Hartwig J, Tarbashevich K, Seggewiß J, Stehling M, Bandemer J, Grimaldi C, Paksa A, Groß-Thebing T, Meyen D, Raz E.
PMID: 25049415 | DOI: 201400043
The control over the acquisition of cell motility is central for a variety of biological processes in development, homeostasis, and disease. An attractive in vivo model for investigating the regulation of migration initiation is that of primordial germ cells (PGCs) in zebrafish embryos. In this study, we show that, following PGC specification, the cells can polarize but do not migrate before the time chemokine-encoded directional cues are established. We found that the regulator of G-protein signaling 14a protein, whose RNA is a newly identified germ plasm component, regulates the temporal relations between the appearance of the guidance molecules and the acquisition of cellular motility by regulating E-cadherin levels.
Li L, Ning G, Yang S, Yan Y, Cao Y, Wang Q.
PMID: 30763319 | DOI: 10.1371/journal.pgen.1007996
Pharyngeal pouches, a series of outpocketings that bud from the foregut endoderm, are essential to the formation of craniofacial skeleton as well as several important structures like parathyroid and thymus. However, whether pharyngeal pouch progenitors exist in the developing gut tube remains unknown. Here, taking advantage of cell lineage tracing and transgenic ablation technologies, we identified a population of nkx2.3+ pouch progenitors in zebrafish embryos and demonstrated an essential requirement of ectodermal BMP2b for their specification.At early somite stages, nkx2.3+ cells located at lateral region of pharyngeal endoderm give rise to the pouch epithelium except a subpopulation expressing pdgfαa rather than nkx2.3. A small-scale screen of chemical inhibitors reveals that BMP signaling is necessary to specify these progenitors. Loss-of-function analyses show that BMP2b, expressed in the pharyngeal ectoderm, actives Smad effectors in endodermal cells to induce nkx2.3+ progenitors. Collectively, our study provides in vivo evidence for the existence of pouch progenitors and highlights the importance of BMP2b signaling in progenitor specification.
Zhang, C;Wei, B;Liu, Z;Yao, W;Li, Y;Lu, J;Ge, C;Yu, X;Li, D;Zhu, Y;Shang, C;Jin, N;Li, X;
PMID: 36721152 | DOI: 10.1186/s12985-023-01971-x
Coronavirus disease 2019 is a global pandemic caused by SARS-CoV-2. The emergence of its variant strains has posed a considerable challenge to clinical treatment. Therefore, drugs capable of inhibiting SARS-CoV-2 infection, regardless of virus variations, are in urgently need. Our results showed that the endosomal acidification inhibitor, Bafilomycin A1 (Baf-A1), had an inhibitory effect on the viral RNA synthesis of SARS-CoV-2, and its Beta and Delta variants at the concentration of 500 nM. Moreover, the human lung xenograft mouse model was used to investigate the anti-SARS-CoV-2 effect of Baf-A1. It was found that Baf-A1 significantly inhibited SARS-CoV-2 replication in the human lung xenografts by in situ hybridization and RT-PCR assays. Histopathological examination showed that Baf-A1 alleviated SARS-CoV-2-induced diffuse inflammatory infiltration of granulocytes and macrophages and alveolar endothelial cell death in human lung xenografts. In addition, immunohistochemistry analysis indicated that Baf-A1 decreased inflammatory exudation and infiltration in SARS-CoV-2-infected human lung xenografts. Therefore, Baf-A1 may be a candidate drug for SARS-CoV-2 treatment.
Korchynska, S;Rebernik, P;Pende, M;Boi, L;Alpár, A;Tasan, R;Becker, K;Balueva, K;Saghafi, S;Wulff, P;Horvath, TL;Fisone, G;Dodt, HU;Hökfelt, T;Harkany, T;Romanov, RA;
PMID: 36209152 | DOI: 10.1038/s41467-022-33584-3
The lateral septum (LS) has been implicated in the regulation of locomotion. Nevertheless, the neurons synchronizing LS activity with the brain's clock in the suprachiasmatic nucleus (SCN) remain unknown. By interrogating the molecular, anatomical and physiological heterogeneity of dopamine neurons of the periventricular nucleus (PeVN; A14 catecholaminergic group), we find that Th+/Dat1+ cells from its anterior subdivision innervate the LS in mice. These dopamine neurons receive dense neuropeptidergic innervation from the SCN. Reciprocal viral tracing in combination with optogenetic stimulation ex vivo identified somatostatin-containing neurons in the LS as preferred synaptic targets of extrahypothalamic A14 efferents. In vivo chemogenetic manipulation of anterior A14 neurons impacted locomotion. Moreover, chemogenetic inhibition of dopamine output from the anterior PeVN normalized amphetamine-induced hyperlocomotion, particularly during sedentary periods. Cumulatively, our findings identify a hypothalamic locus for the diurnal control of locomotion and pinpoint a midbrain-independent cellular target of psychostimulants.
Mao, Q;Chu, S;Shapiro, S;Young, L;Russo, M;De Paepe, ME;
PMID: 34929459 | DOI: 10.1016/j.placenta.2021.12.002
Recent evidence supports the - rare - occurrence of vertical transplacental SARS-CoV-2 transmission. We previously determined that placental expression of angiotensin-converting enzyme 2 (ACE2), the SARS-CoV-2 receptor, and associated viral cell entry regulators is upregulated by hypoxia. In the present study, we utilized a clinically relevant model of SARS-CoV-2-associated chronic histiocytic intervillositis/massive perivillous fibrin deposition (CHIV/MPFVD) to test the hypothesis that placental hypoxia may facilitate placental SARS-CoV-2 infection.We performed a comparative immunohistochemical and/or RNAscope in-situ hybridization analysis of carbonic anhydrase IX (CAIX, hypoxia marker), ACE2 and SARS-CoV-2 expression in free-floating versus fibrin-encased chorionic villi in a 20-weeks' gestation placenta with SARS-CoV-2-associated CHIV/MPVFD.The levels of CAIX and ACE2 immunoreactivity were significantly higher in trophoblastic cells of fibrin-encased villi than in those of free-floating villi, consistent with hypoxia-induced ACE2 upregulation. SARS-CoV-2 showed a similar preferential localization to trophoblastic cells of fibrin-encased villi.The localization of SARS-CoV-2 to hypoxic, fibrin-encased villi in this placenta with CHIV/MPVFD suggests placental infection and, therefore, transplacental SARS-CoV-2 transmission may be promoted by hypoxic conditions, mediated by ACE2 and similar hypoxia-sensitive viral cell entry mechanisms. Understanding of a causative link between placental hypoxia and SARS-CoV-2 transmittability may potentially lead to the development of alternative strategies for prevention of intrauterine COVID-19 transmission.
McDonald, JT;Enguita, FJ;Taylor, D;Griffin, RJ;Priebe, W;Emmett, MR;Sajadi, MM;Harris, AD;Clement, J;Dybas, JM;Aykin-Burns, N;Guarnieri, JW;Singh, LN;Grabham, P;Baylin, SB;Yousey, A;Pearson, AN;Corry, PM;Saravia-Butler, A;Aunins, TR;Sharma, S;Nagpal, P;Meydan, C;Foox, J;Mozsary, C;Cerqueira, B;Zaksas, V;Singh, U;Wurtele, ES;Costes, SV;Davanzo, GG;Galeano, D;Paccanaro, A;Meinig, SL;Hagan, RS;Bowman, NM;UNC COVID-19 Pathobiology Consortium, ;Wolfgang, MC;Altinok, S;Sapoval, N;Treangen, TJ;Moraes-Vieira, PM;Vanderburg, C;Wallace, DC;Schisler, JC;Mason, CE;Chatterjee, A;Meller, R;Beheshti, A;
PMID: 34624208 | DOI: 10.1016/j.celrep.2021.109839
MicroRNAs (miRNAs) are small non-coding RNAs involved in post-transcriptional gene regulation that have a major impact on many diseases and provide an exciting avenue toward antiviral therapeutics. From patient transcriptomic data, we determined that a circulating miRNA, miR-2392, is directly involved with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) machinery during host infection. Specifically, we show that miR-2392 is key in driving downstream suppression of mitochondrial gene expression, increasing inflammation, glycolysis, and hypoxia, as well as promoting many symptoms associated with coronavirus disease 2019 (COVID-19) infection. We demonstrate that miR-2392 is present in the blood and urine of patients positive for COVID-19 but is not present in patients negative for COVID-19. These findings indicate the potential for developing a minimally invasive COVID-19 detection method. Lastly, using in vitro human and in vivo hamster models, we design a miRNA-based antiviral therapeutic that targets miR-2392, significantly reduces SARS-CoV-2 viability in hamsters, and may potentially inhibit a COVID-19 disease state in humans.
Evidence for residual SARS-CoV-2 in glioblastoma tissue of a convalescent patient
Lei, J;Liu, Y;Xie, T;Yao, G;Wang, G;Diao, B;Song, J;
PMID: 33994523 | DOI: 10.1097/WNR.0000000000001654
Since coronavirus disease 2019 (COVID-19) swept all over the world, several studies have shown the susceptibility of a patient with cancer to COVID-19. In this case, the removed glioblastoma multiforme (GBM)-adjacent (GBM-A), GBM-peritumor and GBM-central (GBM-C) tissues from a convalescent patient of COVID-19, who also suffered from glioblastoma meanwhile, together with GBM-A and GBM tissues from a patient without COVID-19 history as negative controls, were used for RNA ISH, electron microscopy observing and immunohistochemical staining of ACE2 and the virus antigen (N protein). The results of RNA ISH, electron microscopy observing showed that SARS-CoV-2 directly infects some cells within human GBM tissues and SARS-CoV-2 in GBM-C tissue still exists even when it is cleared elsewhere. Immunohistochemical staining of ACE2 and N protein showed that the expressions of ACE2 are significantly higher in specimens, including GBM-C tissue from COVID-19 patient than other types of tissue. The unique phenomenon suggests that the surgical protection level should be upgraded even if the patient is in a convalescent period and the pharyngeal swab tests show negative results. Furthermore, more attention should be paid to confirm whether the shelter-like phenomenon happens in other malignancies due to the similar microenvironment and high expression of ACE2 in some malignancies.
Knowland D, Lilascharoen V, Pacia CP, Shin S, Wang EH, Lim BK.
PMID: 28689640 | DOI: 10.1016/j.cell.2017.06.015
Major depressive disorder (MDD) patients display a common but often variable set of symptoms making successful, sustained treatment difficult to achieve. Separate depressive symptoms may be encoded by differential changes in distinct circuits in the brain, yet how discrete circuits underlie behavioral subsets of depression and how they adapt in response to stress has not been addressed. We identify two discrete circuits of parvalbumin-positive (PV) neurons in the ventral pallidum (VP) projecting to either the lateral habenula or ventral tegmental area contributing to depression. We find that these populations undergo different electrophysiological adaptations in response to social defeat stress, which are normalized by antidepressant treatment. Furthermore, manipulation of each population mediates either social withdrawal or behavioral despair, but not both. We propose that distinct components of the VP PV circuit can subserve related, yet separate depressive-like phenotypes in mice, which could ultimately provide a platform for symptom-specific treatments of depression.
Journal of neuropathology and experimental neurology
Normandin, E;Valizadeh, N;Rudmann, EA;Uddin, R;Dobbins, ST;MacInnis, BL;Padera, RF;Siddle, KJ;Lemieux, JE;Sabeti, PC;Mukerji, SS;Solomon, IH;
PMID: 36847705 | DOI: 10.1093/jnen/nlad015
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is continually evolving resulting in variants with increased transmissibility, more severe disease, reduced effectiveness of treatments or vaccines, or diagnostic detection failure. The SARS-CoV-2 Delta variant (B.1.617.2 and AY lineages) was the dominant circulating strain in the United States from July to mid-December 2021, followed by the Omicron variant (B.1.1.529 and BA lineages). Coronavirus disease 2019 (COVID-19) has been associated with neurological sequelae including loss of taste/smell, headache, encephalopathy, and stroke, yet little is known about the impact of viral strain on neuropathogenesis. Detailed postmortem brain evaluations were performed for 22 patients from Massachusetts, including 12 who died following infection with Delta variant and 5 with Omicron variant, compared to 5 patients who died earlier in the pandemic. Diffuse hypoxic injury, occasional microinfarcts and hemorrhage, perivascular fibrinogen, and rare lymphocytes were observed across the 3 groups. SARS-CoV-2 protein and RNA were not detected in any brain samples by immunohistochemistry, in situ hybridization, or real-time quantitative PCR. These results, although preliminary, demonstrate that, among a subset of severely ill patients, similar neuropathological features are present in Delta, Omicron, and non-Delta/non-Omicron variant patients, suggesting that SARS-CoV-2 variants are likely to affect the brain by common neuropathogenic mechanisms.
Gynecologic and obstetric investigation
Shen, WB;Turan, S;Wang, B;Cojocaru, L;Harman, C;Logue, J;Reece, EA;Frieman, MB;Yang, P;
PMID: 35526532 | DOI: 10.1159/000524905
Studies indicate a very low rate of SARS-CoV-2 detection in the placenta or occasionally a low rate of vertical transmission in COVID-19 pregnancy. SARS-CoV-2 Delta variant has become a dominant strain over the world and possesses higher infectivity due to mutations in its spike receptor-binding motif.To determine whether SARS-CoV-2 Delta variant has increased potential for placenta infection and vertical transmission, we analyzed SARS-CoV-2 infection in the placenta, umbilical cord, and fetal membrane from a case that unvaccinated mother and her neonate were COVID-19 positive. A 35-year-old primigravida with COVID-19 underwent an emergent cesarean delivery due to placental abruption in the setting of premature rupture of membranes. The neonate tested positive for SARS-CoV-2 within the first 24 hours, and then again on days of life 2, 6, 13, and 21. The placenta exhibited intervillositis, increased fibrin deposition, and syncytiotrophoblast necrosis. Sequencing of viral RNA from fixed placental tissue revealed SAR-CoV-2 B.1.167.2 (Delta) variant. Both spike protein and viral RNA were abundantly present in syncytiotrophoblasts, cytotrophoblasts, umbilical cord vascular endothelium, and fetal membranes.We report with strong probability the first SARS-CoV-2 Delta variant transplacental transmission. Placental cells exhibited extensive apoptosis, senescence, and ferroptosis after SARS-CoV-2 Delta infection.S. Karger AG, Basel.
Nanotube-like processes facilitate material transfer between photoreceptors
Kalargyrou, AA;Basche, M;Hare, A;West, EL;Smith, AJ;Ali, RR;Pearson, RA;
PMID: 34494703 | DOI: 10.15252/embr.202153732
Neuronal communication is typically mediated via synapses and gap junctions. New forms of intercellular communication, including nanotubes (NTs) and extracellular vesicles (EVs), have been described for non-neuronal cells, but their role in neuronal communication is not known. Recently, transfer of cytoplasmic material between donor and host neurons ("material transfer") was shown to occur after photoreceptor transplantation. The cellular mechanism(s) underlying this surprising finding are unknown. Here, using transplantation, primary neuronal cultures and the generation of chimeric retinae, we show for the first time that mammalian photoreceptor neurons can form open-end NT-like processes. These processes permit the transfer of cytoplasmic and membrane-bound molecules in culture and after transplantation and can mediate gain-of-function in the acceptor cells. Rarely, organelles were also observed to transfer. Strikingly, use of chimeric retinae revealed that material transfer can occur between photoreceptors in the intact adult retina. Conversely, while photoreceptors are capable of releasing EVs, at least in culture, these are taken up by glia and not by retinal neurons. Our findings provide the first evidence of functional NT-like processes forming between sensory neurons in culture and in vivo.
Intravenous, Intratracheal, and Intranasal Inoculation of Swine with SARS-CoV-2
Buckley, A;Falkenberg, S;Martins, M;Laverack, M;Palmer, MV;Lager, K;Diel, DG;
PMID: 34452371 | DOI: 10.3390/v13081506
Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the susceptibility of animals and their potential to act as reservoirs or intermediate hosts for the virus has been of significant interest. Pigs are susceptible to multiple coronaviruses and have been used as an animal model for other human infectious diseases. Research groups have experimentally challenged swine with human SARS-CoV-2 isolates with results suggesting limited to no viral replication. For this study, a SARS-CoV-2 isolate obtained from a tiger which is identical to human SARS-CoV-2 isolates detected in New York City and contains the D614G S mutation was utilized for inoculation. Pigs were challenged via intravenous, intratracheal, or intranasal routes of inoculation (n = 4/route). No pigs developed clinical signs, but at least one pig in each group had one or more PCR positive nasal/oral swabs or rectal swabs after inoculation. All pigs in the intravenous group developed a transient neutralizing antibody titer, but only three other challenged pigs developed titers greater than 1:8. No gross or histologic changes were observed in tissue samples collected at necropsy. In addition, no PCR positive samples were positive by virus isolation. Inoculated animals were unable to transmit virus to naïve contact animals. The data from this experiment as well as from other laboratories supports that swine are not likely to play a role in the epidemiology and spread of SARS-CoV-2.
