In-Press Preview
Articles in this category appear as authors submitted them for publication, prior to copyediting and publication layout.
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.168296.
Abstract
Given the COVID-19 pandemic, there is interest in understanding ligand-receptor features and targeted antibody-binding attributes against emerging SARS-CoV-2 variants. Here we developed a large-scale structure-based pipeline for analysis of protein-protein interactions regulating SARS-CoV-2 immune evasion. First, we generated computed structural models of the Spike protein of three SARS-CoV-2 variants (B.1.1.529, BA.2.12.1, and BA.5) bound either to a native receptor (ACE2) or to a large panel of targeted ligands (n=282), which included neutralizing or therapeutic monoclonal antibodies. Moreover, by using the Barnes Classification, we noted an overall loss of interfacial interactions (with gain-of-new-interactions in certain cases) at the receptor-binding domain (RBD) mediated by substituted residues for neutralizing complexes in Classes 1 and 2, whereas less destabilization was observed for Classes 3 and 4. Finally, an experimental validation of predicted weakened therapeutic antibody binding was performed on a cell-based assay. Compared to the original Omicron variant (B.1.1.529), derivative variants featured progressive destabilization of antibody-RBD interfaces mediated by a larger set of substituted residues, thereby providing a molecular basis for immune evasion. This approach and findings provide a framework for rapidly and efficiently generating structural models for SARS-CoV-2 variants bound to ligands of mechanistic and therapeutic value.
Authors
Joseph H. Lubin, Christopher Markosian, D. Balamurugan, Minh T. Ma, Chih-Hsiung Chen, Dongfang Liu, Renata Pasqualini, Wadih Arap, Stephen K. Burley, Sagar D. Khare
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.167546.
Abstract
BACKGROUND. A randomized clinical trial from 1984-1992 indicated that vitamin A supplementation had a beneficial effect on the progression of retinitis pigmentosa (RP), while vitamin E had an adverse effect. METHODS. Sequencing of banked DNA samples from that trial provided the opportunity to determine if certain genotypes responded preferentially to vitamin supplementation. RESULTS. The genetic solution rate was 587/765 (77%) of sequenced samples. Combining genetic solutions with electroretinogram outcomes showed that there were systematic differences in severity and progression seen among different genetic subtypes of RP, extending findings made for USH2A, RHO, RPGR, PRPF31, and EYS. Baseline electroretinogram 30Hz flicker implicit time was an independent strong predictor of progression rate. Using additional data and baseline implicit time as a predictor, the deleterious effect of vitamin E was still present. Surprisingly, the effect of vitamin A progression in the cohort as a whole was not detectable, with or without data from subsequent trials. Subgroup analyses are also discussed. CONCLUSION. Overall, genetic subtype and implicit time have significant predictive power for a patient’s rate of progression, which is useful prognostically. While vitamin E supplementation should still be avoided, these data do not support a generalized neuroprotective effect of vitamin A for all types of RP. TRAIL REGISTRATION. ClinicalTrials.gov NCT00000114, NCT00000116, NCT00346333 FUNDING. the Foundation Fighting Blindness and the National Eye Institute: RO1 EY012910 (EAP), R01 EY031036 (JC), R01EY026904 (KMB/EAP), and P30EY014104.
Authors
Jason Comander, Carol Weigel DiFranco, Kit Green Sanderson, Emily M. Place, Matthew Maher, Erin Zampaglione, Yan Zhao, Rachel M. Huckfeldt, Kinga M. Bujakowska, Eric A. Pierce
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.170181.
Abstract
Ulcerative colitis (UC), Crohn’s disease (CD), and celiac disease are prevalent intestinal inflammatory disorders with non-satisfactory therapeutic interventions. Analyzing patient data-driven cohorts can highlight disease pathways and new targets for interventions. Long non-coding RNAs (lncRNAs) are attractive candidates as they are readily targetable by RNA therapeutics, show relative cell-specific expression, and play key cellular functions. Uniformly analyzing gut mucosal transcriptomics from 696 subjects, we highlight lncRNA expression along the gastrointestinal (GI) tract, demonstrating that in control samples, lncRNAs have a more location-specific expression in comparison to protein-coding genes. We defined dysregulation of lncRNAs in treatment-naïve UC, CD, and celiac diseases using independent test and validation cohorts. Using the PROTECT inception UC cohort, we define and prioritize lncRNA linked with UC severity and prospective outcomes, and highlight lncRNAs linked with gut microbes previously implicated in mucosal homeostasis. HNF1A-AS1 lncRNA was reduced in all 3 conditions and was further reduced in more severe UC form. Similarly, the reduction of HNF1A-AS1 ortholog in mice gut epithelial showed higher sensitivity to dextran sodium sulfate-induced colitis which was coupled with alteration in the gut microbial community. These analyses highlight prioritized dysregulated lncRNAs that can guide future preclinical studies for testing them as novel potential targets.
Authors
Tzipi Braun, Katya E. Sosnovski, Amnon Amir, Marina BenShoshan, Kelli L. VanDussen, Rebekah Karns, Nina Levhar, Haya Abbas-Egbariya, Rotem Hadar, Gilat Efroni, David Castel, Camila Avivi, Michael J. Rosen, Anne M. Grifiths, Thomas D. Walters, David R. Mack, Brendan M. Boyle, Syed Asad Ali, Sean R. Moore, Melanie Schirmer, Ramnik J. Xavier, Subra Kugathasan, Anil G. Jegga, Batya Weiss, Chen Mayer, Iris Barshack, Shomron Ben-Horin, Igor Ulitsky, Anthony Beucher, Jorge Ferrer, Jeffrey S. Hyams, Lee A. Denson, Yael Haberman
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.160024.
Abstract
Intratumoral heterogeneity is a defining hallmark of glioblastoma, driving drug resistant and ultimately recurrence. Many somatic drivers of microenvironmental change have been shown to affect this heterogeneity and ultimately treatment response. However, little is known about how germline mutations effect the tumoral microenvironment. Here, we find that the single-nucleotide polymorphism (SNP) rs755622 in promoter of the cytokine macrophage migration inhibitory factor (MIF), is associated with increased leukocyte infiltration in glioblastoma. Furthermore, we identified an association between rs755622 and lactotransferrin expression, which could also be used as a biomarker for immune-infiltrated tumors. These findings demonstrate that a germline SNP in the promoter region of MIF may impact the immune microenvironment and further reveals a link between lactotransferrin and immune activation.
Authors
Tyler J. Alban, Matthew M. Grabowski, Balint Otvos, Defne Bayik, Wesley Wang, Ajay H. Zalavadia, Vladimir Makarav, Katie M. Troike, Mary McGraw, Anja Rabljenovic, Adam Lauko, Chase K.A. Neumann, Gustavo Roversi, Kristin A. Waite, Gino Cioffi, Nirav Patil, Thuy T. Tran, Kathleen McCortney, Alicia Steffens, C. Marcela Diaz-Montero, J. Mark Brown, Kathleen M. Egan, Craig Horbinski, Jill S. Barnholtz-Sloan, Prajwal Rajappa, Michael A. Vogelbaum, Richard Bucala, Timothy A. Chan, Manmeet S. Ahluwalia, Justin D. Lathia
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.166602.
Abstract
SARS-CoV-2 mRNA vaccination generates protective B cell responses targeting the SARS-CoV-2 spike glycoprotein. Whereas anti-spike memory B cell responses are long-lasting, the anti-spike humoral antibody response progressively wanes, making booster vaccinations necessary for maintaining protective immunity. Here we investigated qualitatively the plasmablast responses by measuring from single cells within hours of sampling the affinity of their secreted antibody for the SARS-CoV-2 spike receptor binding domain in cohorts of BNT162b2-vaccinated naive and COVID-19-recovered individuals. Using a unique droplet microfluidic and imaging approach, we analyzed >4,000 single IgG-secreting cells revealing high inter-individual variability in affinity for RBD with variations over 4 logs. High-affinity plasmablasts were induced by BNT162b2 vaccination against Hu-1 and Omicron RBD but disappeared quickly thereafter, whereas low-affinity plasmablasts represented >65% of the plasmablast response at all timepoints. Our droplet-based method thus proves efficient at fast and qualitative immune monitoring and should be helpful for optimization of vaccination protocols.
Authors
Matteo Broketa, Aurélien Sokal, Michael Mor, Pablo Canales-Herrerias, Angga Perima, Annalisa Meola, Ignacio Fernández, Bruno Iannascoli, Guilhem Chenon, Alexis Vandenberghe, Laetitia Languille, Marc Michel, Bertrand Godeau, Sebastien Gallien, Giovanna Melica, Marija Backovic, Felix A. Rey, Jean Baudry, Natalia T. Freund, Matthieu Mahevas, Pierre Bruhns
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.160416.
Abstract
Excessive activation of cardiac fibroblasts (CFs) in response to injury provokes cardiac fibrosis, stiffness, and failure. The local mediators counter-regulating this response remain unclear. Exogenous C-type natriuretic peptide (CNP) exerted antifibrotic effects in preclinical models. To unravel the role of the endogenous hormone, we generated mice with fibroblast-restricted deletion (KO) of guanylyl cyclase-B (GC-B), the cGMP-synthesizing CNP receptor.CNP activated GC-B/cGMP signaling in human and murine CFs, preventing proliferative and promigratory effects of AngiotensinII (AngII) and TGF-β. Fibroblast-specific GC-B-KO mice showed enhanced fibrosis in response to AngII infusions. Moreover, after two weeks of mild pressure-overload induced by transverse aortic constriction (TAC), such KO mice had augmented cardiac fibrosis and hypertrophy, together with systolic and diastolic contractile dysfunction. This was associated with increased expression of the profibrotic genes collagen I, III and periostin. Notably, such responses to AngII and TAC were greater in female as compared to male KO mice. Enhanced AngII-induced CNP expression in female hearts and augmented GC-B expression and activity in female CFs may contribute to this sex disparity. The results show that paracrine CNP signaling in CFs has antifibrotic and antihypertrophic effects. The CNP/GC-B/cGMP pathway might be a target for therapies combating pathological cardiac remodeling.
Authors
Franziska Werner, Estefania Prentki Santos, Konstanze Michel, Hanna Schrader, Katharina Völker, Tamara Potapenko, Lisa Krebes, Marco Abesser, Dorothe Möllmann, Martin Schlattjan, Hannes Schmidt, Boris V. Skryabin, Katarina Špiranec Spes, Kai Schuh, Christopher P. Denton, Hideo A. Baba, Michaela Kuhn
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.167645.
Abstract
Patients with recurrent acute pancreatitis (RAP) are at significant risk of developing early chronic pancreatitis (CP), which progresses into irreversible, end-stage CP with severe symptoms. There is no specific therapy in RAP or in early CP that may hinder disease progression. The pathogenesis of CP is complex and involves interactions among multiple cell types, including pancreatic acinar, ductal, and stellate cells (PSC). Therefore, it is pivotal to identify common pathogenic pathways in these cells that could be targeted pharmacologically. The Orai1-mediated store-operated Ca2+ entry (SOCE) is a ubiquitous signaling mechanism, which may become overactivated in pathological states resulting intracellular Ca2+ overload. In this study, we used ex vivo and in vivo preclinical disease models to demonstrate that Orai1 inhibition prevents progression of RAP and early CP. The selective Orai1 inhibitor CM5480 restored the expression of SOCE-associated regulatory factor in acinar cells, prevented uncontrolled Ca2+ elevation, protected acinar and ductal functions, mitigated immune cell infiltration, and diminished PSC activation, proliferation and migration. We suggest that the overactivation of Orai1 is a crucial pathogenetic event in the progression of early CP, and inhibition of Orai1 could prevent the development of end-stage CP.
Authors
Viktória Szabó, Noémi Csákány-Papp, Marietta Görög, Tamara Madacsy, Árpád Varga, Aletta Kiss, Balint Tel, Boldizsár Jójárt, Tim Crul, Krisztina Dudás, Mária Bagyánszki, Nikolett Bódi, Ferhan Ayaydin, Shyam Jee, Laszlo Tiszlavicz, Kenneth A. Stauderman, Sudarshan Hebbar, Petra Pallagi, József Maléth
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.169135.
Abstract
Therapeutic strategies targeting complement have revolutionized the treatment of myasthenia gravis (MG). However, a deeper understanding of complement modulation in the human system is required to improve treatment responses and identify “off-target effects” shaping long-term outcomes. For this purpose, we studied a cohort of MG patients treated with either eculizumab (n = 10) or azathioprine (n = 10) as well as treatment-naïve (n = 10) patients using a combined proteomics and metabolomics approach. This strategy confirmed known effects of eculizumab on the terminal complement cascade. Beyond that, eculizumab modulated the serum proteometabolome as distinct pathways were altered in eculizumab-treated patients including the oxidative stress response, mitogen-activated protein kinase signaling and lipid metabolism with particular emphasis on arachidonic acid signaling. We detected reduced levels of arachidonate 5-lipoxygenase (ALOX5) and leukotriene A4 (LTA4) in eculizumab-treated patients. Mechanistically, ligation of the C5a receptor (C5aR) is needed for ALOX5 metabolism and generation of downstream leukotrienes. As eculizumab prevents cleavage of C5 into C5a, decreased engagement of C5aR may inhibit ALOX5-mediated synthesis of pro-inflammatory leukotrienes. These findings indicate distinct “off-target effects” induced by eculizumab, illuminating potential mechanisms of action that may be harnessed to improve treatment outcomes.
Authors
Christopher Nelke, Christina B. Schroeter, Frauke Stascheit, Niklas Huntemann, Marc Pawlitzki, Alice G. Willison, Saskia Räuber, Nico Melzer, Ute Distler, Stefan Tenzer, Kai Stühler, Andreas Roos, Andreas Meisel, Sven G. Meuth, Tobias Ruck
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.167329.
Abstract
HIV-1 infection is characterized by a strong inflammatory environment, tissue disruption, and a progressive decline in CD4+ T cell count. Despite treatment with antiretroviral therapy (ART), the majority of persons living with HIV (PLWH) maintain residual levels of inflammation, low degree of immune activation, and higher sensitivity to cell death in their memory CD4+ T-cell compartment. To date, the mechanisms responsible for this high sensitivity remain elusive. We have identified the transcription factor IRF-5 to be involved in impairing the maintenance of murine CD4+ T cells in a chronic inflammatory environment. Here, we investigate whether IRF-5 also contributes to memory CD4+ T cell loss during HIV-1 infection. We show that TLR7 and IRF-5 were upregulated in memory CD4+ T cells from PLWH, when compared with naturally protected elite controllers and HIVfree participants. TLR7 was upstream of IRF-5, promoting Caspase 8 expression in CD4+ T cells from ART HIV-1+ but not from HIVfree participants. Moreover, IRF-5 and TLR7 expression inversely correlated with CD4+ T cell counts in primary HIV infection. Interestingly, the TLR7-IRF-5 axis acted synergistically with the Fas/FasL pathway, suggesting that TLR7 and IRF-5 expression in ART HIV-1+ memory CD4+ T cells represents an imprint that predisposes cells to Fas-mediated apoptosis. This predisposition could be blocked using IRF-5 inhibitory peptides. Thus, we propose IRF-5 blockade as a possible therapy to prevent memory CD4+ T cell loss in PLWH.
Authors
Liseth Carmona-Perez, Xavier Dagenais-Lussier, Linh Thuy Mai, Tanja Stögerer, Sharada Swaminathan, Stephane Isnard, Matthew R. Rice, Betsy J. Barnes, Jean Pierre Routy, Julien van Grevenynghe, Simona Stager
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.169860.
Abstract
While the development of different vaccines slowed the dissemination of SARS-CoV-2, the occurrence of breakthrough infections has continued to fuel the COVID-19 pandemic. To at least secure partial protection in majority of the population through one dose of a COVID-19 vaccine, delayed administration of boosters has been implemented in many countries. However, waning immunity and emergence of new variants of SARS-CoV-2 suggest that such measures may induce breakthrough infections due to intermittent lapses in protection. Optimizing vaccine dosing schedules to ensure prolonged continuity in protection could thus help control the pandemic. We developed a mechanistic model of immune response to vaccines as an in-silico tool for dosing schedule optimization. The model was calibrated with clinical datasets of acquired immunity to COVID-19 mRNA vaccines in healthy and immunocompromised subjects and showed robust validation by accurately predicting neutralizing antibody kinetics in response to multiple doses of COVID-19 mRNA vaccines. Importantly, by estimating population vulnerability to breakthrough infections, we predicted tailored vaccination dosing schedules to minimize breakthrough infections, especially for immunocompromised subjects. We identified that the optimal vaccination schedules vary from CDC-recommended dosing, suggesting that the model is a valuable tool to optimize vaccine efficacy outcomes during future outbreaks.
Authors
Prashant Dogra, Carmine Schiavone, Zhihui Wang, Javier Ruiz-Ramírez, Sergio Caserta, Daniela I. Staquicini, Christopher Markosian, Jin Wang, H. Dirk Sostman, Renata Pasqualini, Wadih Arap, Vittorio Cristini
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.170001.
Abstract
Human patients carrying genetic mutations in RNA binding motif 20 (RBM20) develop a clinically aggressive dilated cardiomyopathy (DCM). Genetic mutation knock-in (KI) animal models imply that altered function of the arginine-serine-rich (RS) domain is crucial for severe DCM. To test this hypothesis, we generated an RS domain deletion mouse model (Rbm20ΔRS). We show that Rbm20ΔRS mice manifest DCM with mis-splicing of RBM20 target transcripts. We found that RBM20 is mis-localized to the sarcoplasm in Rbm20ΔRS mice, which led to the formation of RBM20 granules similar to those detected in mutation KI animals. In contrast, mice lacking the RNA recognition motif (RRM) show similar mis-splicing of RBM20 target genes, but do not develop DCM or exhibit RBM20 granule formation. Using in vitro studies with immunocytochemical staining, we demonstrate that only DCM-associated mutations in the RS domain facilitate RBM20 nucleocytoplasmic transport and promote granule assembly. Further, we defined the core nuclear localization signal (NLS) within the RS domain. Mutation analysis of phosphorylation sites in the RS domain indicate that this modification is dispensable for RBM20 nucleocytoplasmic transport. Collectively, our findings revealed that disruption of RS domain-mediated nuclear localization is crucial for severe DCM caused by NLS mutations.
Authors
Yanghai Zhang, Zachery R. Gregorich, Yujuan Wang, Camila U. Braz, Jibin Zhang, Yang Liu, Peiheng Liu, Jiaxi Shen, Nanyumuzi Aori, Timothy A. Hacker, Henk Granzier, Wei Guo
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.134685.
Abstract
Mechanical, thermal, and chemical pain sensation is conveyed by primary nociceptors, a subset of sensory afferent neurons. The intracellular regulation of the primary nociceptive signal is an area of active study. We report here the discovery of a Gβ5-dependent regulatory pathway within mechanical nociceptors that restrains anti-nociceptive input from metabotropic GABA-B receptors. In mice with conditional knockout (cKO) of Gnb5 targeted to peripheral sensory neurons, we demonstrate the impairment of mechanical, thermal, and chemical nociception. We further report the specific loss of mechanical nociception in Rgs7-Cre+/-; Gnb5fl/fl mice but not in Rgs9-Cre+/-; Gnb5fl/fl mice, suggesting that Gβ5 might specifically regulate mechanical pain in Rgs7+ cells. Additionally, Gβ5-dependent and Rgs7-associated mechanical nociception is dependent upon GABA-B receptor signaling since both were abolished by treatment with a GABA-B receptor antagonist and since cKO of Gβ5 from sensory cells or from Rgs7+ cells potentiated the analgesic effects of GABA-B agonists. Following activation by the Mrgprd agonist β-alanine, enhanced sensitivity to inhibition by baclofen was observed in primary cultures of Rgs7+ sensory neurons harvested from Rgs7-Cre+/-; Gnb5fl/fl mice. Taken together, these results suggest that the targeted inhibition of Gβ5 function in Rgs7+ sensory neurons might provide specific relief for mechanical allodynia, including that contributing to chronic neuropathic pain, without reliance on exogenous opioids.
Authors
Mritunjay Pandey, Jian-Hua Zhang, Poorni R. Adikaram, Claire M. Kittock, Nicole Lue, Adam M. Awe, Katherine N. Degner, Nirmal Jacob, Jenna N. Staples, Rachel Thomas, Allison B. Kohnen, Sundar Ganesan, Juraj Kabat, Ching-Kang Chen, William F. Simonds
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.159141.
Abstract
Pericytes are multipotent mesenchymal precursor cells that demonstrate tissue-specific properties. In this study, by comparing human adipose and periosteal-derived pericyte microarrays, we identified TIAM1 as a key regulator of cell morphology and differentiation decisions. TIAM1 represents a tissue-specific determinant between predispositions for adipocytic versus osteoblastic differentiation in human pericytes. TIAM1 overexpression promotes an adipogenic phenotype, whereas its downregulation amplifies osteogenic differentiation. These results were replicated in vivo xenograft animal model, in which TIAM1 misexpression altered bone or adipose tissue generation in an intramuscular xenograft animal model. Changes in pericyte differentiation potential induced by TIAM1 misexpression correlated with actin organization and altered cytoskeletal morphology. Small molecule inhibitors of either Rac1 or RhoA/ROCK signaling reversed TIAM1-induced morphology and differentiation in pericytes. Finally, pericytes within calcified vessels demonstrated decreased TIAM1 expression in the diseased area compared to the healthy tissue. In summary, our results demonstrate that TIAM1 regulates the cellular morphology and differentiation potential of human pericytes, representing a molecular switch between osteogenic and adipogenic cell fates.
Authors
Ginny Ching-Yun Hsu, Yiyun Wang, Amy Z. Lu, Mario A. Gomez-Salazar, Jiajia Xu, Dongqing Li, Carolyn Meyers, Stefano Negri, Sintawat Wangsiricharoen, Kristen P. Broderick, Bruno Peault, Carol D. Morris, Aaron W. James
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.167163.
Abstract
The incidence of early onset colorectal cancer (EO-CRC) is rising and is poorly understood. Lifestyle factors and altered genetic background possibly contribute. Here we performed targeted exon sequencing of archived leukocyte DNA from 158 EO-CRC participants, which identified a missense mutation at p.A98V within the proximal DNA binding domain of Hepatic Nuclear Factor 1 alpha (HNF1AA98V, Rs1800574). The HNF1AA98V exhibited reduced DNA binding. To test function, the HNF1A variant was introduced into the mouse genome by CRISPR/Cas9 and the mice were placed on either a high fat (HFD) or high sugar diet (HSD). Only 1% of the HNF1A mutant mice developed polyps on normal chow; however,19% and 3% developed polyps on the HFD and HSD, respectively. RNA-Seq revealed an increase in metabolic, immune, lipid biogenesis genes and Wnt/β-catenin signaling components in the HNF1A mutant relative to the wildtype mice. Mouse polyps and colon cancers from subjects carrying the HNF1AA98V variant exhibited reduced CDX2 and elevated β-catenin proteins. We further demonstrated decreased occupancy of HNF1AA98V at the Cdx2 locus and reduced Cdx2 promoter activity compared to wildtype HNF1A. Collectively, our study shows that the HNF1AA98V variant plus HFD promotes the formation of colonic polyps by activating β-catenin via decreasing Cdx2 expression.
Authors
Heyu Song, Ricky A. Sontz, Matthew J. Vance, Julia M. Morris, Sulaiman Sheriff, Songli Zhu, Suzann Duan, Jiping Zeng, Erika Koeppe, Ritu Pandey, Curtis A. Thorne, Elena M. Stoffel, Juanita L. Merchant
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.161874.
Abstract
Inflammatory bowel disease (IBD) is a relapsing-remitting disorder characterized by chronic inflammation of the gastrointestinal (GI) tract. Anxiety symptoms are commonly observed in IBD patients, but the mechanistic link between IBD and anxiety remains elusive. Here, we sought to characterize gut-to-brain signaling and brain circuitry responsible for the pathological expression of anxiety-like behaviors in male dextran sulfate sodium (DSS)-induced experimental colitis mice. We found that DSS-treated mice displayed increased anxiety-like behaviors, which were prevented by bilateral GI vagal afferent ablation. The locus coeruleus (LC) is a relay center connecting the nucleus tractus solitarius to the basolateral amygdala (BLA) in controlling anxiety-like behaviors. Chemogenetic silencing of noradrenergic LC projections to the BLA reduced anxiety-like behaviors in DSS-treated mice. This work expands our understanding of the neural mechanisms by which IBD leads to comorbid anxiety and emphasizes a critical role of gastric vagal afferent signaling in gut-to-brain regulation of emotional states.
Authors
Chin-Hao Chen, Tsung-Chih Tsai, Yi-Jen Wu, Kuei-Sen Hsu
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.161675.
Abstract
Tumor vascular normalization prevents tumor cells from breaking through the basement membrane and entering the vasculature, and then inhibiting metastasis initiation. In this study, we reported that the anti-tumor peptide JP1 regulates the mitochondria metabolic reprogramming through AMPK/FOXO3a/UQCRC2 signaling, which improves the tumor microenvironment hypoxia. The oxygen-rich tumor microenvironment inhibits the secretion of interleukin-8 (IL8) by tumor cells, thereby promoting tumor vascular normalization. The normalized vasculature results in mature and regular blood vessels, which makes the tumor microenvironment form benign feedback of vascular normalization, sufficient perfusion, and oxygen-rich microenvironment, prevents tumor cells from entering the vasculature and inhibits metastasis initiation. Moreover, the combined therapy of JP1 and paclitaxel (PTX) maintain a certain vascular density in the tumor, as well as promoting tumor vascular normalization, increasing the delivery of oxygen and drugs, and enhancing the anti-tumor effect. Collectively, our work highlighted a novel anti-tumor peptide JP1 to inhibit metastasis initiation and its mechanism of action.
Authors
Jiahua Cui, Zhen Che, Lu Zou, Dongyin Chen, Zhan Xie, Kun Ding, Huning Jiang, Aiping Li, Jianwei Zhou, Yongqian Shu
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.170671.
Abstract
Growing evidence indicates that the glucagon-like-peptide-1 (GLP-1) system is involved in the neurobiology of addictive behaviors and GLP-1 analogues may be used for the treatment of alcohol use disorder (AUD). Semaglutide is a long-acting GLP-1 analogue with compelling characteristics for clinical translation. The goal of this study was to examine the effects of semaglutide on biobehavioral correlates of alcohol use in rodents, using psychopharmacology and electrophysiology experiments. A drinking-in-the-dark procedure was used to test the effects of semaglutide on binge-like drinking in male and female mice. We also tested the effects of semaglutide on both binge-like and dependence-induced alcohol drinking in male and female rats. Finally, the acute effects of semaglutide on GABA neurotransmission were examined by recording spontaneous inhibitory postsynaptic currents (sIPSCs) from central nucleus of the amygdala (CeA) and infralimbic cortex (ILC) neurons. Results showed that semaglutide dose-dependently reduced binge-like alcohol drinking in mice; a similar effect was observed on the intake of other caloric/non-caloric solutions. Semaglutide also reduced binge-like and dependence-induced alcohol drinking in rats. In alcohol-naïve rats, an acute application of semaglutide increased sIPSC frequency in CeA and ILC neurons, suggesting enhanced GABA release, while in alcohol-dependent rats, semaglutide did not significantly alter overall CeA and ILC GABA transmission. In conclusion, the GLP-1 analogue semaglutide decreased alcohol intake across different drinking models and species and modulated central GABA neurotransmission in rodents, providing support for clinical testing of semaglutide as a potential novel pharmacotherapy for AUD.
Authors
Vicky Chuong, Mehdi Farokhnia, Sophia Khom, Claire L. Pince, Sophie K. Elvig, Roman Vlkolinsky, Renata C.N. Marchette, George F. Koob, Marisa Roberto, Leandro F. Vendruscolo, Lorenzo Leggio
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.166270.
Abstract
Synaptic plasticity impairment plays a critical role in the pathogenesis of Alzheimer’s disease (AD), and emerging evidence has shown that microRNAs (miRNAs) are alternative biomarkers and therapeutic targets for synaptic dysfunctions in AD. In this study, we found that the level of miR-431 was downregulated in the plasma of amnestic mild cognitive impairment (aMCI) and AD patients. In addition, it was decreased in the hippocampus and plasma of APPswe/PS1dE9 (APP/PS1) mice. Lentivirus mediated miR-431 overexpression in the hippocampus CA1 ameliorated synaptic plasticity and memory deficits of APP/PS1 mice, while it didn't affect the Aβ levels. Smad4 was identified as a target of miR-431, and Smad4 knockdown modulated the expression of synaptic proteins including SAP102, and protected against synaptic plasticity and memory dysfunctions in APP/PS1 mice. Furthermore, Smad4 overexpression reversed the protective effects of miR-431, indicating that miR-431 attenuated synaptic impairment at least partially by Smad4 inhibition. Thus, these results indicated that miR-431/Smad4 might be a potential therapeutic target for AD treatment.
Authors
Jianwei Ge, Zhiwei Xue, Shu Shu, Linjie Yu, Ruomeng Qin, Wenyuan Tao, Pinyi Liu, Xiaohong Dong, Zhen Lan, Xinyu Bao, Lei Ye, Yun Xu, Xiaolei Zhu
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.162995.
Abstract
Progesterone (P4) is essential for embryo implantation, but the extent to which the pro-gestational effects of P4 depend on the maternal immune compartment is unknown. Here, we investigate whether regulatory T cells (Treg cells) act to mediate luteal phase P4 effects on uterine receptivity in mice. P4 antagonist RU486 administered to mice on days 0.5 and 2.5 post coitum (dpc) to model luteal phase P4 deficiency caused fewer CD4+Foxp3+ Treg cells and impaired Treg functional competence, along with dysfunctional uterine vascular remodeling and perturbed placental development in mid-gestation. These effects were linked with fetal loss and fetal growth restriction, accompanied by a Th1/CD8-skewed T cell profile. Adoptive transfer at implantation of Treg cells - but not T conventional (Tconv) cells – alleviated fetal loss and fetal growth restriction by mitigating adverse effects of reduced P4 signaling on uterine blood vessel remodeling and placental structure, and restoring maternal T cell imbalance. These findings demonstrate an essential role for Treg cells in mediating P4 effects at implantation, and indicate that Treg cells are a sensitive and critical effector mechanism through which P4 drives uterine receptivity to support robust placental development and fetal growth.
Authors
Ella S. Green, Lachlan M. Moldenhauer, Holly M. Groome, David J. Sharkey, Peck Y. Chin, Alison S. Care, Rebecca L. Robker, Shaun R. McColl, Sarah A. Robertson
Citation Information: JCI Insight. 2023. https://doi.org/10.1172/jci.insight.160652.
Abstract
Radiographic contact of glioblastoma (GBM) tumors with the lateral ventricle and adjacent stem cell niche correlates with poor patient prognosis, but the cellular basis of this difference is unclear. Here, we reveal and functionally characterize distinct immune microenvironments that predominate in subtypes of GBM distinguished by proximity to the lateral ventricle. Mass cytometry analysis of IDH-wildtype human tumors identified elevated T cell checkpoint receptor expression and greater abundance of a specific CD32+CD44+HLA-DRhigh macrophage population in ventricle-contacting GBM. Multiple computational analysis approaches, phospho-specific cytometry, and focal resection of GBMs confirmed and extended these findings. Phospho-flow quantified cytokine-induced immune cell signaling in ventricle-contacting GBM revealing differential signaling between GBM subtypes. Subregion analysis within a given tumor supported initial findings and revealed intratumoral compartmentalization of T cell memory and exhaustion phenotypes within GBM subtypes. Collectively, these results characterize immunotherapeutically targetable features of macrophages and suppressed lymphocytes in glioblastomas defined by MRI-detectable lateral ventricle contact.
Authors
Todd Bartkowiak, Sierra M. Lima, Madeline J. Hayes, Akshitkumar M. Mistry, Asa A. Brockman, Justine Sinnaeve, Nalin Leelatian, Caroline E. Roe, Bret C. Mobley, Silky Chotai, Kyle D. Weaver, Reid C. Thompson, Lola B. Chambless, Rebecca A. Ihrie, Jonathan M. Irish
