Role of TLR4 Receptor Complex in the Regulation of the Innate Immune Response by Fibronectin

The role of the gut microbiota in tumor, immunity, and immunotherapy

In recent years, with the deepening understanding of the gut microbiota, it has been recognized to play a significant role in the development and progression of diseases. Particularly in gastrointestinal tumors, the gut microbiota influences tumor growth by dysbiosis, release of bacterial toxins, and modulation of host signaling pathways and immune status. Immune checkpoint inhibitors (ICIs) have greatly improved cancer treatment efficacy by enhancing immune cell responses. Current clinical and preclinical studies have demonstrated that the gut microbiota and its metabolites can enhance the effectiveness of immunotherapy. Furthermore, certain gut microbiota can serve as biomarkers for predicting immunotherapy responses. Interventions targeting the gut microbiota for the treatment of gastrointestinal diseases, especially colorectal cancer (CRC), include fecal microbiota transplantation, probiotics, prebiotics, engineered bacteria, and dietary interventions. These approaches not only improve the efficacy of ICIs but also hold promise for enhancing immunotherapy outcomes. In this review, we primarily discuss the role of the gut microbiota and its metabolites in tumors, host immunity, and immunotherapy.

Influence of Maqian essential oil on gut microbiota and immunoresponses in type 1 diabetes: In silico study

Diversity and homeostasis of gut bacterial composition is highly associated with the pathogenesis of insulin dysfunction and type 1 diabetes melittus (T1D), hence emerged in parallel with the activation of autoimmunity. We aimed to study the bioactive potential of essential oil from Zanthoxylum myriacanthum var. pubescens Huang (Maqian) through computational approaches. Twelve chemical constituents derived from Maqian essential oil were docked with selected proteins (i.e., 3pig, 1kho, 7dmq, 4m4d, 2z65, 4glp, and 3fxi) in which are involved in gut microbiota modulation in T1D. Subsequently, the prediction of bioavailability properties of the small molecules were evaluated. Among all chemical constituents, the post-docking interaction analysis demonstrated that α-phellandrene exhibits the strongest binding affinity and induces gut microbiota modulation with β-fructofuranosidase from Bifidobacterium longum. The current result revealed the potential of 3-Carene and α-Pinene in inducing specific changes in gut microbiota downregulating Clostridium perfringens and quenching Leptotrichia shahii respectively. β-Pinene possess exceptionally strong binding affinity that effectively disrupt the interaction between lipopolysaccharide and its cognate receptors, while α-Phellandrene was exhibited the uppermost binding affinity with TLR4/MD2 and could likely target TLR4 stimulating lipopolysaccharide. Our results are the first to report on the gut microbiota modulation effects of α-Phellandrene and β-Phellandrene via actions on LPS binding to CD14 and the TLR4 co-receptor signaling. In conclusion, our findings based on computational approaches, small molecules from Maqian present as promising agents which could regulate inflammatory response and modulate gut microbiota in type 1 diabetes mellitus.

Detection of the Level of Interleukin-8 in the Serum of Burn Patients by ELISA Technique

Burn injuries are the most frequent injuries in the world, with a death rate of 2.3-3.6%. Children and people of working age constitute 85-90% of the burn cases. Burn injury results in metabolic problems, a generalized inflammatory response, inefficient energy use, and other physiological alternations that may cause organ and system dysfunction and sepsis. Sepsis is mostly caused by multiple organ failures and has unique characteristics in burn injuries, which make it the most dangerous complication of burn injuries. This study aimed to investigate the correlation between sepsis in burn patients and the level of interleukin 8 (IL-8) in their serum. In total, 60 patients with burn injuries were included in this study. Blood samples were obtained from 60 burn patients and 30 healthy individuals as controls. The BacT/Alert and Vitek2 systems were used to identify the bacteria and determine their susceptibility to these bacteria. Moreover, enzyme-linked immunosorbent assay (ELISA) was used to determine IL-8 serum levels. Based on the results, elevated levels of IL-8 were observed in the serum of burn patients, compared to healthy individuals. Concentration of IL-8 was significantly higher in patients with sepsis, compared to healthy individuals without sepsis.

Mechanism of TLR4 mediated immune effect in transfusion-induced acute lung injury based on Slit2/Robo4 signaling pathway

BACKGROUND

Transfusion-related acute lung injury (TRALI) is the infusion of blood or blood system.

OBJECTIVE

To explore the mechanism of TLR4-mediated T cell immune effect in TRALI.

METHODS

In this animal study, a mouse model of LPS-induced TRALI was established. Sixty adult C57/BL6 mice (wild-type, WT) were randomly divided into 5 groups: 1) normal WT type, 2) LPS control group of WT type lipopolysaccharide, 3) WT type TRALI group (LPS + MHC-I mAb), 4) (TLR4 antibody) lipopolysaccharide LPS control group, 5) (TLR4 antibody) TRALI group (LPS + MHC-I mAb). Mice were injected with LPS (0.1 mg/kg) and MHC-I mAb (2 mg/kg) into the tail vein. H&E staining was performed to detect pathological features. The myeloperoxidase (MPO) activity and the level of inflammatory cytokines in lung tissue homogenate supernatant were measured. Blood, spleen single-cell suspension, and bronchoalveolar lavage fluid were collected to detect the ratio of Treg and Th17 cells by flow cytometry. RT-PCR and WB were used to detect mRNA or protein expression.

RESULTS

TLR4 mAb treatment alleviated the pathogenesis of LPS-induced TRALI in vivo, the MPO activity, and the level of proinflammatory factors in lung tissues. TLR4 exerted its function by changing of Treg/Th17 ratio via the SLIT2/ROBO4 signaling pathway and downregulating CDH5 and SETSIP.

CONCLUSION

TLR4 mediates immune response in the LPS-induced TRALI model through the SLIT2/ROBO4 signaling pathway.

Anti-Inflammatory Role of TRPV4 in Human Macrophages

The pathology of skin immune diseases such as atopic dermatitis is closely related to the overproduction of cytokines by macrophages. Although the pathological functions of macrophages in skin are known, mechanisms of how they detect the tissue environment remain unknown. TRPV4, a nonselective cation channel with high Ca2+ permeability, is activated at physiological temperatures from 27 to 35°C and involved in the functional control of macrophages. However, the relationship between TRPV4 function in macrophages and skin immune disease is unclear. In this study, we demonstrate that TRPV4 activation inhibits NF-κB signaling, resulting in the suppression of IL-1β production in both human primary monocytes and macrophages derived from human primary monocytes. A TRPV4 activator also inhibited the differentiation of human primary monocytes into GM-CSF M1 macrophages but not M-CSF M2 macrophages. We also observed a significant increase in the number of inducible NO synthase-positive/TRPV4-negative dermal macrophages in atopic dermatitis compared with healthy human skin specimens. Our findings provide insight into the physiological relevance of TRPV4 to the regulation of macrophages during homeostasis maintenance and raise the potential for TRPV4 to be an anti-inflammatory target.

Disulfiram ameliorates ischemia/reperfusion-induced acute kidney injury by suppressing the caspase-11-GSDMD pathway

Acute kidney injury (AKI) is a serious condition with high mortality. The most common cause is kidney ischemia/reperfusion (IR) injury, which is thought to be closely related to pyroptosis. Disulfiram is a well-known alcohol abuse drug, and recent studies have shown its ability to mitigate pyroptosis in mouse macrophages. This study investigated whether disulfiram could improve IR-induced AKI and elucidated the possible molecular mechanism. We generated an IR model in mouse kidneys and a hypoxia/reoxygenation (HR) injury model with murine tubular epithelial cells (MTECs). The results showed that IR caused renal dysfunction in mice and triggered pyroptosis in renal tubular epithelial cells, and disulfiram improved renal impairment after IR. The expression of proteins associated with the classical pyroptosis pathway (Nucleotide-binding oligomeric domain (NOD)-like receptor protein 3 (NLRP3), apoptosis-related specific protein (ASC), caspase-1, N-GSDMD) and nonclassical pyroptosis pathway (caspase-11, N-GSDMD) were upregulated after IR. Disulfiram blocked the upregulation of nonclassical but not all classical pyroptosis pathway proteins (NLRP3 and ASC), suggesting that disulfiram might reduce pyroptosis by inhibiting the caspase-11-GSDMD pathway. In vitro, HR increased intracellular ROS levels, the positive rate of PI staining and LDH levels in MTECs, all of which were reversed by disulfiram pretreatment. Furthermore, we performed a computer simulation of the TIR domain of TLR4 using homology modeling and identified a small molecular binding energy between disulfiram and the TIR domain. We concluded that disulfiram might inhibit pyroptosis by antagonizing TLR4 and inhibiting the caspase-11-GSDMD pathway.

Recent Progress on the Role of Fibronectin in Tumor Stromal Immunity and Immunotherapy

As a major component of the stromal microenvironment of various solid tumors, the extracellular matrix (ECM) has attracted increasing attention in cancer-related studies. ECM in the tumor stroma not only provides an external barrier and framework for tumor cell adhesion and movement, but also acts as an active regulator that modulates the tumor microenvironment, including stromal immunity. Fibronectin (Fn), as a core component of the ECM, plays a key role in the assembly and remodeling of the ECM. Hence, understanding the role of Fn in the modulation of tumor stromal immunity is of great importance for cancer immunotherapy. Hence, in-depth studies on the underlying mechanisms of Fn in tumors are urgently needed to clarify the current understanding and issues and to identify new and specific targets for effective diagnosis and treatment purposes. In this review, we summarize the structure and role of Fn, its potent derivatives in tumor stromal immunity, and their biological effects and mechanisms in tumor development. In addition, we discuss the novel applications of Fn in tumor treatment. Therefore, this review can provide prospective insight into Fn immunotherapeutic applications in tumor treatment.

ITRAQ-based quantitative proteomics analysis of forest musk deer with pneumonia

Pneumonia can seriously threaten the life of forest musk deer (FMD, an endangered species). To gain a comprehensive understanding of pneumonia pathogenesis in FMD, iTRAQ-based proteomics analysis was performed in diseased (Pne group) lung tissues of FMD that died of pneumonia and normal lung tissues (Ctrl group) of FMD that died from fighting against each other. Results showed that 355 proteins were differentially expressed (fold change ≥ 1.2 and adjusted P-value < 0.05) in Pne vs. Ctrl. GO/KEGG annotation and enrichment analyses showed that dysregulated proteins might play vital roles in bacterial infection and immunity. Given the close association between bacterial infection and pneumonia, 32 dysregulated proteins related to Staphylococcus aureus infection, bacterial invasion of epithelial cells, and pathogenic Escherichia coli infection were screened out. Among these 32 proteins, 13 proteins were mapped to the bovine genome. Given the close phylogenetic relationships of FMD and bovine, the protein-protein interaction networks of the above-mentioned 13 proteins were constructed by the String database. Based on the node degree analysis, 5 potential key proteins related to pneumonia-related bacterial infection in FMD were filtered out. Moreover, 85 dysregulated proteins related to the immune system process were identified given the tight connection between immune dysregulation and pneumonia pathogenesis. Additionally, 12 proteins that might function as crucial players in pneumonia-related immune response in FMD were screened out using the same experimental strategies described above. In conclusion, some vital proteins, biological processes, and pathways in pneumonia development were identified in FMD.

Fibronectin Functions as a Selective Agonist for Distinct Toll-like Receptors in Triple-Negative Breast Cancer

The microenvironment of tumors is characterized by structural changes in the fibronectin matrix, which include increased deposition of the EDA isoform of fibronectin and the unfolding of the fibronectin Type III domains. The impact of these structural changes on tumor progression is not well understood. The fibronectin EDA (FnEDA) domain and the partially unfolded first Type III domain of fibronectin (FnIII-1c) have been identified as endogenous damage-associated molecular pattern molecules (DAMPs), which induce innate immune responses by serving as agonists for Toll-Like Receptors (TLRs). Using two triple-negative breast cancer (TNBC) cell lines MDA-MB-468 and MDA-MB-231, we show that FnEDA and FnIII-1c induce the pro-tumorigenic cytokine, IL-8, by serving as agonists for TLR5 and TLR2, the canonical receptors for bacterial flagellin and lipoprotein, respectively. We also find that FnIII-1c is not recognized by MDA-MB-468 cells but is recognized by MDA-MB-231 cells, suggesting a cell type rather than ligand specific utilization of TLRs. As IL-8 plays a major role in the progression of TNBC, these studies suggest that tumor-induced structural changes in the fibronectin matrix promote an inflammatory microenvironment conducive to metastatic progression.

Matrix Metalloproteinases Inhibition by Doxycycline Rescues Extracellular Matrix Organization and Partly Reverts Myofibroblast Differentiation in Hypermobile Ehlers-Danlos Syndrome Dermal Fibroblasts: A Potential Therapeutic Target?

Hypermobile Ehlers-Danlos syndrome (hEDS) is the most frequent type of EDS and is characterized by generalized joint hypermobility and musculoskeletal manifestations which are associated with chronic pain, and mild skin involvement along with the presence of more than a few comorbid conditions. Despite numerous research efforts, no causative gene(s) or validated biomarkers have been identified and insights into the disease-causing mechanisms remain scarce. Variability in the spectrum and severity of symptoms and progression of hEDS patients’ phenotype likely depend on a combination of age, gender, lifestyle, and the probable multitude of genes involved in hEDS. However, considering the clinical overlap with other EDS forms, which lead to abnormalities in extracellular matrix (ECM), it is plausible that the mechanisms underlying hEDS pathogenesis also affect the ECM to a certain extent. Herein, we performed a series of in vitro studies on the secretome of hEDS dermal fibroblasts that revealed a matrix metalloproteinases (MMPs) dysfunction as one of the major disease drivers by causing a detrimental feedback loop of excessive ECM degradation coupled with myofibroblast differentiation. We demonstrated that doxycycline-mediated inhibition of MMPs rescues in hEDS cells a control-like ECM organization and induces a partial reversal of their myofibroblast-like features, thus offering encouraging clues for translational studies confirming MMPs as a potential therapeutic target in hEDS with the expectation to improve patients’ quality of life and alleviate their disabilities.

Nucleomodulin BspJ as an effector promotes the colonization of Brucella abortus in the host

BACKGROUND

Brucella infection induces brucellosis, a zoonotic disease. The intracellular circulation process and virulence of Brucella mainly depend on its type IV secretion system (T4SS) expressing secretory effectors. Secreted protein BspJ is a nucleomodulin of Brucella that invades the host cell nucleus. BspJ mediates host energy synthesis and apoptosis through interaction with proteins. However, the mechanism of BspJ as it affects the intracellular survival of Brucella remains to be clarified.

OBJECTIVES

To verify the functions of nucleomodulin BspJ in Brucella's intracellular infection cycles.

METHODS

Constructed Brucella abortus BspJ gene deletion strain (B. abortus ΔBspJ) and complement strain (B. abortus pBspJ) and studied their roles in the proliferation of Brucella both in vivo and in vitro.

RESULTS

BspJ gene deletion reduced the survival and intracellular proliferation of Brucella at the replicating Brucella-containing vacuoles (rBCV) stage. Compared with the parent strain, the colonization ability of the bacteria in mice was significantly reduced, causing less inflammatory infiltration and pathological damage. We also found that the knockout of BspJ altered the secretion of cytokines (interleukin [IL]-6, IL-1β, IL-10, tumor necrosis factor-α, interferon-γ) in host cells and in mice to affect the intracellular survival of Brucella.

CONCLUSIONS

BspJ is extremely important for the circulatory proliferation of Brucella in the host, and it may be involved in a previously unknown mechanism of Brucella's intracellular survival.

The RNA binding protein Quaking represses splicing of the Fibronectin EDA exon and downregulates the interferon response

Quaking (QKI) controls RNA metabolism in many biological processes including innate immunity, where its roles remain incompletely understood. To illuminate these roles, we performed genome scale transcriptome profiling in QKI knockout cells with or without poly(I:C) transfection, a double-stranded RNA analog that mimics viral infection. Analysis of RNA-sequencing data shows that QKI knockout upregulates genes induced by interferons, suggesting that QKI is an immune suppressor. Furthermore, differential splicing analysis shows that QKI primarily controls cassette exons, and among these events, we noted that QKI silences splicing of the extra domain A (EDA) exon in fibronectin (FN1) transcripts. QKI knockout results in elevated production and secretion of FN1-EDA protein, which is a known activator of interferons. Consistent with an upregulation of the interferon response in QKI knockout cells, our results show reduced production of dengue virus-2 and Japanese encephalitis virus in these cells. In conclusion, we demonstrate that QKI downregulates the interferon system and attenuates the antiviral state.

Proteome Characterization of Glaucoma Aqueous Humor

Glaucoma is the leading cause of irreversible blindness worldwide. The proteome characterization of glaucoma is not clearly understood. A total of 175 subjects, including 57 primary acute angle-closure glaucoma (PAACG), 50 primary chronic angle-closure glaucoma (PCACG), 35 neovascular glaucoma (NVG), and 33 cataract patients, were enrolled and comparison proteomic analysis was provided. The samples were randomly divided into discovery group or validation group, whose aqueous humor proteome was analyzed by data-independent acquisition or by parallel reaction monitoring. The common proteome features of three types of glaucoma were immune response, lipid metabolism, and cell death. Three proteins, VTN, SERPIND1, and CD14, showed significant upregulation in glaucoma and could discriminate glaucoma from cataract. Mutual differential proteomic analysis of PAACG, PCACG, and NVG showed different proteome characterization of the three types of glaucoma. NVG was characterized with activated angiogenesis. PAACG was characterized with activation of inflammation response. SERPIND1 was discovered to play vital role in glaucoma occurrences, which is associated with eye transparency decrease and glucose metabolism. This study would provide insights in understanding proteome characterization of glaucoma and benefit the clinical application of AH proteome.

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Aqueous humor proteome of different glaucoma (PACG, NVG) was profiled.

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Potential protein biomarkers for glaucoma were proposed.

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Potential mechanism of glaucoma was described.

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SERPIND1 was discovered to have potential value for glaucoma diagnosis.

Ergosta-7, 9 (11), 22-trien-3β-ol Interferes with LPS Docking to LBP, CD14, and TLR4/MD-2 Co-Receptors to Attenuate the NF-κB Inflammatory Pathway In Vitro and Drosophila

Ergosta-7, 9 (11), 22-trien-3β-ol (EK100) was isolated from Cordyceps militaris, which has been used as a traditional anti-inflammatory medicine. EK100 has been reported to attenuate inflammatory diseases, but its anti-inflammatory mechanism is still unclear. We were the first to investigate the effect of EK100 on the Toll-like receptor 4 (TLR4)/nuclear factor of the κ light chain enhancer of B cells (NF-κB) signaling in the lipopolysaccharide (LPS)-stimulated RAW264.7 cells and the green fluorescent protein (GFP)-labeled NF-κB reporter gene of Drosophila. EK100 suppressed the release of the cytokine and attenuated the mRNA and protein expression of pro-inflammatory mediators. EK100 inhibited the inhibitor kappa B (IκB)/NF-κB signaling pathway. EK100 also inhibited phosphatidylinositol-3-kinase (PI3K)/Protein kinase B (Akt) signal transduction. Moreover, EK100 interfered with LPS docking to the LPS-binding protein (LBP), transferred to the cluster of differentiation 14 (CD14), and bonded to TLR4/myeloid differentiation-2 (MD-2) co-receptors. Compared with the TLR4 antagonist, resatorvid (CLI-095), and dexamethasone (Dexa), EK100 suppressed the TLR4/AKT signaling pathway. In addition, we also confirmed that EK100 attenuated the GFP-labeled NF-κB reporter gene expression in Drosophila. In summary, EK100 might alter LPS docking to LBP, CD14, and TLR4/MD-2 co-receptors, and then it suppresses the TLR4/NF-κB inflammatory pathway in LPS-stimulated RAW264.7 cells and Drosophila.

Autophagy, Unfolded Protein Response, and Neuropilin-1 Cross-Talk in SARS-CoV-2 Infection: What Can Be Learned from Other Coronaviruses

The COVID-19 pandemic is caused by the 2019-nCoV/SARS-CoV-2 virus. This severe acute respiratory syndrome is currently a global health emergency and needs much effort to generate an urgent practical treatment to reduce COVID-19 complications and mortality in humans. Viral infection activates various cellular responses in infected cells, including cellular stress responses such as unfolded protein response (UPR) and autophagy, following the inhibition of mTOR. Both UPR and autophagy mechanisms are involved in cellular and tissue homeostasis, apoptosis, innate immunity modulation, and clearance of pathogens such as viral particles. However, during an evolutionary arms race, viruses gain the ability to subvert autophagy and UPR for their benefit. SARS-CoV-2 can enter host cells through binding to cell surface receptors, including angiotensin-converting enzyme 2 (ACE2) and neuropilin-1 (NRP1). ACE2 blockage increases autophagy through mTOR inhibition, leading to gastrointestinal complications during SARS-CoV-2 virus infection. NRP1 is also regulated by the mTOR pathway. An increased NRP1 can enhance the susceptibility of immune system dendritic cells (DCs) to SARS-CoV-2 and induce cytokine storm, which is related to high COVID-19 mortality. Therefore, signaling pathways such as mTOR, UPR, and autophagy may be potential therapeutic targets for COVID-19. Hence, extensive investigations are required to confirm these potentials. Since there is currently no specific treatment for COVID-19 infection, we sought to review and discuss the important roles of autophagy, UPR, and mTOR mechanisms in the regulation of cellular responses to coronavirus infection to help identify new antiviral modalities against SARS-CoV-2 virus.

Fibronectin in development and wound healing

Fibronectin structure and composition regulate contextual cell signaling. Recent advances have been made in understanding fibronectin and its role in tissue organization and repair. This review outlines fibronectin splice variants and their functions, evaluates potential therapeutic strategies targeting or utilizing fibronectin, and concludes by discussing potential future directions to modulate fibronectin function in development and wound healing.

Mechanobiological Principles Influence the Immune Response in Regeneration: Implications for Bone Healing

A misdirected or imbalanced local immune composition is often one of the reasons for unsuccessful regeneration resulting in scarring or fibrosis. Successful healing requires a balanced initiation and a timely down-regulation of the inflammation for the re-establishment of a biologically and mechanically homeostasis. While biomaterial-based approaches to control local immune responses are emerging as potential new treatment options, the extent to which biophysical material properties themselves play a role in modulating a local immune niche response has so far been considered only occasionally. The communication loop between extracellular matrix, non-hematopoietic cells, and immune cells seems to be specifically sensitive to mechanical cues and appears to play a role in the initiation and promotion of a local inflammatory setting. In this review, we focus on the crosstalk between ECM and its mechanical triggers and how they impact immune cells and non-hematopoietic cells and their crosstalk during tissue regeneration. We realized that especially mechanosensitive receptors such as TRPV4 and PIEZO1 and the mechanosensitive transcription factor YAP/TAZ are essential to regeneration in various organ settings. This indicates novel opportunities for therapeutic approaches to improve tissue regeneration, based on the immune-mechanical principles found in bone but also lung, heart, and skin.

Non-celiac wheat sensitivity: rationality and irrationality of a gluten-free diet in individuals affected with non-celiac disease: a review

Non-celiac gluten or wheat sensitivity (NCWS) is a “clinical entity induced by the ingestion of wheat leading to intestinal and/or extraintestinal symptoms that improve once the wheat-containing foodstuff is removed from the diet, and celiac disease and wheat allergy have been excluded”. This mostly accepted definition raises several points that remain controversial on this condition. In the present review, the authors summarize the most recent advances in the clinic and research on NCWS through an accurate analysis of different studies. We screened PubMed, Medline, Embase, and Scopus using the keywords “non-celiac gluten sensitivity”, “non-celiac wheat sensitivity”, and “diagnosis”. We would like to emphasize two main points, including (A) the controversial clinical and etiological aspects in different trials and experiences with particular attention to the Salerno criteria for the diagnosis of NCWS and (B) the histological aspects. The etiology of NCWS remains controversial, and the relationship with irritable bowel syndrome is obscure. Histologically, the duodenal mucosa may show a variable pattern from unremarkable to a slight increase in the number of T lymphocytes in the superficial epithelium of villi. The endorsement of this disease is based on a positive response to a gluten-free diet for a limited period, followed by the reappearance of symptoms after gluten challenge. The Salerno expert criteria may help to diagnose NCWS accurately. Social media and inaccurate interpretation of websites may jeopardize the diagnostic process if individuals self-label as gluten intolerant.

Key Player in Cardiac Hypertrophy, Emphasizing the Role of Toll-Like Receptor 4

Toll-like receptor 4 (TLR4), a key pattern recognition receptor, initiates the innate immune response and leads to chronic and acute inflammation. In the past decades, accumulating evidence has implicated TLR4-mediated inflammatory response in regulation of myocardium hypertrophic remodeling, indicating that regulation of the TLR4 signaling pathway may be an effective strategy for managing cardiac hypertrophy's pathophysiology. Given TLR4's significance, it is imperative to review the molecular mechanisms and roles underlying TLR4 signaling in cardiac hypertrophy. Here, we comprehensively review the current knowledge of TLR4-mediated inflammatory response and its interaction ligands and co-receptors, as well as activation of various intracellular signaling. We also describe the associated roles in promoting immune cell infiltration and inflammatory mediator secretion, that ultimately cause cardiac hypertrophy. Finally, we provide examples of some of the most promising drugs and new technologies that have the potential to attenuate TLR4-mediated inflammatory response and prevent or reverse the ominous cardiac hypertrophy outcomes.