Journal of the College of Physicians and Surgeons--Pakistan : JCPSP
Dogan, Y;Onalan, E;Cavli, C;Onalan, EE;Yakar, B;Donder, E;
PMID: 34794279 | DOI: 10.29271/jcpsp.2021.12.1412
To determine the difference in serum Elabela level in hypertensive patients with and without nephropathy compared to the healthy control group. Study Desing: Cross-sectional descriptive study.Fırat University Medical School, Elazig, Turkey between December 2018 and November 2020.The cross-sectional descriptive study consisted of 37 patients with hypertensive nephropathy (group 3), 50 hypertensive patients without nephropathy (group 2), and 50 healthy controls (group 1). Hypertensive nephropathy was defined as serum creatinine ≥1.8 mg / dl or GFR <40 ml / minute. Biochemical parameters (Glucose, AST, ALT, urea, creatinine, lipid levels, hemogram, calcium, phosphorus, parathormone) and the levels of serum Elabela were evaluated and compared.There was no significant difference in age (0.270) and gender (0.951) between groups. The median Elabela levels of the three groups were 40.3 ng/mL (22.5-54.6), 5.1 ng/mL (3.7-8.3), 9.2 ng/mL (6.1-23.1), respectively with a significant difference (p<0.001).The plasma levels of Elabela were lower in the case of hypertension, independent of nephropathy. However, this decrease is not specific for nephropathy and may be due to other accompanying chronic diseases. Key Words: Hypertension, Hypertensive nephropathy, Elabela.
Williaume, G;de Buyl, S;Sirour, C;Haupaix, N;Bettoni, R;Imai, KS;Satou, Y;Dupont, G;Hudson, C;Yasuo, H;
PMID: 34672970 | DOI: 10.1016/j.devcel.2021.09.025
Precise control of lineage segregation is critical for the development of multicellular organisms, but our quantitative understanding of how variable signaling inputs are integrated to activate lineage-specific gene programs remains limited. Here, we show how precisely two out of eight ectoderm cells adopt neural fates in response to ephrin and FGF signals during ascidian neural induction. In each ectoderm cell, FGF signals activate ERK to a level that mirrors its cell contact surface with FGF-expressing mesendoderm cells. This gradual interpretation of FGF inputs is followed by a bimodal transcriptional response of the immediate early gene, Otx, resulting in its activation specifically in the neural precursors. At low levels of ERK, Otx is repressed by an ETS family transcriptional repressor, ERF2. Ephrin signals are critical for dampening ERK activation levels across ectoderm cells so that only neural precursors exhibit above-threshold levels, evade ERF repression, and "switch on" Otx transcription.
Maksymetz, J;Byun, NE;Luessen, DJ;Li, B;Barry, RL;Gore, JC;Niswender, CM;Lindsley, CW;Joffe, ME;Conn, PJ;
PMID: 34731619 | DOI: 10.1016/j.celrep.2021.109950
Evidence for prefrontal cortical (PFC) GABAergic dysfunction is one of the most consistent findings in schizophrenia and may contribute to cognitive deficits. Recent studies suggest that the mGlu1 subtype of metabotropic glutamate receptor regulates cortical inhibition; however, understanding the mechanisms through which mGlu1 positive allosteric modulators (PAMs) regulate PFC microcircuit function and cognition is essential for advancing these potential therapeutics toward the clinic. We report a series of electrophysiology, optogenetic, pharmacological magnetic resonance imaging, and animal behavior studies demonstrating that activation of mGlu1 receptors increases inhibitory transmission in the prelimbic PFC by selective excitation of somatostatin-expressing interneurons (SST-INs). An mGlu1 PAM reverses cortical hyperactivity and concomitant cognitive deficits induced by N-methyl-d-aspartate (NMDA) receptor antagonists. Using in vivo optogenetics, we show that prelimbic SST-INs are necessary for mGlu1 PAM efficacy. Collectively, these findings suggest that mGlu1 PAMs could reverse cortical GABAergic deficits and exhibit efficacy in treating cognitive dysfunction in schizophrenia.
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
Han, J;Andreu, V;Langreck, C;Pekarskaya, EA;Grinnell, SG;Allain, F;Magalong, V;Pintar, J;Kieffer, BL;Harris, AZ;Javitch, JA;Hen, R;Nautiyal, KM;
PMID: 34593976 | DOI: 10.1038/s41386-021-01192-2
Tianeptine is an atypical antidepressant used in Europe to treat patients who respond poorly to selective serotonin reuptake inhibitors (SSRIs). The recent discovery that tianeptine is a mu opioid receptor (MOR) agonist has provided a potential avenue for expanding our understanding of antidepressant treatment beyond the monoamine hypothesis. Thus, our studies aim to understand the neural circuits underlying tianeptine's antidepressant effects. We show that tianeptine induces rapid antidepressant-like effects in mice after as little as one week of treatment. Critically, we also demonstrate that tianeptine's mechanism of action is distinct from fluoxetine in two important aspects: (1) tianeptine requires MORs for its chronic antidepressant-like effect, while fluoxetine does not, and (2) unlike fluoxetine, tianeptine does not promote hippocampal neurogenesis. Using cell-type specific MOR knockouts we further show that MOR expression on GABAergic cells-specifically somatostatin-positive neurons-is necessary for the acute and chronic antidepressant-like responses to tianeptine. Using central infusion of tianeptine, we also implicate the ventral hippocampus as a potential site of antidepressant action. Moreover, we show a dissociation between the antidepressant-like phenotype and other opioid-like phenotypes resulting from acute tianeptine administration such as analgesia, conditioned place preference, and hyperlocomotion. Taken together, these results suggest a novel entry point for understanding what circuit dysregulations may occur in depression, as well as possible targets for the development of new classes of antidepressant drugs.
The noncoding genome and hearing loss
Avraham, KB;Khalaily, L;Noy, Y;Kamal, L;Koffler-Brill, T;Taiber, S;
PMID: 34491412 | DOI: 10.1007/s00439-021-02359-z
The age of sequencing has provided unprecedented insights into the human genome. The coding region of the genome comprises nearly 20,000 genes, of which approximately 4000 are associated with human disease. Beyond the protein-coding genome, which accounts for only 3% of the genome, lies a vast pool of regulatory elements in the form of promoters, enhancers, RNA species, and other intricate elements. These features undoubtably influence human health and disease, and as a result, a great deal of effort is currently being invested in deciphering their identity and mechanism. While a paucity of material has caused a lag in identifying these elements in the inner ear, the emergence of technologies for dealing with a minimal number of cells now has the field working overtime to catch up. Studies on microRNAs (miRNAs), long non-coding RNAs (lncRNAs), methylation, histone modifications, and more are ongoing. A number of microRNAs and other noncoding elements are known to be associated with hearing impairment and there is promise that regulatory elements will serve as future tools and targets of therapeutics and diagnostics. This review covers the current state of the field and considers future directions for the noncoding genome and implications for hearing loss.
Spatial mapping of the tumor immune microenvironment
Engineering Technologies and Clinical Translation
Wu, Y;Pagacz, J;Emery, S;Kron, S;Lee, S;
| DOI: 10.1016/B978-0-323-90949-5.00009-7
To replace one-size-fits-all cancer immunotherapy with personalized treatment, biomarkers of response and resistance as well as assays to evaluate them in each patient are essential. Among likely determinants of response, the spatial locations and activation states of the immune infiltrate appear critical. Current clinical methods for tissue analysis such as immunohistochemistry are poorly matched to the heterogeneity of the tumor immune microenvironment (TIME). However, multiple tools for analysis of the TIME can now image panels of biomarkers in a single experiment, permit deep profiling to measure dozens of immune features in each sample, and/or facilitate unbiased multiomic analysis at high spatial resolution. Several assays are commercialized with some nearing clinical adoption. In this chapter, we present a broad overview of established and emerging technologies that enable multiplexed detection and spatial mapping of cellular and molecular features of the TIME, highlighting advantages and disadvantages as well as opportunities for future development.
Using single-nucleus RNA-sequencing to interrogate transcriptomic profiles of archived human pancreatic islets
Basile, G;Kahraman, S;Dirice, E;Pan, H;Dreyfuss, JM;Kulkarni, RN;
PMID: 34376240 | DOI: 10.1186/s13073-021-00941-8
Human pancreatic islets are a central focus of research in metabolic studies. Transcriptomics is frequently used to interrogate alterations in cultured human islet cells using single-cell RNA-sequencing (scRNA-seq). We introduce single-nucleus RNA-sequencing (snRNA-seq) as an alternative approach for investigating transplanted human islets.The Nuclei EZ protocol was used to obtain nuclear preparations from fresh and frozen human islet cells. Such preparations were first used to generate snRNA-seq datasets and compared to scRNA-seq output obtained from cells from the same donor. Finally, we employed snRNA-seq to obtain the transcriptomic profile of archived human islets engrafted in immunodeficient animals.We observed virtually complete concordance in identifying cell types and gene proportions as well as a strong association of global and islet cell type gene signatures between scRNA-seq and snRNA-seq applied to fresh and frozen cultured or transplanted human islet samples.We propose snRNA-seq as a reliable strategy to probe transcriptomic profiles of freshly harvested or frozen sources of transplanted human islet cells especially when scRNA-seq is not ideal.
Nociceptor subtypes are born continuously over DRG development
Landy, M;Goyal, M;Lai, H;
| DOI: 10.1016/j.ydbio.2021.07.018
Sensory neurogenesis in the dorsal root ganglion (DRG) occurs in two waves of differentiation with larger, myelinated proprioceptive and low-threshold mechanoreceptor (LTMR) neurons differentiating before smaller, unmyelinated (C) nociceptive neurons. This temporal difference was established from early birthdating studies based on DRG soma cell size. However, distinctions in birthdates between molecular subtypes of sensory neurons, particularly nociceptors, is unknown. Here, we assess the birthdate of lumbar DRG neurons in mice using a thymidine analog, EdU, to label developing neurons exiting mitosis combined with co-labeling of known sensory neuron markers. We find that different nociceptor subtypes are born on similar timescales, with continuous births between E9.5 to E13.5, and peak births from E10.5 to E11.5. Notably, we find that thinly myelinated Aδ-fiber nociceptors and peptidergic C-fibers are born more broadly between E10.5 and E11.5 than previously thought and that non-peptidergic C-fibers and C-LTMRs are born with a peak birth date of E11.5. Moreover, we find that the percentages of nociceptor subtypes born at a particular timepoint are the same for any given nociceptor cell type marker, indicating that intrinsic or extrinsic influences on cell type diversity are occurring similarly across developmental time. Overall, the patterns of birth still fit within the classical “two wave” description, as touch and proprioceptive fibers are born primarily at E10.5, but suggest that nociceptors have a slightly broader wave of birthdates with different nociceptor subtypes continually differentiating throughout sensory neurogenesis irrespective of myelination.
Airway basal stem cells reutilize the embryonic proliferation regulator, Tgfβ-Id2 axis, for tissue regeneration
Kiyokawa, H;Yamaoka, A;Matsuoka, C;Tokuhara, T;Abe, T;Morimoto, M;
PMID: 34129836 | DOI: 10.1016/j.devcel.2021.05.016
During development, quiescent airway basal stem cells are derived from proliferative primordial progenitors through the cell-cycle slowdown. In contrast, basal cells contribute to adult tissue regeneration by shifting from slow cycling to proliferating and subsequently back to slow cycling. Although sustained proliferation results in tumorigenesis, the molecular mechanisms regulating these transitions remain unknown. Using temporal single-cell transcriptomics of developing murine airway progenitors and genetic validation experiments, we found that TGF-β signaling decelerated cell cycle by inhibiting Id2 and contributed to slow-cycling basal cell specification during development. In adult tissue regeneration, reduced TGF-β signaling restored Id2 expression and initiated regeneration. Id2 overexpression and Tgfbr2 knockout enhanced epithelial proliferation; however, persistent Id2 expression drove basal cell hyperplasia that resembled a precancerous state. Together, the TGF-β-Id2 axis commonly regulates the proliferation transitions in basal cells during development and regeneration, and its fine-tuning is critical for normal regeneration while avoiding basal cell hyperplasia.
Single-cell RNA sequencing reveals Nestin+ active neural stem cells outside the central canal after spinal cord injury
Science China. Life sciences
Shu, M;Xue, X;Nie, H;Wu, X;Sun, M;Qiao, L;Li, X;Xu, B;Xiao, Z;Zhao, Y;Fan, Y;Chen, B;Zhang, J;Shi, Y;Yang, Y;Lu, F;Dai, J;
PMID: 34061300 | DOI: 10.1007/s11427-020-1930-0
Neural stem cells (NSCs) in the spinal cord hold great potential for repair after spinal cord injury (SCI). The ependyma in the central canal (CC) region has been considered as the NSCs source in the spinal cord. However, the ependyma function as NSCs after SCI is still under debate. We used Nestin as a marker to isolate potential NSCs and their immediate progeny, and characterized the cells before and after SCI by single-cell RNA-sequencing (scRNA-seq). We identified two subgroups of NSCs: the subgroup located within the CC cannot prime to active NSCs after SCI, while the subgroup located outside the CC were activated and exhibited the active NSCs properties after SCI. We demonstrated the comprehensive dynamic transcriptome of NSCs from quiescent to active NSCs after SCI. This study reveals that Nestin+ cells outside CC were NSCs that activated upon SCI and may thus serve as endogenous NSCs for regenerative treatment of SCI in the future.
ATAK receptors, harnessing innate immunity to program myeloid cells to kill cancer
Wang, Y;Diwanji, N;Nicholson, T;Mukherjee, S;Getts, D;
| DOI: 10.1016/S1465324921004217
Background & Aim: T cells therapies have revolutionized cancer treatment for many patients. However, for the majority of patients with advanced solid tumors, sustained clinical benefit has not been achieved. Unlike T cells, myeloid cells readily accumulate in tumors, in some cases contributing up to 50% of the tumor mass. More recently, the potential for engaging innate immune signaling sensors such as Toll-like receptors and STING-cGAS have been investigated as important pathways to drastically upregulate pro-inflammatory anti-tumor immune response and are associated with anti-tumor immunity. These approaches, using synthetic agonists to activate these pathways, can be potent but delivering a localized and tumor specific activation of innate immune signaling is difficult to achieve. Methods, Results & Conclusion: Here we designed and engineered a new class of chimeric antigen receptors that couple tumor recognition with innate immune signaling, referred to as Activate, Target, Attack & Kill (ATAK™) receptors. By combining cancer recognition domains with intracellular signaling domains from innate immune receptors such as Fcg, TLR and cytokine receptors, we show that myeloid cells can be programmed to recognize cancer and elicit a broad and tunable immune response. Our data show the versatility of building ATAK receptors by harnessing innate immune pathways and support their clinical development in cell and direct in vivo therapies.
Spatial Transcriptomics: Molecular Maps of the Mammalian Brain
Annual review of neuroscience
Ortiz, C;Carlén, M;Meletis, K;
PMID: 33914592 | DOI: 10.1146/annurev-neuro-100520-082639
Maps of the nervous system inspire experiments and theories in neuroscience. Advances in molecular biology over the past decades have revolutionized the definition of cell and tissue identity. Spatial transcriptomics has opened up a new era in neuroanatomy, where the unsupervised and unbiased exploration of the molecular signatures of tissue organization will give rise to a new generation of brain maps. We propose that the molecular classification of brain regions on the basis of their gene expression profile can circumvent subjective neuroanatomical definitions and produce common reference frameworks that can incorporate cell types, connectivity, activity, and other modalities. Here we review the technological and conceptual advances made possible by spatial transcriptomics in the context of advancing neuroanatomy and discuss how molecular neuroanatomy can redefine mapping of the nervous system. Expected final online publication date for the Annual Review of Neuroscience, Volume 44 is July 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.