The nucleus accumbens (NAc) is the most promising target for drug use disorder treatment. Deep brain stimulation (DBS) of NAc is effective for drug use disorder treatment. However, the mechanisms by which DBS produces its therapeutic effects remain enigmatic. Here, we define a behavioral cut-off criterion to distinguish depressive-like behaviors and nondepressive-like behaviors in mice after morphine withdrawal. We identified a basolateral amygdala (BLA) to NAc D1 medium spiny neuron (D1 MSN) pathway that controls depressive-like behaviors after morphine withdrawal. Furthermore, the paraventricular nucleus of thalamus (PVT) to NAc D2 MSN pathway that controls naloxone-induced acute withdrawal symptoms. Optogenetic-induced long-term potentiation with kappa-opioid receptor (KOR) antagonism enhanced BLA to NAc D1 MSN signaling and also altered the excitation/inhibition balance of NAc D2 MSN signaling. We also verified that a new 50 Hz DBS protocol reversed morphine withdrawal-evoked abnormal plasticity in NAc. Importantly, this refined DBS treatment effectively alleviated naloxone-induced withdrawal symptoms and depressive-like behaviors and prevented stress-induced reinstatement. Taken together, the results demonstrated that input- and cell type-specific synaptic plasticity underlies morphine withdrawal, which may lead to novel targets for the treatment of opioid use disorder.
Yongsheng Zhu, Kejia Wang, Tengfei Ma, Yuanyuan Ji, Yin Lou, Xiaoyu Fu, Ye Lu, Yige Liu, Wei Dang, Qian Zhang, Fangyuan Yin, Kena Wang, Bing Yu, Hongbo Zhang, Jianghua Lai, Yunpeng Wang
B cell clonal expansion and cerebrospinal fluid (CSF) oligoclonal IgG bands are established features of the immune response in multiple sclerosis (MS). Clone-specific IgG1 monoclonal recombinant antibodies (rAbs) derived from MS patient CSF plasmablasts bound to conformational proteolipid protein 1 (PLP1) membrane complexes and, when injected into mouse brain with human complement, recapitulated histologic features of MS pathology: oligodendrocyte cell loss, complement deposition, and CD68+ phagocyte infiltration. Conformational PLP1 membrane epitopes were complex and governed by the local cholesterol and glycolipid microenvironment. Antibodies against conformational PLP1 membrane complexes targeted multiple surface epitopes, were enriched within the CSF compartment, and were detected in most MS patients but not in inflammatory and non-inflammatory neurologic controls. CSF PLP1 complex antibodies provide a pathogenic autoantibody biomarker specific for MS.
Gregory P. Owens, Timothy J. Fellin, Adeline Matschulat, Vanessa Salas, Kristin L. Schaller, Katherine S. Given, Alanna M. Ritchie, Andre Navarro, Kevin Blauth, Ethan G. Hughes, Wendy B. Macklin, Jeffrey L. Bennett
Biological aging can be described as accumulative, prolonged metabolic stress, and is the major risk factor for cognitive decline and Alzheimer’s disease (AD). Recently, we identified and described a quinone reductase 2 (QR2) pathway in the brain, in which QR2 acts as a removable memory constraint and metabolic buffer within neurons. QR2 becomes over-expressed with age, and is possibly a novel contributing factor to age-related metabolic stress and cognitive deficit. We found that in human cells, genetic removal of QR2 produces a shift in the proteome opposing that found in AD brains, while simultaneously reducing oxidative stress. We therefore created highly specific QR2 inhibitors (QR2i’s), enabling evaluation of chronic QR2 inhibition as a novel way to reduce biological-age related metabolic stress and cognitive decline. QR2i’s replicated results obtained by genetic removal of QR2 while local QR2i microinjection improved hippocampal and cortical dependent learning in rats and mice. Continuous consumption of QR2i’s in drinking-water improved cognition and reduced pathology in the brains of AD-model mice (5xFAD), with a noticeable between-sex effect on treatment duration. These results demonstrate the importance of QR2 activity- and pathway function in the healthy and neurodegenerative brain, and the great therapeutic potential of QR2i’s as first-in-class drugs.
Nathaniel L. Gould, Gila R. Scherer, Silvia Carvalho, Khriesto Shurrush, Haneen Kayyal, Efrat Edry, Alina Elkobi, Orit David, Maria Foqara, Darshit Thakar, Tommaso Pavesi, Vijendra Sharma, Matthew Walker, Matthew Maitland, Orly Dym, Shira Albeck, Yoav Peleg, Nicolas Germain, Ilana Babaev, Haleli Sharir, Maya Lalzar, Boris Shklyar, Neta Hazut, Mohammad Khamaisy, Maxime Lévesque, Gilles Lajoie, Massimo Avoli, Gabriel Amitai, Bruce Lefker, Chakrapani Subramanyam, Brian Shilton, Haim Barr, Kobi Rosenblum
Glial activation and inflammation coincide with neurofibrillary tangles (NFT) formation in neurons. However, the mechanism behind tau fibril and glia interaction is poorly understood. Here, we found that tau preformed fibrils (PFF) caused induction of inflammation in microglia by specifically activating the TLR2-MyD88, but not TLR4-MyD88, pathway. Accordingly, TLR2 interacting domain of MyD88 (wtTIDM) peptide inhibited tau PFF-induced activation of TLR2-MyD88-NF-κB pathway resulting in reduced inflammation. Nasal administration of wtTIDM in P301S tau-expressing PS19 mice was found to inhibit gliosis and inflammatory markers, along with reduction of pathogenic tau in the hippocampus, resulting in improved cognitive behavior in PS19 mice. The inhibitory effect of wtTIDM on tau pathology was absent in PS19 mice lacking TLR2, reinforcing the essential involvement of TLR2 in wtTIDM- mediated effects in vivo. While understanding the mechanism further, we found that tau promoter harboured a potential NF-κB binding site and that proinflammatory molecules increased the transcription of tau in neurons via NF-κB. These results suggest that tau-induced neuroinflammation and neuropathology require TLR2 and that neuroinflammation directly upregulates tau in neurons via NF-κB, highlighting a direct connection between inflammation and tauopathy.
Debashis Dutta, Malabendu Jana, Ramesh Kumar Paidi, Moumita Majumder, Sumita Raha, Sridevi Dasarathy, Kalipada Pahan
Protease activated receptor (PAR) 4 (gene: F2RL3) harbors a functional dimorphism, rs773902 A/G (encoding Thr120/Ala120, respectively) and is associated with greater platelet aggregation. The A allele frequency is more common in Black individuals, and Black individuals have a higher incidence of ischemic stroke than White individuals. However, it is not recognized whether the A allele is responsible for worse stroke outcomes. To directly test the in vivo effect of this variant on stroke, we generated mice where F2rl3 was replaced by F2RL3, thereby expressing human PAR4 (hPAR4) with either Thr120 or Ala120. Compared to hPAR4 Ala120 mice, hPAR4 Thr120 mice had worse stroke outcomes, mediated in part by enhanced platelet activation and platelet-neutrophil interactions. Analyses of 7620 Black subjects with 487 incident ischemic strokes demonstrated the AA genotype was a risk for incident ischemic stroke and worse functional outcomes. In humanized mice, ticagrelor with or without aspirin improved stroke outcomes in hPAR4 Ala120 mice, but not in hPAR4 Thr120 mice. P-selectin blockade improved stroke outcomes and reduced platelet-neutrophil interactions in hPAR4 Thr120 mice. Our results may explain some of the racial disparity in stroke and support the need for studies of non-standard anti-platelet therapies for patients expressing PAR4 Thr120.
Frederik Denorme, Nicole D. Armstrong, Michelle L. Stoller, Irina Portier, Emilia A. Tugolukova, Rikki M. Tanner, Emilie Montenont, Seema Bhatlekar, Mark Cody, John L. Rustad, Abigail Ajanel, Neal D. Tolley, Darian C. Murray, Julie L. Boyle, Marvin T. Nieman, Steven E. McKenzie, Christian Con Yost, Leslie A. Lange, Mary Cushman, Marguerite R. Irvin, Paul F. Bray, Robert A. Campbell
The Rad50 interacting protein 1 (Rint1) is a key player in vesicular trafficking between the ER and Golgi apparatus. Biallelic variants in RINT1 cause infantile-onset episodic acute liver failure (ALF). Here, we describe 3 individuals from 2 unrelated families with novel biallelic RINT1 loss-of-function variants who presented with early onset spastic paraplegia, ataxia, optic nerve hypoplasia, and dysmorphic features, broadening the previously described phenotype. Our functional and lipidomic analyses provided evidence that pathogenic RINT1 variants induce defective lipid–droplet biogenesis and profound lipid abnormalities in fibroblasts and plasma that impact both neutral lipid and phospholipid metabolism, including decreased triglycerides and diglycerides, phosphatidylcholine/phosphatidylserine ratios, and inhibited Lands cycle. Further, RINT1 mutations induced intracellular ROS production and reduced ATP synthesis, affecting mitochondria with membrane depolarization, aberrant cristae ultrastructure, and increased fission. Altogether, our results highlighted the pivotal role of RINT1 in lipid metabolism and mitochondria function, with a profound effect in central nervous system development.
Nathalie Launay, Montserrat Ruiz, Laura Planas-Serra, Edgard Verdura, Agustí Rodríguez-Palmero, Agatha Schlüter, Leire Goicoechea, Cristina Guilera, Josefina Casas, Felix Campelo, Emmanuelle Jouanguy, Jean-Laurent Casanova, Odile Boespflug-Tanguy, Maria Vazquez Cancela, Luis González Gutiérrez-Solana, Carlos Casasnovas, Estela Area-Gomez, Aurora Pujol
Mutations in HNRNPH2 cause an X-linked neurodevelopmental disorder with features that include developmental delay, motor function deficits, and seizures. More than 90% of patients with hnRNPH2 have a missense mutation within or adjacent to the nuclear localization signal (NLS) of hnRNPH2. Here, we report that hnRNPH2 NLS mutations caused reduced interaction with the nuclear transport receptor Kapβ2 and resulted in modest cytoplasmic accumulation of hnRNPH2. We generated 2 knockin mouse models with human-equivalent mutations in Hnrnph2 as well as Hnrnph2-KO mice. Knockin mice recapitulated clinical features of the human disorder, including reduced survival in male mice, impaired motor and cognitive functions, and increased susceptibility to audiogenic seizures. In contrast, 2 independent lines of Hnrnph2-KO mice showed no detectable phenotypes. Notably, KO mice had upregulated expression of Hnrnph1, a paralog of Hnrnph2, whereas knockin mice failed to upregulate Hnrnph1. Thus, genetic compensation by Hnrnph1 may counteract the loss of hnRNPH2. These findings suggest that HNRNPH2-related disorder may be driven by a toxic gain of function or a complex loss of HNRNPH2 function with impaired compensation by HNRNPH1. The knockin mice described here are an important resource for preclinical studies to assess the therapeutic benefit of gene replacement or knockdown of mutant hnRNPH2.
Ane Korff, Xiaojing Yang, Kevin O’Donovan, Abner Gonzalez, Brett J.W. Teubner, Haruko Nakamura, James Messing, Fen Yang, Alexandre F. Carisey, Yong-Dong Wang, Tushar Patni, Heather Sheppard, Stanislav S. Zakharenko, Yuh Min Chook, J. Paul Taylor, Hong Joo Kim
Protein aggregation is a hallmark of many neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS). Although mutations in TARDBP, encoding TDP-43, account for less than 1% of all ALS cases, TDP-43-positive aggregates are present in nearly all ALS patients, including patients with sporadic ALS (sALS) or carrying other familial ALS (fALS)-causing mutations. Interestingly, TDP-43 inclusions are also present in subsets of patients with frontotemporal dementia, Alzheimer’s disease, and Parkinson’s disease; therefore, methods of activating intracellular protein quality control machinery capable of clearing toxic cytoplasmic TDP-43 species may alleviate disease-related phenotypes. Here, we identify a novel function of Nemo-like kinase (Nlk) as a negative regulator of lysosome biogenesis. Genetic or pharmacological reduction of Nlk increased lysosome formation and improved clearance of aggregated TDP-43. Furthermore, Nlk reduction ameliorated pathological, behavioral, and lifespan deficits in two distinct mouse models of TDP-43 proteinopathy. Because many toxic proteins can be cleared along the autophagy-lysosome axis, targeted reduction of Nlk represents a potential approach to therapy development for multiple neurodegenerative disorders.
Leon Tejwani, Youngseob Jung, Hiroshi Kokubu, Sowmithra Sowmithra, Luhan Ni, Changwoo Lee, Benjamin Sanders, Paul J. Lee, Yangfei Xiang, Kimberly Luttik, Armand Soriano, Jennifer Yoon, Junhyun Park, Hannah H. Ro, Hyoungseok Ju, Clara Liao, Sofia Massaro Tieze, Frank Rigo, Paymaan Jafar-Nejad, Janghoo Lim
Microglia are the major cell type expressing complement C3a receptor (C3aR) in the brain. Using a knockin mouse line in which a Td-tomato reporter is incorporated into the endogenous C3ar1 locus, we identified 2 major subpopulations of microglia with differential C3aR expression. Expressing the Td-tomato reporter on the APPNL-G-F–knockin (APP-KI) background revealed a significant shift of microglia to a high-C3aR-expressing subpopulation and they were enriched around amyloid β (Aβ) plaques. Transcriptomic analysis of C3aR-positive microglia documented dysfunctional metabolic signatures, including upregulation of hypoxia-inducible factor 1 (HIF-1) signaling and abnormal lipid metabolism in APP-KI mice compared with wild-type controls. Using primary microglial cultures, we found that C3ar1-null microglia had lower HIF-1α expression and were resistant to hypoxia mimetic–induced metabolic changes and lipid droplet accumulation. These were associated with improved receptor recycling and Aβ phagocytosis. Crossing C3ar1-knockout mice with the APP-KI mice showed that C3aR ablation rescued the dysregulated lipid profiles and improved microglial phagocytic and clustering abilities. These were associated with ameliorated Aβ pathology and restored synaptic and cognitive function. Our studies identify a heightened C3aR/HIF-1α signaling axis that influences microglial metabolic and lipid homeostasis in Alzheimer disease, suggesting that targeting this pathway may offer therapeutic benefit.
Manasee Gedam, Michele M. Comerota, Nicholas E. Propson, Tao Chen, Feng Jin, Meng C. Wang, Hui Zheng
Alzheimer’s disease (AD) is the most common cause of dementia. The APOE-ε4 allele of the apolipoprotein E (APOE) gene is the strongest genetic risk factor for late-onset AD. APOE genotype modulates the effect of sleep disruption on AD risk, suggesting a possible link between apoE and sleep in AD pathogenesis which is relatively unexplored. We hypothesized that apoE modifies Aβ deposition and Aβ plaque-associated tau seeding and spreading in the form of neuritic plaque (NP)-tau pathology in response to chronic sleep deprivation (SD) in an apoE isoform-dependent fashion. To test this hypothesis, we used APPPS1 mice expressing human APOE-ε3 or -ε4 with or without AD-tau injection. We found that SD in APPPS1 mice significantly increased Aβ deposition and peri-plaque NP-tau pathology in the presence of APOE4, but not APOE3. SD in APPPS1 mice significantly decreased microglial clustering around plaques and aquaporin-4 (AQP4) polarization around blood vessels in the presence of APOE4 but not APOE3. We also found that sleep deprived APPPS1:E4 mice injected with AD tau had significantly altered sleep behaviors as compared to APPPS1:E3 mice. These findings suggest that APOE-ε4 genotype is a critical modifier in the development of AD pathology in response to SD.
Chanung Wang, Aishwarya Nambiar, Michael R. Strickland, Choonghee Lee, Samira Parhizkar, Alec C. Moore, Erik S. Musiek, Jason D. Ulrich, David M. Holtzman