Endocrinology
Abstract
Estrogen is a critical regulator of endometrial health. Aberrant estrogen stimulation can result in infertility, endometrial cancer, and endometriosis. Here, we identified Zinc Finger MIZ-Type Containing 1 (Zmiz1) as a coregulator of uterine estrogen signaling. ZMIZ1 is colocalized with an estrogen receptor α–binding (ESR1-binding) super enhancer. ZMIZ1 mutations are found in endometrial cancer and its RNA levels trend toward reduction in endometrium of patients with endometriosis. ZMIZ1 is dynamically expressed in human endometrial tissues during the menstrual cycle. Disrupting ZMIZ1 in cultured human endometrial stromal cells resulted in impaired cell proliferation and decidual differentiation. Ablation of Zmiz1 using the PgrCre mouse (Zmiz1d/d) resulted in infertility and accelerated age-dependent uterine fibrosis. Zmiz1d/d mice showed reduced ovulation and progesterone levels while maintaining normal serum prolactin during pregnancy. Uteri of Zmiz1d/d mice were unable to undergo a hormonally induced decidual response, had decreased expression of stromal progesterone receptor (PGR) and decreased stromal and epithelial cell proliferation. Analysis of the transcriptome of Zmiz1d/d mouse uteri showed decreased E2F, CCNA2, and FOXM1 signaling. Challenging ovariectomized Zmiz1d/d mice with estrogen resulted in a decreased amplitude of some estrogen-regulated gene responses. Our findings demonstrate the importance of ZMIZ1 as an ESR1 coregulator in uterine biology and pathology.
Authors
Sylvia C. Hewitt, Frank Orellana, Ryan M. Marquardt, MyeongJin Yi, Cynthia J. Willson, Mark Y. Chiang, Yong Song, Goutham Venkata Naga Davuluri, Christopher Day, Ramakrishna Kommagani, Joseph Rodriguez, Asgerally T. Fazleabas, John P. Lydon, Francesco J. DeMayo
Abstract
BACKGROUND. Checkpoint inhibitor-associated autoimmune diabetes (CIADM) is a rare but life-altering complication of immune checkpoint inhibitor (ICI) therapy. Biomarkers that predict type 1 diabetes (T1D) are unreliable for CIADM. AIM. To identify biomarkers for prediction of CIADM. METHODS. From our prospective biobank, 14 CIADM patients who had metastatic melanoma treated with anti-PD-1 ± anti-CTLA4 were identified. Controls were selected from the same biobank, matched 2:1. Pre-treatment, on-ICI and post-CIADM serum and peripheral blood mononuclear cells (PBMCs) were analysed. Serum was analysed for T1D autoantibodies, C-peptide, glucose and cytokines. PBMCs were profiled using flow cytometry. Pancreatic volume was measured using CT volumetry. RESUTLS. Before treatment, CIADM patients had smaller pancreatic volume (27% reduction, p=0.044) and higher anti-GAD antibody titres (median 2.9 versus 0, p=0.01). They had significantly higher baseline proportions of Th17 helper cells (p=0.03), higher CD4+ central memory cells (p=0.04) and lower naïve CD4+ cells (p=0.01). With ICI treatment, greater declines in pancreatic volume were seen in CIADM patients (p<0.0001). Activated CD4+ subsets increased significantly in CIADM and controls with immune-related adverse effects (IRAE) but not controls without IRAE. Using only pre-treatment results, pancreatic volume, anti-GAD antibody titre and baseline immune flow profile were highly predictive of CIADM development, with an area under the curve (AUC) of >0.96. CONCLUSIONS. People who develop CIADM are immunologically predisposed and have antecedent pancreatic and immunological changes that accurately predict disease with excellent sensitivity. These biomarkers could be used to guide ICI use, particularly when planning treatment for low-risk tumours. FUNDING. JEG is supported by NHMRC Investigator grant 2033228. AMM by NHMRC Investigator grant 2009476 and GVL by NHMRC Investigator grant 2007839.
Authors
Linda Wu, John M. Wentworth, Christopher Liddle, Nicole Fewings, Matteo Carlino, David A. Brown, Roderick Clifton-Bligh, Georgina V. Long, Richard A. Scolyer, Nicholas Norris, Sarah C. Sasson, Venessa H.M. Tsang, Alexander M. Menzies, Jenny E. Gunton
Abstract
In pancreatic β-cells, misfolded proinsulin is a substrate for Endoplasmic Reticulum-Associated protein Degradation (ERAD) via HRD1/SEL1L. β-cell HRD1 activity is alternately reported to improve, or impair, insulin biogenesis. Further, while β-cell SEL1L deficiency causes HRD1 hypofunction and diminishes islet insulin content; reports conflict as to whether β-cell ERAD deficiency increases or decreases proinsulin levels. Here we’ve examined β-cell-specific Hrd1-KO mice (chronic deficiency), plus rodent (and human islet) β-cells treated acutely with HRD1 inhibitor. β-Hrd1-KO mice developed diabetes with decreased islet proinsulin yet a relative increase of misfolded proinsulin re-distributed to the ER; upregulated biochemical markers of β-cell ER stress and autophagy; electron microscopic evidence of ER enlargement and decreased insulin granule content; and increased glucagon-positive islet cells. Misfolded proinsulin was also increased in islets treated with inhibitors of lysosomal degradation. Preceding any loss of total proinsulin, acute HRD1 inhibition triggered increased nonnative proinsulin, increased phospho-eIF2ɑ with inhibited proinsulin synthesis, and increased LC3b-II (the abundance of which requires expression of SigmaR1). We posit a subset of proinsulin molecules undergoes HRD1-mediated disposal. When HRD1 is unavailable, misfolded proinsulin accumulates, accompanied by increased phospho-eIF2ɑ that limits further proinsulin synthesis, plus SigmaR1-dependent autophagy activation, ultimately lowering steady-state β-cell proinsulin (and insulin) levels — triggering diabetes.
Authors
Anoop Arunagiri, Leena Haataja, Maroof Alam, Noah F. Gleason, Emma Mastroianni, Chao-Yin Cheng, Sami Bazzi Onton, Jeffrey Knupp, Ibrahim Metawea, Anis Hassan, Dennis Larkin, Deyu Fang, Billy Tsai, Ling Qi, Peter Arvan
Abstract
Hereditary pheochromocytoma and paraganglioma (hPPGL) is caused by pathogenic mutations in succinate dehydrogenase (SDH) genes, commonly SDHB. However, over 80% of SDHB missense variants are classified as variants of uncertain significance (VUS), limiting clinical interpretation and diagnostic utility of germline testing. To provide functional evidence of SDHB allele pathogenicity or benignity, we developed a cellular complementation assay that quantifies intracellular succinate/fumarate ratios as a readout of SDH enzymatic activity. This assay reliably distinguished pathogenic from benign alleles with high fidelity, outperforming and complementing computational predictions. Functional assessment of patient-derived VUS alleles supported reclassification of 87% of tested variants and revealed that mutations in the iron–sulfur cluster domain were amorphic, while those at or beyond the C-terminal residue Tyr273 retained function. Variants associated with Leigh syndrome retained activity, consistent with their biallelic inheritance and distinct pathogenic mechanisms from SDHB-related tumorigenesis. Notably, hypomorphic pathogenic SDHB variants correlated with increased head and neck paraganglioma occurrence, revealing a genotype–phenotype relationship. Functional characterization of SDHB missense variants supports clinical classification, informs hPPGL risk stratification, and has immediate diagnostic impact.
Authors
Sooyeon Lee, Leor Needleman, Julie Park, Rebecca C. Schugar, Qianjin Guo, James M. Ford, Justin P. Annes
Abstract
Mixed hematopoietic chimerism after allogeneic hematopoietic cell transplantation (HCT) promotes tolerance of transplanted donor-matched solid organs, corrects autoimmunity, and could transform therapeutic strategies for autoimmune type 1 diabetes (T1D). However, development of non-toxic bone marrow conditioning protocols is needed to expand clinical use. We developed a chemotherapy-free, non-myeloablative (NMA) conditioning regimen that achieves mixed chimerism and allograft tolerance across MHC barriers in NOD mice. We obtained durable mixed hematopoietic chimerism in prediabetic NOD mice using anti-c-Kit monoclonal antibody, T-cell depleting antibodies, JAK1/2 inhibition, and low-dose total body irradiation prior to transplantation of MHC-mismatched B6 hematopoietic cells, preventing diabetes in 100% of chimeric NOD:B6 mice. In overtly diabetic NOD mice, NMA conditioning followed by combined B6 HCT and islet transplantation durably corrected diabetes in 100% of chimeric mice without chronic immunosuppression or graft-versus-host disease (GVHD). Chimeric mice remained immunocompetent, as assessed by blood count recovery and rejection of 3rd party allogeneic islets. Adoptive transfer studies and analysis of autoreactive T cells confirmed correction of autoimmunity. Analysis of chimeric NOD mice revealed central thymic deletion and peripheral tolerance mechanisms. Thus, with NMA conditioning and cell transplantation, we achieved durable hematopoietic chimerism without GVHD, promoted islet allograft tolerance, and reversed established T1D.
Authors
Preksha Bhagchandani, Stephan A. Ramos, Bianca Rodriguez, Xueying Gu, Shiva Pathak, Yuqi Zhou, Yujin Moon, Nadia Nourin, Charles A. Chang, Jessica Poyser, Brenda J. Velasco, Weichen Zhao, Hye-Sook Kwon, Richard Rodriguez, Diego M. Burgos, Mario A. Miranda, Everett Meyer, Judith A. Shizuru, Seung K. Kim
Abstract
Intestinal function and white adipose tissue (WAT) function deteriorate with age, but whether and how their deterioration is intertwined remains unknown. Increased gut permeability, microbiota dysbiosis, and aberrant immune microenvironment are the hallmarks of intestinal dysfunctions in aging. Here, we show that subcutaneous WAT dysfunction triggered aging-like intestinal dysfunctions in mouse models. Removal of inguinal subcutaneous WAT (iWAT) increased intestinal permeability and inflammation and altered gut microbiota composition as well as susceptibility to pathogen infection in mouse models. These intestinal dysfunctions were accompanied by a reduction of immunoglobulin A–producing (IgA-producing) cells and IgA biosynthesis in the lamina propria of the small intestine. Retinoic acid (RA) is a key cargo within iWAT-derived extracellular vesicles (iWAT-EVs), which, at least in part, elicits IgA class-switching and production in the small intestine and maintains microbiota homeostasis. RA content in iWAT-EVs and intestinal IgA biosynthesis are reduced during aging in mice. Replenishment of “young” iWAT-EVs rejuvenates intestinal IgA production machinery and shifts microbiota composition of aged mice to a “youth” status, which alleviates leaky gut via RA. In conclusion, our findings suggest that iWAT-EVs with RA orchestrate IgA-mediated gut microbiota homeostasis by acting on intestinal B cells, thereby maintaining intestinal health during aging.
Authors
KeKao Long, Pujie Liu, Yi Wang, Jordy Evan Sulaiman, Moinul Hoque, Gloria Hoi Yee Li, Daisy Danyue Zhao, Pui-Kei Lee, Gilman Kit-hang Siu, Annie Wing-tung Lee, Zhuohao Liu, Pui-kin So, Yin Cai, Connie Wai-hong Woo, Chi-bun Chan, Aimin Xu, Kenneth King-yip Cheng
Abstract
Authors
Vinaya Simha, Mary Kate LoPiccolo, Anna Platt, Rebecca J. Brown, Xandria Johnson, Deanna Alexis Carere, Colleen Donnelly, Matthew T. Snyder, Chao Xing, Thomas P. Mathews, Purva Gopal, Stephen C. Ward, Diana R. Tomchick, Anil K. Agarwal, Ralph J. DeBerardinis, Abhimanyu Garg
Abstract
It is now recognized that patients and animal models expressing genetically-encoded misfolded mutant thyroglobulin (TG, the protein precursor for thyroid hormone synthesis) exhibit dramatic swelling of the endoplasmic reticulum (ER) with ER stress and cell death in thyrocytes — seen both in homozygotes (with severe hypothyroidism) and heterozygotes (with subclinical hypothyroidism). The thyrocyte death phenotype is exacerbated upon thyroidal stimulation (by thyrotropin, TSH), as cell death is inhibited upon treatment with exogenous thyroxine. TSH stimulation might contribute to cytotoxicity by promoting ER stress, or by an independent mechanism. Here we’ve engineered knockout mice completely lacking Tg expression. Like other animals/patients with mutant TG, these animals rapidly develop severe goitrous hypothyroidism; however, thyroidal ER stress is exceedingly low — lower even than that seen in wildtype mice. Nevertheless, mice lacking TG exhibit abundant thyroid cell death, which depends upon renegade thyroidal iodination — it is completely suppressed in a genetic model lacking effective iodination, or in Tg-KO mice treated with propylthiouracil (iodination inhibitor), or iodide deficiency. Thyrocytes in culture are killed not in the presence of H2O2 alone, but rather upon peroxidase-mediated iodination, with cell death blocked by propylthiouracil. Thus, in the thyroid gland bearing Tg mutation(s), TSH-stimulated iodination activity triggers thyroid cell death.
Authors
Crystal Young, Xiaohan Zhang, Xiaofan Wang, Aaron P. Kellogg, Kevin Pena, August Z. Cumming, Xiao-Hui Liao, Dennis Larkin, Hao Zhang, Emma Mastroianni, Helmut Grasberger, Samuel Refetoff, Peter Arvan
Abstract
Impaired glucose-stimulated insulin secretion (GSIS) is a hallmark of β-cell dysfunction in diabetes. Epigenetic mechanisms govern cellular glucose sensing and GSIS by β-cells, but they remain incompletely defined. Here, we found that BAF60a functions as a chromatin regulator that sustains biphasic GSIS and preserves β-cell function under metabolic stress conditions. BAF60a was downregulated in β-cells from obese and diabetic mice, monkeys, and humans. β-cell-specific inactivation of BAF60a in adult mice impaired GSIS, leading to hyperglycemia and glucose intolerance. Conversely, restoring BAF60a expression improved β-cell function and systemic glucose homeostasis. Mechanistically, BAF60a physically interacted with Nkx6.1 to selectively modulate chromatin accessibility and transcriptional activity of target genes critical for GSIS coupling in islet β-cells. A BAF60a V278M mutation associated with decreased β-cell GSIS function was identified in human subjects. Mice carrying this mutation, which disrupted the interaction between BAF60a and Nkx6.1, displayed β-cell dysfunction and impaired glucose homeostasis. In addition, GLP-1R and GIPR expression was significantly reduced in BAF60a-deficient islets, attenuating the insulinotropic effect of GLP-1R agonists. Together, these findings support a role for BAF60a as a component of the epigenetic machinery that shapes the chromatin landscape in β-cells critical for glucose sensing and insulin secretion.
Authors
Xinyuan Qiu, Ruo-Ran Wang, Qing-Qian Wu, Hongxing Fu, Shuaishuai Zhu, Wei Chen, Wen Wang, Haide Chen, Xiuyu Ji, Wenjing Zhang, Dandan Yan, Jing Yan, Li Jin, Rong Zhang, Mengjie Shi, Ping Luo, Yingqing Yang, Qintao Wang, Ziyin Zhang, Wei Ding, Xiaowen Pan, Chengbin Li, Bin Liang, Guoji Guo, Hai-long Piao, Min Zheng, Yan Sheng, Lingyun Zhu, Cheng Hu, Zhuo-Xian Meng
Abstract
Teplizumab, a humanized anti-CD3 monoclonal antibody, represents a breakthrough in autoimmune type 1 diabetes (T1D) treatment, by delaying clinical onset in stage 2 and slowing progression in early stage 3. However, therapeutic responses are heterogeneous. To better understand this variability, we applied single-cell transcriptomics to paired peripheral blood and pancreas samples from anti-mouse CD3-treated non-obese diabetic (NOD) mice and identified distinct gene signatures associated with therapy outcome, with consistent patterns across compartments. Success-associated signatures were enriched in NK/CD8⁺ T cells and other immune cell types, whereas resistance signatures were predominantly expressed by neutrophils. The immune communities underlying these response signatures were confirmed in human whole-blood sequencing data from the AbATE study at 6 months, which assessed teplizumab therapy in stage 3 T1D. Furthermore, baseline expression profiling in the human TN10 (stage 2) and AbATE (stage 3) cohorts identified immune signatures predictive of therapy response, T cell-enriched signatures in responders and neutrophil-enriched signatures in non-responders, highlighting the roles of both adaptive and innate immunity in determining teplizumab outcome. Using an elastic-net logistic regression model, we developed a 26-gene blood-based signature predicting teplizumab response (AUC = 0.97). These findings demonstrate the predictive potential of immune gene signatures and the value of transcriptomic profiling in guiding individualized treatment strategies with teplizumab in T1D.
Authors
Gabriele Sassi, Pierre Lemaitre, Laia Fernández Calvo, Francesca Lodi, Álvaro Cortés Calabuig, Samal Bissenova, Amber Wouters, Laure Degroote, Marijke Viaene, Niels Vandamme, Lauren Higdon, Peter S. Linsley, S. Alice Long, Chantal Mathieu, Conny Gysemans
Copyright © 2025 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)