TLR4 Signaling Pathway Research Articles

Shrimp White Spot Viral Infections Are Attenuated by Organic Acids by Regulating the Expression of HO-1 Oxygenase and β-1,3-Glucan-Binding Protein

The absence of efficient on-farm interventions against white spot syndrome viral (WSSV) infections can cause significant economic losses to shrimp farmers. With this exploratory study we aimed to test, both in vitro and in vivo, the efficacy of an organic acid mixture (Aq) against WSSV infections in shrimp. In vitro, using shrimp gut primary cells (SGP), 2% Aq significantly reduced WSSV infection and the amounts of H2O2 released but had no impact on CAT and SOD expression. In vivo, in a shrimp challenge test, 2% Aq significantly downregulated the expression of proteins involved in WSSV virulence, such as the lipopolysaccharide-β-1,3-glucan-binding protein (LGBP) and the TLR signalling pathway (LvECSIT), and increased the expression of HO-1 oxygenase. Additionally, at 2% Aq, the expression of the digestive-related enzyme carboxypeptidase B was upregulated in the gut, alongside a significant decrease in IL-22 expression, a cytokine usually increased during WSSV infection in shrimp. A low mortality rate (7.33%) was recorded in infected shrimp treated with 2% Aq compared to the 96.66% mortality in the absence of Aq. The peritrophic membrane (PM) was proven essential to ensure Aq efficacy, as the infected and treated PM deficient shrimp (PM−) had a mortality rate of 27.8%, compared to only 9.34% mortality in the infected shrimp at 2% Aq and in the presence of PM (PM+). Aq significantly increased the expression of mucin-1, mucin-2, mucin-5AC, mucin-5B, and mucin-19 in both PM+ and PM− shrimp. Conclusively, organic acid in mixtures can protect farmed shrimp against WSSV infection and increase their survivability through a mediated gut health effect which includes resistance to oxidative stress and improved immunity.

In Silico-Guided Discovery of Polysaccharide Derivatives as Adjuvants in Nanoparticle Vaccines for Cancer Immunotherapy.

Cancer vaccines utilizing nanoparticle (NP) structures that integrate antigens and adjuvants to enhance delivery and stimulate immune responses are emerging as a promising avenue in cancer immunotherapy. However, the development of cancer vaccines has been significantly hindered by the low immunogenicity of tumor antigens. To address this challenge, substantial efforts have been made in developing innovative adjuvants to elicit effective immune responses. In this study, we develop a NP cancer vaccine assisted by a polysaccharide derivative adjuvant, designed through a computational strategy, to evoke effective antigen-specific antitumor immunity. Using TLR4 as the putative receptor, we conducted a comprehensive evaluation of a prescreening library consisting of 34 inulin derivatives through docking and molecular dynamics simulation. Consequently, a new derivative, benzoylated inulin (InBz), is selected as the most promising TLR4 agonist. The adjuvant effect of InBz is evaluated by fabricating InBz NPs encapsulating the model antigen ovalbumin (OVA). In vitro, InBz-OVA NPs effectively activate the TLR4 signaling pathways and facilitate dendritic cell maturation, thereby enhancing the antigen delivery and presentation. In vivo, InBz-OVA NPs outperform a commercial aluminum-based adjuvant, elicit robust antibody titers, induce antigen-specific cytotoxic T lymphocytes, and achieve significant tumor suppression in murine models. Besides, the adjuvant effects of other representative derivatives, namely, acetylated and chloroacetylated inulin, with moderate and low potential from the library, are also chemically synthesized and experimentally evaluated and found to be in agreement with computational predictions, confirming the credibility of the strategy. This study provides an effective platform for the pursuit of efficient polysaccharide-based vaccine adjuvants.

Dietary supplementation with milk‐derived Bifidobacterium animalis subsp. lactis relieves colitis‐linked reproductive disorders via gut‐testis axis

AbstractRapid urbanization, medication, and modern dietary patterns are the main challenges leading to impaired fertility, with a lack of effective therapies. Emerging evidence suggests that reproductive disorders may be closely associated with intestinal damage or occasionally worsen by the side effects of medications. Therefore, the development of dietary supplements as alternatives is crucial for intestinal‐linked reproductive health. Milk and dairy products are essential in dietary nutrition with great potential functional ingredients. Bifidobacterium animalis subsp. lactis NJ241 (NJ241), a promising probiotic isolated from naturally fermented bovine milk, remains underexplored. This study aims to investigate the molecular mechanisms of NJ241 on colitis and its associated reproductive disorders. The biomarker microbes and their correlated metabolites were further explored by 16S rRNA sequencing and metabolomics. Hematological analysis and histopathological examination were applied for conjoined identification. Results indicated that NJ241 effectively restored the expression levels of Claudin‐2 and MLCK1, reducing intestinal permeability. Multi‐omics results further revealed that NJ241 may effectively improve gut barrier integrity by increasing the abundance of Akkermansia muciniphila and its metabolite trans‐ferulic acid. This effect was accompanied by a reduction in the pro‐inflammatory cytokine IL‐6 in both serum and testicular tissue, mediated through the TLR4 signaling pathway. Consequently, the restoration of microbiota homeostasis and a systemic reduction in inflammation rescued testicular spermatogenesis, which was impaired by colitis. The current findings consistently elucidated the potential molecular mechanism by which NJ241 ameliorates colitis‐linked reproductive disorders through the gut‐testis axis. Additionally, NJ241 demonstrates promise as a probiotic supplement for the development of fortified dairy products and provides strong evidence for the potential reproductive health benefits of naturally fermented bovine milk.

The Inhibitory Effects of Alpha 1 Antitrypsin on Endosomal TLR Signaling Pathways

Endosomal toll-like receptors (TLRs) TLR7, TLR8, and TLR9 play an important role in systemic lupus erythematosus (SLE) pathogenesis. The proteolytic processing of these receptors in the endolysosome is required for signaling in response to DNA and single-stranded RNA, respectively. Targeting this proteolytic processing may represent a novel strategy to inhibit TLR-mediated pathogenesis. Human alpha 1 antitrypsin (hAAT) is a protease inhibitor with anti-inflammatory and immunoregulatory properties. However, the effect of hAAT on endosomal TLRs remains elusive. In this study, we first tested the effect of hAAT on TLR9 signaling in dendritic cells (DCs). We showed that hAAT inhibited TLR9-mediated DC activation and cytokine production. Human AAT also lowered the expressions of interferon signature genes. Western blot analysis showed that hAAT reduced the expression of the active form (cleaved) of TLR9 in DCs, indicating a novel mechanism of hAAT function in the immune system. We next tested the effect of hAAT on TLR7/8 signaling. Similar to the effect on TLR9 signaling, hAAT also inhibited R848 (TLR7 and 8 agonist)-induced DC activation and functions and lowered the expressions of interferon signature genes. Our in vivo studies using hAAT transgenic mice also showed that hAAT attenuated R848-induced pathogenesis. Specifically, hAAT completely blocked the R848 induction of germinal center T cells (GC T), B cells (GC B), and plasma cells (GC PCs), as well as T follicular T helper cells (TFH), which are all critical in lupus development. These data demonstrated that hAAT inhibited TLR7/8 and TLR9 signaling pathways, which are critical for lupus development. These findings not only advanced the current knowledge of hAAT biology, but also implied an insight into the clinical application of hAAT.

Network Pharmacology Suggests Mechanisms for Therapeutic Effects of Caulis Sinomenii on Avian Gout.

Avian gout (AG) is detrimental to the survival and production performance of poultry and effective drugs are lacking. Caulis sinomenii has shown clinical efficacy against arthritis and may have potential value in AG prevention and treatment. In the present study, the components and targets of C. sinomenii and AG-related targets were identified using relevant databases. The common targets, target interactions, and signaling pathways involved in the prevention and treatment of AG by C. sinomenii were determined using software to explore the potential mechanisms of action. Sixteen components of C. sinomenii, eight of which were active ingredients with 351 targets and 2993 AG-related targets, were identified using several databases. A total of 156 common targets were associated with 202 biological processes and 34 pathways. Toll-like receptor 4 (TLR4) and prostaglandin endoperoxide synthase 2 were core targets. These targets may exert therapeutic effects on AG through four pathways: the nucleotide-binding oligomerization domain (NOD)-like receptor, mammalian target of rapamycin, TLR, and mitogen-activated protein kinase signaling pathways. In summary, C. sinomenii has potential therapeutic efficacy against AG through multicomponent, multi-target, and multi-pathway mechanisms.

Polysaccharides isolated from Ampelopsis grossedentata and their immunomodulatory activity.

To explore the immunomodulatory activity of polysaccharides from Ampelopsis grossedentata, two polysaccharides named AGP1 and AGP2 were isolated and purified by DEAE-cellulose 52 column and Sephacryl S-300HR chromatography. AGP1 and AGP2 were composed of fucose, arabinose, rhamnose, galactose, glucose, mannose, galacturonic acid, and glucuronic acid, with a ratio of 0.5: 10.2: 0.9: 31.8: 7.4: 3.4: 21.6: 24.2 and 0.4: 6.0: 0.5: 23.3: 3.3: 6.2: 33.5: 26.8, respectively. The average molecular weights of AGP1 and AGP2 were found to be 6.60×105Da and 7.24×105Da, respectively. AGP1 contained →4,6)-Galp-(1→glycosidic linkages, while AGP2 contained →2)-Galp-(1→and →2,3,4)-Glcp-(1→glycosidic linkages. The structures of AGPs were characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, and scanning electron microscope. The immunomodulatory activity of AGPs was investigated in RAW264.7 cells, and the results indicated that AGPs significantly activated macrophages, promoted cells differentiation and NO secretion, increased the expression of IL-6 and TNF-α, and induced macrophage M1 polarization. Transcriptomic analysis indicated that AGP1 and AGP2 regulated a total of 1043 and 970 differentially expressed genes respectively, which were identified in different immune related signaling pathways. Moreover, the immunoblot demonstrated that AGPs exerted immune-promoting effects through the TLR4, MAPK and NF-κB signaling pathways in macrophages. Consequently, AGPs have potent immunomodulatory activity and can be considered as immunomodulators in medical and food industries.

A review of the role of bioactive components in legumes in the prevention and treatment of cardiovascular diseases.

Cardiovascular diseases (CVD) represent a primary global health challenge. Poor dietary choices and lifestyle factors significantly increase the risk of developing CVD. Legumes, recognized as functional foods, contain various bioactive components such as active peptides, protease inhibitors, saponins, isoflavones, lectins, phytates, and tannins. Studies have demonstrated that several of these compounds are associated with the prevention and treatment of cardiovascular diseases, notably active peptides, saponins, isoflavones, and tannins. This review aims to analyze and summarize the relationship between bioactive compounds in legumes and cardiovascular health. It elaborates on the mechanisms through which active ingredients in legumes interact with risk factors for cardiovascular diseases, such as hypertension, hypercholesterolemia, endothelial dysfunction, and atherosclerosis. These mechanisms include, but are not limited to, lowering blood pressure, regulating lipid levels, promoting anticoagulation, enhancing endothelial function, and modulating TLR4 and NF-κB signaling pathways. Together, these mechanisms emphasize the potential of legumes in improving cardiovascular health. Additionally, the limitations of bioactive components in legumes and their practical applications, with the goal of fostering further advancements in this area were discussed.

Gegen Qinlian Decoction Attenuates Colitis-Associated Colorectal Cancer via Suppressing TLR4 Signaling Pathway Based on Network Pharmacology and In Vivo/In Vitro Experimental Validation

Background: Gegen Qinlian Decoction (GQD), is used for intestinal disorders like ulcerative colitis, irritable bowel syndrome, and colorectal cancer. But the precise mechanisms underlying its anti-inflammatory and anti-tumor effects are not fully elucidated. Methods: Use network pharmacology to identify targets and pathways of GQD. In vivo (azoxymethane/dextran sodium sulfate (AOM/DSS)-induced colitis-associated colorectal cancer (CAC) mouse model) and in vitro (lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages) experiments were conducted to explore GQD’s anti-inflammatory and anti-tumor effects. We monitored mouse body weight and disease activity index (DAI), and evaluated colon cancer tissues using hematoxylin and eosin staining. Expression of Ki67 and F4/80 was determined by immunohistochemistry analysis. The protein levels of TLR4 signaling pathway were assessed by western blotting analysis. Enzyme-linked immunosorbent assay measured IL-1β, IL-6, and TNF-α levels. Immunofluorescence (IF) staining visualized NF-κB and IRF3 translocation. Results: There were 18, 9, 24 and 77 active ingredients in the four herbs of GQD, respectively, targeting 435, 156, 485 and 691 genes. Through data platform analysis, it was concluded that there were 1104 target genes of GQD and 2022 target genes of CAC. Moreover, there were 99 intersecting genes between GQD and CAC. The core targets of GQD contained NFKB1, IL1B, IL6, TLR4, and TNF, and GQD reduced inflammation by inhibiting the TLR4 signaling pathway. In vivo experiment, GQD increased mouse body weight, lowered DAI scores, while also alleviating histopathological changes in the colon and decreasing the expressions of Ki67 and F4/80 in the AOM/DSS-induced mice. GQD reduced IL-1β, IL-6, and TNF-α levels in the serum and downregulated TLR4, MyD88, and phosphorylation of IκBα, P65, and IRF3 in the colon tissue from AOM/DSS-induced mice. In vitro, GQD suppressed pro-inflammatory cytokines and TLR4 signaling pathway in the LPS-induced RAW264.7 cells, and combined with TAK242, it further reduced the phosphorylation of IκBα, P65. Conclusions: GQD mitigated CAC by inhibiting the TLR4 signaling pathway, offering a potential therapeutic approach for CAC management.

Musa paradisiaca L. Inflorescence Abrogates Neutrophil Activation by Downregulating TLR4/NF-KB Signaling Pathway in LPS-Induced Acute Lung Injury Model

Background/Objectives: Acute lung injury (ALI) is an inflammatory disorder affecting patients in intensive care with high mortality. No specific pharmacological treatment is available. Musa paradisiaca L. (banana) is a cosmopolitan plant, and homemade syrup from its inflorescence is used in many countries to treat pulmonary inflammation. Therefore, this study analyzed the hydroalcoholic extract (HEM) of the inflorescence on the ALI experimental model. Methods: Swiss mice were challenged with lipopolysaccharide and treated with HEM after 1, 24, and 48 h (five animals/group, three times). Results: The HEM-treated ALI mice presented a decrease in neutrophil migration in the bronchoalveolar lavage fluid (BALF), in the alveolar region, and in the blood, correlating to downregulation of CD18 expression. The HEM treatment also reduced the protein concentration in the BALF, caused lung edema formation, impaired NF-κB activation via inhibition of TLR4 signaling pathway, and decreased IL-1β, TNF-α production, free DNA release, and myeloperoxidase (MPO) activity. However, the extract induced an increased IL-10 in the BALF. Conclusions: Therefore, HEM’s anti-inflammatory and immunomodulatory activities in ALI mice are by deactivating neutrophils by decreasing CD18 receptor, free DNA release, and MPO activity and inducing IL-10 production. Thus, this study supports the use of banana inflorescence in folk medicine and suggests its rational use to develop a phytomedicine to treat pulmonary inflammation.

TLR4 Targeting: A Promising Therapeutic Approach Across Multiple Human Diseases.

TLR4 stands at the forefront of innate immune responses, recognizing various pathogen- associated molecular patterns and endogenous ligands, thus serving as a pivotal mediator in the immune system's defense against infections and tissue damage. Beyond its canonical role in infection, emerging evidence highlights TLR4's involvement in numerous non-infectious human diseases, ranging from metabolic disorders to neurodegenerative conditions and cancer. Targeting TLR4 signaling pathways presents a promising therapeutic approach with broad applicability across these diverse pathological states. In metabolic disorders such as obesity and diabetes, dysregulated TLR4 activation contributes to chronic low-grade inflammation and insulin resistance, driving disease progression. In cardiovascular diseases, TLR4 signaling promotes vascular inflammation and atherogenesis, implicating its potential as a therapeutic target to mitigate cardiovascular risk. Neurodegenerative disorders, including Alzheimer's and Parkinson's diseases, exhibit aberrant TLR4 activation linked to neuroinflammation and neuronal damage, suggesting TLR4 modulation as a strategy to attenuate neurodegeneration. Additionally, in cancer, TLR4 signaling within the tumor microenvironment promotes tumor progression, metastasis, and immune evasion, underscoring its relevance as a target for anticancer therapy. Advances in understanding TLR4 signaling cascades and their contributions to disease pathogenesis have spurred the development of various pharmacological agents targeting TLR4. These agents range from small molecule inhibitors to monoclonal antibodies, with some undergoing preclinical and clinical evaluations. Furthermore, strategies involving TLR4 modulation through dietary interventions and microbiota manipulation offer additional avenues for therapeutic exploration. Hence, targeting TLR4 holds significant promise as a therapeutic strategy across a spectrum of human diseases, offering the potential to modulate inflammation, restore immune homeostasis, and impede disease progression.

Berberine and Cyperus rotundus extract nanoformulations protect the rats against Staphylococcus-induced mastitis via antioxidant and anti-inflammatory activities: role of MAPK signaling.

Berberine (BER) and Cyperus rotundus rhizomes extract (CRE) are phytochemicals characterized by broad-spectrum pharmacological activity that could tackle the side effects of conventional mastitis therapies, however, they undergo a modest bioavailability. In the current study, nanoformulations of BER and CRE chitosan hydrogel (BER/CH-NPs, CRE/CH-NPs) were investigated for their antibacterial, antioxidant, anti-inflammatory and anti-apoptotic effects against S. aureus-induced mastitis in a rat model. The experiment was conducted on 80 early lactating female albino rats allocated into 6 groups; control, mastitis, BER/CH-NPs (1 and 0.5 mg), CRE/CH-NPs (0.5 and 0.25 mg), BER/CH-NPs + CRE/CH-NPs (0.5 + 0.25 and 0.25 + 0.125 mg). The nanoparticles were given by oral gavage once every other day from day 2 to day 12 after parturition. On the 13th day, intra-mammary inoculation with 100 µl of S. aureus suspension containing 2.1 × 108 CFU/ml in all groups except the control group. The results expressed the effect of BER/CH-NPs and CRE/CH-NPs on mammary gland tissue including significantly diminished viable bacterial load as well as attenuated the levels of MPO, MDA, caspase-3 with elevating Nrf2 level, and modulating glutathione redox. Also, the nanoformulations resulted in attenuation of the mRNA expression of TLR2, NOD2, Keap-1 and MAPK signaling pathway additional to the immune reactivity of NF-κB P65 and p-ERK as well as the preservation of the regular alveolar architecture. The supplementation of the berberine and Cyperus rotundus extract nanoformulations could be a prospective protective approach against Staphylococcal mastitis via their antibacterial, antioxidant, antiapoptotic, anti-inflammatory and modulation of MAPK signaling pathway.

Sparstolonin B potentiates the antitumor activity of nanovesicle-loaded drugs by suppressing the phagocytosis of macrophages in vivo

BackgroundExtracellular vesicles (EVs) and extruded nanovesicles (ENVs) are promising nanovesicles (NVs) for drug delivery. However, the application of these NVs is strongly hindered by their short half-life in the circulation. Macrophages (Mφs) in the liver and spleen contribute to the rapid depletion of NVs, but the underlying mechanism is unclear.MethodsBy collecting the supernatant of PANC-1 cells and squeezing PANC-1 cells, EVs and ENVs derived from PANC-1 cells were prepared via ultracentrifugation. NVs were subsequently identified via western blot, particle size measurement, and electron microscopy. The distribution of NVs in mouse bodies was observed with a live animal imaging system. Liver Mφs were extracted and isolated after NVs were administered, and transcriptome profiling was applied to determine differentially expressed genes (DEGs). siRNAs targeting interested genes were designed and synthesized. In vitro experiments, Mφs were transfected with siRNA or treated with the corresponding inhibitor, after which NV uptake was recorded. Doxorubicin (DOX) was encapsulated in ENVs using an ultrasound method. PANC-1 cell-derived tumors were established in nude mice in vivo, inhibitor pretreatment or no treatment was administered before intravenous injection of ENVs-DOX, and the therapeutic efficacy of ENVs-DOX was evaluated.ResultsNVs derived from PANC-1 cells were first prepared and identified. After intravenous injection, most NVs were engulfed by Mφs in the liver and spleen. Seven genes of interest were selected via transcriptome sequencing and validated via RT‒PCR. These results confirmed that the TLR2 signaling pathway is responsible for phagocytosis. siTLR2 and its inhibitor sparstolonin B (SpB) significantly inhibited the internalization of NVs by Mφs and downregulated the activity of the TLR2 pathway. The accumulation of ENVs-DOX in the liver was inhibited in vivo by pretreatment with SpB 40 min before intravenous injection, ultimately delaying tumor progression.ConclusionThe TLR2 pathway plays a crucial role in the sequestration of NVs by Mφs. A novel antiphagocytic strategy in which pretreatment of mice with SpB inhibits the clearance of NVs and prolongs their half-life in vivo, thereby improving delivery efficiency, was identified.Graphical

Potential role of Mappain, a prenylated stilbene, in reducing SARS-CoV-2 envelope protein-induced inflammation

As of right now, more than 776 million people have contracted the COVID-19-causing SARS-CoV-2 virus, which has also resulted in over 7 million deaths. A dysregulated host's innate immune response to the virus exacerbates clinical outcomes and leads to cytokine storm. Developing a drug targeting the multiple aspects of the SARS-CoV-2 virus-host cell interactions is essential for effective treatment. The 75 amino acid-long SARS-CoV-2 envelope (2E) protein is a small structural transmembrane protein that plays a crucial role in the viral life cycle and pathogenesis. Mappain is a plant-derived stilbene from Macaranga species that previously demonstrated antiviral potential against enteroviruses in tissue culture. This study aims to assess the inhibitory potential of Mappain against SARS-CoV-2 key proteins and induced hyperinflammation using computational and in-vitro approaches. Autodock Vina was used to evaluate mappain interaction with SARS- CoV-2 antiviral targets including Spike, Envelope, Membrane, 3CLPro, PLpro, Nucleocapsid N and C termini, RdRP, and host receptors—TLR2, TLR3, TLR7, and TLR8. Afterwards, mappain was subjected to in-vitro bioassay testing using inhibition 2E-induced cytokines (IL-6 and TNF-α) in human peripheral blood mononuclear cells, measured by ELISA; Amantadine as control. KEGG pathway enrichment analysis was further performed using network pharmacology to elucidate the mechanism. Mappain demonstrated a high binding score with all the targets, especially with the envelope protein (− 9.6 kcal/mol) and TLR2 (− 9.7 kcal/mol) compared to Amantadine (− 6.1 kcal/mol and − 5.5 kcal/mol, respectively). Mappain also significantly reduced the expression of 2E-induced Interleukin 6 (p ≤ 0.001) and tumour necrosis factor-alpha (p ≤ 0.01) in the PBMCs, when compared to Amantadine HCl. The KEGG Pathway enrichment analysis supports the anti-inflammatory potential of mappain in the virus-induced cytokine storm by specifically targeting TLR signalling and COVID-19 pathways.

MiR-574-5p in epigenetic regulation and Toll-like receptor signaling.

miR-574-5p is an unusual microRNA (miRNA) that is often upregulated or downregulated following exposure to irradiation or toxic chemicals; bacterial, parasitic or viral infection; and a variety of other disease conditions. Canonically, miR-574-5p epigenetically regulates the expression of many messenger RNAs (mRNAs) through miRNA-mediated posttranscriptional regulation, thereby affecting cellular physiology or pathophysiology and contributing to the pathogenesis or progression of a variety of diseases. However, recent studies have established that in addition to serving as a fine-tuning repressor of gene expression, miR-574-5p also stimulates gene expression as an endogenous ligand for Toll-like receptor-8/7 (TLR8/7). Indeed, the binding of miR-574-5p to TLR8/7 triggers the TLR signaling pathway, leading to the induction of interferons, inflammatory cytokines and autoimmune signaling. These findings suggest that miR-574-5p is not only an important epigenetic regulator of gene expression, but also an important regulator of immune and inflammatory responses. Abnormal miR-574-5p-TLR8/7 signaling has been shown to be tightly associated with inflammation-related cancers and a number of autoimmune disorders. miR-574-5p can serve as a potential biomarker for many diseases. Most importantly, miR-574-5p is a promising therapeutic target for the treatment or prevention of human disorders, especially infectious diseases, cancers and autoimmune diseases.

Different infant formulas can activate toll-like receptor 9 in vitro and inhibit interleukin 6 in human primary intestinal epithelial cells

PurposeNecrotizing enterocolitis (NEC) is the most severe gastrointestinal disease in preterm infants caused by an exaggerated intestinal epithelial immune activation. Several studies show that modulation of toll-like receptor 9 (TLR9) activity may have positive effects on preventing intestinal inflammatory mechanisms ultimately resulting in NEC development. In this study, the effect of various infant formulas (IF) and the probiotic strain Limosilactobacillus fermentum CECT5716 on TLR9 activation were analyzed in vitro.MethodsFirst, TLR4 and TLR9 expression was analyzed on human primary intestinal epithelial cells (P-IECs) by qPCR and Western blot analysis. Then genetically designed HEK-Dual™ hTLR9 (NF/IL8) reporter cells (HEK-Dual) were treated with different IFs, L. fermentum CECT5716, and different functional components to measure TLR9 activation via luminescence. Finally, the IFs were investigated in P-IECs to analyze TLR downstream signaling by Western blot analysis.ResultsIFs containing intact protein and L. fermentum CECT5716 activated TLR9 in HEK-Dual cells, but the functional components lactoferrin, L-5-methyltetrahydrofolate, and hydrolyzed whey proteins failed to activate TLR9. In P-IECs, the IFs induced increased phosphorylation of MAPK8/9 of the TLR signaling pathway and significantly reduced IL6 levels. Consistently, IL6 levels were increased in P-IECs when TLR9-signaling was inhibited. Interestingly, L. fermentum CECT5716 enhanced TLR9-signaling and increased NF-kappa-B inhibitor alpha-phosphorylation.ConclusionWe found out that the used control formula, prebiotic formula, prebiotic formula with hydrolyzed-protein, and L. fermentum CECT5716 reduce IL6 levels in human P-IECs through TLR9 activation. L. fermentum CECT5716 and the here tested IFs could be a promising approach for modulation of gut health in infants.

Systemic administration of a viral nanoparticle neoadjuvant prevents lung metastasis development through emergency myelopoiesis

ABSTRACT Cancer presents a significant public health concern, particularly in the context of metastatic disease. Surgical removal of primary tumors, while essential, can inadvertently heighten the risk of metastasis. Thus, there is a critical need for innovative neoadjuvant therapies capable of curtailing metastatic progression before or immediately following tumor resection. Addressing this imperative, the papaya mosaic virus nanoparticle (PapMV) has demonstrated potent immunostimulatory capabilities against both viruses and tumors, effectively hindering their proliferation. Our study reveals that PapMV exerts a protective effect against lung metastasis when administered systemically prior to tumor implantation or during the early stages of metastasis in various mouse models of cancer. This anti-tumor effect is initiated by the recruitment of myeloid cells in the lungs. These cells adopt a pro-inflammatory profile, secreting cytokines such as IFN-α, thus fostering a tumor microenvironment inhospitable to tumor progression. Crucially, this protective mechanism hinges on the presence of macrophages before treatment. TLR7 and IFN-I signaling pathways also play pivotal roles in this process. Furthermore, our findings demonstrate that PapMV triggers the activation of the bone marrow emergency response, which accounts for the influx of myeloid cells into the lungs. This study unveils a novel aspect of PapMV’s functionality. By bolstering the immune system, PapMV confers robust protection against metastasis at an early stage of disease progression. This discovery holds promise for therapeutic intervention, particularly as a preemptive measure prior to or just after surgical intervention.

Modulation of the Gut-Lung Axis by Water Kefir and Kefiran and Their Impact on Toll-like Receptor 3-Mediated Respiratory Immunity.

The beneficial effect of milk kefir on respiratory heath has been previously demonstrated; however, water kefir and kefiran in the context of respiratory viral infections have not been investigated. Water kefir and kefiran could be alternatives to milk kefir for their application in persons with lactose intolerance or milk allergy and could be incorporated into vegan diets. Using mice models, this work demonstrated that the oral administration of water kefir or kefiran can modulate the respiratory Toll-like receptor (TLR3)-mediated innate antiviral immunity and improve the resistance to respiratory syncytial virus (RSV) infection. The treatment of mice with water kefir or kefiran for 6 days improved the production of interferons (IFN-β and IFN-γ) and antiviral factors (Mx2, OAS1, RNAseL, and IFITM3) in the respiratory tract after the activation of the TLR3 signaling pathway, differentially modulated the balance of pro- and anti-inflammatory cytokines, reduced RSV replication, and diminished lung tissue damage. Maintaining a proper balance between anti-inflammatory and pro-inflammatory mediators is vital for ensuring an effective and safe antiviral immune response, and the results of this work show that water kefir and kefiran would help to maintain that balance promoting a controlled inflammatory response that defends against infection while minimizing tissue damage.

Glycine Mitigates Lipopolysaccharide Induced Neurotoxicity via Inhibition of TLR-4 Signaling Pathway in Developing Mice Brain

Background: Lipopolysaccharide (LPS) is an endotoxin of the gram-negative bacteria, playing a crucial role in systematic toxicity and cause neurotoxicity in immature brains. Glycine is non-essential amino acid, acting as a neurotransmitter, antioxidant and immune function regulator.Objective: To investigate the potential use of glycine inhibition of TLR-4 receptor to reduce LPS induced neurodegeneration in the developing brain of post-natal day 7 (PND-7) mice. Materials and Methods: A total of 12 PND-7 mice were included in this experimental study from Feb. 2023 to May 2023 at NMMRC, Peshawar. PND-7 mice were randomly distributed into four groups, a control group, a LPS group, LPS+Gly group and Gly group. LPS (250ìg /kg) was administered to LPS group. Glycine (1g/kg) was injected after LPS administration to LPS+Gly group and Gly group mice. After 4hr of the drug treatment, all the PND-7 mice were sacrificed for Western blot analysis. ImageJ software was used for the densitometry of the blots. One way ANOVA and post-hoc tukey tests through Prism graph-5 were applied for statistical analysis. P-value=0.05 was considered statistically significant. Results: Significant differences were observed in the assessed markers in of PND 7 mice brains. Post hoc tukey test revealed significant changes (p<0.01) in the TLR-4 along with BAX, Casp-3, PARP-1and Bcl-2 levels in LPS group. However, significant decrease was observed in TLR-4 levels along with successful amelioration of BAX, Bcl-2, Casp-3 and PARP-1 level in LPS + Gly group as compared to LPS group. Conclusion: Glycine administration significantly improved LPS induced neurodegeneration in brain of the PND-7 mice. Keywords: Apoptosis, Caspase-3, Glycine, Lipopolysaccharide, Neurodegeneration, PARP-1, TLR-4 signaling pathway.

Mesenchymal stem cells: a novel therapeutic approach for feline inflammatory bowel disease

BackgroundInflammatory bowel disease (IBD) poses a significant and growing global health challenge, affecting both humans and domestic cats. Research on feline IBD has not kept pace with its widespread prevalence in human populations. This study aimed to develop a model of feline IBD by incorporating dextran sulfate sodium (DSS) to evaluate the therapeutic potential of MSCs and to elucidate the mechanisms that enhance their action.MethodsWe conducted a comprehensive clinical assessment, including magnetic resonance imaging (MRI), endoscopy, and histopathological examination. Additionally, alterations in intestinal microbiota were characterized by 16 S rDNA sequencing, and the influence of MSCs on IBD-related gene expression was investigated through transcriptome analysis.ResultsAccording to our findings, MSC treatment significantly mitigated DSS-induced clinical manifestations, reduced inflammatory cell infiltration, decreased the production of inflammatory mediators, and promoted mucosal repair. Regarding the intestinal microbiota, MSC intervention effectively corrected the DSS-induced dysbiosis, increasing the presence of beneficial bacteria and suppressing the proliferation of harmful bacteria. Transcriptome analysis revealed the ability of MSCs to modulate various inflammatory and immune-related signaling pathways, including cytokine-cytokine receptor interactions, TLR signaling pathways, and NF-κB pathways.ConclusionThe collective findings indicate that MSCs exert multifaceted therapeutic effects on IBD, including the regulation of intestinal microbiota balance, suppression of inflammatory responses, enhancement of intestinal barrier repair, and modulation of immune responses. These insights provide a solid scientific foundation for employing MSCs as an innovative therapeutic strategy for IBD and pave the way for future clinical explorations.

Lactobacillus plantarum LP104 improved intestinal and brain inflammation by modulating TLR4 pathway and gut flora in alcohol liver injury mice

In this study, Lactobacillus plantarum LP104 (LP104) originating from kimchi was treated to C57BL/6N mice fed a chronic-plus-single-binge ethanol diet for ten days, aiming to evaluate the effects of the probiotics on intestinal and brain inflammation in the alcohol-induced liver injury model. Dietary supplementation with LP104 significantly reduced the concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) in alcoholic hepatic injury mice. The 16S rDNA sequencing results inferred that LP104 modulated the intestinal microbiota by depleting inflammation-related bacterial genera Proteobacteria and enriching Lactobacillus and Roseburia. Furthermore, LP104 intervention attenuated alcohol-induced gut inflammation by the TLR4 signaling pathway, which regulated the expressions of intestinal tight junction proteins such as ZO-1, Claudin-1 and Occludin. Subsequently, LP104 intake exerted neuroprotection by restoring neurotrophic factor levels and the blood-brain barrier (BBB) function to decrease lipopolysaccharide (LPS) levels in the serum. The western blotting results suggested LP104 ameliorated alcohol-induced brain inflammation by inhibiting the LPS/TLR4 signaling pathway in mice. Spearman's correlation analysis demonstrated that differential intestinal bacterial taxa were connected with the expressions of inflammation-related proteins in both gut and brain of alcohol liver injury mice.