Klingler, S;Hsu, KS;Hua, G;Martin, ML;Adileh, M;Baslan, T;Zhang, Z;Paty, PB;Fuks, Z;Brown, AM;Kolesnick, R;
PMID: 35260534 | DOI: 10.1172/jci.insight.153793
Recent data establish a logarithmic expansion of leucine rich repeat containing G protein coupled receptor 5-positive (Lgr5+) colonic epithelial stem cells (CESCs) in human colorectal cancer (CRC). Complementary studies using the murine 2-stage azoxymethane-dextran sulfate sodium (AOM-DSS) colitis-associated tumor model indicate early acquisition of Wnt pathway mutations drives CESC expansion during adenoma progression. Here, subdivision of the AOM-DSS model into in vivo and in vitro stages revealed DSS induced physical separation of CESCs from stem cell niche cells and basal lamina, a source of Wnt signals, within hours, disabling the stem cell program. While AOM delivery in vivo under non-adenoma-forming conditions yielded phenotypically normal mucosa and organoids derived thereof, niche injury ex vivo by progressive DSS dose escalation facilitated outgrowth of Wnt-independent dysplastic organoids. These organoids contained 10-fold increased Lgr5+ CESCs with gain-of-function Wnt mutations orthologous to human CRC driver mutations. We posit CRC originates by niche injury-induced outgrowth of normally suppressed mutated stem cells, consistent with models of adaptive oncogenesis.
Shen, TH;Stauber, J;Xu, K;Jacunski, A;Paragas, N;Callahan, M;Banlengchit, R;Levitman, AD;Desanti De Oliveira, B;Beenken, A;Grau, MS;Mathieu, E;Zhang, Q;Li, Y;Gopal, T;Askanase, N;Arumugam, S;Mohan, S;Good, PI;Stevens, JS;Lin, F;Sia, SK;Lin, CS;D'Agati, V;Kiryluk, K;Tatonetti, NP;Barasch, J;
PMID: 35230973 | DOI: 10.1172/jci.insight.146374
The current strategy to detect acute injury of kidney tubular cells relies on changes in serum levels of creatinine. Yet serum creatinine (sCr) is a marker of both functional and pathological processes and does not adequately assay tubular injury. In addition, sCr may require days to reach diagnostic thresholds, yet tubular cells respond with programs of damage and repair within minutes or hours. To detect acute responses to clinically relevant stimuli, we created mice expressing Rosa26-floxed-stop uracil phosphoribosyltransferase (Uprt) and inoculated 4-thiouracil (4-TU) to tag nascent RNA at selected time points. Cre-driven 4-TU-tagged RNA was isolated from intact kidneys and demonstrated that volume depletion and ischemia induced different genetic programs in collecting ducts and intercalated cells. Even lineage-related cell types expressed different genes in response to the 2 stressors. TU tagging also demonstrated the transient nature of the responses. Because we placed Uprt in the ubiquitously active Rosa26 locus, nascent RNAs from many cell types can be tagged in vivo and their roles interrogated under various conditions. In short, 4-TU labeling identifies stimulus-specific, cell-specific, and time-dependent acute responses that are otherwise difficult to detect with other technologies and are entirely obscured when sCr is the sole metric of kidney damage.
Harb, K;Richter, M;Neelagandan, N;Magrinelli, E;Harfoush, H;Kuechler, K;Henis, M;Hermanns-Borgmeyer, I;Calderon de Anda, F;Duncan, K;
PMID: 35262486 | DOI: 10.7554/eLife.55199
In the neocortex, functionally distinct areas process specific types of information. Area identity is established by morphogens and transcriptional master regulators, but downstream mechanisms driving area-specific neuronal specification remain unclear. Here, we reveal a role for RNA-binding proteins in defining area-specific cytoarchitecture. Mice lacking Pum2 or overexpressing human TDP-43 show apparent 'motorization' of layers IV and V of primary somatosensory cortex (S1), characterized by dramatic expansion of cells co-expressing Sox5 and Bcl11b/Ctip2, a hallmark of subcerebral projection neurons, at the expense of cells expressing the layer IV neuronal marker Rorβ. Moreover, retrograde labeling experiments with cholera toxin B in Pum2; Emx1-Cre and TDP43A315T mice revealed a corresponding increase in subcerebral connectivity of these neurons in S1. Intriguingly, other key features of somatosensory area identity are largely preserved, suggesting that Pum2 and TDP-43 may function in a downstream program, rather than controlling area identity per se. Transfection of primary neurons and in utero electroporation (IUE) suggest cell-autonomous and post-mitotic modulation of Sox5, Bcl11b/Ctip2, and Rorβ levels. Mechanistically, we find that Pum2 and TDP-43 directly interact with and affect the translation of mRNAs encoding Sox5, Bcl11b/Ctip2, and Rorβ. In contrast, effects on the levels of these mRNAs were not detectable in qRT-PCR or single-molecule fluorescent in situ hybridization assays, and we also did not detect effects on their splicing or polyadenylation patterns. Our results support the notion that post-transcriptional regulatory programs involving translational regulation and mediated by Pum2 and TDP-43 contribute to elaboration of area-specific neuronal identity and connectivity in the neocortex.
Lee, DR;Rhodes, C;Mitra, A;Zhang, Y;Maric, D;Dale, RK;Petros, TJ;
PMID: 35175194 | DOI: 10.7554/eLife.71864
The ventricular zone (VZ) of the nervous system contains radial glia cells that were originally considered relatively homogenous in their gene expression, but a detailed characterization of transcriptional diversity in these VZ cells has not been reported. Here, we performed single-cell RNA sequencing to characterize transcriptional heterogeneity of neural progenitors within the VZ and subventricular zone (SVZ) of the ganglionic eminences (GEs), the source of all forebrain GABAergic neurons. By using a transgenic mouse line to enrich for VZ cells, we characterize significant transcriptional heterogeneity, both between GEs and within spatial subdomains of specific GEs. Additionally, we observe differential gene expression between E12.5 and E14.5 VZ cells, which could provide insights into temporal changes in cell fate. Together, our results reveal a previously unknown spatial and temporal genetic diversity of VZ cells in the ventral forebrain that will aid our understanding of initial fate decisions in the forebrain.
Widmer, FC;O'Toole, SM;Keller, GB;
PMID: 35170429 | DOI: 10.7554/eLife.71476
The experience of coupling between motor output and visual feedback is necessary for the development of visuomotor skills and shapes visuomotor integration in visual cortex. Whether these experience-dependent changes of responses in V1 depend on modifications of the local circuit or are the consequence of circuit changes outside of V1 remains unclear. Here, we probed the role of N-methyl-d-aspartate (NMDA) receptor-dependent signaling, which is known to be involved in neuronal plasticity, in mouse primary visual cortex (V1) during visuomotor development. We used a local knockout of NMDA receptors and a photoactivatable inhibition of CaMKII in V1 during the first visual experience to probe for changes in neuronal activity in V1 as well as the influence on performance in a visuomotor task. We found that a knockout of NMDA receptors before, but not after, first visuomotor experience reduced responses to unpredictable stimuli, diminished the suppression of predictable feedback in V1, and impaired visuomotor skill learning later in life. Our results demonstrate that NMDA receptor-dependent signaling in V1 is critical during the first visuomotor experience for shaping visuomotor integration and enabling visuomotor skill learning.
Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases
Almamlouk, R;Kashour, T;Obeidat, S;Bois, MC;Maleszewski, JJ;Omrani, OA;Tleyjeh, R;Berbari, E;Chakhachiro, Z;Zein-Sabatto, B;Gerberi, D;Tleyjeh, IM;Cardiac Autopsy in COVID-19 Study Group, ;
PMID: 35339672 | DOI: 10.1016/j.cmi.2022.03.021
Many post-mortem studies addressing the cardiovascular effects of COVID-19 provided valuable information but were limited by their small sample size.The aim of this systematic review is to better understand the various aspects of the cardiovascular complications of COVID-19 by pooling data from a large number of autopsy studies.We searched online databases Ovid EBM Reviews, Ovid Embase, Ovid Medline, Scopus and Web of Science for the concepts of autopsy or histopathology combined with COVID-19 published between database inception to February 2021. We also searched for unpublished manuscripts using the medRxiv services operated by Cold Spring Harbor Laboratory.Articles were considered eligible for inclusion if they reported human post-mortem cardiovascular findings among individuals with confirmed SARS-CoV-2 infection.Studies were individually assessed for risk of selection bias, detection bias and reporting bias.Median prevalence of different autopsy findings with associated interquartile ranges.This review cohort contained 50 studies including 548 hearts. The median age of the deceased was 69 years. The most prevalent acute cardiovascular findings were myocardial necrosis (median=100.0%, IQR 20-100%, number of studies=9, number of patients=64) and myocardial edema (median=55.5%, IQR 19.5-92.5%, number of studies=4, number of patients=46). Median reported prevalence's of extensive, focal active and multifocal myocarditis were all 0.0%. The most prevalent chronic changes were myocyte hypertrophy (median=69.0%, IQR 46.8-92.1%) and fibrosis (median=35.0%, IQR 35.0-90.5%). SARS-CoV-2 was detected in the myocardium with median prevalence of 60.8% (IQR 40.4-95.6%).Our systematic review confirmed the high prevalence of acute and chronic cardiac pathologies in COVID-19, SARS-CoV-2 cardiac tropism, and the low prevalence of myocarditis in COVID-19 disease.
Bansard, L;Bouvet, O;Moutin, E;Le Gall, G;Giammona, A;Pothin, E;Bacou, M;Hassen-Khodja, C;Bordignon, B;Bourgaux, JF;Prudhomme, M;Hollande, F;Pannequin, J;Pascussi, JM;Planque, C;
PMID: 35276090 | DOI: 10.1016/j.stemcr.2022.02.005
Tumor recurrence is often attributed to cancer stem cells (CSCs). We previously demonstrated that down-regulation of Pregnane X Receptor (PXR) decreases the chemoresistance of CSCs and prevents colorectal cancer recurrence. Currently, no PXR inhibitor is usable in clinic. Here, we identify miR-148a as a targetable element upstream of PXR signaling in CSCs, which when over-expressed decreases PXR expression and impairs tumor relapse after chemotherapy in mouse tumor xenografts. We then develop a fluorescent reporter screen for miR-148a activators and identify the anti-helminthic drug niclosamide as an inducer of miR-148a expression. Consequently, niclosamide decreased PXR expression and CSC numbers in colorectal cancer patient-derived cell lines and synergized with chemotherapeutic agents to prevent CSC chemoresistance and tumor recurrence in vivo. Our study suggests that endogenous miRNA inducers is a viable strategy to down-regulate PXR and illuminates niclosamide as a neoadjuvant repurposing strategy to prevent tumor relapse in colon cancer.
Uehara, K;Koyanagi-Aoi, M;Koide, T;Itoh, T;Aoi, T;
PMID: 35245440 | DOI: 10.1016/j.stemcr.2022.02.002
Human gastric development has not been well studied. The generation of human pluripotent stem cell-derived gastric organoids (hGOs) comprising gastric marker-expressing epithelium without an apparent smooth muscle (SM) structure has been reported. We modified previously reported protocols to generate hGOs with muscularis mucosa (MM) from hiPSCs. Time course analyses revealed that epithelium development occurred prior to MM formation. Sonic hedgehog (SHH) and TGF-β1 were secreted by the epithelium. HH and TGF-β signal inhibition prevented subepithelial MM formation. A mechanical property of the substrate promoted SM differentiation around hGOs in the presence of TGF-β. TGF-β signaling was shown to influence the HH signaling and mechanical properties. In addition, clinical specimen findings suggested the involvement of TGF-β signaling in MM formation in recovering gastric ulcers. HH and TGF-β signaling from the epithelium to the stroma and the mechanical properties of the subepithelial environment may influence the emergence of MM in human stomach tissue.
Murlanova, K;Jouroukhin, Y;Huseynov, S;Pletnikova, O;Morales, MJ;Guan, Y;Baraban, JM;Bergles, DE;Pletnikov, MV;
PMID: 35275429 | DOI: 10.1002/glia.24169
Mitochondria are abundant in the fine processes of astrocytes, however, potential roles for astrocyte mitochondria remain poorly understood. In the present study, we performed a systematic examination of the effects of abnormal oxidative phosphorylation in astrocytes on several mouse behaviors. Impaired astrocyte oxidative phosphorylation was produced by astrocyte-specific deletion of the nuclear mitochondrial gene, Cox10, that encodes an accessory protein of complex IV, the protoheme:heme-O-farnesyl transferase. As expected, conditional deletion of the Cox10 gene in mice (cKO mice) significantly reduced expression of COX10 and Cytochrome c oxidase subunit I (MTCO1) of Complex IV, resulting in decreased oxidative phosphorylation without significantly affecting glycolysis. No effects of the deletion were observed on locomotor activity, anxiety-like behavior, nociception, or spontaneous alternation. Cox10 cKO female mice exhibited mildly impaired novel object recognition, while Cox10 cKO male mice were moderately deficient in trace fear conditioning. No group-related changes were observed in conditional place preference (CPP) that assessed effects of morphine on reward. In contrast to CPP, Cox10 cKO mice demonstrated significantly increased aversive behaviors produced by naloxone-precipitated withdrawal following chronic exposure to morphine, that is, jumping and avoidance behavior as assessed by conditional place aversion (CPA). Our study suggests that astrocyte oxidative phosphorylation may contribute to behaviors associated with greater cognitive load and/or aversive and stressful conditions.
Picard, A;Berney, X;Castillo-Armengol, J;Tarussio, D;Jan, M;Sanchez-Archidona, AR;Croizier, S;Thorens, B;
PMID: 35339728 | DOI: 10.1016/j.molmet.2022.101479
Glucagon secretion to stimulate hepatic glucose production is a first line of defense against hypoglycemia. This response is triggered by so far incompletely characterized central hypoglycemia sensing mechanisms, which control autonomous nervous activity and hormone secretion. The objective of this study was to identify novel hypothalamic genes controlling insulin-induced glucagon secretion.To obtain new information about the mechanisms of hypothalamic hypoglycemia sensing, we combined genetic and transcriptomic analysis of the glucagon response to insulin-induced hypoglycemia in a panel of BXD recombinant inbred mice.We identified two QTLs, on chromosome 8 and chromosome 15. We further investigated the role of Irak4 and Cpne8, both located in the chromosome 15 QTL, in C57BL/6J and DBA/2J mice, the BXD mouse parental strains. We found that the poor glucagon response of DBA/2J mice was associated with higher hypothalamic expression of Irak4, which encodes a kinase acting downstream of the interleukin-1 receptor (Il-1R), and of Il-ß when compared to C57BL/6J mice. We showed that intracerebroventricular administration of an Il-1R antagonist in DBA/2J restored insulin-induced glucagon secretion; this was associated with increased c-fos expression in the arcuate and paraventricular nuclei of the hypothalamus and with higher activation of both branches of the autonomous nervous system. Whole body inactivation of Cpne8, which encodes a Ca++-dependent regulator of membrane trafficking and exocytosis had, however, no impact on insulin-induced glucagon secretion.Collectively, our data identify Irak4 as a genetically controlled regulator of hypoglycemia-activated hypothalamic neurons and glucagon secretion.
Brain, behavior, and immunity
Katayama, PL;Leirão, IP;Kanashiro, A;Luiz, JPM;Cunha, FQ;Navegantes, LCC;Menani, JV;Zoccal, DB;Colombari, DSA;Colombari, E;
PMID: 35339628 | DOI: 10.1016/j.bbi.2022.03.014
Recent evidence has suggested that the carotid bodies might act as immunological sensors, detecting pro-inflammatory mediators and signalling to the central nervous system, which, in turn, orchestrates autonomic responses. Here, we confirmed that the TNF-α receptor type I is expressed in the carotid bodies of rats. The systemic administration of TNF-α increased carotid body afferent discharge and activated glutamatergic neurons in the nucleus tractus solitarius (NTS) that project to the rostral ventrolateral medulla (RVLM), where many pre-sympathetic neurons reside. The activation of these neurons was accompanied by an increase in splanchnic sympathetic nerve activity. Carotid body ablation blunted the TNF-α-induced activation of RVLM-projecting NTS neurons and the increase in splanchnic sympathetic nerve activity. Finally, plasma and spleen levels of cytokines after TNF-α administration were higher in rats subjected to either carotid body ablation or splanchnic sympathetic denervation. Collectively, our findings indicate that the carotid body detects circulating TNF-α to activate a counteracting sympathetic anti-inflammatory mechanism.
Emerging microbes & infections
Gao, L;Jiao, YM;Ma, P;Sun, L;Zhao, H;Guo, AL;Fan, X;Zhang, C;Song, JW;Zhang, JY;Lu, F;Wang, FS;
PMID: 35253610 | DOI: 10.1080/22221751.2022.2049982
Semen is a known vector for both human immunodeficiency virus (HIV) infection and transmission. However, the distribution and characteristics of HIV-infected cells in semen remain unclear. Investigating the possibility of transmission through the spermatozoon in semen is of great clinical significance to improve the strategies for exposure prevention and assisted reproduction for HIV-infected partners. Twenty-six HIV-infected patients, including twelve treatment-naïve (TN) patients and fourteen antiretroviral treated (ART) patients, were enrolled in this study. HIV p24 protein in spermatozoa was detected using imaging flow cytometry and immunohistochemistry, and HIV RNA was identified using next-generation RNAscope in situ hybridization. Additionally, we described the rates of HIV-positive spermatozoon and CD4+ T lymphocytes in semen, and found that p24+ spermatozoon were mainly CD4 negative regardless of whether the patients received ART. Of note, p24-positive cells in semen are predominantly spermatozoa, and we confirmed that motile spermatozoa carried HIV into peripheral blood mononuclear cells of healthy men in vitro. Our findings provide evidence regarding the risk of HIV-infected spermatozoa.