Genotoxicity Evaluation of the Soybean Isoflavone Genistein in Human Papillary Thyroid Cancer Cells. Study of Its Potential Use in Thyroid Cancer Therapy.

Genistein is one of the several known isoflavonic phytoestrogens found in a number of plants, with soybeans and soy products being the primary food source. The aim of the study is to evaluate if genistein is able to exert antineoplastic action in primary human papillary thyroid cancer (PTC) cells. Thyroid tissues were treated with genistein (1-10-50-100 µM). Cell viability, proliferation, DNA primary damage and chromosomal damage were evaluated. An antiproliferative effect was induced by the highest doses of genistein, and such an effect was synergistically enhanced by the cotreatment with the antineoplastic drug sorafenib. Comet assay did not show any genotoxic effect in terms of primary DNA damage at all the times (4 and 24 h) and tested doses. A reduction of hydrogen peroxide-induced DNA primary damage in primary thyrocytes from PTC cells pretreated with genistein was observed. Data suggest that genistein exerts antineoplastic action, does not induce genotoxic effects while reduces oxidative-induced DNA damage in primary thyrocytes from PTC cells, supporting its possible use in therapeutic intervention.

CXCL8 and CXCL11 chemokine secretion in dermal fibroblasts is differentially modulated by vanadium pentoxide.

An increase in skin rashes or atopic dermatitis has been observed in individuals working with vanadium. However, to the best of our knowledge no in vivo or in vitro studies have evaluated the effect of exposure to vanadium in dermal fibroblasts. Cells viability and proliferation were assessed by WST­1 assay, cells were treated with increasing concentrations of V2O5 (1, 10 and 100 nM). CXCL8 and CXCL11 concentrations were measured in the supernatants using an ELISA assay. V2O5 was not observed as having a significant effect on dermal fibroblast's viability and proliferation. However, it was revealed that V2O5 was able to induce the secretion of CXCL8 and CXCL11 chemokines into dermal fibroblasts. V2O5 synergistically increased the effect of interferon (IFN)γ on CXCL11 secretion. In addition, V2O5 synergistically increased the effect of the tumor necrosis factor α on CXCL8 secretion and abolished the inhibitory effect of IFNγ. V2O5 induction of CXCL8 and CXCL11 chemokines may lead to the appearance and perpetuation of an inflammatory reaction into the dermal tissue. Further studies are required to evaluate dermal integrity and manifestations in subjects occupationally exposed, or living in polluted areas.

Vanadium pentoxide induces the secretion of CXCL9 and CXCL10 chemokines in thyroid cells.

Vanadium is a grey metal, existing in different states of oxidation, whose most common form in commercial products is vanadium pentoxide (V2O5). All vanadium compounds have been considered toxic. A carcinogenic role of vanadium on the thyroid has recently been proposed. However no in vivo or in vitro studies have evaluated thyroid disruption in humans and/or animals after exposure to vanadium. In the present study we evaluate the effect of V2O5 on proliferation, and chemokine secretion in normal thyrocytes. Our study demonstrated that V2O5 has no effect on thyroid follicular cell viability or proliferation, but it is able to induce the secretion of T-helper (Th)1 chemokines into the thyroid, synergistically increasing the effect of important Th1 cytokines such as interferon (IFN)γ and tumor necrosis factor (TNF)α. Through this process, V2O5 promotes the induction and perpetuation of an inflammatory reaction in the thyroid. Further studies are necessary to evaluate thyroid function, and nodules, in subjects occupationally exposed, or living in polluted areas.

Induction of Th1 chemokine secretion in dermal fibroblasts by vanadium pentoxide.

Vanadium is a soft, silvery­grey metal with a number of different oxidation states. The most common commercial form of vanadium is vanadium pentoxide (V2O5). All vanadium compounds are considered toxic. An increase in skin rashes has been observed in certain vanadium workers, including the development of atopic dermatitis. However, to the best of our knowledge, no prior in vivo or in vitro studies have evaluated the effect of vanadium exposure in human dermal fibroblasts. The present study evaluated the effect of V2O5 on proliferation and chemokine secretion in dermal fibroblasts. The results revealed that V2O5 had no significant effect on the viability or proliferation of fibroblasts, however it was able to induce the secretion of T­helper (Th)1 chemokines from dermal fibroblasts, synergistically increasing the effect of important Th1 cytokines, including interferon­Î³ and tumor necrosis factor­α. Through these processes, V2O5 may lead to the induction and perpetuation of an inflammatory reaction in dermal tissue. The induction and perpetuation of inflammation in the dermis and the variety of involved candidate genes may be at the base of V2O5­induced effects following occupational and environmental exposures. Further studies are necessary to evaluate dermal integrity and manifestations in subjects who are occupationally exposed, or living in polluted areas.

Both 3,5-diiodo-L-thyronine (T2) and T3 modulate glucose-induced insulin secretion.

3,5-diiodo-L-thyronine (T2), a naturally existing iodothyronine, has biological effects on humans, but no information is available on its action on pancreatic b-cells. We evaluated its effect vs triiodothyronine (T3), on glucose-induced insulin secretion in INS-1e cells, a rat insulinoma line, and on human islets. INS-1e were incubated in the presence/absence of T2 or T3 (0.1 nmol/L-10 µmol/L), and glucose (3.3, 7.5, 11.0, and 20 mmol/L). Insulin release and content (at 11.0 and 20 mmol/L glucose) were significantly (p less than 0.01) stimulated by 1-100 nmol/L T2 and 0.1 nmol/L-1.0 µmol/L T3, and inhibited with higher concentrations of both (1–10 µmol/L T2 and 10 µmol/L T3). Human islets were incubated with 3.3 mmol/L glucose in presence/absence of T3 or T2 (0.1 nmol/L, 0.1 µmol/L, and 1 µmol/L). T2 (0.1 nmol/L-0.1 µmol/L) significantly (p less than0.01) stimulated insulin secretion, while higher concentrations (1 µmol/L) inhibited it. A modest increase in insulin secretion was evidenced with 1 µmol/L T3. In conclusion, T2 and T3 have a direct regulatory role in insulin secretion, depending on their concentrations and the glucose level itself. At concentrations near the physiological range, T2 enhances glucose-induced insulin secretion in both rat b-cells and human islets.

Favorable effects of myo-inositol, selenomethionine or their combination on the hydrogen peroxide-induced oxidative stress of peripheral mononuclear cells from patients with Hashimoto's thyroiditis: preliminary in vitro studies.

OBJECTIVE: The aim of this study was to assess whether blood mononuclear cells (PBMC) from Hashimoto's thyroiditis (HT) and control women, were protected from in vitro H2O2-induced oxidative stress after addition of antioxidants. PATIENTS AND METHODS: PBMC, from 8 HT women and 3 healthy women (controls), were cultured in the presence of 200 µM H2O2 alone, with subsequent addition of myo-inositol (Myo) (0.25, 0.5, 1.0 µM), selenomethionine (SelMet) (0.25, 0.5, 1.0 µM), or their combination (0.25+0.25, 0.5+0.5, 1.0+1.0 µM). PBMC proliferation, vitality, genotoxicity (Comet score) and secretion in the medium of the chemokines CXCL10 [IP10], CCL2 e CXCL9 [MIG] were the indices measured. RESULTS: PBMC proliferation was decreased by H2O2 alone, and it decreased further and dose-dependently in either group (greatest decrease with Myo+SelMet in HT). H2O2 alone decreased vitality by 5% in controls and 10% in the HT group, but vitality was rescued by the three additions. The addition of H2O2 alone increased the Comet score at +505% above baseline in controls and +707% in HT women. In either group, each addition dose-dependently contrasted genotoxicity. Concentrations of chemokines in the medium were increased by H2O2 alone, and in HT women more than in controls. Each addition dose-dependently decreased these concentrations in either group, and often below baseline levels, with Myo+SelMet being the most potent addition (up to approximately -80% of baseline). CONCLUSIONS: The tested antioxidants exert beneficial effects on PBMC exposed in vitro to H2O2-induced oxidative stress in both control and HT women. Particularly, the association Myo+SelMet is the most effective. After the demonstration of a favorable in vitro outcomes in a large cohort of HT patients, we could predict favorable in vivo outcomes given by the same supplement. Thus, one can select HT patients with a high chance of benefit from supplementation.

Myo-inositol and selenium reduce the risk of developing overt hypothyroidism in patients with autoimmune thyroiditis.

OBJECTIVE: The beneficial effects obtained by myo-inositol in association with seleno-methionine in patients affected by subclinical hypothyroidism have been recently demonstrated. Here, we evaluate the immune-modulating effect of myo-inositol in association with seleno-methionine in patients with euthyroid autoimmune thyroiditis (AT). PATIENTS AND METHODS: Twenty-one consecutive Caucasian patients with newly diagnosed euthyroid chronic AT were evaluated. All subjects were treated with myo-inositol in association with selenium (600 mg/83 mg) tablets, twice per day, for six months. A complete thyroid assessment was done before the treatment, and after six months. RESULTS: After the treatment thyroid-stimulating hormone (TSH) levels significantly declined with respect to basal values, overall in patients with an initial TSH value in the high normal range (2.1

[Cryoglobulinemia and the α-chemokine IP-10]. / Crioglobulinemia e l'α-chemochina IP-10.

IFN-γ-induced protein 10 (IP-10) and its receptor, CXCR3 chemokine (C-X-C motif) receptor 3 (CXCR3), appear to contribute to the pathogenesis of HCV related mixed cryoglobulinemia (HCV+MC). The secretion of IP-10 by CD4+, CD8+ and natural killer (NK)-T cells is dependent on interferon (IFN)-γ, which is itself mediated by the interleukin (IL)-12 cytokine family. Under the influence of IFN-γ, IP-10 is secreted by several cell types including lymphocytes, hepatocytes, endothelial cells, fibroblasts, etc. In tissues, recruited T helper (Th) 1 lymphocytes may be responsible for enhanced IFN-γ and tumor necrosis factor (TNF)-α production, which in turn stimulates IP-10 secretion from the cells, therefore creating an amplification feedback loop, and perpetuating the autoimmune process. High levels circulation of IP-10 have been found in HCV+MC, especially in patients with clinically active vasculitis. Furthermore, HCV+MC patients with autoimmune thyroiditis (AT), have higher levels than those without AT. Further studies are needed to investigate interactions between chemokines and cytokines in the pathogenesis, and to evaluate whether IP-10 is a novel therapeutic target in HCV+MC.

IP-10 in autoimmune thyroiditis.

The interferon-γ-inducible protein 10 (IP-10) was initially identified as a chemokine that is induced by interferon (IFN)-γ. IP-10 exerts its function through binding to chemokine (C-X-C motif) receptor 3 (CXCR3). IP-10 and its receptor, CXCR3, appear to contribute to the pathogenesis of many autoimmune diseases, organ specific (such as type 1 diabetes, Graves' disease and ophthalmopathy), or systemic (such as systemic lupus erythematosus, mixed cryoglobulinemia, Sjogren syndrome, or systemic sclerosis). The secretion of IP-10 by (CD)4+, CD8+, and natural killer is dependent on IFN-γ. Under the influence of IFN-γ, IP-10 is secreted by thyrocytes. Determination of high level of IP-10 in peripheral fluids is therefore a marker of a T helper 1 orientated immune response. High levels of circulating IP-10, have been shown in patients with autoimmune thyroiditis (AT). Among patients with AT, IP-10 levels were significantly higher in those with a hypoechoic ultrasonographic pattern, which is a sign of a more severe lympho-monocytic infiltration, and in those with hypothyroidism. For these reasons, it has been postulated that IP-10 could be a marker of a stronger and more aggressive inflammatory response in the thyroid, subsequently leading to thyroid destruction and hypothyroidism. Further studies are needed to investigate whether IP-10 is a novel therapeutic target in AT.

[CXCR3 and CXCL10 in autoimmune thyroiditis]. / CXCR3 e CXCL10 nella tiroidite autoimmune.

The chemokine (C-X-C motif) ligand 10 (CXCL10, also called IP-10) was initially identified as a chemokine that is induced by interferon (IFN)-γ. CXCL10 exerts its function through binding to chemokine (C-X-C motif) receptor 3 (CXCR3). CXCL10 and its receptor, CXCR3, appear to contribute to the pathogenesis of many autoimmune diseases, organ specific (such as type 1 diabetes, Graves' disease and ophthalmopathy), or systemic (such as systemic lupus erythematosus, mixed cryoglobulinemia, Sjogren syndrome, or systemic sclerosis). The secretion of CXCL10 by CD4+, CD8+, and natural killer is dependent on IFN-γ. Under the influence of IFN-γ, CXCL10 is secreted by thyrocytes. Determination of high level of CXCL10 in peripheral fluids is therefore a marker of a T helper 1 orientated immune response. High levels of circulating CXCL10, have been shown in patients with autoimmune thyroiditis (AT). Among patients with AT, CXCL10 levels were significantly higher in those with a hypoechoic ultrasonographic pattern, that is a sign of a more severe lympho-monocytic infiltration, and in those with hypothyroidism. For these reasons it has been postulated that CXCL10 could be a marker of a stronger and more aggressive inflammatory response in the thyroid, subsequently leading to thyroid destruction and hypothyroidism. Further studies are needed to investigate whether CXCL10 is a novel therapeutic target in AT.

Type 1 diabetes and (C-X-C motif) ligand (CXCL) 10 chemokine.

The upregulation of (C-X-C motif) receptor 3 (CXCR3) and its ligand (C-X-C motif) ligand (CXCL)10 (CXCL10) has been documented in many autoimmune disorders. Many studies have suggested that the CXCL10/CXCR3 axis plays a critical role in the autoimmune process and in ß-cell destruction in Type 1 Diabetes (T1D). Serum CXCL10 level "Th1 chemokine" is high in T1D patients, and this suggests that CXCL10 may be a candidate for a predictive marker of T1D. Furthermore, serum CXCL10 levels measurement may be useful to assess the pathophysiology of the disease course in T1D. Blocking of the CXCL10 chemokine expression in newly onset of diabetes seems to be a possible approach for the therapy of T1D. Further studies are needed to investigate interactions between chemokines and cytokines in the pathogenesis of T1D.

Hepatitis C virus infection and type 2 diabetes.

Hepatitis C virus (HCV) infection and Type 2 diabetes mellitus (T2DM) are two worldwide, major public health problems with increasing complication and mortality rates. Many epidemiological studies have demonstrated the significant association between T2DM and chronic HCV infection. In this paper we have reviewed the increasing evidence linking HCV infection and DM in more than one field (epidemiology, pathogenesis, clinical aspects, prevention and treatment). We have considered T2DM, acute and chronic HCV infection, and cirrhotic patients. Moreover, we have considered some particular populations, solid organ transplant recipients or HCV/human immunodeficiency virus (HIV) coinfected patients. In the final part we have analyzed the potential effect of the association between HCV infection and the development of DM in term of outcome and possibilities for prevention and treatment.

HCV-related autoimmune disorders in HCV chronic infection.

Patients with hepatitis C virus (HCV) chronic infection may develop a great number of extrahepatic manifestations. Among these latter, mixed cryoglobulinemia (MC) represents the prototype of HCV-associated autoimmune-lymphoproliferative disorders. Other rheumatological manifestations of HCV chronic infection are Siögren syndrome, arthritis and CREST syndrome. Thyroid autoimmune disorders are among the most frequent manifestations of HCV chronic infections and are clinically relevant because of the association with thyroid dysfunctions and hypothyroidism. Autoimmune cytopenia is also reported in association with HCV infection. This paper reviews the association of HCV chronic infection with the above mentioned pathologies, and their immunopathogenesis.

Mixed cryoglobulinemia and thyroid autoimmune disorders.

In patients with hepatitis C virus-associated mixed cryoglobulinemia (MC+HCV) the following thyroid disorders are significantly more frequent than in HCV not infected controls: 1) high levels of serum anti-thyroperoxidase autoantibody (AbTPO), 2) high levels of serum AbTPO and/or anti-thyroglobulin (AbTg) autoantibody; 3) humoral and ultrasonographical signs of thyroid autoimmunity (35%); 4) prevalence of subclinical hypothyroidism (11%). Also, the prevalence of papillary thyroid cancer has been found higher in MC+HCV patients than in controls, in particular in patients with autoimmune thyroiditis. These results suggest a careful monitoring of thyroid function in these patients.

High circulating chemokines (C-X-C motif) ligand 9, and (C-X-C motif) ligand 11, in hepatitis C-associated cryoglobulinemia.

(C-X-C motif) ligand 9 and (C-X-C motif) ligand 11 (CXCL9 and CXCL11), are potent chemoattractants for activated T cells, and play an important role in T helper 1 (Th)1 cell recruitment in chronic hepatitis C. No study has evaluated CXCL9, together with CXCL11, circulating levels in patients with mixed cryoglobulinemia and hepatitis C (MC+HCV-p). The aim of the present study therefore was to measure serum CXCL9, and CXCL11 levels, in MC+HCV-p, and to relate the findings to the clinical phenotype. Serum CXCL9 and CXCL11 were measured in 71 MC+HCV-p and in matched controls. MC+HCV-p showed significantly higher mean CXCL9 and CXCL11 levels than controls (P less than 0.001, for both), in particular, in 32 patients with active vasculitis (P less than 0.001). By defining high CXCL9 or CXCL11 level as a value of at least 2 SD above the mean value of the control group ( greater than 100 pg/mL): 89 percent MC+HCV-p and 5 percent controls had high CXCL9 (P less than 0.0001, chi-square); 90 percent MC+HCV-p and 6 percent controls had high CXCL11 (P less than 0.0001, chi-square). In a multiple linear regression model of CXCL9 vs age, ALT, CXCL11, only CXCL11 was significantly (r = 0.452, P less than 0.0001) and independently related to CXCL9. Our study demonstrates in MC+HCV-p vs controls: (i) high serum CXCL9, and CXCL11, significantly associated with the presence of active vasculitis; (ii) a strong relationship between circulating CXCL9 and CXCL11. Future studies on a larger cohort of patients are needed to evaluate the relevance of serum CXCL9 and CXCL11 determination as clinico-prognostic marker of MC+HCV.

Peroxisome proliferator-activated receptor γ agonists reduce cell proliferation and viability and increase apoptosis in systemic sclerosis fibroblasts.

BACKGROUND: No study has evaluated the effect of the peroxisome proliferator-activated receptor γ (PPARγ) agonists on cell viability, proliferation and apoptosis in cultured systemic sclerosis (SSc) fibroblasts. OBJECTIVES: The effects of two pure PPARγ agonists (rosiglitazone and pioglitazone) in cultured SSc fibroblasts were evaluated and compared with effects in normal fibroblasts. METHODS: The study included evaluation of cell viability and proliferation (based on the cleavage of tetrazolium salts and measurement of absorbance of the cell proliferation reagent WST-1), and determination of cell apoptosis (by means of the Hoechst dye uptake). RESULTS: Rosiglitazone or pioglitazone (20µmolL(-1) ) significantly reduced cell proliferation (cell count of 75% and 83% compared with baseline, respectively, after 2h) and cell viability (absorbance reductions of 25% and 22% compared with baseline, respectively, after 2 h), and increased apoptosis (apoptotic cell percentages 9·9% and 8·6%, respectively, after 48h of incubation) in SSc fibroblasts, whereas they did not present a significant influence on control fibroblasts. CONCLUSIONS: The effects of rosiglitazone or pioglitazone shown on SSc fibroblasts raise the hypothesis of a therapeutic role for PPARγ agonists in patients affected by SSc.

High serum levels of CXC (CXCL10) and CC (CCL2) chemokines in untreated essential hypertension.

Hypertension has been suggested to exert pro-inflammatory actions through increased expression of several mediators, including chemokines. Chemokines are involved in inflammatory and autoimmune disorders, and in the formation of atherosclerotic lesions through promotion of inflammatory cell migration. The aim of this study is to evaluate the influence of high blood pressure on circulating levels of the prototype chemokines C-X-C motif ligand (CXCL)10 and C-C motif ligand (CCL)2 in 140 patients with essential hypertension not affected by thyroid disorders or overt autoimmune or inflammatory diseases, and 140 gender- and age-matched healthy controls. Mean CXCL10 and CCL2 levels were significantly higher in hypertensive patients than in controls. Among hypertensive patients, chemokines levels were higher in those with systo-diastolic hypertension compared to those with isolated systolic hypertension. In a multiple linear regression model using CXCL10 or CCL2 as dependent variables and age, body mass index, glycemia, serum creatinine, high-density-lipoprotein (HDL) and low-density-lipoprotein (LDL) cholesterol, triglycerides, and systolic or diastolic blood pressure values as covariates, only systolic or diastolic blood pressure values were significantly related to CXCL10 or CCL2 levels. In conclusion, this study demonstrates increased circulating levels of the prototype chemokines CXCL10 and CCL2 in patients with hypertension.

IFN-γ and TNF-α induce a different modulation of interleukin-6 in systemic sclerosis fibroblasts compared to healthy controls.

BACKGROUND: To our knowledge, no previous study has evaluated the effect of interferon (IFN)-γ, tumour necrosis factor (TNF)-α, or their combination on the prototype proinflammatory cytokine interleukin (IL)-6 in primary cultured fibroblasts from patients with systemic sclerosis (SSc) at an early stage of the disease. METHODS: Fibroblast cultures from five SSc patients (disease duration < 2 years) and five healthy controls were evaluated for the basal production of IL-6, and after stimulation with TNF-α or IFN-γ, alone or combined. RESULTS: The fibroblasts from SSc patients produced higher levels of IL-6 in basal condition than controls [617 ± 173 vs. 213 ± 123 pg/mL; analysis of variance (ANOVA), p < 0.001]. TNF-α was able to dose-dependently induce IL-6 in SSc (609 ± 184, 723 ± 243, 1079 ± 297, 1436 ± 326 pg/mL, with TNF-α 0, 1, 5, 10 ng/mL, respectively) but not in control fibroblasts, whereas IFN-γ was unable to induce IL-6. Furthermore, the combination of IFN-γ and TNF-α induced a stronger secretion of IL-6 in SSc fibroblasts (ANOVA, p < 0.0001), without effect in controls. CONCLUSIONS: SSc fibroblasts participate in the self-perpetuation of inflammation by releasing IL-6, under the influence of TNF-α and/or IFN-γ.

3,5-diiodo-L-thyronine increases resting metabolic rate and reduces body weight without undesirable side effects.

Recently, it was demonstrated that 3,5-diiodo-L-thyronine (T2) stimulates the resting metabolic rate (RMR), and reduces body-weight gain of rats receiving a high-fat diet. The aim of this study is to examine the effects of chronic T2 administration on basal metabolic rate and body weight in humans. Two euthyroid subjects volunteered to undergo T2 administration. Body weight, body mass index, blood pressure, heart rate, electrocardiogram, thyroid and liver ultrasonography, glycemia, total cholesterol, triglycerides, free T3 (FT3), free T4 (FT4), T2, thyroid stimulating hormone (TSH) and RMR were evaluated at baseline and at the end of treatment. RMR increased significantly in each subject. After continuing the T2 treatment for a further 3 weeks (at 300 mcg/day), body weight was reduced significantly (p<0.05) (about 4 percent), while the serum levels of FT3, FT4 and TSH, were unchanged. No side effects were observed at the cardiac level in either subject. No significant change was observed in the same subjects taking placebo.