Daily Endocrinology Research Analysis
Analyzed 73 papers and selected 3 impactful papers.
Summary
Three impactful studies span mechanistic, population-scale, and clinical trial research in endocrinology and metabolism. Cryo-EM structures reveal how bivalent ligands antagonize the insulin receptor, guiding next-generation therapies for congenital hyperinsulinism; SNPdrug3D maps ~1.17 million protein-coding variants near drug-binding sites and builds a high-performing CYP variant predictor; and a double-blind RCT shows a lactobacilli-based probiotic does not prevent bone loss in early postmenopause.
Research Themes
- Receptor pharmacology and structural endocrinology
- Population-scale pharmacogenomics and variant interpretation
- Evidence-based appraisal of microbiome interventions in bone health
Selected Articles
1. Structural basis of insulin receptor antagonism by bivalent site 1-site 2 ligands S961 and Ins-AC-S2.
Cryo-EM structures demonstrate that S961 and Ins-AC-S2 antagonize the insulin receptor by stabilizing an inactive conformation. The order of site-1/site-2 modules dictates agonism versus antagonism, and distinct αCT and FnIII-2/insert domain interactions differentiate S961 from Ins-AC-S2, informing rational design of next-generation antagonists for congenital hyperinsulinism.
Impact: This study resolves the structural mechanism of insulin receptor antagonism and clarifies how bivalent ligand topology switches agonism to antagonism, a key step toward safe, potent therapies for congenital hyperinsulinism.
Clinical Implications: While preclinical, these structures enable structure-guided optimization of insulin receptor antagonists, potentially improving efficacy and safety profiles for congenital hyperinsulinism where therapeutic options are limited.
Key Findings
- Cryo-EM structures show S961 and Ins-AC-S2 bind and stabilize an inactive insulin receptor conformation.
- Agonist vs antagonist activity depends on the order of site-1 and site-2 modules in bivalent ligands.
- S961 and Ins-AC-S2 differ in αCT displacement/engagement and in interactions with receptor FnIII-2/insert domains.
Methodological Strengths
- High-resolution cryo-EM structural determination of ligand–receptor complexes
- Comparative analysis across bivalent ligands to link topology with functional outcome
Limitations
- Preclinical structural study without in vivo pharmacology or safety data
- Generalizability to other ligand classes remains to be tested
Future Directions: Use these structures to engineer optimized antagonists, validate in animal models of congenital hyperinsulinism, and explore structure–activity relationships across additional bivalent scaffolds.
Congenital hyperinsulinism is a rare genetic disease characterized by overproduction of insulin. One class of potential treatments is insulin receptor antagonists like S961 and Ins-AC-S2, which comprise segments for binding each of the two insulin-binding sites (site 1 and site 2) on the receptor. Notably, S597 - containing the same receptor binding segments as S961 but in the opposite order (site 2-site 1) - is an insulin receptor agonist rather than an antagonist. Using cryo-EM, we show how both S961 and Ins-AC-S2 bind an inactive conformation of the receptor, thereby explaining their antagonism. Furthermore, our structures reveal how agonist vs. antagonist activity is influenced by the order of site 1- and site 2-binding modules in bivalent ligands. Additionally, we show subtle differences between the receptor-binding mechanisms of S961 and Ins-AC-S2, which include displacement or engagement of αCT, and a binding interface between the Ins-AC-S2 insulin and the receptor FnIII-2/insert domains. These structural insights may inform development of next generation insulin receptor antagonists for treatment of congenital hyperinsulinism.
2. Genomic landscape of drug binding and pharmacogenetic variation across diverse populations using SNPdrug3D.
SNPdrug3D maps ~1.17 million missense variants proximal to drug-binding sites across the proteome from >80,000 individuals and experimentally validates selected effects on drug binding, including CYPs. A CYP-specific predictor achieves AUROC 0.9 (database-annotated) and 0.8 (assay-based), enabling population-aware variant interpretation and informing drug development and dosing.
Impact: This resource operationalizes structural pharmacogenomics at population scale and delivers a validated predictor for CYP variants, directly addressing a key bottleneck in variant interpretation and precision therapeutics.
Clinical Implications: Clinicians and pharmacologists can leverage SNPdrug3D to anticipate variant–drug interactions, particularly in CYPs, to prioritize confirmatory testing and tailor therapy in pharmacogenetically diverse populations.
Key Findings
- Mapped ~1.17 million missense variants near binding residues for ~6000 drugs across >80,000 individuals.
- Experimentally validated selected SNVs affecting drug binding in multiple target classes, including CYP enzymes.
- Developed a CYP-specific predictor outperforming existing tools (AUROC 0.9 database-annotated; 0.8 assay-based).
Methodological Strengths
- Large-scale integration of SG10K Health and gnomAD with structural mapping to drug–protein complexes
- Orthogonal experimental validation of predicted variant effects on binding
Limitations
- Focus on missense coding variants; limited coverage of regulatory and structural non-coding variation
- Functional validation limited to selected variants and targets; clinical utility not prospectively tested
Future Directions: Expand to non-coding/regulatory variants, broaden experimental validation, and prospectively evaluate clinical decision-support utility in pharmacogenetic implementation studies.
One of the promises of precision medicine is to understand and act on inter-individual genetic differences in drug responses. SNPdrug3D contains the complete genomic landscape of missense single nucleotide variants (SNV) across the human proteome and at a population-wide level that could affect drug binding. Here, we map SNVs in over 80,000 individuals from the Singapore SG10K Health and gnomAD cohorts to identify ~1.17 million variants mapped to residues near ~6000 bound drugs in protein-drug complexes and experimentally verify effects of selected SNVs, including previously uncharacterized variants, on drug binding in relevant proteins ranging from kinases to cytochrome P450s (CYPs). The latter led to a specific predictor for interpreting variants in the CYP family that outperforms existing tools in the prediction of pharmacogenetic effects based on database-annotated (AUROC = 0.9) or assay-based (AUROC = 0.8) test sets. By placing variants and drugs in structural contexts, SNPdrug3D aids drug development by pre-emptively flagging potential resistance sites based on population-specific variability.
3. Effects of 12-Month Probiotic Supplementation on Bone Mineral Density and Bone Turnover Markers in Early Postmenopausal Females: A Double-Blind Randomized Controlled Trial.
In a double-blind RCT of 114 early postmenopausal women, 12-month lactobacilli-based probiotic supplementation did not attenuate bone loss and was associated with a slightly greater decline in distal tibia total vBMD versus placebo. Secondary HR-pQCT, DXA, and biomarker outcomes did not demonstrate clinically meaningful benefit after multiplicity correction.
Impact: A well-controlled negative RCT tempers enthusiasm for probiotic-based skeletal preservation, redirecting practice toward proven lifestyle and pharmacologic strategies and highlighting the need for mechanism-informed designs.
Clinical Implications: This probiotic formulation should not be recommended as a standalone strategy to prevent early postmenopausal bone loss; clinicians should prioritize calcium/vitamin D optimization, weight-bearing exercise, fall prevention, and evidence-based pharmacotherapies when indicated.
Key Findings
- Probiotic supplementation led to a small but statistically significant greater decline in distal tibia total vBMD versus placebo over 12 months.
- Both groups experienced modest bone density declines; secondary HR-pQCT, DXA, and biomarker endpoints did not show meaningful benefit after multiplicity correction.
- The trial supports that this lactobacilli-based formulation does not attenuate early postmenopausal bone loss.
Methodological Strengths
- Double-blind, randomized, placebo-controlled design with ITT analysis
- High-resolution peripheral QCT as a sensitive primary endpoint and prespecified multiplicity control
Limitations
- Single probiotic formulation and dose; findings may not generalize to other strains or regimens
- Modest sample size and 12-month duration may miss longer-term or site-specific effects
Future Directions: Pursue mechanism-based microbiome interventions targeting bone pathways, assess alternative strains/doses, and integrate lifestyle or pharmacologic co-interventions in adequately powered, longer trials.
BACKGROUND: Early postmenopausal females experience rapid bone loss, and modulation of the gut-bone axis has been proposed as a preventive strategy. However, the role of probiotics relative to established lifestyle factors such as nutrition and physical activity remains unclear. OBJECTIVES: To evaluate whether 12 months of supplementation with a lactobacilli-based probiotic attenuates bone loss in early postmenopausal females. METHODS: In this double-blind, randomized, placebo-controlled trial, 114 females 1-8 years postmenopause were allocated to a daily probiotic (Lactiplantibacillus plantarum DSM15312, DSM15313, and Lacticaseibacillus paracasei DSM13434) or placebo. The primary outcome was change in distal tibia total volumetric bone mineral density (vBMD) assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT). Secondary outcomes included additional HR-pQCT parameters, areal BMD (aBMD) by DXA, and circulating biomarkers. Intention-to-treat analyses were conducted using linear mixed-effects models, adjusted for baseline covariates; secondary outcomes were corrected for multiple comparisons. RESULTS: A total of 114 participants were randomized, and all available data were included in the analyses. Baseline characteristics were broadly comparable. Over 12 months, both groups experienced modest declines in bone density. The primary analysis showed a modest but statistically significant greater decline in distal tibia total vBMD in the probiotic group compared with placebo (-3.7 mg HA/cm CONCLUSIONS: In early postmenopausal females, 12-month supplementation with a lactobacilli-based probiotic did not attenuate bone loss and was associated with a small but statistically significant greater reduction at the primary site. These findings do not support this probiotic formulation as a standalone intervention for skeletal preservation. CLINICAL TRIAL REGISTRATION NUMBER: ACTRN12621000810819 URL OF REGISTRATION: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=381292&isReview=true.