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Chang KR, Tsao DD, Bennett C, Wang E, Floyd JF, Tay ASY, Greenwald E, Kim ES, Griffin C, Morse E, Chisholm T, Rankin AE, Baena-Lopez LA, Lantz N, Fox E, Kockel L, Kim SK, Park S. Transgenic Drosophila lines for LexA-dependent gene and growth regulation. G3 (BETHESDA, MD.) 2022; 12:jkac018. [PMID: 35100369 PMCID: PMC8895989 DOI: 10.1093/g3journal/jkac018] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 01/05/2022] [Indexed: 11/12/2022]
Abstract
Conditional expression of short hairpin RNAs with binary genetic systems is an indispensable tool for studying gene function. Addressing mechanisms underlying cell-cell communication in vivo benefits from simultaneous use of 2 independent gene expression systems. To complement the abundance of existing Gal4/UAS-based resources in Drosophila, we and others have developed LexA/LexAop-based genetic tools. Here, we describe experimental and pedagogical advances that promote the efficient conversion of Drosophila Gal4 lines to LexA lines, and the generation of LexAop-short hairpin RNA lines to suppress gene function. We developed a CRISPR/Cas9-based knock-in system to replace Gal4 coding sequences with LexA, and a LexAop-based short hairpin RNA expression vector to achieve short hairpin RNA-mediated gene silencing. We demonstrate the use of these approaches to achieve targeted genetic loss-of-function in multiple tissues. We also detail our development of secondary school curricula that enable students to create transgenic flies, thereby magnifying the production of well-characterized LexA/LexAop lines for the scientific community. The genetic tools and teaching methods presented here provide LexA/LexAop resources that complement existing resources to study intercellular communication coordinating metazoan physiology and development.
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Li H, Janssens J, De Waegeneer M, Kolluru SS, Davie K, Gardeux V, Saelens W, David F, Brbić M, Spanier K, Leskovec J, McLaughlin CN, Xie Q, Jones RC, Brueckner K, Shim J, Tattikota SG, Schnorrer F, Rust K, Nystul TG, Carvalho-Santos Z, Ribeiro C, Pal S, Mahadevaraju S, Przytycka TM, Allen AM, Goodwin SF, Berry CW, Fuller MT, White-Cooper H, Matunis EL, DiNardo S, Galenza A, O’Brien LE, Dow JAT, Jasper H, Oliver B, Perrimon N, Deplancke B, Quake SR, Luo L, Aerts S, Agarwal D, Ahmed-Braimah Y, Arbeitman M, Ariss MM, Augsburger J, Ayush K, Baker CC, Banisch T, Birker K, Bodmer R, Bolival B, Brantley SE, Brill JA, Brown NC, Buehner NA, Cai XT, Cardoso-Figueiredo R, Casares F, Chang A, Clandinin TR, Crasta S, Desplan C, Detweiler AM, Dhakan DB, Donà E, Engert S, Floc'hlay S, George N, González-Segarra AJ, Groves AK, Gumbin S, Guo Y, Harris DE, Heifetz Y, Holtz SL, Horns F, Hudry B, Hung RJ, Jan YN, Jaszczak JS, Jefferis GSXE, Karkanias J, Karr TL, Katheder NS, Kezos J, Kim AA, Kim SK, Kockel L, Konstantinides N, Kornberg TB, Krause HM, Labott AT, Laturney M, Lehmann R, Leinwand S, Li J, Li JSS, Li K, Li K, Li L, Li T, Litovchenko M, Liu HH, Liu Y, Lu TC, Manning J, Mase A, Matera-Vatnick M, Matias NR, McDonough-Goldstein CE, McGeever A, McLachlan AD, Moreno-Roman P, Neff N, Neville M, Ngo S, Nielsen T, O'Brien CE, Osumi-Sutherland D, Özel MN, Papatheodorou I, Petkovic M, Pilgrim C, Pisco AO, Reisenman C, Sanders EN, Dos Santos G, Scott K, Sherlekar A, Shiu P, Sims D, Sit RV, Slaidina M, Smith HE, Sterne G, Su YH, Sutton D, Tamayo M, Tan M, Tastekin I, Treiber C, Vacek D, Vogler G, Waddell S, Wang W, Wilson RI, Wolfner MF, Wong YCE, Xie A, Xu J, Yamamoto S, Yan J, Yao Z, Yoda K, Zhu R, Zinzen RP. Fly Cell Atlas: A single-nucleus transcriptomic atlas of the adult fruit fly. Science 2022; 375:eabk2432. [PMID: 35239393 PMCID: PMC8944923 DOI: 10.1126/science.abk2432] [Citation(s) in RCA: 239] [Impact Index Per Article: 119.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
For more than 100 years, the fruit fly Drosophila melanogaster has been one of the most studied model organisms. Here, we present a single-cell atlas of the adult fly, Tabula Drosophilae, that includes 580,000 nuclei from 15 individually dissected sexed tissues as well as the entire head and body, annotated to >250 distinct cell types. We provide an in-depth analysis of cell type-related gene signatures and transcription factor markers, as well as sexual dimorphism, across the whole animal. Analysis of common cell types between tissues, such as blood and muscle cells, reveals rare cell types and tissue-specific subtypes. This atlas provides a valuable resource for the Drosophila community and serves as a reference to study genetic perturbations and disease models at single-cell resolution.
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Dai XQ, Camunas-Soler J, Briant LJB, Dos Santos T, Spigelman AF, Walker EM, Arrojo E Drigo R, Bautista A, Jones RC, Avrahami D, Lyon J, Nie A, Smith N, Zhang Y, Johnson J, Manning Fox JE, Michelakis ED, Light PE, Kaestner KH, Kim SK, Rorsman P, Stein RW, Quake SR, MacDonald PE. Heterogenous impairment of α cell function in type 2 diabetes is linked to cell maturation state. Cell Metab 2022; 34:256-268.e5. [PMID: 35108513 PMCID: PMC8852281 DOI: 10.1016/j.cmet.2021.12.021] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 10/08/2021] [Accepted: 12/22/2021] [Indexed: 02/03/2023]
Abstract
In diabetes, glucagon secretion from pancreatic α cells is dysregulated. The underlying mechanisms, and whether dysfunction occurs uniformly among cells, remain unclear. We examined α cells from human donors and mice using electrophysiological, transcriptomic, and computational approaches. Rising glucose suppresses α cell exocytosis by reducing P/Q-type Ca2+ channel activity, and this is disrupted in type 2 diabetes (T2D). Upon high-fat feeding of mice, α cells shift toward a "β cell-like" electrophysiological profile in concert with indications of impaired identity. In human α cells we identified links between cell membrane properties and cell surface signaling receptors, mitochondrial respiratory chain complex assembly, and cell maturation. Cell-type classification using machine learning of electrophysiology data demonstrated a heterogenous loss of "electrophysiologic identity" in α cells from donors with type 2 diabetes. Indeed, a subset of α cells with impaired exocytosis is defined by an enrichment in progenitor and lineage markers and upregulation of an immature transcriptomic phenotype, suggesting important links between α cell maturation state and dysfunction.
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Marquez-Curtis LA, Dai XQ, Hang Y, Lam JY, Lyon J, Manning Fox JE, McGann LE, MacDonald PE, Kim SK, Elliott JAW. Cryopreservation and post-thaw characterization of dissociated human islet cells. PLoS One 2022; 17:e0263005. [PMID: 35081145 PMCID: PMC8791532 DOI: 10.1371/journal.pone.0263005] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 01/06/2022] [Indexed: 12/22/2022] Open
Abstract
The objective of this study is to optimize the cryopreservation of dissociated islet cells and obtain functional cells that can be used in single-cell transcriptome studies on the pathology and treatment of diabetes. Using an iterative graded freezing approach we obtained viable cells after cooling in 10% dimethyl sulfoxide and 6% hydroxyethyl starch at 1°C/min to -40°C, storage in liquid nitrogen, rapid thaw, and removal of cryoprotectants by serial dilution. The expression of epithelial cell adhesion molecule declined immediately after thaw, but recovered after overnight incubation, while that of an endocrine cell marker (HPi2) remained high after cryopreservation. Patch-clamp electrophysiology revealed differences in channel activities and exocytosis of various islet cell types; however, exocytotic responses, and the biophysical properties of voltage-gated Na+ and Ca2+ channels, are sustained after cryopreservation. Single-cell RNA sequencing indicates that overall transcriptome and crucial exocytosis genes are comparable between fresh and cryopreserved dispersed human islet cells. Thus, we report an optimized procedure for cryopreserving dispersed islet cells that maintained their membrane integrity, along with their molecular and functional phenotypes. Our findings will not only provide a ready source of cells for investigating cellular mechanisms in diabetes but also for bio-engineering pseudo-islets and islet sheets for modeling studies and potential transplant applications.
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Wu CT, Hilgendorf KI, Bevacqua RJ, Hang Y, Demeter J, Kim SK, Jackson PK. Discovery of ciliary G protein-coupled receptors regulating pancreatic islet insulin and glucagon secretion. Genes Dev 2021; 35:1243-1255. [PMID: 34385262 PMCID: PMC8415323 DOI: 10.1101/gad.348261.121] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Accepted: 07/02/2021] [Indexed: 01/17/2023]
Abstract
Multiple G protein-coupled receptors (GPCRs) are expressed in pancreatic islet cells, but the majority have unknown functions. We observed specific GPCRs localized to primary cilia, a prominent signaling organelle, in pancreatic α and β cells. Loss of cilia disrupts β-cell endocrine function, but the molecular drivers are unknown. Using functional expression, we identified multiple GPCRs localized to cilia in mouse and human islet α and β cells, including FFAR4, PTGER4, ADRB2, KISS1R, and P2RY14. Free fatty acid receptor 4 (FFAR4) and prostaglandin E receptor 4 (PTGER4) agonists stimulate ciliary cAMP signaling and promote glucagon and insulin secretion by α- and β-cell lines and by mouse and human islets. Transport of GPCRs to primary cilia requires TULP3, whose knockdown in primary human and mouse islets relocalized ciliary FFAR4 and PTGER4 and impaired regulated glucagon or insulin secretion, without affecting ciliary structure. Our findings provide index evidence that regulated hormone secretion by islet α and β cells is controlled by ciliary GPCRs providing new targets for diabetes.
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Kaestner KH, Campbell-Thompson M, Dor Y, Gill RG, Glaser B, Kim SK, Sander M, Stabler C, Stewart AF, Powers AC. What is a β cell? - Chapter I in the Human Islet Research Network (HIRN) review series. Mol Metab 2021; 53:101323. [PMID: 34416394 PMCID: PMC8452767 DOI: 10.1016/j.molmet.2021.101323] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 08/03/2021] [Accepted: 08/12/2021] [Indexed: 12/01/2022] Open
Abstract
Background The pancreatic β cell, as the sole source of the vital hormone insulin, has been under intensive study for more than a century. Given the potential of newly created insulin-producing cells as a treatment or even cure of type 1 diabetes (T1D) and possibly in severe cases of type 2 diabetes (T2D), multiple academic and commercial laboratories are working to derive surrogate glucose-responsive, insulin-producing cells. Scope of Review The recent development of advanced phenotyping technologies, including molecular, epigenomic, histological, or functional, have greatly improved our understanding of the critical properties of human β cells. Using this information, here we summarize the salient features of normal, fully functional adult human β cells, and propose minimal criteria for what should rightfully be termed ‘β cells’ as opposed to insulin-producing but not fully-functional surrogates that we propose should be referred to as ‘β-like’ cells or insulin-producing cells. Major Conclusions Clear criteria can be established to differentiate fully functional, mature β cells from ‘β-like’ surrogates. In addition, we outline important knowledge gaps that must be addressed to enable a greater understanding of the β cell.
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Kim SK, Tsao DD, Suh GSB, Miguel-Aliaga I. Discovering signaling mechanisms governing metabolism and metabolic diseases with Drosophila. Cell Metab 2021; 33:1279-1292. [PMID: 34139200 PMCID: PMC8612010 DOI: 10.1016/j.cmet.2021.05.018] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 04/30/2021] [Accepted: 05/25/2021] [Indexed: 12/18/2022]
Abstract
There has been rapid growth in the use of Drosophila and other invertebrate systems to dissect mechanisms governing metabolism. New assays and approaches to physiology have aligned with superlative genetic tools in fruit flies to provide a powerful platform for posing new questions, or dissecting classical problems in metabolism and disease genetics. In multiple examples, these discoveries exploit experimental advantages as-yet unavailable in mammalian systems. Here, we illustrate how fly studies have addressed long-standing questions in three broad areas-inter-organ signaling through hormonal or neural mechanisms governing metabolism, intestinal interoception and feeding, and the cellular and signaling basis of sexually dimorphic metabolism and physiology-and how these findings relate to human (patho)physiology. The imaginative application of integrative physiology and related approaches in flies to questions in metabolism is expanding, and will be an engine of discovery, revealing paradigmatic features of metabolism underlying human diseases and physiological equipoise in health.
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Menon DP, Qi G, Kim SK, Moss ME, Penumatsa KC, Warburton RR, Toksoz D, Wilson J, Hill NS, Jaffe IZ, Preston IR. Vascular cell-specific roles of mineralocorticoid receptors in pulmonary hypertension. Pulm Circ 2021; 11:20458940211025240. [PMID: 34211700 PMCID: PMC8216367 DOI: 10.1177/20458940211025240] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 05/13/2021] [Indexed: 12/18/2022] Open
Abstract
Abnormalities that characterize pulmonary arterial hypertension include impairment in the structure and function of pulmonary vascular endothelial and smooth muscle cells. Aldosterone levels are elevated in human pulmonary arterial hypertension and in experimental pulmonary hypertension, while inhibition of the aldosterone-binding mineralocorticoid receptor attenuates pulmonary hypertension in multiple animal models. We explored the role of mineralocorticoid receptor in endothelial and smooth muscle cells in using cell-specific mineralocorticoid receptor knockout mice exposed to sugen/hypoxia-induced pulmonary hypertension. Treatment with the mineralocorticoid receptor inhibitor spironolactone significantly reduced right ventricular systolic pressure. However, this is not reproduced by selective mineralocorticoid receptor deletion in smooth muscle cells or endothelial cells. Similarly, spironolactone attenuated the increase in right ventricular cardiomyocyte area independent of vascular mineralocorticoid receptor with no effect on right ventricular weight or interstitial fibrosis. Right ventricular perivascular fibrosis was significantly decreased by spironolactone and this was reproduced by specific deletion of mineralocorticoid receptor from endothelial cells. Endothelial cell-mineralocorticoid receptor deletion attenuated the sugen/hypoxia-induced increase in the leukocyte-adhesion molecule, E-selectin, and collagen IIIA1 in the right ventricle. Spironolactone also significantly reduced pulmonary arteriolar muscularization, independent of endothelial cell-mineralocorticoid receptor or smooth muscle cell-mineralocorticoid receptor. Finally, the degree of pulmonary perivascular inflammation was attenuated by mineralocorticoid receptor antagonism and was fully reproduced by smooth muscle cell-specific mineralocorticoid receptor deletion. These studies demonstrate that in the sugen/hypoxia pulmonary hypertension model, systemic-mineralocorticoid receptor blockade significantly attenuates the disease and that mineralocorticoid receptor has cell-specific effects, with endothelial cell-mineralocorticoid receptor contributing to right ventricular perivascular fibrosis and smooth muscle cell-mineralocorticoid receptor participating in pulmonary vascular inflammation. As mineralocorticoid receptor antagonists are being investigated to treat pulmonary arterial hypertension, these findings support novel mechanisms and potential mineralocorticoid receptor targets that mediate therapeutic benefits in patients.
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Moon JH, Kim H, Kim H, Park J, Choi W, Choi W, Hong HJ, Ro HJ, Jun S, Choi SH, Banerjee RR, Shong M, Cho NH, Kim SK, German MS, Jang HC, Kim H. Lactation improves pancreatic β cell mass and function through serotonin production. Sci Transl Med 2021; 12:12/541/eaay0455. [PMID: 32350130 DOI: 10.1126/scitranslmed.aay0455] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 12/23/2019] [Accepted: 03/04/2020] [Indexed: 12/18/2022]
Abstract
Pregnancy imposes a substantial metabolic burden on women through weight gain and insulin resistance. Lactation reduces the risk of maternal postpartum diabetes, but the mechanisms underlying this benefit are unknown. Here, we identified long-term beneficial effects of lactation on β cell function, which last for years after the cessation of lactation. We analyzed metabolic phenotypes including β cell characteristics in lactating and non-lactating humans and mice. Lactating and non-lactating women showed comparable glucose tolerance at 2 months after delivery, but after a mean of 3.6 years, glucose tolerance in lactated women had improved compared to non-lactated women. In humans, the disposition index, a measure of insulin secretory function of β cells considering the degree of insulin sensitivity, was higher in lactated women at 3.6 years after delivery. In mice, lactation improved glucose tolerance and increased β cell mass at 3 weeks after delivery. Amelioration of glucose tolerance and insulin secretion were maintained up to 4 months after delivery in lactated mice. During lactation, prolactin induced serotonin production in β cells. Secreted serotonin stimulated β cell proliferation through serotonin receptor 2B in an autocrine and paracrine manner. In addition, intracellular serotonin acted as an antioxidant to mitigate oxidative stress and improved β cell survival. Together, our results suggest that serotonin mediates the long-term beneficial effects of lactation on female metabolic health by increasing β cell proliferation and reducing oxidative stress in β cells.
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Kim SK, Park MW, Min C, Park IS, Park B, Byun SH, Choi HG, Hong SJ. Increased risk of chronic otitis media in chronic rhinosinusitis patients: a longitudinal follow-up study using a national health screening cohort. Rhinology 2021; 59:292-300. [PMID: 33315021 DOI: 10.4193/rhin20.363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Chronic rhinosinusitis (CRS) and chronic otitis media (COM) share pathophysiological mechanisms such as bacterial infection, biofilm, and persistence of the obstruction state of ventilation routes. However, only a few studies have investigated the relationship between these two diseases nationwide and in the general population. The purpose of this study was to determine whether the incidence of COM in patients with CRS differed from that of a matched control from the national health screening cohort. METHODS Data from the Korean Health Insurance Review and Assessment Service-National Patient Samples were collected from 2002 to 2015. Participants who were treated ≥ ≥ ≥2 times and underwent head and neck computed tomography evaluation were selected. A 1:4 matched CRS group (n=8,057) and a control group (n=32,228) were selected. The control group included participants who were never treated with the ICD-10 code J32 from 2002 to 2015. The CRS group included CRS patients with/without nasal polyps. RESULTS The incidence of COM was significantly higher in the CRS group than in the control group. In a subgroup analysis, the incidence of COM in all age groups and in men and women was significantly higher in the CRS group than in the control group. More, CRS increased the risk of COM. CONCLUSIONS A significant association was observed between CRS and COM. This indicates that CRS patients have a high risk of developing COM.
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Yi SW, Kim YM, Won YJ, Kim SK, Kim SH. Association between body mass index and the risk of falls: a nationwide population-based study. Osteoporos Int 2021; 32:1071-1078. [PMID: 33411009 DOI: 10.1007/s00198-020-05725-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 10/29/2020] [Indexed: 10/22/2022]
Abstract
UNLABELLED The association of BMI with falls differed between men and women in Korea. Obesity was associated with a greater risk of falls in women, whereas underweight seemed to increase the risk of falls compared with normal weight in men. PURPOSE This study examined the sex-specific association between body mass index (BMI) and falls in Korean adults using data from a large population-based survey. METHODS We analyzed 113,805 men and women (age ≥ 50 years) who participated in the Korean Community Health Survey in 2013. Logistic regression was used to assess the relationship between BMI and falls. RESULTS The mean (± standard deviation) age and BMI of all participants were 63.8 ± 9.6 years and 23.2 ± 2.9 kg/m2, respectively. Among the 113,805 subjects, 19.1% and 6.7% had histories of falls and recurrent falls, respectively. The association of BMI with recurrent falls differed between men and women. The multivariable-adjusted odd ratios (ORs) for recurrent falls were 0.98 (95% confidence interval [CI] 0.86-1.12), 1.23 (1.14-1.32), and 1.51 (1.26-1.81) in women with BMIs of < 18.5, 25-29.9, and ≥ 30 kg/m2, respectively, relative to those with BMIs of 18.5-24.9 kg/m2. The corresponding ORs for men were 1.20 (95% CI 1.01-1.42), 1.05 (0.96-1.14), and 0.97 (0.69-1.38), respectively. Older age and low economic level were associated independently with higher ORs of recurrent falls in men and women, respectively. In addition, comorbidities, including diabetes, stroke, arthritis, osteoporosis, and asthma, correlated significantly with an increased risk of recurrent falls (all p < 0.001). CONCLUSIONS Obesity was associated with a greater risk of recurrent falls in women, whereas underweight seemed to be associated with a greater risk of falls in men.
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Friedlander MSH, Nguyen VM, Kim SK, Bevacqua RJ. Pancreatic Pseudoislets: An Organoid Archetype for Metabolism Research. Diabetes 2021; 70:1051-1060. [PMID: 33947722 PMCID: PMC8343609 DOI: 10.2337/db20-1115] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 02/20/2021] [Indexed: 01/08/2023]
Abstract
Pancreatic islets are vital endocrine regulators of systemic metabolism, and recent investigations have increasingly focused on understanding human islet biology. Studies of isolated human islets have advanced understanding of the development, function, and regulation of cells comprising islets, especially pancreatic α- and β-cells. However, the multicellularity of the intact islet has stymied specific experimental approaches-particularly in genetics and cell signaling interrogation. This barrier has been circumvented by the observation that islet cells can survive dispersion and reaggregate to form "pseudoislets," organoids that retain crucial physiological functions, including regulated insulin and glucagon secretion. Recently, exciting advances in the use of pseudoislets for genetics, genomics, islet cell transplantation, and studies of intraislet signaling and islet cell interactions have been reported by investigators worldwide. Here we review molecular and cellular mechanisms thought to promote islet cell reaggregation, summarize methods that optimize pseudoislet development, and detail recent insights about human islet biology from genetic and transplantation-based pseudoislet experiments. Owing to robust, international programs for procuring primary human pancreata, pseudoislets should serve as both a durable paradigm for primary organoid studies and as an engine of discovery for islet biology, diabetes, and metabolism research.
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Bevacqua RJ, Dai X, Lam JY, Gu X, Friedlander MSH, Tellez K, Miguel-Escalada I, Bonàs-Guarch S, Atla G, Zhao W, Kim SH, Dominguez AA, Qi LS, Ferrer J, MacDonald PE, Kim SK. CRISPR-based genome editing in primary human pancreatic islet cells. Nat Commun 2021; 12:2397. [PMID: 33893274 PMCID: PMC8065166 DOI: 10.1038/s41467-021-22651-w] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 03/22/2021] [Indexed: 02/02/2023] Open
Abstract
Gene targeting studies in primary human islets could advance our understanding of mechanisms driving diabetes pathogenesis. Here, we demonstrate successful genome editing in primary human islets using clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein 9 (Cas9). CRISPR-based targeting efficiently mutated protein-coding exons, resulting in acute loss of islet β-cell regulators, like the transcription factor PDX1 and the KATP channel subunit KIR6.2, accompanied by impaired β-cell regulation and function. CRISPR targeting of non-coding DNA harboring type 2 diabetes (T2D) risk variants revealed changes in ABCC8, SIX2 and SIX3 expression, and impaired β-cell function, thereby linking regulatory elements in these target genes to T2D genetic susceptibility. Advances here establish a paradigm for genetic studies in human islet cells, and reveal regulatory and genetic mechanisms linking non-coding variants to human diabetes risk.
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Tosti L, Hang Y, Debnath O, Tiesmeyer S, Trefzer T, Steiger K, Ten FW, Lukassen S, Ballke S, Kühl AA, Spieckermann S, Bottino R, Ishaque N, Weichert W, Kim SK, Eils R, Conrad C. Single-Nucleus and In Situ RNA-Sequencing Reveal Cell Topographies in the Human Pancreas. Gastroenterology 2021; 160:1330-1344.e11. [PMID: 33212097 DOI: 10.1053/j.gastro.2020.11.010] [Citation(s) in RCA: 96] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 10/30/2020] [Accepted: 11/03/2020] [Indexed: 12/15/2022]
Abstract
BACKGROUND & AIMS Molecular evidence of cellular heterogeneity in the human exocrine pancreas has not been yet established because of the local concentration and cascade of hydrolytic enzymes that can rapidly degrade cells and RNA upon pancreatic resection. We sought to better understand the heterogeneity and cellular composition of the pancreas in neonates and adults in healthy and diseased conditions using single-cell sequencing approaches. METHODS We innovated single-nucleus RNA-sequencing protocols and profiled more than 120,000 cells from pancreata of adult and neonatal human donors. We validated the single-nucleus findings using RNA fluorescence in situ hybridization, in situ sequencing, and computational approaches. RESULTS We created the first comprehensive atlas of human pancreas cells including epithelial and nonepithelial constituents, and uncovered 3 distinct acinar cell types, with possible implications for homeostatic and inflammatory processes of the pancreas. The comparison with neonatal single-nucleus sequencing data showed a different cellular composition of the endocrine tissue, highlighting the tissue dynamics occurring during development. By applying spatial cartography, involving cell proximity mapping through in situ sequencing, we found evidence of specific cell type neighborhoods, dynamic topographies in the endocrine and exocrine pancreas, and principles of morphologic organization of the organ. Furthermore, similar analyses in chronic pancreatitis biopsy samples showed the presence of acinar-REG+ cells, a reciprocal association between macrophages and activated stellate cells, and a new potential role of tuft cells in this disease. CONCLUSIONS Our human pancreas cell atlas can be interrogated to understand pancreatic cell biology and provides a crucial reference set for comparisons with diseased tissue samples to map the cellular foundations of pancreatic diseases.
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Bevacqua RJ, Lam JY, Peiris H, Whitener RL, Kim S, Gu X, Friedlander MSH, Kim SK. SIX2 and SIX3 coordinately regulate functional maturity and fate of human pancreatic β cells. Genes Dev 2021; 35:234-249. [PMID: 33446570 PMCID: PMC7849364 DOI: 10.1101/gad.342378.120] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 12/08/2020] [Indexed: 12/16/2022]
Abstract
The physiological functions of many vital tissues and organs continue to mature after birth, but the genetic mechanisms governing this postnatal maturation remain an unsolved mystery. Human pancreatic β cells produce and secrete insulin in response to physiological cues like glucose, and these hallmark functions improve in the years after birth. This coincides with expression of the transcription factors SIX2 and SIX3, whose functions in native human β cells remain unknown. Here, we show that shRNA-mediated SIX2 or SIX3 suppression in human pancreatic adult islets impairs insulin secretion. However, transcriptome studies revealed that SIX2 and SIX3 regulate distinct targets. Loss of SIX2 markedly impaired expression of genes governing β-cell insulin processing and output, glucose sensing, and electrophysiology, while SIX3 loss led to inappropriate expression of genes normally expressed in fetal β cells, adult α cells, and other non-β cells. Chromatin accessibility studies identified genes directly regulated by SIX2. Moreover, β cells from diabetic humans with impaired insulin secretion also had reduced SIX2 transcript levels. Revealing how SIX2 and SIX3 govern functional maturation and maintain developmental fate in native human β cells should advance β-cell replacement and other therapeutic strategies for diabetes.
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Tellez K, Hang Y, Gu X, Chang CA, Stein RW, Kim SK. In vivo studies of glucagon secretion by human islets transplanted in mice. Nat Metab 2020; 2:547-557. [PMID: 32694729 PMCID: PMC7739959 DOI: 10.1038/s42255-020-0213-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 04/24/2020] [Indexed: 02/06/2023]
Abstract
Little is known about regulated glucagon secretion by human islet α-cells compared to insulin secretion from β-cells, despite conclusive evidence of dysfunction in both cell types in diabetes mellitus. Distinct insulins in humans and mice permit in vivo studies of human β-cell regulation after human islet transplantation in immunocompromised mice, whereas identical glucagon sequences prevent analogous in vivo measures of glucagon output from human α-cells. Here, we use CRISPR-Cas9 editing to remove glucagon codons 2-29 in immunocompromised NSG mice, preserving the production of other proglucagon-derived hormones. Glucagon knockout NSG (GKO-NSG) mice have metabolic, liver and pancreatic phenotypes associated with glucagon-signalling deficits that revert after transplantation of human islets from non-diabetic donors. Glucagon hypersecretion by transplanted islets from donors with type 2 diabetes revealed islet-intrinsic defects. We suggest that GKO-NSG mice provide an unprecedented resource to investigate human α-cell regulation in vivo.
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Camunas-Soler J, Dai XQ, Hang Y, Bautista A, Lyon J, Suzuki K, Kim SK, Quake SR, MacDonald PE. Patch-Seq Links Single-Cell Transcriptomes to Human Islet Dysfunction in Diabetes. Cell Metab 2020; 31:1017-1031.e4. [PMID: 32302527 PMCID: PMC7398125 DOI: 10.1016/j.cmet.2020.04.005] [Citation(s) in RCA: 168] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 01/23/2020] [Accepted: 04/02/2020] [Indexed: 12/16/2022]
Abstract
Impaired function of pancreatic islet cells is a major cause of metabolic dysregulation and disease in humans. Despite this, it remains challenging to directly link physiological dysfunction in islet cells to precise changes in gene expression. Here we show that single-cell RNA sequencing combined with electrophysiological measurements of exocytosis and channel activity (patch-seq) can be used to link endocrine physiology and transcriptomes at the single-cell level. We collected 1,369 patch-seq cells from the pancreata of 34 human donors with and without diabetes. An analysis of function and gene expression networks identified a gene set associated with functional heterogeneity in β cells that can be used to predict electrophysiology. We also report transcriptional programs underlying dysfunction in type 2 diabetes and extend this approach to cryopreserved cells from donors with type 1 diabetes, generating a valuable resource for understanding islet cell heterogeneity in health and disease.
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DuPont JJ, Kenney RM, Kim SK, Baur W, Lu Q, Martin G, Pulakat L. Sex differences in the role of the vascular angiotensin II receptors in vascular aging. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.04314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kim S, Whitener RL, Peiris H, Gu X, Chang CA, Lam JY, Camunas-Soler J, Park I, Bevacqua RJ, Tellez K, Quake SR, Lakey JRT, Bottino R, Ross PJ, Kim SK. Molecular and genetic regulation of pig pancreatic islet cell development. Development 2020; 147:dev186213. [PMID: 32108026 PMCID: PMC7132804 DOI: 10.1242/dev.186213] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 02/20/2020] [Indexed: 12/12/2022]
Abstract
Reliance on rodents for understanding pancreatic genetics, development and islet function could limit progress in developing interventions for human diseases such as diabetes mellitus. Similarities of pancreas morphology and function suggest that porcine and human pancreas developmental biology may have useful homologies. However, little is known about pig pancreas development. To fill this knowledge gap, we investigated fetal and neonatal pig pancreas at multiple, crucial developmental stages using modern experimental approaches. Purification of islet β-, α- and δ-cells followed by transcriptome analysis (RNA-seq) and immunohistology identified cell- and stage-specific regulation, and revealed that pig and human islet cells share characteristic features that are not observed in mice. Morphometric analysis also revealed endocrine cell allocation and architectural similarities between pig and human islets. Our analysis unveiled scores of signaling pathways linked to native islet β-cell functional maturation, including evidence of fetal α-cell GLP-1 production and signaling to β-cells. Thus, the findings and resources detailed here show how pig pancreatic islet studies complement other systems for understanding the developmental programs that generate functional islet cells, and that are relevant to human pancreatic diseases.
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Moon JH, Kim YG, Kim K, Osonoi S, Wang S, Saunders DC, Wang J, Yang K, Kim H, Lee J, Jeong JS, Banerjee RR, Kim SK, Wu Y, Mizukami H, Powers AC, German MS, Kim H. Serotonin Regulates Adult β-Cell Mass by Stimulating Perinatal β-Cell Proliferation. Diabetes 2020; 69:205-214. [PMID: 31806625 PMCID: PMC6971487 DOI: 10.2337/db19-0546] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Accepted: 11/14/2019] [Indexed: 12/21/2022]
Abstract
A sufficient β-cell mass is crucial for preventing diabetes, and perinatal β-cell proliferation is important in determining the adult β-cell mass. However, it is not yet known how perinatal β-cell proliferation is regulated. Here, we report that serotonin regulates β-cell proliferation through serotonin receptor 2B (HTR2B) in an autocrine/paracrine manner during the perinatal period. In β-cell-specific Tph1 knockout (Tph1 βKO) mice, perinatal β-cell proliferation was reduced along with the loss of serotonin production in β-cells. Adult Tph1 βKO mice exhibited glucose intolerance with decreased β-cell mass. Disruption of Htr2b in β-cells also resulted in decreased perinatal β-cell proliferation and glucose intolerance in adulthood. Growth hormone (GH) was found to induce serotonin production in β-cells through activation of STAT5 during the perinatal period. Thus, our results indicate that GH-GH receptor-STAT5-serotonin-HTR2B signaling plays a critical role in determining the β-cell mass by regulating perinatal β-cell proliferation, and defects in this pathway affect metabolic phenotypes in adults.
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Ramaswamy RS, Tiwari T, Darcy MD, Kim SK, Akinwande O, Dasgupta N, Guevara CJ. Cryoablation of low-flow vascular malformations. ACTA ACUST UNITED AC 2020; 25:225-230. [PMID: 31063139 DOI: 10.5152/dir.2019.18278] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
PURPOSE We aimed to evaluate the safety and effectiveness of cryoablation in the treatment of low-flow malformations, specifically venous malformation (VM) and fibroadipose vascular anomaly (FAVA). METHODS We conducted a retrospective review of 11 consecutive patients with low-flow malformations (14 lesions; 9 VM, 5 FAVA), median lesion volume 10.8 cm3, (range, 1.8-55.6 cm3) with a median age of 19 years (range, 10-50 years) who underwent cryoablation to achieve symptomatic control. Average follow-up was at a median of 207 days postprocedure (range, 120-886 days). Indications for treatment included focal pain and swelling. Technical success was achieved if the cryoablation ice ball covered the region of the malformation that corresponded to the patient's symptoms. Clinical success was considered complete if all symptoms resolved and partial if some symptoms persisted but did not necessitate further treatment. RESULTS The technical success rate was 100%. At 1-month follow-up, 13 of 14 lesions (93%) had a complete response and one (7%) had a partial response. At 6-month follow-up 12 of 13 (92%) had a complete response and 1 (8%) had a partial response. A total of 6 patients underwent primary cryoablation. Out of 9 VM cases, 7 had prior sclerotherapy and 2 had primary cryoablation. Out of the 5 FAVA cases, 1 had prior sclerotherapy and the remaining 4 cases underwent primary cryoablation. There were 3 minor complications following cryoablation including 2 cases of skin blisters and 1 case of transient numbness. These complications resolved with conservative management. CONCLUSION Cryoablation is safe and effective in the treatment of low-flow vascular malformations, either after sclerotherapy or as primary treatment.
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Eun L, Kim SK, Kim JK. P4641Are coronary artery abnormalities in Kawasaki disease associated with iron deficiency anemia? Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz745.1023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
Purpose
Coronary artery abnormalities (CAA) are the most important complication of Kawasaki disease (KD). Iron deficiency anemia (IDA) is prevalent micronutrient deficiencies and its association with KD remains unknown. We hypothesized the presence of IDA could be a predictor of CAA.
Methods
This retrospective study included 173 KD patients, divided into two groups by absence (Group 1) and presence (Group 2) of CAA. The odds ratio (OR) with 95% confidence interval (CI) was calculated using a logistic regression model to estimate the association between CAA and other indicators. Due to the collinearity between the IDA indicators, each indicator was paired with anemia in 3 models.
Results
The 3 indicators of IDA, serum iron, iron saturation and ferritin, were all significantly higher in Group 1 than in Group 2. Three sets of models including anemia with iron indicators produced the odd ratio (OR) of CAA of 3.513, 3.171, and 2.256, respectively. The 3 indicators of IDA were negatively associated with CAA, by OR of 0.965, 0.914, and 0.944, respectively. The Area under the curve (AUC) of ferritin, iron saturation, serum iron, anemia, and Kobayashi score was 0.907 (95% CI, 0.851–0.963), 0.729 (95% CI, 0.648–0.810), 0.711 (95% CI, 0.629–0.793), 0.638 (95% CI, 0.545–0.731), and 0.563 (95% CI, 0.489–0.636) respectively.
Figure 1 & 3
Conclusion
The indicators of IDA, especially ferritin, were highly associated with CAA, so that they were stronger predictors compared to the Kobayashi score. The IDA indicators can be used to predict CAA development and suggest the need for early intervention.
Acknowledgement/Funding
None
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Yang SM, Park JK, Na YS, Wang ZR, Ko WH, In Y, Lee JH, Lee KD, Kim SK. Nonambipolar Transport due to Electrons with 3D Resistive Response in the KSTAR Tokamak. PHYSICAL REVIEW LETTERS 2019; 123:095001. [PMID: 31524439 DOI: 10.1103/physrevlett.123.095001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 07/19/2019] [Indexed: 06/10/2023]
Abstract
A small nonaxisymmetric (3D) magnetic field can induce nonambipolar transport of the particle species confined in a tokamak and thus a significant change of plasma rotation. This process can be in a favor of instability control in the region where the tokamak plasma is sufficiently collisional and resistive, as observed in the applications of n=1 resonant magnetic perturbations to the KSTAR tokamak. The plasma rotation can be globally accelerated due to radially drifting electrons and constrained to the electron root, if the radial transport is enhanced by an amplified 3D response. This mechanism is verified by a kinetically self-consistent magnetohydrodynamic modeling for both response and transport, which offers the quantitative explanations on the internal n=1 structure detected by electron-cyclotron-emission imaging and the cocurrent plasma spinning observed in the experiments.
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Adhikari G, Adhikari P, de Souza EB, Carlin N, Choi S, Djamal M, Ezeribe AC, Ha C, Hahn IS, Jeon EJ, Jo JH, Joo HW, Kang WG, Kang W, Kauer M, Kim GS, Kim H, Kim HJ, Kim KW, Kim NY, Kim SK, Kim YD, Kim YH, Ko YJ, Kudryavtsev VA, Lee HS, Lee J, Lee JY, Lee MH, Leonard DS, Lynch WA, Maruyama RH, Mouton F, Olsen SL, Park BJ, Park HK, Park HS, Park KS, Pitta RLC, Prihtiadi H, Ra SJ, Rott C, Shin KA, Scarff A, Spooner NJC, Thompson WG, Yang L, Yu GH. Search for a Dark Matter-Induced Annual Modulation Signal in NaI(Tl) with the COSINE-100 Experiment. PHYSICAL REVIEW LETTERS 2019; 123:031302. [PMID: 31386435 DOI: 10.1103/physrevlett.123.031302] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Indexed: 06/10/2023]
Abstract
We present new constraints on the dark matter-induced annual modulation signal using 1.7 years of COSINE-100 data with a total exposure of 97.7 kg yr. The COSINE-100 experiment, consisting of 106 kg of NaI(Tl) target material, is designed to carry out a model-independent test of DAMA/LIBRA's claim of WIMP discovery by searching for the same annual modulation signal using the same NaI(Tl) target. The crystal data show a 2.7 cpd/kg/keV background rate on average in the 2-6 keV energy region of interest. Using a χ-squared minimization method we observe best fit values for modulation amplitude and phase of 0.0092±0.0067 cpd/kg/keV and 127.2±45.9 d, respectively.
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Kockel L, Griffin C, Ahmed Y, Fidelak L, Rajan A, Gould EP, Haigney M, Ralston B, Tercek RJ, Galligani L, Rao S, Huq L, Bhargava HK, Dooner AC, Lemmerman EG, Malusa RF, Nguyen TH, Chung JS, Gregory SM, Kuwana KM, Regenold JT, Wei A, Ashton J, Dickinson P, Martel K, Cai C, Chen C, Price S, Qiao J, Shepley D, Zhang J, Chalasani M, Nguyen K, Aalto A, Kim B, Tazawa-Goodchild E, Sherwood A, Rahman A, Wu SYC, Lotzkar J, Michaels S, Aristotle H, Clark A, Gasper G, Xiang E, Schlör FL, Lu M, Haering K, Friberg J, Kuwana A, Lee J, Liu A, Norton E, Hamad L, Lee C, Okeremi D, diTullio H, Dumoulin K, Chi SYG, Derossi GS, Horowitch RE, Issa EC, Le DT, Morales BC, Noori A, Shao J, Cho S, Hoang MN, Johnson IM, Lee KC, Lee M, Madamidola EA, Schmitt KE, Byan G, Park T, Chen J, Monovoukas A, Kang MJ, McGowan T, Walewski JJ, Simon B, Zu SJ, Miller GP, Fitzpatrick KB, Lantz N, Fox E, Collette J, Kurtz R, Duncan C, Palmer R, Rotondo C, Janicki E, Chisholm T, Rankin A, Park S, Kim SK. An Interscholastic Network To Generate LexA Enhancer Trap Lines in Drosophila. G3 (BETHESDA, MD.) 2019; 9:2097-2106. [PMID: 31040111 PMCID: PMC6643891 DOI: 10.1534/g3.119.400105] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 04/16/2019] [Indexed: 12/31/2022]
Abstract
Binary expression systems like the LexA-LexAop system provide a powerful experimental tool kit to study gene and tissue function in developmental biology, neurobiology, and physiology. However, the number of well-defined LexA enhancer trap insertions remains limited. In this study, we present the molecular characterization and initial tissue expression analysis of nearly 100 novel StanEx LexA enhancer traps, derived from the StanEx1 index line. This includes 76 insertions into novel, distinct gene loci not previously associated with enhancer traps or targeted LexA constructs. Additionally, our studies revealed evidence for selective transposase-dependent replacement of a previously-undetected KP element on chromosome III within the StanEx1 genetic background during hybrid dysgenesis, suggesting a molecular basis for the over-representation of LexA insertions at the NK7.1 locus in our screen. Production and characterization of novel fly lines were performed by students and teachers in experiment-based genetics classes within a geographically diverse network of public and independent high schools. Thus, unique partnerships between secondary schools and university-based programs have produced and characterized novel genetic and molecular resources in Drosophila for open-source distribution, and provide paradigms for development of science education through experience-based pedagogy.
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