Anticonvulsant and Neuroprotective Effects of the Thyroid Hormone Metabolite 3-Iodothyroacetic Acid.

BACKGROUND: 3-Iodothyroacetic acid (TA1) is among the thyroid hormone (T3) metabolites that can acutely modify behavior in mice. This study aimed to investigate whether TA1 is also able to reduce neuron hyper-excitability and protect from excitotoxic damage. METHODS: CD1 male mice were treated intraperitoneally with saline solution or TA1 (4, 7, 11, or 33 µg/kg) before receiving 90 mg/kg pentylenetrazole subcutaneously. The following parameters were measured: latency to first seizure onset, number of mice experiencing seizures, hippocampal levels of c-fos, and PI3K/AKT activation levels. Organotypic hippocampal slices were exposed to vehicle or to 5 µM kainic acid (KA) in the absence or presence of 0.01-10 µM TA1. In another set of experiments, slices were exposed to vehicle or 5 µM KA in the absence or presence of 10 µM T3, 3,5,3'-triiodothyroacetic acid (TRIAC), T1AM, thyronamine (T0AM), or thyroacetic acid (TA0). Neuronal cell death was measured fluorimetically. The ability of TA1 and T3, TRIAC, T1AM, T0A, and TA0 to activate the PI3K/AKT cascade was evaluated by Western blot. The effect of TA1 on KA-induced currents in CA3 neurons was evaluated by patch clamp recordings on acute hippocampal slices. RESULTS: TA1 (7 and 11 µg/kg) significantly reduced the number of mice showing convulsions and increased their latency of onset, restored pentylenetrazole-induced reduction of hippocampal c-fos levels, activated the PI3K/AKT, and reduced GSK-3ß activity. In rat organotypic hippocampal slices, TA1 reduced KA-induced cell death by activating the PI3K/AKT cascade and increasing GSK-3ß phosphorylation levels. Protection against KA toxicity was also exerted by T3 and other T3 metabolites studied. TA1 did not interact at KA receptors. Both the anticonvulsant and neuroprotective effects of TA1 were abolished by pretreating mice or organotypic hippocampal slices with pyrilamine, an histamine type 1 receptor antagonist (10 mg/kg or 1 µM, respectively). CONCLUSIONS: TA1 exerts anticonvulsant activity and is neuroprotective in vivo and in vitro. These findings extend the current knowledge on the pharmacological profile of TA1 and indicate possible novel clinical use for this T3 metabolite.

Identification of the Nicotinamide Salvage Pathway as a New Toxification Route for Antimetabolites.

Interest in the modulation of nicotinamide adenine dinucleotide (NAD) metabolome is gaining great momentum because of its therapeutic potential in different human disorders. Suppression of nicotinamide salvage by nicotinamide phosphoribosyl transferase (NAMPT) inhibitors, however, gave inconclusive results in neoplastic patients because several metabolic routes circumvent the enzymatic block converging directly on nicotinamide mononucleotide adenylyl transferases (NMNATs) for NAD synthesis. Unfortunately, NMNAT inhibitors have not been identified. Here, we report the identification of Vacor as a substrate metabolized by the consecutive action of NAMPT and NMNAT2 into the NAD analog Vacor adenine dinucleotide (VAD). This leads to inhibition of both enzymes, as well as NAD-dependent dehydrogenases, thereby causing unprecedented rapid NAD depletion, glycolytic block, energy failure, and necrotic death of NMNAT2-proficient cancer cells. Conversely, lack of NMNAT2 expression confers complete resistance to Vacor. Remarkably, Vacor prompts VAD formation and growth suppression in NMNAT2-positive neuroblastoma and melanoma xenografts. Our data show the first evidence of harnessing the entire nicotinamide salvage pathway for antimetabolic strategies.

Dexpramipexole improves bioenergetics and outcome in experimental stroke.

BACKGROUND AND PURPOSE: Dexpramipexole, a drug recently tested in patients with amyotrophic lateral sclerosis (ALS,) is able to bind F1Fo ATP synthase and increase mitochondrial ATP production. Here, we have investigated its effects on experimental ischaemic brain injury. EXPERIMENTAL APPROACH: The effects of dexpramipexole on bioenergetics, Ca2+ fluxes, electrophysiological functions and death were evaluated in primary neural cultures and hippocampal slices exposed to oxygen-glucose deprivation (OGD). Effects on infarct volumes and neurological functions were also evaluated in mice following proximal or distal middle cerebral artery occlusion (MCAo). Distribution of dexpramipexole within the ischaemic brain was evaluated by means of mass spectrometry imaging. KEY RESULTS: Dexpramipexole increased mitochondrial ATP production in cultured neurons or glia and reduces energy failure, prevents intracellular Ca2+ overload and affords cytoprotection when cultures are exposed to OGD. This compound also counteracted ATP depletion, mitochondrial swelling, anoxic depolarization, loss of synaptic activity and neuronal death in hippocampal slices subjected to OGD. Post-ischaemic treatment with dexpramipexole, at doses consistent with those already used in ALS patients, reduced brain infarct size and ameliorated neuroscore in mice subjected to transient or permanent MCAo. Notably, the concentrations of dexpramipexole reached within the ischaemic penumbra equalled those found neuroprotective in vitro. CONCLUSION AND IMPLICATIONS: Dexpramipexole, a compound able to increase mitochondrial F1Fo ATP-synthase activity reduced ischaemic brain injury. These findings, together with the excellent brain penetration and favourable safety profile in humans, make dexpramipexole a drug with realistic translational potential for the treatment of stroke. LINKED ARTICLES: This article is part of a themed section on Inventing New Therapies Without Reinventing the Wheel: The Power of Drug Repurposing. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.2/issuetoc.

CoQ10-containing eye drops prevent UVB-induced cornea cell damage and increase cornea wound healing by preserving mitochondrial function.

PURPOSE: We evaluated the potential protective effects of Coenzyme Q10 (CoQ10) on human corneal cells and rabbit eyes after ultraviolet B (UVB) exposure and a model of wound healing in rabbit eyes after corneal epithelium removal. METHODS: Human corneal epithelium cells (HCE) were exposed to a source of UVB radiation (312 nM) in the presence of different CoQ10 concentrations or vehicle. The mitochondrial function and cell survival were evaluated by means of 3-(4,5-dimethylthiazole-2-yl)2,5-diphenyl-tetrazolium (MTT) reduction and lactic dehydrogenase (LDH) release. Furthermore, quantitation of oxygen consumption and mitochondrial membrane potential were conducted. In vivo rabbit models were adopted to evaluate the effect of CoQ10 on UVB-induced conjunctival vessel hyperemia and corneal recovery after ethanol induced corneal lesion. RESULTS: In UVB-exposed HCE cells, CoQ10 addition led to an increased survival rate and mitochondrial function. Furthermore, oxygen consumption was maintained at control levels and adenosine triphosphate (ATP) decline was completely prevented in the CoQ10-treated cells. Interestingly, in an in vivo model, CoQ10 was able dose-dependently to reduce UVB-induced vessel hyperemia. Finally, in a model of corneal epithelium removal, 12 hours from surgery, animals treated with CoQ10 showed a reduction of damaged area in respect to vehicle controls, which lasted until 48 hours. CONCLUSIONS: We demonstrated that CoQ10 reduces corneal damages after UVB exposure in vivo and in vitro by preserving mitochondrial function. Also, for the first time to our knowledge we showed that the administration of CoQ10 after corneal epithelium removal promotes corneal wound healing.

Romiplostim for severe thrombocytopenia in the treatment of chronic hepatitis C virus infection: a new option for clinicians?

We describe a case of a 64-year-old man with a history of ITP which had required several treatments including splenectomy, and with chronic hepatitis C virus (HCV) infection untreated due to severe thrombocytopenia. In March 2011, platelet count was 14,000/mmc and a thrombopoietic therapy with romiplostim was initiated at the dose of 2 mcg/kg/week that was increased to 8 mcg/kg/week. At week 32, platelet count was 65,000/mmc and an anti-HCV therapy with peginterferon and ribavirin was then started. At baseline laboratory tests indicated AST 99IU/l, ALT 125UI/l, HCV_RNA 3,220 UI/ml and HCV genotype 2a/2c. An early virological response (EVR) with normalization of transaminases in the course of antiviral therapy, such as a sustained virological response (SVR) after its interruption were recorded. Therefore a satisfactory platelet count (range 54.000-179.000/mmc) at the dose of 4 mcg/week during antiviral therapy, such as at the dose of 2 mcg/kg/week after antiviral interruption (range 65.000-292.000/mmc) was recorded. Romiplostim proved effective and safe in the course of antiviral treatment. Therefore it permitted the start of anti-HCV therapy despite severe thrombocytopenia and also avoided any peg-interferon dosage modification or discontinuation. Further prospective studies in larger patient cohort should be encouraged to validate this strategy.

Ectopic thyroid gland: description of a case and review of the literature.

The clinical occurrence of ectopic thyroid gland is an infrequently encountered condition, resulting from a developmental abnormality during the migration of the thyroid anlage from the floor of the primitive foregut to its final position in the neck. It can be found along the way of thyroid descent, in the midline, or laterally in the neck or even in the mediastinum or under the diaphragm. This condition is often asymptomatic, whereas symptoms could be related to ectopic thyroid size, to its relationships with surrounding organs or to diseases affecting the ectopic thyroid in the same way they involve orthotopic glands. Sometimes, a growing mass can lead to the clinical suspicion of a tumor disease. On the other hand, thyroid ectopy must be distinguished from metastasis of thyroid cancer. Scintigraphy and ultrasonography are the main diagnostic means for evaluating ectopic thyroid tissue, whereas fine needle aspiration could be useful in the presence of a nodular ectopic gland or when the coexistence of an orthotopic thyroid can arise the suspicion of a metastasis from a thyroid cancer. Surgical removal is indicated in symptomatic cases, whereas radioiodine ablation is reserved to recurrent disease. In this paper we report an emblematic case of ectopic thyroid gland and a review of the literature dealing with this condition.

Parathyroid hormone determination in ultrasound-guided fine needle aspirates allows the differentiation between thyroid and parathyroid lesions: our experience and review of the literature.

In many cases, it is difficult or even impossible to distinguish parathyroid lesions from thyroid ones at ultrasound as well as at scintiscan and even at cytology, because they often share common features. The aim of this study was to evaluate the role of Parathyroid Hormone (PTH) determination in the aspirates in the differential diagnosis of parathyroid from thyroid lesions in an area of mild iodine deficiency and high prevalence of thyroid nodules. Forty-six consecutive patients were suspected to have one or more nodule(s) of parathyroid origin because of their position in the posterior aspect of thyroid lobes and/or their shape and echo-pattern at ultrasound examination. In 13 cases, there were also laboratory findings suggestive for primary hyperparathyroidism, with clinical evidence in 6 of these patients. A total of 55 lesions suspected to be of parathyroid origin were selected. After obtaining cytological preparations, the needle used to perform the fine-needle aspirate (FNA) was washed using 1 ml of normal saline. Intact PTH determination in the washout was done whereas the evaluation was performed directly in the aspirated fluid in case of cystic lesions. The values of PTH in the aspirates ranged from 6.7 to 16640 pg/ml. Sixteen patients underwent surgical intervention and the histological examination of the 23 operated lesions previously submitted to FNA-PTH showed 11 parathyroid adenomas, 5 hyperplasic parathyroid lesions and 7 benign thyroid nodules. A strong positive correlation between high levels of PTH in the aspirate and the histological findings of parathyroid lesions was found. A value over 245 pg/ml was constantly associated to the parathyroid lesions. Our results confirmed the high accuracy of FNA-PTH determination in differentiating parathyroid lesions from thyroid nodules and this is of special value in an area of mild iodine deficiency with a high prevalence of thyroid nodules.

A long diagnostic delay in patients with Hereditary Haemorrhagic Telangiectasia: a questionnaire-based retrospective study.

BACKGROUND: The difficulty in establishing a timely correct diagnosis is a relevant matter of concern for several rare diseases. Many rare-disease-affected patients suffer from considerable diagnostic delay, mainly due to their poor knowledge among healthcare professionals, insufficient disease awareness among patients' families, and lack of promptly available diagnostic tools. Hereditary Haemorrhagic Telangiectasia (HHT) is an autosomal-dominantly inherited vascular dysplasia, affecting 1:5,000-10,000 patients. HHT is characterized by high variability of clinical manifestations, which show remarkable overlapping with several common diseases. AIM: To perform a detailed analysis concerning the diagnostic time lag occurring in patients with HHT, defined as the time period spanning from the first clinical manifestation to the attainment of a definite, correct diagnosis. METHODS: A questionnaire was administered to the HHT patients previously recruited from 2000 and 2009. Clinical onset, first referral to a physician for disease manifestations, and first correct diagnosis of definite HHT were collected. Eventual misdiagnosis at first referral and serious complications occurring throughout the time elapsing between disease onset and definite diagnosis were also addressed. RESULTS: In the 233 respondents, the clinical onset of disease occurred at an age of 14.1 yrs, while the age of first referral and the age of first definite diagnosis of HHT were 29.2 yrs and 40.1 yrs, respectively. Only 88/233 patients received a correct diagnosis at first counseling. Thus, the diagnostic time lag, represented by the time elapsing from disease onset and first definite diagnosis of HHT, proved to be 25.7 yrs. Twenty-two patients suffered from severe complications during this time interval. The diagnostic delay was significantly longer (p < 0.001) in index patients (first patients who attained definite HHT diagnosis in a given family) than in non-index patients (relative of index patients). The diagnostic time lag was also significantly associated with education grade (p < 0.001). CONCLUSIONS: Our data report for the first time a systematic inquiry of diagnostic delay in HHT showing that patients receive a definite diagnosis only after nearly three decades from disease onset. Concerted efforts are still to be made to increase awareness of this disease among both families and physicians.

Differentiated thyroid carcinoma and intestinal polyposis syndromes.

Familial Adenomatous Polyposis, Cowden's Syndrome, and Peutz-Jeghers Syndrome are well known as Intestinal Polyposis Syndromes, inherited conditions characterized by the development of polyps of the gastro-intestinal tract in association with extra-intestinal manifestations, in particular malignant tumors at different sites. Thyroid carcinoma is sometimes a part of the clinical picture of these syndromes. The aim of this paper is to review the literature dealing with the association between differentiated thyroid carcinomas and Intestinal Polyposis Syndromes in order to point out peculiar aspects, providing suggestions for the screening and the management of thyroid tumors in these patients.

Papillary thyroid carcinoma in Peutz-Jeghers syndrome.

BACKGROUND: Peutz-Jeghers syndrome (PJS) is a rare dominantly inherited disease characterized by the association of gastrointestinal hamartomatous polyposis, mucocutaneous hyperpigmentation, and increased risk of cancer at different target organs. Its occurrence with differentiated thyroid cancer, particularly papillary thyroid carcinoma (PTC), even if rare, has been described. SUMMARY: We here present a case of PTC observed in a PJS patient and a review of the literature aiming at discussing the utility of thyroid surveillance in the management of these patients. A 22-year-old woman presenting with hyperpigmented lesions of the lips and hamartomatous polyps in the stomach, duodenum, jejunum, and ileum, leading to the suspicion of PJS, was submitted to genetic analysis. Mutation scanning of the Liver Kinase B1 (LKB1) gene identified the presence of the truncating mutation E265X, thus confirming the clinical diagnosis. Beside the endoscopic, radiologic, and echographic evaluations required by the standard surveillance guidelines, the patient had a neck ultrasound (US), which showed a 5×4×6 mm hypoechoic nodule in the right thyroid lobe. The nodule contained microcalcifications and a perinodular vascular pattern. The cytological preparations derived from US-guided fine-needle aspiration biopsy of the nodule demonstrated the presence of PTC. The patient underwent a video-assisted total thyroidectomy and the histological examination revealed a follicular variant of papillary microcarcinoma. Radioactive iodine therapy was not performed because of the small size of the lesion. The patient was started on levothyroxine therapy to keep the serum thyrotropin levels suppressed. Both the sequencing and the multiplex ligation-dependent probe amplification analysis could not identify any LKB1 mutation in the tumor specimen, and the methylation-specific polymerase chain reaction assay excluded hypermethylation of the LKB1 promoter as the mechanism of inactivation for the remaining normal allele in the tumor. CONCLUSIONS: Although other mechanisms of LKB1 silencing may be responsible for its inactivation in the thyroid cancer, we cannot rule out that the occurrence of thyroid carcinoma could be a coincidental finding in this patient. However, the case here presented suggests that US of the thyroid could possibly become an integral part of the evaluation and the follow-up program adopted for PJS patients.

Varicella zoster virus encephalitis during treatment with anti-tumor necrosis factor-alpha agent in a psoriatic arthritis patient.

The introduction of targeted immunotherapies has greatly improved the therapeutic options of several inflammatory diseases such as psoriatic arthritis. However treatment-related opportunistic infections and viral reactivations may still occur. We describe a case of varicella zoster virus (VZV) encephalitis due to the reactivation of latent VZV infection during a long therapy with the anti-tumor necrosis factor-alpha (TNF-alpha) drug Adalimumab. The low incidence of VZV encephalitis in patients treated with biological agents does not justify VZV serological screening in these subjects, but careful monitoring of the patients is recommended to recognize early signs and symptoms of herpes zoster to start prompt antiviral therapy to prevent associated complications.

Effect of low-density lipoprotein apheresis on circulating endothelial progenitor cells in familial hypercholesterolemia.

BACKGROUND: Long-term treatment with low-density lipoprotein (LDL) apheresis (LA) has been shown to reduce the incidence of cardiovascular events in patients affected by familial hypercholesterolemia (FH). Data from experimental studies suggest that circulating endothelial progenitor cells (EPCs) can repair the vascular lesions caused by atherosclerosis. Since a reduction of these cells has been demonstrated to predict atherosclerosis progression, the aim of this study was to verify whether LA can increase the percentage of EPCs. METHODS: In 15 patients affected by FH periodically treated with LA, the percentage of EPCs was determined before and after performing LA, and compared with the values of 15 control subjects and 15 hypercholesterolemic patients treated with statins. RESULTS: Significant differences were found in FH patients between the pre-apheresis percentages of CD34+/KDR+, defined as EPCs by a wide consensus of opinion, and the values found 24 h after the procedures (0.00868 +/- 0.003 vs. 0.01009 +/- 0.002%, p < 0.005). Instead, the percentages of CD34+/KDR+/CD133+, considered as an immature subset of EPCs, remained substantially unchanged. However, a significant reduction in the percentage of EPCs was observed in both patient groups as compared to the controls, at all the assessment times. CONCLUSION: In the short-term LA seems to stimulate mobilization of CD34+/KDR+ cells. Hypercholesterolemic patients show a lower percentage of EPCs than controls. There were no differences in the EPCs percentages between the 2 patients groups, despite the fact that LDL cholesterol levels were higher in the group undergoing LA.

Association of a wide invasive malignant thymoma with myastenia gravis and primary hyperparathyroidism due to parathyroid adenoma: case report and review of the literature.

There are few cases described in the world literature reporting an association of thymoma (with myasthenia gravis or not) with hyperparathyroidism. In these cases the hyperparathyroidism was due to the presence of an adenoma or hyperplasic parathyroid tissue either in the cervical region or in an ectopic intrathymic location.(12345) In other cases the syndrome of hypercalcemia was due to the secretion of parathyroid-related protein (PTHRP) (6) or parathyroid hormone (PTH) (7) by the thymoma itself. We report the first case, at the best of our knowledge, of a wide invasive malignant thymoma (type B3), associated with myasthenia gravis and hyperparathyroidism caused by parathyroid adenoma.

Prospective study of post-partum thyroid immune dysfunctions in type 1 diabetic women and in a healthy control group living in a mild iodine deficient area.

Second to diabetes mellitus, thyroid diseases are the most common endocrinopathies seen in pregnancy. The incidence of post-partum thyroid dysfunction (PPTD) in women with type 1 diabetes mellitus is three-fold increased. We determined the incidence of thyroid abnormalities in a well-defined group of young subjects with type 1 diabetes and in an age-matched healthy controls during and six months after pregnancy in an area of mild iodine deficiency. Twenty-five out of twenty-eight pregnant women completed the study. Fifteen were affected by type 1 diabetes and ten were controls. Our protocol of study consisted of four evaluations of each subject: in the first, in the second trimester, at delivery and six months after. At each control the patients were submitted to physical examination, thyroid ultrasonography, and determination of fT3, fT4, TSH, Antithyroglobulin antibodies (TgAbs), Antithyroperoxidase antibodies (TPOAbs). The variation of thyroid volume is statistically significant in both the diabetics and in the controls during the different times of observations. Four out of the fifteen diabetic pregnant patients (27%) developed a thyroid disease: two cases of post-partum thyroiditis (PPT) and two cases of euthyroid benign nodular goiter, as confirmed by cytological examination. Two out ten controls (20%) developed positive antibodies (TPO Abs and TgAbs) since the first observation and showed an autoimmune thyroiditis six months after delivery. Both of them showed a familial history of thyroid disease. Our study suggests that in an area of mild iodine deficiency the incidence of thyroid autoimmunity in pregnant women is similar, whether diabetic or not; moreover, thyroid volume is increasing in the diabetics as much as in the non diabetics during pregnancy.

Rendu-Osler-Weber disease: experience with 56 patients.

Rendu-Osler-Weber disease, or hereditary hemorrhagic telangiectasia (HHT), is an autosomal dominant disease characterized by systemic vascular dysplasia. The prevalence varies and ranges, according to region, from 1/3500 to 1/5000. Data concerning Italy are not available. The diagnosis is based on the following criteria: family history, epistaxis, telangiectases and visceral arteriovenous malformations. The diagnosis is to be considered definite if three criteria are present and suspected if two criteria are present. From September 2000 to March 2002, 100 patients (63 males, 37 females, mean age 45.5 +/- 17.3 years) potentially affected by HHT were evaluated in the HHT Center of the "Augusto Murri" Internal Medicine Section at the University of Bari (on a day-hospital or hospitalization basis). The diagnosis of HHT was confirmed in 56 patients and suspected in 10. Magnetic resonance imaging revealed cerebral arteriovenous malformations in 8.5% of patients. In 14.6% of patients contrast echocardiography revealed pulmonary arteriovenous malformations subsequently confirmed at multislice computed tomography in all cases but one. In 48.2% of subjects hepatic vascular malformations were revealed by echo color Doppler ultrasonography, whereas abdominal multislice computed tomography was positive in 63.8% of patients. In 64% of the 25 patients, who underwent endoscopy, gastric telangiectases were found. In 3 out of 6 patients presenting with pulmonary arteriovenous malformations, embolotherapy was performed with success. In our patients, the use of tranexamic acid caused a reduction in the frequency of epistaxis. The future objectives of the HHT Center of Bari are to increase knowledge of the disease, to cooperate with other centers with the aim of increasing the number of patients studied and to avoid the limits of therapeutic and diagnostic protocols of a rare disease such as HHT.