Local and systemic effects of interleukin-6 (IL-6) in inflammation and cancer

Chlamydia trachomatis T3SS Effector CT622 Induces Proinflammatory Cytokines Through TLR2/TLR4-Mediated MAPK/NF-κB Pathways in THP-1 Cells

BACKGROUND

The pathogenesis of Chlamydia trachomatis is associated with the induction of the host inflammatory response; however, the precise underlying molecular mechanisms remain poorly understood.

METHODS

CT622, a T3SS effector protein, has an important role in the pathogenesis of C trachomatis; however, whether CT622 can induce a host inflammatory response is not understood. Our findings demonstrate that CT622 induces the expression of interleukins 6 and 8 (IL-6 and IL-8). Mechanistically, these effects involve the activation of the MAPK/NF-κB signaling pathways (mitogen-activated protein kinase/nuclear factor κB).

RESULTS

Interestingly, we demonstrated that the suppression of toll-like receptor 4 using small interfering RNA markedly reduced the phosphorylation of ERK, p38, JNK, and IκBα, concomitant with a significant decrease in IL-6 and IL-8 secretion. Conversely, disruption of toll-like receptor 2 abrogated the CT622-induced upregulation of IL-8 and activation of ERK, whereas IL-6 expression and p38, JNK, and IκBα phosphorylation were unaffected.

CONCLUSIONS

Taken together, these results indicate that CT622 contributes to the inflammatory response through the toll-like receptor 2/4-mediated MAPK/NF-κB pathways, which provides insight into the molecular pathology of C trachomatis infection.

Effect of intraoperative blood transfusion during maternal cesarean section on serum electrolytes and inflammatory response plus cellular immune response: A retrospective study

Analyzing the effect of intraoperative autotransfusion on serum electrolytes, inflammatory response and cellular immune response in puerperae undergoing cesarean section. This study is a retrospective study of 60 women who underwent cesarean section in our hospital from January 2022 to January 2023. The subjects were divided into 2 groups according to the blood transfusion mode of the patients. The differences in blood transfusion volume, blood transfusion volume, serum electrolyte, inflammatory response, cellular immune function, coagulation function and prognosis were compared between the 2 groups. The intraoperative blood transfusion volume, postoperative feeding time, the activity time since getting out of bed, the time of physical recovery and hospital stay in the observation group were lower compared to those of the control group, but the intraoperative crystal infusion volume and the colloid infusion volume in the observation group were higher compared to those of the control group (P < .05). Ca2+ concentrations of the observation group and the control group were lower compared with those of their same groups before surgery (P < .05), however, there were no statistically significant differences in the comparison of the Ca2+ concentrations between the observation group and the control group (P > .05). At 1d postoperatively, IL-1β, IL-6 and granulocyte-macrophage colony-stimulating factor (GM-CSF) were all higher (P < .05) and CD3+, CD4+ and CD4+/CD8+ were all lower (P < .05) in the observation group and the control group compared with those of their same groups before surgery. The IL-1 β, IL-6, and GM-CSF of the observation group were decreased compared to those of the control group (P < .05) and CD3+, CD4+, CD4+/CD8+ of the observation group were elevated compared to those of the control group (P < .05). Both autotransfusion and allogeneic blood transfusions during maternal cesarean section can attenuate the inflammatory response and have no significant inhibition of coagulation, and autotransfusion have less effect on the cellular immune response, are more effective in attenuating the inflammatory response, and significantly improve prognosis, although changes in Ca2+ concentration after transfusion require attention.

Transpiration-Inspired Fabric Dressing for Acceleration Healing of Wound Infected with Biofilm

In chronic wound management, efficacious handling of exudate and bacterial infections stands as a paramount challenge. Here a novel biomimetic fabric, inspired by the natural transpiration mechanisms in plants, is introduced. Uniquely, the fabric combines a commercial polyethylene terephthalate (PET) fabric with asymmetrically grown 1D rutile titanium dioxide (TiO2) micro/nanostructures, emulating critical plant features: hierarchically porous networks and hydrophilic water conduction channels. This structure endows the fabric with exceptional antigravity wicking-evaporation performance, evidenced by a 780% one-way transport capability and a 0.75 g h-1 water evaporation rate, which significantly surpasses that of conventional moisture-wicking textiles. Moreover, the incorporated 1D rutile TiO2 micro/nanostructures present solar-light induced antibacterial activity, crucial for disrupting and eradicating wound biofilms. The biomimetic transpiration fabric is employed to drain exudate and eradicate biofilms in Staphylococcus aureus (S. aureus)-infected wounds, demonstrating a much faster infection eradication capability compared to clinically common ciprofloxacin irrigation. These findings illuminate the path for developing high-performance, textile-based wound dressings, offering efficient clinical platforms to combat biofilms associated with chronic wounds.

Study on the mechanism of puerarin against osteoarthritis from ferroptosis based on network pharmacology and bioinformatics

Network pharmacology and bioinformatics were used to study puerarin's molecular mechanism in treating osteoarthritis from the perspective of ferroptosis, revealing a new treatment target. Ferroptosis-related targets were obtained from FerrDb. Puerarin action targets were retrieved from TCMSP, Pharmmappe, SwissTargetPrediction, and Targetnet databases, and supplemented with PubMed. The gene expression profiles of GSE12021, GSE55235, and GSE82107 were obtained using "Osteoarthritis" as the search term in the GEO database, and the differential expression gene screening analysis was performed for osteoarthritis. The intersection targets between puerarin, iron death, and osteoarthritis were obtained using Venn diagrams. GO and KEGG analyses were conducted with R software. Molecular docking and visualization of puerarin and core targets were performed using Autodock Vina and PyMol software. The effects of puerarin on the cell viability and the TNFα, IL6, and Ilβ levels of human inflammation articular chondrocytes were tested in vitro experiments. Puerarin, ferroptosis, and osteoarthritis share four targets: PLIN2, PTGS2, VEGFA, and IL6. GO enrichment analysis showed that puerarin maintained the blood-brain barrier, regulated peptide serine phosphorylation, and had anti-inflammatory effects. KEGG analysis showed that puerarin's anti-inflammatory effects were mainly through VEGF, IL-17, C-type lectin receptor, HIF-1, TNF, and other signaling pathways. Puerarin closely bound PLIN2, PTGS2, VEGFA, and IL6 targets in molecular docking. In vitro, puerarin prevented osteoarthritis. Network pharmacology and bioinformatics explained puerarin's multi-target and multi-pathway treatment of OA, which may be related to ferroptosis, and confirmed its anti-inflammatory effect.

Interorgan communication networks in the kidney-lung axis

The homeostasis and health of an organism depend on the coordinated interaction of specialized organs, which is regulated by interorgan communication networks of circulating soluble molecules and neuronal connections. Many diseases that seemingly affect one primary organ are really multiorgan diseases, with substantial secondary remote organ complications that underlie a large part of their morbidity and mortality. Acute kidney injury (AKI) frequently occurs in critically ill patients with multiorgan failure and is associated with high mortality, particularly when it occurs together with respiratory failure. Inflammatory lung lesions in patients with kidney failure that could be distinguished from pulmonary oedema due to volume overload were first reported in the 1930s, but have been largely overlooked in clinical settings. A series of studies over the past two decades have elucidated acute and chronic kidney-lung and lung-kidney interorgan communication networks involving various circulating inflammatory cytokines and chemokines, metabolites, uraemic toxins, immune cells and neuro-immune pathways. Further investigations are warranted to understand these clinical entities of high morbidity and mortality, and to develop effective treatments.

Gut liver brain axis in diseases: the implications for therapeutic interventions

Gut-liver-brain axis is a three-way highway of information interaction system among the gastrointestinal tract, liver, and nervous systems. In the past few decades, breakthrough progress has been made in the gut liver brain axis, mainly through understanding its formation mechanism and increasing treatment strategies. In this review, we discuss various complex networks including barrier permeability, gut hormones, gut microbial metabolites, vagus nerve, neurotransmitters, immunity, brain toxic metabolites, β-amyloid (Aβ) metabolism, and epigenetic regulation in the gut-liver-brain axis. Some therapies containing antibiotics, probiotics, prebiotics, synbiotics, fecal microbiota transplantation (FMT), polyphenols, low FODMAP diet and nanotechnology application regulate the gut liver brain axis. Besides, some special treatments targeting gut-liver axis include farnesoid X receptor (FXR) agonists, takeda G protein-coupled receptor 5 (TGR5) agonists, glucagon-like peptide-1 (GLP-1) receptor antagonists and fibroblast growth factor 19 (FGF19) analogs. Targeting gut-brain axis embraces cognitive behavioral therapy (CBT), antidepressants and tryptophan metabolism-related therapies. Targeting liver-brain axis contains epigenetic regulation and Aβ metabolism-related therapies. In the future, a better understanding of gut-liver-brain axis interactions will promote the development of novel preventative strategies and the discovery of precise therapeutic targets in multiple diseases.

Administration of soluble gp130Fc disrupts M-1 macrophage polarization, dendritic cell activation, MDSC expansion and Th-17 induction during experimental cerebral malaria

Regulatory effect of IL-6 on various immune cells plays a crucial role during experimental cerebral malaria pathogenesis. IL-6 neutralization can restore distorted ratios of myeloid dendritic cells and plasmacytoid dendritic cells as well as the balance between Th-17 and T-regulatory cells. IL-6 can also influence immune cells through classical and trans IL-6 signalling pathways. As trans IL-6 signalling is reportedly involved during malaria pathogenesis, we focused on studying the effects of trans IL-6 signalling blockade on various immune cell populations and how they regulate ECM progression. Results show that administration of sgp130Fc recombinant chimera protein lowers the parasitemia, increases the survivability of Plasmodium berghei ANKA infected mice, and restores the distorted ratios of M1/M2 macrophage, mDC/pDC, and Th-17/Treg. IL-6 trans signalling blockade has been found to affect both expansion of myeloid derived suppressor cells (MDSCs) and expression of inflammatory markers on them during Plasmodium berghei ANKA infection indicating that trans IL-6 signalling might regulate various immune cells and their function during ECM. In this work for the first time, we delineate the effect of sgp130Fc administration on influencing the immunological changes within the host secondary lymphoid organ during ECM induced by Plasmodium berghei ANKA infection.

Highlighting the idea of exerkines in the management of cancer patients with cachexia: novel insights and a critical review

BACKGROUND

Exerkines are all peptides, metabolites, and nucleic acids released into the bloodstream during and after physical exercise. Exerkines liberated from skeletal muscle (myokines), the heart (cardiokines), liver (hepatokines), white adipose tissue (adipokines), brown adipose tissue (batokines), and neurons (neurokines) may benefit health and wellbeing. Cancer-related cachexia is a highly prevalent disorder characterized by weight loss with specific skeletal muscle and adipose tissue loss. Many studies have sought to provide exercise strategies for managing cachexia, focusing on musculoskeletal tissue changes. Therefore, understanding the responses of musculoskeletal and other tissue exerkines to acute and chronic exercise may provide novel insight and recommendations for physical training to counteract cancer-related cachexia.

METHODS

For the purpose of conducting this study review, we made efforts to gather relevant studies and thoroughly discuss them to create a comprehensive overview. To achieve this, we conducted searches using appropriate keywords in various databases. Studies that were deemed irrelevant to the current research, not available in English, or lacking full-text access were excluded. Nevertheless, it is important to acknowledge the limited amount of research conducted in this specific field.

RESULTS

In order to obtain a comprehensive understanding of the findings, we prioritized human studies in order to obtain results that closely align with the scope of the present study. However, in instances where human studies were limited or additional analysis was required to draw more robust conclusions, we also incorporated animal studies. Finally, 295 studies, discussed in this review.

CONCLUSION

Our understanding of the underlying physiological mechanisms related to the significance of investigating exerkines in cancer cachexia is currently quite basic. Nonetheless, this demonstrated that resistance and aerobic exercise can contribute to the reduction and control of the disease in individuals with cancer cachexia, as well as in survivors, by inducing changes in exerkines.

IL-6 upregulates the expression of IL-6R through the JAK2/STAT3 signalling pathway to promote progression of hepatocellular carcinoma

The progression of hepatocellular carcinoma (HCC) involves multifactor, multistep interactions. High expression of interleukin-6 receptor (IL-6R) plays an important role in the occurrence and development of tumours, but the regulatory mechanism of IL-6R expression and its function in HCC have not been fully defined. Western blot was used to evaluate the phosphorylation of key kinases in the JAK2/STAT3 pathway and the protein expression levels of related proliferation molecules, migration molecules and apoptotic molecules. The antiapoptosis, migration and proliferation of cells of each group were analysed with JC-1 to judge the cell apoptosis rate, the EdU method to determine the proliferation vitality of the cells, clone formation experiments and Transwell experiments. High expression of IL-6R in cell lines, lower protein levels of the apoptotic molecules c-Caspase7 and c-Caspase3 and higher protein levels of the proliferative molecules p-P70S6K and migration molecules MMP9 and MMP2 were consistent with stronger antiapoptosis, proliferation and migration. Interestingly, IL-6 upregulated the expression of IL-6R by activating the JAK2/STAT3 signalling pathway. Also, the expression of IL-6R protein was downregulated after lentivirus knockdown of STAT3. In nude mice bearing subcutaneous tumours, upregulation of IL-6R expression after activation of the JAK2/STAT3 signalling pathway by IL-6 significantly increased tumour growth. Moreover, the expression of IL-6R protein was downregulated, and the terminal tumour volume was significantly downregulated in the lentiviral STAT3 knockdown group. IL-6 regulated the transcription of IL-6R through the activation of the JAK2/STAT3 signalling pathway.

Study on the Mechanism for SIRT1 during the Process of Exercise Improving Depression

The mechanism behind the onset of depression has been the focus of current research in the neuroscience field. Silent information regulator 1 (SIRT1) is a key player in regulating energy metabolism, and it can regulate depression by mediating the inflammatory response (e.g., nuclear factor-kappa B (NF-κB), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β)), gene expression in the nucleus accumben (NAc) and CA1 region of the hippocampus (e.g., nescient helix-loop-helix2 (NHLH2), monoamine oxidase (MAO-A), and 5-Hydroxyindole-3-acetic acid (5-HIAA)), and neuronal regeneration in the CA3 region of the hippocampus. Exercise is an important means to improve energy metabolism and depression, but it remains to be established how SIRT1 acts during exercise and improves depression. By induction and analysis, SIRT1 can be activated by exercise and then improve the function of the hypothalamic-pituitary-adrenal (HPA) axis by upregulating brain-derived neurotrophic factors (BDNF), inhibit the inflammatory response (suppression of the NF-κB and TNF-α/indoleamine 2,3-dioxygenase (IDO)/5-Hydroxytryptamine (5-HT) pathways), and promote neurogenesis (activation of the insulin-like growth factor1 (IGF-1) and growth-associated protein-43 (GAP-43) pathways, etc.), thereby improving depression. The present review gives a summary and an outlook based on this finding and makes an analysis, which will provide a new rationale and insight for the mechanism by which exercise improves depression.

High Serum Levels of IL-6 Are Associated with Suicide Attempt but Not with High Lethality Suicide Attempts: A Preliminary Case-Control Study

Suicide attempts are an emerging health problem around the world. Increased levels of IL-6 have been associated with suicidal behavior. Therefore, the aims of this study were to evaluate the serum levels of IL-6 in individuals with suicide attempts and a comparison group and to associate the IL-6 levels with the lethality of the suicide attempt. Additionally, we associated the rs2228145 polymorphism of the IL6R gene with suicide attempts or with the IL-6 serum levels. Suicide attempts and their lethality were evaluated using the Columbia Suicide Severity Rating Scale. The serum concentrations of IL-6 were measured by the ELISA technique in individuals with suicide attempts and then compared to a control group. The rs2228145 polymorphism of the IL6R gene was analyzed by real-time polymerase chain reaction. We found elevated serum levels of IL-6 in the suicide attempt group when compared to the control group (F = 10.37, p = 0.002). However, we found no differences of the IL-6 levels between high and low lethality. The IL6R gene polymorphism rs2479409 was not associated with suicide attempts. Our data suggest that IL-6 serum is increased in individuals with suicide attempts.

Roles of Interleukin-6-mediated immunometabolic reprogramming in COVID-19 and other viral infection-associated diseases

Interleukin-6 (IL-6) is a highly pleiotropic glycoprotein factor that can modulate innate and adaptive immunity as well as various aspects of metabolism, including glycolysis, fatty acid oxidation and oxidative phosphorylation. Recently, the expression and release of IL-6 is shown to be significantly increased in numerous diseases related to virus infection, and this increase is positively correlated with the disease severity. Immunity and metabolism are two highly integrated and interdependent systems, the balance between them plays a pivotal role in maintaining body homeostasis. IL-6-elicited inflammatory response is found to be closely associated with metabolic disorder in patients with viral infection. This brief review summarizes the regulatory role of IL-6 in immunometabolic reprogramming among seven viral infection-associated diseases.