Investigation of mitochondrial calcium uniporter role in embryonic and adult motor neurons from G93AhSOD1 mice.

Amyotrophic lateral sclerosis is characterized by progressive death of motor neurons (MNs) with glutamate excitotoxicity and mitochondrial Ca2+ overload as critical mechanisms in disease pathophysiology. We used MNs from G93AhSOD1 and nontransgenic embryonic cultures and adult mice to analyze the expression of the main mitochondrial calcium uniporter (MCU). MCU was overexpressed in cultured embryonic G93AhSOD1 MNs compared to nontransgenic MNs but downregulated in MNs from adult G93AhSOD1 mice. Furthermore, cultured embryonic G93AhSOD1 were rescued from kainate-induced excitotoxicity by the Ca2+/calmodulin-dependent protein kinase type II inhibitor; KN-62, which reduced MCU expression in G93AhSOD1 MNs. MCU activation via kaempferol neither altered MCU expression nor influenced MN survival. However, its acute application served as a fine tool to study spontaneous Ca2+ activity in cultured neurons which was significantly altered by the mutated hSOD1. Pharmacological manipulation of MCU expression might open new possibilities to fight excitotoxic damage in amyotrophic lateral sclerosis.

Delayed Post-hypoxic Leukoencephalopathy (DPHL)-An Uncommon Variant of Hypoxic Brain Damage in Adults.

Delayed post-hypoxic leukoencephalopathy (DPHL) is an uncommon, potentially under-recognized, cause of hypoxia induced white matter injury. It characteristically follows a biphasic course: After an initial phase of altered neurologic status a recovery occurs which is then followed by a recurring phase of neurologic deterioration, typically 2-4 weeks after the initial event. At this time white matter changes can be identified on MRI, which are the hallmark of DPHL. The characteristics and the typical MR-imaging signs of DPHL are discussed in this case report.

Novel Protein Kinase Inhibitors Related to Tau Pathology Modulate Tau Protein-Self Interaction Using a Luciferase Complementation Assay.

The current number of drugs available for the treatment of Alzheimer's disease (AD) is strongly limited and their benefit for therapy is given only in the early state of the disease. An effective therapy should affect those processes which mainly contribute to the neuronal decay. There have been many approaches for a reduction of toxic Aß peptides which mostly failed to halt cognitive deterioration in patients. The formation of neurofibrillary tangles (NFT) and its precursor tau oligomers have been suggested as main cause of neuronal degeneration because of a direct correlation of their density to the degree of dementia. Reducing of tau aggregation may be a viable approach for the treatment of AD. NFT consist of hyperphosphorylated tau protein and tau hyperphosphorylation reduces microtubule binding. Several protein kinases are discussed to be involved in tau hyperphosphorylation. We developed novel inhibitors of three protein kinases (gsk-3ß, cdk5, and cdk1) and discussed their activity in relation to tau phosphorylation and on tau⁻tau interaction as a nucleation stage of a tau aggregation in cells. Strongest effects were observed for those inhibitors with effects on all the three kinases with emphasis on gsk-3ß in nanomolar ranges.

Alleviation of Psychological Distress and the Improvement of Quality of Life in Patients With Amyotrophic Lateral Sclerosis: Adaptation of a Short-Term Psychotherapeutic Intervention.

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that is inevitably fatal. To be diagnosed with a terminal illness such as ALS deeply affects one's personal existence and goes along with significant changes regarding the physical, emotional, and social domains of the patients' life. ALS patients have to face a rapidly debilitating physical decline which restrains mobility and impairs all activities of daily living. This progressive loss of autonomy may lead to a sense of hopelessness and loss of quality of life, which in turn may even result in thoughts about physician-assisted suicide. Here, we would like to propose a psychotherapeutic manualized, individual, semi-structured intervention to relieve distress and promote psychological well-being in ALS patients. This short-term intervention was originally developed for advanced cancer patients. "Managing Cancer and Living Meaningfully (CALM)" focuses on the four dimensions: (i) symptom management and communication with healthcare providers, (ii) changes in self and relations with close others, (iii) spirituality, sense of meaning and purpose and (iv) thinking of the future, hope, and mortality. We suggest to supplement the concept by two additional dimensions which take into account specific issues of ALS patients: (v) communication skills, and (vi) emotional expression and control. This therapeutic concept named "ManagIng Burden in ALS and Living Meaningfully (mi-BALM)" may be a further treatment option to help improving quality of life of ALS patients.

Provision of assistive technology devices among people with ALS in Germany: a platform-case management approach.

OBJECTIVE: The procurement of assistive technology devices (ATD) is an essential component of managed care in ALS. The objective was to analyze the standards of care for ATD and to identify challenges in the provision process. METHODS: A cohort study design was used. We investigated the provision of 11,364 ATD in 1494 patients with ALS at 12 ALS centers in Germany over four years. Participants were patients that entered a case management program for ATD including systematic assessment of ATD on a digital management platform. RESULTS: Wheelchairs (requested in 65% of patients), orthoses (52%), bathroom adaptations (49%), and communication devices (46%) were the most needed ATD. There was a wide range in the number of indicated ATD per patient: 1 to 4 ATD per patient in 45% of patients, 5 to 20 ATD in 48%, and >20 ATD in 7% of patients. Seventy percent of all requested ATD were effectively delivered. However, an alarming failure rate during procurement was found in ATD that are crucial for ALS patients such as powered wheelchairs (52%), communication devices (39%), or orthoses (21%). Leading causes for not providing ATD were the refusal by health insurances, the decision by patients, and the death of the patient before delivery of the device. CONCLUSIONS: The need for ATD was highly prevalent among ALS patients. Failed or protracted provision posed substantial barriers to ATD procurement. Targeted national strategies and the incorporation of ATD indication criteria in international ALS treatment guidelines are urgently needed to overcome these barriers.

TDP-43 self-interaction is modulated by redox-active compounds Auranofin, Chelerythrine and Riluzole.

Amyotrophic lateral sclerosis (ALS) represents a fatal neurodegenerative disease, which is characterized by a rapid loss of lower and upper motor neurons. As a major neuropathological hallmark, protein aggregates containing the Transactivating Response Region (TAR) DNA Binding Protein (TDP-43) are detectable in about 95% of sporadic ALS patients. TDP-43 interacts with itself physiologically to form liquid droplets, which may progress to pathological aggregates. In this study, we established the NanoBit luciferase complementation assay to measure TDP-43 self-interaction and found the fusion of the split luciferase subunits to the N-terminus of the protein as the strongest interacting partners. A screen of pharmacologically active compounds from the LOPAC®1280 library identified auranofin, chelerythrine and riluzole as dose-dependent inhibitors of TDP-43 self-interaction. Further analysis of drug action of the gold-containing thioredoxin reductase inhibitor auranofin revealed a redistribution from insoluble TDP-43 protein pool to PBS-soluble protein pool in N2a cells. In addition, auranofin treatment diminished reduced glutathione as a sign for oxidative modulation.

TDP-43 and Cytoskeletal Proteins in ALS.

Amyotrophic lateral sclerosis (ALS) represents a rapidly progressing neurodegenerative disease and is characterized by a degeneration of motor neurons. Motor neurons are particularly susceptible to selective and early degeneration because of their extended axon length and their dependency on the cytoskeleton for its stability, signaling, and axonal transport. The motor neuron cytoskeleton comprises actin filaments, neurofilaments like peripherin, and microtubules. The Transactivating Response Region (TAR) DNA Binding Protein (TDP-43) forms characteristic cytoplasmic aggregates in motor neurons of ALS patients, and at least in part, the pathogenesis of ALS seems to be driven by toxic pTDP-43 aggregates in cytoplasm, which lead to a diminished axon formation and reduced axon length. Diminished axon formation and reduced axon length suggest an interaction of TDP-43 with the cytoskeleton of motor neurons. TDP-43 interacts with several cytoskeletal components, e.g., the microtubule-associated protein 1B (MAP1B) or the neurofilament light chain (NFL) through direct binding to its RNA. From a clinical perspective, cytoskeletal biomarkers like phosphorylated neurofilament heavy chain (pNFH) and NFL are already clinically used in ALS patients to predict survival, disease progression, and duration. Thus, in this review, we focus on the interaction of TDP-43 with the different cytoskeleton components such as actin filaments, neurofilaments, and microtubules as well as their associated proteins as one aspect in the complex pathogenesis of ALS.

Late onset dHMN II caused by c.404C>G mutation in HSPB1 gene.

Distal hereditary motor neuropathy (dHMN) type II is genetically heterogeneous. We report three siblings of a German family with late onset distal motor neuropathy due to the c.404C>G mutation in heat-shock 27-kDa protein 1 gene (HSPB1/HSP27). A 36-year-old mutation carrier, daughter of one sibling, did not present any clinical or electrophysiological abnormalities. The index patient (oldest brother) developed weakness of the distal lower limbs and nocturnal muscle cramps at the age of 54. After 5 years this patient developed an l-DOPA-responsive hypokinetic rigid syndrome, establishing a diagnosis of Parkinson's disease. Although none of the three other mutation carriers displayed Parkinsonian signs, a pathogenic relationship with Parkinson's disease remains a possibility, based on the known molecular pathology of HSPB1. The rare pathogenic HSPB1 c.404C>G mutation may predispose for late-onset of dHMN type II.

Epigenetic modulation of the drug resistance genes MGMT, ABCB1 and ABCG2 in glioblastoma multiforme.

BACKGROUND: Resistance of the highly aggressive glioblastoma multiforme (GBM) to drug therapy is a major clinical problem resulting in a poor patient's prognosis. Beside promoter methylation of the O6-methylguanine-DNA-methyltransferase (MGMT) gene the efflux transporters ABCB1 and ABCG2 have been suggested as pivotal factors contributing to drug resistance, but the methylation of ABCB1 and ABCG2 has not been assessed before in GBM. METHODS: Therefore, we evaluated the proportion and prognostic significance of promoter methylation of MGMT, ABCB1 and ABCG2 in 64 GBM patient samples using pyrosequencing technology. Further, the single nucleotide polymorphisms MGMT C-56 T (rs16906252), ABCB1 C3435T (rs1045642) and ABCG2 C421A (rs2231142) were determined using the restriction fragment length polymorphism method (RFLP). To study a correlation between promoter methylation and gene expression, we analyzed MGMT, ABCB1 and ABCG2 expression in 20 glioblastoma and 7 non-neoplastic brain samples. RESULTS: Despite a significantly increased MGMT and ABCB1 promoter methylation in GBM tissue, multivariate regression analysis revealed no significant association between overall survival of glioblastoma patients and MGMT or ABCB1 promoter methylation. However, a significant negative correlation between promoter methylation and expression could be identified for MGMT but not for ABCB1 and ABCG2. Furthermore, MGMT promoter methylation was significantly associated with the genotypes of the MGMT C-56 T polymorphism showing a higher methylation level in the T allele bearing GBM. CONCLUSIONS: In summary, the data of this study confirm the previous published relation of MGMT promoter methylation and gene expression, but argue for no pivotal role of MGMT, ABCB1 and ABCG2 promoter methylation in GBM patients' survival.

MEF promotes stemness in the pathogenesis of gliomas.

High-grade gliomas are aggressive and uniformly fatal tumors, composed of a heterogeneous population of cells that include many with stem-cell-like properties. The acquisition of stem-like traits might contribute to glioma initiation, growth, and recurrence. Here we investigated the role of the transcription factor myeloid Elf-1 like factor (MEF, also known as ELF4) in gliomas. We found that MEF is highly expressed in both human and mouse glioblastomas and its absence impairs gliomagenesis in a PDGF-driven glioma mouse model. We show that modulation of MEF levels in both mouse neural stem cells and human glioblastoma cells has a significant impact on neurosphere formation. Moreover, we identify Sox2 as a direct downstream target of MEF. Taken together, our studies implicate MEF as a previously unrecognized gatekeeper gene in gliomagenesis that promotes stem cell characteristics through Sox2 activation.