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Fibrinolysis protease receptors promote activation of astrocytes to express pro-inflammatory cytokines.
BACKGROUND:Astrocytes contribute to the crosstalk that generates chronic neuro-inflammation in neurological diseases; however, compared with microglia, astrocytes respond to a more limited continuum of innate immune system stimulants. Recent studies suggest that the fibrinolysis system may regulate inflammation. The goal of this study was to test whether fibrinolysis system components activate astrocytes and if so, elucidate the responsible biochemical pathway. METHODS:Primary cultures of astrocytes and microglia were prepared from neonatal mouse brains. The ability of purified fibrinolysis system proteins to elicit a pro-inflammatory response was determined by measuring expression of the mRNAs encoding tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and chemokine (C-C motif) ligand 2 (CCL2). IκBα phosphorylation also was measured. Plasminogen activation in association with cells was detected by chromogenic substrate hydrolysis. The activity of specific receptors was tested using neutralizing antibodies and reagents. RESULTS:Astrocytes expressed pro-inflammatory cytokines when treated with plasminogen but not when treated with agonists for Toll-like Receptor-4 (TLR4), TLR2, or TLR9. Microglia also expressed pro-inflammatory cytokines in response to plasminogen; however, in these cells, the response was observed only when tissue-type plasminogen activator (tPA) was added to activate plasminogen. In astrocytes, endogenously produced urokinase-type plasminogen activator (uPA) converted plasminogen into plasmin in the absence of tPA. Plasminogen activation was dependent on the plasminogen receptor, α-enolase, and the uPA receptor, uPAR. Although uPAR is capable of directly activating cell-signaling, the receptor responsible for cytokine expression and IκBα phosphorylation response to plasmin was Protease-activated Receptor-1 (PAR-1). The pathway, by which plasminogen induced astrocyte activation, was blocked by inhibiting any one of the three receptors implicated in this pathway with reagents such as εACA, α-enolase-specific antibody, uPAR-specific antibody, the uPA amino terminal fragment, or a pharmacologic PAR-1 inhibitor. CONCLUSIONS:Plasminogen may activate astrocytes for pro-inflammatory cytokine expression through the concerted action of at least three distinct fibrinolysis protease receptors. The pathway is dependent on uPA to activate plasminogen, which is expressed endogenously by astrocytes in culture but also may be provided by other cells in the astrocytic cell microenvironment in the CNS
Thyroid ultrasonography reporting: consensus of Italian Thyroid Association (AIT), Italian Society of Endocrinology (SIE), Italian Society of Ultrasonography in Medicine and Biology (SIUMB) and Ultrasound Chapter of Italian Society of Medical Radiology (SIRM)
Thyroid ultrasonography (US) is the gold standard for thyroid imaging and its widespread use is due to an optimal spatial resolution for superficial anatomic structures, a low cost and the lack of health risks. Thyroid US is a pivotal tool for the diagnosis and follow-up of autoimmune thyroid diseases, for assessing nodule size and echostructure and defining the risk of malignancy in thyroid nodules. The main limitation of US is the poor reproducibility, due to the variable experience of the operators and the different performance and settings of the equipments. Aim of this consensus statement is to standardize the report of thyroid US through the definition of common minimum requirements and a correct terminology. US patterns of autoimmune thyroid diseases are defined. US signs of malignancy in thyroid nodules are classified and scored in each nodule. We also propose a simplified nodule risk stratification, based on the predictive value of each US sign, classified and scored according to the strength of association with malignancy, but also to the estimated reproducibility among different operators
Vitamin D deficiency: A new risk factor for type 2 diabetes?
Recent compelling evidence suggests a role of vitamin D deficiency in the pathogenesis of insulin resistance and insulin secretion derangements, with a consequent possible interference with type 2 diabetes mellitus. The mechanism of this link is incompletely understood. In fact, vitamin D deficiency is usually detected in obesity in which insulin resistance is also a common finding. The coexistence of insulin resistance and vitamin D deficiency has generated several hypotheses. Some cross-sectional and prospective studies have suggested that vitamin D deficiency may play a role in worsening insulin resistance; others have identified obesity as a risk factor predisposing individuals to exhibit both vitamin D deficiency and insulin resistance. The available data from intervention studies are largely confounded, and inadequate considerations of seasonal effects on 25(OH)D concentrations are also a common design flaw in many studies. On the contrary, there is strong evidence that obesity might cause both vitamin D deficiency and insulin resistance, leaving open the possibility that vitamin D and diabetes are not related at all. Although it might seem premature to draw firm conclusions on the role of vitamin D supplementation in reducing insulin resistance and preventing type 2 diabetes, this manuscript will review the circumstances leading to vitamin D deficiency and how such a deficiency can eventually independently affect insulin sensitivity. © 2012 S. Karger AG, Basel
25-hydroxyvitamin D concentration correlates with insulin-sensitivity and BMI in obesity
The prevalence of hypovitaminosis D is high among obese subjects. Further, low 25-hydroxyvitamin D (25(OH)D) concentration has been postulated to be a risk factor for type 2 diabetes, although its relation with insulin-sensitivity is not well investigated. Thus, we aimed to investigate the relationship between 25(OH)D concentration and insulin-sensitivity, using the glucose clamp technique. In total, 39 subjects with no known history of diabetes mellitus were recruited. The association of 25(OH)D concentration with insulin-sensitivity was evaluated by hyperinsulinemic euglycemic clamp. Subjects with low 25(OH)D (<50nmol/l) had higher BMI (P = 0.048), parathyroid hormone (PTH) (P = 0.040), total cholesterol (P = 0.012), low-density lipoprotein (LDL) cholesterol (P = 0.044), triglycerides (P = 0.048), and lower insulin-sensitivity as evaluated by clamp study (P = 0.047). There was significant correlation between 25(OH)D and BMI (r = -0.58; P = 0.01), PTH (r = -0.44; P 0.01), insulin-sensitivity (r = -0.43; P < 0.01), total (r = -0.34; P = 0.030) and LDL (r = -0.40; P = 0.023) (but not high-density lipoprotein (HDL)) cholesterol, and triglycerides (r = -0.45; P = 0.01). Multivariate analysis using 25(OH)D concentration, BMI, insulin-sensitivity, HDL cholesterol, LDL cholesterol, total cholesterol, and triglycerides, as the cofactors was performed. BMI was found to be the most powerful predictor of 25(OH)D concentration (r = -0.52; P < 0.01), whereas insulin-sensitivity was not significant. Our study suggested that there is no cause-effect relationship between vitamin D and insulin-sensitivity. In obesity, both low 25(OH)D concentration and insulin-resistance appear to be dependent on the increased body size. © 2010 The Obesity Society
Sotagliflozin, the first dual SGLT inhibitor. Current outlook and perspectives
Sotagliflozin is a dual sodium-glucose co-transporter-2 and 1 (SGLT2/1) inhibitor for the treatment of both type 1 (T1D) and type 2 diabetes (T2D). Sotagliflozin inhibits renal sodium-glucose co-transporter 2 (determining significant excretion of glucose in the urine, in the same way as other, already available SGLT-2 selective inhibitors) and intestinal SGLT-1, delaying glucose absorption and therefore reducing post prandial glucose. Well-designed clinical trials, have shown that sotagliflozin (as monotherapy or add-on therapy to other anti-hyperglycemic agents) improves glycated hemoglobin in adults with T2D, with beneficial effects on bodyweight and blood pressure. Similar results have been obtained in adults with T1D treated with either continuous subcutaneous insulin infusion or multiple daily insulin injections, even after insulin optimization. A still ongoing phase 3 study is currently evaluating the effect of sotagliflozin on cardiovascular outcomes (ClinicalTrials.gov NCT03315143). In this review we illustrate the advantages and disadvantages of dual SGLT 2/1 inhibition, in order to better characterize and investigate its mechanisms of action and potentialities
Analysis of adenomatous polyposis coli gene in thyroid tumours.
Familial adenomatous polyposis (FAP) is known to be associated with neoplasia of various tissues, including thyroid carcinoma. Germline mutations of the tumour-suppressor gene APC, responsible for the predisposition to FAP, may therefore be involved in the pathogenesis of these tumours. In this report the structure of the APC gene has been investigated in 26 thyroid tumours, at different stages of dedifferentiation, that were surgically excised from patients with a negative history of FAP. Approximately 35% of the APC gene coding region, where most of the mutations are clustered, has been analysed by a combination of single-strand conformation polymorphism and direct sequencing. No significant alterations could be demonstrated in any sample examined. It is concluded that, at least in patients not affected by FAP, APC gene abnormalities do not seem to play a relevant role in the pathogenesis of thyroid carcinoma
PARP inhibitors affect growth, survival and radiation susceptibility of human alveolar and embryonal rhabdomyosarcoma cell lines
PARP inhibitors (PARPi) are used in a wide range of human solid tumours but a limited evidence is reported in rhabdomyosarcoma (RMS), the most frequent childhood soft-tissue sarcoma. The cellular and molecular effects of Olaparib, a specific PARP1/2 inhibitor, and AZD2461, a newly synthesized PARP1/2/3 inhibitor, were assessed in alveolar and embryonal RMS cells both as single-agent and in combination with ionizing radiation (IR)
Single-fiber conduction velocity test allows earlier detection of abnormalities in diabetes
Introduction: The purpose of this study was to determine whether single-fiber conduction velocity (SF-CV) of a small number of axons increases sensitivity for identification of motor nerve conduction alterations in patients with diabetes. Methods: Twenty-one consecutive diabetic patients in good metabolic control were studied. For each patient, conventional (C-CV) and SF-CV results were correlated with the presence of neuropathic symptoms. Results: Nine of 21 patients reported symptoms suggestive of mild nerve impairment. Three patients had abnormal sural nerve CV, 1 of whom also had abnormal motor nerve conduction. Eighteen patients had normal findings on conventional tests, 3 of whom had slowing of SF-CV. Conclusions: SF-CV is able to detect mild myelin damage with higher sensitivity than conventional tests. The use of SF-CV may be a helpful tool in the early identification of diabetic polyneuropathy, and it may be useful for tailoring an approach to diabetic polyneuropathy. © 2010 Wiley Periodicals, Inc
Adrenocortical incidentalomas and bone: from molecular insights to clinical perspectives
Adrenal incidentalomas constitute a common clinical problem with an overall prevalence of around 2–3%, but are more common with advancing age being present in 10% of those aged 70 years. The majority of these lesions are benign adrenocortical adenomas (80%), characterized in 10–40% of the cases by autonomous cortisol hypersecretion, and in 1–10% by aldosterone hypersecretion. Several observational studies have shown that autonomous cortisol and aldosterone hypersecretion are more prevalent than expected in patients with osteopenia and osteoporosis: these patients have accelerated bone loss and an increased incidence of vertebral fractures. In contrast to glucocorticoid action, the effects of aldosterone on bone are less well understood. Recent data, demonstrating a concomitant co-secretion of glucocorticoid metabolites in patients with primary aldosteronism, could explain some of the metabolic abnormalities seen in patients with aldosterone hypersecretion. In clinical practice, patients with unexplained osteoporosis, particularly when associated with other features such as impaired glucose tolerance or hypertension, should be investigated for the possible presence of autonomous cortisol or aldosterone secretion due to an adrenal adenoma. Randomized intervention studies are needed, however, to investigate the optimum interventions for osteoporosis and other co-morbidities in these patients
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