α1-AR overactivation induces cardiac inflammation through NLRP3 inflammasome activation

Acute sympathetic stress causes excessive secretion of catecholamines and induces cardiac injuries, which are mainly mediated by β-adrenergic receptors (β-ARs). However, α₁-adrenergic receptors (α₁-ARs) are also expressed in the heart and are activated upon acute sympathetic stress. In the present study, we investigated whether α₁-AR activation induced cardiac inflammation and the underlying mechanisms. Male C57BL/6 mice were injected with a single dose of α₁-AR agonist phenylephrine (PE, 5 or 10 mg/kg, s.c.) with or without pretreatment with α-AR antagonist prazosin (5 mg/kg, s.c.). PE injection caused cardiac dysfunction and cardiac inflammation, evidenced by the increased expression of inflammatory cytokine IL-6 and chemokines MCP-1 and MCP-5, as well as macrophage infiltration in myocardium. These effects were blocked by prazosin pretreatment. Furthermore, PE injection significantly increased the expression of NOD-like receptor protein 3 (NLRP3) and the cleavage of caspase-1 (p20) and interleukin-18 in the heart; similar results were observed in both Langendorff-perfused hearts and cultured cardiomyocytes following the treatment with PE (10 μM). Moreover, PE-induced NLRP3 inflammasome activation and cardiac inflammation was blocked in Nlrp3^-/- mice compared with wild-type mice. In conclusion, α₁-AR overactivation induces cardiac inflammation by activating NLRP3 inflammasomes.

Urine Markers of Kidney Tubule Cell Injury and Kidney Function Decline in SPRINT Trial Participants with CKD

BACKGROUND AND OBJECTIVES

eGFR and albuminuria primarily reflect glomerular function and injury, whereas tubule cell atrophy and interstitial fibrosis on kidney biopsy are important risk markers for CKD progression. Kidney tubule injury markers have primarily been studied in hospitalized AKI. Here, we examined the association between urinary kidney tubule injury markers at baseline with subsequent loss of kidney function in persons with nondiabetic CKD who participated in the Systolic Blood Pressure Intervention Trial (SPRINT).

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Among 2428 SPRINT participants with CKD (eGFR<60 ml/min per 1.73 m²) at baseline, we measured urine markers of tubule injury (IL-18, kidney injury molecule-1 [KIM-1], neutrophil gelatinase-associated lipocalin [NGAL]), inflammation (monocyte chemoattractant protein-1 [MCP-1]), and repair (human cartilage glycoprotein-40 [YKL-40]). Cox proportional hazards models evaluated associations of these markers with the kidney composite outcome of 50% eGFR decline or ESKD requiring dialysis or kidney transplantation, and linear mixed models evaluated annualized change in eGFR.

RESULTS

Mean participant age was 73±9 (SD) years, 60% were men, 66% were white, and mean baseline eGFR was 46±11 ml/min per 1.73 m². There were 87 kidney composite outcome events during a median follow-up of 3.8 years. Relative to the respective lowest quartiles, the highest quartiles of urinary KIM-1 (hazard ratio, 2.84; 95% confidence interval [95% CI], 1.31 to 6.17), MCP-1 (hazard ratio, 2.43; 95% CI, 1.13 to 5.23), and YKL-40 (hazard ratio, 1.95; 95% CI, 1.08 to 3.51) were associated with higher risk of the kidney composite outcome in fully adjusted models including baseline eGFR and urine albumin. In linear analysis, urinary IL-18 was the only marker associated with eGFR decline (-0.91 ml/min per 1.73 m² per year for highest versus lowest quartile; 95% CI, -1.44 to -0.38), a finding that was stronger in the standard arm of SPRINT.

CONCLUSIONS

Urine markers of tubule cell injury provide information about risk of subsequent loss of kidney function, beyond the eGFR and urine albumin.

Interleukin-18 levels in the hippocampus and behavior of adult rat offspring exposed to prenatal restraint stress during early and late pregnancy

Exposure to maternal stress during prenatal life is associated with an increased risk of neuropsychiatric disorders, such as depression and anxiety, in offspring. It has also been increasingly observed that prenatal stress alters the phenotype of offspring via immunological mechanisms and that immunological dysfunction, such as elevated interleukin-18 levels, has been reported in cultures of microglia. Prenatal restraint stress (PRS) in rats permits direct experimental investigation of the link between prenatal stress and adverse outcomes. However, the majority of studies have focused on the consequences of PRS delivered in the second half of pregnancy, while the effects of early prenatal stress have rarely been examined. Therefore, pregnant rats were subjected to PRS during early/middle and late gestation (days 8-14 and 15-21, respectively). PRS comprised restraint in a round plastic transparent cylinder under bright light (6500 lx) three times per day for 45 minutes. Differences in interleukin-18 expression in the hippocampus and in behavior were compared between offspring rats and control rats on postnatal day 75. We found that adult male offspring exposed to PRS during their late prenatal periods had higher levels of anxiety-related behavior and depression than control rats, and both male and female offspring exhibited higher levels of depression-related behavior, impaired recognition memory and diminished exploration of novel objects. Moreover, an elevated level of interleukin-18 was observed in the dorsal and ventral hippocampus of male and female early- and late-PRS offspring rats. The results indicate that PRS can cause anxiety and depression-related behaviors in adult offspring and affect the expression of interleukin-18 in the hippocampus. Thus, behavior and the molecular biology of the brain are affected by the timing of PRS exposure and the sex of the offspring. All experiments were approved by the Animal Experimentation Ethics Committee at Kunming Medical University, China (approval No. KMMU2019074) in January 2019.

Evaluation of the mechanism of cordyceps polysaccharide action on rat acute liver failure

INTRODUCTION

This study aimed to investigate the mechanism of action of cordyceps polysaccharide on rat acute liver failure (ALF).

MATERIAL AND METHODS

Sixty rats were randomly divided into five groups: a normal group, a model group without cordyceps polysaccharide and groups with cordyceps polysaccharide in three different doses (5, 10 and 20 mg/ml). Serum alanine aminotransferase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), and total bilirubin (TBIL) contents were measured for assessing liver function. Hematoxylin and eosin (HE) staining was used for observing liver pathology. Apoptosis was detected through the method of terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL) staining. Protein expression levels of caspase-1, interleukin-18 (IL-18), IL-10, vascular endothelial growth factor (VEGF), and stromal cell-derived factor-1α (SDF-1α) in liver tissue were detected by Western blot. Proliferating cell nuclear antigen (PCNA) and signal regulatory protein-α1 (SIRPα1) contents were measured by PCR.

RESULTS

The rat ALF model was established with D-galactosamine induced by lipopolysaccharide (LPS). After modelling, tissue HE staining showed typical manifestation of acute liver injury that emerged in the rat ALF model. The liver failure group showed higher levels of serum ALT and AST, as well as hepatocyte apoptosis, than the groups treated with cordyceps polysaccharide. Cordyceps polysaccharide can effectively suppress the protein expression of caspase-1, IL-18, and IL-10, while simultaneously increasing the protein expression of VEGF and SDF-1α, as well as the mRNA expression of PCNA and SIRPα1.

CONCLUSIONS

Cordyceps polysaccharide can alleviate the immune response and inflammatory injury in ALF by regulating the balance of pro-inflammatory and anti-inflammatory factors and reducing the apoptosis.

Analysis of genes linked to depressive-like behaviors in interleukin-18-deficient mice: Gene expression profiles in the brain

Interleukin (IL)-18 is an interferon γ-inducing inflammatory cytokine associated with function of the immune system and other physiological functions. IL-18-deficient (Il18 ^-/-) mice exhibit obesity, dyslipidemia, non-alcoholic steatohepatitis and depressive-like behavioral changes. Therefore, IL-18 has a number of important roles associated with immunity, energy homeostasis and psychiatric conditions. In the present study, gene expression in the brains of Il18 ^-/- mice was analyzed to identify genes associated with the depressive-like behaviors and other impairments displayed by Il18 ^-/- mice. Using whole genome microarray analysis, gene expression patterns in the brains of Il18 ^+/+ and Il18 ^-/- mice at 6 and 12 weeks of age were examined and compared. Subsequently, genes were categorized using Ingenuity^® Pathway Analysis (IPA). At 12 weeks of age, 2,805 genes were identified using microarray analysis. Genes related to 'Major depression' and 'Depressive disorders' were identified by IPA core analysis, and 13 genes associated with depression were isolated. Among these genes, fibroblast growth factor receptor 1 (Fgfr1); protein tyrosine phosphatase, non-receptor type 1 (Ptpn1); and urocortin 3 (Ucn3) were classed as depression-inducing and the other genes were considered depression-suppressing genes. Subsequently, the interactions between the microarray results at 6 weeks of age and the above three depression-inducing genes were analyzed to search for effector genes of depression at 12 weeks of age. This analysis identified cyclin D1 (Ccnd1) and NADPH oxidase 4 (Nox4). The microarray analysis results were correlated with the results of reverse transcription-quantitative PCR (RT-qPCR). Overall, the results suggest that Fgfr1, Ptpn1 and Ucn3 may be involved in depression-like changes and Ccnd1 and Nox4 regulate these three genes in IL-18-deficient mice.

Engineered Tumor-Targeted T Cells Mediate Enhanced Anti-Tumor Efficacy Both Directly and through Activation of the Endogenous Immune System

Chimeric antigen receptor (CAR) T cell therapy has proven clinically beneficial against B cell acute lymphoblastic leukemia and non-Hodgkin’s lymphoma. However, suboptimal clinical outcomes have been associated with decreased expansion and persistence of adoptively transferred CAR T cells, antigen-negative relapses, and impairment by an immunosuppressive tumor microenvironment. Improvements in CAR T cell design are required to enhance clinical efficacy, as well as broaden the applicability of this technology. Here, we demonstrate that interleukin-18 (IL-18)-secreting CAR T cells exhibit enhanced in vivo expansion and persistence and significantly increase long-term survival in syngeneic mouse models of both hematological and solid malignancies. In addition, we demonstrate that IL-18-secreting CAR T cells are capable of modulating the tumor microenvironment, as well as enhancing an effective endogenous anti-tumor immune response. IL-18-secreting CART cells represent a promising strategy to enhance the clinical outcomes of adoptive T cell therapy.

Endothelial Cell-Derived Interleukin-18 Released During Ischemia Reperfusion Injury Selectively Expands T Peripheral Helper Cells to Promote Alloantibody Production

BACKGROUND

Ischemia reperfusion injury (IRI) predisposes to the formation of donor-specific antibodies, a factor contributing to chronic rejection and late allograft loss.

METHODS

We describe a mechanism underlying the correlative association between IRI and donor-specific antibodies by using humanized models and patient specimens.

RESULTS

IRI induces immunoglobulin M-dependent complement activation on endothelial cells that assembles an NLRP3 (NOD-like receptor pyrin domain-containing protein 3) inflammasome via a Rab5-ZFYVE21-NIK axis and upregulates ICOS-L (inducible costimulator ligand) and PD-L2 (programmed death ligand 2). Endothelial cell-derived interleukin-18 (IL-18) selectively expands a T-cell population (CD4+CD45RO+PD-1^hiICOS+CCR2+CXCR5-) displaying features of recently described T peripheral helper cells. This population highly expressed IL-18R1 and promoted donor-specific antibodies in response to IL-18 in vivo. In patients with delayed graft function, a clinical manifestation of IRI, these cells were Ki-67+IL-18R1+ and could be expanded ex vivo in response to IL-18.

CONCLUSIONS

IRI promotes elaboration of IL-18 from endothelial cells to selectively expand alloreactive IL-18R1+ T peripheral helper cells in allograft tissues to promote donor-specific antibody formation.

A Batf3/Nlrp3/IL-18 Axis Promotes Natural Killer Cell IL-10 Production during Listeria monocytogenes Infection

The bacterial pathogen Listeria monocytogenes (Lm) capitalizes on natural killer (NK) cell production of regulatory interleukin (IL)-10 to establish severe systemic infections. Here, we identify regulators of this IL-10 secretion. We show that IL-18 signals to NK cells license their ability to produce IL-10. IL-18 acts independent of IL-12 and STAT4, which co-stimulate IFNγ secretion. Dendritic cell (DC) expression of Nlrp3 is required for IL-18 release in response to the Lm p60 virulence protein. Therefore, mice lacking Nlrp3, Il18, or Il18R fail to accumulate serum IL-10 and are highly resistant to systemic Lm infection. We further show that cells expressing or dependent on Batf3 are required for IL-18-inducing IL-10 production observed in infected mice. These findings explain how Il18 and Batf3 promote susceptibility to bacterial infection and demonstrate the ability of Lm to exploit NLRP3 for the promotion of regulatory NK cell activity.

Activation of Human NK Cells by Bordetella pertussis Requires Inflammasome Activation in Macrophages

Pertussis is a highly contagious respiratory infection caused by the bacterium Bordetella pertussis. Humans are the only known natural reservoir of B. pertussis. In mice, macrophages and NK cells have a key role in confining B. pertussis to the respiratory tract. However, the mechanisms underlying this process, particularly during human infections, remain unclear. Here we characterized the activation of human macrophages and NK cells in response to B. pertussis and unraveled the role of inflammasomes in this process. NLRP3 inflammasome activation by B. pertussis in human macrophage-like THP-1 cells and primary monocyte-derived macrophages (mo-MΦ) was shown by the visualization of ASC-speck formation, pyroptosis, and the secretion of caspase-mediated IL-1β and IL-18. In contrast to macrophages, stimulation of human CD56⁺CD3⁻ NK cells by B. pertussis alone did not result in activation of these cells. However, co-culture of B. pertussis-stimulated mo-MΦ and autologous NK cells resulted in high amounts of IFNγ secretion and an increased frequency of IL-2Rα⁺ and HLA-DR⁺ NK cells, indicating NK cell activation. This activation was significantly reduced upon inhibition of inflammasome activity or blocking of IL-18 in the mo-MΦ/NK cell co-culture. Furthermore, we observed increased secretion of proinflammatory cytokines in the B. pertussis-stimulated mo-MΦ/NK co-culture compared to the mo-MΦ single culture. Our results demonstrate that B. pertussis induces inflammasome activation in human macrophages and that the IL-18 produced by these cells is required for the activation of human NK cells, which in turn enhances the pro-inflammatory response to this pathogen. Our data provides a better understanding of the underlying mechanisms involved in the induction of innate immune responses against B. pertussis. These findings contribute to the knowledge required for the development of improved intervention strategies to control this highly contagious disease.

Mycophenolic acid enhanced lipopolysaccharide-induced interleukin-18 release in THP-1 cells via activation of the NLRP3 inflammasome

Background: Interleukin (IL)-18 is a pro-inflammatory cytokine that has important functions in host defense. The maturation and secretion of IL-18 has been shown to be regulated by the NOD-like receptor (NLR) family pyrin domain-containing 3 (NLRP3) inflammasome. Mycophenolic acid (MPA), the active metabolite of mycophenolate mofetil (MMF), in association with lipopolysaccharide (LPS), is able to promote the secretion of IL-18, but the mechanism remains unknown. This study aims to explore the mechanism by which MPA synergizes with LPS to induced IL-18 release. Methods: THP-1 cells were stimulated with LPS and MPA and treated with or without the inhibitors of caspase-1, Ac-YVAD-cmk or KCl; IL-18 in the supernatants was measured by ELISA. The intracellular protein levels of NF-κB p-p65, pro-IL-18, NLRP3, and cleaved caspase-1(p20) were measured by Western blot. Results: We found that MPA alone failed to induce IL-18, whereas MPA enhanced LPS-mediated IL-18 release. MPA did not affect the intracellular protein levels of NF-κB p-p65 or pro-IL-18 but activated the NLRP3 inflammasome. Ac-YVAD-cmk or increasing extracellular K⁺ blocked the activation of caspase-1 and attenuated the release of IL-18. Conclusions: Taken together, MPA synergized with LPS to induce the release of IL-18 via activating the NLRP3 inflammasome and increasing the degradation of pro-IL-18, rather than by enhancing the production of pro-IL-18.

The SPRINT trial suggests that markers of tubule cell function in the urine associate with risk of subsequent acute kidney injury while injury markers elevate after the injury

Urine markers can quantify tubular function including reabsorption (α-1 microglobulin [α1m]) and β-2-microglobulin [β2m]) and protein synthesis (uromodulin). Individuals with tubular dysfunction may be less able to compensate to insults than those without, despite similar estimated glomerular filtration rate (eGFR) and albuminuria. Among Systolic Blood Pressure Intervention Trial (SPRINT) participants with an eGFR under 60 ml/min/1.73m2, we measured urine markers of tubular function and injury (neutrophil gelatinase-associated lipocalin [NGAL], kidney injury molecule-1 [KIM-1], interleukin-18 [IL-18], monocyte chemoattractant protein-1, and chitinase-3-like protein [YKL-40]) at baseline. Cox models evaluated associations with subsequent acute kidney injury (AKI) risk, adjusting for clinical risk factors, baseline eGFR and albuminuria, and the tubular function and injury markers. In a random subset, we remeasured biomarkers after four years, and compared changes in biomarkers in those with and without intervening AKI. Among 2351 participants, 184 experienced AKI during 3.8 years mean follow-up. Lower uromodulin (hazard ratio per two-fold higher (0.68, 95% confidence interval [0.56, 0.83]) and higher α1m (1.20; [1.01, 1.44]) were associated with subsequent AKI, independent of eGFR and albuminuria. None of the five injury markers were associated with eventual AKI. In the random subset of 947 patients with repeated measurements, the 59 patients with intervening AKI versus without had longitudinal increases in urine NGAL, IL-19, and YKL-40 and only 1 marker of tubule function (α1m). Thus, joint evaluation of tubule function and injury provided novel insights to factors predisposing to AKI, and responses to kidney injury.

Dual roles of IL-18 in colitis through regulation of the function and quantity of goblet cells

The main aim of the present study was to investigate the dual roles and mechanism of interleukin (IL)‑18 in dextran sulfate sodium (DSS)‑induced colitis. Firstly, meta‑analysis was used to explore whether the levels of IL‑18 were different in patients with colon cancer or inflammatory bowel disease. The results demonstrated that IL‑18 (rs187238, ‑137G/C) increased the incidence rate of colon cancer in patients, while IL‑18 (rs187238, ‑137G/C) decreased the incidence rate of ulcerative colitis or Crohn's disease in patients. Therefore, IL‑18 (rs187238, ‑137G/C) may have a dual function in colitis. Next, the functional role of IL‑18 in colitis was further investigated, by use of a DSS‑induced colitis mouse model. Pre‑treatment of the mice with IL‑18 increased body weight, augmented colon length, reduced inflammatory infiltration, promoted mucin (Muc)‑2 expression, increased the function and quantity of goblet cells and increased the mRNA levels of resistin‑like molecule (RELM) β and trefoil factor family (TFF) 3 in mice with DSS‑induced colitis, through the IL‑22/STAT3 pathway. By contrast, treatment with IL‑18 at later stages of the disease reduced body weight, decreased colon length, enhanced inflammatory infiltration and reduced Muc‑2 expression, decreased the function and quantity of goblet cells and inhibited the mRNA levels of RELMβ and TFF3 in mice with DSS‑induced colitis. In conclusion, IL‑18 served a dual function in colitis by regulating the function of goblet cells. The anti‑inflammatory effects of IL‑18 were observed in the early stage of colitis‑induced inflammation, while the pro‑inflammatory effects were observed in the later stages of the disease.

The cleavage of gasdermin D by caspase-11 promotes tubular epithelial cell pyroptosis and urinary IL-18 excretion in acute kidney injury

Inflammation and tubular cell death are the hallmarks of acute kidney injury. However, the precise mechanism underlying these effects has not been fully elucidated. Here we tested whether caspase-11, an inflammatory member of the caspase family, was increased in cisplatin or ischemia-reperfusion-induced acute kidney injury. Caspase-11 knockout mice after cisplatin treatment exhibited attenuated deterioration of renal functional, reduced tubular damage, reduced macrophage and neutrophil infiltration, and decreased urinary IL-18 excretion. Mechanistically, the upregulation of caspase-11 by either cisplatin or ischemia-reperfusion cleaved gasdermin D (GSDMD) into GSDMD-N, which translocated onto the plasma membrane, thus triggering cell pyroptosis and facilitated IL-18 release in primary cultured renal tubular cells. These results were further confirmed in GSDMD knockout mice that cisplatin-induced renal morphological and functional deterioration as well as urinary IL-18 excretion were alleviated. Furthermore, deficiency of GSDMD significantly suppressed cisplatin-induced IL-18 release but not the transcription and maturation level of IL-18 in tubular cells. Thus, our study indicates that caspase-11/GSDMD dependent tubule cell pyroptosis plays a significant role in initiating tubular cell damage, urinary IL-18 excretion and renal functional deterioration in acute kidney injury.

Hepatitis B core antigen can regulate NLRP3 inflammasome pathway in HepG2 cells

Hepatitis B virus (HBV) has four open reading frames (ORFs) of which ORF C is consists of the pre Core and Core genes encodes the Hepatitis B core antigen (HBcAg) and Hepatitis B e antigen (HBeAg). Studies have shown that HBeAg significantly inhibits the NLRP3 inflammasome activation and interleukin-1β (IL-1β) production. However, the role of HBcAg and ORF C proteins (in this paper, ORF C proteins = HBcAg + HBeAg) were remain unclear. Our study aims to assess whether HBcAg and ORF C proteins can affect the NLRP3 inflammasome pathway. Vectors expressing ORF C proteins and HBcAg were designed and transfected into HepG2 cells. And then, cells were stimulated with lipopolysaccharide (LPS). Activation of the NLRP3 inflammasome and the levels of IL-1β and IL-18 were evaluated by Western blot analysis, quantitative reverse-transcription polymerase chain reaction, enzyme-linked immunosorbent assay, and immunofluorescence. The expression of NLRP3 and IL-1β peaked when HepG2 cells were stimulated with 1000 ng/mL LPS for 18 to 24 hours. HBcAg, but not ORF C proteins, promoted LPS-induced NLRP3 inflammasome activation and IL-1β production. These findings provide a novel mechanism on how the HBV causes liver inflammation and may provide insights into the search for new therapeutic strategies.

Predictive value of IL-18 and IL-10 in the prognosis of patients with colorectal cancer

Predictive value of serum interleukin 10 (IL-10) and interleukin 18 (IL-18) expression in patients with colorectal cancer (CRC) was investigated. This study retrospectively analyzed the medical records of 146 patients with CRC admitted to the Binzhou Medical University Hospital as the study group, and collected the physical examination data of 82 volunteers as the control group. The expression levels of IL-10 and IL-18 in the serum were measured by enzyme-linked immunosorbent assay (ELISA). A 60-month follow-up on patients in the study group was performed to make records of their prognosis. The expressions of IL-10 and IL-18 were statistically different in patients with different Dukes stages, tumor sizes, histological grades, and different situations of distant metastasis of cancer cells (P<0.05); with a gradual downward trend following the operation. The expression levels of serum IL-10 and IL-18 in the study group 7 days after the operation were lower than the levels before the operation (P<0.05), and the expression levels of IL-10 and IL-18 of patients in the study group on the day of discharge were lower than the expression levels 7 days after the operation (P<0.05). The expressions of IL-10 and IL-18 of patients with reoccurred CRC after the operation were significantly higher than that of patients without recurrence of CRC in the study group (P<0.05). Thus, IL-10 and IL-18 are highly expressed in the serum of CRC patients, which makes IL-10 and IL-18 useful to serve as indicators to determine the prognosis of CRC patients. The lower the expression levels of IL-10 and IL-18, the lower the cancer recurrence rate, the better the prognosis and the longer the survival time.

Serum interleukin-18: A novel prognostic indicator for acute respiratory distress syndrome

The aim of this study is to determine the biological function of serum interleukin-18 (IL-18) on prognosis in acute respiratory distress syndrome (ARDS).From October 2016 to September 2017, 150 patients with ARDS in the ICU were enrolled according to the Berlin 2012 definition. The enzyme-linked immunosorbent assay (ELISA) was used to detect the expression level of IL-18 in serum isolated from the patients. Patients were divided into survival group (82 cases) and non-survival group (68 cases) and followed up for at least 2 months. The serum IL-18 expression level on the prognosis was calculated by receiver operating characteristic curve (ROC).The expression level of serum IL-18 was significantly higher in the non-survival group than that in the survival group (P < .05). Based on the ROC curve, the sensitivity and specificity of IL-18 as a predictor of prognosis at a cutoff of 509.5 pg/mL were 88% and 82%, respectively, and the area under the curve (RUC) was 0.84 (P < .05).The expression level of serum IL-18 could be used to evaluate the possible outcomes of patients with ARDS.

Association between interleukin-18 variants and prostate cancer in Slovak population

Interleukin-18 (IL-18), pro-inflammatory cytokine, plays important role in antitumor immunity. Polymorphisms in the IL-18 gene may lead to its altered production/activity and such modulate susceptibility to prostate cancer. The aim of this study was to evaluate the relationship between the -607 and +105 polymorphisms in the IL-18 gene and the risk of prostate cancer development and progression in Slovak population. The study was performed using 425 patients with prostate cancer, 270 patients with benign prostatic hyperplasia (BHP) and 263 healthy male controls. The statistically significant association of the -607 AC genotype (OR = 2.24; p < 0.001), CC genotype (OR = 1.86; p = 0.006), as well as C allele (OR = 1.27; p = 0.033) with the higher risk of prostate cancer development was observed. No association of the IL-18 -607 polymorphism and BHP was detected. The subset analysis revealed the significant association of the -607 AC genotype (OR = 2.01; p = 0.008) with development of higher-grade carcinomas (Gleason score ≥7) and the strong association of the -607 AC genotype (OR = 3.11; p < 0.001), CC genotype (OR = 2.96; p < 0.001) as well as C allele (OR = 1.51; p = 0.003) with the higher risk of prostate cancer development in the group of patients with PSA < 10 ng/ml. The -607 AC genotype was also connected with significantly higher IL-18 plasma concentrations. No association between the IL-18 +105 polymorphism and prostate cancer was observed. The analysis of the distribution of the -607 and +105 haplotypes showed significant association of the - 607 C/ + 105 A and - 607 C/ + 105 C haplotypes with the risk of prostate cancer. This study found that the IL-18 -607 promoter polymorphism could contribute to prostate cancer development in Slovak population. Its presence was also associated with development of higher-grade carcinomas and therefore may influences the prognosis and aggressiveness of the disease.

Interleukin-18-deficient mice develop hippocampal abnormalities related to possible depressive-like behaviors

Interleukin-18 (IL-18) is an inflammatory cytokine linked to major depressive disorder (MDD). MDD is closely related to metabolic disorders, such as diabetes mellitus (DM) and obesity. Moreover, DM is associated with cognitive impairment and promotes apoptosis of hippocampal cells by activating pro-apoptotic and inhibiting anti-apoptotic factors. IL-18-deficient (Il18^-/-) mice are obese and have DM. Therefore, we hypothesized a close relationship between IL-18 and death of hippocampal cells, affecting neurogenesis related to behavioral changes such as MDD. Il18^-/- male mice were generated on the C57Bl/6 background and Il18^+/+ mice were used as controls. Behavioral, histopathological, and molecular responses, as well as responses to intracerebral recombinant IL-18 administration, were examined. Compared with Il18^+/+ mice, Il18^-/- mice had impaired learning and memory and exhibited lower motivation. In the Il18^-/- mice, degenerated mitochondria were detected in synaptic terminals in the molecular layer, the polymorphic layer, and in mossy fibers in the dentate gyrus, suggesting mitochondrial abnormalities. Because of the degeneration of mitochondria in the dentate gyrus, in which pro-apoptotic molecules were upregulated and anti-apoptotic factors were decreased, apoptosis inducers were not cleaved, indicating inhibition of apoptosis. In addition, neurogenesis in the dentate gyrus and the maturity of neuronal cells were decreased in the Il18^-/- mice, while intracerebral administration of recombinant IL-18 promoted significant recovery of neurogenesis. Our findings suggested that IL-18 was indispensable for mitochondrial homeostasis, sustaining clearance of degenerative neural cells, and supporting neurogenesis, normal neuronal maturation and hippocampal function.

Acute rheumatic fever associated with tenosynovitis and a unique cytokine profile

Acute rheumatic fever (ARF), caused by group A β-hemolytic streptococcus infection, is characterized by inflammation affecting several organs. There are few reports on magnetic resonance imaging (MRI) findings in patients with ARF. An 8-year-old Japanese boy presented with a prolonged fever of unknown cause and swelling of his right hand. MRI of his hand revealed tenosynovitis. Migratory arthritis and erythema marginatum appeared following the hand swelling. We diagnosed him as having ARF based on the clinical course and serological testing for group A β-hemolytic streptococcus. His serum interleukin-18 levels were lower than those typically seen in cases of systemic juvenile idiopathic arthritis (sJIA). After treatment with naproxen, his symptoms improved immediately. In conclusion, MRI findings of tenosynovitis may be useful for the diagnosis of not only sJIA but also ARF in patients presenting with a fever of unknown origin. Subsequently, the diagnosis of ARF can be confirmed with specific serological tests. Serum interleukin-18 levels may be helpful in the differential diagnosis of ARF and sJIA. Although ARF is rare in developed countries, including Japan, early diagnosis and appropriate treatment are important to prevent rheumatic heart disease.

IL-18 polymorphisms and tuberculosis susceptibility: a meta-analysis

Objective

To investigate the association between IL-18 polymorphisms and Tuberculosis(TB).

Materials and methods

We searched PubMed and Embase databases, and conducted a meta-analysis using 4 models. Data were extracted from the studies by two independent reviewers. Statistical analysis was performed using STATA 12.0 software.

Results

Five qualified studies with a total of 1293 TB patients and 1724 controls were included. There was no significant association between the IL-18 -607C>A polymorphism and TB risk in the total population(AA vs CC: OR=1.27,95% CI=0.82–1.96;-CA vs CC:OR=1.06,95% CI=0.89–1.26; Dominant model: OR =1.09, 95% CI =0.83–1.43; Recessive model:OR=1.23, 95% CI=0.92–1.65). For IL-18 -137G>C polymorphism, lack of an association was also found(GG vs CC: OR=1.42,95% CI=0.78–2.58;GC vs CC:OR=1.16,95% CI=0.62–2.16; Dominant model: OR =1.34,95% CI=0.74–2.43;Recessive model:OR=0.96,95%-CI=0.26–3.56).

Conclusion

The present meta-analysis found no evidence for IL-18 -607C>A and -137G>C polymorphisms as risk factors for TB. Further large-scale and well-designed articles are still needed to validate this result.

Elevated Serum Markers of Acute Kidney Injury in Patients With Obstructive Sleep Apnea

STUDY OBJECTIVES

Previous research revealed a positive correlation between endothelial cell injury (indicated by albuminuria) and obstructive sleep apnea (OSA). However, little else has been revealed about acute kidney injury (AKI) in patients with OSA.

METHODS

This prospective study recruited consecutive patients undergoing overnight polysomnography for evaluation of sleep apnea. Patients in whom any major disease or recent infection had been previously diagnosed were excluded. Ultimately, data from 75 patients with apnea-hypopnea indices of 5 or more were analyzed. Baseline values for the urinary albumin-creatinine ratio (UACR), serum levels for three markers of AKI (cystatin C, neutrophil gelatinase-associated lipocalin [NGAL], interleukin-18 [IL-18]), and polysomnography data were recorded and analyzed. Patients then were followed for 6 months of continuous positive airway pressure (CPAP) treatment.

RESULTS

At baseline, UACRs were greater in patients with more severe OSA (P = .005, r = .329). All three serum markers of AKI (cystatin C, NGAL, and IL-18) studied were positively correlated with OSA severity, and two (cystatin C and IL-18) were positively correlated with the frequency of oxygen desaturation during sleep. However, none of the AKI markers had positive correlations with UACR. After 6 months of CPAP treatment, UACR and IL-18 were decreased significantly in patients with good adherence.

CONCLUSIONS

Albuminuria and levels of three serum markers of AKI (cystatin C, NGAL, IL-18) were positively correlated with OSA severity, and good adherence with CPAP treatment decreased albuminuria and interleukin-18 levels. These results may provide additional tools for assessing early renal injury in patients with OSA.

Assessment of Interleukin-18 gene polymorphism and serum levels in oral lichen planus in an Indian population

BACKGROUND

Oral lichen planus (OLP) is a chronic, inflammatory disease with uncertain etiology. The aim of this study was to assess Interleukin-18 (IL-18) gene polymorphism and serum levels in OLP cases of Indian origin and to compare them with a control population of similar background.

METHODS

The assessment of single-nucleotide polymorphisms (SNPs) of IL-18 gene at promoter regions -137(G/C) and -607(C/A) was done in 70 OLP cases and 70 healthy controls using sequence-specific primer-polymerase chain reaction (SSP-PCR). In a subset of this cohort, comprising of 41 OLP cases and 41 controls, serum IL-18 levels were assessed using enzyme-linked immunosorbent assay (ELISA).

RESULTS

Mean serum levels of IL-18 among OLP cases were significantly higher when compared to controls. Genotypic and allelic frequencies of IL-18 at position -137(G/C) showed that GG genotype and allele G was significantly higher in OLP cases, whereas, GC genotype and C allele was high in the control group. Polymorphism of IL-18 at position -607(C/A) showed no significant differences.

CONCLUSIONS

Gene polymorphism at -137GG genotype and allele G seems to be associated with genetic susceptibility to OLP whereas -137GC and allele C may have a protective role against its development. However, our study lacks clear statistical correlation, the differences observed could be caused by sampling problems and the results could not be fully representative of Indian patients with OLP. Further studies are warranted to explore the role of IL-18 genetic polymorphisms in OLP development.

Protein modeling, molecular network and molecular dynamics study of newly sequenced interleukin-18 (IL-18) gene in Mus musculus

Interleukin-18 (IL-18) belongs to the superfamily of IL-1 protein and exerts a pleiotropic pro-inflammatory effect on the body. Generally, this protein is significantly involved in immune defense during infection in cells, but sometimes its anomalous activities produce some inflammatory diseases like rheumatoid arthritis and Crohn's disease. In the present study, the IL-18 gene was isolated from mice and was subsequently cloned and sequenced. Further, the network analysis was carried out to explore the functional role of IL-18 protein in animals. The 3D protein structure of the IL-18 protein was generated and docked with appropriate 3-([3-cholamidopropyl]dimethylammonio)-1-propanesulfonate (CPS) ligand. Later the complex structure of the protein was subjected to molecular dynamics simulation (MDS) for 50 ns to determine the effect of ligand on protein. The network analysis explored the correlation of IL-18 protein with others proteins and their involvement in the different significant pathway to defend the cell from various diseases. As confirmed by MDS, the CPS:IL-18 complex was found to be highly stable. Our results further indicated that CPS ligand has the potential to act as a drug molecule, in future, for counteracting IL-18 activity. To date, no structural details were available for animal IL-18. Hence, the finding of this study will be useful in broadening the horizon towards a better understanding of the functional and structural aspects of IL-18 in animals.

Analytical Value of Cell-Free DNA Based on Alu in Psychiatric Disorders

Psychiatric disorders impose a huge burden on individuals, families, and society. The Alu repeat sequence is a member of the short interspersed nuclear element (SINE) family of mammalian genomes, however, its expression pattern and role in psychiatric disorders is unclear. The current paper aimed at determining the concentrations of Alu in patients with schizophrenia (SZ), major depressive disorder (MDD), and alcohol-induced psychotic disorder (AIPD), and to further define the role and value of Alu as a potential biomarker in psychiatric disorders. In this work, we found that the concentration of Alu was considerably incremented in patients with SZ, and a significant difference existed between patients diagnosed with SZ and MDD or AIPD. ROC analysis also indicated that Alu was effective in the complementary diagnosis of SZ, and differentially diagnosed between SZ patients and patients with MDD or AIPD. In addition, we found a positive relationship between the Alu concentrations and interleukin-1β (IL-1β) in patients with SZ, MDD, and AIPD, and between the concentrations of Alu and interleukin-18 (IL-18) in patients with SZ. Overall, the present work indicates that Alu might be an innovative biomarker for diagnosing psychiatric disorders, and provides the basis for hypotheses about the pathophysiology of psychiatric disorders.