dynamics by inhibiting respiratory chain complex I and thus inducing oxidative stress. Farnesol (FSL) is a dietary sesquiterpene with antioxidant and anti-inflammatory properties reported in various in vivo models. To evaluate the efficacy of FSL in the management of PD, Wistar rats were injected with ROT (2.5 mg/kg, i.p) and pretreated with FSL. Immunohistochemical staining measured tyrosine hydroxylase-positive cells in the substantia nigra and striatum. Western blotting was employed to determine protein expression of inflammatory, apoptotic, and autophagic markers. Our results indicate that FSL significantly protected against ROT-induced inflammation by suppressing microglial and astrocytic activation through the downregulation of Toll-Like receptor 4 (TLR4), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), inhibitor of kappa B (IkB), inducible nitric oxide synthase (iNOS), cyclooxygenase (COX), matrix metalloproteinase-9 (MMP-9) expression. FSL has also demonstrated an antioxidant effect by enhancing the activity of superoxide dismutase and catalase while reducing the level of Malondialdehyde and nitric oxide. Moreover, it restored homeostasis in ROT-induced imbalance between pro- and anti-apoptotic proteins. Impaired autophagy observed in ROT-injected rats was corrected by FSL treatment, which upregulated phosphorylated mammalian target of rapamycin (p-mTOR) expression and downregulated P62, an autophagosome marker. The protective effect of FSL was further supported by preserving the brain-derived neurotrophic factor (BDNF) and tyrosine hydroxylase in the brain. These findings demonstrate the neuroprotective ability of FSL and its potential to be developed as a pharmaceutical or nutraceutical agent for the prevention and treatment of PD by mitigating neuropathological changes observed in dopaminergic neurodegeneration. Full article

Ziziphus jujuba is an important source of polysaccharides in food supply, and studies have demonstrated that polysaccharides serve as the principal active constituents responsible for immunomodulatory effects. The results indicated that “Huizao” polysaccharides (HP2-1) increased the viability and phagocytic activity of RAW264.7 cells and triggered immune responses by promoting cytokines TNF-α, IL-6, and IL-1β secretion, as well as NO and ROS production. In addition, HP2-1 also stimulated cytokine production, elevated immunoglobulin levels, and alleviated oxidative stress via increasing antioxidant enzyme activities and reducing MDA production in immunosuppressed mice. Furthermore, HP2-1 potentiated immune responses both in vitro and in vivo by modulating the TLR4/MAPK/NF-κB pathway due to upregulating TLR4 expression, leading to phosphorylation of ERK, JNK, and p38 MAPKs, thereby activating NF-κB and subsequent cytokine secretion. Full article

Lidocaine, an amide-type regional anesthetic, has been an important medication in the field of anesthesia since its clinical approval. Recently, lidocaine has emerged as a powerful immunomodulatory agent beyond its classical anesthetic properties. This review has summarized the recent basic and clinical studies with sufficient evidence on the multifaceted effects of lidocaine on both innate and adaptive immune cells, including macrophages, neutrophils, eosinophils, basophils, natural killer (NK) cells, mast cells, dendritic cells (DCs), monocytes, and T lymphocytes. We have also detailed how lidocaine affects critical cellular processes, such as cellular polarization, cytokine production, phagocytosis, and apoptosis, through multiple signaling pathways, including NF-κB, TLR4/p38 MAPK, voltage-sensitive sodium channels, HIF1α, TGF-β/Smad3, AMPK-SOCS3, TBK1-IRF7, and G protein-coupled receptors. These immunoregulatory effects of lidocaine are dependent on its concentration, duration of action, and the microenvironment. The immunomodulatory actions of lidocaine may contribute to its potential therapeutic value in various settings of diseases, such as cancer, sepsis, acute lung injury, asthma, organ transplantation, ischemia–reperfusion injury (IRI), and diabetes. We propose that lidocaine can be repurposed as an immunomodulator for treating immune-mediated inflammatory diseases. However, future research should define optimal dosing strategies, validate its mechanisms of action in clinical trials, and explore its novel clinical applications as a complementary immunotherapy. Full article

Despite antiretroviral therapy, HIV proteins, such as Tat, persist in tissues, driving chronic inflammation. Cervical inflammation in females not only accelerates HIV progression but also increases the risk of other STIs; hence, understanding the underlying factors/regulators is vital. However, Tat-induced cervical inflammation and its regulation are hitherto poorly understood, which we investigated using TZM-bl cells. Tat stimulation in these cervical epithelial cells significantly increased the expression of various inflammatory mediators, including cytokines (IL-1β, TNF-α, IL-6, IL-17a, GM-CSF), chemokines (MIP-1α, MIP-1β), adhesion molecules (ICAM-1, P-Selectin, E-Selectin), and ROS. Further upregulation of inflammatory mediators (NF-κB, IRAK-4) along with TLR7 was observed in Tat-stimulated cells. Interestingly, Tat stimulation decreased miR-204-5p expression in these cells, suggesting a role in regulating Tat-mediated inflammatory processes. Using a gain-of-function approach, we further observed that the overexpression of miR-204-5p reduced the expression of IL-1β, TNF-α, IL-6, MIP-1α, MIP-1β, ICAM-1, P-Selectin, and ROS in the Tat-stimulated TZM-bl cells, along with NF-κB, IRAK-1, and IRAK-4. Using Western blotting and luciferase assays, miR-204-5p was further shown to directly target NF-κB. Here, we report that HIV-1 Tat stimulation in cervical epithelial cells downregulates hsa-miR-204-5p, thereby activating the pro-inflammatory TLR7/NF-κB axis, highlighting its relevance to understanding mechanisms underlying cervical inflammation. Full article

In intensive farming systems, broilers are exposed to various stressors that trigger immune stress. Reduced glutathione is known to play a crucial role in modulating immune function. This study investigated the effects of different doses of reduced glutathione on the growth performance, intestinal immune function, and gut microbiota of broilers under immune stress. One-day-old broilers were randomly assigned to five groups: group K (control), group L (lipopolysaccharide), and three glutathione supplementation groups, Y1 (50 mg/kg), Y2 (100 mg/kg), and Y3 (200 mg/kg). Each group had four replicates, with 11 broilers per replicate. On days 16, 18, and 20, broilers in groups L and Y1-Y3 received intraperitoneal injections of 0.5 mg/kg of lipopolysaccharide, while group K received an equal volume of saline. On day 16, the average daily weight gain and final body weight of group Y3 were significantly higher than those of groups K and L, whereas on day 21, the average daily weight gain of group Y3 was still significantly higher than that of group L. On day 21 broilers were slaughtered, and samples were collected. In the jejunal mucosa, group Y3 showed significantly reduced levels of IL-2, IL-4, IL-1β, and TNF-α compared to group L. Additionally, group Y3 exhibited reduced relative expression levels of NF-κB, TLR4, IFN-γ, IL-1β, IL-6, IL-4, TNF-α, and IL-2 mRNA; a decreased abundance of Enterococcus, Proteobacteria, and Actinobacteria; and a restored abundance of Ligilactobacillus, Turicibacter, and Firmicutes to normal levels. These findings suggest that 200 mg/kg of reduced glutathione is the optimal dose for improving the gut microbiota composition and mitigating gut damage caused by immune stress by inhibiting the TLR4/NF-κB signaling pathway. Full article

Background. Contributions of tumor-derived extracellular vesicles, TEX, to tumor progression and metastasis involve their crosstalk with immune cells in the tumor microenvironment. This crosstalk results in metabolic reprogramming of immune cells from anti-tumor to pro-tumor activity. Mechanistic underpinnings of the TEX entry and delivery of molecular signals responsible for metabolic reprogramming may be unique for different types of immune cells. Methods. An in vitro model of THP-1 myeloid cells co-incubated with TEX illustrates the role TEX play in polarization of macrophages to TAMs. Results. In THP-1 cells, the dominant signaling pathway of melanoma cell-derived TEX involves HSP-90/TLR2. This leads to activation of the NF-κB and MAP kinase pathways and initiates THP-1 cell polarization from M0 to M2 with strong expression of immunosuppressive PD-L1. TEX may be seen as “danger” by the myeloid cells, which utilize the pattern recognition receptors (PRR), such as PAMPs or DAMPs, for engaging the complementary ligands carried by TEX. The same melanoma TEX signaling to T cells via DAMPs induced mitochondrial stress, resulting in T-cell apoptosis. Conclusions. As the signaling receptors/ligands in TEX are determined by the tumor, it appears that the tumor equips TEX with an address recognizing specific PRRs expressed on different recipient immune cells. Thus, TEX, acting like pathogens, are equipped by the tumor to alter the context of intercellular crosstalk and impose a distinct autophagy-not-apoptosis signature in recipient THP-1 cells. The tumor might endorse TEX to promote tumor progression and metastasis by enabling them to engage the signaling system normally used by immune cells for defense against pathogens. Full article

Salmonella typhimurium (S.T) infection of the central nervous system (CNS) induces severe inflammation, leading to elevated expression of inducible nitric oxide synthase (iNOS) in microglia. This process catalyzes excessive production of nitric oxide (NO), resulting in irreversible damage to neuronal mitochondria. Asiatic acid (AA) is a small molecule with neuroprotective potential; however, its ability to counteract nerve injury induced by S.T and the underlying mechanisms remain unclear. In this study, we established an S.T-infected mouse model (in vivo) and an S.T-stimulated microglial model using BV-2 cells (in vitro) and employed techniques including immunofluorescence (IF), Western blot, co-immunoprecipitation (Co-IP), and RNA extraction and quantitative reverse transcription PCR (RT-qPCR) to systematically evaluate the protective effects and mechanisms of AA. The results showed that pre-treatment with AA significantly reduced the expression of iNOS and the production of NO caused by S.T infection in mouse hippocampal tissue and BV-2 cells. Mechanistically, AA exerts its effects by inhibiting the upstream Toll-like receptor 2 (TLR2)/Notch and nuclear factor-κB (NF-κB) signaling axis. It interferes with the nuclear translocation of Notch and p65 proteins and their complex formation under S.T stimulation, thereby blocking downstream expression of iNOS and production of NO. This study reveals a novel mechanism by which AA alleviates infection-related neuroinflammation through targeting Notch-p65 interactions, providing a new theoretical basis for its clinical application. Full article

Acute kidney injury (AKI) is a critical clinical syndrome characterized by a rapid decline in renal function, frequently resulting from ischemia, nephrotoxicity, or sepsis. It represents a major global health burden due to its high morbidity and mortality and its strong association with progression to chronic kidney disease. In this study, we identified a novel small-molecule TLR4 inhibitor, DB03476, via structure-based virtual screening targeting the intracellular TIR domain of murine Tlr4. Molecular dynamics simulations confirmed that DB03476 stabilizes Tlr4 without altering its global conformation. In a murine ischemia–reperfusion-induced AKI model, DB03476 administration significantly attenuated renal inflammation, macrophage infiltration, and apoptosis and suppressed the TLR4/MyD88/NF-κB pathway. Moreover, DB03476 exhibited cross-species efficacy by binding conserved residues in human TLR4 with high affinity. Functional validation using human kidney organoids confirmed its protective effects against inflammatory challenge. These results demonstrate DB03476 as a promising therapeutic agent for AKI through selective inhibition of TLR4-mediated inflammatory responses. Full article

The objective of this study was to investigate the effects of replacing fishmeal with H. illucens larval meal on the colonic immune homeostasis in weaned piglets in enterotoxigenic Escherichia coli (ETEC)-challenged pig housing. Seventy-two weaned piglets, aged 28 days, were randomly divided into three groups for dietary treatment: the basal diet (negative control, NC), the positive control diet (PC) supplemented with 1445 mg zinc/kg zinc oxide in the basal diet, and the H. illucens larval meal complete replacement of fishmeal in the basal diet (HILM), for 28 days in ETEC-challenged pig housing. The results showed that the relative transcript abundances of ZO-1, pBD2, PR39, and PG1–5 were increased (p < 0.05) in pigs fed the HILM diet compared with those fed the NC diet. In addition, the HILM diet reduced (p < 0.05) the serum contents of IL-8 and increased (p < 0.05) the serum contents of IL-10 and IgG compared with the NC diet. In terms of the molecular mechanisms by which immune homeostasis is improved, the p-NF-κB/ NF-κB ratio and TLR2 protein expression in the colon were decreased (p < 0.05) in pigs fed the HILM diet compared with those fed the NC diet. Compared with the NC diet, the HILM diet reduced (p < 0.05) the protein expression of HDAC3 and HDAC7 in the colon of pigs. The SIRT1, acH3K9, and pH3S10 protein expressions in the colon were the greatest (p < 0.05) in pigs fed the HILM diet compared with the NC diet. HILM diets improved the colonic immune homeostasis in weaned piglets by enhancing the antimicrobial peptide expression, thereby mitigating ETEC challenges in pig housing. Mechanistically, HILM diets promote antimicrobial peptide expression through increased histone acetylation (acH3K9 and pH3S10). Full article

Atopic dermatitis (AD) is a chronic inflammatory skin disease in which barrier impairment, immune dysregulation, and gut–skin dysbiosis intersect, prompting growing interest in probiotics as microbiota-modulating adjuncts. We conducted a narrative review of peer-reviewed articles indexed in PubMed, Scopus, and Google Scholar, restricted to publications from 1 January 2018 to 31 October 2025 (searches last run in December 2025). Eligible evidence included randomized controlled trials (RCTs), observational studies, and mechanistic or conceptual reviews addressing microbiome alterations and microbiota-modulating interventions in AD. Most pediatric RCTs using multistrain, Lactobacillus-dominant formulations (often combined with Bifidobacterium) reported modest improvements in AD severity and pruritus and in selected barrier- and inflammation-related biomarkers. However, direct cutaneous microbiome “restoration” outcomes were reported in a minority of studies, and most clinical evidence relies on clinical endpoints and gut–skin axis plausibility rather than longitudinal skin microbiome readouts. Single-strain regimens showed inconsistent effects, and evidence in adolescents and adults remained heterogeneous. Mechanistically, probiotics may enhance short-chain fatty acid (SCFA) signaling, dampen toll-like receptor 2/4 (TLR2/4)-nuclear factor kappa B (NF-κB) activation, and promote interleukin-10 (IL-10)- and transforming growth factor-β (TGF-β)-driven tolerance. Probiotics are a biologically plausible adjunct targeting the gut–skin axis in AD and are generally well tolerated; however, heterogeneity across trials, limited follow-up, inconsistent adverse-event reporting, and scarce skin microbiome endpoints preclude firm clinical recommendations. Full article

Kidney fibrosis represents the final common pathway of nearly all progressive renal diseases, linking acute kidney injury (AKI) and chronic kidney disease (CKD) through a maladaptive repair process. Regardless of etiology, persistent inflammation and excessive extracellular matrix (ECM) deposition drive irreversible structural distortion and functional decline in the kidney. Among cellular mediators, macrophages occupy a central role across the continuum from acute injury to fibrosis, orchestrating both tissue injury and repair through dynamic transitions between pro-inflammatory (M1) and pro-fibrotic (M2) states in response to local cues. Here, we synthesize macrophage-driven mechanisms of renal fibrosis, emphasizing recruitment, infiltration, and local proliferation mediated by chemokine–receptor networks and mechanosensitive ion channels. In addition, in this review paper, we provide an overview on the dual roles of macrophages in acute inflammation and chronic remodeling through key cytokine signaling pathways (TLR4/NF-κB, IL-4/STAT6, TGF-β/Smad, IL-10/STAT3), highlighting how metabolic reprogramming, mechanochemical feedback via Yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding motif (TAZ) signaling, and epigenetic modulators collectively stabilize the fibrotic macrophage phenotype. Also, emerging insights into mitochondrial dysfunction, succinate–succinate receptor 1 (SUCNR1) signaling, and autophagy dysregulation reveal the metabolic basis of macrophage persistence in fibrotic kidneys. Understanding these multilayered regulatory circuits offers a framework for therapeutic strategies that selectively target macrophage-dependent fibrogenesis to halt the transition from acute injury to chronic renal failure. Full article

Background/Objectives: Doxorubicin (DOX) is a highly effective chemotherapeutic agent whose clinical use is limited by dose-dependent cardiotoxicity. This study aimed to investigate the potential protective effects of menthol against doxorubicin-induced cardiotoxicity (DIC) in a rat model. Methods: Forty rats were arbitrarily allocated into four groups: (1) normal control, (2) DOX-treated, (3) DOX + menthol treatment, and (4) menthol-only treatment. DOX (15 mg/kg) was applied intraperitoneally, and menthol (100 mg/kg) was applied orally for 7 days following the DOX injection. Cardiac tissue specimens and sera were collected for biochemical assays, histopathological analysis, and immunohistochemistry. Biomarkers of oxidative stress (MDA, GSH), inflammatory pathways (TLR4, MAPK, NF-κB, SREBP-1C), and apoptotic markers (P53, caspase-3) were assessed. Results: DOX employment caused remarkable rise in serum troponin levels (6.53 ± 0.98, p < 0.05), oxidative stress markers, and inflammatory proteins, alongside histopathological damage in cardiac tissues. Menthol treatment significantly suppressed oxidative stress (MDA, GSH), inflammation (TLR4, MAPK, NF-κB, SREBP-1C levels), and attenuated apoptosis (P53 and caspase-3 expression) (p < 0.05). Conclusions: Menthol may serve as a promising adjunctive therapy to reduce DOX cardiotoxicity without compromising DOX’s anticancer efficacy. Full article