Neurosciences
Abstract
BACKGROUND. Major depressive disorder (MDD) can benefit from novel interventions and personalization. Deep transcranial magnetic stimulation (Deep TMS) targeting the lateral prefrontal cortex (LPFC) using the H1 Coil, was FDA-cleared for treatment of MDD, however recent preliminary data indicate that targeting medial prefrontal cortex (MPFC) using the H7 Coil might induce as good or even better outcomes. Here we explored whether Deep TMS targeting the MPFC is non-inferior to targeting LPFC, and whether electrophysiological or clinical markers for patient selection can be identified. METHODS. The present prospective multicenter randomized study enrolled 169 MDD patients who failed antidepressant treatments in the current episode. Patients were randomized to receive 24 Deep TMS sessions over 6 weeks, using either the H1 Coil or the H7 Coil. The primary efficacy endpoint was the change from baseline to week 6 in the Hamilton-Depression-Rating-Scores. RESULTS. Clinical efficacy and safety profiles were similar and not significantly different between groups, with response rates of 60.9% for the H1 Coil and 64.2% for the H7 Coil. Moreover, brain activity measured by EEG during the first treatment session correlated with clinical outcomes in a coil-specific manner, and a cluster of baseline clinical symptoms was found to potentially distinguish between patients who can benefit from each Deep TMS target. CONCLUSION. This study provides a new treatment option for MDD, using the H7 Coil, and initial guidance to differentiate between patients likely to respond to LPFC versus MPFC stimulation targets, which require further validation studies. TRIAL REGISTRATION. ClinicalTrials.gov NCT03012724. FUNDING. Brainsway Ltd.
Authors
Abraham Zangen, Samuel Zibman, Aron Tendler, Noam Barnea-Ygael, Uri Alyagon, Daniel M. Blumberger, Geoffrey Grammer, Hadar Shalev, Tatiana Gulevsky, Tanya Vapnik, Alexander Bystritsky, Igor Filipčić, David Feifel, Ahava Stein, Frederic Deutsch, Yiftach Roth, Mark S. George
Abstract
Neuromyelitis optica spectrum disorders (NMOSD) are inflammatory autoimmune disorders of the CNS. Immunoglobulin G autoantibodies targeting the aquaporin-4 water channel (AQP4-IgG) are the pathogenic effector of NMOSD. Dysregulated T follicular helper (Tfh) cells have been implicated in the loss of B-cell tolerance in autoimmune diseases. The contribution of Tfh cells to disease activity and the therapeutic potential of targeting these cells in NMOSD remain unclear. Here, we established an autoimmune model of NMOSD by immunizing mice against AQP4 via in vivo electroporation. After AQP4 immunization, mice displayed AQP4 autoantibodies in the blood circulation, blood-brain barrier disruption, and IgG infiltration in the spinal cord parenchyma. Moreover, AQP4 immunization induced motor impairments and NMOSD-like pathologies including astrocytopathy, demyelination, axonal loss, and microglia activation. These were associated with increased splenic Tfh, T helper 1 (Th1) and T helper 17 (Th17) cells, memory B cells and plasma cell. AQP4-deficient mice did not displayed motor impairments and NMOSD-like pathologies after AQP4 immunization. Importantly, abrogating inducible costimulator (ICOS)/inducible costimulator ligand (ICOS-L) signalling using anti-ICOS-L antibody depleted Tfh cells and suppressed the response of Th1 and Th17 cells, memory B cells, and plasma cells in AQP4-immunized mice. These findings were associated with ameliorated motor impairments and spinal cord pathologies. This study suggests a role of Tfh cells in the pathophysiology of NMOSD in a novel mouse model with AQP4 autoimmunity. It also provides an animal model for further investigating the immunological mechanisms underlying AQP4 autoimmunity, and for developing novel therapeutic interventions targeting the autoimmune reactions in NMOSD.
Authors
Leung-Wah Yick, Oscar Ka-Fai Ma, Ethel Yin-Ying Chan, Krystal Xiwing Yau, Jason Shing-Cheong Kwan, Koon-Ho Chan
Abstract
The molecular mediators of cell death and inflammation in Alzheimer’s disease (AD) have yet to be fully elucidated. Caspase-8 is a critical regulator of several cell death and inflammatory pathways; however, its role in AD pathogenesis has not yet been examined in detail. In the absence of Caspase-8, mice are embryonic lethal due to excessive RIPK3-dependent necroptosis. Compound RIPK3 and Caspase-8 mutants rescue embryonic lethality, which we leveraged to examine the roles of these pathways in an amyloid beta (Aβ)-mediated mouse model of AD. We find that combined deletion of Caspase-8 and RIPK3, but not RIPK3 alone, leads to diminished Aβ deposition and microgliosis in the 5xFAD mouse model of AD. Despite its well-known role in cell death, Caspase-8 does not appear to impact cell loss in the 5xFAD model. In contrast, we found that Caspase-8 is a critical regulator of Aβ-driven inflammasome gene expression and IL-1β release. Interestingly, loss of RIPK3 had only a modest effect on disease progression suggesting that inhibition of necroptosis or RIPK3-mediated cytokine pathways are not critical during mid stages of Aβ amyloidosis. These findings suggest that therapeutics targeting Caspase-8 may represent a novel strategy to limit Aꞵ amyloidosis and neuroinflammation in AD.
Authors
Sushanth Kumar, Sakar Budhathoki, Christopher B. Oliveira, August D. Kahle, O. Yipkin Calhan, John R. Lukens, Christopher D. Deppmann
Abstract
Pathogenic SOX2 variants typically cause severe ocular defects within a SOX2-disorder spectrum that includes hypogonadotropic hypogonadism (HH). We examined exome sequencing data from a large, well-phenotyped cohort of patients (n=1453) with Idiopathic Hypogonadotropic Hypogonadism (IHH) for pathogenic SOX2 variants to investigate the underlying pathogenic SOX2 spectrum and its associated phenotypes. We identified eight IHH individuals harboring heterozygous pathogenic SOX2 variants with variable ocular phenotypes. These variant proteins were tested in vitro to determine whether a causal relationship between IHH and SOX2 exists. We found that Sox2 is highly expressed in the hypothalamus of adult mice and colocalizes with KISS1 expression in the anteroventral periventricular nucleus of adult female mice. In vitro, shRNA suppression of mouse SOX2 protein in Kiss-expressing cell lines increases the levels of human kisspeptin luciferase transcription (hKISS-luc), while SOX2 overexpression represses hKiss-luc transcription. Further, four of the identified SOX2 variants prevented this SOX2-mediated repression of hKiss-luc. Together these data suggest that pathogenic SOX2 variants contribute to both anosmic and normosmic forms of IHH attesting to hypothalamic defects in the SOX2-disorder spectrum. Our study describes novel mechanisms contributing to SOX2-related disease and highlights the necessity of SOX2 screening in IHH genetic evaluation irrespective of associated ocular defects.
Authors
Jessica Cassin, Maria I. Stamou, Kimberly W. Keefe, Kaitlin Sung, Celine Bojo, Karen J. Tonsfeldt, Rebecca A. Rojas, Vanessa Ferreira Lopes, Lacey Plummer, Kathryn B. Salnikov, David L. Keefe Jr., Metin Ozata, Myron Genel, Neoklis A. Georgopoulos, Janet E. Hall, William F. Crowley Jr., Stephanie B. Seminara, Pamela L. Mellon, Ravikumar Balasubramanian
Abstract
It is suggested that activation of receptor for advanced glycation end products (RAGE) induces proinflammatory response in diabetic nerve tissues. Macrophage infiltration is invoked in the pathogenesis of diabetic polyneuropathy (DPN), while the association between macrophage and RAGE activation and the downstream effects of macrophages remain to be fully clarified in DPN. This study explored the role of RAGE in the pathogenesis of DPN through the modified macrophages. Infiltrating proinflammatory macrophages impaired insulin sensitivity, atrophied the neurons in dorsal root ganglion, and slowed retrograde axonal transport (RAT) in the sciatic nerve of type 1 diabetic mice. RAGE-null mice showed an increase in the population of antiinflammatory macrophages, accompanied by intact insulin sensitivity, normalized ganglion cells, and RAT. BM transplantation from RAGE-null mice to diabetic mice protected the peripheral nerve deficits, suggesting that RAGE is a major determinant for the polarity of macrophages in DPN. In vitro coculture analyses revealed proinflammatory macrophage–elicited insulin resistance in the primary neuronal cells isolated from dorsal root ganglia. Applying time-lapse recording disclosed a direct impact of proinflammatory macrophage and insulin resistance on the RAT deficits in primary neuronal cultures. These results provide a potentially novel insight into the development of RAGE-related DPN.
Authors
Sho Osonoi, Hiroki Mizukami, Yuki Takeuchi, Hikari Sugawa, Saori Ogasawara, Shizuka Takaku, Takanori Sasaki, Kazuhiro Kudoh, Koichi Ito, Kazunori Sango, Ryoji Nagai, Yasuhiko Yamamoto, Makoto Daimon, Hiroshi Yamamoto, Soroku Yagihashi
Abstract
SMA with respiratory distress type 1 (SMARD1) and Charcot Marie Tooth type 2S (CMT2S) are a result of mutations in immunoglobulin mu DNA binding protein 2 (IGHMBP2). IGHMBP2 is an UPF1-like helicase with proposed roles in several cellular processes including translation. This study examines activator of basal transcription (ABT1), a modifier of the FVB-Ighmbp2nmd/nmd phenotype. Microscale thermophoresis and dynamic light scattering demonstrate IGHMBP2 and ABT1 proteins directly interact with high affinity. The association of ABT1 with IGHMBP2 significantly increases the ATPase and helicase activity as well as the processivity of IGHMBP2. The IGHMBP2-ABT1 complex interacts with the 5' external transcribed spacer and U3 snoRNA suggesting that the IGHMBP2-ABT1 complex is important for pre-rRNA processing. Intracerebroventricular injection of scAAV9-Abt1 decreases FVB-Ighmbp2nmd/nmd disease pathology, significantly increases lifespan and substantially decreases neuromuscular junction denervation. ABT1 is the first disease modifying gene identified for SMARD1. We provide a mechanism that proposes ABT1 decreases disease pathology in FVB-Ighmbp2nmd/nmd mutants by optimizing IGHMBP2 biochemical activity (ATPase and helicase activity). Our studies provide important insight into SMARD1 pathogenesis suggesting ABT1 modifies IGHMBP2 activity as a means to regulate pre-rRNA processing.
Authors
Gangadhar P. Vadla, Sara M. Ricardez Hernandez, Jiude Mao, Mona O. Garro-Kacher, Zachary C. Lorson, Ronin P. Rice, Sarah A. Hansen, Christian L. Lorson, Kamal Singh, Monique A. Lorson
Abstract
Dopamine acts on neurons in the arcuate nucleus (ARC) of the hypothalamus, which controls homeostatic feeding responses. Here we demonstrate a differential enrichment of dopamine receptor 1 (Drd1) expression in food intake–promoting agouti related peptide (AgRP)/neuropeptide Y (NPY) neurons and a large proportion of Drd2-expressing anorexigenic proopiomelanocortin (POMC) neurons. Owing to the nature of these receptors, this translates into a predominant activation of AgRP/NPY neurons upon dopamine stimulation and a larger proportion of dopamine-inhibited POMC neurons. Employing intersectional targeting of Drd2-expressing POMC neurons, we reveal that dopamine-mediated POMC neuron inhibition is Drd2 dependent and that POMCDrd2+ neurons exhibit differential expression of neuropeptide signaling mediators compared with the global POMC neuron population, which manifests in enhanced somatostatin responsiveness of POMCDrd2+ neurons. Selective chemogenetic activation of POMCDrd2+ neurons uncovered their ability to acutely suppress feeding and to preserve body temperature in fasted mice. Collectively, the present study provides the molecular and functional characterization of POMCDrd2+ neurons and aids our understanding of dopamine-dependent control of homeostatic energy-regulatory neurocircuits.
Authors
Isabella Gaziano, Svenja Corneliussen, Nasim Biglari, René Neuhaus, Linyan Shen, Tamara Sotelo-Hitschfeld, Paul Klemm, Lukas Steuernagel, Alain J. De Solis, Weiyi Chen, F. Thomas Wunderlich, Peter Kloppenburg, Jens C. Brüning
Abstract
Antisense oligonucleotides (ASOs) have emerged as one of the most innovative new genetic drug modalities. However, their high molecular weight limits their bioavailability for otherwise treatable neurological disorders. We investigated conjugation of ASOs to an antibody against the murine transferrin receptor (TfR), 8D3130, and evaluated it via systemic administration in mouse models of the neurodegenerative disease, spinal muscular atrophy (SMA). SMA, like several other neurological and neuromuscular diseases, is treatable with single-stranded ASOs that modulate splicing of the survival motor neuron 2 (SMN2) gene. Administration of 8D3130-ASO conjugate resulted in elevated levels of bioavailability to the brain. Additionally, 8D3130-ASO yielded therapeutic levels of SMN2 splicing in the central nervous system of adult hSMN2 transgenic mice which resulted in extended survival of a severely affected SMA mouse model. Systemic delivery of nucleic acid therapies with brain targeting antibodies offers powerful translational potential for future treatments of neuromuscular and neurodegenerative diseases.
Authors
Suzan M. Hammond, Frank Abendroth, Larissa Goli, Jessica Stoodley, Matthew Burrell, George Thom, Ian Gurrell, Nina Ahlskog, Michael J. Gait, Matthew J.A. Wood, Carl I. Webster
Abstract
The folding and trafficking of transmembrane glycoproteins are essential for cellular homeostasis and compromised in many diseases. In Niemann-Pick type C disease, a lysosomal disorder characterized by impaired intracellular cholesterol trafficking, the transmembrane glycoprotein NPC1 misfolds due to disease-causing missense mutations. While mutant NPC1 has emerged as a robust target for proteostasis modulators, these drug development efforts have been unsuccessful in mouse models. Here, we demonstrate unexpected differences in trafficking through the medial Golgi between mouse and human I1061T-NPC1, a common disease-causing mutant. We establish that these distinctions are governed by differences in the NPC1 protein sequence rather than by variations in the ER folding environment. Moreover, we demonstrate direct effects of mutant protein trafficking on the response to small molecules that modulate the endoplasmic reticulum folding environment by affecting Ca++ concentration. Finally, we develop a panel of isogenic human NPC1 iNeurons expressing wild type, I1061T-, and R934L-NPC1 and demonstrate their utility in testing these candidate therapeutics. Our findings identify important rules governing mutant NPC1’s response to proteostatic modulators and highlight the importance of species- and mutation-specific responses for therapy development.
Authors
Mark L. Schultz, Kylie J. Schache, Ruth D. Azaria, Esmée Q. Kuiper, Steven Erwood, Evgueni A. Ivakine, Nicole Y. Farhat, Forbes D. Porter, Koralege C. Pathmasiri, Stephanie M. Cologna, Michael D. Uhler, Andrew P. Lieberman
Abstract
Recessive PJVK mutations that cause a deficiency of pejvakin, a protein expressed in both sensory hair cells and first-order neurons of the inner ear, are an important cause of hereditary hearing impairment. Patients with PJVK mutations garner limited benefits from cochlear implantation; thus, alternative biological therapies may be required to address this clinical difficulty. The synthetic adeno-associated viral vector Anc80L65, with its wide tropism and high transduction efficiency in various inner ear cells, may provide a solution. We delivered the PJVK transgene to the inner ear of Pjvk mutant mice using the synthetic Anc80L65 vector. We observed robust exogenous pejvakin expression in the hair cells and neurons of the cochlea and vestibular organs. Subsequent morphologic and audiologic studies demonstrated significant restoration of spiral ganglion neuron density and hair cells in the cochlea, along with partial recovery of sensorineural hearing impairment. In addition, we observed a recovery of vestibular ganglion neurons and balance function to WT levels. Our study demonstrates the utility of Anc80L65-mediated gene delivery in Pjvk mutant mice and provides insights into the potential of gene therapy for PJVK-related inner ear deficits.
Authors
Ying-Chang Lu, Yi-Hsiu Tsai, Yen-Huei Chan, Chin-Ju Hu, Chun-Ying Huang, Ru Xiao, Chuan-Jen Hsu, Luk H. Vandenberghe, Chen-Chi Wu, Yen-Fu Cheng
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