Wong, FK;Selten, M;Rosés-Novella, C;Sreenivasan, V;Pallas-Bazarra, N;Serafeimidou-Pouliou, E;Hanusz-Godoy, A;Oozeer, F;Edwards, R;Marín, O;
PMID: 35793629 | DOI: 10.1016/j.celrep.2022.111037
One key factor underlying the functional balance of cortical networks is the ratio of excitatory and inhibitory neurons. The mechanisms controlling the ultimate number of interneurons are beginning to be elucidated, but to what extent similar principles govern the survival of the large diversity of cortical inhibitory cells remains to be investigated. Here, we investigate the mechanisms regulating developmental cell death in neurogliaform cells, bipolar cells, and basket cells, the three main populations of interneurons originating from the caudal ganglionic eminence and the preoptic region. We found that all three subclasses of interneurons undergo activity-dependent programmed cell death. However, while neurogliaform cells and basket cells require glutamatergic transmission to survive, the final number of bipolar cells is instead modulated by serotonergic signaling. Together, our results demonstrate that input-specific modulation of neuronal activity controls the survival of cortical interneurons during the critical period of programmed cell death.
Donne, R;Saroul-Ainama, M;Cordier, P;Hammoutene, A;Kabore, C;Stadler, M;Nemazanyy, I;Galy-Fauroux, I;Herrag, M;Riedl, T;Chansel-Da Cruz, M;Caruso, S;Bonnafous, S;Öllinger, R;Rad, R;Unger, K;Tran, A;Couty, JP;Gual, P;Paradis, V;Celton-Morizur, S;Heikenwalder, M;Revy, P;Desdouets, C;
PMID: 35768000 | DOI: 10.1016/j.devcel.2022.06.003
Non-alcoholic steatotic liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. NAFLD has a major effect on the intrinsic proliferative properties of hepatocytes. Here, we investigated the mechanisms underlying the activation of DNA damage response during NAFLD. Proliferating mouse NAFLD hepatocytes harbor replication stress (RS) with an alteration of the replication fork's speed and activation of ATR pathway, which is sufficient to cause DNA breaks. Nucleotide pool imbalance occurring during NAFLD is the key driver of RS. Remarkably, DNA lesions drive cGAS/STING pathway activation, a major component of cells' intrinsic immune response. The translational significance of this study was reiterated by showing that lipid overload in proliferating HepaRG was sufficient to induce RS and nucleotide pool imbalance. Moreover, livers from NAFLD patients displayed nucleotide pathway deregulation and cGAS/STING gene alteration. Altogether, our findings shed light on the mechanisms by which damaged NAFLD hepatocytes might promote disease progression.
Bixler, SL;Stefan, CP;Jay, AN;Rossi, FD;Ricks, KM;Shoemaker, CJ;Moreau, AM;Zeng, X;Hooper, JW;Dyer, DN;Frick, OM;Koehler, JW;Kearney, BJ;DiPinto, N;Liu, J;Tostenson, SD;Clements, TL;Smith, JM;Johnson, JA;Berrier, KL;Esham, HL;Delp, KL;Coyne, SR;Bloomfield, HA;Kuehnert, PA;Akers, K;Gibson, KM;Minogue, TD;Nalca, A;Pitt, MLM;
PMID: 35632755 | DOI: 10.3390/v14051013
The emergence of SARS-CoV-2 and the subsequent pandemic has highlighted the need for animal models that faithfully replicate the salient features of COVID-19 disease in humans. These models are necessary for the rapid selection, testing, and evaluation of potential medical countermeasures. Here, we performed a direct comparison of two distinct routes of SARS-CoV-2 exposure-combined intratracheal/intranasal and small particle aerosol-in two nonhuman primate species, rhesus and cynomolgus macaques. While all four experimental groups displayed very few outward clinical signs, evidence of mild to moderate respiratory disease was present on radiographs and at necropsy. Cynomolgus macaques exposed via the aerosol route also developed the most consistent fever responses and had the most severe respiratory disease and pathology. This study demonstrates that while all four models produced suitable representations of mild COVID-like illness, aerosol exposure of cynomolgus macaques to SARS-CoV-2 produced the most severe disease, which may provide additional clinical endpoints for evaluating therapeutics and vaccines.
Kato, T;Radicioni, G;Papanikolas, MJ;Stoychev, GV;Markovetz, MR;Aoki, K;Porterfield, M;Okuda, K;Barbosa Cardenas, SM;Gilmore, RC;Morrison, CB;Ehre, C;Burns, KA;White, KK;Brennan, TA;Goodell, HP;Thacker, H;Loznev, HT;Forsberg, LJ;Nagase, T;Rubinstein, M;Randell, SH;Tiemeyer, M;Hill, DB;Kesimer, M;O'Neal, WK;Ballard, ST;Freeman, R;Button, B;Boucher, RC;
PMID: 35363522 | DOI: 10.1126/sciadv.abm9718
Cystic fibrosis (CF) is characterized by abnormal transepithelial ion transport. However, a description of CF lung disease pathophysiology unifying superficial epithelial and submucosal gland (SMG) dysfunctions has remained elusive. We hypothesized that biophysical abnormalities associated with CF mucus hyperconcentration provide a unifying mechanism. Studies of the anion secretion-inhibited pig airway model of CF revealed elevated SMG mucus concentrations, osmotic pressures, and SMG mucus accumulation. Human airway studies revealed hyperconcentrated CF SMG mucus with raised osmotic pressures and cohesive forces predicted to limit SMG mucus secretion/release. Using proline-rich protein 4 (PRR4) as a biomarker of SMG secretion, CF sputum proteomics analyses revealed markedly lower PRR4 levels compared to healthy and bronchiectasis controls, consistent with a failure of CF SMGs to secrete mucus onto airway surfaces. Raised mucus osmotic/cohesive forces, reflecting mucus hyperconcentration, provide a unifying mechanism that describes disease-initiating mucus accumulation on airway surfaces and in SMGs of the CF lung.
The Journal of experimental medicine
Snyder, ME;Moghbeli, K;Bondonese, A;Craig, A;Popescu, I;Fan, L;Tabib, T;Lafyatis, R;Chen, K;Trejo Bittar, HE;Lendermon, E;Pilewski, J;Johnson, B;Kilaru, S;Zhang, Y;Sanchez, PG;Alder, JK;Sims, PA;McDyer, JF;
PMID: 35285873 | DOI: 10.1084/jem.20212059
Acute cellular rejection is common after lung transplantation and is associated with an increased risk of early chronic rejection. We present combined single-cell RNA and TCR sequencing on recipient-derived T cells obtained from the bronchoalveolar lavage of three lung transplant recipients with rejection and compare them with T cells obtained from the same patients after treatment of rejection with high-dose systemic glucocorticoids. At the time of rejection, we found an oligoclonal expansion of cytotoxic CD8+ T cells that all persisted as tissue resident memory T cells after successful treatment. Persisting CD8+ allograft-resident T cells have reduced gene expression for cytotoxic mediators after therapy with glucocorticoids but accumulate around airways. This clonal expansion is discordant with circulating T cell clonal expansion at the time of rejection, suggesting in situ expansion. We thus highlight the accumulation of cytotoxic, recipient-derived tissue resident memory T cells within the lung allograft that persist despite the administration of high-dose systemic glucocorticoids. The long-term clinical consequences of this persistence have yet to be characterized.
Liu, H;Wang, X;
PMID: 35220882 | DOI: 10.1080/21655979.2022.2037380
Adipose-derived mesenchymal stem cells (ADSCs) are a class of pluripotent stem cells isolated from the adipose tissue; they can differentiate into osteoblasts after induction and play an important role in bone repair. EGFL6 protein is secreted by adipocytes and osteoblasts and can promote endothelial cell migration and angiogenesis. This study aimed to explore the effect of recombinant EGFL6 protein on the osteogenic differentiation of ADSCs. The cells were incubated with fluorescein isothiocyanate-conjugated antibodies and analyzed by flow cytometry. Alizarin red staining and alkaline phosphatase staining were used to detect the osteogenic differentiation ability. mRNA expression was analyzed by real-time quantitative polymerase chain reaction (RT-qPCR). Protein expression was determined using Western blotting. The osteogenic differentiation ability of ADSCs isolated from the adipose tissue was significantly weakened after EGFL6 knockdown; this ability was restored upon the addition of EGFL6 recombinant protein. BMP2 knockdown inhibited the effect of EGFL6 recombinant protein on osteogenic differentiation. EGFL6 recombinant protein promoted osteogenic differentiation of ADSCs through the BMP2/SMAD4 signaling pathway. This may provide a potential target for the osteogenic differentiation of ADSCs.
Martin, M;Vermeiren, S;Bostaille, N;Eubelen, M;Spitzer, D;Vermeersch, M;Profaci, CP;Pozuelo, E;Toussay, X;Raman-Nair, J;Tebabi, P;America, M;De Groote, A;Sanderson, LE;Cabochette, P;Germano, RFV;Torres, D;Boutry, S;de Kerchove d'Exaerde, A;Bellefroid, EJ;Phoenix, TN;Devraj, K;Lacoste, B;Daneman, R;Liebner, S;Vanhollebeke, B;
PMID: 35175798 | DOI: 10.1126/science.abm4459
The blood-brain barrier (BBB) protects the central nervous system (CNS) from harmful blood-borne factors. Although BBB dysfunction is a hallmark of several neurological disorders, therapies to restore BBB function are lacking. An attractive strategy is to repurpose developmental BBB regulators, such as Wnt7a, into BBB-protective agents. However, safe therapeutic use of Wnt ligands is complicated by their pleiotropic Frizzled signaling activities. Taking advantage of the Wnt7a/b-specific Gpr124/Reck co-receptor complex, we genetically engineered Wnt7a ligands into BBB-specific Wnt activators. In a "hit-and-run" adeno-associated virus-assisted CNS gene delivery setting, these new Gpr124/Reck-specific agonists protected BBB function, thereby mitigating glioblastoma expansion and ischemic stroke infarction. This work reveals that the signaling specificity of Wnt ligands is adjustable and defines a modality to treat CNS disorders by normalizing the BBB.
Mascharak, S;Talbott, HE;Januszyk, M;Griffin, M;Chen, K;Davitt, MF;Demeter, J;Henn, D;Bonham, CA;Foster, DS;Mooney, N;Cheng, R;Jackson, PK;Wan, DC;Gurtner, GC;Longaker, MT;
PMID: 35077667 | DOI: 10.1016/j.stem.2021.12.011
Regeneration is the holy grail of tissue repair, but skin injury typically yields fibrotic, non-functional scars. Developing pro-regenerative therapies requires rigorous understanding of the molecular progression from injury to fibrosis or regeneration. Here, we report the divergent molecular events driving skin wound cells toward scarring or regenerative fates. We profile scarring versus YAP-inhibition-induced wound regeneration at the transcriptional (single-cell RNA sequencing), protein (timsTOF proteomics), and tissue (extracellular matrix ultrastructural analysis) levels. Using cell-surface barcoding, we integrate these data to reveal fibrotic and regenerative "molecular trajectories" of healing. We show that disrupting YAP mechanotransduction yields regenerative repair by fibroblasts with activated Trps1 and Wnt signaling. Finally, via in vivo gene knockdown and overexpression in wounds, we identify Trps1 as a key regulatory gene that is necessary and partially sufficient for wound regeneration. Our findings serve as a multi-omic map of wound regeneration and could have therapeutic implications for pathologic fibroses.
McDonald, GLK;Wang, M;Hammond, CL;Bergen, DJM;
PMID: 33668680 | DOI: 10.3390/biom11020277
Osteoporosis and other conditions associated with low bone density or quality are highly prevalent, are increasing as the population ages and with increased glucocorticoid use to treat conditions with elevated inflammation. There is an unmet need for therapeutics which can target skeletal precursors to induce osteoblast differentiation and osteogenesis. Genes associated with high bone mass represent interesting targets for manipulation, as they could offer ways to increase bone density. A damaging mutation in SMAD9 has recently been associated with high bone mass. Here we show that Smad9 labels groups of osteochondral precursor cells, which are not labelled by the other Regulatory Smads: Smad1 or Smad5. We show that Smad9+ cells are proliferative, and that the Smad9+ pocket expands following osteoblast ablation which induced osteoblast regeneration. We further show that treatment with retinoic acid, prednisolone, and dorsomorphin all alter Smad9 expression, consistent with the effects of these drugs on the skeletal system. Taken together these results demonstrate that Smad9+ cells represent an undifferentiated osteochondral precursor population, which can be manipulated by commonly used skeletal drugs. We conclude that Smad9 represents a target for future osteoanabolic therapies.
Park, J;Foox, J;Hether, T;Danko, D;Warren, S;Kim, Y;Reeves, J;Butler, D;Mozsary, C;Rosiene, J;Shaiber, A;Afshin, E;MacKay, M;Rendeiro, A;Bram, Y;Chandar, V;Geiger, H;Craney, A;Velu, P;Melnick, A;Hajirasouliha, I;Beheshti, A;Taylor, D;Saravia-Butler, A;Singh, U;Wurtele, E;Schisler, J;Fennessey, S;Corvelo, A;Zody, M;Germer, S;Salvatore, S;Levy, S;Wu, S;Tatonetti, N;Shapira, S;Salvatore, M;Westblade, L;Cushing, M;Rennert, H;Kriegel, A;Elemento, O;Imielinski, M;Rice, C;Borczuk, A;Meydan, C;Schwartz, R;Mason, C;
| DOI: 10.1016/j.xcrm.2022.100522
The molecular mechanisms underlying the clinical manifestations of COVID-19 and what distinguishes them from common seasonal influenza virus and other lung injury states such as Acute Respiratory Distress Syndrome, remains poorly understood. To address these challenges, we combine transcriptional profiling of 646 clinical nasopharyngeal swabs and 39 patient autopsy tissues to define body-wide transcriptome changes in response to COVID-19. We then match this data with spatial protein and expression profiling across 357 tissue sections from 16 representative patient lung samples and identify tissue compartment-specific damage wrought by SARS-CoV-2 infection, evident as a function of varying viral loads during the clinical course of infection and tissue type specific expression states. Overall, our findings reveal a systemic disruption of canonical cellular and transcriptional pathways across all tissues, which can inform subsequent studies to combat the mortality of COVID-19 and to better understand the molecular dynamics of lethal SARS-CoV-2 and other respiratory infections.
Pellegrino, G;Martin, M;Allet, C;Lhomme, T;Geller, S;Franssen, D;Mansuy, V;Manfredi-Lozano, M;Coutteau-Robles, A;Delli, V;Rasika, S;Mazur, D;Loyens, A;Tena-Sempere, M;Siepmann, J;Pralong, FP;Ciofi, P;Corfas, G;Parent, AS;Ojeda, SR;Sharif, A;Prevot, V;
PMID: 34795451 | DOI: 10.1038/s41593-021-00960-z
Neurons that produce gonadotropin-releasing hormone (GnRH), which control fertility, complete their nose-to-brain migration by birth. However, their function depends on integration within a complex neuroglial network during postnatal development. Here, we show that rodent GnRH neurons use a prostaglandin D2 receptor DP1 signaling mechanism during infancy to recruit newborn astrocytes that 'escort' them into adulthood, and that the impairment of postnatal hypothalamic gliogenesis markedly alters sexual maturation by preventing this recruitment, a process mimicked by the endocrine disruptor bisphenol A. Inhibition of DP1 signaling in the infantile preoptic region, where GnRH cell bodies reside, disrupts the correct wiring and firing of GnRH neurons, alters minipuberty or the first activation of the hypothalamic-pituitary-gonadal axis during infancy, and delays the timely acquisition of reproductive capacity. These findings uncover a previously unknown neuron-to-neural-progenitor communication pathway and demonstrate that postnatal astrogenesis is a basic component of a complex set of mechanisms used by the neuroendocrine brain to control sexual maturation.
Cheung, V;Chung, P;Bjorni, M;Shvareva, VA;Lopez, YC;Feinberg, EH;
PMID: 34936877 | DOI: 10.1016/j.celrep.2021.110131
Behavior arises from concerted activity throughout the brain. Consequently, a major focus of modern neuroscience is defining the physiology and behavioral roles of projection neurons linking different brain areas. Single-cell RNA sequencing has facilitated these efforts by revealing molecular determinants of cellular physiology and markers that enable genetically targeted perturbations such as optogenetics, but existing methods for sequencing defined projection populations are low throughput, painstaking, and costly. We developed a straightforward, multiplexed approach, virally encoded connectivity transgenic overlay RNA sequencing (VECTORseq). VECTORseq repurposes commercial retrogradely infecting viruses typically used to express functional transgenes (e.g., recombinases and fluorescent proteins) by treating viral transgene mRNA as barcodes within single-cell datasets. VECTORseq is compatible with different viral families, resolves multiple populations with different projection targets in one sequencing run, and identifies cortical and subcortical excitatory and inhibitory projection populations. Our study provides a roadmap for high-throughput identification of neuronal subtypes based on connectivity.
