The relationship between diurnal variation of cytokines and symptom expression in mild obstructive sleep apnea

Circ-CIMIRC inhibition alleviates CIH-induced myocardial damage via FbxL4-mediated ubiquitination of PINK1

Obstructive sleep apnea (OSA) is a common sleep disordered breathing diseases that characterized by chronic intermittent hypoxia (CIH). This work aimed to explore the role of circ-CIMIRC in CIH-induced myocardial injury. CIH aggravated myocardial tissue damage in rats. Circ_CIMIRC overexpression promoted apoptosis and reduced the colocalization of Tom20 and Parkin and mitophagy in CIH-treated H9c2 cells. Additionally, FbxL4 interacted with PINK1, FbxL4 silencing reduced PINK1 ubiquitination in H9c2 cells. Two major ubiquitination sites (K319 and K433) were responsible for ubiquitination of PINK1. Circ_CIMIRC promoted FbxL4-mediated ubiquitination and degradation of PINK1. Furthermore, circ_CIMIRC inhibition alleviated the pathological damage, fibrosis and apoptosis of myocardial tissues, reduced oxidative stress in CIH rats. In conclusion, circ_CIMIRC silencing repressed FbxL4-mediated ubiquitination and degradation of PINK1 and then enhanced PINK1/Parkin-mediated mitophagy, thereby alleviating myocardial damage in CIH rats. Thus, circ_CIMIRC may be a potential strategy to alleviate CIH-induced myocardial damage.

Validation of a short version of the Lee fatigue scale in adults living in Norway: a cross-sectional population survey

BACKGROUND

Due to the nature of fatigue, a brief reliable measure of fatigue severity is needed. Thus, the aim of our study was to evaluate a short version of the Lee Fatigue Scale (LFS) in the Norwegian general population.

METHODS

This cross-sectional survey consists of a representative sample from the Norwegian population drawn by The National Population Register in Norway. The study is part of a larger study (NORPOP) aimed at collecting normative data from several questionnaires focused on health in adults living in Norway. Registered citizens between 18 and 94 years of age were randomly selected stratified by age, sex and geographic region. Of the 4971 respondents eligible for the study, 1792 (36%) responded to the survey. In addition to age and sex, we collected responses on a 5-item version of the LFS measuring current fatige severity. The psychometric properties focusing on internal structure and precision of the LFS items were analyzed by a Rasch rating scale model.

RESULTS

Complete LFS scores for analyses were available for 1767 adults. Women had higher LFS-scores than men, and adults < 55 years old had higher scores than older respondents. Our analysis of the LFS showed that the average category on each item advanced monotonically. Two of the five items demonstrated misfit, while the three other items demonstrated goodness-of-fit to the model and uni-dimensionality. Items #1 and #4 (tired and fatigue respectively) showed differential item functioning (DIF) by sex, but no items showed DIFs in relation to age. The separation index of the LFS 3-item scale showed that the sample could be separated into three different groups according to the respondents' fatigue levels. The LFS-3 raw scores correlated strongly with the Rasch measure from the three items. The core dimensions in these individual items were very similarly expressed in the Norwegian language version and this may be a threat to the cultural-related or language validity of a short version of the LFS using these particular items.

CONCLUSIONS

The study provides validation of a short LFS 3-item version for estimating fatigue in the general population.

Evaluation of mandibular advancement device placement based on levels of TNF-alpha in participants with obstructive sleep apnea: A clinical study

STATEMENT OF PROBLEM

Objective assessments of the effect of mandibular advancement device on patients with obstructive sleep apnea are lacking.

PURPOSE

The purpose of this clinical study was to compare levels of serum tumor necrosis factor alpha (TNF-alpha), Epworth Sleepiness Scale score, and Berlin Questionnaire score in patients with mild to moderate obstructive sleep apnea before and after treatment with a mandibular advancement device.

MATERIAL AND METHODS

Twenty participants diagnosed with mild to moderate obstructive sleep apnea based on polysomnography testing were enrolled. A custom nonadjustable mandibular advancement device with 70% mandibular protrusion was provided for each participant for management of the obstructive sleep apnea. Evaluation of TNF-alpha levels was performed before treatment (baseline) and 3 and 6 months after starting mandibular advancement device therapy by using a Human TNF-alpha enzyme-linked immunoassay (ELISA) sandwich kit. The Epworth Sleepiness Scale and Berlin Questionnaire were also filled out by the participants at the same time intervals (α=.05).

RESULTS

A statistically significant decline in the levels of TNF-alpha was observed at 3 and 6 months compared with baseline (P<.001). The Epworth Sleepiness Scale scores showed a statistically significant reduction at 3 and 6 months compared with baseline (P<.001). The risk of obstructive sleep apnea assessed by using the Berlin Questionnaire was found to be significantly reduced at 6 months compared with baseline (P=.001).

CONCLUSIONS

Patients with mild to moderate obstructive sleep apnea showed reduced levels of TNF-alpha and Epworth Sleepiness Scale and Berlin Questionnaire scores when treated with a mandibular advancement device.

Investigating the Role of Serum and Plasma IL-6, IL-8, IL-10, TNF-alpha, CRP, and S100B Concentrations in Obstructive Sleep Apnea Diagnosis

Obstructive sleep apnea (OSA) is a prevalent and underdiagnosed condition associated with cardiovascular diseases, depression, accidents, and stroke. There is an increasing need for alternative diagnostic tools beyond overnight sleep studies that measure the Apnea/Hypopnea Index (AHI). In this single-center, case-control study, we evaluated serum and plasma concentrations of IL-6, IL-8, IL-10, TNF-α, CRP, and S100B in 80 subjects, including 52 OSA patients (27 moderate [15 ≤ AHI ˂ 30], 25 severe [AHI ≥ 30]) and 28 non-OSA controls (AHI 0-5). Participants with OSA showed approximately 2 times higher median concentrations of CRP in plasma, and IL-6 in serum, as well as 1.3 to 1.7 times higher concentrations of TNF-α and IL-8 in plasma compared with the control group. Receiver Operator Characteristic (ROC) curve analysis was performed to evaluate the predictive capabilities of these serum and plasma biomarkers in distinguishing between the OSA and control groups, revealing varying sensitivity and specificity. In summary, in this study, serum and plasma biomarkers CRP, S100B, IL-6, TNF-α, and IL-8 have been shown to be elevated in patients with OSA, correlated positively with disease severity, age, and BMI. These results support the potential role of these biomarkers in diagnosing OSA, supplementing traditional methods such as overnight sleep studies.

Immune response in blood before and after epileptic and psychogenic non-epileptic seizures

Inflammatory processes may provoke epileptic seizures and seizures may promote an immune reaction. Hence, the systemic immune reaction is a tempting diagnostic and prognostic marker in epilepsy. We explored the immune response before and after epileptic and psychogenic non-epileptic seizures (PNES). Serum samples collected from patients with videoEEG-verified temporal or frontal lobe epilepsy (TLE or FLE) or TLE + PNES showed increased interleukin-6 (IL-6) levels in between seizures (interictally), compared to controls. Patients with PNES had no increase in IL-6. The IL-6 levels increased transiently even further within hours after a seizure (postictally) in TLE but not in FLE patients. The postictal to interictal ratio of additionally five immune factors were also increased in TLE patients only. We conclude that immune factors have the potential to be future biomarkers for epileptic seizures and that the heterogeneity among different epileptic and non-epileptic seizures may be disclosed in peripheral blood sampling independent of co-morbidities.

Potential Diagnostic and Monitoring Biomarkers of Obstructive Sleep Apnea-Umbrella Review of Meta-Analyses

Obstructive sleep apnea (OSA) is a prevalent, underdiagnosed disease that imposes a significant impact on the health and wellbeing of patients and a financial burden on individuals, their families, and society. Development of new methods of testing other than an overnight sleep study, such as measurement of serum or plasma biomarkers, may provide an easier diagnostic process to identify patients with OSA and allow earlier initiation of treatment, which might prevent serious comorbidities. We conducted a systematic review and quality assessment of available meta-analyses regarding potential diagnostic and monitoring biomarkers of obstructive sleep apnea. A total of 14 sets of candidate biomarkers displayed differences in levels or concentrations in OSA patients compared to non-OSA controls, and decreased after OSA treatment: CRP, IL-6, TNF-α, Il-8, HCY, ICAM-1, VCAM-1, VEGF, TC, LDLc, HDLc, TG, leptin, MDA, ALT, AST, IGF-1, adiponectin, and cortisol. This review summarizes the evidence for OSA-associated potential biomarkers and demonstrates that the quality of available studies, as measured by AMSTAR2, is often low and associated with a high risk of bias.

Interleukin-8 concentrations in obstructive sleep apnea syndrome: a systematic review and meta-analysis

Interleukin (IL)-8 has been shown to play an important role in obstructive sleep apnea syndrome (OSAS). However, its role in OSAS development is still controversial. This meta-analysis was to explore the correlation between interleukin (IL)-8 concentration and OSAS. Database (from the inception to July 2021) searches on PubMed, Web of Science, Medline, EMBASE, and Cochrane Library were conducted for studies analyzing the correlation between IL-8 concentration and OSAS, regardless of the language of publication. Standardized mean difference (SMD) and 95% confidence intervals (CI) were used to analyze any prospective association between IL-8 concentration and OSAS. A total of 25 eligible studies, including 2301 participants and 1123 controls, were included in this meta-analysis. The included studies evaluating the association between serum IL-8 concentration and OSAS indicated that adults and children with OSAS had elevated serum concentrations of IL-8 compared with controls (SMD = 0.997, 95% CI = 0.437–1.517, P < 0.001; SMD = 0.431, 95% CI = 0.104–0.759, P = 0.01). Categorization of the study population into subgroups according to body mass index, apnea–hypopnea index (AHI), ethnicity, and sample size also showed that individuals with OSAS had elevated serum concentrations of IL-8 compared with controls. Additionally, the results demonstrated that the higher the AHI, higher was the IL-8 concentration. Similar results were observed in the literature on the association between plasma IL-8 concentration and OSAS. This meta-analysis verified that compared with controls, children and adults with OSAS have significantly elevated IL-8 concentrations.

Role of interleukin 8 in depression and other psychiatric disorders

Low grade neuroinflammation has been suggested as one of the underlying mechanisms of many psychiatric diseases as well as cognitive disorders. Interleukin 8 (IL-8), a proinflammatory cytokine produced by many cell types including macrophage and microglia, mainly functions as a neutrophil chemoattractant in the bloodstream. IL-8 is also found in the brain, where it is released from microglia in response to proinflammatory stimuli. In this review, we highlight studies focusing on the role of IL-8 in psychiatric diseases such as major depression, bipolar disorder, schizophrenia, sleep disorder, autism spectrum disorder, anxiety disorders and dementia. Increased peripheral IL-8 levels have been reported in these diseases, particularly in schizophrenic disorder, bipolar disorder, obstructive sleep apnea and autism spectrum disorder. The literature on IL-8 and major depression is inconsistent. IL-8 has been found to be a factor associated with schizophrenic prognosis and therapeutic response, and may affect a wide range of symptomatology. Considering that the exact role of immune alterations is still under research, the success of immune-based therapies in psychiatric diseases is limited for the time being.

Biomarkers in biological fluids in adults with periodontitis and/or obesity: A meta-analysis

Obesity and periodontal diseases have been investigated to be interconnected, but the molecular mechanism underlying this association is still not clear. The aim of this systematic review is to assess the association of serum, salivary and gingival crevicular fluid (GCF) inflammatory markers (IMs), obesity, and periodontitis. Studies that evaluated IM of adults according to obesity status (O) and periodontitis status (P) (O+P+; O-P+; O+P-) were screened on several electronic databases and grey literature up until February 2019. Risk of bias assessment and level of evidence were evaluated through Fowkes and Fulton scale and Grading of Recommendations Assessment, Development and Evaluation (GRADE). Meta-analyses were grouped according to the biological matrix studied (serum/GCF) and groups (O+P+ vs. O−P+/O+P+ vs. O+P−). Out of the 832 studies screened, 21 were considered in qualitative synthesis and 15 in quantitative synthesis (meta-analysis). Although included studies showed mostly “no” or “minor” problems during the quality assessment, GRADE assessment indicated very low to moderate level of evidence based on the question answered. O+P+ adults exhibited significantly higher serum levels of C-reactive protein (CRP), interleukin 6 (IL-6), leptin, and tumor necrosis factor-α (TNF-alpha) and higher resistin GCF levels than O−P+. O+P+ adults showed significantly higher serum levels of IL-6 and leptin and lower adiponectin serum levels than O+P−. Only qualitative information could be obtained of the IM vaspin, omentin-1, chemerin, IL-10, progranulin, MCP-4, IL-1β, and interferon-γ (IFN-γ). Obesity and periodontitis, together or separately, are associated with altered serum and GCF levels of CRP, IL-6, leptin, TNF-alpha, adiponectin, and resistin. It was not possible to evaluate the association between obesity and periodontitis at salivary levels. The role of recently investigated biomarkers as vaspin, omentin-1, chemerin, IL-10, progranulin, MCP-4, IL-1β, and IFN-γ, which can be key points underlying the association between obesity and periodontitis, remains to be further investigated.