Myo-inositol in autoimmune thyroiditis, and hypothyroidism

Autoimmunity, New Potential Biomarkers and the Thyroid Gland-The Perspective of Hashimoto's Thyroiditis and Its Treatment

Autoimmune thyroid disease (AITD) is the most common organic specific illness of the thyroid gland. It may manifest as the overproduction or the decline of thyroxine and triiodothyronine. Hyperthyroidism develops due to the overproduction of hormones as an answer to the presence of stimulatory antibodies against the TSH receptor. Hashimoto's thyroiditis (HT) is generally characterized by the presence of thyroid peroxidase and thyroglobulin antibodies, with a concomitant infiltration of lymphocytes in the thyroid. Due to the progressive destruction of cells, AITD can lead to subclinical or overt hypothyroidism. Pathophysiology of AITD is extremely complicated and still not fully understood, with genetic, environmental and epigenetic factors involved in its development. Due to increasing incidence and social awareness of this pathology, there is an urgent need to expand the background concerning AITD. A growing body of evidence suggests possible ways of treatment apart from traditional approaches. Simultaneously, the role of potential new biomarkers in the diagnosis and monitoring of AITD has been highlighted recently, too. Therefore, we decided to review therapeutic trends in the course of AITD based on its pathophysiological mechanisms, mainly focusing on HT. Another aim was to summarize the state of knowledge regarding the role of new biomarkers in this condition.

Metabolite signature of human malignant thyroid tissue: A systematic review and meta-analysis

BACKGROUND

Thyroid cancer (TC) is the predominant malignancy within the endocrine system. However, the standard method for TC diagnosis lacks the capability to identify the pathological condition of all thyroid lesions. The metabolomics approach has the potential to manage this problem by identifying differential metabolites.

AIMS

This study conducted a systematic review and meta-analysis of the NMR-based metabolomics studies in order to identify significant altered metabolites associated with TC.

METHODS

A systematic search of published literature in any language in three databases including Embase, PubMed, and Scopus was conducted. Out of 353 primary articles, 12 studies met the criteria for inclusion in the systematic review. Among these, five reports belonging to three articles were eligible for meta-analysis. The correlation coefficient of the orthogonal partial least squares discriminant analysis, a popular model in the multivariate statistical analysis of metabolomic data, was chosen for meta-analysis. The altered metabolites were chosen based on the fact that they had been found in at least three studies.

RESULTS

In total, 49 compounds were identified, 40 of which were metabolites. The increased metabolites in thyroid lesions compared normal samples included lactate, taurine, alanine, glutamic acid, glutamine, leucine, lysine, phenylalanine, serine, tyrosine, valine, choline, glycine, and isoleucine. Lipids were the decreased compounds in thyroid lesions. Lactate and alanine were increased in malignant versus benign thyroid lesions, while, myo-inositol, scyllo-inositol, citrate, choline, and phosphocholine were found to be decreased. The meta-analysis yielded significant results for three metabolites of lactate, alanine, and citrate in malignant versus benign specimens.

DISCUSSION

In this study, we provided a concise summary of 12 included metabolomic studies, making it easier for future researchers to compare their results with the prior findings.

CONCLUSION

It appears that the field of TC metabolomics will experience notable advancement, leading to the discovery of trustworthy diagnostic and prognostic biomarkers.

Chemokines in thyroid autoimmunity

The chemokine receptor CXCR3 and its chemokines CXCL9, CXCL10, and CXCL11 are involved in the pathogenesis of autoimmune diseases. Th1 lymphocytes are recruited by Th1 chemokines, secreted by damaged cells. In inflamed tissues, the attracted Th1 lymphocytes induce the IFN-gamma and TNF-alpha release, that stimulates the secretion of Th1 chemokines, initiating and reiterating an amplification feedback loop. Autoimmune thyroid disorders (AITD) are the most recurrent autoimmune diseases, including Graves' disease (GD) and autoimmune thyroiditis, clinically defined by thyrotoxicosis and hypothyroidism, respectively. Graves' ophthalmopathy is one of GD extrathyroidal manifestations, occurring in ~30-50% of GD patients. In the early phase of AITD, the Th1 immune response is prevalent, and a following switch to a Th2 immune response has been shown in the late, inactive, phase. The reviewed data underline the importance of chemokines in thyroid autoimmunity and suggest CXCR3-receptor and its chemokines as potential targets of novel drugs for these disorders.

The impact of vitamin D on thyroid autoimmunity and hypothalamic-pituitary-thyroid axis activity in myo-inositol-treated and myo-inositol-naïve women with autoimmune thyroiditis: A pilot study

WHAT IS KNOWN AND OBJECTIVE

Vitamin D and myo-inositol reduce thyroid antibody titers in subjects with autoimmune thyroiditis. No previous study has investigated interactions between these agents. The aim of the current study was to determine whether the impact of exogenous vitamin D on thyroid autoimmunity and thyroid function in women with Hashimoto's thyroiditis depends on myo-inositol supplementation.

METHODS

The study population consisted of three thyroid antibody- and insulin sensitivity-matched groups of women with autoimmune thyroiditis and high-normal or slightly elevated TSH levels. Forty-one women (21 in group A and 20 in group C) had been treated for at least 6 months with myo-inositol (group A), while 21 women (group B) had not received myo-inositol preparations. Over the entire study period (6 months), groups A and C continued treatment with myo-inositol (2 g daily), while groups A and B received exogenous vitamin D (4000 IU daily). Plasma titers of thyroid peroxidase and thyroglobulin antibodies, as well as plasma concentrations of glucose, insulin, TSH, free thyroid hormones, prolactin, and 25-hydroxyvitamin D (25-OH-D) were assessed at entry and 6 months later. Moreover, baseline and follow-up values of the structure parameters of thyroid homeostasis were calculated RESULTS AND DISCUSSION: In groups A and B, vitamin D improved insulin sensitivity and increased 25-OH-D levels. Although follow-up antibody titers in both these groups were lower than baseline ones, the impact of vitamin D on thyroid peroxidase and thyroglobulin antibodies was stronger in group A than in group B. Only in group A, vitamin D decreased TSH levels and increased SPINA-GT. There were no differences between baseline and follow-up free values of glucose, thyroid hormones, prolactin, Jostel's index, and SPINA-GD. The impact of vitamin D treatment on antibody titers correlated with treatment-induced changes in 25-OH-D levels and the degree of improvement in insulin sensitivity. In group C, glucose homeostasis markers, antibody titers and hormone levels remained at a similar level throughout the study period.

WHAT IS NEW AND CONCLUSION

The obtained results suggest that the impact of vitamin D on thyroid autoimmunity and hypothalamic-pituitary-thyroid axis activity in subjects with autoimmune thyroiditis is more pronounced if they receive myo-inositol.

Redefining the Cut-Off Ranges for TSH Based on the Clinical Picture, Results of Neuroimaging and Laboratory Tests in Unsupervised Cluster Analysis as Individualized Diagnosis of Early Schizophrenia

Thyroid abnormalities, including mild forms of hypothyroidism and hyperthyroidism, are reported as risk factors for the development of a number of neuropsychiatric disorders, including schizophrenia. The diagnostic process still takes into account the extreme ranges of the accepted reference values for serum TSH since the concentration of free thyroxine in the serum does not change by definition. TSH mU/L cut-off values in psychiatric patients are currently clinically considered in the case of extremely high serum TSH levels (>4.0 mU/L). The results obtained in this study suggest that the clinically significant value has a lower TSH cut-off point with an upper limit of 2–2.5 mU/L. The criteria for the differential diagnosis of patients with schizophrenia, however, mainly take into account statutory reference ranges without a background related to the history of thyroid diseases in the family. The results indicate the need to lower the upper cut-off values for TSH among patients with early psychosis, which is related to the potential clinical significance of the obtained values both in the field of clinical evaluation and neuroimaging and laboratory evaluation parameters. The cut-off points obtained with the prior available knowledge coincided with the values established in the unsupervised clustering method, which further confirms the legitimacy of their use in the individualized diagnosis strategy of schizophrenia.

Myoinositol in Autoimmune Thyroiditis

Myoinositol (Myo) is an isoform of inositol, a cyclic polyol with 6 hydroxyl groups. Myo is mainly derived from dietary intake while its endogenous production is generated from glucose by enzymatic reactions. Moreover, Myo is also synthesized de novo by catabolism of phosphatidylinositol (PI), phosphoinositides (PIP), and inositol phosphates (IP). Myo has a determinant role in thyroid function and autoimmune diseases as it regulates iodine organification and thyroid hormone biosynthesis by the formation of hydrogen peroxide (H₂O₂) in thyrocytes. Depletion of Myo that is involved in the thyroid stimulating hormone (TSH) signaling pathway, may cause the development of thyroid diseases such as hypothyroidism. TSH levels significantly decreased in patients with subclinical hypothyroidism, with or without autoimmune thyroiditis, after treatment with Myo plus Selenium (Myo+Se). In addition to TSH, antithyroid autoantibodies are reduced. This review summarizes the role of Myo in the thyroidal physiology and its role in the management of some thyroid diseases.

Supplementation with myo-inositol and Selenium improves the clinical conditions and biochemical features of women with or at risk for subclinical hypothyroidism

PURPOSE

The present study aims to evaluate the effect of myo-Inositol plus Selenium supplementation in patients affected by subclinical hypothyroidism.

METHODS

One hundred and forty-eight patients were included in the study from 8 different centers of Slovakia, and treated for 6 months with a daily dose of 600 mg myo-Ins plus 83 mcg Se. The patients included at the enrollment were women of reproductive age (18-50), who exhibit values of TSH in the range 2.5-5 mU/l and positivity to antibodies TPO-Ab/TG-Ab, or otherwise values of TSH in the range 5-10 mU/l both with and without positivity to antibodies TPO-Ab/TG-Ab.

RESULTS

Patients affected by subclinical hypothyroidism exhibited a significant improvement of their condition when treated for 6 months with a combination of myo-Inositol and Selenium. The TSH values significantly ameliorated along with the index of autoimmunity and the thyroid status. In a sub-class of patients, the auto-antibody titer decreased after myo-inositol + Selenium administration. The treatment also induces a regularization of the menstrual cycle and a reduction of the cholesterol in the patients enrolled for the study. Furthermore, a significant improvement is observed in the perception of the symptoms associated with subclinical hypothyroidism over the treatment period.

CONCLUSION

A dietary supplementation with of myo-Inositol and Selenium in the treatment of patients affected by subclinical hypothyroidism exhibits a beneficial role in the recovery of TSH values, in the improvement of the symptoms associated to this condition and in the maintenance of the thyroid functions.The trial was approved by the Ethical Committee from National Institute of Endocrinology and Diabetology of Lubochna, Slovakia, date 18.12.2018, registration number: 3124/2018.

Precision Medicine in Autoimmune Thyroiditis and Hypothyroidism

Autoimmune thyroid diseases (AITD) are T-cell-mediated organ specific autoimmune disorders, deriving from an altered response of the immune system that leads to the immune attack to the thyroid. Hashimoto’s thyroiditis (HT) and Graves’ disease (GD) are the two principal AITD clinical presentations. Hypothyroidism and thyrotoxicosis are, respectively, the clinical hallmarks of HT and GD. Patients with autoimmune thyroiditis are treated daily with synthetic L-thyroxine (L-T4) at the dose of 1.5–1.7 μg/kg. Various L-T4 formulations are commercially available (tablet, liquid solution, or soft gel capsule). L-T4 in tablets is generally prescribed to treat hypothyroidism, whereas the liquid formulation, or soft gel capsules, can be administered in hypothyroid patients in case of malabsorption or in patients in therapy with drugs interfering with L-T4 absorption. Furthermore, myoinositol has a crucial role in thyroid autoimmunity and function. Clinical studies reported a significant decline in TSH and antithyroid autoantibodies levels after treatment with myoinositol + selenium in patients with subclinical hypothyroidism and autoimmune thyroiditis. Moreover, thyroidectomy can be rarely recommended in patients with autoimmune thyroiditis, with cosmetic reasons for a goiter, or with important signs or symptoms of local compression, or nodular disease with a “suspicious” cytology for malignancy. Furthermore, a recent randomized trial suggested that total thyroidectomy can improve quality of life and fatigue, while medical therapy did not. In this review, we overview currently available evidence in personalized medicine in patients with autoimmune thyroiditis and hypothyroidism. Further research is needed in larger population to investigate the effect of these new treatments on quality of life.

Metabolomics and cytokine profiling of mesenchymal stromal cells identify markers predictive of T-cell suppression

BACKGROUND AIMS

Mesenchymal stromal cells (MSCs) have shown great promise in the field of regenerative medicine, as many studies have shown that MSCs possess immunomodulatory function. Despite this promise, no MSC therapies have been licensed by the Food and Drug Administration. This lack of successful clinical translation is due in part to MSC heterogeneity and a lack of critical quality attributes. Although MSC indoleamine 2,3-dioxygnease (IDO) activity has been shown to correlate with MSC function, multiple predictive markers may be needed to better predict MSC function.

METHODS

Three MSC lines (two bone marrow-derived, one induced pluripotent stem cell-derived) were expanded to three passages. At the time of harvest for each passage, cell pellets were collected for nuclear magnetic resonance (NMR) and ultra-performance liquid chromatography mass spectrometry (MS), and media were collected for cytokine profiling. Harvested cells were also cryopreserved for assessing function using T-cell proliferation and IDO activity assays. Linear regression was performed on functional data against NMR, MS and cytokines to reduce the number of important features, and partial least squares regression (PLSR) was used to obtain predictive markers of T-cell suppression based on variable importance in projection scores.

RESULTS

Significant functional heterogeneity (in terms of T-cell suppression and IDO activity) was observed between the three MSC lines, as were donor-dependent differences based on passage. Omics characterization revealed distinct differences between cell lines using principal component analysis. Cell lines separated along principal component one based on tissue source (bone marrow-derived versus induced pluripotent stem cell-derived) for NMR, MS and cytokine profiles. PLSR modeling of important features predicted MSC functional capacity with NMR (R² = 0.86), MS (R² = 0.83), cytokines (R² = 0.70) and a combination of all features (R² = 0.88).

CONCLUSIONS

The work described here provides a platform for identifying markers for predicting MSC functional capacity using PLSR modeling that could be used as release criteria and guide future manufacturing strategies for MSCs and other cell therapies.

Differential lipids in pregnant women with subclinical hypothyroidism and their correlation to the pregnancy outcomes

Subclinical hypothyroidism (SCH) has become a prevalent complication in pregnancy. Recent research links SCH to disturbed thyroid lipid profile; however, it is unclear how lipid metabolism disorders contribute to the pathogenesis of SCH during pregnancy. Thus, we used nontargeted lipidomics to identify and compare the lipids and metabolites expressed by pregnant women with SCH and healthy pregnant women. Multivariate analysis revealed 143 lipid molecules differentially expressed between the SCH group and the control group. Based on fold change, 30 differentially expressed lipid metabolites are potential biomarkers. KEGG pathway enrichment analysis showed that the differentially expressed metabolites participate in several pathways, including response to pathogenic Escherichia coli infection, regulation of lipolysis in adipocytes, metabolic pathways, glycerophospholipid metabolism, and fat digestion and absorption pathways. Correlation analyses revealed sphingomyelin (SM) and phosphatidylcholine (PC) positively correlate to tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), and interleukin-6 (IL-6), while phosphatidylglycerol (PG), and phosphatidylinositol (PI) negatively correlate with them. In addition, PG positively correlates to birth weight. Thus, the lipid profile of pregnant women with SCH is significantly different from that of healthy pregnant women. Lipid molecules associated with the differential lipid metabolism, such as SM, phosphatidylethanolamine (PE), and PI, should be further investigated for their roles in the pathogenesis of SCH in pregnancy, as they might be targets for reducing the incidence of adverse pregnancy outcomes.

Analysis of metabolomics profile in hypothyroid patients before and after thyroid hormone replacement

PURPOSE

The serum metabolic changes occurring during the transition from hypothyroidism to euthyroidism are not known. This study aimed to determine the metabolomic profile in hypothyroid patients before (HypoT₀) and after (HypoT₁) euthyroidism achieved through levothyroxine (L-T4) treatment.

METHODS

Eighteen patients with overt primary hypothyroidism were recruited for the study. All patients were treated with L-T4 to achieve euthyroidism. Thyrotropin (TSH), free thyroxine (FT4), free triiodothyronine (FT3) and metabolomics profiles were measured before and after 3 months of treatment. The euthyroid control group consisted of 28 healthy volunteers. Metabolomics analysis was performed using Nuclear Magnetic Resonance (NMR) spectroscopy.

RESULTS

¹H NMR-based metabolomics profiling of patients with newly diagnosed hypothyroidism (HypoT₀) showed significantly higher levels of citrate, creatinine, glycerol, myo-inositol and serine, and lower levels of proline and taurine compared to controls. Interestingly, some metabolic changes were persistent three months after pharmacological treatments, despite normal serum TSH and thyroid hormone concentrations (HypoT₁). When an Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA) model was built to evaluate possible differences in the metabolic profile between HypoT₀ and HypoT₁, the data obtained were not significantly different.

CONCLUSION

These results suggest that metabolic changes in the patients with hypothyroidism may persist after normalization of serum levels of FT3, FT4, and TSH, which currently represent the gold standard in laboratory testing for diagnosis and evaluation of thyroid pathology. So, the metabolomics approach may contribute to integrate classical hormone assays and to determine the euthyroid status achievement with greater efficacy.

Shared and unique metabolic features of the malignant and benign thyroid lesions determined with use of 1H HR MAS NMR spectroscopy

The purpose of this work was to investigate the distinct and common metabolic features of the malignant and benign thyroid lesions in reference to the non-transformed tissue from the contralateral gland (chronic thyroiditis and colloid goiter). 1H HR MAS NMR spectra of 38 malignant lesions, 32 benign lesions and 112 samples from the non-tumoral tissue (32 from chronic thyroiditis and 80 samples from colloid goiter) were subjected both to multivariate and univariate analysis. The increased succinate, glutamine, glutathione, serine/cysteine, ascorbate, lactate, taurine, threonine, glycine, phosphocholine/glycerophosphocholine and decreased lipids were found in both lesion types in comparison to either colloid goiter or chronic thyroiditis. The elevated glutamate and choline, and reduced citrate and glucose were additionally evident in these lesions in reference to goiter, while the increased myo-inositol-in comparison to thyroiditis. The malignant lesions were characterized by the higher alanine and lysine levels than colloid goiter and thyroiditis, while scyllo-inositol was uniquely increased in the benign lesions (not in cancer) in comparison to both non-tumoral tissue types. Moreover, the benign lesions presented with the unique increase of choline in reference to thyroiditis (not observed in the cancerous tissue). The metabolic heterogeneity of the non-tumoral tissue should be considered in the analysis of metabolic reprogramming in the thyroid lesions.

The Association of Myo-Inositol and Selenium Contrasts Cadmium-Induced Thyroid C Cell Hyperplasia and Hypertrophy in Mice

Previous studies have demonstrated that, in addition to inducing structural changes in thyroid follicles, cadmium (Cd) increased the number of C cells. We examined the effects of myo-inositol (MI), seleno-L-methionine (Se), MI + Se, and resveratrol on C cells of mice exposed to cadmium chloride (Cd Cl2), as no data are currently available on the possible protective effects of these molecules. In contrast, we have previously shown this protective effect against CdCl2 on the thyroid follicles of mice. Ninety-eight C57 BL/6J adult male mice were divided into 14 groups of seven mice each: (i) 0.9% NaCl (vehicle; 1 ml/kg/day i.p.); (ii) Se (0.2 mg/kg/day per os); (iii) Se (0.4 mg/kg/day per os); (iv) MI (360 mg/kg/day per os); (v) Se (0.2 mg/kg/day) + MI; (vi) Se (0.4 mg/kg/day) + MI; (vii) resveratrol (20 mg/kg); (viii) CdCl2 (2 mg/kg/day i.p.) + vehicle; (ix) CdCl2 + Se (0.2 mg/kg/day); (x) CdCl2 + Se (0.4 mg/kg/day); (xi) CdCl2 + MI; (xii) CdCl2 + Se (0.2 mg/kg/day) + MI; (xiii) CdCl2 + Se (0.4 mg/kg/day) + MI; (xiv) CdCl2 + resveratrol (20 mg/kg). After 14 days, thyroids were processed for histological, immunohistochemical, and morphometric evaluation. Compared to vehicle, Cd significantly decreased follicle mean diameter, increased CT-positive cells number, area and cytoplasmic density, and caused the disappearance of TUNEL-positive C cells, namely, the disappearance of C cells undergoing apoptosis. Se at either 0.2 or 0.4 mg/kg/day failed to significantly increase follicular mean diameter, mildly decreased CT-positive cells number, area and cytoplasmic density, and was ineffective on TUNEL-positive C cells. Instead, MI alone increased significantly follicular mean diameter and TUNEL-positive cells number, and decreased significantly CT-positive cells number, area and cytoplasmic density. MI + Se 0.2 mg/kg/day or MI + Se 0.4 mg/kg/day administration improved all five indices more markedly. Indeed, follicular mean diameter and TUNEL-positive cells number increased significantly, while CT-positive cells number, area and cytoplasmic density decreased significantly. Thus, all five indices overlapped those observed in vehicle-treated mice. Resveratrol improved significantly all the considered parameters, with a magnitude comparable to that of MI alone. In conclusion, the association Myo + Se is effective in protecting the mouse thyroid from the Cd-induced hyperplasia and hypertrophy of C cells. This benefit adds to that exerted by Myo + Se on thyrocytes and testis.

The Role of Inositol in Thyroid Physiology and in Subclinical Hypothyroidism Management

Myo-Inositol (MYO) is the most abundant stereoisomer of inositols' family, cyclic polyols with 6 hydroxyl groups. Myo-Inositol has a relevant role in thyroid function and autoimmune diseases, as a precursor of phosphoinositides that takes part in the phosphatidylinositol (PI) signal transduction pathway. Among phosphoinositides, phosphatidylinositol 4,5- bisphosphate (PIP2) is the precursor of inositol triphosphates (IP3), second messenger of several hormones including thyroid-stimulating hormone (TSH). As a second messenger in the phospholipase C (PLC)-dependent inositol phosphate Ca²⁺/DAG pathway, Myo-Inositol is essential to produce H₂O₂ required for the synthesis of thyroid hormones. Consequently, depletion of Myo-Inositol or impaired inositol dependent TSH signaling pathway may predispose to the development of some thyroid diseases, such as hypothyroidism. Many clinical studies have shown that after treatment with Myo-Inositol plus Selenium (MYO+Se), TSH levels significantly decreased in patients with subclinical hypothyroidism with or without autoimmune thyroiditis. The TSH reduction was accompanied by a decline of antithyroid autoantibodies. Moreover, Myo-Inositol supplementation seemed to be involved also in the management of thyroidal benign nodules, with a possible effect in the size reduction. This review proposes a summary of the role of inositol, especially of Myo-Inositol, in the thyroidal physiology and its contribution on the management of some thyroid diseases.

Nutraceuticals in Thyroidology: A Review of in Vitro, and in Vivo Animal Studies

Nutraceuticals are defined as a food, or parts of a food, that provide medical or health benefits, including the prevention of different pathological conditions, and thyroid diseases, or the treatment of them. Nutraceuticals have a place in complementary medicines, being positioned in an area among food, food supplements, and pharmaceuticals. The market of certain nutraceuticals such as thyroid supplements has been growing in the last years. In addition, iodine is a fundamental micronutrient for thyroid function, but also other dietary components can have a key role in clinical thyroidology. Here, we have summarized the in vitro, and in vivo animal studies present in literature, focusing on the commonest nutraceuticals generally encountered in the clinical practice (such as carnitine, flavonoids, melatonin, omega-3, resveratrol, selenium, vitamins, zinc, and inositol), highlighting conflicting results. These experimental studies are expected to improve clinicians’ knowledge about the main supplements being used, in order to clarify the potential risks or side effects and support patients in their use.

D-Chiro-Inositol Improves Sperm Mitochondrial Membrane Potential: In Vitro Evidence

The use of inositols in endocrinological clinical practice is increasingly widespread. Most of the existing evidence concerns myoinositol (MYO), the most abundant form in nature, especially in women with polycystic ovarian syndrome. We have previously shown that MYO increases sperm motility in patients with asthenozoospermia by the increase of sperm mitochondrial membrane potential (MMP), a biofunctional sperm parameter closely associated to sperm motility. The aim of this study was to evaluate the effects of D-chiro-inositol (DCI), another biologically active isoform of inositols, on sperm MMP, as data on this matter has never been released so far. To accomplish this, semen samples from 15 patients with asthenozoospermia and 15 healthy normozoospermic men were incubated with increasing concentrations of DCI (0, 75, and 750 µg/mL) or phosphate buffer saline for 30 min. Incubation with DCI significantly improved sperm MMP at lower concentrations, and with shorter incubation length than those used in our similar MYO studies. In conclusion, these findings indicate that DCI positively impacts on sperm mitochondrial function in vitro. Studies aimed at assessing the role of DCI in the treatment of asthenozoospermia in-vivo are warranted.

Protective Effects of Myo-Inositol and Selenium on Cadmium-Induced Thyroid Toxicity in Mice

Cadmium (Cd) damages the thyroid gland. We evaluated the effects of myo-inositol (MI), seleno-L-methionine (Se) or their combination on the thyroids of mice simultaneously administered with Cd chloride (CdCl₂). Eighty-four male mice were divided into 12 groups (seven mice each). Six groups (controls) were treated with 0.9% NaCl (vehicle), Se (0.2 mg/kg/day), Se (0.4 mg/kg/day), MI (360 mg/kg/day), MI+Se (0.2 mg/kg) and MI+Se (0.4 mg/kg). The other six groups were treated with CdCl₂ (2 mg/kg), CdCl₂+MI, CdCl₂+Se (0.2 mg/kg), CdCl₂+Se (0.4 mg/kg), CdCl₂+MI+Se (0.2 mg/kg) and CdCl₂+MI+Se (0.4 mg/kg). An additional group of CdCl₂-challenged animals (n= 7) was treated with resveratrol (20 mg/kg), an effective and potent antioxidant. All treatments lasted 14 days. After sacrifice, the thyroids were evaluated histologically and immunohistochemically. CdCl₂ reduced the follicular area, increased the epithelial height, stroma, and cells expressing monocyte chemoattractant protein-1 (MCP-1) and C-X-C motif chemokine 10 (CXCL10). CdCl₂+Se at 0.2/0.4 mg/kg insignificantly reversed the follicular and stromal structure, and significantly decreased the number of MCP-1 and CXCL10-positive cells. CdCl₂+MI significantly reversed the thyroid structure and further decreased the number of MCP-1 and CXCL10-positive cells. CdCl₂+MI+Se, at both doses, brought all indices to those of CdCl₂-untreated mice. MI, particularly in association with Se, defends mice from Cd-induced damage. The efficacy of this combination was greater than that of resveratrol, at least when using the follicular structure as a read-out for a comparison. We suggest that the use of these nutraceuticals, more specifically the combination of MI plus SE, can protect the thyroid of Cd-exposed subjects.

Hashimotos' thyroiditis: Epidemiology, pathogenesis, clinic and therapy

Hashimoto's thyroiditis (HT), the most frequent autoimmune thyroid disorders (AITDs), is the leading cause of hypothyroidism in the iodine-sufficient areas of the world. About 20-30% of patients suffers from HT, whose cause is thought to be a combination of genetic susceptibility and environmental factors that causes the loss of immunological tolerance, with a consequent autoimmune attack to the thyroid tissue and appearance of the disease. The pathologic features of lymphocytic infiltration, especially of T cells, and follicular destruction are the histological hallmark of autoimmune thyroiditis (AIT), that lead to gradual atrophy and fibrosis. An important role in the immune-pathogenesis of AITDs is due to chemokines and cytokines. In about 20% of patients, AITDs are associated with other organ specific/systemic autoimmune disorders. Many studies have demonstrated the relationship between papillary thyroid cancer and AITD. The treatment of hypothyroidism, as result of AIT, consists in daily assumption of synthetic levothyroxine.

The effect of testosterone on thyroid autoimmunity in euthyroid men with Hashimoto's thyroiditis and low testosterone levels

WHAT IS KNOWN AND OBJECTIVE

Thyroid autoimmune diseases occur much more frequently in women than men. Unfortunately, no previous study has determined whether sex hormones produce any effect on thyroid antibody titres. The primary study aim was to assess whether exogenous testosterone affects thyroid autoimmunity in men with Hashimoto's thyroiditis and low testosterone levels.

METHODS

The study population consisted of 34 euthyroid men with autoimmune thyroiditis and testosterone deficiency. On the basis of patient preference, these patients were either treated with oral testosterone undecanoate (120 mg daily; n = 16) or remained untreated (n = 18). Circulating levels of thyrotropin, free thyroxine, free triiodothyronine, prolactin and total testosterone, as well as serum titres of thyroid peroxidase and thyroglobulin antibodies, were measured at the beginning of the study and 6 months later. The structure parameters of thyroid homeostasis (Jostel's thyrotropin index, SPINA-GT and SPINA-GD) were also calculated. Moreover, semen analyses were performed in eight patients in each group.

RESULTS AND DISCUSSION

In testosterone-naïve men, serum hormone levels and antibody titres remained at the similar levels throughout the study. Apart from increasing serum testosterone levels, testosterone undecanoate reduced titres of thyroid peroxidase and thyroglobulin antibodies and increased SPINA-GT. The drug produced a neutral effect on circulating levels of thyrotropin, free thyroid hormones, prolactin and testosterone, Jostel's thyrotropin index, SPINA-GD and semen parameters. Testosterone-induced changes in antibody titres correlated with the effect of treatment on SPINA-GT and with serum testosterone levels.

WHAT IS NEW AND CONCLUSION

This study is the first one to have shown that exogenous testosterone may have a protective effect on thyroid autoimmunity in men with Hashimoto's thyroiditis and testosterone deficiency.

Chemokines in hyperthyroidism

The term “hyperthyroidism” indicates a condition due to an exaggerate production of thyroid hormone; the most frequent cause is Graves’ disease (GD).

We review cytokines and chemokines in hyperthyroidism, with a special focus in GD.

In GD, recruited Th1 lymphocytes are responsible for enhanced IFN-γ and TNF-α production, which in turn stimulates Th1 chemokines release from thyrocytes, initiating and perpetuating the autoimmune process.

Circulating levels of these chemokines are associated with the active phase of GD.

Additional studies are necessary to investigate whether Th1 chemokines could be a novel therapeutic target in this disease.