Search Results (814)

Background/Objective: Sepsis-associated acute kidney injury (SA-AKI) is a substantial contributor to mortality in critically ill patients. This study aimed to investigate the impact of gum acacia (GA) and dexamethasone (DEX) combination on lipopolysaccharide (LPS)-induced SA-AKI in rats. Methods: Thirty-six male Sprague Dawley rats were separated into six groups, including the control, GA group, LPS-induced AKI group, DEX + LPS group, GA + LPS group, and GA + DEX + LPS group. AKI was induced in rats using LPS (10 mg/kg, i.p.). GA was administered orally (7.5 g/kg) for 14 days before LPS injection, and DEX was injected (1 mg/kg, i.p.) 2 h after LPS injection. Results: LPS injection significantly (p < 0.05, vs. control group) impaired renal function, as evidenced through increased levels of kidney function biomarkers, decreased creatinine clearance, and histopathological alterations in the kidneys. LPS also significantly (p < 0.05, vs. control group) elevated levels of oxidative stress markers, while it reduced levels of antioxidant enzymes. Furthermore, LPS triggered an inflammatory response, manifested by significant (p < 0.05, vs. control group) upregulation of Toll-like receptor 4, myeloid differentiation primary response 88, interleukin-1β, tumor necrosis factor-α, and nuclear factor-κB, along with increased expression of high-mobility group box 1. Administration of GA significantly ameliorated LPS-induced renal impairment by enhancing antioxidant defenses and suppressing inflammatory pathways (p < 0.05, vs. LPS group). Furthermore, GA-DEX-treated rats showed improved kidney function, reduced oxidative stress, and attenuated inflammatory markers (p < 0.05, vs. LPS group). Conclusions: The GA-DEX combination exhibited potent renoprotective effects against LPS-induced SA-AKI, possibly due to their antioxidant and anti-inflammatory properties. These results suggest that the GA-DEX combination could be a promising and effective therapeutic agent for managing SA-AKI. Full article

Lipopolysaccharide (LPS), the defining outer membrane component of Gram-negative bacteria, is a potent immunostimulant recognized by Toll-like receptor 4 (TLR4). While extensively studied for its roles in immune activation and barrier disruption, the potential function of LPS as a developmental cue remains largely unexplored. By leveraging Caenorhabditis elegans and its genetic and gnotobiotic advantages, we screened a panel of Escherichia coli LPS biosynthesis mutants. This screen revealed that the loss of outer core glycosylation in the ∆rfaG mutant causes significant developmental delay independent of bacterial metabolism. Animals exhibited developmental delay that was rescued by exogenous LPS or amino acid supplementation, implicating that LPS triggers nutrient-sensing signaling. Mechanistically, this developmental arrest was mediated by the host FOXO transcription factor DAF-16, which is the key effector of insulin/IGF-1 signaling (IIS). Our findings uncover an unprecedented role for microbial LPS as a critical regulator of host development, mediated through conserved host IIS pathways, fundamentally expanding our understanding of host–microbe crosstalk. Full article

Acute hepatopancreatic necrosis disease (AHPND), caused by the bacterium Vibrio parahaemolyticus, is a major threat to global shrimp aquaculture. In this study, we evaluated the therapeutic effects of phage therapy in Litopenaeus vannamei challenged with AHPND-causing Vibrio parahaemolyticus. Phage application at various concentrations significantly improved shrimp survival, with the 1 ppm group demonstrating the highest survival rate. Enzymatic assays revealed that phage-treated shrimp exhibited enhanced immune enzyme activities, including acid phosphatase (ACP), alkaline phosphatase (AKP), and lysozyme (LZM). In addition, antioxidant defenses such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX), and total antioxidant capacity (T-AOC) significantly improved, accompanied by reduced malondialdehyde (MDA) levels. Serum biochemical analyses demonstrated marked improvements in lipid metabolism, particularly reductions in triglyceride (TG), total cholesterol (TC), and low-density lipoprotein (LDL), alongside higher levels of beneficial high-density lipoprotein (HDL). Transcriptomic analysis identified 2274 differentially expressed genes (DEGs), notably enriched in pathways involving fatty acid metabolism, peroxisome functions, lysosomes, and Toll-like receptor (TLR) signaling. Specifically, phage treatment upregulated immune and metabolic regulatory genes, including Toll-like receptor 4 (TLR4), myeloid differentiation primary response protein 88 (MYD88), interleukin-1β (IL-1β), nuclear factor erythroid 2-related factor 2 (Nrf2), and peroxisome proliferator-activated receptor (PPAR), indicating activation of innate immunity and antioxidant defense pathways. These findings suggest that phage therapy induces protective immunometabolic adaptations beyond its direct antibacterial effects, thereby providing an ecologically sustainable alternative to antibiotics for managing bacterial diseases in shrimp aquaculture. Full article

Background/Objectives: The incidence and prevalence of ischemic stroke, a leading cause of death and disability worldwide, are significantly higher in older adults than in younger individuals. Senescence induces a variety of biological changes that influence the pathogenesis of diseases such as ischemic stroke, thereby necessitating age-specific medical treatments. However, the molecular mechanisms underlying age-related differences in ischemic stroke progression remain poorly understood. Methods: We compared the histological and molecular features of ischemic stroke in a photothrombotic mouse model, focusing on 9-week-old (young) and 90-week-old (old) mice. Results: We found that microglial accumulation at the infarct region of the cerebral cortex was significantly lower in old mice than in young ones. This reduction in the microglial response was accompanied by a decrease in the morphological robustness of the astrocytes forming the glial scar. Furthermore, the mRNA expression of proinflammatory cytokines CXCL10, CCL2, and TNF-α, which were upregulated in the infarct region, was considerably higher in the old mice than in the young ones. Cytokine expression was well correlated with the mRNA levels of Toll-like receptor 4 (TLR4), a key regulator of neuroinflammation in old mice, but less correlated with them in young mice. Interestingly, Tlr4 mRNA expression in young mice was negatively correlated with the mRNA expression of the epigenetic regulator HDAC7, whereas this correlation was positive in old mice. Conclusions: These findings suggest that age-dependent changes in epigenetic regulation, such as the interaction between HDAC7 and TLR4, may contribute to the distinct pathological progression of ischemic stroke in older individuals. Full article

Background/Objectives: Atractylodes lancea (Thunb.) DC. [Asteraceae] (ALR)-derived exosome-like nanoparticles (ALR-ELNs) exhibit anti-neuroinflammatory effects in microglial cells. However, the associated mechanisms and pathways are unknown. We aimed to characterize the effects of ALR-ELNs on inflammatory responses of BV-2 microglial cells to lipopolysaccharide (LPS) using RNA sequencing. Methods: ALR-ELNs were fractionated from ALR. BV-2 microglial murine cells were stimulated with LPS after treatment with ALR-ELNs. RNA sequencing was performed to analyze variations in mRNA levels. Ingenuity pathway analysis (IPA) was performed to investigate the mechanism of action of ALR-ELNs. mRNA expression was assessed using real-time quantitative polymerase chain reaction (qPCR). Results: The expression of 651 genes was downregulated, whereas that of 1204 genes was upregulated in LPS-stimulated BV2 cells pretreated with ALR-ELNs. The IPA showed that the effects of ALR-ELNs on inflammation took place through pathogen-influenced signaling. Network analysis via IPA showed that the Toll-like receptor (TLR) is involved in the suppression of inflammation by ALR-ELNs. The qPCR analysis showed that pretreatment with ALR-ELNs significantly reduced TLR4 mRNA expression. Conclusions: ALR-ELNs suppress the release of inflammatory mediators by downregulating TLR4 expression, which is a novel mechanism by which ALR-ELNs act on microglia. Identifying active ingredients in ALR-ELNs that downregulate TLR4 expression can advance the development of therapeutic drugs for neuroinflammatory diseases. Full article

There is a present need to develop alternative biotherapeutic drugs to mitigate the exacerbated inflammatory immune responses characteristic of sepsis. The potent endotoxin lipopolysaccharide (LPS), a major component of Gram-negative bacterial outer membrane, activates the immune system via Toll-like receptor 4 (TLR4), triggering macrophages and a persistent cascade of inflammatory mediators. Our previous studies have demonstrated that Fh15, a recombinant member of the Fasciola hepatica fatty acid binding protein family, can significantly increase the survival rate by suppressing many inflammatory mediators induced by LPS in a septic shock mouse model. Although Fh15 has been proposed as a TLR4 antagonist, the specific mechanisms underlying its immunomodulatory effect remained unclear. In the present study, we employed a quantitative proteomics approach using tandem mass tag (TMT) followed by LC-MS/MS analysis to identify and quantify differentially expressed proteins that participate in signaling pathways downstream TLR4 of macrophages, which can be dysregulated by Fh15. Data are available via ProteomeXchange with identifier PXD065520. Based on significant fold change (FC) cut-off of 1.5 and p-value ≤ 0.05 criteria, we focused our attention to 114 proteins that were upregulated by LPS and downregulated by Fh15. From these proteins, TNFα, IL-1α, Lck, NOS2, SOD2 and CD36 were selected for validation by Western blot on murine bone marrow-derived macrophages due to their relevant roles in the NF-κB, iNOS, oxidative stress, and phagosome signaling pathways, which are closely associated with sepsis pathogenesis. These results suggest that Fh15 exerts a broad spectrum of action by simultaneously targeting multiple downstream pathways activated by TLR4, thereby modulating various aspects of the inflammatory responses during sepsis. Full article

Neurotrophins and inflammatory mediators are known to influence endometrial function, but their interplay in luminal epithelial cells remains poorly characterized. In this study, sheep endometrial luminal epithelial cells (SELECs) were treated with nerve growth factor (NGF), lipopolysaccharide (LPS), or both, and the effects on gene expression and prostaglandin secretion were evaluated. NGF stimulation alone induced a clear transcriptional activation of NGF, neurotrophic receptor tyrosine kinase 1 (NTRK1), p75 neurotrophin receptor (p75NTR), cyclooxygenase 2 (COX2), and steroidogenic acute regulatory protein (STAR). LPS treatment selectively increased Toll-like receptor 4 (TLR4), COX2, and insulin-like growth factor binding protein 6 (IGFBP6). Combined NGF and LPS treatment did not enhance the transcriptional response beyond that induced by NGF alone, except for STAR. However, co-treatment resulted in a modest increase in prostaglandin production, particularly prostaglandin F2α (PGF2α), but not prostaglandin E2 (PGE2), compared to single treatments, suggesting a possible post-transcriptional modulation rather than a transcriptional synergy. These findings indicate that NGF acts as the primary transcriptional driver in SELECs, while LPS contributes selectively and may enhance prostaglandin output. The observed increase in prostaglandin production may involve post-transcriptional mechanisms, although this remains to be confirmed. Full article

In our previous studies, methylated CpG oligodeoxynucleotides (ODN) derived from Bifidobacterium longum subsp. infantis have demonstrated immunomodulatory effects through the induction of regulatory T cells (Tregs). To define the structural determinants underlying this effect, we synthesized four CpG ODNs varying in methylation degree, CpG motif placement, and backbone length. These include (1) ODN-A (2m-V1), a 20-nucleotide CpG oligodeoxynucleotide incorporating two 5-methylcytosines at positions 4 and 12 within centrally placed CpG motifs; (2) ODN-B (um-V2), a 20-nucleotide CpG oligodeoxynucleotide with a backbone structure identical to ODN-A but unmethylated; (3) ODN-C (2m’-V3), a 20-nucleotide CpG oligodeoxynucleotide with a backbone structure identical to ODN-A, but with two 5-methylcytosines shifted to positions 7 and 15; (4) ODN-D (3m-V4), a 27-nucleotide CpG oligodeoxynucleotide with an extended backbone structure, this time with three 5-methylcytosines at positions 3, 11, and 19. Using a murine model of an OVA-induced allergy, we show that methylated ODN-A (2m-V1) and ODN-D (3m-V4) markedly reduce serum anti-OVA IgE, clinical symptoms, eosinophilic infiltration, and Th2/Th17 responses, while promoting splenic Treg expansion and IL-10 production. In contrast, unmethylated ODN-B (um-V2) and a positionally altered methylated ODN-C (2m’-V3) both failed to suppress allergic inflammation, and, in contrast, enhanced the Th2/Th17 response and induced robust in vitro Toll-like receptors TLR7/8/9 expression in native splenocytes. These findings suggest that both methylation and motif architecture critically influence the immunologic profile of CpG ODNs. Our results provide mechanistic insights into CpG ODN structure/function relationships and support the therapeutic potential of select methylated sequences for restoring immune tolerance in allergic diseases. Full article

Metabolic dysfunction-associated steatohepatitis (MASH) is a progressive liver disease linked to fibrosis and hepatocellular carcinoma (HCC). Gut-derived lipopolysaccharide (LPS) promotes hepatic inflammation, fibrosis, and angiogenesis through toll-like receptor 4 (TLR4) signaling. This study examined the effects of rifaximin, a non-absorbable, gut-targeted antibiotic, on MASH-related liver fibrosis and early hepatocarcinogenesis, with a focus on the LPS–epiregulin–IL-8–angiogenesis axis.MASH was induced in Fischer 344 rats using a choline-deficient, L-amino acid-defined high-fat diet (CDAHFD). Rifaximin (30 mg/kg/day) was orally administered for 12 weeks. Liver histology, gene expression, intestinal permeability, LPS levels, and angiogenic markers were evaluated. Rifaximin reduced hepatic inflammation, fibrosis, hydroxyproline content, and fibrogenic gene expression. The number and size of GST-P-positive preneoplastic lesions and proliferation-related genes were decreased. Portal LPS levels and Kupffer cell activation declined, with downregulation of Lbp, Cd14, Tlr4, and inflammatory cytokines. Rifaximin decreased hepatic epiregulin and IL-8 expression, attenuated CD34-positive neovascularization, and suppressed proangiogenic gene expression, accompanied by improved intestinal barrier function and reduced gut permeability. Rifaximin mitigates MASH progression by restoring gut barrier integrity, limiting LPS translocation, and inhibiting fibrogenic and angiogenic pathways. These results suggest its potential as a chemopreventive agent in MASH-related hepatocarcinogenesis. Full article

Stroke represents a significant public health burden, ranking as a leading cause of death and disability globally. The prevalence of stroke increases with age, with ischemic stroke accounting for nearly 87% of cases globally. The pathophysiology of stroke is characterized by neuronal injury, neuroinflammation, and oxidative stress, which exacerbate brain damage and hinder recovery. Myeloid Differentiation Factor 2 (MD2), an accessory protein of Toll-like receptor 4 (TLR4), has emerged as a key player in mediating inflammatory responses in stroke. This short review discusses the molecular mechanisms by which MD2 contributes to neuroinflammation and neuronal death following stroke and highlights MD2 as a promising therapeutic target for stroke treatment. Subsequently, we investigate the potential of MD2 inhibitors, their underlying mechanisms, and the therapeutic prospects of such inhibitors in reducing stroke-induced brain damage. Full article

Background: Alpha-1 antitrypsin (AAT) is a multifunctional protease inhibitor that has been shown to have anti-inflammatory properties in various diseases. AAT has been reported to protect against renal injury via anti-apoptotic, anti-fibrotic, and anti-inflammatory effects. However, its role in mitigating renal inflammation and reducing high blood pressure induced by salt-loading has never been studied. Methods: In this study, we salt-loaded 129Sv mice to induce hypertension and then administered purified human AAT (hAAT) or the vehicle to investigate whether renal inflammation and associated inflammatory/signaling pathways are mitigated. Results: Western blotting and densitometric analysis showed administration of hAAT attenuated protein expression of kidney injury molecule-1 (KIM1), CD93, CD36, and the toll-like receptor 2 and 4 (TLR-2/4) in kidney lysates. Similarly, protein expression of two key inflammatory transcription factors, signal transducer and activator of transcription 3 (STAT3) and NF-Kappa B were shown to be attenuated in the kidneys of 129Sv mice that received hAAT. Conversely, hAAT treatment upregulated the expression of heat shock protein 70 (HSP70) and immunohistochemistry confirmed these findings. Conclusions: Purified hAAT administration may be efficacious in mitigating renal inflammation associated with the development of hypertension from salt-loading, potentially through a mechanism involving the reduction of pro-inflammatory and injury-associated proteins. Full article

Background/Objectives: Inflammatory breast carcinoma (IBC) is an aggressive and rare neoplasm, accounting for 1–5% of all breast cancers. Toll-like receptor type 4 (TLR4) and Advanced Glycation End Products Receptor (AGER/RAGE) have been implicated in breast cancer, and have been shown to promote tumor growth, metastasis, and resistance to therapy by modulating the tumor microenvironment and inflammatory pathways. However, the role of TLR4 and AGER in IBC has not been elucidated. Methods: TLR4 and AGER immunofluorescence expression were evaluated in 27 IBC and 24 non-IBC samples. The expression data and clinicopathological parameters, including the prognostic values of these biomarkers, were compared. TLR4 and AGER gene expression were investigated using the microarray transcriptomic dataset of IBC and non-IBC samples (Gene Expression Omnibus repository—GEO). Results: IBC samples showed higher TLR4 and AGER immunoexpression than the non-IBC group and were associated with obesity and Ki-67 expression (p < 0.05). AGER expression in IBC versus non-IBC was also statistically associated with triple-negative molecular subtypes. Non-IBC subjects with AGER immunoexpression above the cutoff (106.1%, sensitivity of 92.3%, and specificity of 56.2%) showed reduced metastasis-free survival (p = 0.032). In the multivariate analysis, high TLR4 immunostaining increased the risk of metastasis-free survival by 1.029-fold. Analyzing three external GEO datasets confirmed that TLR4 and AGER expression increased in IBC compared to non-IBC samples. Conclusions: Overall, IBC samples showed higher TLR4 and AGER expressions than other breast cancer types, shedding light on the significance of these markers on IBC biology. Full article

Background/Objectives: Acute lung injury (ALI) is an inflammatory condition characterized by tissue barrier damage, which leads to vascular leakage, pulmonary edema, and compromised gas exchange. Lipopolysaccharides (LPS) are a component of Gram-negative bacteria, which trigger inflammation by Toll-like receptor 4 (TLR4) activation. Herein, we investigated the possibility that Pasireotide (PAS) exerts protective effects in an experimental model of ALI. Methods: C57BL/6 male mice received an intratracheal injection of saline or LPS, followed by PAS or vehicle treatment. Bronchoalveolar lavage fluid (BALF) was collected via tracheal catheterization, and Western blot analysis was used to detect protein expression variations. Results: Our results suggest that PAS treatment alleviates LPS-induced mouse lung injury and inflammation. JAK/STAT and MAPK activation levels in the inflamed lungs were suppressed due to PAS treatment, as well as BALF protein concentration. Additionally, PAS counteracted LPS-induced Grp94 protein reduction, suggesting the involvement of ATF6 in PAS-triggered barrier-protective effects. Grp94 is a downstream ATF6 target. Conclusions: Our data demonstrate that PAS protects mouse lungs against LPS in an experimental model of ALI. Full article

Foodborne trematode infections are recognized as a significant risk factor for cholangiocarcinoma (CCA) in endemic regions. Infection with the liver fluke Opisthorchis felineus induces precursor lesions of CCA, including the biliary intraepithelial neoplasia. The mechanisms underlying liver-fluke-associated neoplasia remain poorly understood. This study aims to identify the role of EGFR and Toll-like receptor 4-associated signaling pathways in bile duct epithelial neoplasia linked to liver fluke infection in patients, animal models, and cell models. Elevated levels of EGFR and phosphorylated EGFR were observed in the bile duct epithelium of patients with cholangiocarcinoma, as well as in the bile duct epithelium of laboratory hamsters. The EGFR content correlated with the degree of bile duct epithelial neoplasia. Additionally, a significant increase in the cell proliferation and migration rates of human H69 cholangiocytes was found, whereas those of HepG2 hepatoma cells remained unaffected following the helminth excretory–secretory product (ESP) treatment. An EGFR inhibitor eliminated the enhanced cell proliferation (p = 0.005) and migration (p = 0.001) rates. Similar outcomes were achieved using Marimastat, an inhibitor of TLR-4-associated metalloproteinases. Thus, our study unveils novel avenues for exploring the mechanisms of helminth-associated carcinogenesis and for identifying key components of ESPs that mediate their mitogenic effects. Full article

Recurrent bacterial cystitis in women can lead to interstitial cystitis or bladder pain syndrome (IC/BPS). Activation of Toll-like receptor 4 (TLR4) by LPS can upregulate signaling of the pro-inflammatory receptor p75^NTR. The aim of the presented study was to assess whether p75^NTR antagonist THX-B can modulate LPS-mediated inflammation in bladder cells. In vitro expression and LPS-activation of p75^NTR were confirmed in urothelial (URO) and smooth muscle (SMC) cells. In UROs, p75^NTR antagonism abolished the LPS-elicited rise in membrane-bound and soluble TNF-α. However, it could not prevent LPS-induced rise in phosphorylated ERK nor decrease in phosphorylated p38MAPK, nor the increase in iNOS and nitric oxide (NO) content. On the other hand, in SMCs, LPS increased phosphorylation of JNK, nuclear translocation of NF-κB, and association of TRAF6 to p75^NTR, outcomes prevented by p75^NTR antagonism. In UROs, LPS decreased the expression of tight junction proteins, ZO-1 and occludin, with the latter rescued by p75^NTR antagonism. Intraurethral instillation of LPS increased inflammation in the lamina propria, activation of JNK, and contractile activity of bladder tissue. Alternatively, intraperitoneal THX-B injections prevented LPS-induced inflammation but not enhanced muscle contraction. Our results suggest that inhibition of p75^NTR could help in reducing bladder symptoms during cystitis. Full article