Daily Endocrinology Research Analysis
Analyzed 28 papers and selected 3 impactful papers.
Summary
Three studies shape today’s endocrinology landscape: a Diabetologia mechanistic paper identifies ENPP2 as a regulator of beta-cell compensation via LPA–Akt/mTOR signaling; a large target-trial emulation links GLP-1 receptor agonists to lower mortality and fewer immune-related adverse events during immune checkpoint inhibitor therapy; and a national Indian study finds a strikingly high prevalence of gestational diabetes, supporting early universal screening.
Research Themes
- Beta-cell compensation mechanisms and therapeutic targets in obesity/diabetes
- Metabolic–oncology interface: GLP-1 RAs during immune checkpoint inhibitor therapy
- Maternal-fetal endocrinology: national burden and screening strategy for gestational diabetes
Selected Articles
1. Phosphodiesterase ENPP2, which is co-upregulated in obese and pregnant mice, is essential for islet beta cell compensation during obesity.
Single-cell and in vivo studies identify ENPP2 as a beta-cell pro-proliferative mediator that is upregulated in pregnancy and modestly in obesity. ENPP2 promotes beta-cell proliferation, reduces apoptosis, and enhances glucose-stimulated insulin secretion via LPA–LPAR2–Akt/mTOR signaling; its loss impairs beta-cell compensation on a high-fat diet. ENPP2 expression is reduced in diabetes and co-induced by estradiol and progesterone.
Impact: This work uncovers a tractable pathway linking reproductive hormones, lipid signaling, and beta-cell mass expansion, offering a mechanistic target to preserve beta-cell function in obesity and diabetes.
Clinical Implications: While preclinical, ENPP2/LPA–LPAR2–Akt/mTOR signaling represents a potential therapeutic axis to enhance beta-cell mass and function in obesity and possibly gestational or type 2 diabetes. Translation will require safety profiling and human islet validation.
Key Findings
- Beta-cell proliferation is the primary compensatory mechanism in both obesity and pregnancy, stronger in pregnancy by scRNA-seq.
- ENPP2 is highly upregulated in pregnant mouse beta cells and moderately in obesity; overexpression promotes proliferation and GSIS, while knockdown increases apoptosis in Min6 cells.
- Global knockout on high-fat diet causes insufficient beta-cell compensation; beta-cell ENPP2 overexpression enhances function in vivo.
- Mechanism involves LPA–LPAR2–Akt/mTOR signaling; ENPP2 is downregulated in diabetic mice and humans with type 2 diabetes and co-induced by estradiol plus progesterone.
Methodological Strengths
- Integrated multi-system approach: scRNA-seq, in vitro gain/loss-of-function, and in vivo transgenic and knockout models.
- Mechanistic pathway mapping with receptor specificity (LPAR2) and downstream signaling (Akt/mTOR).
Limitations
- Preclinical mouse and cell-line data; human functional validation is limited.
- Potential systemic effects in global knockout models and off-target consequences of LPA signaling were not fully addressed.
Future Directions: Evaluate pharmacologic modulation of the ENPP2–LPA–LPAR2 axis in diabetes models, validate in human islets, and assess long-term safety/efficacy and potential impacts in gestational diabetes.
AIMS/HYPOTHESIS: We aimed to identify key molecules that can moderately enhance the compensatory capacity of beta cells during obesity. METHODS: Single-cell RNA-seq was used to profile the RNA expression of islet cells from diet-induced obese mice and pregnant mice. The gene and protein expression levels of ectonucleotide pyrophosphatase/phosphodiesterase 2 (ENPP2) were verified by quantitative PCR and immunofluorescence, respectively. The roles of ENPP2 were investigated using gain-of-function and loss-of-function approaches in Min6 beta cells, global Enpp2-knockout mice and beta cell Enpp2-overexpressing transgenic (Enpp2-Tg) mice. RESULTS: Using single-cell RNA-seq, we demonstrated that proliferation is the primary and common mechanism for compensating for beta cell numbers during both mouse obesity and pregnancy, with proliferation being more pronounced in pregnancy than in obesity. Additionally, many differentially expressed genes were co-regulated in both conditions. Among these, the pro-proliferative phosphodiesterase ENPP2 showed the highest increase in beta cells of pregnant mice and a moderate increase in beta cells of obese mice. Overexpression or knockdown of ENPP2 in Min6 beta cells revealed that ENPP2 promoted beta cell proliferation, inhibited apoptosis and enhanced high-glucose-stimulated insulin secretion. These effects of ENPP2 were further validated in vivo using Enpp2-Tg mice. In Enpp2-knockout mice fed a high-fat diet, the deficiency of ENPP2 resulted in insufficient compensation of beta cells during obesity. The pro-proliferative role of ENPP2 in beta cells was mediated through the lysophosphatidic acid (LPA)-Akt/mammalian target of rapamycin (mTOR) signalling pathway via LPA receptor 2. However, the expression of ENPP2 was reduced in the mouse model of diabetes and in human participants with type 2 diabetes compared with non-diabetic control groups. Furthermore, ENPP2 was co-upregulated by a synergy of oestradiol and progesterone. CONCLUSIONS/INTERPRETATION: ENPP2 may serve as a key regulator in beta cell compensation during obesity, and modulating its levels in beta cells could be a potential therapeutic target for mitigating beta cell deterioration in diabetes.
2. GLP-1 receptor agonist use during immune checkpoint inhibitor therapy is associated with mortality and Immune-Related adverse events across cancer types in People with type 2 Diabetes: A Target-Trial emulation.
In a propensity-matched target-trial emulation (n=2,903 per group; 36-month follow-up), GLP-1 RA use at ICI initiation was associated with substantially lower mortality (HR 0.55; NNT 5), fewer hospitalizations, and fewer composite irAEs. Signals of increased diabetic retinopathy progression and non-arteritic anterior ischemic optic neuropathy suggest the need for ophthalmic monitoring.
Impact: This large, methodologically robust emulation bridges oncology and endocrinology, suggesting GLP-1 RAs may confer survival and safety advantages during ICI therapy in T2D, while flagging specific ocular risks.
Clinical Implications: Consider continuation/initiation of GLP-1 RAs in T2D patients starting ICIs, with proactive retinal and optic nerve monitoring; decisions should be individualized pending randomized trials.
Key Findings
- GLP-1 RA co-exposure reduced all-cause mortality (HR 0.55; 36-month ARD -16.41%; NNT 5).
- Hospitalizations and composite irAEs were lower (HR 0.76; ARD -7.06%; and 43.93% vs 51.51%, ARD -7.58%).
- Ophthalmic safety signals: higher diabetic retinopathy progression (HR 1.75) and NAION (HR 1.51).
- Findings were consistent across per-protocol, 90-day landmark, and semaglutide-only analyses.
Methodological Strengths
- Target-trial emulation with new-user, 1:1 propensity-score matching and intention-to-treat framework.
- Multiple prespecified sensitivity analyses (per-protocol, landmark, semaglutide-only) across a large, multi-institution EHR network.
Limitations
- Observational design risks residual confounding and confounding by indication (e.g., cancer stage, performance status).
- EHR-based outcome and exposure misclassification; ophthalmic events may be under- or over-captured.
Future Directions: Randomized trials to test GLP-1 RAs during ICI therapy, mechanistic studies on immune modulation, and prospective ophthalmic safety monitoring protocols.
AIMS: To evaluate whether Glucagon-like peptide-1 receptor agonist (GLP-1 RA) use at immune checkpoint inhibitor (ICI) start is associated with mortality, healthcare use, and immune-related adverse events in adults with type 2 diabetes (T2D). METHODS: A target-trial emulation was conducted in the TriNetX US Collaborative Network among adults with cancer and T2D starting an ICI, with or without overlapping GLP-1 RA at ICI start. A new-user 1:1 propensity-score-matched, intention-to-treat design yielded 2,903 per group and 36-month follow-up. Primary endpoint was all-cause mortality; key secondaries were hospitalization, and composite immune-related adverse events (irAEs). Prespecified per-protocol, 90-day landmark, and semaglutide-only analyses assessed robustness. RESULTS: GLP-1 RA co-exposure was associated with lower mortality (hazard ratio [HR] 0.55, 95 % CI 0.51-0.61; 36-month absolute risk difference [ARD] - 16.41 %; number needed to treat [NNT] 5). Hospitalization (HR 0.76; ARD - 7.06 %; NNT 11), and composite irAEs (43.93 % vs 51.51 %; ARD - 7.58 %; NNT 11) were also lower. Diabetic-retinopathy progression (HR 1.75; ARD + 2.71 %) and non-arteritic anterior ischemic optic neuropathy (HR 1.51) were higher; hypoglycaemia, acute kidney injury, and dehydration/orthostatic hypotension were lower. CONCLUSIONS: GLP-1 RA use during ICI therapy correlated with lower mortality, reduced acute care, fewer irAEs; ophthalmic signals warrant monitoring.
3. Prevalence of gestational diabetes mellitus in India: The ICMR-INDIAB national study (ICMR-INDIAB-24).
In a nationally representative analysis of 1,032 pregnant women, India’s weighted GDM prevalence was 22.4%, with similar urban–rural rates. Early GDM (before 20 weeks) was common (19.2%), and central India had the highest regional prevalence. Elevated systolic blood pressure and family history of diabetes were independent risk factors, supporting early universal screening.
Impact: Provides the first national estimate of GDM burden in India—including early-pregnancy prevalence—informing screening policy and resource planning in a high-risk population.
Clinical Implications: Implement universal GDM screening starting early in pregnancy, with attention to women with high systolic blood pressure or diabetes family history; plan region-specific resource allocation.
Key Findings
- Weighted national GDM prevalence was 22.4% (95% CI 16.7–28%), with no significant urban–rural difference (24.2% vs 21.6%).
- Early GDM (diagnosed <20 weeks) and late GDM (≥20 weeks) prevalences were 19.2% and 23.4%, respectively.
- Central India showed the highest prevalence (32.9%), while West India was lowest (16%).
- Higher systolic blood pressure and family history of diabetes were independently associated with GDM risk.
Methodological Strengths
- Nationally representative sampling with weighted estimates across regions and urban/rural strata.
- Use of OGTT and standardized NICE diagnostic criteria; early vs late GDM classification.
Limitations
- Cross-sectional design limits causal inference and does not capture perinatal outcomes.
- Modest sample size (n=1,032) for national estimates; single-timepoint testing may miss glycemic variability.
Future Directions: Prospective studies linking early vs late GDM to maternal–fetal outcomes, cost-effectiveness of early universal screening, and comparisons across diagnostic criteria.
Background & objectives The prevalence of gestational diabetes mellitus (GDM) is known to be high among South Asians. However, there is no national study on prevalence of GDM in India and few data comparing prevalence of GDM in early pregnancy (Early GDM) and late pregnancy (Late GDM). Methods This is an analysis of pregnant women who participated in the nationally representative Indian Council of Medical Research-India Diabetes (ICMR-INDIAB) study. Of the 1,206 pregnant women 1,032 who underwent oral glucose tolerance test (OGTT) or had fasting blood glucose measurement and did not have overt diabetes, were included in this study. GDM was diagnosed using the NICE criteria. GDM was classified as Early GDM if diagnosed before 20 wk of gestation and Late GDM if diagnosed ≥ 20 wk of gestation, Results The weighted national prevalence of GDM in India was 22.4 per cent (95% CI: 16.7-28%) with no significant urban rural differences (24.2% vs. 21.6%, NS). The prevalence of Early GDM and Late GDM were 19.2 per cent (9.8-28.7%) and 23.4 per cent (16.7-30.2%), respectively. Central India had the highest prevalence of GDM at 32.9 per cent (17.9-48%), and West India, the lowest at 16 per cent (3.1-29.3%). High systolic blood pressure and family history of diabetes were independently associated with risk of GDM. Interpretation & conclusions Nearly one in four pregnant women in India have GDM with regional variability. The prevalence of Early GDM is also high. Thus, there is a need for screening of all pregnant women for GDM starting in early pregnancy.