Huntington's Disease Progression and Caregiver Burden.

Huntington's disease (HD) is a neurodegenerative, progressive disorder conditioned by a mutation in the HTT gene. Its progression is dependent on the causative mutation extension. Caregivers of individuals affected by HD, most often patients' relatives, are burdened with the care. This study aims to assess the caregivers' burden cross-sectionally and longitudinally and look for biological and clinical patients-related burdening factors. In total, 144 caregiver-patient pairs observed annually for up to 8 years were included in the study. In all of the patients, demographic data were collected, Unified Huntington's Disease Rating Scale (UHDRS) assessments were conducted, and disease burden (DB) was calculated when caregivers were assessed in Caregiver Burden Inventory (CBI). Caregivers' burden measured in CBI at the first visit reached 18.7 ± 18.4 scores. Longitudinal observation showed no evidence for any discrepancy between clinical progression measured in UHDRS, nor biological progression measured in DB and the caregivers' burden progression measured in CBI. Caregivers were burdened mostly by patients' dependence and a discrepancy between reality and life expectations. This study indicates factors to be addressed to reduce caregivers' burden. Strict relation between caregivers' burden and biological and clinical progression denies conception of overloaded with care tasks or adaptation to the burden.

Structural Abnormalities of the Optic Nerve and Retina in Huntington's Disease Pre-Clinical and Clinical Settings.

Huntington's disease (HD) is a fatal neurodegenerative disorder caused by a polyglutamine expansion in the huntingtin protein. HD-related pathological remodelling has been reported in HD mouse models and HD carriers. In this study, we studied structural abnormalities in the optic nerve by employing Spectral Domain Optical Coherence Tomography (SD-OCT) in pre-symptomatic HD carriers of Caucasian origin. Transmission Electron Microscopy (TEM) was used to investigate ultrastructural changes in the optic nerve of the well-established R6/2 mouse model at the symptomatic stage of the disease. We found that pre-symptomatic HD carriers displayed a significant reduction in the retinal nerve fibre layer (RNFL) thickness, including specific quadrants: superior, inferior and temporal, but not nasal. There were no other significant irregularities in the GCC layer, at the macula level and in the optic disc morphology. The ultrastructural analysis of the optic nerve in R6/2 mice revealed a significant thinning of the myelin sheaths, with a lamellar separation of the myelin, and a presence of myelonoid bodies. We also found a significant reduction in the thickness of myelin sheaths in peripheral nerves within the choroids area. Those ultrastructural abnormalities were also observed in HD photoreceptor cells that contained severely damaged membrane disks, with evident vacuolisation and swelling. Moreover, the outer segment of retinal layers showed a progressive disintegration. Our study explored structural changes of the optic nerve in pre- and clinical settings and opens new avenues for the potential development of biomarkers that would be of great interest in HD gene therapies.

Is deep brain stimulation effective in Huntington's Disease? - a systematic literature review.

INTRODUCTION: Huntington's Disease (HD) is an autosomal dominant neurodegenerative disorder. Substantial for a diagnosis of the disease are motor disorders, with chorea as a hallmark symptom. Other disease manifestations include cognitive dysfunction and psychiatric disorders. Currently, pharmacological treatment plays the most important role in the therapy of HD patients. However, deep brain stimulation (DBS) is considered a potential therapeutic option. AIM OF THE STUDY: Systematic review of current literature on DBS efficacy and safety in the management of motor, behavioural and cognitive functions in patients with HD. MATERIAL AND METHODS: A systematic review was conducted with the use of the Scopus database and the following search criteria: TITLE (huntington*) AND TITLE-ABS-KEY ('deep brain stimulation' OR 'neuromodulation'). Our search criteria included original studies with at least five patients, reporting any motor, cognitive and/or behavioural, and functional assessment data with at least a 6-month follow-up. Finally, four selected publications were analysed. RESULTS: In all analysed publications, we found a statistically significant improvement of Unified Huntington's Disease Rating Scale (UHDRS) chorea subscore by an average of 40, to over 60% after DBS implantation. Heterogeneous results were obtained for UHDRS total motor score. DBS did not improve functional capacity of HD patients in the analysed studies. We found no systematic assessment concerning the effect of DBS in HD on behaviour, cognition or speech. CONCLUSIONS: DBS implantation could be considered as a therapeutic option for patients with severe, drug-resistant chorea. However, the evidence for this is limited. To date, no high-quality data based on randomised controlled trials supports the long-term safety and efficacy of DBS in HD. This treatment option should therefore currently be considered as investigational.

Melatonin secretion in migraine patients: the current state of knowledge.

INTRODUCTION: Zdunska et al. [1] present the results of a pilot study exploring changes in melatonin serum concentration in migraine patients, and the clinical implications of these changes. CLINICAL REFLECTIONS: Melatonin secretion may be altered for several reasons, and migraine is one of those clinical conditions where melatonin secretion can be changed. Correlations between migraine clinical phenotype and melatonin secretion pat-terns may bring exciting results. CLINICAL IMPLICATIONS: Alterations in melatonin secretion in migraine has not been explained. Studies which aim at exploring the mechanism(s) of action of melatonin secretion in migraine patients may provide an insight into the pathogenesis of migraine and contribute to effective treatment options.

A study in a Polish ataxia cohort indicates genetic heterogeneity and points to MTCL1 as a novel candidate gene.

Inherited ataxias are a group of highly heterogeneous, complex neurological disorders representing a significant diagnostic challenge in clinical practice. We performed a next-generation sequencing (NGS) analysis in 10 index cases with unexplained progressive cerebellar ataxia of suspected autosomal recessive inheritance. A definite molecular diagnosis was obtained in 5/10 families and included the following diseases: autosomal recessive spastic ataxia of Charlevoix-Saguenay, POLR3B-related hypomyelinating leukodystrophy, primary coenzyme Q10 deficiency type 4, Niemann-Pick disease type C1 and SYNE1-related ataxia. In addition, we found a novel homozygous MTCL1 loss of function variant p.(Lys407fs) in a 23-year-old patient with slowly progressive cerebellar ataxia, mild intellectual disability, seizures in childhood and episodic pain in the lower limbs. The identified variant is predicted to truncate the protein after first 444 of 1586 amino acids. MTCL1 encodes a microtubule-associated protein highly expressed in cerebellar Purkinje cells; its knockout in a mouse model causes ataxia. We propose MTCL1 as a candidate gene for autosomal recessive cerebellar ataxia in humans. In addition, our study confirms the high diagnostic yield of NGS in early-onset cerebellar ataxias, with at least 50% detection rate in our ataxia cohort.

An impaired metabolism of nucleotides underpins a novel mechanism of cardiac remodeling leading to Huntington's disease related cardiomyopathy.

Huntington's disease (HD) is mainly thought of as a neurological disease, but multiple epidemiological studies have demonstrated a number of cardiovascular events leading to heart failure in HD patients. Our recent studies showed an increased risk of heart contractile dysfunction and dilated cardiomyopathy in HD pre-clinical models. This could potentially involve metabolic remodeling, that is a typical feature of the failing heart, with reduced activities of high energy phosphate generating pathways. In this study, we sought to identify metabolic abnormalities leading to HD-related cardiomyopathy in pre-clinical and clinical settings. We found that HD mouse models developed a profound deterioration in cardiac energy equilibrium, despite AMP-activated protein kinase hyperphosphorylation. This was accompanied by a reduced glucose usage and a significant deregulation of genes involved in de novo purine biosynthesis, in conversion of adenine nucleotides, and in adenosine metabolism. Consequently, we observed increased levels of nucleotide catabolites such as inosine, hypoxanthine, xanthine and uric acid, in murine and human HD serum. These effects may be caused locally by mutant HTT, via gain or loss of function effects, or distally by a lack of trophic signals from central nerve stimulation. Either may lead to energy equilibrium imbalances in cardiac cells, with activation of nucleotide catabolism plus an inhibition of re-synthesis. Our study suggests that future therapies should target cardiac mitochondrial dysfunction to ameliorate energetic dysfunction. Importantly, we describe the first set of biomarkers related to heart and skeletal muscle dysfunction in both pre-clinical and clinical HD settings.

Melatonin and cortisol profiles in patients with pituitary tumors.

The optic tract section at the optic chiasm is expected to disturb the suprachiasmatic nucleus (SCN) rhythm, circadian rhythm and melatonin secretion rhythms in humans, although detailed studies have never been conducted. The aim of this paper was to describe melatonin and cortisol profiles in patients with a pituitary tumor exerting optic chiasm compression. Six patients with pituitary tumors of different size, four of whom had significant optic chiasm compression, were examined. In each brain, MRI, an ophthalmological examination including the vision field and laboratory tests were performed. Melatonin and cortisol concentrations were measured at 22:00 h, 02:00 h, 06:00 h, and 10:00 h in patients lying in a dark, isolated room. One of the four cases with significant optic chiasm compression presented a flattened melatonin rhythm. The melatonin rhythm was also disturbed in one patient without optic chiasm compression. Larger tumors may play a role in the destruction of neurons connecting the retina with the suprachiasmatic nucleus (SCN) and breaking of basic way for inhibiting effect to the SCN from the retina.

A study of molecular changes relating to energy metabolism and cellular stress in people with Huntington's disease: looking for biomarkers.

Huntington's disease (HD) is a neurodegenerative disorder characterized by a progressive motor and cognitive decline and the development of psychiatric symptoms. The origin of molecular and biochemical disturbances in HD is a mutation in the HTT gene, which is autosomally dominantly inherited. The altered huntingtin protein is ubiquitously expressed in the CNS, as well as in peripheral tissues. In this study we measured the metabolism changes in gene transcription in blood of HD gene carriers (premanifest and manifest combined) versus 28 healthy controls. The comparison revealed statistically significant Global Pattern Recognition Fold Change (FC) for 6 mRNA transcripts, reflecting an increase of: MAOB (FC = 3.07; p = 0.0005) which encodes an outer mitochondrial membrane-bound enzyme called monoamine oxidase type B; TGM2 (FC = 1.8; p = 0.02) encoding a transglutaminase 2 that mediates cellular stress; SLC2A4 (FC = 1.64; p = 0.02) solute carrier family 2 (facilitated glucose transporter) member 4; branched chain ketoacid dehydrogenase kinase (BCKDK) (FC = 1.34; p = 0.02); decrease of LDHA (FC = -1.16; p = 0.03) lactate dehydrogenase A; and brain-derived neurotrophic factor (BDNF) (FC = -2,11; p = 0.03). These distinguished changes coincided with HD progress. The analyses of gene transcription levels in sub-cohorts confirmed these changes and also revealed 28 statistically significant FCs of gene transcripts involved in ATP production and BCAA metabolism.

Prevalence of Non-psychiatric Comorbidities in Pre-symptomatic and Symptomatic Huntington's Disease Gene Carriers in Poland.

Huntington's disease (HD) is monogenic neurodegenerative disorder caused by CAG expansions within the Huntingtin gene (Htt); it has a prevalence of 1 in 10,000 worldwide and is invariably fatal. Typically, healthy individuals have fewer than 35 CAG repeats, while the CAG expansions range from 36 to ~200 in HD patients. The hallmark of HD is neurodegeneration, especially in the striatal nuclei, basal ganglia and cerebral cortex, leading to neurological symptoms that involve motor, cognitive, and psychiatric events. However, HD is a complex disorder that may also affect peripheral organs, so it is possible that HD patients could be affected by comorbidities. Hence, we investigated the prevalence of comorbid conditions in HD patients (pre-symptomatic and symptomatic groups) and compared the frequency of those conditions to a control group. Our groups represent 65% of HD gene carriers registered in Poland. We identified 8 clusters of comorbid conditions in both HD groups, namely: musculoskeletal, allergies, cardiovascular, neurological, gastrointestinal, thyroid, psychiatric, and ophthalmologic. We found that HD patients have a significantly higher percentage of co-existing conditions in comparison to the control group. Among the 8 clusters of diseases, musculoskeletal, psychiatric, and cardiovascular events were significantly more frequent in both pre- and symptomatic HD patients, while neurological and gastrointestinal clusters showed significantly higher occurrence in the HD symptomatic group. A greater recognition of comorbidity in HD might help to better understand health outcomes and improve clinical management.

[Vertebral arteries dissection as a rare cause of central nervous system ischemia]. / Rozwarstwienie tetnic kregowych jako rzadka przyczyna niedokrwienia osrodkowego ukladu nerwowego.

However rare, dissection of extracranial cerebral arteries is one of the most often causes of ischemic stroke in young people. Early diagnosis and treatment promote artery recanalization that results in total symptom regression. The proper diagnosis is in many cases is difficult. The reason is the variety of causative factors, clinical symptoms and difficulty of direct dissected vertebral arteries visualisation in common Duplex-Doppler examination. In our article we present 3 causes of vertebral arteries dissection. We would like to call your attention to consider this causative factor in differentiation diagnostics of central nervous system ischemia. This complication may occur not only due to a communication accident, but also during playing tennis and bowling.

The contribution of gender differences in motor, behavioral and cognitive features to functional capacity, independence and quality of life in patients with Huntington's disease.

INTRODUCTION: Huntington's disease (HD) is a neurodegenerative autosomal dominant disorder affecting patients' motor, behavioral and cognitive domains leading to total dependency for activities of daily life. This study compares whether gender differences in motor, cognitive and behavioral symptoms affect function and how functional impairment affects quality of life (QoL). METHODS: We recruited 2191 subjects from the REGISTRY data base that provides personal data, HD age of onset, visit date, CAG mutation size, UHDRS and TFC scores from at least one visit. For 1166 participants SF-36 was also available. We calculated Spearman coefficients for correlations between particular symptomatic domains and functional scales, Fisher z-transform was used to test whether differences in correlations between genders were statistically significant. Simultaneous linear regression with least-square fit method was used to determine for how much variability in functional scales the particular symptomatic domains are responsible. ANOVA was used to look for QoL differences between TFC-stage based groups. Baseline statistics showed no significant differences between genders. RESULTS: Motor, cognitive and behavioral domains contributed significantly to function and independence. The motor domain contributed most followed by the cognitive and to a lesser degree by the behavioral domain. Motor symptoms correlated more with functional ability and influenced function variability more in women than in men. The decline in functional abilities correlated significantly with QoL decline. CONCLUSION: Motor symptoms have highest impact on function in HD, moreover these symptoms affect female function and independence more than males. Results indicate that symptomatic treatment targeting motor symptoms is needed to improve HD function and QoL.

Update on Huntington's disease: advances in care and emerging therapeutic options.

INTRODUCTION: Huntington's disease (HD) is the most common hereditary neurodegenerative disorder. Despite the fact that both the gene and the mutation causing this monogenetic disorder were identified more than 20 years ago, disease-modifying therapies for HD have not yet been established. REVIEW: While intense preclinical research and large cohort studies in HD have laid foundations for tangible improvements in understanding HD and caring for HD patients, identifying targets for therapeutic interventions and developing novel therapeutic modalities (new chemical entities and advanced therapies using DNA and RNA molecules as therapeutic agents) continues to be an ongoing process. The authors review recent achievements in HD research and focus on approaches towards disease-modifying therapies, ranging from huntingtin-lowering strategies to improving huntingtin clearance that may be promoted by posttranslational HTT modifications. CONCLUSION: The nature and number of upcoming clinical studies/trials in HD is a reason for hope for HD patients and their families.

HDAC4 as a potential therapeutic target in neurodegenerative diseases: a summary of recent achievements.

For the past decade protein acetylation has been shown to be a crucial post-transcriptional modification involved in the regulation of protein functions. Histone acetyltransferases (HATs) mediate acetylation of histones which results in the nucleosomal relaxation associated with gene expression. The reverse reaction, histone deacetylation, is mediated by histone deacetylases (HDACs) leading to chromatin condensation followed by transcriptional repression. HDACs are divided into distinct classes: I, IIa, IIb, III, and IV, on the basis of size and sequence homology, as well as formation of distinct repressor complexes. Implications of HDACs in many diseases, such as cancer, heart failure, and neurodegeneration, have identified these molecules as unique and attractive therapeutic targets. The emergence of HDAC4 among the members of class IIa family as a major player in synaptic plasticity raises important questions about its functions in the brain. The characterization of HDAC4 specific substrates and molecular partners in the brain will not only provide a better understanding of HDAC4 biological functions but also might help to develop new therapeutic strategies to target numerous malignancies. In this review we highlight and summarize recent achievements in understanding the biological role of HDAC4 in neurodegenerative processes.

Association of influenza incidence with multiple sclerosis onset.

The aim of this study was to investigate the environmental factors influencing the tangible changes in the incidence of multiple sclerosis (MS) over a period of the past 30 years in the town Gniezno, Poland. We analysed many environmental factors to which the whole population was exposed in the respective period. The following factors were considered: viral infections (influenza, measles, varicella, rubella, mumps), atmospheric air pollution and climate conditions. A positive correlation has been found between the incidence of influenza and the incidence of MS in the same year (r = 0.37; p = 0.04) as well as with the MS incidence assessed after 5 years (r = 0.64; p = 0.0005). No significant correlation has been found between the incidence of MS and other investigated environmental factors. These results support the hypothesis that influenza infection could precipitate MS onset.

[Clinical picture of patients with Huntington's disease in relation to the number of trinucleotide CAG repeats in IT-15 gene]. / Obraz kliniczny pacjentów z choroba Huntingtona w zestawieniu z liczba powtórzen trójnukleotydu CAG w genie IT-15.

Huntington's disease (HD) is a neurological condition of progressive course that results from abnormally increased number of CAG repeats within IT-15 gene, coding for huntington. The main symptoms consist of choraetic movements, dementia, and characteropathy. The aim of the present study was to search for possible correlation between the age of the onset of HD, time from the onset, clinical status of the patients, and CAG repeats number. Ten patients were studied altogether. Modified UHDRS (MUHDRS) was applied for the estimation of patients' clinical status. The number of CAG repeats in examination of the IT-15 gene was determined by polymerase chain reaction (PCR) and separation of radioisotope labelled PCR product against DNA size marker in polyacrylamide gel. A negative significant correlation was found between the CAG repeats number and the disease onset age (r = -0.67; p < 0.05) and MUHDRS score (r = 0.75; p < 0.05), as well. Negative significant correlation between time from the onset and MUHDRS score (r = -0.95; p < 0.05) and negative correlation between summarised: time from the onset and CAG number on the one site and MUHDRS on the other (p = -0.91) were found, as well. Our findings indicate an interdependence between CAG repeats number within the IT-15 gene, the course of the disease and the clinical status of HD patients.

Skeletal muscle pathology in Huntington's disease.

Huntington's disease (HD) is a hereditary neurodegenerative disorder caused by the expansion of a polyglutamine stretch within the huntingtin protein (HTT). The neurological symptoms, that involve motor, cognitive and psychiatric disturbances, are caused by neurodegeneration that is particularly widespread in the basal ganglia and cereberal cortex. HTT is ubiquitously expressed and in recent years it has become apparent that HD patients experience a wide array of peripheral organ dysfunction including severe metabolic phenotype, weight loss, HD-related cardiomyopathy and skeletal muscle wasting. Although skeletal muscles pathology became a hallmark of HD, the mechanisms underlying muscular atrophy in this disorder are unknown. Skeletal muscles account for approximately 40% of body mass and are highly adaptive to physiological and pathological conditions that may result in muscle hypertrophy (due to increased mechanical load) or atrophy (inactivity, chronic disease states). The atrophy is caused by degeneration of myofibers and their replacement by fibrotic tissue is the major pathological feature in many genetic muscle disorders. Under normal physiological conditions the muscle function is orchestrated by a network of intrinsic hypertrophic and atrophic signals linked to the functional properties of the motor units that are likely to be imbalanced in HD. In this article, we highlight the emerging field of research with particular focus on the recent studies of the skeletal muscle pathology and the identification of new disease-modifying treatments.

Huntington' disease--imbalance of amino acid levels in plasma of patients and mutation carriers.

Determination of the plasma amino acid (AA) levels in Huntington's disease (HD) can make it possible to find the metabolic markers used in early diagnosis. The aim of the presented study was to determine the AA profile in plasma samples from HD patients and presymptomatic carriers, compared to healthy subjects. The AA profile was analyzed with HPLC. The study concerned 59 participants: 30 subjects with abnormal CAG repeats expansion (>36) in the HTT gene, and 29 healthy subjects. Each participant was analyzed with regard to the parameters characterizing the metabolic state and protein metabolism, such as: urea, creatinine, glucose, total protein, TSH (thyroid-stimulating hormone), cortisol, ESR (erythrocyte sedimentation rate), and CRP (C-reactive protein). Simple statistical comparisons showed 5 AA to be significantly lower in the HD group, compared to the control group, i.e.: Asn, His, Leu, Ser, Thr. Creatinine and creatinine clirens were found to be lower in the HD group, compared to controls, while ESR was noticed to be higher. As a result of Canonical Discriminant Analysis, 5 of all AA assayed (Leu, Gln, Asn, Ser and Lys) were selected as variables that allow distinguishing between HD patients and healthy subjects with 75% of correctness. Concerning AA profile and biochemical markers, Canonical Discriminant Analysis detected a panel of variables (Ser, Asn, Gln, Orn, Pro, Arg, Met, Cit, Val, TSH, glucose, urea, creatinine clirens, total protein, cortisol, CRP) distinguishing HD from the control group, with 90% of correctness. Among all the parameters tested, Asn and Ser were revealed in all statistical analyses and could be considered as potential plasma HD biomarkers.