Daily Endocrinology Research Analysis
Analyzed 121 papers and selected 3 impactful papers.
Summary
Three high-impact studies advance endocrine science: (1) metabolic rewiring of propionate metabolism drives aldosterone excess in aldosterone-producing adenomas via methylmalonic acid–ROS signaling; (2) integrated islet epigenomics separates aging from type 2 diabetes signatures and yields a blood-based methylation score that improves diabetes classification; (3) a central prolactin–POMC neuron circuit suppresses hepatic lipogenesis, nominating a brain–liver target for MASLD.
Research Themes
- Adrenal tumor metabolism and redox control of steroidogenesis
- Islet epigenetics in aging versus type 2 diabetes
- Neuroendocrine brain–liver circuits in MASLD
Selected Articles
1. Reprogrammed Propionate Metabolism Alters Redox-Dependent Aldosterone Production.
Multi-omics and functional studies show aldosterone-producing adenomas accumulate methylmalonic acid via PCCA-driven propionate metabolism, elevating ROS and upregulating CYP11B2 to boost aldosterone. Gain- and loss-of-function experiments in adrenocortical cells and mouse adrenals establish a causal metabolite–redox axis for steroidogenesis.
Impact: This work uncovers a previously unrecognized metabolic–redox mechanism for aldosterone excess, nominating methylmalonic acid and propionate metabolism enzymes as actionable targets in primary aldosteronism.
Clinical Implications: If validated clinically, targeting propionate metabolism or methylmalonic acid (e.g., metabolic modulation, antioxidant strategies) could complement surgery/mineralocorticoid receptor blockade and guide biomarker-driven patient selection.
Key Findings
- Aldosterone-producing adenomas exhibited reprogrammed propionate metabolism with methylmalonic acid accumulation and PCCA upregulation.
- PCCA overexpression increased CYP11B2 expression and aldosterone production; PCCA silencing reduced both.
- Exogenous methylmalonic acid enhanced CYP11B2 and aldosterone in adrenocortical cells and female mouse adrenals.
- Mechanism involves methylmalonic acid–induced ROS, linking metabolism to redox-dependent steroidogenesis.
Methodological Strengths
- Integrated multi-omics (human adrenal and blood) with in vitro and in vivo functional validation.
- Bidirectional perturbation (overexpression/silencing) of PCCA and metabolite supplementation to test causality.
Limitations
- Detailed downstream signaling beyond ROS is truncated in the abstract and may require full-text clarification.
- Translational clinical validation (human outcomes, drug targeting) is not yet available.
Future Directions: Define the complete redox signaling cascade, assess sex differences, validate circulating methylmalonic acid as a biomarker, and test metabolic/redox interventions in preclinical PA models and early-phase trials.
BACKGROUND: Metabolic reprogramming is increasingly recognized as a key driver of endocrine tumor biology, yet how dysregulated metabolism promotes aldosterone excess in aldosterone-producing adenomas remains largely unclear. METHODS: Multiomics profiling of human adrenal and blood specimens was performed to identify metabolic reprogramming. Dysregulated genes and accumulation of intermediates in the propionate metabolism were validated in aldosterone-producing adenomas. Functional effects on aldosterone production were assessed in adrenocortical cells and mice. Key downstream molecules and pathways were examined through transcriptomics, mass spectrometry, and targeted functional assays. RESULTS: Aldosterone-producing adenomas exhibited reprogrammed propionate metabolism and accumulation of its byproduct methylmalonic acid, associated with upregulation of the upstream enzyme PCCA (propionyl-CoA carboxylase subunit A). In adrenocortical cells, PCCA overexpression increased CYP11B2 (aldosterone synthase) expression and aldosterone production, while its silencing had the opposite effects. In both adrenocortical cells and female mouse adrenals, methylmalonic acid promoted CYP11B2 expression and aldosterone production. Mechanistically, methylmalonic acid elevated reactive oxygen species, which triggered CONCLUSIONS: These findings identify a methylmalonic acid-oxidative stress-Ca
2. Epigenetic landscapes in human pancreatic islets reveal distinct drivers for adaptation to age and type 2 diabetes.
Integrated islet methylome–transcriptome analysis (n=144 donors) shows largely distinct age- versus T2D-associated CpGs and target genes. Age-linked promoter CpGs coordinate beta-cell function, while T2D CpGs reflect stress-related epigenetic drift. A blood methylation score based on age-linked CpGs correlates with insulin secretion and, combined with genetic risk, improves diabetes classification (AUC 0.91).
Impact: This study disentangles aging from diabetic epigenetic drivers in human islets and proposes a clinically tractable blood methylation risk score that augments genetic classification.
Clinical Implications: Blood-based methylation profiling could improve risk stratification and mechanistic phenotyping beyond genetics, informing precision prevention or monitoring of beta-cell dysfunction.
Key Findings
- Identified 996 age- and 902 T2D-associated CpGs in human islets with minimal overlap.
- Age-linked CpGs enriched in promoters co-regulate beta-cell functional modules; T2D-linked CpGs enriched in enhancer/non-regulatory regions suggest stress-induced drift.
- Mendelian randomization supports causality for age-associated CpGs regulating KLHL42.
- A blood methylation risk score based on age-linked CpGs correlates with insulin secretion and improves T2D classification with genetics (AUC 0.91).
Methodological Strengths
- Multi-omic integration (DNA methylation, transcriptomics, genotyping) in primary human islets.
- Use of Mendelian randomization and development of an externally relevant blood methylation score.
Limitations
- Cross-sectional donor data limit causal inference for disease progression.
- Clinical utility of the methylation score requires prospective validation and standardization.
Future Directions: Prospectively test the methylation score in diverse populations, integrate with proteomics/secretomes, and evaluate modulation of age- versus T2D-linked CpGs in interventional studies.
Age is the strongest risk factor for type 2 diabetes, yet their independent contribution to pancreatic islet dysfunction remains unclear. We integrate DNA methylation, transcriptomic, and genotyping data from 144 islet donors. We identify 996 age- and 902 T2D-associated CpGs with minimal overlap, and 251 age- and 310 diabetes CpG target genes, usually distant from the CpG. Age-linked CpGs are enriched in promoters, form co-regulated gene modules, link to beta-cell function, including insulin secretion. Diabetes-associated CpGs are enriched in enhancer/non-regulatory regions, and modules suggest stress-induced epigenetic drift. CpG-gene associations are independent of genetic variation. Mendelian randomisation supports a causal role for age-associated CpGs regulating KLHL42, a T2D GWAS locus. A blood-based methylation risk score based on age-linked CpGs correlates with insulin secretion and improves diabetes classification when combined with genetic risk (AUC = 0.91). Altogether, age is associated with a coordinated epigenetic programme, whereas diabetes links to a heterogeneous, stress-related epigenetic signature.
3. Prolactin acts on proopiomelanocortin neurons to regulate hepatic lipid metabolism.
Central PRL signaling activates arcuate POMC neurons, increases hepatic sympathetic outflow, and suppresses FASN-mediated de novo lipogenesis, protecting against steatosis in HFD-fed mice. POMC-specific PRLR loss abolishes these anti-steatotic effects, and intracerebroventricular PRL acts faster than peripheral dosing.
Impact: Reveals a hormone–neuron–liver circuit linking pituitary PRL to hepatic lipid metabolism, offering a mechanistically precise target for MASLD beyond peripheral-only approaches.
Clinical Implications: Central PRL pathways or selective POMC neuronal PRLR signaling could be explored to modulate hepatic lipogenesis; biomarkers of central PRL tone may help stratify MASLD patients.
Key Findings
- PRL deficiency exacerbated hepatic steatosis in HFD-fed mice; intracerebroventricular PRL rapidly alleviated steatosis versus peripheral PRL.
- PRLR is highly expressed on arcuate POMC neurons; PRL increases their excitability and activity.
- POMC neuron–specific PRLR knockout abrogated PRL’s anti-steatotic effects and worsened lipid accumulation.
- Central PRL enhanced hepatic sympathetic outflow to suppress FASN-mediated de novo lipogenesis.
Methodological Strengths
- Convergent genetics (PRL−/−; POMC-specific PRLR KO), targeted knockdown, central vs peripheral hormone delivery.
- Multimodal readouts (electrophysiology, RNA-seq, denervation, primary hepatocytes) to define mechanism and circuit.
Limitations
- Mouse-focused preclinical study; human validation of central PRL–POMC–liver axis is needed.
- Therapeutic translatability (drug targets, safety of central modulation) remains to be demonstrated.
Future Directions: Map downstream hepatic sympathetic nodes and peripheral biomarkers of central PRL tone; evaluate translational pharmacology that selectively engages POMC PRLR signaling.
OBJECTIVE: To elucidate the central mechanism of pituitary-derived prolactin (PRL) in hepatic lipid homeostasis and identify therapeutic targets for metabolic dysfunction-associated fatty liver disease (MASLD). METHODS: High-fat diet (HFD)-fed mice induced MASLD. PRL⁻/⁻ mice, POMC neuron-specific PRL receptor (PRLR) conditional knockout mice, AAV-mediated PRLR knockdown, and central/peripheral PRL administration were used to explore PRL's central regulatory role. Metabolic phenotyping, histological/biochemical assays, immunofluorescence, electrophysiology, RNA-seq, 6-OHDA-induced sympathetic denervation, and primary hepatocyte experiments were performed to evaluate phenotypes, neuronal activity and underlying mechanisms. RESULTS: PRL deficiency exacerbated HFD-induced hepatic lipid deposition, and central intracerebroventricular PRL alleviated hepatic steatosis in HFD-fed PRL⁻/⁻ and wild-type mice more rapidly than peripheral intraperitoneal PRL. PRLR was highly expressed in hypothalamic arcuate nucleus POMC neurons, which PRL selectively activated by enhancing neuronal excitability. POMC-specific PRLR knockout abrogated PRL's anti-steatotic effects and aggravated HFD-induced hepatic lipid accumulation. Mechanistically, central PRL enhanced hepatic sympathetic outflow to suppress de novo lipogenesis via the FASN pathway. CONCLUSION: PRL acts on hypothalamic POMC neurons to enhance hepatic sympathetic activity, suppressing FASN-mediated lipogenesis and maintaining lipid homeostasis. This novel PRL-driven brain-liver circuit highlights central PRL signaling as a promising MASLD therapeutic target.