Caspase-1 and interleukin-18 in children with post infectious bronchiolitis obliterans: a case-control study.

The exact immunological mechanisms of post infectious bronchiolitis obliterans (PIBO) in childhood are not fully known. It has been shown that the inflammasome and IL-18 pathway play important roles in the pathogenesis of lung fibrosis. We aimed to investigate the role of caspase-1, IL-18, and IL-18 components in PIBO. From January to May 2020, children with PIBO, children with history of influenza infection without PIBO, and healthy children were asked to participate in the study in three pediatric pulmonology centers. Serum caspase-1, IL-18, IL-18BP, IL-18R, and INF-γ levels were measured by ELISA and compared between the 3 groups. There were 21 children in the PIBO group, 16 children in the influenza group, and 39 children in the healthy control group. No differences in terms of age and gender between the 3 groups were found. IL-18 and IL-18BP levels were higher in the healthy control group (p = 0.018, p = 0.005, respectively). IL-18R was higher in the PIBO group (p = 0.001) and caspase-1 was higher in the PIBO and influenza group than the healthy control group (p = 0.002). IFN-γ levels did not differ between the 3 groups. IL-18BP/IL-18 was higher in the influenza group than the PIBO group and the healthy control group (p = 0.003). CONCLUSIONS: Caspase-1 level was increased in patients with PIBO which suggests that inflammasome activation may have a role in fibrosis; however, IL-18 level was found to be low. Mediators other than IL-18 may be involved in the inflammatory pathway in PIBO. Further immunological studies investigating inflammasome pathway are needed for PIBO with chronic inflammation. WHAT IS KNOWN: • Post infectious bronchiolitis obliterans (PIBO) is a rare, severe chronic lung disease during childhood which is associated with inflammation and fibrosis which lead to partial or complete luminal obstruction especially in small airways. • The exact immunological mechanisms of PIBO in childhood are not fully known. WHAT IS NEW: • Inflammasome activation persists even years after acute infection and may play a role in fibrosis in PIBO. • Mediators other than IL-18 may be involved in these inflammatory pathway.

Effect of vitamin D on myocardial remodeling and inflammatory status in children with congenital heart disease.

BACKGROUND: Vitamin D insufficiency is a common public health problem that is often unrecognized in children with congenital heart disease, and is not generally evaluated at congenital heart disease (CHD) follow-up. Recent studies have suggested that inadequate vitamin D status may have an adverse effect on cardiovascular health. This study investigates the relationship between vitamin D levels and hemodynamic parameters in children with CHD. METHODS: Included in the study 40 patients (25 females, 15 males) with CHD, who were evaluated for Ross heart failure score, vitamin D, parathyroid hormone (PTH), calcium, phosphorus, alkaline phosphatase (ALP), whole blood count (WBC) and echocardiographic measurements, and all measurements were repeated in the third month of the therapy. RESULTS: The mean vitamin D level was 16.4 ± 6.6 ug/L before and 27.5 ± 9.9 µg/L in the third month of therapy, while the mean PTH level was 53.3 ± 34.9 pg/mL before and 43.8 ± 21.4 pg/mL in the third month of therapy. The mean WBC was 8084 ± 2324/µL before and 7378±1893/µL in the third month of the therapy, and the mean platelet (PLT) count was 280,897 ± 80,119/µL before and 307,179 ± 60,202/µL in the third month of the therapy. The mean ejection fraction (EF) was 64% ± 7.2% before and 66.7% ± 6.2% in the third month of therapy, while the right ventricle (RV) myocardial performance index (MPI) was 32.1% ± 6.7% before and 28.9% ± 6.5% in the third month of the therapy. IL10 level was increased in four patients in the third month of therapy. A statistically significant decrease in PTH level and WBC, and an increase in PLT number and IL-10 level were detected by the therapy. Furthermore, echocardiographic findings revealed a statistically significant increase in EF and a decrease in RVMPI attributable to the therapy. DISCUSSION: The decreased levels of PTH, which is a proinflammatory marker, the increases in IL-10, which is an antiinflammatory cytokine, and the decreases in the number of WBC resulting from vitamin D treatment demonstrate the antiinflammatory effects of vitamin D. An improvement in EF means improvement in left ventricular contractility, while a decrease in RV MPI has been shown to improve the systolic and diastolic function of the right ventricle. These results suggest that vitamin D therapy has a positive effect on the heart, and so vitamin D levels should be evaluated during the routine follow-up of congenital heart disease.

Iron homeostasis is altered in response to hypoxia and hypothermic preconditioning in brain glial cells

Background/aim: Altered iron metabolism is one of the pathophysiological mechanisms occurring during hypoxic injuries in the central nervous system. Proper homeostasis of cellular iron is regulated by iron import, storage, and export proteins that prevent excess iron overload or iron starvation in cells. Therapeutic hypothermia is an approved treatment for hypoxic ischemia in newborns, but the underlying molecular mechanism is still unknown. We studied the effects of hypoxia, preceded with preconditioning, on the iron homeostasis of glial cells, known as a major actor in the inflammatory process during perinatal brain injury. Materials and methods: Primary microglia and astrocytes in culture were exposed to 12 h of hypoxia with or without mild hypothermic preconditioning. The mRNA expression was assessed using qPCR. Iron accumulation was visualized via modified Perl's histochemistry. Cytokine levels in cell cultures were measured using ELISA. Results: Hypothermic preconditioning enhanced microglial viability, which previously was decreased in both cell types due to hypoxia. Hypoxia increased iron accumulation in the mixed glial cells and in ferritin expression in both microglia and astrocytes. Hypotermic preconditioning decreased the elevated ferritin-light chain expression significantly in microglia. Iron importer proteins, DMT1 and TfR1, both increased their mRNA expression after hypoxia, and hypothermic preconditioning continued to support the elevation of DMT1 in both glial cell types. Ferroportin expression increased as a survival factor of the glial cell following hypoxia. Hypothermic preconditioning supported this increase in both cell types and was especially significant in astrocytes. IL-10 levels were prominently increased in cell culture after hypothermic preconditioning. Conclusion: The data suggest that hypothermic preconditioning affects cellular iron homeostasis by regulating the storage and transfer proteins of iron. Regulation of the cellular iron traffic may prevent glial cells from experiencing the detrimental effects of hypoxia-related inflammation.

Plasma human leukocyte antigen-G (HLA-G) in patients with thyroid cancer

Background/aim: A number of tumor markers detected in the serum or pathological specimens using immunohistochemical methods are used for early detection of malignancies and postoperative follow-up. Human leukocyte antigen-G (HLA-G) is a nonclassic HLA class I molecule. Recent studies suggested a relationship between HLA-G positivity and the stage or the phenotype of the malignancy. In this study, the relationship between serum HLA-G positivity and thyroid cancer was investigated. Materials and methods: Fifty patients with thyroid cancer and 45 healthy volunteers were included in this study. Serum HLA-G levels were measured using ELISA. Results: HLA-G was positive in only 3 out of 50 patients with thyroid cancer (2 papillary, 1 follicular type). On the other hand, HLA-G was positive in 20 out of 45 healthy subjects (P < 0.001). The prevalence of detectable levels of serum HLA-G was independent of sex and age in the whole study population. No correlation was found between serum HLA-G value and thyroid hormone profile, neither in papillary thyroid cancer nor follicular thyroid cancer patients. Conclusion: In this study, serum HLA-G was significantly less common in patients with thyroid cancer than in healthy controls.

Cellular iron storage and trafficking are affected by GTN stimulation in primary glial and meningeal cell culture.

A well-balanced intracellular iron trafficking in glial cells plays a role in homeostatic processes. Elevated intracellular iron triggers oxidative stress and cell damage in many neurological disorders, including migraine. This study aimed to investigate the effects of glyceryl trinitrate (GTN), on cellular iron homeostasis, matrixmetalloproteinase (MMP)-9, and calcitonin gene related peptide (CGRP) receptor (CRLR/CGRPR1) production in microglia, astrocyte, and meningeal cell cultures. Primary glial and meningeal cells in culture were exposed to GTN for 24 h. Messenger RNA expression was assessed using qPCR. Iron accumulation was visualized via modified Perl's histochemistry. MMP-9 levels in cell culture supernatants were measured using ELISA. Ferritin and CRLR/CGRPR1 proteins were visualized via immunofluorescence staining. Nitric oxide production increased significantly with GTN in meningeal and glial cells. GTN significantly increased the expression of the storage protein ferritin for all three cell types, but ferritin-L for meningeal cells and microglia. Iron trafficking associated with the efflux protein ferroportin and influx protein divalent metal transporter (DMT)1 was affected differently in all three cell types. MMP-9 expression was increased in astrocytes. GTN stimulation increased both CRLR/CGRPR1 expression, and immunostaining was apparent in microglia and meningeal cells. This study showed for the first time that GTN modulates intracellular iron trafficking regulated by storage and transport proteins expressed in meningeal cells and glia. CRLR/CGRPR1 expression might be related to altered iron homeostasis and they both may stimulate nociceptive pathways activated in migraine. These molecules expressed differently in glial and meningeal cells in response to GTN may bring not only new targets forward in treatment but also prevention in migraine.

Comparison of hippocampal interleukin-6 immunoreactivity after exhaustive exercise in both exercise-trained and untrained rats.

BACKGROUND/AIM: Exhaustive exercise is a strong stress factor and can impact cytokine production in the brain. Interleukin-6 (IL-6) is produced in greater amounts than any other cytokine in response to exercise, and its effects are closely related to both exercise duration and intensity. In this study, we measured the differences between the amount of IL-6 reactivity of the hippocampus after an exhaustive session ofrunning in long-term exercise-trained and untrained rats. MATERIALS AND METHODS: The exercise-trained group ran on a treadmill for 12 weeks. Both groups were forced to run until exhaustion. Each group of rats was sacrificed immediately, 1 day, or 3 days after exhaustion and the brains were evaluated for IL-6 immunoreactivity in the hippocampus. RESULTS: Hippocampal IL-6 immunoreactivity was absent in controls, mild to severe in untrained rats, and weak to mild in long-term-trained rats. The most prominent increase in IL-6 was observed in the untrained rats sacrificed 1 day after exhaustion. CONCLUSION: Exercise to exhaustion resulted in increased IL-6 levels in brain slices in both groups of rats, but long-term exercise training protected the hippocampus from exposure to an extreme increase in IL-6. The immediate effects of these cytokine levels were observed 1 day after exhaustion.