A new perspective of frozen shoulder pathology; the interplay between the brain and the immune system

Frozen shoulder (FS), also known as adhesive capsulitis of the shoulder (FS), is a fibrotic inflammatory process of unknown etiology whose main symptoms are pain, stiffness and the loss of joint mobility. These symptoms may be associated with pathologies such as diabetes, Dupuytren's syndrome and the prevalence of today's sedentary lifestyle. This literature review provides an overview of the epidemiology and pathogenesis of this pathology, as well as the mechanisms of lowgrade chronic inflammation and infection, insulin resistance, and omics-science associated with it. We also propose a new hypothesis related to the possibility that the GABAergic system could play a decisive role in the development of frozen shoulder and that therefore diabetes type 1, endocrinological autoimmune disorders and frozen shoulder are connected by the same pathophysiological mechanisms. If that is true, the combined presence of psycho-emotional stress factors and pathogenic immune challenges could be the main causes of frozen shoulder syndrome. Finally, we propose a series of possible intervention strategies based on a multifactorial etiological and mechanistic concept.

Cannabis Cessation, Inflammatory Markers and Schizophrenia

Objective A dysbalance of the immune system in schizophrenia has been largely described but few studies have investigated the impact of cannabis use on inflammatory markers in patients with schizophrenia. The objective of our study was to investigate the impact of cannabis use on high-sensitivity C-reactive protein (hsCRP), fibrinogen levels and leucocytic formula in patients with schizophrenia. Methods: Thirty-eight acutely ill inpatients with schizophrenia were included. Patient hsCRP, fibrinogen levels, leukocytic formula and urinary cannabis were measured at baseline and after four weeks of treatment. Results: After four weeks of cannabis cessation (as confirmed by urinary tests), we found an increase of hsCRP level (p = .016) and lymphocytes (p = .03) in consumers patients whereas no difference was observed in non-consumers patients. As compared to non-consumers patients with schizophrenia, consumers had lower levels of hsCRP (p = .045). Finally, a negative correlation was found between the PANSS score evolution (between baseline and 4 weeks) and baseline hsCRP level. Conclusions: In our study, cannabis cessation raises inflammatory markers though improving clinical symptoms. The investigation and the understanding of interactions between cannabis use and inflammatory markers in patients with schizophrenia is of importance and could in the future be a new target for treatment of psychiatric symptoms linked to inflammation.

Potential Nutrients from Natural and Synthetic Sources Targeting Inflammaging-A Review of Literature, Clinical Data and Patents

Inflammaging, the steady development of the inflammatory state over age is an attributable characteristic of aging that potentiates the initiation of pathogenesis in many age-related disorders (ARDs) including neurodegenerative diseases, arthritis, cancer, atherosclerosis, type 2 diabetes, and osteoporosis. Inflammaging is characterized by subclinical chronic, low grade, steady inflammatory states and is considered a crucial underlying cause behind the high mortality and morbidity rate associated with ARDs. Although a coherent set of studies detailed the underlying pathomechanisms of inflammaging, the potential benefits from non-toxic nutrients from natural and synthetic sources in modulating or delaying inflammaging processes was not discussed. In this review, the available literature and recent updates of natural and synthetic nutrients that help in controlling inflammaging process was explored. Also, we discussed the clinical trial reports and patent claims on potential nutrients demonstrating therapeutic benefits in controlling inflammaging and inflammation-associated ARDs.

A Comprehensive View of Frozen Shoulder: A Mystery Syndrome

Frozen shoulder is a common epidemiological affliction. Data acquired from people who suffer from this type of damage in other joints such as the hip, wrist and ankle also exist; although these syndromes are less common. Treatment for frozen shoulder is primarily physical (physiotherapy, manual therapy), secondary medical (corticosteroid injections) and finally surgical but with limited success. The difficulty in treating this type of condition successfully lies in the lack of knowledge about the risk factors involved and the pathophysiology underlying this mysterious syndrome. This review gives an overview of the current scientific position of frozen shoulder in terms of evolutionary factors, etiology, the different mechanisms of action involved, current treatment options and other possible interventions based on recent discoveries of pathophysiological mechanisms. The overall objective is to clarify several unknown aspects of a syndrome that affects up to 5% of the world's population.

Long term pronostic value of suPAR in chronic heart failure: reclassification of patients with low MAGGIC score

OBJECTIVES

Inflammation is a hallmark of heart failure (HF) and among inflammatory biomarkers, the most studied remains the C-reactive protein (CRP). In recent years several biomarkers have emerged, such as sST2 and soluble urokinase-type plasminogen activator receptor (suPAR). This study set out to examine the relative importance of long-time prognostic strength of suPAR and the potential additive information on patient risk with chronic HF in comparison with pronostic value of CRP and sST2.

METHODS

Demographics, clinical and biological variables were assessed in a total of 182 patients with chronic HF over median follow-up period of 80 months. Inflammatory biomarkers (i.e., CRP, sST2, and suPAR) were performed.

RESULTS

In univariate Cox regression analysis age, NYHA class, MAGGIC score and the five biomarkers (N-terminal pro brain natriuretic peptide [NT-proBNP], high-sensitive cardiac troponin T [hs-cTnT], CRP, sST2, and suPAR) were associated with both all-cause and cardiovascular mortality. In the multivariate model, only NT-proBNP, suPAR, and MAGGIC score remained independent predictors of all-cause mortality as well as of cardiovascular mortality. Risk classification analysis was significantly improved with the addition of suPAR particularly for all-cause short- and long-term mortality. Using a classification tree approach, the same three variables could be considered as significant classifier variables to predict all-cause or cardiovascular mortality and an algorithm were reported. We demonstrated the favorable outcome associated with patients with a low MAGGIC score and a low suPAR level by comparison to patients with low MAGGIC score but high suPAR values.

CONCLUSIONS

The main findings of our study are (1) that among the three inflammatory biomarkers, only suPAR levels were independently associated with 96-month mortality for patients with chronic HF and (2) that an algorithm based on clinical score, a cardiomyocyte stress biomarker and an inflammatory biomarker could help to a more reliable long term risk stratification in heart failure.

Endurance Exercise Mitigates Immunometabolic Adipose Tissue Disturbances in Cancer and Obesity

Adipose tissue is considered an endocrine organ whose complex biology can be explained by the diversity of cell types that compose this tissue. The immune cells found in the stromal portion of adipose tissue play an important role on the modulation of inflammation by adipocytokines secretion. The interactions between metabolic active tissues and immune cells, called immunometabolism, is an important field for discovering new pathways and approaches to treat immunometabolic diseases, such as obesity and cancer. Moreover, physical exercise is widely known as a tool for prevention and adjuvant treatment on metabolic diseases. More specifically, aerobic exercise training is able to increase the energy expenditure, reduce the nutrition overload and modify the profile of adipocytokines and myokines with paracrine and endocrine effects. Therefore, our aim in this review was to cover the effects of aerobic exercise training on the immunometabolism of adipose tissue in obesity and cancer, focusing on the exercise-related modification on adipose tissue or immune cells isolated as well as their interaction.

Polarization of Low-Grade Inflammatory Monocytes Through TRAM-Mediated Up-Regulation of Keap1 by Super-Low Dose Endotoxin

Subclinical endotoxemia [low levels of bacterial endotoxin (LPS) in the blood stream] has been correlated with chronic inflammatory diseases, with less-understood mechanisms. We have previously shown that chronic exposure to super low doses of LPS polarizes monocytes/macrophages to a pro-inflammatory state characterized by up-regulation of pro-inflammatory regulators such as p62 and simultaneous down-regulation of anti-inflammatory/resolving regulators such as Nrf2. Building upon this observation, here we show that chronic exposure to super-low doses of LPS leads to accumulation of the Nrf2-inhibitory protein Keap1 in murine monocytes. This is accompanied by increases of p62 and MLKL, consistent with a disruption of autolysosome function in polarized monocytes challenged by super-low dose LPS. Monocytes subjected to persistent super-low dose LPS challenge also accumulate higher levels of IKKβ. As a consequence, SLD-LPS challenge leads to an inflammatory monocyte state represented by higher expression of the inflammatory marker Ly6C as well as lower expression of the anti-inflammatory marker CD200R. Further analysis revealed that Keap1 levels are significantly enriched in the Ly6C^hi pro-inflammatory monocyte population. Finally, we show that the TLR4 signaling adaptor TRAM is essential for these effects. Together our study provides novel insight into signaling mechanisms behind low-grade inflammatory monocyte polarization unique to chronic super-low dose LPS exposure.

Mechanisms Involved in Childhood Obesity-Related Bone Fragility

Childhood obesity is one of the major health problems in western countries. The excessive accumulation of adipose tissue causes inflammation, oxidative stress, apoptosis, and mitochondrial dysfunctions. Thus, obesity leads to the development of severe co-morbidities including type 2 diabetes mellitus, liver steatosis, cardiovascular, and neurodegenerative diseases which can develop early in life. Furthermore, obese children have low bone mineral density and a greater risk of osteoporosis and fractures. The knowledge about the interplay bone tissue and between adipose is still growing, although recent findings suggest that adipose tissue activity on bone can be fat-depot specific. Obesity is associated to a low-grade inflammation that alters the expression of adiponectin, leptin, IL-6, Monocyte Chemotactic Protein 1 (MCP1), TRAIL, LIGHT/TNFSF14, OPG, and TNFα. These molecules can affect bone metabolism, thus resulting in osteoporosis. The purpose of this review was to deepen the cellular mechanisms by which obesity may facilitate osteoporosis and bone fractures.

Mediterranean diet, dietary polyphenols and low grade inflammation: results from the MOLI-SANI study

Low grade inflammation is characterized by raised concentrations of inflammatory markers in the absence of any overt symptoms and is recognized as a risk factor for a number of chronic diseases including cancer, cardiovascular, cerebrovascular and neurodegenerative diseases. Many studies suggest that low grade inflammation is mitigated by health promoting behaviours such as healthy eating patterns, physical activity, body weight maintenance and tobacco cessation. To date, large scale studies were mainly focused on circulating markers and little evidence is available on cellular biomarkers. The MOLI-SANI study is a prospective cohort study that has recruited 24 325 men and women aged ≥35 years from the general population of the Molise Region, a Southern Italian area, with the purpose of investigating genetic and environmental risk/protection factors for cardiovascular and cerebrovascular disease and cancer. Within this cohort, a composite score of low grade inflammation based on the use of plasmatic (C-reactive protein) and cellular (leukocyte and platelet counts and granulocyte : lymphocyte ratio) biomarkers has been proposed and validated. This score accounts for all possible synergistic effects of such inflammatory markers, thus overcoming any potential bias linked to the multi-collinearity of these variables. Of notice, the MOLI-SANI study was the first to address the relationship between the traditional Mediterranean diet and platelet and leucocyte counts as emerging cellular biomarkers of low grade inflammation. The present review paper will discuss the main findings derived from the MOLI-SANI study on the association of low grade inflammation with a Mediterranean eating pattern, with a particular emphasis on the associated dietary polyphenols.

High-sensitive C-Reactive Protein as a Marker for Inflammation in Irritable Bowel Syndrome

BACKGROUND

Recent studies demonstrated low-grade inflammation in patients with irritable bowel syndrome (IBS). However, these studies have been relatively small and do not enable examination of this factor in different subtypes of IBS and the possibility of confounding effects of comorbidities that may be associated with inflammatory responses.

GOALS

To investigate the association between high-sensitive C-reactive protein (hs-CRP) and the diagnosis of IBS, IBS subtypes, symptoms' severity, and IBS-associated comorbidities.

STUDY

This cross-sectional study uses data from a large matched case-control study of IBS subjects and healthy controls (HC). hs-CRP levels were measured in all subjects. IBS diagnosis was determined by Rome III criteria, negative screening blood tests, and normal colonoscopy. Subjects were evaluated for IBS severity and associated pain and psychological comorbidities.

RESULTS

A total of 242 IBS patients and 244 HC were studied. Median hs-CRP levels in the IBS group were significantly higher than in HC (1.80; interquartile range, 0.7 to 4.04 mg/L vs. 1.20, interquartile range, 0.5 to 2.97 mg/L respectively, P<0.006). Levels were highest in IBS-D patients with greater disease severity. Hs-CRP levels mildly correlated with symptoms severity (r=0.169, P=0.009); this correlation was stronger for the IBS-D patients (r=0.27, P=0.006). IBS was a significant independent predictor (P=0.025) for higher hs-CRP levels, whereas other pain and psychological comorbidities were not.

CONCLUSIONS

Given these observations of cross-sectional differences in hs-CRP between IBS subtypes and severity, independent of pain and comorbidities, more research is needed to explore a possible role of low-grade inflammation in the pathogenesis and/or clinical presentation of IBS.

Exercise reduced inflammation: but for how long after training?

BACKGROUND

Previous studies have reported that obese people with trisomy 21 suffer from low-grade systemic inflammation. A recent study has found that aerobic training reduced inflammation in obese women with Down syndrome. To the best of our knowledge, the study reported in this paper is the first to determine for how long these effects were maintained after completion of the programme.

METHODS

Twenty premenopausal obese women (18-30 years old) with Down syndrome volunteered for this study. Eleven were randomly assigned to the intervention group and performed a 10-week aerobic training programme, 3 sessions per week, consisting of warming-up followed by treadmill exercise (30-40 min) at a work intensity of 55-65% of peak heart rate and a cooling-down period. The control group included 9, age, sex and BMI matched women with Down syndrome that did not perform any training programme. Fat mass percentage and distribution were measured. Plasma level of IL-6 and high-sensitive C-reactive protein (hs-CRP) were monitored. Time-course changes for these outcomes were assessed at pre- and post-intervention. Further, they were re-evaluated at 1, 3 and 6 months after completion of the programme.

RESULTS

Three months after completion of the programme, plasma levels of IL-6 and hs-CRP were significantly increased. Up to 6 months later, both fat mass percentage and waist circumference (WC) were significantly increased. Furthermore, physical fitness was also impaired in the intervention group. No changes were observed in the control group.

CONCLUSION

A 3-month detraining period significantly impaired chronic inflammation in obese women with DS.

Higher serum soluble receptor for advanced glycation end product levels and lower prevalence of metabolic syndrome among Japanese adult men: a cross-sectional study

BACKGROUND

Although several studies showed that decreased soluble receptor for advanced glycation end products (sRAGE) is associated with metabolic syndrome (MetS), inflammation level has not been considered, even though ligand-RAGE interaction induces inflammation. The objective of the study was to determine the association between sRAGE and MetS among Japanese adult in a cross-sectional survey, taking the level of low grade inflammation into consideration.

METHODS

Serum soluble RAGE (sRAGE) were measured in 712 men and 176 women aged 30-83 years with serum C-reactive protein (hsCRP) concentration below 3 mg/L. MetS was defined using the criteria of the American Heart Association Scientific Statements of 2009.

RESULTS

After multivariable adjustment, among men, higher sRAGE levels were associated with lower odds of MetS as well as central obesity and elevated blood pressure. Comparing the extreme tertiles of sRAGE, odds ratios (95% confidence interval) were 0.58 (0.36-0.95; P for trend = 0.001) for MetS; 0.41 (0.25-0.52; P for trend < 0.001) for central obesity; and 0.45 (0.29-0.70; P for trend < 0.001) for elevated blood pressure. Moreover, participants were categorized according to their median hsCRP and sRAGE values. Men in the higher hsCRP/higher sRAGE category had a 40% lower odds ratio for MetS than those in the higher hsCRP/lower sRAGE category (P = 0.031). Among women, there was no association between sRAGE levels and the prevalence of MetS.

CONCLUSIONS

Higher circulating RAGE concentrations were associated with lower prevalence of MetS and its components among Japanese men.

Molecular mechanisms responsible for the selective and low-grade induction of proinflammatory mediators in murine macrophages by lipopolysaccharide

Low-dose endotoxemia is prevalent in humans with adverse health conditions, and it correlates with the pathogenesis of chronic inflammatory diseases such as atherosclerosis, diabetes, and neurologic inflammation. However, the underlying molecular mechanisms are poorly understood. In this study, we demonstrate that subclinical low-dose LPS skews macrophages into a mild proinflammatory state, through cell surface TLR4, IL-1R-associated kinase-1, and the Toll-interacting protein. Unlike high-dose LPS, low-dose LPS does not induce robust activation of NF-κB, MAPKs, PI3K, or anti-inflammatory mediators. Instead, low-dose LPS induces activating transcription factor 2 through Toll-interacting protein-mediated generation of mitochondrial reactive oxygen species, allowing mild induction of proinflammatory mediators. Low-dose LPS also suppresses PI3K and related negative regulators of inflammatory genes. Our data reveal novel mechanisms responsible for skewed and persistent low-grade inflammation, a cardinal feature of chronic inflammatory diseases.