Daily Endocrinology Research Analysis
Analyzed 56 papers and selected 3 impactful papers.
Summary
Analyzed 56 papers and selected 3 impactful articles.
Selected Articles
1. Oxytocin signaling in adipocytes is required for normal milk fat production.
Using adipocyte-specific OXTR knockout dams, the study demonstrates that oxytocin signaling in adipocytes drives lipolysis to supply milk triglycerides necessary for neonatal growth. This uncovers an endocrine-adipose axis essential for lactation beyond the classical mammary epithelial synthesis pathways.
Impact: Reveals a previously unrecognized endocrine control point for milk fat production with implications for lactation failure and neonatal nutrition.
Clinical Implications: Suggests potential therapeutic avenues to support lactation by modulating oxytocin–adipocyte pathways or adipose lipolysis in mothers with inadequate milk fat. Encourages assessment of maternal adipose function in lactation problems.
Key Findings
- Adipocyte-specific deletion of OXTR impairs the supply of milk triglycerides.
- Oxytocin signaling promotes adipose lipolysis to sustain neonatal growth.
- Identifies an endocrine–adipose axis critical for lactation beyond mammary de novo lipogenesis.
Methodological Strengths
- Cell type–specific genetic manipulation (adipocyte-specific OXTR knockout) establishes causality.
- Physiological readouts link molecular signaling to neonatal growth and milk composition.
Limitations
- Preclinical mouse model; human translational relevance requires confirmation.
- Mechanistic quantification of lipid fluxes and pathway intermediates is not detailed in the abstract.
Future Directions: Validate adipocyte OXTR signaling in human lactation disorders; test pharmacologic or behavioral interventions that enhance adipose lipolysis without compromising maternal metabolism.
Milk triglycerides, a crucial nutrient source for newborn mammals, can be derived from adipose lipolysis, dietary sources, or de novo synthesis in mammary epithelial cells (MECs). Here, we identify a critical role for the neuropeptide oxytocin (OXT) in providing milk triglyceride needed to sustain neonatal growth, mediated by its actions on adipose lipolysis. Dams lacking OXT receptors (OXTRs) specifically in adipocytes (Oxtr
2. Hepatocyte DDIT4 aggravates MASH progression through GPX4-mediated ferroptosis.
DDIT4 is upregulated in human and murine MASH and drives disease via GPX4 suppression and impaired mitochondrial localization, activating ferroptosis. Hepatocyte-specific genetics establish causality, and quercetagetin is identified as a DDIT4-binding small molecule that ameliorates steatosis, inflammation, and fibrosis in MASH mice.
Impact: Identifies a concrete ferroptosis pathway node linking stress signaling (DDIT4/mTORC1) to antioxidant defense (GPX4) in MASH and nominates a tractable small-molecule target.
Clinical Implications: Positions DDIT4 as a therapeutic target and supports preclinical development of DDIT4 modulators (e.g., quercetagetin) and biomarker strategies to identify ferroptosis-driven MASH.
Key Findings
- DDIT4 is elevated in MASH and correlates with disease severity in humans and mice.
- Hepatocyte-specific DDIT4 overexpression aggravates, while deletion alleviates, ferroptosis and MASH progression.
- Mechanism: DDIT4 suppresses GPX4 via mTORC1 and blocks TOM22-mediated mitochondrial GPX4 translocation, activating ferroptosis.
- Quercetagetin binds DDIT4 (docking and SPR) and improves steatosis, inflammation, and fibrosis in MASH mice.
Methodological Strengths
- Multi-tiered mechanistic validation: human data, hepatocyte-specific genetic models, RNA-seq, IP-MS, docking, and SPR.
- Use of multiple diet-induced MASH mouse models enhances generalizability.
Limitations
- Preclinical evidence; no human interventional validation of DDIT4 targeting.
- Potential off-target or pleiotropic effects of quercetagetin require profiling.
Future Directions: Develop selective DDIT4 modulators with pharmacokinetic optimization; evaluate ferroptosis biomarkers in patient stratification; initiate early-phase trials in biopsy-proven MASH.
BACKGROUND & AIMS: Metabolic dysfunction-associated steatohepatitis (MASH) is a progressive liver disease with limited therapeutic options, and the role of ferroptosis in its pathogenesis remains to be fully understood. In this study, we aimed to investigate the action of DNA damage-inducible transcript 4 (DDIT4) in the ferroptosis and regulation of MASH progression. METHODS: The Gene Expression Omnibus database of MASH mice models and ferroptosis database were used to identify crucial ferroptosis related genes in MASH. Hepatic DDIT4 expression was detected in MASH patients, mouse models and hepatocytes. The functional role of DDIT4 was assessed in different diet induced MASH mice models with gene hepatocyte-specific over-expression or conditional knockout. RNA-sequencing and immunoprecipitation-mass spectrometry (IP-MS) were performed to determine DDIT4 interacting proteins. Molecular docking was used to explore the potential compound targeting DDIT4. RESULTS: We have discovered significantly elevated DDIT4 levels in mice and patients with MASH, which were positively correlated with MASH severity. Hepatocyte-specific over-expression of DDIT4 aggravated ferroptosis and MASH progression, while DDIT4 deletion alleviated ferroptosis and MASH progression. Mechanistically, DDIT4 decreased glutathione peroxidase 4 (GPX4) expression in an mTORC1 dependent manner. Additionally, DDIT4 interacted with cytosolic GPX4 and inhibited TOM22-mediated mitochondrial translocation, resulting in mitochondrial GPX4 reduction and ferroptosis activation. Importantly, through molecular docking and surface plasmon resonance (SPR), we have identified quercetagetin, a natural flavonoid, as a potential DDIT4-targeting compound. Administration of quercetagetin alleviated hepatic steatosis, inflammation, and fibrosis in MASH mice. CONCLUSIONS: Our study establishes the DDIT4-GPX4-ferroptosis axis as a new regulatory node in MASH progression and highlights DDIT4 as a potential therapeutic target for MASH.
3. An optimized protocol for efficient derivation of pancreatic islets from multiple human pluripotent stem cell lines.
A standardized, cross-line protocol shortens the pancreatic progenitor stage, induces endocrine progenitors on laminin-521, and leverages self-aggregation to purge non-endocrine cells. The resulting SC-islets are glucose-responsive in vitro and restore euglycemia in diabetic mice while being free of non-endocrine contaminants by single-cell profiling.
Impact: Addresses a central bottleneck in T1D cell therapy by delivering a reproducible method across diverse hPSC lines with in vivo functional rescue.
Clinical Implications: Facilitates scalable manufacturing of safer, purer SC-islets for transplantation, reducing risks from proliferative/non-endocrine contaminants and enabling standardization for clinical translation.
Key Findings
- Protocol works across eight distinct hPSC lines to generate functional SC-islets.
- Shortening the pancreatic progenitor stage and inducing EPs on laminin-521 improves lineage specification.
- Self-aggregation efficiently removes proliferative and non-endocrine cells, yielding glucose-responsive islets.
- Transplanted SC-islets mature in vivo and normalize glycemia; single-cell analysis confirms absence of non-endocrine populations.
Methodological Strengths
- Validation across multiple hPSC lines enhances robustness and reproducibility.
- In vivo functional rescue and single-cell transcriptomics provide stringent quality confirmation.
Limitations
- Preclinical transplantation site (anterior chamber of the eye) differs from intended clinical sites.
- Long-term graft durability, immunogenicity, and manufacturing scale-up remain to be addressed.
Future Directions: Assess long-term function and safety in large animals, optimize encapsulation/immune protection, and develop GMP-scale manufacturing and release criteria.
The success of cell therapy for type 1 diabetes (T1D) depends on reliable differentiation of stem cells into functional pancreatic islets. Current protocols produce stem cell-derived islets (SC-islets) that contain non-endocrine cells and show limited maturity. We developed a robust protocol that generates functional SC-islets from all eight tested human pluripotent stem cell (hPSC) lines. Differentiation to the endocrine progenitor (EP) stage on 2D laminin-521 is improved by shortening the prior pancreatic progenitor (PP) stage. Notably, allowing EP cells to self-aggregate efficiently removes proliferative and non-endocrine cells. Subsequent suspension culture yields SC-islets with strong glucose responsiveness in vitro. After transplantation into the anterior chamber of the eye of diabetic mice, SC-islets further mature and restore normal glycemic control. Single-cell analyses show that the SC-islets are free of non-endocrine cell populations before and after transplantation. This protocol enables production of highly functional SC-islets suitable for T1D cell therapy.