Thyroid hormones and antioxidant systems: focus on oxidative stress in cardiovascular and pulmonary diseases.

In previous works we demonstrated an inverse correlation between plasma Coenzyme Q10 (CoQ10) and thyroid hormones; in fact, CoQ10 levels in hyperthyroid patients were found among the lowest detected in human diseases. On the contrary, CoQ10 is elevated in hypothyroid subjects, also in subclinical conditions, suggesting the usefulness of this index in assessing metabolic status in thyroid disorders. A Low-T3 syndrome is a condition observed in several chronic diseases: it is considered an adaptation mechanism, where there is a reduction in pro-hormone T4 conversion. Low T3-Syndrome is not usually considered to be corrected with replacement therapy. We review the role of thyroid hormones in regulation of antioxidant systems, also presenting data on total antioxidant capacity and Coenzyme Q10. Published studies suggest that oxidative stress could be involved in the clinical course of different heart diseases; our data could support the rationale of replacement therapy in low-T3 conditions.

Molecular diagnosis of polycystic ovary syndrome in obese and non-obese women by targeted plasma miRNA profiling.

OBJECTIVE: Polycystic ovary syndrome (PCOS) is diagnosed based on the clinical signs, but its presentation is heterogeneous and potentially confounded by concurrent conditions, such as obesity and insulin resistance. miRNA have recently emerged as putative pathophysiological and diagnostic factors in PCOS. However, no reliable miRNA-based method for molecular diagnosis of PCOS has been reported. The aim of this study was to develop a tool for accurate diagnosis of PCOS by targeted miRNA profiling of plasma samples, defined on the basis of unbiased biomarker-finding analyses and biostatistical tools. METHODS: A case-control PCOS cohort was cross-sectionally studied, including 170 women classified into four groups: non-PCOS/lean, non-PCOS/obese, PCOS/lean, and PCOS/obese women. High-throughput miRNA analyses were performed in plasma, using NanoString technology and a 800 human miRNA panel, followed by targeted quantitative real-timePCR validation. Statistics were applied to define optimal normalization methods, identify deregulated biomarker miRNAs, and build classification algorithms, considering PCOS and obesity as major categories. RESULTS: The geometric mean of circulating hsa-miR-103a-3p, hsa-miR-125a-5p, and hsa-miR-1976, selected among 125 unchanged miRNAs, was defined as optimal reference for internal normalization (named mR3-method). Ten miRNAs were identified and validated after mR3-normalization as differentially expressed across the groups. Multinomial least absolute shrinkage and selection operator regression and decision-tree models were built to reliably discriminate PCOS vs non-PCOS, either in obese or non-obese women, using subsets of these miRNAs as performers. CONCLUSIONS: We define herein a robust method for molecular classification of PCOS based on unbiased identification of miRNA biomarkers and decision-tree protocols. This method allows not only reliable diagnosis of non-obese women with PCOS but also discrimination between PCOS and obesity. CAPSULE: We define a novel protocol, based on plasma miRNA profiling, for molecular diagnosis of PCOS. This tool not only allows proper discrimination of the condition in non-obese women but also permits distinction between PCOS and obesity, which often display overlapping clinical presentations.

Persistent Reduction of Circulating Myeloid Calcifying Cells in Acromegaly: Relevance to the Bone-Vascular Axis.

Context: Acromegaly is a systemic disease characterized by persistent bone pathology and excess cardiovascular mortality. Despite multiple concomitant risk factors, atherosclerosis does not seem to be accelerated in acromegaly. Objective: To compare the levels of circulating myeloid calcifying cells (MCCs), which promote ectopic calcification and inhibit angiogenesis, in individuals with and without acromegaly. Design: Cross-sectional case-control study. Setting: Tertiary ambulatory referral endocrinology center. Patients: 44 acromegalic patients (25 active; 19 inactive), 44 control subjects matched by age, sex, risk factors, and medications, and 8 patients cured of acromegaly. Intervention: MCCs were measured using flow cytometry based on the expression of osteocalcin (OC) and bone alkaline phosphatase (BAP) on monocytes and circulating CD34+ stem cells. Main Outcome Measure: Differences in MCCs between patients and controls. Results: OC+BAP+ MCCs were severely reduced in acromegalic compared with control patients (0.17% ± 0.02% vs 1.00% ± 0.24%; P < 0.001), as were the total OC+ and BAP+ monocytic cells. Patients with inactive acromegaly and those cured of acromegaly displayed persistently reduced levels of MCCs. In the controls, but not acromegalic patients, MCCs were increased in the presence of diabetes or cardiovascular disease. A direct correlation was noted between MCCs and parathyroid hormone (r = 0.61; P < 0.0001), supporting a link between bone biology and MCCs. Conclusions: In patients with acromegaly, the levels of MCCs are reduced and remain low, even years after a complete cure. This finding might be related to low atherosclerotic calcification and the persistence of bone pathology after acromegaly remission or cure.

NETosis is induced by high glucose and associated with type 2 diabetes.

AIMS: The role of neutrophils in diabetes and its complications is unclear. Upon challenge with microbes and inflammatory triggers, neutrophils release enzymes and nuclear material, forming neutrophils extracellular traps (NETs) and thereby dying by NETosis. We herein tested NET formation and NETosis products in high glucose and in the setting of type 2 diabetes (T2D). METHODS: NETosis was assessed in vitro in cells exposed to 0, 5, 25 mM glucose and 25 mM mannitol, DMSO and PMA using immunofluorescence staining for elastase, DNA and chromatin. Single-cell morphometric analysis was used to detect enter of elastase in the nucleus and extrusion of nuclear material. Release of NETs was quantified by staining with Hoechst 33342. In 38 T2D and 38 age- and sex-matched non-diabetic individuals, we determined plasma elastase, mono- and oligonucleosomes and double-strand (ds) DNA, as circulating NETosis products. RESULTS: NETosis was accurately reproduced in vitro: high (25 mM) glucose increased NETosis rate and release of NETs compared with 5 mM glucose and 25 mM mannitol. T2D patients showed increased plasma elastase, mono- and oligonucleosomes and dsDNA compared with non-diabetic control individuals. A positive correlation was found between HbA1c and mono- and oligonucleosomes, whereas dsDNA was correlated with the presence of nephropathy and cardiovascular disease. Serum IL-6 concentrations were higher in T2D compared with CTRL and correlated with serum dsDNA levels. CONCLUSIONS: High glucose and hyperglycemia increase release of NETs and circulating markers of NETosis, respectively. This finding provides a link among neutrophils, inflammation and tissue damage in diabetes.