Objective: The essential role of raptor/mTORC1 signaling in β-cell survival and insulin processing has been recently demonstrated using raptor knock-out models. Our aim was to evaluate the role of mTORC1 function in adaptation of β-cells to insulin resistant state.
Method: Here, we use mice with heterozygous deletion of raptor in β-cells (βra) to assess whether reduced mTORC1 function is critical for β-cell function in normal conditions or during β-cell adaptation to high-fat diet (HFD).
Results: Deletion of a raptor allele in β-cells showed no differences at the metabolic level, islets morphology, or β-cell function in mice fed regular chow. Surprisingly, deletion of only one allele of raptor increases apoptosis without altering proliferation rate and is sufficient to impair insulin secretion when fed a HFD. This is accompanied by reduced levels of critical β-cell genes like Ins1, MafA, Ucn3, Glut2, Glp1r, and specially PDX1 suggesting an improper β-cell adaptation to HFD.
Conclusion: This study identifies that raptor levels play a key role in maintaining PDX1 levels and β-cell function during the adaptation of β-cell to HFD. Finally, we identified that Raptor levels regulate PDX1 levels and β-cell function during β-cell adaptation to HFD by reduction of the mTORC1-mediated negative feedback and activation of the AKT/FOXA2/PDX1 axis. We suggest that Raptor levels are critical to maintaining PDX1 levels and β-cell function in conditions of insulin resistance in male mice.
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http://dx.doi.org/10.1016/j.molmet.2023.101769 | DOI Listing |
J Sci Food Agric
January 2025
Food Science and Technology Program, Department of Life Sciences, BNU-HKBU United International College, Zhuhai, China.
Artificial sweeteners have emerged as popular alternatives to traditional sweeteners, driven by the growing concern over sugar consumption and its associated rise in obesity and metabolic disorders. Despite their widespread use, the safety and health implications of artificial sweeteners remain a topic of debate, with conflicting evidence contributing to uncertainty about their long-term effects. This review synthesizes current scientific evidence regarding the impact of artificial sweeteners on gut microbiota and gastrointestinal health.
View Article and Find Full Text PDFNanoscale
January 2025
Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Pr. 47, Moscow 119991, Russia.
Adapting biological systems for nanoparticle synthesis opens an orthogonal Green direction in nanoscience by reducing the reliance on harsh chemicals and energy-intensive procedures. This study addresses the challenge of efficient catalyst preparation for organic synthesis, focusing on the rapid formation of palladium (Pd) nanoparticles using bacterial cells as a renewable and eco-friendly support. The preparation of catalytically active nanoparticles on the bacterium VKM B-3302 represents a more suitable approach to increase the reaction efficiency due to its resistance to metal salts.
View Article and Find Full Text PDFInt J Surg
January 2025
Senior researcher and lecturer at the Master Specialized Physical Therapy programs at Avans+, Breda, The Netherlands.
Introduction: Spastic Cerebral Palsy (CP) is a major cause of movement disorders in pediatric rehabilitation. Current treatments are often invasive and may lead to substantial discomfort. Extracorporeal shockwave therapy (ESWT) presents a potential alternative, offering a less invasive approach with a reduced side effect profile.
View Article and Find Full Text PDFJ Cardiovasc Surg (Torino)
February 2025
Department of Vascular Surgery, AZ Sint Blasius, Dendermonde, Belgium.
Background: Due to the heterogeneity of literature findings, stent type selection for the endovascular treatment of complex aorto-iliac occlusive disease remains challenging. The BELSTREAM study, a physician-initiated, prospective, multicenter, single-arm study, aims to report the safety and efficacy of the balloon expandable LifeStream Peripheral Stent Graft System (BD, Tempe, Arizona, USA) for the treatment of complex TASC C and D aorto-iliac artery lesions.
Methods: Seventy patients and 133 lesions were included at six Belgian institutions.
J Cardiovasc Surg (Torino)
February 2025
Department of Vascular Surgery, ASST Settelaghi Universitary Teaching Hospital, University of Insubria, Varese, Italy.
Optimizing the longevity of vascular access in hemodialysis patients remains a critical aspect of patient care, given the significant role of arteriovenous fistulas (AVFs) and arteriovenous grafts (AVGs) in enabling effective dialysis. Vascular access complications, such as stenosis, thrombosis, and cannulation-related damage, continue to challenge both the functionality and the sustainability of these access points. Recent advancements underscore the importance of a robust follow-up strategy, integrating clinical evaluations with diagnostic tools like color Doppler ultrasound (CDU) and emerging interventional approaches such as drug-coated balloon (DCB) angioplasty.
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