Pancreatic β-cell identity loss is increasingly recognized as a critical pathogenic contributor to β-cell failure in type 2 diabetes (T2D), but the specific mechanism remains to be characterized. In this study, we demonstrate that zinc accumulation contributes to β-cell identity loss during diabetes progression in both human and mouse islets. Using a model of human embryonic stem cell-derived islets (SC-islets), we reveal that accumulated zinc triggers the integrated stress response (ISR), with elevated ATF4 expression in SC-β cells. This, in turn, initiates expression of the α cell-specific transcription factor ARX, resulting in the conversion of β cells to α cells, thus forming a zinc-ATF4-ARX regulatory axis. Like primary β cells, SC-β cells also undergo identity loss after transplantation into diabetic animals, which can be prevented by an ISR inhibitor, resulting in improved glycemic control. Furthermore, both genetic depletion and chemical inhibition of zinc accumulation effectively safeguard SC-β cells from identity loss and enhance their efficacy in diabetic animals. Our study thus reveals a pathogenic mechanism in which zinc accumulation induces β-cell identity loss through lineage-tracing approaches and proposes a protective strategy to counteract this process.

The clinical application of human stem cell-derived islet organoids (SC-islets) is hindered by immaturity and ischemia-induced dysfunction post-transplantation. Hypoxia-driven angiogenesis is a common adaptation, but the metabolic fragility of SC-islet β cells leads to early functional damage and suppressed vascular endothelial growth factor A (VEGFA) expression, thereby delaying vascularization and causing graft loss. The key challenge in SC-islet transplantation is how to prevent hypoxia-induced stress and promote rapid angiogenesis. We found that excessive zinc in SC-islet β cells induces oxidative modification that inhibits AMP-activated protein kinase (AMPK) activity. Chemical inhibition of zinc transportation activates AMPK, enhances functional maturation, improves hypoxia resistance, and increases hypoxia-inducible factor 1α (HIF1A)-independent VEGFA expression to facilitate endothelial cell integration. In diabetic animal models, this approach significantly improved hypoxia resistance, accelerated angiogenesis, and enhanced glycemic control. Our findings demonstrate that chemical inhibition of zinc transportation boosts SC-islet functional competence, offering a potential strategy to advance pre-adaptation to stress in regenerative medicine.

Diabetes is often associated with delayed wound healing, where endothelial progenitor cells (EPCs) play a key role in maintaining vascular integrity and promoting angiogenesis. Urolithin A, a metabolite derived from pomegranates, strawberries, and nuts, has demonstrated therapeutic potential in reversing damage in various disease models, indicating its potential in facilitating diabetic wound healing. In this study, we investigated the effects of Urolithin A on mitochondrial dysfunction, apoptosis, and impaired function in EPCs treated with high glucose. Through sequencing and molecular docking analysis, we found that Urolithin A exerts its therapeutic action by upregulating Parkin and activating mitophagy. Furthermore, Urolithin A alleviated delayed wound healing in diabetic rat models. In conclusion, Urolithin A holds promise as a therapeutic agent for improving diabetes-related delayed wound healing by targeting mitochondrial dysfunction and enhancing EPC function.

Zinc is an essential trace element that participates in a wide range of physiological processes. Cellular zinc homeostasis is tightly controlled by two families of transporters: the Zrt/Irt-like protein (ZIP/SLC39) family, which mediates zinc influx into the cytoplasm, and the zinc transporter (ZnT/SLC30) family, which facilitates zinc efflux or sequestration into intracellular organelles. Growing evidence implicates dysregulated expression or function of zinc transporters in the onset and progression of diverse pathological conditions. In this review, we provide a comprehensive overview of the molecular regulation and recent advances on ZIPs and ZnTs in diabetes and related disorders, including obesity, neurodegenerative diseases, cancers and immune dysregulation. We also discuss ongoing scientific controversies regarding the mechanistic roles of zinc transporters, particularly ZnT8, in the pathogenesis of diabetes. Finally, we provide perspectives on the translational potential of zinc transporter-targeted strategies in precision medicine.

CD47-blocking antibody is a well-known potential antibody drug for tumor immunotherapy. However, it is unclear whether CD47-blocking antibody can protect against metabolic disorders. We report that high-fat diet (HFD)-induced obesity increases CD47 expression, while exercise downregulates it in skeletal muscle. Administration of CD47-blocking antibody in mice prevents HFD-induced weight gain and glucose intolerance, enhances exercise capacity, and improves body composition and skeletal muscle mitochondrial function. Mechanistically, the protective effects conferred by CD47-blocking antibody are mediated through activation of AMP-activated protein kinase (AMPK) in skeletal muscle. Consistently, muscle-specific CD47-knockout mice show similar metabolic improvements, indicating a direct muscle-specific role of CD47 in regulating AMPK activation in vivo. Furthermore, the CD47-blocking antibody reduces the phosphorylation of heat shock protein 90α (HSP90α) to activate AMPK in skeletal muscle. In conclusion, CD47-blocking antibody confers metabolic benefits by activating the AMPK pathway in skeletal muscle.

Pancreatic β cell loss by cellular stress contributes to diabetes pathogenesis. Nevertheless, the fundamental mechanism of cellular stress regulation remains elusive. Here, it is found that elevated zinc transportation causes excessive cellular stress in pancreatic β cells in diabetes. With gene-edited human embryonic stem cell-derived β cells (SC-β cells) and human primary islets, the results reveal that elevated zinc transportation initiates the integrated stress response (ISR), and ultimately leads to β cell death. By contrary, genetic abolishment of zinc transportation shields β cells from exacerbated endoplasmic reticulum stress (ER stress) and concurrent ISR. To target excessive zinc transportation with a chemical inhibitor, an isogenic SC-β cells based drug-screening platform is established. Surprisingly, independent of its traditional role as protein synthesis inhibitor at a high-dose (10 µm), low-dose (25 nm) anisomycin significantly inhibits zinc transportation and effectively prevents β cell loss. Remarkably, in vivo administration of anisomycin in mice demonstrates protective effects on β cells and prevents type 2 diabetes induced by high-fat diet. Overall, elevated zinc transportation is identified as a crucial driver of β cell loss and low-dose anisomycin as a potential therapeutic molecule for diabetes.

Pancreatic β-cell failure by WFS1 deficiency is manifested in individuals with wolfram syndrome (WS). The lack of a suitable human model in WS has impeded progress in the development of new treatments. Here, human pluripotent stem cell derived pancreatic islets (SC-islets) harboring WFS1 deficiency and mouse model of β cell specific Wfs1 knockout were applied to model β-cell failure in WS. We charted a high-resolution roadmap with single-cell RNA-seq (scRNA-seq) to investigate pathogenesis for WS β-cell failure, revealing two distinct cellular fates along pseudotime trajectory: maturation and stress branches. WFS1 deficiency disrupted β-cell fate trajectory toward maturation and directed it towards stress trajectory, ultimately leading to β-cell failure. Notably, further investigation of the stress trajectory identified activated integrated stress response (ISR) as a crucial mechanism underlying WS β-cell failure, characterized by aberrant eIF2 signaling in WFS1 -deficient SC-islets, along with elevated expression of genes in regulating stress granule formation. Significantly, we demonstrated that ISRIB, an ISR inhibitor, efficiently reversed β-cell failure in WFS1 -deficient SC-islets. We further validated therapeutic efficacy in vivo with β-cell specific Wfs1 knockout mice. Altogether, our study provides novel insights into WS pathogenesis and offers a strategy targeting ISR to treat WS diabetes.

Obesity, a growing global health concern, is closely linked to depression. However, the neural mechanism of association between obesity and depression remains poorly understood. In this study, neural-specific WFS1 deficiency exacerbates the vicious cycle of obesity and depression in mice fed a high-fat diet (HFD), positioning WFS1 as a crucial factor in this cycle. Through human pluripotent stem cells (hESCs) neural differentiation, it is demonstrated that WFS1 regulates Zn2+ homeostasis and the apoptosis of neural progenitor cells (NPCs) and cerebral organoids by inhibiting the zinc transporter ZnT3 under the situation of dysregulated lipid metabolism. Notably, riluzole regulates ZnT3 expression to maintain zinc homeostasis and protect NPCs from lipotoxicity-induced cell death. Importantly, riluzole, a therapeutic molecule targeting the nervous system, in vivo administration prevents HFD-induced obesity and associated depression. Thus, a WFS1-ZnT3-Zn2+ axis critical is demonstrated for the vicious cycle of obesity and depression and that riluzole may have the potential to reverse this process against obesity and depression

The possible role of fatty acid translocase (CD36) in the treatment of obesity has gained increasing research interest since researchers recognized its coordinated function in fatty acid uptake and oxidation. However, the effect of CD36 deficiency on intracellular insulin signaling is complex and its impact may depend on different nutritional stresses. Therefore, we investigated the various effects of CD36 deletion on insulin signaling in C2C12 myotubes with or without palmitic acid (PA) overload. In the present work, we reported the upregulated expression levels of CD36 in the skeletal muscle tissues of obese humans and mice as well as in C2C12 myotubes with PA stimulation. CD36 knockdown using RNA interference showed that insulin signaling was impaired in CD36-deficient C2C12 cells in the absence of PA loading, suggesting that CD36 is essential for the maintenance of insulin action, possibly resulting from increased mitochondrial dysfunction and endoplasmic reticulum (ER) stress; however, CD36 deletion improved insulin signaling in the presence of PA overload due to a reduction in lipid overaccumulation. In conclusion, we identified differential roles of CD36 in regulating muscle insulin response under conditions with and without PA overload, which provides supportive evidence for further research into therapeutic approaches to diabetes.

Wfs1 is an endoplasmic reticulum (ER) membrane located protein highly expressed in pancreatic β cells and brain. Wfs1 deficiency causes adult pancreatic β cells dysfunction following β cells apoptosis. Previous studies mainly focus on the Wfs1 function in adult mouse pancreatic β cells. However, whether Wfs1 loss-of-function impairs mouse pancreatic β cell from its early development is unknown. In our study, Wfs1 deficiency disrupts the composition of mouse pancreatic endocrine cells from early postnatal day 0 (P0) to 8 weeks old, with decreased percentage of β cells and increased percentage of α and δ cells. Meanwhile, Wfs1 loss-of-function leads to reduced intracellular insulin content. Notably, Wfs1 deficiency impairs Glut2 localization and causes the accumulation of Glut2 in mouse pancreatic β cell cytoplasm. In Wfs1-deficient mice, glucose homeostasis is disturbed from early 3 weeks old to 8 weeks old. This work reveals that Wfs1 is significantly required for the composition of pancreatic endocrine cells and is essential for Glut2 localization in mouse pancreatic β cells.

Adult mammals have limited capacity to regenerate functional cells. Promisingly, in vivo transdifferentiation heralds the possibility of regeneration by lineage reprogramming from other fully differentiated cells. However, the process of regeneration by in vivo transdifferentiation in mammals is poorly understood. Using pancreatic β cell regeneration as a paradigm, we performed a single-cell transcriptomic study of in vivo transdifferentiation from adult mouse acinar cells to induced β cells. Using unsupervised clustering analysis and lineage trajectory construction, we uncovered that the cell fate remodeling trajectory was linear at the initial stage and the reprogrammed cells either evolved to induced β cells or toward a "dead-end" state after day 4.Moreover, functional analyses identified both p53 and Dnmt3a that acted as reprogramming barriers during the process of in vivo transdifferentiation. Collectively, we decipher a high-resolution roadmap of regeneration by in vivo transdifferentiation and provide a detailed molecular blueprint to facilitate mammalian regeneration.

Dysregulated neurite outgrowth and synapse formation underlie many psychiatric disorders, which are also manifested by wolfram syndrome (WS). Whether and how the causative gene WFS1 deficiency affects synapse formation remain elusive. By mirroring human brain development with cerebral organoids, WFS1-deficient cerebral organoids not only recapitulate the neuronal loss in WS patients, but also exhibit significantly impaired synapse formation and function associated with reduced astrocytes. WFS1 deficiency in neurons autonomously delays neuronal differentiation with altered expressions of genes associated with psychiatric disorders, and impairs neurite outgrowth and synapse formation with elevated cytosolic calcium. Intriguingly, WFS1 deficiency in astrocytes decreases the expression of glutamate transporter EAAT2 by NF-κB activation and induces excessive glutamate. When co-cultured with wildtype neurons, WFS1-deficient astrocytes lead to impaired neurite outgrowth and increased cytosolic calcium in neurons. Importantly, disrupted synapse formation and function in WFS1-deficient cerebral organoids and impaired neurite outgrowth affected by WFS1-deficient astrocytes are efficiently reversed with Riluzole treatment, by restoring EAAT2 expression in astrocytes. Furthermore, Riluzole rescues the depressive-like behavior in the forced swimming test and the impaired recognition and spatial memory in the novel object test and water maze test in Wfs1 conditional knockout mice. Altogether, our study provides novel insights into how WFS1 deficiency affects synapse formation and function, and offers a strategy to treat this disease.

Human embryonic stem cell-derived β cells (SC-β cells) hold great promise for treatment of diabetes, yet how to achieve functional maturation and protect them against metabolic stresses such as glucotoxicity and lipotoxicity remains elusive. Our single-cell RNA-seq analysis reveals that ZnT8 loss of function (LOF) accelerates the functional maturation of SC-β cells. As a result, ZnT8 LOF improves glucose-stimulated insulin secretion (GSIS) by releasing the negative feedback of zinc inhibition on insulin secretion. Furthermore, we demonstrate that ZnT8 LOF mutations endow SC-β cells with resistance to lipotoxicity/glucotoxicity-triggered cell death by alleviating endoplasmic reticulum (ER) stress through modulation of zinc levels. Importantly, transplantation of SC-β cells with ZnT8 LOF into mice with preexisting diabetes significantly improves glycemia restoration and glucose tolerance. These findings highlight the beneficial effect of ZnT8 LOF on the functional maturation and survival of SC-β cells that are useful as a potential source for cell replacement therapies.

Obesity-related muscular dysfunction and relative muscle atrophy affect an increasing number of people. Elucidating the molecular mechanisms of skeletal muscle cell development and growth may contribute to the maintenance of skeletal muscle mass in obesity. Fatty acid translocase (FAT/CD36), as a long-chain fatty acid transport protein, is crucial for lipid metabolism and signaling. CD36 is known to function in myogenic differentiation, and whether it affects the proliferation of skeletal muscle cells and the underlying mechanisms remain unclear. In this study, the effect of CD36 deficiency on skeletal muscle cell viability and proliferation was examined using C2C12 myoblasts. Results showed that the deletion of CD36 enhanced the inhibitory effect of PA on the proliferation and the promotion of apoptosis in skeletal muscle cells. Intriguingly, the silencing of CD36 suppressed cell proliferation by preventing the cell cycle from the G0/G1 phase to the S phase in a cyclin D1/CDK4-dependent manner. Overall, we demonstrated that CD36 was involved in skeletal muscle cell proliferation by cell cycle control, and these findings might facilitate the treatment of obesity-related muscle wasting.

Type 2 diabetes (T2D) is characterized by the malfunction of pancreatic β cells. Susceptibility and pathogenesis of T2D can be affected by multiple factors, including sex differences. However, the mechanisms underlying sex differences in T2D susceptibility and pathogenesis remain unclear. Using single-cell RNA sequencing (scRNA-seq), we demonstrate the presence of sexually dimorphic transcriptomes in mouse β cells. Using a high-fat diet-induced T2D mouse model, we identified sex-dependent T2D altered genes, suggesting sex-based differences in the pathological mechanisms of T2D. Furthermore, based on islet transplantation experiments, we found that compared to mice with sex-matched islet transplants, sex-mismatched islet transplants in healthy mice showed down-regulation of genes involved in the longevity regulating pathway of β cells. Moreover, the diabetic mice with sex-mismatched islet transplants showed impaired glucose tolerance. These data suggest sexual dimorphism in T2D pathogenicity, indicating that sex should be considered when treating T2D. We hope that our findings could provide new insights for the development of precision medicine in T2D.

Abstract Background Liver fibrosis and fibrosis‐related hepatocarcinogenesis are a rising cause for morbidity and death worldwide. Although transforming growth factor‐β (TGF‐β) is a critical mediator of chronic liver fibrosis, targeting TGF‐β isoforms and receptors lead to unacceptable side effect. This study was designed to explore the antifibrotic effect of Compound kushen injection (CKI), an approved traditional Chinese medicine formula, via a therapeutic strategy of rebalancing TGF‐β/Smad7 signaling. Methods A meta‐analysis was performed to evaluate CKI intervention on viral hepatitis‐induced fibrosis or cirrhosis in clinical randomized controlled trials (RCTs). Mice were given carbon tetrachloride (CCl4) injection or methionine‐choline deficient (MCD) diet to induce liver fibrosis, followed by CKI treatment. We examined the expression of TGF‐β/Smad signaling and typical fibrosis‐related genes in hepatic stellate cells (HSCs) and fibrotic liver tissues by qRT‐PCR, Western blotting, RNA‐seq, immunofluorescence, and immunohistochemistry. Results Based on meta‐analysis results, CKI improved the liver function and relieved liver fibrosis among patients. In our preclinical studies by using two mouse models, CKI treatment demonstrated promising antifibrotic effects and postponed hepatocarcinogenesis with improved liver function and histopathologic features. Mechanistically, we found that CKI inhibited HSCs activation by stabilizing the interaction of Smad7/TGF‐βR1 to rebalance Smad2/Smad3 signaling, and subsequently decreased the extracellular matrix formation. Importantly, Smad7 depletion abolished the antifibrotic effect of CKI in vivo and in vitro. Moreover, matrine, oxymatrine, sophocarpine, and oxysophocarpine were identified as material basis responsible for the antifibrosis effect of CKI. Conclusions Our results unveil the approach of CKI in rebalancing TGF‐β/Smad7 signaling in HSCs to protect against hepatic fibrosis and hepatocarcinogenesis in both preclinical and clinical studies. Our study suggests that CKI can be a candidate for treatment of hepatic fibrosis and related oncogenesis.

Glioblastoma (GBM) is an incurable and highly heterogeneous brain tumor, originating from human neural stem/progenitor cells (hNSCs/hNPCs) years ahead of diagnosis. Despite extensive efforts to characterize hNSCs and end-stage GBM at bulk and single-cell levels, the de novo gliomagenic path from hNSCs is largely unknown due to technical difficulties in early-stage sampling and preclinical modeling. Here, we established two highly penetrant hNSC-derived malignant glioma models, which resemble the histopathology and transcriptional heterogeneity of human GBM. Integrating time-series analyses of whole-exome sequencing, bulk and single-cell RNA-seq, we reconstructed gliomagenic trajectories, and identified a persistent NSC-like population at all stages of tumorigenesis. Through trajectory analyses and lineage tracing, we showed that tumor progression is primarily driven by multi-step transcriptional reprogramming and fate-switches in the NSC-like cells, which sequentially generate malignant heterogeneity and induce tumor phenotype transitions. We further uncovered stage-specific oncogenic cascades, and among the candidate genes we functionally validated C1QL1 as a new glioma-promoting factor. Importantly, the neurogenic-to-gliogenic switch in NSC-like cells marks an early stage characterized by a burst of oncogenic alterations, during which transient AP-1 inhibition is sufficient to inhibit gliomagenesis. Together, our results reveal previously undercharacterized molecular dynamics and fate choices driving de novo gliomagenesis from hNSCs, and provide a blueprint for potential early-stage treatment/diagnosis for GBM.

Single Pancreatic β Cell Transcriptomics Sexual Dimorphism of Transcriptomes and Identify Sex-dependent Type 2 Diabetes Abstract 56 Type 2 diabetes, characterized by malfunction of pancreatic β cells, is affected by 57 multiple cues including sex differences. Nevertheless, mechanisms of sex differences 58 in type 2 diabetes susceptibility and pathogenesis remain unclear. Using single-cell 59 RNA sequencing (scRNA-seq) technology, we showed that sexual dimorphism of 60 transcriptome exists in mouse β cells. Our analysis further revealed the existence of 61 sex-dependent type 2 diabetes altered genes in high fat diet induced T2D model, 62 suggesting divergences in pathological mechanisms of type 2 diabetes between sexes. 63 Our results indicated that sex should be taken into consideration when treating diabetes, 64 which was further validated by the sex-matched and sex-mismatched islet 65 transplantation in mice. Compared to sex-matched transplants, sex-mismatched 66 transplants showed downregulation of genes involved in the longevity regulating 67 pathway in β cells and led to impaired glucose tolerance in diabetic mice. Taken 68 together, our findings could advance current understanding of type 2 diabetes 69 pathogenesis with sexually dimorphic perspectives and provide new insights to the 70 development of precision medicine. 71

Human embryonic stem cells (hESCs) derived β cells (SC-β cells) hold great promise for diabetes treatment, yet how to achieve functional maturation of these SC-β cells and protect them against metabolic stresses such as glucotoxicity and lipotoxicity remain elusive. By single cell RNA-seq pseudotime analysis, we revealed that ZnT8 is involved in SC-β cells functional maturation process and its loss of function (LOF) accelerates functional maturation of SC-β cells. As a result, ZnT8 LOF improves glucose-stimulated insulin secretion (GSIS) and enhances proinsulin to insulin conversion efficiency in SC-β cells, both in vitro and in vivo, by releasing the negative feedback of zinc inhibition on insulin secretion. Furthermore, SC-β cells with ZnT8 LOF are resistant to metabolic stresses induced cell death, as lipotoxicity or glucotoxicity, displaying higher survival. Most importantly, transplantation of SLC30A8-/- SC-β cells into diabetic mice significantly improves glycemia restoration and SC-β cell survival with long-term stability. Therefore, our study offers an advanced cell replacement therapy for diabetes with both improved SC-β cell survival and function against metabolic stress.