Nonthyroidal illness syndrome: is it far away from Crohn's disease?

Thyroid allostasis in drug-free affective disorder patients

AIM

To assess the thyroid allostasis in drug-free patients with affective disorder.

METHODS

Patients with major depressive disorder or bipolar disorder as drug-free, defined as those without psychiatric drugs exposure for at least 4 months before admission, from a tertiary hospital were recruited in this cross-sectional study. The primary outcomes were "structure parameters of thyroid homeostasis", which include "thyroid's secretory capacity" (SPINA-GT), "sum step-up activity of deiodinases" (SPINA-GD), the ratio of total to free thyroxine and "thyroid homeostasis central set point" (TSH index and "thyroid feedback quantile-based index" [TFQI]), calculated by TSH and thyroid hormones measured at admission. A healthy population and non-affective psychiatric disorder (schizophrenia) from the same catchment area were recruited as two comparison groups.

RESULTS

A total of 1263 cases of major depressive disorder, 1619 cases of bipolar disorder, 1186 cases of schizophrenia, and 162 healthy controls were included in the study. Compared to healthy control, GD and ratio of total to free thyroxine were lower in affective disorders. Bipolar with mania episode had higher GT than bipolar with depressive episode and major depressive disorder (median level at 3.70 vs. 3.04 and 3.03, respectively). Compared with healthy control, schizophrenia had higher TSH index and TFQI, but no increase in these parameters in major depressive disorder and bipolar disorder.

CONCLUSION

Affective disorders have a unique profile of thyroid allostasis with impaired step-up deiodinase activity and reduced serum protein binding of thyroid hormones, but no change in thyroid homeostasis central set point. Mania episode may be associated with higher thyroid secretory capacity.

Dietary Application of the Microalga Lobosphaera incisa P127 Reduces Severity of Intestinal Inflammation, Modulates Gut-Associated Gene Expression, and Microbiome in the Zebrafish Model of IBD

SCOPE

Microalgae are an emerging nutritional resource of biomolecules with potential to alleviate gut inflammation. The study explores the anti-inflammatory and immunomodulatory potential of the microalga Lobosphaera incisa P127, which accumulates a rare omega-6 LC-PUFA dihomo-ɣ-linolenic acid (DGLA) under nitrogen starvation. The therapeutic potential of dietary supplementation with P127 is investigated in the zebrafish model of IBD (TNBS-induced colitis).

METHODS AND RESULTS

Guts are sampled from zebrafish fed experimental diets for 4 weeks, before and 24 h after TNBS challenge. Diets containing 15% non-starved (Ns) and 7.5% and 15% N-starved (St) algal biomass significantly attenuate the severity of gut injury and goblet cell depletion. In contrast, diets containing 7.5% Ns and DGLA ethyl ester have no effect on gut condition. Fish fed 15% St, high-DGLA biomass, have the fewest individuals with pathological alterations in the gut. Dietary inclusion of Ns and St distinctly modulates gut-associated expression of the immune and inflammatory genes. Fish fed 15% Ns biomass display a coordinated boost in immune gene expression and show major changes in the gut microbiome prior challenge.

CONCLUSION

Dietary inclusion of L. incisa biomass at two physiological states, ameliorates TNBS-induced gut inflammation, suggesting the synergistic beneficial effects of biomass components not limited to DGLA.

Nonthyroidal Illness Syndrome in Patients With Short-Bowel Syndrome

BACKGROUND

Nonthyroidal illness syndrome (NTIS) is prevalent in critical illness and is associated with poor outcomes. However, only few studies have focused on the relationship between NTIS and short-bowel syndrome (SBS). The aim of this study was to investigate the prevalence, etiology, and prognosis of NTIS and its correlation with clinical variables in adult patients with SBS.

METHODS

Sixty-one eligible adults diagnosed with SBS, from December 2016 to December 2018, were retrospectively identified from a prospectively maintained database. Demographic and clinical characteristics (including thyroid hormones and nutrition variables) were evaluated for each participant.

RESULTS

The prevalence of NTIS in adults with SBS was 52.5%. Patients with NTIS tended to have a longer duration of hospital stay and poor survival, but the results were not significant. A decreased, standard thyroid-stimulating hormone index and sum activity of deiodinases and an increased secretory capacity by the thyroid were observed in the NTIS group. Receiver operating characteristic curve analysis showed that insulin-like growth factor-1 (IGF-1) had better performance for distinguishing NTIS from patients with euthyroidism, with an area under the curve of 0.862 (cutoff, 101.0; sensitivity, 0.813; and specificity, 0.800).

CONCLUSIONS

NTIS is a common complication in adult patients with SBS. Patients with NTIS tend to have a worse nutrition status and poor prognosis. A potential pituitary thyrotroph dysfunction and hypodeiodination condition may play a role in the pathophysiology of NTIS in SBS. Furthermore, IGF-1 is a meaningful predictor for distinguishing NTIS from euthyroid.

Infliximab Therapy Could Decrease the Risk of the Development of Thyroid Disorders in Pediatric Patients With Crohn's Disease

Autoimmune diseases, including autoimmune thyroid diseases (AITDs), may be associated with Crohn's disease (CD). Taking into consideration the role of tumor necrosis factor alpha (TNF-alpha) in the immune-mediated inflammation that underlies both diseases, we evaluated an ultrasound of thyroid gland in pediatric CD patients, naïve, and treated with infliximab (IFX), an anti-TNF-alpha antibody, to assess the risk for AITD and evaluated the usefulness of ultrasonography to diagnose AITD in patients with CD. Sixty-one patients with CD were enrolled in the study, including 36 patients (mean age 14.5 ± 3.5 years) treated with IFX (IFX group) for a mean of 13.9 ± 16.6 months and 25 patients (mean age 14.7 ± 2.3 years) who never received anti-TNF-alpha therapy (control group). An ultrasound examination of the thyroid gland was performed; thyroid function tests and thyroid antibodies were assessed. We found 10-times higher prevalence of decreased thyroid echogenicity in CD and IFX-naive patients compared to IFX-treated group [a significant reduction in thyroid echogenicity in 1/36 (2.8%) patients receiving IFX compared to 7/25 (28%) patients naive to biologic therapy]. The latter showed significantly lower thyroid-stimulating hormone (TSH) levels (p = 0.034) and higher levels of thyroid antibodies (p = 0.042) in comparison to control. Our data suggest the protective role of IFX therapy in the development of thyroid disorders and indicate the usefulness of thyroid ultrasound to identify the risk of probable AITD in pediatric patients with CD.

Complete genome sequence of the Bifidobacterium animalis subspecies lactis BL3, preventive probiotics for acute colitis and colon cancer

We report the genome sequence of Bifidobacterium animalis subspecies lactis BL3, which has preventive properties on acute colitis and colon cancer. The genome of BL3, which was isolated from Korean faeces, consisted of a 1 944 323 bp size single chromosome, and its G+C content was 60.5%. Genome comparison against the closest Bifidobacterium animalis strain revealed that BL3 had particularly different regions of four areas encoding flavin-nucleotide-binding protein, transposase, multidrug ABC transporter and ATP binding protein.

Thyroid Allostasis-Adaptive Responses of Thyrotropic Feedback Control to Conditions of Strain, Stress, and Developmental Programming

The hypothalamus-pituitary-thyroid feedback control is a dynamic, adaptive system. In situations of illness and deprivation of energy representing type 1 allostasis, the stress response operates to alter both its set point and peripheral transfer parameters. In contrast, type 2 allostatic load, typically effective in psychosocial stress, pregnancy, metabolic syndrome, and adaptation to cold, produces a nearly opposite phenotype of predictive plasticity. The non-thyroidal illness syndrome (NTIS) or thyroid allostasis in critical illness, tumors, uremia, and starvation (TACITUS), commonly observed in hospitalized patients, displays a historically well-studied pattern of allostatic thyroid response. This is characterized by decreased total and free thyroid hormone concentrations and varying levels of thyroid-stimulating hormone (TSH) ranging from decreased (in severe cases) to normal or even elevated (mainly in the recovery phase) TSH concentrations. An acute versus chronic stage (wasting syndrome) of TACITUS can be discerned. The two types differ in molecular mechanisms and prognosis. The acute adaptation of thyroid hormone metabolism to critical illness may prove beneficial to the organism, whereas the far more complex molecular alterations associated with chronic illness frequently lead to allostatic overload. The latter is associated with poor outcome, independently of the underlying disease. Adaptive responses of thyroid homeostasis extend to alterations in thyroid hormone concentrations during fetal life, periods of weight gain or loss, thermoregulation, physical exercise, and psychiatric diseases. The various forms of thyroid allostasis pose serious problems in differential diagnosis of thyroid disease. This review article provides an overview of physiological mechanisms as well as major diagnostic and therapeutic implications of thyroid allostasis under a variety of developmental and straining conditions.

The Thyroid Hormone Inactivating Enzyme Type 3 Deiodinase is Present in Bactericidal Granules and the Cytoplasm of Human Neutrophils

Neutrophils are important effector cells of the innate immune system. Thyroid hormone (TH) is thought to play an important role in their function. Intracellular TH levels are regulated by the deiodinating enzymes. The TH-inactivating type 3 deiodinase (D3) is expressed in infiltrating murine neutrophils, and D3 knockout mice show impaired bacterial killing upon infection. This suggests that D3 plays an important role in the bacterial killing capacity of neutrophils. The mechanism behind this effect is unknown. We aimed to assess the presence of D3 in human neutrophils, and determine its subcellular localization using confocal and electron microscopy, because this could give important clues about its function in these cells. D3 appeared to be present in the cytoplasm and in myeloperoxidase containing azurophilic granules and as well as lactoferrin containing specific granules within human neutrophils. This subcellular localization did not change upon activation of the cells. D3 is observed intracellularly during neutrophil extracellular trap formation, followed by a reduction of D3 staining after release of the neutrophil extracellular traps into the extracellular space. At the transcriptional level, human neutrophils expressed additional essential elements of TH metabolism, including TH transporters and TH receptors. Here, we demonstrate the presence and subcellular location of D3 in human neutrophils for the first time and propose a model, in which D3 plays a role in the bacterial killing capacity of neutrophils either through generation of iodide for the myeloperoxidase system or through modulation of intracellular TH bioavailability.

Circadian rhythm abnormalities - Association with the course of inflammatory bowel disease

Crohn's disease (CD) and ulcerative colitis (UC) are the main representatives of inflammatory bowel diseases (IBD), a group of chronic, immune system-mediated inflammatory diseases of the gastrointestinal (GI) tract. The pathogenesis of the intestinal lesions in IBD is not entirely identified and understood: excessive activation of the immune system may come as a result of the interaction of various environmental and infectious factors, genetic predisposition, and the mediation of abnormal intestinal flora. The main objective of the current study is to further identify the risk factors for the development of IBD. Currently, there is very little knowledge about circadian rhythm and IBD and there are only a few studies on the relationship between sleep disturbances and the course of the disease, as well as pro- and anti-inflammatory cytokine profile and general immune system functioning. Furthermore, the relationship between the expression of circadian rhythm genes and severe course of IBD is still unknown. The aim of this review is to show the current state of knowledge about the relationship between circadian rhythm disorders, sleep disturbance and inflammation in the GI tract and to analyze the possibility of employing this knowledge in diagnosis and treatment of IBD.

Concomitant Thyroid Disorders and Inflammatory Bowel Disease: A Literature Review

The aim of this report was to review and summarize the literature on cases of concomitant inflammatory bowel disease (IBD) and thyroid diseases. We included the following previous case reports of concomitant IBD and thyroid diseases: 16 cases of ulcerative colitis (UC) and Graves' disease (GD), 3 cases of Crohn's disease (CD) and GD, 10 cases of CD and Hashimoto's thyroiditis (HT), 4 cases of IBD and subacute thyroiditis (SAT) or SAT-like symptoms, and 13 cases of IBD (12/13 cases were CD) and amyloid goiter. There might be no obvious differences of prevalence of thyroid dysfunction (hyper- or hypothyroidism), GD, and thyroid cancer between IBD patients and general populations. However, concomitant UC and HT might be relatively common in patients with multiple autoimmune disorders, and AG is one of the complications with CD patients. There might be no obvious differences of fatal prognoses between IBD patients with thyroid diseases and patients with thyroid diseases without IBD.

Comparative activities of milk components in reversing chronic colitis

Inflammatory bowel disease (IBD) is a poorly understood chronic immune disorder for which there is no medical cure. Milk and colostrum are rich sources of bioactives with immunomodulatory properties. Here we compared the therapeutic effects of oral delivery of bovine milk-derived iron-saturated lactoferrin (Fe-bLF), angiogenin, osteopontin (OPN), colostrum whey protein, Modulen IBD (Nestle Healthsciences, Rhodes, Australia), and cis-9,trans-11 conjugated linoleic acid (CLA)-enriched milk fat in a mouse model of dextran sulfate-induced colitis. The CLA-enriched milk fat significantly increased mouse body weights after 24d of treatment, reduced epithelium damage, and downregulated the expression of proinflammatory cytokines and nitrous oxide. Modulen IBD most effectively decreased the clinical score at d 12, and Modulen IBD and OPN most effectively lowered the inflammatory score. Myeloperoxidase activity that denotes neutrophil infiltration was significantly lower in mice fed Modulen IBD, OPN, angiogenin, and Fe-bLF. A significant decrease in the numbers of T cells, natural killer cells, dendritic cells, and a significant decrease in cytokine expression were observed in mice fed the treatment diets compared with dextran sulfate administered mice. The Fe-bLF, CLA-enriched milk fat, and Modulen IBD inhibited intestinal angiogenesis. In summary, each of the milk components attenuated IBD in mice, but with differing effectiveness against specific disease parameters.

Calculated Parameters of Thyroid Homeostasis: Emerging Tools for Differential Diagnosis and Clinical Research

Although technical problems of thyroid testing have largely been resolved by modern assay technology, biological variation remains a challenge. This applies to subclinical thyroid disease, non-thyroidal illness syndrome, and those 10% of hypothyroid patients, who report impaired quality of life, despite normal thyrotropin (TSH) concentrations under levothyroxine (L-T4) replacement. Among multiple explanations for this condition, inadequate treatment dosage and monotherapy with L-T4 in subjects with impaired deiodination have received major attention. Translation to clinical practice is difficult, however, since univariate reference ranges for TSH and thyroid hormones fail to deliver robust decision algorithms for therapeutic interventions in patients with more subtle thyroid dysfunctions. Advances in mathematical and simulative modeling of pituitary-thyroid feedback control have improved our understanding of physiological mechanisms governing the homeostatic behavior. From multiple cybernetic models developed since 1956, four examples have also been translated to applications in medical decision-making and clinical trials. Structure parameters representing fundamental properties of the processing structure include the calculated secretory capacity of the thyroid gland (SPINA-GT), sum activity of peripheral deiodinases (SPINA-GD) and Jostel's TSH index for assessment of thyrotropic pituitary function, supplemented by a recently published algorithm for reconstructing the personal set point of thyroid homeostasis. In addition, a family of integrated models (University of California-Los Angeles platform) provides advanced methods for bioequivalence studies. This perspective article delivers an overview of current clinical research on the basis of mathematical thyroid models. In addition to a summary of large clinical trials, it provides previously unpublished results of validation studies based on simulation and clinical samples.

Exploring the role and diversity of mucins in health and disease with special insight into non-communicable diseases

Mucins are major glycoprotein components of the mucus that coats the surfaces of cells lining the respiratory, digestive, gastrointestinal and urogenital tracts. They function to protect epithelial cells from infection, dehydration and physical or chemical injury, as well as to aid the passage of materials through a tract i.e., lubrication. They are also implicated in the pathogenesis of benign and malignant diseases of secretory epithelial cells. In Human there are two types of mucins, membrane-bound and secreted that are originated from mucous producing goblet cells localized in the epithelial cell layer or in mucous producing glands and encoded by MUC gene. Mucins belong to a heterogeneous family of high molecular weight proteins composed of a long peptidic chain with a large number of tandem repeats that form the so-called mucin domain. The molecular weight is generally high, ranging between 0.2 and 10 million Dalton and all mucins contain one or more domains which are highly glycosylated. The size and number of repeats vary between mucins and the genetic polymorphism represents number of repeats (VNTR polymorphisms), which means the size of individual mucins can differ substantially between individuals which can be used as markers. In human it is only MUC1 and MUC7 that have mucin domains with less than 40% serine and threonine which in turn could reduce number of PTS domains. Mucins can be considered as powerful two-edged sword, as its normal function protects from unwanted substances and organisms at an arm's length while, malfunction of mucus may be an important factor in human diseases. In this review we have unearthed the current status of different mucin proteins in understanding its role and function in various non-communicable diseases in human with special reference to its organ specific locations. The findings described in this review may be of direct relevance to the major research area in biomedicine with reference to mucin and mucin associated diseases.

Nonthyroidal Illness Syndrome in Cardiac Illness Involves Elevated Concentrations of 3,5-Diiodothyronine and Correlates with Atrial Remodeling

BACKGROUND

Although hyperthyroidism predisposes to atrial fibrillation, previous trials have suggested decreased triiodothyronine (T3) concentrations to be associated with postoperative atrial fibrillation (POAF). Therapy with thyroid hormones (TH), however, did not reduce the risk of POAF. This study reevaluates the relation between thyroid hormone status, atrial electromechanical function and POAF.

METHODS

Thirty-nine patients with sinus rhythm and no history of atrial fibrillation or thyroid disease undergoing cardiac surgery were prospectively enrolled. Serum concentrations of thyrotropin, free (F) and total (T) thyroxine (T4) and T3, reverse (r)T3, 3-iodothyronamine (3-T1AM) and 3,5-diiodothyronine (3,5-T2) were measured preoperatively, complemented by evaluation of echocardiographic and electrophysiological parameters of cardiac function. Holter-ECG and telemetry were used to screen for POAF for 10 days following cardiac surgery.

RESULTS

Seven of 17 patients who developed POAF demonstrated nonthyroidal illness syndrome (NTIS; defined as low T3 and/or low T4 syndrome), compared to 2 of 22 (p < 0.05) patients who maintained sinus rhythm. In patients with POAF, serum FT3 concentrations were significantly decreased, but still within their reference ranges. 3,5-T2 concentrations directly correlated with rT3 concentrations and inversely correlated with FT3 concentrations. Furthermore, 3,5-T2 concentrations were significantly elevated in patients with NTIS and in subjects who eventually developed POAF. In multivariable logistic regression FT3, 3,5-T2, total atrial conduction time, left atrial volume index and Fas ligand were independent predictors of POAF.

CONCLUSION

This study confirms reduced FT3 concentrations in patients with POAF and is the first to report on elevated 3,5-T2 concentrations in cardiac NTIS. The pathogenesis of NTIS therefore seems to involve more differentiated allostatic mechanisms.

TSH and Thyrotropic Agonists: Key Actors in Thyroid Homeostasis

This paper provides the reader with an overview of our current knowledge of hypothalamic-pituitary-thyroid feedback from a cybernetic standpoint. Over the past decades we have gained a plethora of information from biochemical, clinical, and epidemiological investigation, especially on the role of TSH and other thyrotropic agonists as critical components of this complex relationship. Integrating these data into a systems perspective delivers new insights into static and dynamic behaviour of thyroid homeostasis. Explicit usage of this information with mathematical methods promises to deliver a better understanding of thyrotropic feedback control and new options for personalised diagnosis of thyroid dysfunction and targeted therapy, also by permitting a new perspective on the conundrum of the TSH reference range.