Daily Endocrinology Research Analysis
Analyzed 48 papers and selected 3 impactful papers.
Summary
Three high-impact endocrinology papers stood out today: a Nature Communications mechanistic study uncovers a novel post-translational HMGylation of PPARγ linking leucine catabolism to brown/beige fat thermogenesis; an international Delphi consensus standardizes definitions and thresholds for weight recurrence after bariatric surgery; and a large multinational registry analysis shows robust glycemic benefits of automated insulin delivery in children with type 1 diabetes.
Research Themes
- Amino acid metabolism and adipose thermogenesis mechanisms
- Standardization of post-bariatric outcomes and care pathways
- Real-world effectiveness of diabetes technologies in pediatrics
Selected Articles
1. Leucine catabolic enzyme AUH regulates BAT thermogenesis via PPARγ HMGylation and RNA-binding function in male mice.
This mechanistic study identifies AUH as a dual-function regulator of thermogenesis: via metabolite-driven HMGylation of PPARγ (K386) that boosts UCP1 transcription and via RNA-binding that stabilizes Ucp1 mRNA. AUH overexpression promotes browning and protects male mice from diet-induced obesity, linking leucine catabolism to adipose thermogenesis.
Impact: It discovers a previously unrecognized post-translational modification (HMGylation) of PPARγ that directly controls thermogenesis, offering a new mechanistic axis and potential target for obesity therapies.
Clinical Implications: While preclinical, modulating AUH activity or PPARγ HMGylation could be explored to enhance brown/beige fat function and energy expenditure in obesity and metabolic disease.
Key Findings
- HMG-CoA mediates PPARγ HMGylation at lysine 386, enhancing UCP1 transcription and thermogenesis.
- AUH binds and stabilizes Ucp1 mRNA, providing a second, RNA-mediated mechanism to increase UCP1.
- AUH overexpression induces browning and protects male mice from high-fat diet–induced obesity; AUH expression in human WAT inversely correlates with adiposity.
Methodological Strengths
- Integrated in vitro and in vivo validation with gain- and loss-of-function approaches.
- Discovery and functional mapping of a novel post-translational modification (PPARγ HMGylation) with human adipose correlation.
Limitations
- Predominant use of male mice may limit generalizability to females.
- Translational applicability and safety of targeting AUH/PPARγ HMGylation remain untested in humans.
Future Directions: Validate PPARγ HMGylation in human thermogenic adipocytes, define sex-specific effects, and develop pharmacologic modulators of AUH/HMG-CoA flux to test metabolic efficacy and safety.
A strong association between leucine and obesity has been well established; however, the role of leucine catabolic enzymes in adipose tissue remains largely unknown. Here, we show that knockdown of the leucine catabolic enzyme AU RNA-binding methylglutaconyl-CoA hydratase (AUH) in brown adipocytes reduces thermogenesis, while AUH over-expression has the opposite effect both in vivo and in vitro. Mechanistically, AUH partially promotes uncoupling protein 1 (UCP1) expression through its metabolite 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA). HMG-CoA directly HMGylates peroxisome proliferator-activated receptor gamma (PPARγ) on lysine 386, enhancing its transcriptional activity to increase UCP1 expression. In addition, AUH binds to and stabilizes Ucp1 mRNA via its RNA-binding function. Moreover, we discovered that AUH promotes white adipose tissue browning; AUH expression in human white adipose tissue is inversely correlated with adiposity, and over-expression of AUH in adipose tissue protects male mice against high-fat diet-induced obesity. Collectively, these results provide new insights into the crosstalk between amino acid metabolism and thermogenesis and identify a novel post-translational modification of PPARγ.
2. International expert consensus on definitions and management of weight recurrence and suboptimal response after metabolic and bariatric surgery: a Delphi study.
An international modified Delphi study (66 experts, 2 rounds) reached consensus on core terminology and metrics for post-bariatric outcomes, endorsing “suboptimal” and %TWL, and defining nonresponse (<10% TWL at 12 months) and recurrent weight gain (>25% of lost weight from nadir). Agreement on provider roles (including antiobesity medications) and conservative management was unanimous or strong.
Impact: It closes a critical standardization gap, enabling comparable research and coordinated multidisciplinary care for post-bariatric weight trajectories.
Clinical Implications: Clinicians can adopt %TWL and agreed thresholds to define nonresponse and weight recurrence, structure follow-up pathways, and appropriately integrate antiobesity medications, endoscopy, or surgical revisions.
Key Findings
- Terminology: “Suboptimal” preferred for inadequate outcomes (89.5% agreement); %TWL endorsed as the primary metric (94.6%).
- Thresholds: Surgical nonresponse defined as <10% TWL at 12 months (73.0%); recurrent weight gain defined as >25% of lost weight from nadir (70.3%).
- Roles: Unanimous agreement that specialists can prescribe antiobesity medications; conservative management items achieved the highest consensus (80.9%), with substantial inter-rater reliability (AC1 = 0.70).
Methodological Strengths
- Predefined consensus threshold with two-round modified Delphi across five disciplines and international settings.
- Assessment of inter-rater reliability (Gwet’s AC1) and comprehensive coverage (164-item instrument).
Limitations
- Moderate response rates (~55%) and expert selection may introduce bias.
- Consensus on quantitative thresholds was incomplete and lacks prospective outcome validation.
Future Directions: Prospectively validate agreed thresholds against clinical outcomes, refine subgroups, and integrate consensus into guideline updates and reimbursement policies.
BACKGROUND: Weight recurrence and suboptimal response after metabolic and bariatric surgery (MBS) lack standardized definitions and management approaches, creating barriers to evidence-based treatment decisions and coordinated care across multiple specialties. OBJECTIVES: To establish international expert consensus on terminology, diagnostic approaches, and management strategies for suboptimal response and weight recurrence after MBS. SETTING: International Delphi study across multiple countries and health care systems. METHODS: A two-round modified Delphi study was conducted with 66 international experts across five specialties (MBS, obesity medicine, gastroenterology, endocrinology, dietetics and nutrition, and psychology). A 164-item questionnaire was developed, spanning seven dimensions: conservative management, diagnostic methods, endoscopic interventions, quantitative thresholds, risk factors, surgical interventions, and terminology. Consensus was defined a priori as ≥70% agreement. Inter-rater reliability was assessed using Gwet's AC1 coefficient. RESULTS: Response rates were 54.5% (Round 1) and 57.6% (Round 2). Consensus achievement improved significantly between rounds (26.2% to 40.9% of items). Experts reached unanimous agreement on core management principles including individualized patient care (100%) and the appropriateness of specialists prescribing antiobesity medications (100%). Strong consensus emerged on standardized terminology with "suboptimal" as the preferred term (89.5%) and %TWL as the optimal measurement approach (94.6). For quantitative thresholds, consensus was achieved on surgical nonresponse defined as <10% TWL at 12 months (73.0%), recurrent weight gain as >25% of lost weight from nadir (70.3%), and a 10% change in %EWL from nadir as normal physiologic response (83.8%). Conservative management items achieved the highest consensus rates (80.9%) while quantitative threshold items require additional research (28.1%). Inter-rater reliability improved across all domains, with conservative management achieving substantial agreement (AC1 = .70). CONCLUSION: Expert consensus was achieved on fundamental principles of postbariatric care, including preferred terminology, measurement metrics, and provider roles. These recommendations address important gaps in clinical practice standardization.
3. Automated insulin delivery use in children and adolescents with type 1 diabetes across the world.
In 2,170 children/adolescents across 29 countries, AID initiation improved HbA1c, increased time in range and tight target range, reduced mean sensor glucose and variability, and decreased time below range, without increasing total daily insulin dose.
Impact: Provides large-scale, multinational, real-world pediatric evidence supporting AID effectiveness, informing device adoption and reimbursement decisions.
Clinical Implications: Supports broader AID adoption in pediatric T1D to improve glycemic metrics and reduce hypoglycemia without increasing insulin dose; encourages health systems to facilitate access and training.
Key Findings
- AID increased time in target range (70–180 mg/dL) and tight target range (70–140 mg/dL).
- Mean sensor glucose and glucose variability decreased; time below range (<70 mg/dL) was reduced.
- HbA1c improved without a significant change in total daily insulin dose.
Methodological Strengths
- Large, multinational registry with within-person pre–post comparison over 24 months.
- Multiple glycemic endpoints from continuous glucose monitoring, increasing robustness.
Limitations
- Observational design without randomization; potential confounding and selection bias.
- Heterogeneity in AID systems and clinical practices across centers and countries.
Future Directions: Head-to-head comparisons of AID algorithms in pediatrics, equity and access analyses, and long-term outcomes on complications and quality of life.
AIMS: Automated insulin delivery (AID) systems are increasingly used in type 1 diabetes (T1D) management, yet large-scale real-world evidence in pediatric populations remains limited. This study assessed the impact of AID therapy on glycemic outcomes in children and adolescents with T1D using data from the international SWEET registry. METHODS: We performed an observational comparative study using two treatment periods (12 months before and after AID initiation). Data were obtained from the SWEET database, with 53 centers across 29 countries contributing eligible cases. Participants were children and adolescents (≤18 years) with T1D who initiated AID therapy between 2014 and 2022. Primary endpoints included HbA1c, mean sensor glucose, and percentages of time spent in predefined glycemic ranges. RESULTS: A total of 2,170 participants were included. AID therapy was associated with significant improvements in glycemic control. Time in the target range (70-180 mg/dL) and tight target range (70-140 mg/dL) increased, while mean sensor glucose and glucose variability decreased. Time below range (<70 mg/dL) was reduced. HbA1c improved without a significant change in total daily insulin dose. CONCLUSIONS: In this large multinational real-world cohort, AID therapy significantly improved glycemic outcomes and reduced hypoglycemia in children and adolescents with T1D. These findings support the effectiveness of AID systems across diverse clinical settings and underscore their value in pediatric diabetes care.