Gene of the month: Interleukin 6 (IL-6)

Evaluation of drug resistance for EGFR-TKIs in lung cancer via multicellular lung-on-a-chip

Drug resistance to irreversible epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) is a primary factor affecting their therapeutic efficacy in human non-small cell lung cancer (NSCLC). NSCLC cells can undergo epithelial-mesenchymal transition (EMT) induced by many factors in the tumour microenvironment (TME), which plays a crucial role in tumour drug resistance. In this study, a multicellular lung-on-a-chip that can realise the cell co-culture of the human non-small cell lung cancer cell line HCC827, human foetal lung fibroblasts (HFL-1), and human umbilical vein endothelial cells (HUVECs) is prepared. The TME was simulated on the chip combined with perfusion and other factors, and the drug evaluation of osimertinib was performed to explore the drug resistance mechanism of EGFR-TKIs. In the early stages, a two-dimensional static cell co-culture was achieved by microchip, and the results showed that HFL-1 cells could be transformed into cancer-associated fibroblasts (CAFs), and HCC827 cells could undergo EMT, both of which were mediated by Interleukin-6 (IL-6). Vimentin (VIM) and Alpha Skeletal Muscle Actin (a-SMA) expression of HFL-1 was upregulated, whereas E-cadherin (E-cad) expression of HCC827 was down-regulated. Further, N-cadherin (N-cad) expression of HCC827 was upregulated. In both the static cell co-culture and multicellular lung-on-a-chip, HCC827 cells with CAFs co-culture or IL-6 treatment developed resistance to osimertinib. Further use of the IL-6 antibody inhibitor tocilizumab could reverse EGFR-TKI resistance to a certain extent. Combination therapy with tocilizumab and EGFR-TKIs may provide a novel therapeutic strategy for overcoming EGFR-TKI resistance caused by EMT in NSCLC. Furthermore, the lung-on-a-chip can simulate complex TME and can be used for evaluating tumour resistance and exploring mechanisms, with the potential to become an important tool for personalised diagnosis, treatment, and biomedical research.

The "Heater" of "Cold" Tumors-Blocking IL-6

The resolution of inflammation is not simply the end of the inflammatory response but rather a complex process that involves various cells, inflammatory factors, and specialized proresolving mediators following the occurrence of inflammation. Once inflammation cannot be cleared by the body, malignant tumors may be induced. Among them, IL-6, as an immunosuppressive factor, activates a variety of signal transduction pathways and induces tumorigenesis. Monitoring IL-6 can be used for the diagnosis, efficacy evaluation and prognosis of tumor patients. In terms of treatment, improving the efficacy of targeted and immunotherapy remains a major challenge. Blocking IL-6 and its mediated signaling pathways can regulate the tumor immune microenvironment and enhance immunotherapy responses by activating immune cells. Even transform "cold" tumors that are difficult to respond to immunotherapy into immunogenic "hot" tumors, acting as a "heater" for "cold" tumors, restarting the tumor immune cycle, and reducing immunotherapy-related toxic reactions and drug resistance. In clinical practice, the combined application of IL-6 inhibition with targeted therapy and immunotherapy may produce synergistic results. Nevertheless, additional clinical trials are imperative to further validate the safety and efficacy of this therapeutic approach.

Impaired IL-6-induced JAK-STAT signaling in CD4+ T cells associates with longer treatment duration in giant cell arteritis

INTRODUCTION

The IL-12-IFNγ-Th1 and the IL-6-IL-23-Th17 axes are considered the dominant pathogenic pathways in Giant Cell Arteritis (GCA). Both pathways signal via activation of the downstream JAK/STAT proteins. We hypothesized that phosphorylated STAT (pSTAT) signatures in circulating immune cells may aid to stratify GCA-patients for personalized treatment.

METHODS

To investigate pSTAT expression, PBMCs from treatment-naive GCA-patients (n = 18), infection controls (INF, n = 11) and age-matched healthy controls (HC, n = 15) were stimulated in vitro with IL-6, IL-2, IL-10, IFN-γ, M-CSF or GM-CSF, and stained with CD3, CD4, CD19, CD45RO, pSTAT1, pSTAT3, pSTAT5 antibodies, and analyzed by flow cytometry. Serum IL-6, sIL-6-receptor and gp130 were measured by Luminex. The change in percentages of pSTAT3+CD4+T-cells was evaluated at diagnosis and at 3 months and 1-year of follow-up. Kaplan-Meier analyses was used to asses prognostic accuracy.

RESULTS

Analysis of IL-6 stimulated immune cell subsets revealed a significant decrease in percentages of pSTAT3+CD4+T-cells of GCA-patients and INF-controls compared to HCs. Following patient stratification according to high (median>1.5 pg/mL) and low (median<1.5 pg/mL) IL-6 levels, we observed a reduction in the pSTAT3 response in GCA-patients with high serum IL-6. Percentages of pSTAT3+CD4+T-cells in patients with high serum IL-6 levels at diagnosis normalized after glucocorticoid (GC) treatment. Importantly, we found that patients with low percentages of pSTAT3+CD4+T-cells at baseline require longer GC-treatment.

CONCLUSION

Overall, in GCA, the percentages of in vitro IL-6-induced pSTAT3+CD4+T-cells likely reflect prior in vivo exposure to high IL-6 and may serve as a prognostic marker for GC-treatment duration and may assist improving personalized treatment options in the future.

Identification of viral protein R of human immunodeficiency virus-1 (HIV) and interleukin-6 as risk factors for malignancies in HIV-infected individuals: A cohort study

BACKGROUND

Despite effective antiretroviral therapy, patients with human immunodeficiency virus type-1 (HIV) suffer from a high frequency of malignancies, but related risk factors remain elusive. Here, we focused on blood-circulating viral protein R (Vpr) of HIV, which induces proinflammatory cytokine production and genotoxicity by exogenous functions.

METHODS AND FINDINGS

A total 404 blood samples of HIV patients comprising of 126 patients with malignancies (tumor group) and 278 patients without malignancies (non-tumor group), each of 96 samples was first selected by one-to-one propensity score matching. By a detergent-free enzyme-linked immunosorbent assays (detection limit, 3.9 ng/mL), we detected Vpr at a higher frequency in the matched tumor group (56.3%) than in the matched non-tumor group (39.6%) (P = 0.030), although there was no different distribution of Vpr levels (P = 0.372). We also detected anti-Vpr immunoglobulin (IgG), less frequently in the tumor group compared with the tumor group (22.9% for tumor group vs. 44.8% for non-tumor group, P = 0.002), and the proportion of patients positive for Vpr but negative of anti-Vpr IgG was significantly higher in the tumor group than in the non-tumor group (38.6% vs. 15.6%, respectively, P < 0.001). Additionally, Interleukin-6 (IL-6), the levels of which were high in HIV-1 infected patients (P < 0.001) compared to non-HIV-infected individuals, was significantly higher in advanced cases of tumors (P < 0.001), and IL-6 level was correlated with Vpr in the non-tumor group (P = 0.010). Finally, multivariate logistic regression analysis suggested a positive link of Vpr with tumor occurrence in HIV patients (P = 0.002).

CONCLUSION

Vpr and IL-6 could be risk factors of HIV-1 associated malignancies, and it would be importance to monitor these molecules for well managing people living with HIV-1.

Mathematical model of aging in COVID-19

Background

The aim was examination of the intimamedia thickness of carotid arteries in COVID-19 infection.

Methods

In 50 patients, the thickness of the intimomedial complex (IMT) in the common carotid arteries was measured. The values were compared with the control group in 2006-9. The condition of the lungs was assessed by ultrasound score (It score) (0-42) as mild (0-14) or mediumsevere (15-28) Covid. IMT thickening risk factors and the value of fibrinogen, IL-6 and CRP were recorded. Two IMT prediction models were formed. The socio-epidemiological model predicts the development of IMT based on epidemiological factors. Apart from these factors, the second model also includes the values of the mentioned biomarkers.

Results

It score 20±6, IMT values right: median 0.99 mm, p25=0.89, p75=1.14; left: 1±0.22 mm. Control: IMTright: median 0.7 mm, p25=0.68 mm; p75=0-9 mm; left: median=0.75 mm, p25=0.6 mm, p75=1.0 mm. The group/control difference is highly significant. Epide mio - logical model: logit (IMT)= 4.463+(2.021+value for GEN)+(0.055x AGE value)+(-3.419x RF value)+(-4.447x SM value)+(5.115x HTA value)+(3.56x DM value)+ (22.389x LIP value)+(24.206x CVD value)+(1.449x other value)+(-0.138x It score value)+(0.19xBMI value). Epidemiological-inflammatory model: logit (IMT)=5.204+ (2.545x GEN value)+(0.076x AGE value)+(-6.132x RF value)+(-7.583x SM value)+(8.744x HTA value)+(6.838x DM value)+(25.446x LIP value)+(28.825x CVD value)+ (2.487x other value)+(-0.218xIt score value)+(0.649x BMI value) +(-0.194x fibrinogen value)+(0.894x IL-6 value)+(0.659x CRP value). Values for both models Exp(B)=4.882; P of sample=0.83; logit=-0.19; OR= 23.84; model accuracy for the first model 87% and for the second 88%; Omnibus test of the first model c2=34.324; p=0.000; reliability coefficient -2LogLH=56.854; Omnibus test of the second model c2=39.774; p=0.000; and -2LogLH=51.403.

Conclusions

The ageing of blood vessels in COVID-19 can be predicted.

MVIL6: Accurate identification of IL-6-induced peptides using multi-view feature learning

Interleukin-6 (IL-6) is a potential therapeutic target for many diseases, and it is of great significance in accurately predicting IL-6-induced peptides for IL-6 research. However, the cost of traditional wet experiments to detect IL-6-induced peptides is huge, and the discovery and design of peptides by computer before the experimental stage have become a promising technology. In this study, we developed a deep learning model called MVIL6 for predicting IL-6-inducing peptides. Comparative results demonstrated the outstanding performance and robustness of MVIL6. Specifically, we employ a pre-trained protein language model MG-BERT and the Transformer model to process two different sequence-based descriptors and integrate them with a fusion module to improve the prediction performance. The ablation experiment demonstrated the effectiveness of our fusion strategy for the two models. In addition, to provide good interpretability of our model, we explored and visualized the amino acids considered important for IL-6-induced peptide prediction by our model. Finally, a case study presented using MVIL6 to predict IL-6-induced peptides in the SARS-CoV-2 spike protein shows that MVIL6 achieves higher performance than existing methods and can be useful for identifying potential IL-6-induced peptides in viral proteins.

Analysis of the Effects of IL-6 -572 C/G, CRP -757 A/G, and CRP -717 T/C Gene Polymorphisms; IL-6 Levels; and CRP Levels on Chronic Periodontitis in Coronary Artery Disease in Indonesia

Interleukin 6 (IL-6) and C-Reactive Protein (CRP) play an important role in chronic periodontitis with coronary artery disease (CAD). Genetic factors can affect a person's risk of CAD, which affects one-third of the population. This study investigated the role of IL-6 -572 C/G, CRP -757 A/G, and CRP -717 T/C gene polymorphisms. IL-6 and CRP levels on the severity of periodontitis in CAD in Indonesia were also evaluated. This case-control study was conducted with mild and moderate-severe chronic periodontitis groups. A path analysis test was conducted with Smart PLS with a 95% confidence interval to determine the significant variable for chronic periodontitis. Our study revealed that the effects of IL-6 -572 C/G, CRP -757 A/G, and CRP -717 T/C gene polymorphisms on IL-6 levels and CRP levels were not significant. IL-6 and CRP levels were not significantly different between the two groups. We found that IL-6 levels had a significant effect on CRP levels in periodontitis patients with CAD (path coefficient 0.322, p = 0.003). IL-6 -572 C/G, CRP -757 A/G, and CRP -717 T/C gene polymorphisms had no effect on the severity of chronic periodontitis in CAD patients in the Indonesian population. We also observed no apparent effects of the influence of gene polymorphisms in IL-6 -572 C/G, CRP -757 A/G, and CRP -717 T/C genes. Although the IL-6 and CRP levels were not significantly different between the two groups, IL-6 levels affected CRP levels in periodontitis patients with CAD.

Biomarkers in alopecia Areata: A systematic review and meta-analysis

BACKGROUND

Alopecia areata (AA) is an autoimmune non-scarring alopecia that affects the scalp or any hair-bearing areas in the body. The pathophysiology of AA is complex, but Th1, Th2, and Th17 cytokines dysregulation, as well as chemokines, immunoglobulins and other biomarkers have been shown to play a role in the pathogenesis of the disease.

OBJECTIVE

To conduct a systematic review and Meta-analysis to identify biomarkers that reflect AA activity and severity that could be used to better assess disease activity and response in both trials and clinical practice.

METHODS

A literature search was conducted using the PUBMED, EMBASE and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) from inception to December 2021. Articles reporting on associations between AA and serum clinical biomarkers (cytokines, chemokines, antibodies, immunoglobulins, and others) were included. Serum biomarkers were identified in patients with AA and were correlated with disease severity and patient characteristics (ex. age, sex, comorbidities). The quality of the studies was assessed using the National Heart, Lung, and Blood Institute's Quality Assessment Tool for Case-Control Studies. Meta-analysis pooling of the standardized mean differences (SMD) by the method of Cohen using the common-effect inverse-variance model was performed. For the Meta-analysis, data was pulled for all the markers with a minimum of 4 studies with means and standard deviations. Analysis of data reported as Median with range or inter-quartile range (IQR) revealed that the data was too skewed to recommend calculation and use of mean with standard deviation (SD). If the data were not skewed, mean and SD were calculated.

RESULTS

One thousand seven hundred fourteen studies were screened, with 91 included, reporting on a total of 52 biomarkers. Meta-analyses revealed pooled SMD that were significant for interleukin 6 (IL6), C-reactive protein (CRP) and vitamin D.

CONCLUSIONS

Serum IL6 and CRP levels are significantly increased in patients with AA compared to healthy age and sex matched controls. Conversely, serum vitamn D levels are significantly decreased in patients with AA compared to healthy age and sex matched controls. This data has the potenail to influence the clinical guidelines for the diagnostic workup of AA to include testing the serum levels of CRP and vitamin D.

The effect of citrate in cardiovascular system and clot circuit in critically ill patients requiring continuous renal replacement therapy

We aimed to evaluate the impact of citrate on hemodynamic responses and secondary outcomes, including the filter life span, metabolic complications, and levels of inflammatory cytokines, in critically ill patients who required CRRT compared with those who underwent the heparin-free method. This prospective, multicenter, open-label randomized trial compared regional citrate anticoagulation (RCA) with a heparin-free protocol in severe acute kidney injury (AKI) patients who received continuous venovenous hemodiafiltration (CVVHDF) in the postdilution mode. We measured hemodynamic changes using the FloTrac Sensor/EV1000™ Clinical Platform at certain time points after starting CRRT (0, 6, 12, 24, 48, and 72 h.). The levels of inflammatory cytokines (IL-1β, IL-6, IL-8, IL-10 and TNF-ɑ) were measured on days 1 and 3. Forty-one patients were recruited and randomized into the heparin (n = 20) and citrate groups (n = 21). The cardiac performances were not significantly different between the 2 groups at any time point. The inflammatory cytokines declined similarly in both treatment arms. The maximum filter survival time was insignificantly longer in the RCA group than in the heparin-free group (44.64 ± 26.56 h. vs p = 0.693 in citrate and heparin free group). No serious side effects were observed for either treatment arm, even in the group of liver dysfunction patients. RCA did not affect hemodynamic changes during CRRT. Inflammatory cytokines decreased similarly in both treatment arms.The filter life span was longer in the citrate group. RCA is a valid alternative to traditional anticoagulation and results in stable hemodynamic parameters.

The role of IL-6/JAK2/STAT3 signaling pathway in cancers

Interleukin-6 (IL-6) is a pleiotropic cytokine involved in immune regulation. It can activate janus kinase 2 (JAK2)-signal transducer and activator of transcription 3 (STAT3) signaling pathway. As one of the important signal transduction pathways in cells, JAK2/STAT3 signaling pathway plays a critical role in cell proliferation and differentiation by affecting the activation state of downstream effector molecules. The activation of JAK2/STAT3 signaling pathway is involved in tumorigenesis and development. It contributes to the formation of tumor inflammatory microenvironment and is closely related to the occurrence and development of many human tumors. This article focuses on the relationship between IL-6/JAK2/STAT3 signaling pathway and liver cancer, breast cancer, colorectal cancer, gastric cancer, lung cancer, pancreatic cancer and ovarian cancer, hoping to provide references for the research of cancer treatment targeting key molecules in IL-6/JAK2/STAT3 signaling pathway.

Expression analysis of cytokines IL-5, IL-6, IL-8, IL-17 and VEGF in breast cancer patients

OBJECTIVE

To investigate the relationship between changes in peripheral blood vascular endothelial growth factor (VEGF), interleukin-5 (IL-5), interleukin-6 (IL-6), interleukin-8 (IL-8) and interleukin-17 (IL-17) concentrations in breast cancer patients and their significance and clinical value in breast cancer staging and invasive metastasis.

METHODS

From September 2021 to April 2022, 60 breast cancer patients from Chongqing Medical University Hospital No. 2022 were enrolled in the breast breast cancer surgery group, while 30 patients with benign breast disease were enrolled in the control group during the same period. Venous blood samples were collected at admission and 1 week after surgery to determine the expression of these factors in serum. Statistical methods such as Wilcoxon test and Spearman correlation analysis were used to analyze the relationship between the above factors and the clinicopathological characteristics of the patients.

RESULTS

By analyzing data from patients with benign and malignant breast tumors, an association was found with serum levels of IL-6, IL-17 and VEGF. Their respective areas under the operating characteristic curve were 0.649, 0.734 and 0.656 (P < 0.05). There were significant differences in the cytokine expression levels of IL-17 and VEGF in different molecular typing (P values were 0.008 and 0.040, respectively). The expression levels of IL-17 and VEGF were higher in HER-2 receptor-positive and triple-negative patients than in hormone receptor-positive patients (P < 0.05). Also, no significant correlation was found between the various cytokines mentioned in the article and breast cancer lymph node metastasis and Tumor Node Metastasis stage (TNM stage). In addition, in the breast cancer surgery group, postoperative VEGF levels were lower (P < 0.05) and IL-6 levels were higher (P < 0.05) compared to preoperative levels.

CONCLUSIONS

Serum IL-6, IL-17, and VEGF are strongly associated with breast cancer development and can be used as a reference indicators for breast cancer diagnosis. In addition, post-operative VEGF levels decreases and IL-6 levels increases compared to pre-operative levels, which can also be used as an a postoperative follow-up indicator. In contrast, IL-5 and IL-8 have not found to be significantly associated with breast cancer patients in this study, which requires further study.

Mechanisms of Xiong-Pi-Fang in treating coronary heart disease associated with depression: A systematic pharmacology strategy and in vivo pharmacological validation

BACKGROUND

Coronary heart disease (CHD) and depression are very common and often co-existing disorders. Xiong-Pi-Fang (XPF), a therapeutic classical traditional Chinese medicine (TCM) formula, has shown satisfactory efficacy in treating CHD associated with depression. However, its mechanism of action is still unknown.

PURPOSE

To employ a systematic pharmacology approach for identifying the action mechanisms of XPF in treating CHD associated with depression.

METHODS

We used a systematic pharmacology approach to identify the potential active mechanisms of XPF in treating CHD with depression. Potential active compounds in XPF and the diseases targets were screened using relevant databases to build corresponding pathways, following the experiments that were conducted to confirm whether the presumptive results of systemic pharmacology were correct.

RESULTS

Network pharmacology predicted 42 key targets and 20 signaling pathways involved in XPF-mediated treatment, with IL-6/JAK2/STAT3/HIF-1α/VEGF-A pathway significantly affected. The common influences were hypothalamic-pituitary-adrenal axis (HPA axis) and glucocorticoid signaling, validated through chronic unexpected mild stress (CUMS) with isoprenaline (ISO) for inducing CHD within the depression model in rats. In addition, XPF intake reduced depressive-like behaviors and improved ECG ischemic changes. Furthermore, XPF exerted some anti-inflammatory effects by inhibiting the interleukin-6 (IL-6) induced phosphorylation of janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3), ultimately downregulating hypoxia-inducible factor 1-α (HIF-1α) and vascular endothelial growth factor-A (VEGF-A) activation. The dysfunctional HPA axis feedback loop was also regulated, which enhanced the glucocorticoid receptor (GR) expression. In contrast, it improved glucocorticoid resistance by reducing the mineralocorticoid receptor expression.

CONCLUSIONS

Suppressing IL-6 release and maintaining the HPA feedback loop balance could be the primary mechanism of XPF against CHD with depression. The significance of the IL-6 and HPA axis identified indicates their potential as essential targets for CHD therapy with depression.

MiR-99a-5p Constrains Epithelial-Mesenchymal Transition of Cervical Squamous Cell Carcinoma Via Targeting CDC25A/IL6

MiR-99a-5p participates in processes and pathogenesis of varying diseases. However, the molecular mechanism of miR-99a-5p in human cervical squamous cell carcinoma (CSCC) remains unclear. Here, we found that miR-99a-5p was lowly expressed in CSCC cells and negatively associated with overall survival. In addition, cellular experiments including CCK8, wound healing, Transwell and flow cytometry assays disclosed that transfection of miR-99a-5p mimic could suppress the cell activity, cell migratory, and invasive abilities, and promote cell apoptosis, thus inhibiting the tumor progression of CSCC cells. Luciferase reporter gene assay indicated that miR-99a-5p targeted 3'-UTR of CDC25A. Also, enforced CDC25A level rescued the impact of miR-99a-5p on CSCC progression. Silencing CDC25A could restrain the mRNA and protein levels of IL-6 in CSCC. CDC25A overexpression or IL-6 treatment could attenuate inhibiting impact of miR-99a-5p overexpression on epithelial-mesenchymal transition (EMT). These findings suggested that miR-99a-5p may play an anti-tumor role in tumor metastasis by targeting CDC25A/IL6 to hamper EMT process, which revealed a novel molecular mechanism in CSCC.

Research models of sulfur mustard- and nitrogen mustard-induced ocular injuries and potential therapeutics

Sulfur mustard (SM) is a notorious, bifunctional alkylating vesicant that was first used in warfare during World War I in 1917 and since then has been deployed in numerous skirmishes with its most recent documented use being during the Middle Eastern conflicts. Apart from its use in combat and terrorist activities, continual threat of accidental exposure from old stockpiles and improperly discarded munitions is ever present, especially to the innocent and unassuming civilian populations. SM can cause devastating injuries, depending on the dosage of SM exposure, route of exposure, as well as the physiological conditions of the individuals exposed. The most common routes of exposure are ocular, dermal, and exposure to the lungs and respiratory tissues through inhalation. Eyes are the most susceptible organ to SM-induced toxicities owing to their high moisture content and rapidly dividing cells. Additionally, ocular injury causes the most expeditious disablement of individuals even upon whole-body exposures. Therefore, it is imperative to understand the mechanisms underlying SM-induced ocular toxicity and design therapeutic interventions to prevent/mitigate ocular injuries. Ocular SM exposure may cause a wide range of symptoms such as inflammation, lacrimation, itching, dryness, photophobia, edema of the cornea/sclera/retina/iris, conjunctivitis, degradation of the corneal layer, fusion of two or more ocular layers, neovascularization, fibrosis, and temporary or permanent structural damage to one or more ocular layers. These symptoms may lead to vision impairments, resulting in partial or complete blindness that may be permanent. The highly toxic and exceedingly notorious nature of SM makes it a highly regulated chemical, requiring very expensive licensing, security, and safety requirements; thus, the more easily accessible analogue, nitrogen mustard (NM) that mimics SM-induced toxicity and injuries is employed in plethora of studies conducted in different animal models and culture systems. This review provides a comprehensive account of the injuries and symptoms that occur upon ocular SM exposures in human patients as well as studies in animal (in vivo, ex vivo) and cell (in vitro) models of SM and NM ocular exposures. Special emphasis has been laid on highlighting the strengths and lacunae in the research as well as the possible unexplored avenues of mechanisms underlying mustard-induced ocular injury that can be explored in future research endeavors. Furthermore, development of therapeutic interventions and targets of interest in the ocular system exposed to SM and NM, based on studies in human patients as well as in vivo, ex vivo, and in vitro models has been discussed in great depth, providing a valuable knowledge database to delineate pathways associated with vesicant-induced toxicity, and strategies/diagnostic tools against SM-induced toxicity.

Discovery of Se-containing flavone in Se-enriched green tea and the potential application value in the immune regulation

Selenium (Se)-enriched green tea has been recognized as a possible source of supplemental Se, while the structural and physiological activities of Se-containing flavone are still unclear. In this study, a Se-containing flavone was isolated from Se-enriched green tea by high-speed counter-current chromatography (HSCCC) and characterized through UHPLC-Q-Orbitrap, FT-IR and NMR. Results proved that HSeO₃^- can be combined with the alcohol hydroxyl of 2-phenylchromone in flavone and the content of Se-containing flavone in tea was 15690.4 μg L^-1. Additionally, Se-containing flavone can effectively inhibit the production of nitric oxide (NO), and downregulate expression of TNF-α and IL-6. Compared with regular flavone extracted from green tea (43.24 pg mL^-1), release of IL-10 was higher in Se-containing flavone group (53.37 pg mL^-1), indicating that Se-containing flavone played an important role in the process of severe inflammatory injury. The results indicated that Se-containing flavone was an attractive natural ingredient for developing novel functional foods.

In silico screening for oligopeptides useful as capture and reporting probes for interleukin-6 biosensing

IL-6 is an important interleukin associated with inflammation and several diseases such as cancer. Evaluation of its levels in human blood sera is a critical step for an accurate diagnosis of the diseases. Our goal is to design peptides that can selectively bind in different poses with good affinities to IL-6. For this purpose, we started from the crystal structures of different IL-6/protein complexes available in the Protein Data Bank (PDB) to select short peptides in the interaction zones, in which we intentionally introduced point mutations to increase their stability and affinity. To examine their usefulness as capture and reporting probes for the IL-6 biosensing, the five peptides and their interaction with IL-6 were studied in saline aqueous solution. Molecular docking, MD, and MM-PBSA were used to investigate the affinity and stability of these complexes. The conformational changes, the distance between the mass centers, the gyration radii, and the numbers of hydrogen bonds were analyzed to select the most suitable candidates. Three peptides, namely CTE17, CAY15 and CSE25, have the highest affinities presenting significant numbers of residues that have contact frequencies greater than 50% of simulation run time and are the most promising candidates. CTE17 and CSE25 showed they can form a stable sandwich with the target protein. For sake of comparison, we examined the previously known peptides (FND20, INL19 and CEK17) having affinity to IL-6 and the affinity of the lead i.e. CSE25 to two other interleukin family members (IL-4 and to IL-10).

In silico design by docking and molecular dynamics of short peptides that can selectively recognize IL-6 for biosensing purposes.

Procalcitonin, Interleukin-6 and C-reactive Protein Levels Predict Renal Adverse Outcomes and Mortality in Patients with Acute Type A Aortic Dissection

Background

Acute type A aortic coarctation (AAAD) is a highly deadly and serious life-threatening disease. The purpose of this study was to estimate the predictive value of peak procalcitonin, interleukin-6, and C-reactive protein levels on adverse renal outcomes and mortality in patients undergoing surgery for AAAD.

Methods

Perioperative peak PCT, CRP, and IL-6 levels were retrospectively collected in 331 patients hospitalized with AAAD from 2009 to 2021. The primary endpoints were AKI stage 2–3 and mortality. The receiver operating characteristic (ROC) curves were used to compare the predictive values of peak PCT, CRP, and IL-6 for different clinical outcomes. Multivariable logistic regression analysis was used to find risk factors for AKI and 30-day mortality.

Results

The incidence of AKI stage 2–3 following AAAD was 50.8% (168/331). The 30-day and overall mortality were significantly greater in the AKI 2–3 group than in the AKI 0–1 group (P = 0.000). ROC curve analysis showed that peak PCT, with an area under the ROC curve (AUC) of 0.712, was a more accurate predictor of adverse renal outcomes than peak IL-6 and CRP. Multivariable logistic regression analysis revealed that PCT > 0.39 ng/mL was an independent risk factor for AKI stage 2–3. Peak IL-6 > 259 pg/mL was found to be an independent risk factor for 30-day mortality.

Conclusion

In patients with surgery for AAAD, peak PCT provides a well-predictive indicator of AKI stage 2–3 and peak IL-6 indicates a favorable predictor of 30-day mortality.

Proinflammatory Cytokines (IL-1, -6, -8, -15, -17, -18, -23, TNF-α) Single Nucleotide Polymorphisms in Rheumatoid Arthritis-A Literature Review

Conducted studies highlight that a mixture of genetic and environmental factors is responsible for rheumatoid arthritis (RA) development. This study aimed to analyze the available literature for the relationship between, on the one hand, single-nucleotide polymorphisms (SNPs) in the proinflammatory cytokines genes interleukin-1 (IL-1), -6, -8, -15, -17, -18, and -23, and tumor necrosis factor-alpha (TNF-α), and on the other hand, RA susceptibility, severity, and patients' response to applied treatment. The PubMed database was searched for sources. Preference was given to articles which were published within the past 20 years. Data indicate that the relationship between selected SNPs in proinflammatory cytokines genes and susceptibility to developing RA is inconclusive, and it depends on the ethnicity of the population. Although the allelic and genotypic frequencies of many SNPs in proinflammatory cytokines genes analyzed did not differ between RA patients and healthy controls, deeper analysis showed that these polymorphisms have a relationship with clinicopathological features of RA. SNPs in proinflammatory cytokines genes also "modify patients' response" to applied treatment. Further studies, on larger cohorts of subjects and in different populations, should be conducted to elucidate the role of SNPs in IL-1, -6, -8, -15, -17, -18, and -23, and TNF-α genes in RA patients.

Classical Signaling and Trans-Signaling Pathways Stimulated by Megalobrama amblycephala IL-6 and IL-6R

Interleukin-6 (IL-6) is a multipotent cytokine. IL-6 plays a dual role in inflammation through both classical signaling (IL-6 binds membrane IL-6 receptor/IL-6R) and trans-signaling (IL-6 binds soluble IL-6R). However, the regulation of IL-6 activity, especially the regulation of signaling pathways and downstream genes mediated by IL-6 trans-signaling, remains largely unclear in teleost. Grass carp (Ctenopharyngodon idellus) hepatic (L8824) cells, kidney (CIK) cells, and primary hepatocytes were used as test models in this study. First, the biological activity of recombinant blunt snout bream (Megalobrama amblycephala) IL-6 (rmaIL-6) and sIL-6R (rmasIL-6R) was verified by quantitative PCR (qPCR) and western blot. The western blot results showed that rmaIL-6 significantly upregulated signal transducer and activator of transcription 3 (STAT3) phosphorylation in L8824 cells and primary hepatocytes, while rmaIL-6 in combination with rmasIL-6R (rmaIL-6+rmasIL-6R) significantly upregulated STAT3 phosphorylation in all types of cells. Furthermore, maIL-6 and maIL-6+rmasIL-6R could only induce extracellular-signal-regulated kinase 1/2 (ERK1/2) phosphorylation in L8824 cells and CIK cells, respectively. Therefore, IL-6 mainly acts by activating the janus kinase (JAK)/STAT3 pathway rather than the mitogen-activated protein kinase (MEK)/ERK pathway. Finally, the activation of the JAK2/STAT3 pathway was shown to be essential for the generation of socs3a and socs3b induced by IL-6 trans-signaling after treatment by JAK2/STAT3 pathway inhibitors (c188-9 and TG101348). These findings provide functional insights into IL-6 classical signaling and trans-signaling regulatory mechanisms in teleost, enriching our knowledge of fish immunology.

DEC1 negatively regulates CYP2B6 expression by binding to the CYP2B6 promoter region ascribed to IL-6-induced downregulation of CYP2B6 expression in HeLa cells

The cytochrome P450 superfamily (CYPs) is a group of metabolic enzymes involved in drug biotransformation/metabolism. It is the most important drug metabolic enzyme; however, its mechanism of action remains unclear.We investigated the expression of CYP2B6 in HeLa cells induced by interleukin-6 (IL-6) and explored the relationship between differentially expressed chondrocytes 1 (DEC1) and CYP2B6 via luciferase reporter, chromatin immunoprecipitation (ChIP) and ELISA assays.We observed the expression of CYP2B6 in HeLa cells exhibited a time-dependent decrease under the effect of IL-6, and the expression of CYP2B6 down-regulated by IL-6was negatively correlated with DEC1. After overexpression or knockdown of DEC1 in HeLa cells, the expression of CYP2B6 decreased or increased. The luciferase reporter assay and ChIP assay confirmed that DEC1 inhibited the expression of CYP2B6 by binding to the CYP2B6 promoter. ELISA results showed that high expression of DEC1 or low expression of CYP2B6 can promote the secretion of IL-6 in HeLa cells, and the secreted IL-6 can continually downregulate the expression of CYP2B6 in HeLa cells.Our results indicate that DEC1/CYP2B6 pathway in the inflammatory environment of tumours, and this provides a small amount of theoretical basis for the study of genes encoding drug-metabolising enzymes.

Hyperthermia alters interleukin-6 production in response to lipopolysaccharide via endoplasmic reticulum stress in bovine endometrial cells

In the postpartum period, cows experience the uterine bacterial infection and develop the endometritis. To eliminate bacteria and recover from endometritis, endometrial epithelial and stromal cells secrete the cytokine and chemokine, such as interleukin 6 (IL-6), IL-8, and monocyte chemotactic protein 1 (MCP1), to recruit immune cells. Moreover, the symptom of endometritis is prolonged in summer and we have recently indicated that hyperthermia suppresses and enhances the IL-6 production in response to lipopolysaccharide (LPS) challenge in endometrial epithelial and stromal cells, respectively. However, the mechanisms for the opposite reaction of IL-6 secretion in response to LPS challenge in both types of endometrial cells under hyperthermia conditions were still unclear. To reveal these mechanisms, both types of endometrial cells were cultured with LPS under the control (38.5°C) or hyperthermia (40.5°C) conditions and comprehensively analyzed differential gene expressions of them by RNA-seq. In addition, based on these results, we examined the effect of endoplasmic reticulum (ER) stress on the IL-6 production in both types of endometrial cells cultured with LPS under hyperthermia conditions. In comprehensive analysis, hyperthermia induced the ER stress in the endometrial stromal cells but not in the endometrial epithelial cells. Actually, we confirmed that hyperthermia increased the gene expression of BiP, ATF4, and sXBP1 and protein expression of BiP and phosphorylated inositol requiring 1, ER stress marker, in the endometrial stromal cells but not in the endometrial epithelial cells. Moreover, in the endometrial stromal cells exposed to LPS, activation and inhibition of ER stress enhanced the IL-6 production under control conditions and suppressed it under hyperthermia conditions, respectively. In this study, we could uncover the one of causes for the disruption of IL-6 production in response to LPS challenge in the endometrial cells under hyperthermia conditions. This finding might be a clue for the improvement of the symptom of endometritis in cows during summer.

MicroRNA-214 promotes alveolarization in neonatal rat models of bronchopulmonary dysplasia via the PlGF-dependent STAT3 pathway

BACKGROUND

Recently, the role of several microRNAs (miRNAs or miRs) in pulmonary diseases has been described. The molecular mechanisms by which miR-214 is possibly implicated in bronchopulmonary dysplasia (BPD) have not yet been addressed. Hence, this study aimed to investigate a putative role of miR-214 in alveolarization among preterm neonates with BPD.

METHODS

Microarray-based gene expression profiling data from BPD was employed to identify differentially expressed genes. A BPD neonatal rat model was induced by hyperoxia. Pulmonary epithelial cells were isolated from rats and exposed to hyperoxia to establish cell injury models. Gain- and loss-of-function experiments were performed in BPD neonatal rats and hyperoxic pulmonary epithelial cells. MiR-214 and PlGF expression in BPD neonatal rats, and eNOS, Bcl-2, c-myc, Survivin, α-SMA and E-cadherin expression in hyperoxic pulmonary epithelial cells were measured using RT-qPCR and Western blot analysis. The interaction between PlGF and miR-214 was identified using dual luciferase reporter gene and RIP assays. IL-1β, TNF-a, IL-6, ICAM-1 and Flt-1 expression in the rat models was measured using ELISA.

RESULTS

The lung tissues of neonatal rats with BPD showed decreased miR-214 expression with elevated PlGF expression. PlGF was found to be a target of miR-214, whereby miR-214 downregulated PlGF to inactivate the STAT3 pathway. miR-214 overexpression or PlGF silencing decreased the apoptosis of hyperoxic pulmonary epithelial cells in vitro and restored alveolarization in BPD neonatal rats.

CONCLUSION

Overall, the results demonstrated that miR-214 could facilitate alveolarization in preterm neonates with BPD by suppressing the PlGF-dependent STAT3 pathway.

Osteopontin enhances the migration of lung fibroblasts via upregulation of interleukin-6 through the extracellular signal-regulated kinase (ERK) pathway

Fibrosis is a phenomenon in which parenchyma is replaced with fibrous tissue. Persistent inflammation accompanied by dysregulation of cytokine production and repeated cycles of inflammation-associated tissue-repair induces fibrosis in various organs including the liver, lung, and kidney. In idiopathic pulmonary fibrosis, production of interleukin (IL)-6 and osteopontin (OPN) are dysregulated. Fibrosis leads to qualitative rather than quantitative changes of fibroblasts at the sites of tissue repair, and this leads to enlargement of fibrotic foci. These fibroblasts are immunohistochemically positive for OPN; however, the effect of overexpressed OPN in fibroblasts is not fully understood yet. In this study, we investigated the effect of OPN on IL-6 secretion and on migration and proliferation of fibroblasts. Lung fibroblasts overexpressing exogenous OPN showed that OPN was linked to the enhancement of cell migration through increased IL-6 secretion via the extracellular signal-regulated kinase (ERK) pathway. These results suggest that OPN may exert its pro-fibrotic functions, such as enhancement of fibroblasts migration by cooperating with chemoattractant IL-6, and may be involved in enlargement of fibrotic foci.

The Postnatal Leptin Surge Supports Immune Cell Function in Rats

Background: Leptin plays an important role in the regulation of the immune response. There is a physiological surge of leptin in rodents during the neonatal period, which has mainly been studied in the context of brain development. However, little is known about the effects of this neonatal leptin surge on immunity. Therefore, we investigated whether blocking this leptin surge could affect several immune functions.Methods: Male and female rats were injected subcutaneously with 5 mg/Kg/day of rat pegylated super leptin antagonist during the neonatal period (PND5-9). On the peripubertal period, relevant functions as well as cytokine release by spleen leukocytes were studied in these animals.Results: The results showed that the animals significantly display an impaired anti-tumor NK activity and chemotactic and proliferation capacity of lymphocytes in response to mitogens. In addition, several cytokine concentrations, released under mitogen-stimulated conditions, were also altered.Conclusion: In conclusion, the neonatal leptin surge seems to be involved in the establishment of an adequate immune response and cytokine profile, which are crucial for the maintenance of a healthy life.

Computer-aided prediction and design of IL-6 inducing peptides: IL-6 plays a crucial role in COVID-19

Interleukin 6 (IL-6) is a pro-inflammatory cytokine that stimulates acute phase responses, hematopoiesis and specific immune reactions. Recently, it was found that the IL-6 plays a vital role in the progression of COVID-19, which is responsible for the high mortality rate. In order to facilitate the scientific community to fight against COVID-19, we have developed a method for predicting IL-6 inducing peptides/epitopes. The models were trained and tested on experimentally validated 365 IL-6 inducing and 2991 non-inducing peptides extracted from the immune epitope database. Initially, 9149 features of each peptide were computed using Pfeature, which were reduced to 186 features using the SVC-L1 technique. These features were ranked based on their classification ability, and the top 10 features were used for developing prediction models. A wide range of machine learning techniques has been deployed to develop models. Random Forest-based model achieves a maximum AUROC of 0.84 and 0.83 on training and independent validation dataset, respectively. We have also identified IL-6 inducing peptides in different proteins of SARS-CoV-2, using our best models to design vaccine against COVID-19. A web server named as IL-6Pred and a standalone package has been developed for predicting, designing and screening of IL-6 inducing peptides (https://webs.iiitd.edu.in/raghava/il6pred/).

Temperature Plays an Essential Regulatory Role in the Tumor Immune Microenvironment

In recent years, emerging immunotherapy has been included in various malignant tumor treatment standards. Temperature has been considered to affect different pathophysiological reactions such as inflammation and cancer for a long time. However, in tumor immunology research, temperature is still rarely considered a significant variable. In this review, we discuss the effects of room temperature, body temperature, and the local tumor temperature on the tumor immune microenvironment from multiple levels and perspectives, and we discuss changes in the body's local and whole-body temperature under tumor conditions. We analyze the current use of ablation treatment-the reason for the opposite immune effect. We should pay more attention to the therapeutic potential of temperature and create a better antitumor microenvironment that can be combined with immunotherapy.

Improved Spatial Memory And Neuroinflammatory Profile Changes in Aged Rats Submitted to Photobiomodulation Therapy

Recent evidences have shown the therapeutic potential of transcranial photobiomodulation on traumatic brain injury and Alzheimer's disease. Despite the promising benefits in the brain, little is known about the laser's effects in the absence of pathological conditions. We submitted young (4 months old) and aged (20 months old) rats to transcranial low-level laser and evaluated their exploratory activity and habituation in open field, anxiety in elevated plus maze, spatial memory in Barnes maze, and aversive memory in a step-down inhibitory avoidance task. Additionally, the levels of a panel of inflammatory cytokines and chemokines were quantified in two different brain regions: the cerebral cortex and the hippocampus. Young and aged rats submitted to transcranial laser exhibited better cognitive performance in Barnes maze than did control rats. Transcranial laser therapy decreased cortical levels of GM-CSF, IL-10, MCP-1, LIX, and TNFα in young rats and IL-5 in aged rats. High levels of IL-6, IL-10, and TNF-alpha were found in the cerebral cortex of aged rats submitted to transcranial laser. In the hippocampus, a decrease in IP-10 and fractalkine levels was observed in the aged rats from the laser group when compared to the aged rats from the control group. Our data indicate that transcranial photobiomodulation improves spatial learning and memory and alters the neuroinflammatory profile of young and aged rats' brains.

Therapeutic measures for sulfur mustard-induced ocular injury

The use of sulfur mustard (SM) in global terrorism is still a relevant threat to both civilian population and military personnel. Casualties exposed to SM may present mild, moderate or severe acute ocular lesions followed by a complete ocular resolution, chronic lesions or re-emerged ocular pathologies after a latent period. Current treatment for SM-induced ocular injury is based mainly on the clinical manifestation at the different stages of the injury and includes pharmaceutical and surgical interventions. These therapeutic measures are beneficial but not sufficient, and the ocular injury remains a continuous challenge for medical professionals. This review focuses on treatment experience carried out in humans and studied in animal models, for both SM-induced ocular acute injury and late pathology. In general, therapeutic measures are based on clinical features of the ocular injury or on the involvement of specific factors during the ocular injury that point out towards potential treatments. Anti-inflammatory treatments and limbal stem cell transplantation techniques were developed based on the clinical manifestation of the ocular injury. Optional therapies for impaired corneal innervation and endothelium are suggested for future research. Additionally, studies on potential treatments with anti-matrix metalloproteinase (MMP), anti-vascular endothelial growth factor (VEGF) and anti-IL-6 agents are discussed. Consequently, future studies may reveal the potential of additional pharmacological and biological treatments or advanced cellular and molecular biology methods to serve as novel therapeutic measures and techniques for this complicated ocular injury.

Endothelial activation and dysfunction in COVID-19: from basic mechanisms to potential therapeutic approaches

On 12 March 2020, the outbreak of coronavirus disease 2019 (COVID-19) was declared a pandemic by the World Health Organization. As of 4 August 2020, more than 18 million confirmed infections had been reported globally. Most patients have mild symptoms, but some patients develop respiratory failure which is the leading cause of death among COVID-19 patients. Endothelial cells with high levels of angiotensin-converting enzyme 2 expression are major participants and regulators of inflammatory reactions and coagulation. Accumulating evidence suggests that endothelial activation and dysfunction participate in COVID-19 pathogenesis by altering the integrity of vessel barrier, promoting pro-coagulative state, inducing endothelial inflammation, and even mediating leukocyte infiltration. This review describes the proposed cellular and molecular mechanisms of endothelial activation and dysfunction during COVID-19 emphasizing the principal mediators and therapeutic implications.

Targeted treatment of alcoholic liver disease based on inflammatory signalling pathways

Targeted therapy is an emerging treatment strategy for alcoholic liver disease (ALD). Inflammation plays an important role in the occurrence and development of ALD, and is a key choice for its targeted treatment, and anti-inflammatory treatment has been considered beneficial for liver disease. Surprisingly, immune checkpoint inhibitors have become important therapeutic agents for hepatocellular carcinoma (HCC). Moreover, studies have shown that the combination of inflammatory molecule inhibitors and immune checkpoint inhibitors can exert better effects than either alone in mouse models of HCC. This review discusses the mechanism of hepatic ethanol metabolism and the conditions under which inflammation occurs. In addition, we focus on the potential molecular targets in inflammatory signalling pathways and summarize the potential targeted inhibitors and immune checkpoint inhibitors, providing a theoretical basis for the targeted treatment of ALD and the development of new combination therapy strategies for HCC.

Curcumin inhibits lipopolysaccharide and lipoteichoic acid-induced expression of proinflammatory cytokines and production of PGE2 in the primary bubaline endometrial stromal cells

Infection of the uterus with Gram-positive Trueperella pyogenes and Gram-negative Escherichia coli is a common cause of postpartum endometritis in the cattle and buffalo and the condition is treated with antimicrobial drugs. The presence of drug residues in the milk and development of resistant bacteria necessitate the evaluation of alternate therapies for endometritis. Accordingly, we tested the immunomodulatory effect of curcumin in the bubaline endometrial stromal cells after treatment with the lipoteichoic acid (LTA) of Gram-positive Staphylococcus aureus and lipopolysaccharide (LPS) of Gram-negative E. coli that activate toll-like receptors (TLR-2 and TLR-4, respectively). Confluent primary culture of endometrial stromal cells was treated with LTA (1 µg/mL) and/or LPS (0.1 µg/mL), in the presence or absence of curcumin (30 µM for 24 h). PGE₂ was assayed in the supernatant and the relative expression of proinflammatory cytokines (PICs) (IL1B, IL6, IL8 and TNFA) transcripts were quantified using real-time PCR. LTA was not effective in stimulating PGE₂ production or upregulating the PIC expression except IL8. LTA+LPS increased PGE₂ production and upregulated IL6 and IL8 genes. Curcumin inhibited the basal and LTA+LPS induced production of PGE₂ and upregulation of PIC production. It was apparent that LPS, but not LTA, is a potent stimulator of PGE₂ from the bubaline endometrial stromal cells. Curcumin downregulated the expression of LPS and/or LTA induced PICs and PGE₂ and may be an alternate to antimicrobial drugs for the therapeutic management of endometritis.

Association of VEGFA, TIMP-3, and IL-6 gene polymorphisms with predisposition to optic neuritis and optic neuritis with multiple sclerosis

BACKGROUND

The etiology of the inflammatory ON is multifactorial. Much attention is paid to the inflammatory and immune processes that are likely to contribute to the demyelination and MS development. IL-6, VEGFA, and TIMP-3 genes are thought to be involved in the inflammatory processes and manifestation of CNS demyelination, so we aimed to determine the relationship between VEGFA rs1413711, TIMP-3 rs9621532, IL-6 rs1800796 gene polymorphisms and ON, and ON with MS.

MATERIALS AND METHODS

Patients with ON, ON with MS, and a random sample of healthy population were enrolled. The genotyping of VEGFA rs1413711, TIMP-3 rs9621532, and IL-6 rs1800796 polymorphisms was carried out using the real-time polymerase chain reaction method.

RESULTS

T/C and C/C genotypes of VEGFA rs1413711 were associated with about threefold increased odds of developing ON in the dominant and codominant models. Each allele C at VEGFA rs1413711 was associated with 1.7-fold increased odds of ON development. IL-6 rs1800796 allele C was more frequent in the ON with MS group compared to the control: 17.6% vs. 7.5%, respectively (p = .040). No statistically significant associations were found between TIMP-3 rs9621532 and the ON development.

CONCLUSION: VEGFA

rs1413711 is associated with the ON development.

The Acute Phase Reaction and Its Prognostic Impact in Patients with Head and Neck Squamous Cell Carcinoma: Single Biomarkers Including C-Reactive Protein Versus Biomarker Profiles

C-reactive protein (CRP) has a prognostic impact in head and neck squamous cell carcinoma (HNSCC). However, the acute phase reaction involves many other proteins depending on its inducing events, including various cytokines that can function as reaction inducers. In the present study, we compared the pretreatment acute phase cytokine profile for 144 patients with potentially curative HNSCC. We investigated the systemic levels of interleukin (IL)6 family mediators (glycoprotein (gp130), IL6 receptor (R)α, IL6, IL27, IL31, oncostatin M (OSM), ciliary neurotrophic factor (CNTF)), IL1 subfamily members (IL1R antagonist (A), IL33Rα), and tumor necrosis factor (TNF)α. Patient subsets identified from this 10-mediator profile did not differ with regard to disease stage, human papilloma virus (HPV) status, CRP levels, or death cause. Increased CRP, IL6, and IL1RA levels were independent markers for HNSCC-related death in the whole patient population. Furthermore, gp130, IL6Rα, and IL31 were suggested to predict prognosis among tumor HPV-negative patients. Only IL6 predicted survival in HPV-positive patients. Finally, we did a clustering analysis of HPV-negative patients based on six acute phase mediators that showed significant or borderline association with prognosis in Kaplan–Meier analyses; three subsets could then be identified, and they differed in survival (p < 0.001). To conclude, (i) HPV-negative and HPV-positive HNSCC patients show similar variations of their systemic acute phase profiles; (ii) the prognostic impact of single mediators differs between these two patient subsets; and (iii) for HPV-negative patients, acute phase profiling identifies three patient subsets that differ significantly in survival.

Review article: experimental therapies in autoimmune hepatitis

BACKGROUND

Current therapeutic options for autoimmune hepatitis (AIH) are limited by adverse events associated with corticosteroids and thiopurines and the limited evidence base for second- and third-line treatment options. Furthermore, current treatment approaches require long-term exposure of patients to pharmacological agents. There have been significant advances in the understanding of the mechanisms underpinning autoimmunity and an expansion in the available therapeutic agents for suppressing autoimmune responses or potentially restoring self-tolerance.

AIM

To review the mechanisms and evidence for experimental therapies that are being actively explored in the management of AIH.

METHODS

We have reviewed the literature relating to a range of novel therapeutic immunomodulatory treatment strategies and drugs.

RESULTS

Drugs which block B cell-activating factor of the tumour necrosis factor family (BAFF) and tumour necrosis factor α are currently in clinical trials for the treatment of AIH. Experimental therapies and technologies to increase immune tolerance, such as pre-implantation factor and regulatory T cell therapies, are undergoing development for application in autoimmune disorders. There is also evidence for targeting inflammatory pathways to control other autoimmune conditions, such as blockade of IL1 and IL6 and Janus-associated kinase (JAK) inhibitors.

CONCLUSIONS

With the range of tools available to clinicians and patients increasing, it is likely that the therapeutic landscape of AIH will change over the coming years and treatment approaches offering lower corticosteroid use and aiming to restore immune self-tolerance should be sought.

CagA orchestrates eEF1A1 and PKCδ to induce interleukin-6 expression in Helicobacter pylori-infected gastric epithelial cells

Background

Helicobacter pylori colonises the stomach of approximately 50% of the global population. Cytotoxin-associated gene A protein (CagA) is one of the important virulent factors responsible for the increased inflammation and increases the risk of developing peptic ulcers and gastric carcinoma. The cytokine interleukin-6 (IL-6) has particularly important roles in the malignant transformation of gastric and intestinal epithelial cells as it is upregulated in H. pylori-infected gastric mucosa. In this study, we investigated the underlying mechanisms of CagA-induced IL-6 up-regulation during H. pylori infection. AGS cells, a human gastric adenocarcinoma cell line, lacking eEF1A1 were infected with CagA⁺ H. pylori (NCTC11637), CagA^- H. pylori (NCTC11637ΔcagA), or transduced by Ad-cagA/Ad-GFP. The expression and production of IL-6 were measured by quantitative real-time reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. The interactions among CagA, eukaryotic translation elongation factor 1-alpha 1 (eEF1A1), protein kinase Cδ (PKCδ), and signal transducer and activator of transcription 3 (STAT3) were determined by western blot or co-immunoprecipitation.

Results

During H. pylori infection, CagA-M (residues 256‒871aa) was found to interact with eEF1A1-I (residues 1‒240aa). NCTC11637 increased the expression of IL-6 in AGS cells compared with NCTC11637ΔcagA whereas knockdown of eEF1A1 in AGS cells completely abrogated these effects. Moreover, the CagA-eEF1A1 complex promoted the expression of IL-6 in AGS cells. CagA and eEF1A1 cooperated to mediate the expression of IL-6 by affecting the activity of p-STAT^S727 in the nucleus. Further, CagA-eEF1A1 affected the activity of STAT3 by recruiting PKCδ. However, blocking PKCδ inhibited the phosphorylation of STAT3^S727 and induction of IL-6 by CagA.

Conclusions

CagA promotes the expression of IL-6 in AGS cells by recruiting PKCδ through eEF1A1 in the cytoplasm to increase the phosphorylation of STAT3^S727 in the nucleus. These findings provide new insights into the function of CagA-eEF1A1 interaction in gastric adenocarcinoma.

Interleukin-6 in Siberian sturgeon (Acipenser baeri): Molecular characterization and immune functional activity

Interleukin-6 (IL-6) is a pleiotropic cytokine with crucial immunoregulatory functions in both innate and adaptive immune responses. However, the IL-6 sequence and function remain unknown in sturgeon, one chondrostean fish. In the present study, we identified an interleukin-6 homolog from Siberian sturgeon (Acipenser baeri), named AbIL-6. Its open reading frame (ORF) was 657 nucleotides in length, encoding a polypeptide of 218 amino acids, which contains a signal peptide and the IL-6 family domain. Phylogenetic analysis showed that sturgeon IL-6 had close relationship with both teleost and chondrichthyes IL-6s. Abil-6 mRNA was highly expressed in spleen, brain and liver tissues of healthy sturgeon, and significantly up-regulated in the spleen, head kidney and liver by A.hydrophila (A.h) challenge. Heat-killed A.h and LPS effectively stimulated Abil-6 transcripts in primary spleen cells in vitro. In order to understand the bioactivity and influence of AbIL-6 on immune responses, recombinant AbIL-6 (rAbIL-6) was synthesized by prokaryotes and demonstrated to promote the proliferation of spleen cells and head kidney cells in vitro. Additionally, intraperitoneal injection of rAbIL-6 induced significantly higher expression of four immuno-related genes including il-1β, cxcl10, mhcIIβ and igm. rAbIL-6 improved the survival rate and reduced the tissue bacterial load after A.h infection. Taken together, these results suggest that AbIL-6 plays an important role in inflammatory responses and immune defense against bacterial infection of sturgeon.

Molecular and functional characterization of IL-6 receptor (IL-6R) and glycoprotein 130 (gp130) in Nile tilapia (Oreochromis niloticus)

Interleukin 6 (IL-6) is a pleiotropic cytokine that exerts its biological functions through interaction with its receptor system consisting of a ligand-specific IL-6 receptor (IL-6R) and a common signal-transducing receptor (gp130). In this study, OnIL-6R and Ongp130 genes from Nile tilapia (Oreochromis niloticus) were identified, and their roles in bacterial or viral infection and in regulation of inflammatory response involved in IL-6 were investigated. The open reading frames (ORFs) of OnIL-6R and Ongp130 are 2019 bp and 2679 bp, encoding 672 and 892 amino acids, respectively. Domain analysis of the deduced amino acid sequences of OnIL-6R and Ongp130 showed that both of them contained a conserved Ig-like domain, FNIII domains, and a WSXWS motif. The transcripts of OnIL-6R and Ongp130 were widely expressed in all examined tissues. Following in vivo challenges with Streptococcus agalactia, Poly I: C and lipopolysaccharide (LPS), the mRNAs of OnIL-6R and Ongp130 were notably induced in liver, head kidney and spleen. The transcriptional up-regulations of OnIL-6R and Ongp130 were also detected in Nile tilapia monocytes/macrophages and lymphocytes after in vitro stimulations with S. agalactiae, Poly I: C and LPS. Besides, increasing mRNA levels of the inflammation-related cytokines (IL-1β, TNF-α, IL-6, IL-10, and MIF) induced by recombinant OnIL-6 could be further enhanced by co-treatment with recombinant soluble OnIL-6R in lymphocytes. Furthermore, recombinant soluble Ongp130 suppressed the induction of expression of these cytokines in lymphocytes when co-stimulated with (r)OnIL-6 and (r)sOnIL-6R. Taken together, these results indicated that OnIL-6R and Ongp130 were likely involved in the resistance to bacterial or viral infection in Nile tilapia. Moreover, soluble OnIL-6R and soluble Ongp130 have an agonistic effect or antagonistic effect in the inflammation response involved in OnIL-6.

Global Transcriptional Profiling Reveals Novel Autocrine Functions of Interleukin 6 in Human Vascular Endothelial Cells

Background

Interleukin 6 (IL6) is a multifunctional cytokine produced by various cells, including vascular endothelial cells. IL6 has both pro- and non-/anti-inflammatory functions, and the response to IL6 is dependent on whether it acts via the membrane-bound IL6 receptor α (IL6Rα) (classic signaling) or the soluble form of the receptor (transsignaling). As human endothelial cells produce IL6 and at the same time express IL6Rα, we hypothesized that IL6 may have autocrine functions.

Methods

Knockdown of IL6 in cultured human endothelial cells was performed using siRNA. Knockdown efficiency was evaluated using ELISA. RNA sequencing was employed to characterize the transcriptional consequence of IL6 knockdown, and Ingenuity Pathway Analysis was used to further explore the functional roles of IL6.

Results

Knockdown of IL6 in cultured endothelial cells resulted in a 84-92% reduction in the release of IL6. Knockdown of IL6 resulted in dramatic changes in transcriptional pattern; knockdown of IL6 in the absence of soluble IL6Rα (sIL6Rα) led to differential regulation of 1915 genes, and knockdown of IL6 in the presence of sIL6Rα led to differential regulation of 1967 genes (fold change 1.5, false discovery rate < 0.05). Pathway analysis revealed that the autocrine functions of IL6 in human endothelial cells are mainly related to basal cellular functions such as regulation of cell cycle, signaling, and cellular movement. Furthermore, we found that knockdown of IL6 activates functions related to adhesion, binding, and interaction of endothelial cells, which seem to be mediated mainly via STAT3.

Conclusion

In this study, a large number of novel genes that are under autocrine regulation by IL6 in human endothelial cells were identified. Overall, our data indicate that IL6 acts in an autocrine manner to regulate basal cellular functions, such as cell cycle regulation, signaling, and cellular movement, and suggests that the autocrine functions of IL6 in human endothelial cells are mediated via IL6 classic signaling.

Exendin-4 exhibits a tumour suppressor effect in SKOVR-3 and OVACR-3 ovarian cancer cells lines by the activation of SIRT1 and inhibition of NF-κB

This study investigated if EX-527 has an anti-tumour effect in SKOV-3 and OVCAR-3 ovarian cancer (OC) cell lines and if this effect involves the SIRT1/NF-κB axis. Cells were cultured in the presence or absence of EX-527, a selective SIRT-1 inhibitor. Exendin-4 significantly induced cell death in both cell lines and inhibited cell migration and invasion. Also, it decreased protein levels of Bcl-2, MMP-9, and ICAM-1 and increased those of Bax, cyclin D1 and cleaved caspase-3. Mechanistically, Exendin-4 increased the activity and nuclear accumulation of SIRT1 and decreased nuclear levels of NF-κB p65; acetylated levels of NF-κB p65, and cytoplasmic levels of p-IKKα and p-IκBα. EX-527 partially ameliorated the effect of Exendin-4 on cell death, migration, and invasion, as well as on the expression of Bcl-2, MMP-9, Bax, cleaved caspase-3 and ICAM-1. In addition, EX-527 did not affect the levels of nuclear p65 and p-p65 (Ser536); p-IκBα (Ser32) and p-IKKαβ. In conclusion, Exendin-4 can suppress OC by inhibiting NF-kB through SIRT1 dependent and independent mechanisms.

Silencing CDC25A inhibits the proliferation of liver cancer cells by downregulating IL‑6 in vitro and in vivo

Cell division cycle 25A (CDC25A) is a core regulator of the cell cycle that has a dual‑specific phosphatase activity, which is closely associated with the occurrence and development of a tumor, and is overexpressed in liver cancer. However, the molecular mechanism of CDC25A in the development of liver cancer remains unclear. The purpose of the present study was to further investigate the effect of CDC25A on cell proliferation in vitro and in vivo and to investigate whether an interaction exists between CDC25A and interleukin (IL)‑6 in liver cancer. An Affymetrix human gene expression profiling chip screened differentially expressed genes in HepG2 cells with silenced CDC25A and the IL‑6 signaling pathway was revealed to be significantly inhibited (P<0.05). In the present study, the effects of CDC25A on cell proliferation and migration were analyzed using cell cycle, MTT and Transwell assays. Reverse transcription‑quantitative PCR, western blot and immunohistochemistry analyses confirmed that silencing the CDC25A gene downregulated the expression of IL‑6 in HepG2 cells and the mRNA and protein expression of IL‑1β, mitogen‑activated protein kinase kinase kinase 14 (NIK) and nuclear factor‑κB (NF‑κB), which are regulatory molecules upstream of IL‑6. In addition, silencing CDC25A by short hairpin RNA inhibited the development of liver cancer xenograft tumor types in nude mice, and decreased the expression of IL‑1β, NIK, NF‑κB and IL‑6 in xenograft tumor types. In conclusion, silencing CDC25A significantly inhibited the proliferation of liver cancer cells in vitro and in vivo, potentially via an interaction with IL‑6 through the downregulation of the IL‑1β/NIK/NF‑κB signaling axis.

MicroRNA‑let‑7a inhibition inhibits LPS‑induced inflammatory injury of chondrocytes by targeting IL6R

Osteoarthritis (OA) is a type of degenerative joint disease that affects the health of the elderly. OA is characterized by articular cartilage degradation and joint inflammation. The present study aimed to investigate the role and mechanism of microRNA-let-7a (Let-7a) in OA by examining its role in lipopolysaccharide (LPS)-induced cartilage inflammatory injury in ATDC5 cells. ATDC5 cells were treated with various concentrations of LPS. The present results suggested that 5 and 10 µg/ml LPS significantly inhibited ATDC5 cell viability, and 5 µg/ml LPS was selected for further experiments. Reverse transcription-quantitative PCR (RT-qPCR) results suggested that treatment with LPS significantly induced the expression levels of multiple inflammatory factors, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6 and IL-8, and increased the expression level of Let-7a in ATDC5 cells. IL-6 receptor (IL-6R) was identified to be a direct target of Let-7a using TargetScan and a dual-luciferase reporter assay. Subsequently, Cell Counting Kit-8 and flow cytometry analyses identified that Let-7a inhibitor could significantly promote cell viability and reduce cell apoptosis in ATDC5 cells treated with LPS, and these effects could be reversed by transfection with small interfering (si)RNA-IL-6R. ELISA was used to examine the expression of inflammatory factors in ATDC5 cells following treatment with LPS. Additionally, RT-qPCR and western blotting were performed to detect the mRNA and protein expression level of IL-6R and STAT3. The present results suggested that Let-7a inhibitor significantly reduced the expression level of TNF-α, IL-1β, IL-6 and IL-8 in ATDC5 cells, and this effect was reversed by transfecting siRNA-IL-6R. Moreover, RT-qPCR and western blot assay results suggested that Let-7a inhibitor significantly increased the expression level of IL-6R and phosphorylated STAT3, and these effects could be reversed by siRNA-IL-6R. Collectively, Let-7a inhibitor increased cell proliferation, reduced apoptosis and inhibited inflammatory response in ATDC5 cells treated with LPS. The present study provided a new potential therapeutic target for OA treatment.

Molecular characterization and biological functioning of interleukin-8 in Siberian sturgeon (Acipenser baeri)

Interleukin-8, otherwise known as CXCL8, is a CXC chemokine that plays a pivotal regulatory role in immune and inflammation responses of animals. Here, we identified an interleukin-8 homologue from Siberian sturgeon (Acipenser baeri), named AbIL-8, which belongs to the lineage 1 group of teleost fish IL-8s. The cDNA of Abil-8 is 1130 bp in length, containing a 5'- untranslated region (UTR) of 50 bp, a 3'- UTR of 783 bp, and an open reading frame (ORF) of 297 bp that encodes a protein consisting of 98 amino acids. The deduced AbIL-8 contained five cysteines, four of which are highly conserved, and an ELR motif typical of known mammalian CXC chemokines was also found preceding the CXC motif. Our phylogenetic analysis showed that AbIL-8 clustered with the CXCL8_L1 sequences from other teleosts, being clearly distinct from those of either birds or mammals. Abil-8 mRNA was constitutively expressed in all tested tissues and significantly up-regulated in the liver and spleen tissues by the bacteria Aernomas hydrophila. The in vitro experiment using primary spleen cells stimulated with heat-killed Aernomas hydrophila or lipopolysaccharide (LPS) revealed a similar expression pattern to that found in vivo, whereas stimulation on spleen cells with β-glucan or polyI:C elicited negligible changes in levels of Abil-8 mRNA. Purified recombinant AbIL-8 not only exhibited chemotactic activity for lymphocytes and monocytes in peripheral blood leukocytes (PBLs) and, to a lesser extent, spleen cells, but also stimulated the proliferation of spleen cells at 10 ng/mLor above. Furthermore, intraperitoneal injection of rAbIL-8 also up-regulated the expression of immuno-related genes (IL-6, IgM and MHCIIβ) at 24 h. Collectively, these results enhance our understanding of how IL-8 functions in the regulation of the immune responses in sturgeon.

Effects of blood sample handling procedures on measurable interleukin 6 in plasma and serum

Introduction

Interleukin‐6(IL‐6) measurement is used as a biomarker in medical diagnosis, therapy, and prognosis in various diseases. However, several pre‐analytical factors may yield a false IL‐6 result. In this study, we set out to investigate the effects of corrected blood sample handling procedures on measurable IL‐6.

Method

EDTA plasma and serum samples were collected from 45 healthy individuals. The participants were divided into three groups to perform different handling procedures. Different centrifugal timing, storage temperature, and time were executed on the samples. The changed trends of IL‐6 levels were analyzed.

Results

At baseline, while the paired plasma and serum IL‐6 values had a good correlation, the plasma levels were higher than serum. In general, the unseparated EDTA plasma kept steady with time. With the increase in storage temperature and time, a more pronounced rise in unseparated serum IL‐6 was observed. Nevertheless, the samples in Group 3 which centrifuged and separated immediately kept stable after a different temperature and longtime storage.

Conclusion

Sample types, centrifugal timing, storage temperature, and time may affect the IL‐6 levels. A standard blood sample handling procedure should be performed to ensure the accuracy and stability of IL‐6 values.

Immunomodulatory effect of curcumin on lipopolysaccharide- and/or flagellin-induced production of prostaglandin E2 and relative expression of proinflammatory cytokines in the primary bubaline endometrial stromal cells

Developing alternate therapies for bovine endometritis is important in the context of drug residues in the milk and emergence of antimicrobial resistant bacteria. In this regard, we studied the immunomodulatory effect of curcumin 30 µM, on lipopolysaccharide- (LPS) and/or flagellin (100 ng/ml each)-induced prostaglandin E₂ (PGE₂ ) and proinflammatory cytokines (PIC) using primary bubaline endometrial stromal cells. After 24 hr treatment, the supernatant was assayed for PGE₂ while cells were used for relative quantification of cytokines like IL-1β, IL-6, IL-8 and TNF α transcripts using a control group as calibrator. LPS was found to possess potent stimulatory effect on PGE₂ production, whereas the flagellin was not as potent as LPS in stimulating the PGE₂ production either per se or in combination with LPS. LPS markedly up-regulated the transcripts of IL-8 and IL-6 as compared to IL-1β and TNF α in the bubaline endometrial stromal cells. Except for IL-8, flagellin did not up-regulate other PICs. There was no additive effect between LPS and flagellin on the up-regulation of inflammatory cytokines. Curcumin inhibited the LPS-induced up-regulation of PIC with strong down-regulation of IL-8. The inhibitory effects of curcumin on the inflammatory mediators suggest a potential in the treatment of bovine endometritis.

Preliminary Study on the Relationship Between Inflammation and Hemifacial Spasm

BACKGROUND

Complete pathogenesis of hemifacial spasm (HFS) is unknown. In some patients with HFS, thickened, opaque, and sticky arachnoid membranes have been found during microvascular decompression procedures. This phenomenon indicates a possible relationship between inflammation and HFS. The aim of this study was to explore the role of inflammation in pathogenesis of HFS.

METHODS

Levels of interferon-γ, interleukin-2 receptor, interleukin-6 (IL-6), interleukin-8, interleukin-10, and tumor necrosis factor α and white blood cell (WBC), neutrophil, and lymphocyte counts were compared between patients with HFS, patients with lumbar disc herniation, and healthy control subjects. A receiver operating characteristic curve analysis was performed to evaluate the diagnostic significance of peripheral blood inflammatory markers for HFS. All the inflammatory markers were further analyzed by single and multiple logistic regression analysis.

RESULTS

Patients with HFS had greater IL-6, interleukin-8, white blood cell count, and neutrophil count than patients with lumbar disc herniation and healthy control subjects. Area under curve values of IL-6, white blood cell count, and neutrophil count were >0.8. Multiple logistic regression analysis indicated that only interleukin-2 receptor and IL-6 were relevant to HFS.

CONCLUSIONS

Inflammation is relative to HFS. IL-6 may be 1 of many factors involved in pathogenesis of HFS.

Association of interleukin-6 gene promoter polymorphism with acne vulgaris and its severity

BACKGROUND

Acne vulgaris (AV) is an inflammatory disorder with a possible genetic background. Different cytokines and mediators are involved in its pathogenesis.

AIM

Our aim was to investigate the interleukin (IL)-6 572 polymorphism in patients with AV and its relation to patient sex and acne severity.

METHODS

In total, 30 patients with acne and 20 healthy controls (HCs) were enrolled. The Global Acne Grading System was used to assess acne severity. The IL-6 572 gene promoter polymorphism was assessed using the PCR-restriction fragment length polymorphism method.

RESULTS

There was a significantly higher association of IL-6 572 variants genotypes in patients with acne (93%) compared with the HC group (45%) (P < 0.001), with a higher incidence of the IL-6 572 CC polymorphism in patients with acne. A significant difference (P < 0.001) between C and G alleles in patients vs. HCs was detected. There were no significant associations between the IL-6 572 variant genotypes and either patient sex or AV severity.

CONCLUSION

IL-6 gene promoter polymorphism might have a role in AV susceptibility but it is not related to AV severity.

Interleukin-6 gets involved in response to bacterial infection and promotes antibody production in Nile tilapia (Oreochromis niloticus)

Interleukin 6 (IL-6), a pleiotropic cytokine, plays an important role in humoral immune response, not only inducing the differentiation of B cells into plasma cells, but also promoting antibody-secreting cells (ASCs) to produce antibodies. In this study, Nile tilapia (Oreochromis niloticus) IL-6 (OnIL-6) was identified and characterized at expression level in response to bacterial infection and promotion of antibody production. The open reading frame of OnIL-6 ORF is consisted of 663 bp encoding a polypeptide of 220 amino acids. The deduced OnIL-6 protein contained an IL-6/G-CSF family signature, two conserved cysteine, and four α-helix bundles, which was highly homologous to other species. Spatial mRNA expression analysis revealed that the highest expression of OnIL-6 was observed in the thymus. After in vivo challenges of lipopolysaccharide (LPS) and Streptococcus agalactia (S. agalactiae), OnIL-6 expressions were significantly up-regulated in head kidney and spleen. The similar up-regulation of OnIL-6 was observed in the head kidney and spleen leukocytes in vitro stimulation with LPS and S. agalactiae. In addition, inducement with the recombinant OnIL-6 ((r)OnIL-6) in vitro caused significant increases in expressions of both sIgM and mIgM. Moreover, the (r)OnIL-6 stimulation enhanced the secretion of sIgM (more especially in P50 plasma-like B cells) and the production of mIgM in P60 and P70 B cell subsets (resting B cells, activated B cells and plasmablast-like B cells) in vitro. Taken together, this study indicated that OnIL-6 might be involved in host defense against bacterial infection and promote the production of antibody in Nile tilapia.