Molecular factors in migraine

Migraine is a common neurological disorder that affects 11% of adults worldwide. This disease most likely has a neurovascular origin. Migraine with aura (MA) and more common form - migraine without aura (MO) - are the two main clinical subtypes of disease. The exact pathomechanism of migraine is still unknown, but it is thought that both genetic and environmental factors are involved in this pathological process. The first genetic studies of migraine were focused on the rare subtype of MA: familial hemiplegic migraine (FHM). The genes analysed in familial and sporadic migraine are: MTHFR, KCNK18, HCRTR1, SLC6A4, STX1A, GRIA1 and GRIA3. It is possible that migraine is a multifactorial disease with polygenic influence.Recent studies have shown that the pathomechanisms of migraine involves both factors responsible for immune response and oxidative stress such as: cytokines, tyrosine metabolism, homocysteine; and factors associated with pain transmission and emotions e.g.: serotonin, hypocretin-1, calcitonin gene-related peptide, glutamate. The correlations between genetic variants of the HCRTR1 gene, the polymorphism 5-HTTLPR and hypocretin-1, and serotonin were observed. It is known that serotonin inhibits the activity of hypocretin neurons and may affect the appearance of the aura during migraine attack.The understanding of the molecular mechanisms of migraine, including genotype-phenotype correlations, may contribute to finding markers important for the diagnosis and treatment of this disease.

Analysis of PRKN Variants and Clinical Features in Polish Patients with Parkinson's Disease

The etiology of Parkinson's disease (PD) is still unclear, but mutations in PRKN have provided some biological insights. The role of PRKN mutations and other genetic variation in determining the clinical features of PD remains unresolved. The aim of the study was to analyze PRKN mutations in PD and controls in the Polish population and to try to correlate between the presence of genetic variants and clinical features. We screened for PRKN mutations in 90 PD patients and 113 controls and evaluated clinical features in these patients. We showed that in the Polish population 4% of PD patients had PRKN mutations (single or with additional polymorphism) while single heterozygous polymorphisms (S167N, E310D, D394N) of PRKN were present in 21% of sporadic PD. Moreover, 5% PD patients had more than one PRKN change (polymorphisms and mutations). Detected PRKN variants moderately correlated with PD course and response to L-dopa. It also showed that other PARK genes (SNCA, HTRA2, SPR) mutations probably may additionally influence PD risk and clinical features. PRKN variants are relatively common in our Polish series of patients with PD. Analysis of the PRKN gene may be useful in determining clinical phenotype, and helping with diagnostic and prognostic procedures in the future.

The Immunology of Neuromyelitis Optica-Current Knowledge, Clinical Implications, Controversies and Future Perspectives

Neuromyelitis optica (NMO) is an autoimmune, demyelinating disorder of the central nervous system (CNS) with typical clinical manifestations of optic neuritis and acute transverse myelitis attacks. Previously believed to be a variant of multiple sclerosis (MS), it is now considered an independent disorder which needs to be differentiated from MS. The discovery of autoantibodies against aquaporin-4 (AQP4-IgGs) changed our understanding of NMO immunopathogenesis and revolutionized the diagnostic process. AQP4-IgG is currently regarded as a specific biomarker of NMO and NMO spectrum disorders (NMOsd) and a key factor in its pathogenesis. Nevertheless, AQP4-IgG seronegativity in 10%-25% of NMO patients suggests that there are several other factors involved in NMO immunopathogenesis, i.e., autoantibodies against aquaporin-1 (AQP1-Abs) and antibodies against myelin oligodendrocyte glycoprotein (MOG-IgGs). This manuscript reviews current knowledge about NMO immunopathogenesis, pointing out the controversial issues and showing potential directions for future research. Further efforts should be made to broaden our knowledge of NMO immunology which could have important implications for clinical practice, including the use of potential novel biomarkers to facilitate an early and accurate diagnosis, and modern treatment strategies improving long-term outcome of NMO patients.

Burden in caregivers of long-term stroke survivors: Prevalence and determinants at 6 months and 5 years after stroke

OBJECTIVES

To assess the prevalence of considerable burden among caregivers of stroke survivors at 6 months (Time 1) and 5 years after stroke (Time 2), to analyse changes in burden severity over time and to identify factors associated with the burden.

METHODS

Eighty eight patient/caregiver pairs were assessed. Caregiver burden was measured with the Caregiver Burden Scale. Socio-demographic, stroke-related and psychological characteristics were analysed as potential determinants of the burden. Exact multiple logistic regression was used to identify the predictive factors.

RESULTS

Considerable burden was reported by 44% of the caregivers at Time 1 and 30% at Time 2. The burden was independently associated with caregivers' sense of coherence and amount of time spent caregiving at Time 1, and with caregivers' anxiety at Time 2.

CONCLUSIONS

A significant proportion of the caregivers experienced considerable burden in the post-acute and chronic phases of stroke, although this proportion declined over time. Several characteristics were associated with the increased burden at different time points. All the independent predictors related to aspects of the carers.

PRACTICE IMPLICATIONS

Programmes including education about coping strategies and time management, as well as respite care provision, could be beneficial and might help to reduce the burden of caregiving.

Pulsatility index in carotid arteries is increased in levothyroxine-treated Hashimoto disease

The aim of this case-control study was to evaluate carotid hemodynamic variables and traditional cardiovascular risk factors in women with Hashimoto thyroiditis (HT). The study group consisted of 31 females with HT on levothyroxine (L-T4) and 26 euthyroid women with HT without L-T4 matched for age and body mass index (BMI) as controls. Carotid intima-media thickness (CIMT), carotid extra-media thickness (CEMT), and pulsatility indexes in common carotid artery (PI CCA) and in internal carotid artery (PI ICA) were measured. BMI, waist circumference, lipid profile, fasting glucose and insulin levels, and parameters of thyroid function [TSH, free thyroxine (FT4) and antithyroperoxidase antibodies (TPOAbs)] were assessed. The study and the control groups did not differ in age, BMI, waist circumference, lipid profile, fasting glucose, and insulin levels. Results are expressed as median (IQR). Treated HT group had higher FT4 levels than nontreated [17.13 (5.11) pmol/l vs. 14.7 (2.27) pmol/l; p=0.0011] and similar TSH [1.64 (2.08) IU/ml vs. 2.07 (3.14) IU/ml; p=0.5915]. PI CCA and PI ICA were higher in the study group than in controls (p=0.0224 and p=0.0477, respectively). The difference remained statistically significant for PI ICA and PI CCA after adjustment for other variables (coefficient=0.09487; standard error=0.04438; p=0.037 and coefficient=0.1786; standard error=0.0870; p=0.0449, respectively). CIMT and CEMT were similar in both groups (p=0.8746 and p=0.0712, respectively). Women with HT on L-T4 replacement therapy have increased PI in common and internal carotid arteries than nontreated euthyroid HT patients. Therefore, it seems that hypothyroidism, but not autoimmune thyroiditis per se, influences arterial stiffness.

Randomized phase 1b trial of MOR103, a human antibody to GM-CSF, in multiple sclerosis

Objectives:

To determine the safety, pharmacokinetics (PK), and immunogenicity of the recombinant human monoclonal antibody MOR103 to granulocyte-macrophage colony-stimulating factor (GM-CSF) in patients with multiple sclerosis (MS) with clinical or MRI activity.

Methods:

In this 20-week, randomized, double-blind, placebo-controlled phase 1b dose-escalation trial (registration number NCT01517282), adults with relapsing-remitting MS (RRMS) or secondary progressive MS (SPMS) received an IV infusion of placebo (n = 6) or MOR103 0.5 (n = 8), 1.0 (n = 8), or 2.0 (n = 9) mg/kg every 2 weeks for 10 weeks. Patients had to have ≤10 gadolinium (Gd)-enhancing brain lesions on T1-weighted MRI at baseline. The primary objective was safety.

Results:

Most treatment-emergent adverse events (TEAEs) were mild to moderate in severity. The most frequent was nasopharyngitis. Between-group differences in TEAE numbers were small. There were no TEAE-related trial discontinuations, infusion-related reactions, or deaths. Nine patients experienced MS exacerbations: 3, 5, 1, and 0 patient(s) in the placebo, 0.5, 1.0, and 2.0 mg/kg groups, respectively. A few T1 Gd-enhancing lesions and/or new or enlarging T2 lesions indicative of inflammation were observed in all treatment groups. No clinically significant changes were observed in other clinical assessments or laboratory safety assessments. No anti-MOR103 antibodies were detected. PK evaluations indicated dose linearity with low/no drug accumulation over time.

Conclusions:

MOR103 was generally well-tolerated in patients with RRMS or SPMS. No evidence of immunogenicity was found.

Classification of evidence:

This phase 1b study provides Class I evidence that MOR103 has acceptable tolerability in patients with MS.

Neurological complications of underwater diving

The diver's nervous system is extremely sensitive to high ambient pressure, which is the sum of atmospheric and hydrostatic pressure. Neurological complications associated with diving are a difficult diagnostic and therapeutic challenge. They occur in both commercial and recreational diving and are connected with increasing interest in the sport of diving. Hence it is very important to know the possible complications associated with this kind of sport. Complications of the nervous system may result from decompression sickness, pulmonary barotrauma associated with cerebral arterial air embolism (AGE), otic and sinus barotrauma, high pressure neurological syndrome (HPNS) and undesirable effect of gases used for breathing. The purpose of this review is to discuss the range of neurological symptoms that can occur during diving accidents and also the role of patent foramen ovale (PFO) and internal carotid artery (ICA) dissection in pathogenesis of stroke in divers.

Caregiving burden and its determinants in Polish caregivers of stroke survivors

INTRODUCTION

Despite the growing body of literature on the consequences of providing non-professional care to stroke survivors, the determinants of caregiving burden are still not fully recognized. Identification of significant determinants can facilitate caregiver intervention programs. The aim of this study was to evaluate the level of burden borne by caregivers of stroke patients and to identify the most important determinants of burden at 6 months after hospitalization.

MATERIAL AND METHODS

Data were collected from 150 pairs of stroke patients/caregivers. Caregiver burden was assessed on the Caregiver Burden scale (CB). Several characteristics were measured as potential predictors of the burden. Special attention was paid to the caregiver's sense of coherence (SOC) and anxiety. Regression analysis was employed to test the hypothesized relationships between these variables and the burden.

RESULTS

Forty-seven percentage of the caregivers reported a substantial burden (severe or moderate). Caregiver SOC (p < 0.001), anxiety (p < 0.001) and the patients' functional status (p < 0.001) were the most important predictors of the overall burden and the most consistent predictors of the majority of aspects included in the CB scale. Caregiver health, patient's gender, time spent caregiving and social support were also factors related to the burden. The identified predictors explained 67% of the variance in the overall burden.

CONCLUSIONS

Clinicians and other professionals should focus on the coping abilities of caregivers, their emotional state and the level of patients' dependency, as these are the vital and modifiable factors affecting caregiver burden following stroke.

Genetic variants in diseases of the extrapyramidal system

Knowledge on the genetics of movement disorders has advanced significantly in recent years. It is now recognized that disorders of the basal ganglia have genetic basis and it is suggested that molecular genetic data will provide clues to the pathophysiology of normal and abnormal motor control. Progress in molecular genetic studies, leading to the detection of genetic mutations and loci, has contributed to the understanding of mechanisms of neurodegeneration and has helped clarify the pathogenesis of some neurodegenerative diseases. Molecular studies have also found application in the diagnosis of neurodegenerative diseases, increasing the range of genetic counseling and enabling a more accurate diagno-sis. It seems that understanding pathogenic processes and the significant role of genetics has led to many experiments that may in the future will result in more effective treatment of such diseases as Parkinson’s or Huntington’s. Currently used molecular diagnostics based on DNA analysis can identify 9 neurodegenerative diseases, including spinal cerebellar ataxia inherited in an autosomal dominant manner, dentate-rubro-pallido-luysian atrophy, Friedreich’s disease, ataxia with ocu-lomotorapraxia, Huntington's disease, dystonia type 1, Wilson’s disease, and some cases of Parkinson's disease.

Molecular Effects of L-dopa Therapy in Parkinson's Disease

Parkinson’s disease (PD) is one of the most common neurological diseases in elderly people. The mean age of onset is 55 years of age, and the risk for developing PD increases 5-fold by the age of 70. In PD, there is impairment in both motor and nonmotor (NMS) functions. The strategy of PD motor dysfunction treatment is simple and generally based on the enhancement of dopaminergic transmission by means of the L-dihydroxyphenylalanine (L-dopa) and dopamine (DA) agonists. L-dopa was discovered in the early -60's of the last century by Hornykiewicz and used for the treatment of patients with PD. L-dopa treatment in PD is related to decreased levels of the neurotransmitter (DA) in striatum and ab-sence of DA transporters on the nerve terminals in the brain. L-dopa may also indirectly stimulate the receptors of the D1 and D2 families. Administration of L-dopa to PD patients, especially long-time therapy, may cause side effects in the form of increased toxicity and inflammatory response, as well as disturbances in biothiols metabolism. Therefore, in PD pa-tients treated with L-dopa, monitoring of oxidative stress markers (8-oxo-2’-deoxyguanosine, apoptotic proteins) and in-flammatory factors (high-sensitivity C-reactive protein, soluble intracellular adhesion molecule), as well as biothiol com-pounds (homocysteine, cysteine, glutathione) is recommended. Administration of vitamins B6, B12, and folates along with an effective therapy with antioxidants and/or anti-inflammatory drugs at an early stage of PD might contribute to improvement in the quality of the life of patients with PD and to slowing down or stopping the progression of the disease.

Serum homocysteine levels are decreased in levothyroxine-treated women with autoimmune thyroiditis

BACKGROUND

Hyperhomocysteinemia is a well-known cardiovascular risk factor and its elevation is established in overt hypothyroidism. Since some authors suggest that chronic autoimmune thyroiditis per se may be considered as a novel risk factor of atherosclerosis independent of thyroid function, the analysis of classical cardiovascular risk factors might be helpful in evaluation the causative relationship. Data concerning the impact of thyroid autoimmunity in euthyroid state on homocysteine (Hcy) level is lacking. The aim of this study was to evaluate Hcy level in context of anti-thyroperoxidase antibodies (TPOAbs) in euthyroidism.

METHODS

It is a case-control study. 31 euthyroid women treated with levothyroxine (L-T4) due to Hashimoto thyroiditis (HT) and 26 females in euthyroidism without L-T4 replacement therapy were enrolled in the study. All women with HT had positive TPOAbs. Forty healthy females negative for TPOAbs comparable for age and body mass index (BMI) participated in the study as controls. Exclusion criteria were a history of any acute or chronic disease, use of any medications (including oral contraceptives and vitamin supplements), smoking, alcoholism.

RESULTS

TPOAbs titers were higher in both groups of HT patients versus the healthy controls. Hcy levels were found to be significantly lower in treated HT patients (Me 11 μmol; IQR 4.2 μmol) as compared with healthy controls (Me 13.35 μmol; IQR 6.34 μmol; p = 0.0179). In contrast, no significant difference was found between non treated HT and control group in Hcy level. The study groups and the controls did not differ in age and BMI. Furthermore, levels of TSH, FT4, TC, LDL, HDL and TAG did not differ between the study group and the control group.

CONCLUSION

The main finding of the study is a decrease in Hcy level in treated HT as compared with healthy controls. Based on our observations one can also assume that correct L-T4 replacement was associated here with a decrease of Hcy. Furthermore, it seems that non treated HT in euthyroidism is not associated with Hcy increase, in contrast to overt hypothyroidism. This may be just another argument against the concepts about the role of "euthyroid HT" in the development of atherosclerosis.

Homocysteine Level and Mechanisms of Injury in Parkinson's Disease as Related to MTHFR, MTR, and MTHFD1 Genes Polymorphisms and L-Dopa Treatment

An elevated concentration of total homocysteine (tHcy) in plasma and cerebrospinal fluid is considered to be a risk factor for Alzheimer's disease (AD) and Parkinson's disease (PD). Homocysteine (Hcy) levels are influenced by folate concentrations and numerous genetic factors through the folate cycle, however, their role in the pathogenesis of PD remains controversial. Hcy exerts a neurotoxic action and may participate in the mechanisms of neurodegeneration, such as excitotoxicity, oxidative stress, calcium accumulation, and apoptosis. Elevated Hcy levels can lead to prooxidative activity, most probably through direct interaction with N-methyl-D-aspartate (NMDA) receptors and sensitization of dopaminergic neurons to age-related dysfunction and death. Several studies have shown that higher concentration of Hcy in PD is related to long-term administration of levodopa (L-dopa). An elevation of plasma tHcy levels can also reflect deficiencies of cofactors in remethylation of Hcy to methionine (Met) (folates and vitamin B12) and in its transsulfuration to cysteine (Cys) (vitamin B6). It is believed that the increase in the concentration of Hcy in PD can affect genetic polymorphisms of the folate metabolic pathway genes, such as MTHFR (C677T, A1298C and G1793A), MTR (A2756G), and MTHFD1 (G1958A), whose frequencies tend to increase in PD patients, as well as the reduced concentration of B vitamins. In PD, increased levels of Hcy may lead to dementia, depression and progression of the disease.

Mutations in PRKN and SNCA Genes Important for the Progress of Parkinson's Disease

Although Parkinson’s disease (PD) was first described almost 200 years ago, it remains an incurable disease with a cause that is not fully understood. Nowadays it is known that disturbances in the structure of pathological proteins in PD can be caused by more than environmental and genetic factors. Despite numerous debates and controversies in the literature about the role of mutations in the SNCA and PRKN genes in the pathogenesis of PD, it is evident that these genes play a key role in maintaining dopamine (DA) neuronal homeostasis and that the dysfunction of this homeostasis is relevant to both familial (FPD) and sporadic (SPD) PD with different onset. In recent years, the importance of alphasynuclein (ASN) in the process of neurodegeneration and neuroprotective function of the Parkin is becoming better understood. Moreover, there have been an increasing number of recent reports indicating the importance of the interaction between these proteins and their encoding genes. Among others interactions, it is suggested that even heterozygous substitution in the PRKN gene in the presence of the variants +2/+2 or +2/+3 of NACP-Rep1 in the SNCA promoter, may increase the risk of PD manifestation, which is probably due to ineffective elimination of over-expressed ASN by the mutated Parkin protein. Finally, it seems that genetic testing may be an important part of diagnostics in patients with PD and may improve the prognostic process in the course of PD. However, only full knowledge of the mechanism of the interaction between the genes associated with the pathogenesis of PD is likely to help explain the currently unknown pathways of selective damage to dopaminergic neurons in the course of PD.