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Mammals adaptively regulate energy metabolism in response to environmental changes such as starvation and cold circumstances. Thioredoxin-interacting protein (Txnip), known as a redox regulator, serves as a nutrient sensor regulating energy homeostasis. Txnip is essential for mice to adapt to starvation, but its role in adapting to cold circumstances remains unclear. Here, we identified Txnip as a pivotal factor for maintaining non-shivering thermogenesis in mice. Txnip protein levels in brown adipose tissue (BAT) were upregulated by the acute cold exposure. Txnip-deficient (Txnip -/- ) mice acclimated to thermoneutrality (30°C) exhibited significant BAT enlargement and triglyceride accumulation with downregulation of BAT signature and metabolic gene expression. Upon acute cold exposure (5°C), Txnip -/- mice showed a rapid decline in BAT surface temperatures with the failure of increasing metabolic respiration, developing lethal hypothermia. The BAT dysfunction and cold susceptibility in Txnip -/- mice were corrected by acclimation to 16°C, protecting the mice from life-threatening hypothermia. Transcriptomic and metabolomic analysis using dissected BAT revealed that despite preserving glycolysis, the BAT of Txnip -/- mice failed to activate the catabolism of branched-chain amino acids and fatty acids in response to acute cold stress. These findings illustrate that Txnip is required for maintaining basal BAT function and ensuring cold-induced thermogenesis., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2025 The Authors. Published by Elsevier Inc. All rights reserved.)

Aim: How has the treatment policy changed since the introduction of health insurance coverage for assisted reproductive technology (ART) in Japan?, Methods: This study was conducted as a nationwide fact-finding survey to determine the current situation of ART treatment in Japan, the IZANAMI project. Among the 616 ART facilities across Japan, 283 (45.9%) that responded to the first (December 2021-February 2022) and second surveys (December 2023-January 2024) were recruited. Information on the clinical practices was collected via a questionnaire survey and analyzed., Results: Among the facilities with ≤200, 201-500, 501-1000, 1001-2000, and ≥2000 annual oocyte retrieval (OR) cycles, 93.9%, 88.7%, 75.0%, 69.7% and 42.9% performed ≥80% of their OR cycles using health insurance, respectively (p < 0.001), whereas 51.9%, 53.7%, 41.0%, 40.0% and 12.5% exhibited an increase in number of OR cycles, respectively (p = 0.03). Therefore, a significantly higher proportion of smaller-scale institutions than larger clinics had insured treatment and an increase in the number of OR cycles. Significantly more large clinics than small facilities selected mild stimulation, intracytoplasmic sperm injection, and freeze-all embryo cycle; however, no significant transitions were observed in the main policies for ART, regardless of facility size. However, the indication for mild stimulation significantly increased in normal to high responders, and the choice of ovarian stimulation protocol according to the patient's wishes was significantly reduced., Conclusions: Small-scale institutions were more likely to offer insured treatment and increase the number of OR cycles than large facilities; however, the main protocols did not significantly change., (© 2025 Japan Society of Obstetrics and Gynecology.)

Background: Embryologists are crucial in assisted reproductive technology (ART), yet their duties, education, and licensing requirements vary significantly across countries, complicating the determination of optimal staffing levels in ART laboratories. With anticipated advancements such as automation in ART laboratories, this review comprehensively analyzes factors necessary for appropriate future staffing., Main Findings: A comprehensive literature search was conducted using PubMed to identify relevant articles up to July 2024, employing keywords such as "embryologist," "staffing," and "certification." Articles were evaluated for content related to laboratory operations, and guidelines from five organizations regarding licensing and education were compared., Results: The review revealed significant international differences in embryologist certification, duties, and staffing recommendations. These disparities, along with the integration of advanced ART technologies and regulatory requirements, significantly impact future staffing needs in ART laboratories., Conclusion: The definitions of an ART cycle and required staffing levels vary across organizations, influenced by the certification and duties of embryologists in different countries. Adequate embryologist staffing is essential for ensuring laboratory quality control and impacting patient ART outcomes. As new technologies and automation reshape laboratory workflows, collaborative efforts among organizations, countries, and embryologist associations are essential for developing comprehensive educational curricula and determining appropriate staffing levels., Competing Interests: The authors declare no conflict of interest., (© 2025 The Author(s). Reproductive Medicine and Biology published by John Wiley & Sons Australia, Ltd on behalf of Japan Society for Reproductive Medicine.)