Differential roles of trithorax protein MLL-1 in regulating neuronal Ion channels

Repressive regulation of potassium channel genes by Polycomb group (PcG) proteins contributes to PcG protein-mediated neuroprotection against neuronal ischemic injury, as seen in an ischemic stroke. Here we asked the question whether Trithorax group (TrxG) proteins, the antagonistic partners of PcG proteins (i.e, epigenetic activators targeting the same genes) may also regulate potassium channels. Results of patch-clamp studies on cultured neuronal cells showed that inhibition of TrxG protein MLL-1 led to an increase in potassium channel activity, an unexpected effect for a presumed gene activator. In contrast, decreased sodium currents were observed with MLL-1 inhibition. Increased or decreased levels of potassium channel protein Kv2.1 or sodium channel protein Nav1.2, respectively, were seen with MLL-1 inhibition, as determined by immunocytochemistry. These results, for the first time, demonstrate an involvement of TrxG protein MLL-1 in regulating neuronal ion channels, potentially repressing potassium channel genes.

Multimodal treatment strategies in Huntington’s disease

Huntington’s disease (HD) is an incurable neurodegenerative disease that causes involuntary movements, emotional lability, and cognitive dysfunction. HD symptoms usually develop between ages 30 and 50, but can appear as early as 2 or as late as 80 years. Currently no neuroprotective and neurorestorative interventions are available. Early multimodal intervention in HD is only possible if the genetic diagnosis is made early. Early intervention in HD is only possible if genetic diagnosis is made at the disease onset or when mild symptoms manifest. Growing evidence and understanding of HD pathomechanism has led researchers to new therapeutic targets. Here, in this article we will talk about the multimodal treatment strategies and recent advances made in this field which can be used to target the HD pathogenesis at its most proximal level.

Facial-onset sensory-motor neuronopathy, a rare variant of Huntington’s disease or chance association?

Objectives: To describe a patient with facial-onset sensory-motor neuronopathy (FOSMN) that later developed Huntington’s disease (HD). Case report: A 62-year-old woman complained of progressive dysphagia 8 years before referral. At initial evaluation, there was excessive salivation, dysphagia, and sensory-motor trigeminal impairment. Denervation was noted on the upper limbs and the tongue. Blink reflexes were abolished. Genetic study of amyotrophic lateral sclerosis (ALS)-related genes was normal. She was diagnosed with FOSMN syndrome. Her clinical state progressively worsened with corneal anesthesia, severe denutrition, right arm and axial weakness. Seven years after referral, she was unable walk and developed generalized chorea. Abnormal huntingtin gene repeat expansion confirmed the diagnosis of HD. She died 16 years after onset of dysphagia. Conclusion: Cases with both HD and ALS have already been reported but not FOSMN and HD, to our knowledge. Some FOSMN cases have been linked to ALS-related gene mutations and HD phenocopies have been associated with C9ORF72 repeat expansions. Recently, huntingtin repeat expansions were described in the ALS population. Although a chance association cannot be excluded, data from the literature are in favor of a pathogenic relationship between FOSMN and HD in this particular case. We suggest that huntingtin gene be more systematically studied in patients with FOSMN.

Role of neuron specific enolase as a biomarker in Parkinson’s disease

Parkinson’s disease (PD) is thought to be the most common neurodegenerative disease with movement disorder. The key motor symptoms are rigidity, tremor, akinesis/hypokinesia/bradykinesia, and postural instability. However, in our day-to-day clinical practice we tend to see several other symptoms which may be motor or non-motor. Non-motor symptoms (NMS) are quite common and debilitating. The pathological hallmarks of PD are loss of dopaminergic neurons in the substantia nigra pars compacta (SNPc) and accumulation of unfolded or misfolded alpha-synuclein. Diagnosis of PD is difficult in the pre-motor stage. Late diagnosis renders a substantial loss of dopaminergic neurons in SNPc and spread of disease in other parts of the brain. This may manifest as either full blown symptoms requiring multiple medications or may even lead to life threatening condition due to lack of early diagnostic tools and techniques. Biomarkers are required to diagnose PD at a very early stage when prevention is possible. Hence, we see a lot of interest among researchers involved in finding a biomarker specific to the disease. Biomarkers may be clinical, image based, genetic, and biochemical. Cerebrospinal fluid (CSF) and serum markers which may correlate with disease pathophysiology are of great significance. One such molecule which recently gained a lot of attention is neuron-specific enolase (NSE). The main aim of this paper is to highlight the role of NSE in predicting neurodegeneration and neuroinflammation ultimately reflecting damage of brain cells in PD.

Endocannabinoidome and its role in neurological disorders-A comprehensive update of existing literature

Mitochondrial and lysosomal dysfunction accounts for a large group of inherited metabolic disorders most of which are due to a dysfunctional mitochondrial respiratory chain (MRC) leading to deficient energy production and defects in phagocytosis in endosomal-lysosomal pathway respectively. MRC function depends on the coordinated expression of both nuclear (nDNA) and mitochondrial (mtDNA) genomes. Thus, mitochondrial diseases can be caused by genetic defects in either the mitochondrial or the nuclear genome, or in the cross-talk between the two. The mitochondrial DNA depletion syndromes (MDSs) are a clinically heterogeneous group of disorders with an autosomal recessive pattern of inheritance that have onset in infancy or early childhood and are characterized by a reduced number of copies of mtDNA in affected tissues and organs. In this review article, we summarized the spectrum of mtDNA depletion disorders along with minor learning of lysosomal storage diseases. This current article offers a perspective on the role of genetics in medical practice and how this role may evolve over the next several years.

Endocannabinoidome and its role in neurological disorders-A comprehensive update of existing literature

Medical benefits of cannabis and related compounds is widely known. Discovery of psychotropic plant cannabinoid Δ9-tetrahydrocannabinol have urged researchers to study more about the cannabinoid system and related therapeutics in the field of neurology and medicine. Where activation of cannabinoid receptor type 1 (CB1R) yielded in unwanted and serious side effects, discovery of cannabinoid receptor type 2 (CB2R) and its ligands gave a new hope. Till now there is limited success in this field because of complex expanded endocannabinoid system comprising of receptors, ligands and enzymes. In this review we will update about the role of endocannabinoidome relevant to neurological disorders.

Factors associated with mortality after decompressive craniectomy in large basal ganglia bleeds

Aim: To assess the efficacy of decompressive craniectomy in patients with large basal ganglia (BG) bleed. To establish predictive criteria of mortality after surgery in patients with BG bleed. Materials: This prospective study includes all patients of large spontaneous BG bleed operated by decompressive craniectomy without hematoma evacuation from October 2012 to September 2015. Data was collected on patient age, gender, distribution of bleed, affected hemisphere dominancy, preexisting medical conditions, admission Glasgow Coma Score (GCS), midline shift on CT or MRI Brain, hematoma volume and anisocoria, duration (hours) between the onset of stroke and operation, post-operative complications, and the duration of hospital stay. This data was correlated with one month mortality of the patients. Results: Total number of patients were 27. Mean age was 51 years and mean GCS was 7.55(range 5-11). The mean volume of the bleed was 68.51 ml. Mortality was noted in 17 out of 27 patients (63%) in 30 days. Thirteen of the 16 patients with intraventricular extension of BG bleed had mortality. The factors that showed statistically significant correlation with one month mortality were age, GCS at admission, volume of the bleed and the intraventricular extension. Conclusion: Large BG bleed was associated with high mortality and morbidity. Age of 50 years or more and GCS ≤ 8 at presentation were poor prognostic factors for decompressive craniectomy in patients with BG bleed. Patients with large BG bleed of volume > 60 ml and intraventricular extension had poor prognosis.