Assessment of metabolic changes within normal appearing gray and white matter in children with growth hormone deficiency: magnetic resonance spectroscopy and hormonal correlation

The metabolic alterations within the normal appearing brain in patients with Hashimoto's thyroiditis are correlated with hormonal changes

Hashimoto's thyroiditis (HT) is the most common autoimmune disease in humans usually associated with subsequent hypothyroidism. The purpose of the study was to assess metabolic alterations within the normal appearing brain in subjects with HT using MR spectroscopy (MRS) and to correlate MRS measurements with hormonal concentrations. Fifty-five HT patients (mean age 43.5 yrs) and 30 healthy controls (mean age 42.5 yrs) were examined with the use of a 1.5 T MR scanner. There were no signs of central nervous system involvement in the studied group. The MRS examinations were performed using the single voxel method. The voxels were placed in the left parietal white matter (PWM) and the posterior cingulate gyrus (PCG). The NAA/Cr, Cho/Cr, and mI/Cr ratios were calculated. The correlations between metabolite ratios and hormonal concentrations (TSH, fT3, fT4) as well as anti-TG and anti-TPO levels were also assessed. We found significantly (p < 0.05) decreased NAA/Cr ratios in PCG and PWM in HT subjects compared to the control group. There were no other significant differences in metabolite ratios. We observed significant positive correlations between the NAA/Cr ratio in PCG as well as the PWM and fT3 level. There was also a significant negative correlation between the Cho/Cr ratio in the PCG and fT4 level. MRS could be a sensitive biomarker capable of depicting early cerebral metabolic disturbances associated with HT. Our findings may indicate the reduction of neuronal activity within the normal appearing brain in patients with HT as well as suggesting that there is a possible biological association between thyroid dysfunction and cerebral metabolic changes.

Visual and brainstem auditory evoked potentials in HCV-infected patients before and after interferon-free therapy - A pilot study

INTRODUCTION

The aim of this study was to investigate brain bioelectrical activity disturbances in HCV-positive patients before and 24 weeks after interferon-free therapy (DAA), using visual (VEP) and brainstem (BAEP) evoked potentials and advanced magnetic resonance techniques.

MATERIALS AND METHODS

11 HCV-infected patients (6 women, 5 men, mean age 51 years old) and 30 healthy controls, sex and age-matched, were studied. Clinical neurological examinations, VEP, BAEP, diffusion tensor imaging (DTI) and perfusion weighted imaging (PWI) were performed.

RESULTS

11 patients achieved a sustained viral response, and liver fibrosis regression in APRI and in elastography were observed. The mean P100 latency was significantly shorter in HCV-patients after therapy compared to the values before treatment (p<0.05). The mean wave BAEP V latency and I-V interpeak latency were significantly longer in the HCV-infected patients before therapy compared to HCV-patients after therapy.

CONCLUSIONS

This study confirms that treatment with DAA in patients with chronic HCV infection positively affects the bioelectrical activity of the brain. An increase in the amplitude of EP after treatment indicates an improvement in the activity of the cerebral cortex. EP examination may be a useful method of assessing the function of the nervous system before and after antiviral treatment.

Metabolic alterations in paediatric GH deficiency

Growth hormone (GH) has a large number of metabolic effects, involving lipid and glucose homoeostasis, lean and fat mass. Growth hormone deficiency (GHD) is associated with a metabolic profile similar to the Metabolic Syndrome which is characterized by dyslipidemia, insulin resistance, haemostatic alterations, oxidative stress, and chronic inflammation. GH replacement treatment in GHD children improves these cardiovascular risk factors, while cessation of GH is associated with a deterioration of most of these risk factors. However, it is unclear whether the changes of these risk factors are associated with an increased risk of cardiovascular diseases especially after discontinuing GH treatment. GH treatment itself can lead to insulin resistance, which probably also influences the cardiovascular health status. Therefore, longitudinal studies with the primary outcome cardiovascular diseases are needed in GHD children. Furthermore, new approaches such as metabolomic studies might be helpful to understand the relationship between GHD, GH treatment, and cardiovascular diseases.