A Practical Review of C-Peptide Testing in Diabetes

Glucose Disorders

Glucose disorders are the most common endocrine condition in the primary care setting. The conditions overlap and are better viewed as a spectrum rather than discrete entities. Multiple treatment agents are now available for diabetes mellitus which include long-acting and short-acting insulins and medications targeting the various pathways of diabetes including liver gluconeogenesis, increasing peripheral insulin sensitivity, stimulating pancreatic insulin production, eliminating glucose renally, decreasing carbohydrate gastrointestinal absorption, and targeting the body's incretin system. Various endocrine conditions can cause secondary hyperglycemia or hypoglycemia. Medications and physiologic stress can affect glucose levels. Genetic syndromes causing enzyme deficiencies underlie a small portion of glucose disorders.

Early onset type 2 diabetes mellitus: an update

The incidence and prevalence of type 2 diabetes mellitus (T2DM) in young individuals (aged <40 years) have significantly increased in recent years, approximating two to threefold increase in the respective rates. Numerous risk factors including severe obesity, family history, ethnicity, maternal diabetes or gestational diabetes, and female sex contribute to a younger age of onset. In terms of pathogenesis, impaired insulin secretion is the key operating mechanism, alongside with ectopic adiposity-related insulin resistance. T2DM diagnosis in a young adult requires the exclusion of type 1 diabetes mellitus (T1DM), latent autoimmune diabetes of adults (LADA) and maturity-onset diabetes of the young (MODY). The establishment of such diagnosis is critical for prognosis, because early-onset T2DM is associated with rapid deterioration in pancreatic β-cell secretory function leading to earlier initiation of insulin therapy. Furthermore, mortality and lifetime risk of developing complications, especially microvascular, is increased in these patients compared to both later-onset T2DM and T1DM patients; also, the latter are often developed earlier in the course of disease. The management of early-onset T2DM follows the same guidelines as in later-onset T2DM; yet patients aged 18-39 years are underrepresented in the big clinical trials on which the development of guidelines is based. Finally, young people with T2DM face significant challenges associated with social determinants, which compromise their adherence to therapy and induce diabetes distress. Future research focusing on the pathogenesis of β-cell decline and complications, as well as on specific treatment shall lead to better understanding and management of early-onset T2DM.

Diabetes Management Based on the Phenotype and Stage of the Disease: An Expert Proposal from the AGORA Diabetes Collaborative Group

Diabetes is a complex and rapidly growing disease with heterogeneous clinical presentations. Recent advances in molecular and genetic technologies have led to the identification of various subtypes of diabetes. These advancements offer the potential for a more precise, individualized approach to treatment, known as precision medicine. Recognizing high-risk phenotypes and intervening early and intensively is crucial. A staging system for type 1 diabetes has been proposed and accepted globally. In this article, we will explore the different methods for categorizing and classifying type 2 diabetes (T2D) based on clinical characteristics, progression patterns, risk of complications, and the use of molecular techniques for patient grouping. We, as a team of experts, will also present an easy-to-follow treatment plan and guidance for non-specialists, particularly primary care physicians, that integrates the classification and staging of diabetes. This will help ensure that the most suitable therapy is applied to the different types of T2D at each stage of the disease's progression.

Glycemic variability in chronic calcific pancreatitis with diabetes mellitus and its possible determinants

AIMS

To study glycemic patterns and variability in patients with pancreatic diabetes or type 3c Diabetes mellitus (DM) due to chronic pancreatitis and its subtypes and assess the role of pancreatic enzyme replacement therapy (ERT) in modulating glycemic variability.

METHODS

Patients having type 3c DM due to chronic pancreatitis, and on insulin underwent Flash continuous-glucose-monitoring (CGM) for 14 days. Parameters were compared between patients with fibrocalculous pancreatic diabetes (FCPD) and non-FCPD-chronic calcific pancreatitis (non-FCPD) and between the recipients and non-recipients of pancreatic enzyme-replacement-therapy (ERT).

RESULTS

Out of 54 patients with pancreatic diabetes, 35 patients had chronic calcific pancreatitis. They underwent CGM, median HbA1c 9.20 % (77 mmol/mol) and mean Time-In-Range (TIR) being 41.21 % (23.48). Only 5 (15.2 %) patients achieved target TIR>70 % while 16 (48.5 %) patients had high glycemic-variability [Coefficient-of-variation (CV) > 36 %]. Patients with FCPD (n = 14) had higher hypoglycemia-indices like Time-Below-Range (18.92 % vs 8.20 %; p = 0.03) and Low-Blood-Glucose-Index (18.14 % vs 6.04 %; p = 0.02) compared to non-FCPD (n = 21). HbA1c% and hyperglycemic excursions were similar in both groups. Recipients of ERT (n = 20) had lower glycemic-variability [Standard Deviation (SD) 52.15 % vs 68.14 % and CV 32.59 % vs 41.79 %, p < 0.05 for both) than non-recipients. ERT-recipients had no serious hypoglycemia within the 14 days. On subgroup analysis, lower glycemic-variability and hypoglycemia with ERT were seen only in FCPD but not in non-FCPD subgroup (50.13 vs 77.91, 30.09 vs 48.36 for SD and CV respectively, p < 0.05).

CONCLUSION

Patients with type 3c DM due to chronic pancreatitis have high frequency of hyperglycemic and hypoglycemic excursions, with those with FCPD having a particularly higher risk of hypoglycemia and glycemic-variability. Those receiving pancreatic ERT had lesser glycemic variability and hypoglycemia. The small sample size and lack of objective markers of documentation of exocrine pancreatic insufficiency like fecal elastase highlight the need for further larger studies in this field.

Surrogate measures of first-phase insulin secretion versus reference methods intravenous glucose tolerance test and hyperglycemic clamp: a systematic review and meta-analyses

INTRODUCTION

In this systematic review, we investigated the diagnostic accuracy of surrogate measures of insulin secretion based on fasting samples and the oral glucose tolerance test (OGTT). The first phase of insulin secretion was calculated using two gold standard methods; the hyperglycemic clamp (HGC) test and intravenous glucose tolerance test (IVGTT).

RESEARCH DESIGN AND METHODS

We conducted searches in the PubMed, Cochrane Central, and Web of Science databases, the last of which was conducted at the end of June 2021. Studies were included that measured first-phase insulin secretion in adults using both a gold-standard reference method (either HGC or IVGTT) and one or more surrogate measures from either fasting samples, OGTT or a meal-tolerance test. QUADAS-2, a revised tool for the quality assessment of diagnostic accuracy studies, was used for quality assessment. Random-effects meta-analyses were performed to examine the correlation between first-phase measured with gold standard and surrogate methods.

RESULTS

A total of 33 articles, encompassing 5362 individuals with normal glucose tolerance, pre-diabetes or type 2 diabetes, were included in our systematic review. Homeostatic model assessment (HOMA)-beta and Insulinogenic Index 30 (IGI(30)) were the surrogate measures validated in the largest number of studies (17 and 13, respectively). HOMA-beta's pooled correlation to the reference methods was 0.48 (95% CI 0.40 to 0.56) The pooled correlation of IGI to the reference methods was 0.61 (95% CI 0.54 to 0.68). The surrogate measures with the highest correlation to the reference methods were Kadowaki (0.67 (95% CI 0.61 to 0.73)) and Stumvoll's first-phase secretion (0.65 (95% CI 0.58 to 0.71)), both calculated from an OGTT.

CONCLUSIONS

Surrogate measures from the first 30 min of an OGTT capture the first phase of insulin secretion and are a good choice for epidemiological studies. HOMA-beta has a moderate correlation to the reference methods but is not a measure of the first phase specifically.

PROSPERO REGISTRATION NUMBER

The meta-analysis was registered at PROSPERO (Id: CRD42020169064) before inclusion started.

Ultrashort-Peptide-Responsive Gene Switches for Regulation of Therapeutic Protein Expression in Mammalian Cells

Despite the array of mammalian transgene switches available for regulating therapeutic protein expression in response to small molecules or physical stimuli, issues remain, including cytotoxicity of chemical inducers and limited biocompatibility of physical cues. This study introduces gene switches driven by short peptides comprising eight or fewer amino acid residues. Utilizing a competence regulator (ComR) and sigma factor X-inducing peptide (XIP) from Streptococcus vestibularis as the receptor and inducer, respectively, this study develops two strategies for a peptide-activated transgene control system. The first strategy involves fusing ComR with a transactivation domain and utilizes ComR-dependent synthetic promoters to drive expression of the gene-of-interest, activated by XIP, thereby confirming its membrane penetrability and intracellular functionality. The second strategy features an orthogonal synthetic receptor exposing ComR extracellularly (ComREXTRA), greatly increasing sensitivity with exceptional responsiveness to short peptides. In a proof-of-concept study, peptides are administered to type-1 diabetic mice with microencapsulated engineered human cells expressing ComREXTRA for control of insulin expression, restoring normoglycemia. It is envisioned that this system will encourage the development of short peptide drugs and promote the introduction of non-toxic, orthogonal, and highly biocompatible personalized biopharmaceuticals for gene- and cell-based therapies.

Role of Systemic Factors in Improving the Prognosis of Diabetic Retinal Disease and Predicting Response to Diabetic Retinopathy Treatment

Topic

To review clinical evidence on systemic factors that might be relevant to update diabetic retinal disease (DRD) staging systems, including prediction of DRD onset, progression, and response to treatment.

Clinical relevance

Systemic factors may improve new staging systems for DRD to better assess risk of disease worsening and predict response to therapy.

Methods

The Systemic Health Working Group of the Mary Tyler Moore Vision Initiative reviewed systemic factors individually and in multivariate models for prediction of DRD onset or progression (i.e., prognosis) or response to treatments (prediction).

Results

There was consistent evidence for associations of longer diabetes duration, higher glycosylated hemoglobin (HbA1c), and male sex with DRD onset and progression. There is strong trial evidence for the effect of reducing HbA1c and reducing DRD progression. There is strong evidence that higher blood pressure (BP) is a risk factor for DRD incidence and for progression. Pregnancy has been consistently reported to be associated with worsening of DRD but recent studies reflecting modern care standards are lacking. In studies examining multivariate prognostic models of DRD onset, HbA1c and diabetes duration were consistently retained as significant predictors of DRD onset. There was evidence of associations of BP and sex with DRD onset. In multivariate prognostic models examining DRD progression, retinal measures were consistently found to be a significant predictor of DRD with little evidence of any useful marginal increment in prognostic information with the inclusion of systemic risk factor data apart from retinal image data in multivariate models. For predicting the impact of treatment, although there are small studies that quantify prognostic information based on imaging data alone or systemic factors alone, there are currently no large studies that quantify marginal prognostic information within a multivariate model, including both imaging and systemic factors.

Conclusion

With standard imaging techniques and ways of processing images rapidly evolving, an international network of centers is needed to routinely capture systemic health factors simultaneously to retinal images so that gains in prediction increment may be precisely quantified to determine the usefulness of various health factors in the prognosis of DRD and prediction of response to treatment.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Frequency of C-peptide and antibody levels (anti GAD, Islet cell antibodies, insulin auto antibodies) in children of Pakistan with Type-1 diabetes

Background and Objective

The autoimmune mechanism in T1DM causes gradual loss of pancreatic β-cell, which progresses to hyperglycemia and ultimate reliance on consistent insulin therapy. T1DM has been the commonest type of diabetes in children and this study will help in refining indulgent towards the problem and its pathophysiology in our people. The objective was to find out the prevalence of C-peptide and antibody levels (anti GAD, ICA, IAA and IA2) in children and adolescents of Pakistan with T1DM.

Methods

We conducted this cross-sectional study at Department of Pediatric Endocrinology, National Institute of Child Health, Karachi between August 2019 to February 2020 and included 98 children who had T1DM for more than one month. Subjects whose GFR was <30ml/min were omitted from the study. Among those registered subjects, C-peptide, human islet cell antibody (ICA), insulin auto antibodies (IAA) and anti-glutamic acid decarboxylase were assessed. Demographical and laboratorial facts were noted on a pre-constructed proforma.

Results

There were 77(78.3%) cases who had level of C-peptide <0.8 and anti-GAD was found in 47(48%) subjects. 35(35.7%) cases found positive for IA2 .and 7(7.1%) patients had insulin auto antibodies positive while ICA was negative in total 98(100%) subjects.

Conclusion

Children with T1 DM possessed increased levels of anti-GAD antibodies, insulin autoantibodies and anti (IA2) but islet cells antibodies were negligible in our population when checked at a point of time. C-peptide may be normal in some, but its level declines with long duration of diabetes in children.

Correlation between islet α cell function and peripheral neuropathy in patients with type 2 diabetes mellitus

BACKGROUND

This study explored the correlation between pancreatic islet α cell function, as reflected by the plasma glucagon levels, and Diabetic Peripheral Neuropathy (DPN) in patients with Type 2 Diabetes Mellitus (T2DM).

METHODS

A total of 358 patients with T2DM were retrospectively enrolled in this study and divided into the Non-DPN (NDPN) group (n = 220) and the DPN group (n = 138). All patients underwent an oral glucose tolerance test to detect levels of blood glucose, insulin and glucagon, and the Area Under the Curve (AUC) for Glucagon (AUCglu) was used to estimate the overall glucagon level. The Peripheral Nerve Conduction Velocity (PNCV), Amplitude (PNCA) and Latency (PNCL) were obtained with electromyography, and their Z scores were calculated.

RESULTS

There were significant differences regarding the age, disease duration, serum levels of alanine aminotransferase, aspartate aminotransferase, urea nitrogen, high-density lipoprotein, and 2h-C peptide between these two groups (p < 0.05). The NDPN group had higher glucagon levels at 30, 60 and 120 min and AUCglu (p < 0.05). The Z-scores of PNCV and PNCA showed an increasing trend (p < 0.05), while the Z-score of PNCL showed a decreasing trend (p < 0.05). The glucagon levels were positively correlated with PNCV and PNCA, but negatively correlated with PNCL, with Gluca30min having the strongest correlation (p < 0.05). Gluca30min was independently related to PNCV, PNCL, PNCA and DPN, respectively (p < 0.05). The function of pancreatic α islet cells, as reflected by the plasma glucagon level, is closely related to the occurrence of DPN in T2DM patients.

CONCLUSION

Gluca30min may be a potentially valuable independent predictor for the occurrence of DPN.

Interlaboratory Comparison of Antibody-Free LC-MS/MS Measurements of C-peptide and Insulin

BACKGROUND

The enhanced precision and selectivity of liquid chromatography-tandem mass spectrometry (LC-MS/MS) makes it an attractive alternative to certain clinical immunoassays. Easily transferrable work flows could help facilitate harmonization and ensure high-quality patient care. We aimed to evaluate the interlaboratory comparability of antibody-free multiplexed insulin and C-peptide LC-MS/MS measurements.

METHODS

The laboratories that comprise the Targeted Mass Spectrometry Assays for Diabetes and Obesity Research (TaMADOR) consortium verified the performance of a validated peptide-based assay (reproducibility, linearity, and lower limit of the measuring interval [LLMI]). An interlaboratory comparison study was then performed using shared calibrators, de-identified leftover laboratory samples, and reference materials.

RESULTS

During verification, the measurements were precise (2.7% to 3.7%CV), linear (4 to 15 ng/mL for C-peptide and 2 to 14 ng/mL for insulin), and sensitive (LLMI of 0.04 to 0.10 ng/mL for C-peptide and 0.03 ng/mL for insulin). Median imprecision across the 3 laboratories was 13.4% (inter-quartile range [IQR] 11.6%) for C-peptide and 22.2% (IQR 20.9%) for insulin using individual measurements, and 10.8% (IQR 8.7%) and 15.3% (IQR 14.9%) for C-peptide and insulin, respectively, when replicate measurements were averaged. Method comparison with the University of Missouri reference method for C-peptide demonstrated a robust linear correlation with a slope of 1.044 and r2 = 0.99.

CONCLUSIONS

Our results suggest that combined LC-MS/MS measurements of C-peptide and insulin are robust and adaptable and that standardization with a reference measurement procedure could allow accurate and precise measurements across sites, which could be important to diabetes research and help patient care in the future.

Efficacy and safety of visepegenatide, a long-acting weekly GLP-1 receptor agonist as monotherapy in type 2 diabetes mellitus: a randomised, double-blind, parallel, placebo-controlled phase 3 trial

Background

Type 2 diabetes (T2DM) remains a challenge to treat despite the expansion of various therapeutic classes. Visepegenatide (PB-119) is a once a week, subcutaneous, glucagon-like peptide-1 receptor agonist (GLP-1 RA) injection without the requirement of dose titration that has shown glycaemic control and safety profile in two phase 2 studies conducted in China and the United States, respectively. The aim of this study was to evaluate the efficacy and safety of visepegenatide as a monotherapy in treatment-naïve patients with T2DM.

Methods

This was a multicentre, double-blind, parallel, placebo-controlled, phase 3 trial conducted in 30 centres in China. Adult participants (aged 18-75 years) with T2DM, glycated haemoglobin (HbA1c) of 7.5%-11.0% [58.47-96.73 mmol/mol], body mass index (BMI) of 18-40 kg/m2, and who had been treated with diet and exercise alone for at least 8 weeks before the screening visit were eligible for enrolment. After a 4-week placebo injection run-in period, participants with HbA1c of 7.0%-10.5% [53.0-91.3 mmol/mol] and fasting plasma glucose (FPG) < 15 mmol/L were randomised in a ratio of 1:1 to receive visepegenatide (150 μg) or placebo subcutaneous injections once a week for 24 weeks. The treatment was extended to another 28 weeks during which all participants received visepegenatide. The primary outcome was a change in HbA1c from baseline to week 24. This study was registered with ClinicalTrials.gov, as NCT04504370.

Findings

Between November 2, 2020, and November 2, 2022, we randomly assigned 273 adult participants to the visepegenatide (n = 137) and placebo (n = 136) groups. In total, 257 (94.12%) participants, 131 (95.6%) on visepegenatide, and 126 (92.6%) on placebo, completed the double-blinded treatment period. At baseline, the mean (SD) HbA1c was 8.47% (0.81) [69.07 [8.81] mmol/mol], which rapidly decreased to 7.63% (0.80) [59.94 [8.70] mmol/mol] with visepegenatide by week 4 of treatment, and the change from baseline was significantly greater than that in the placebo group (-0.82% [-0.90 to -0.74]; [-8.99 [-9.89 to -8.10] mmol/mol] vs -0.30% [-0.41 to -0.19]; [-3.30 [-4.50 to -2.09] mmol/mol]). At week 24, when evaluating the effects of treatment with treatment policy estimand, the least square mean (LSM change in HbA1c from baseline was -1.36 (95% confidence interval [CI] -1.52 to -1.20) [-14.84 [-16.60 to -13.08] mmol/mol] in the visepegenatide group vs -0.63 (-0.79 to -0.46) [-6.84 [-8.61 to -5.07] mmol/mol] in the placebo group. The reduction in HbA1c was significantly greater with visepegenatide than placebo (LSM difference -0.73, 95% CI -0.96 to -0.50; p < 0.001). When evaluating the treatment estimand with hypothetic policy, the LSM change in HbA1c from baseline in the visepegenatide group (-1.37 [-1.53 to -1.20]) [-14.95 [-16.76 to -13.14] mmol/mol] was significantly greater than the placebo group (-0.63 [-0.81 to -0.45]) [6.90 (-8.89 to -4.90) mmol/mol]. The LSM difference was (-0.74, 95% CI -0.98 to -0.49; [-8.00 [-10.50 to -5.50] mmol/mol]; p < 0.001]. A significantly greater proportion of the visepegenatide group achieved a target HbA1c level of <7% (<53 mmol/mol) than the placebo (50.4% vs 14.2%; p < 0.05) and stringent HbA1c level of ≤6.5% (≤48 mmol/mol) (26.7% vs 7.9%), respectively. There was also a significantly greater improvement in FPG, 2-h postprandial glucose, homeostasis model assessment (HOMA) of beta cell function, post-prandial insulin, fasting, and post-prandial C-peptide level (p < 0.05) with visepegenatide treatment. The number (3 [2.2%]) of participants who received rescue therapy in the visepegenatide group was remarkably lower compared with those (17 [12.5%]) in the placebo group (p < 0.05). During the extended treatment period, visepegenatide consistently maintained the efficacy till week 52 confirmed by all the above endpoints. The reduction in HbA1c at week 52 was -1.39% (-1.58 to -1.19) [-15.14 [-17.28 to -13.01] mmol/mol], which was even greater than that at week 24. There was also a significant improvement in HOMA-insulin resistance (p = 0.004) at week 52 compared with the baseline value. For the placebo→visepegenatide group, which received visepegenatide in the extended treatment period, a notable decrease in HbA1c at week 52 compared to baseline was observed. The change from baseline in HbA1c was -1.49% (-1.68 to -1.30) [-16.27 [-18.37 to -14.16] mmol/mol]. The outcome was in the same direction as the visepegenatide group from the double-blind treatment period. Comprehensive benefits of visepegenatide including weight loss, improvement in lipid profile, and reduction in blood pressure have been demonstrated in this study. Visepegenatide reduced the body weight in a BMI-dependent manner that was prominent in BMI ˃32 kg/m2 with a mean (SD) reduction of -4.77 (13.94) kg at week 52 (p < 0.05). Incidences of gastrointestinal adverse events were less common than other weekly GLP-1 RA in the market, and most of the adverse events were mild and moderate in nature, occurring in the first weeks of the treatment, and were transient. No serious hypoglycaemia or grade 2 hypoglycaemia (blood glucose: ≤3 mmol/L) was reported during the study.

Interpretation

As a monotherapy, visepegenatide provided rapid without the risk of hypoglycaemia, significant, and sustainable glycaemic control by improving islet β-cell function and insulin resistance. Treatment with visepegenatide induced early treatment response in reducing HbA1c and maintaining glycaemic control for 52 weeks. Meanwhile, visepegenatide provided a comprehensive benefit in body weight loss, lipids, and blood pressure reduction. Visepegenatide had a better safety profile than other weekly GLP-1 RA in participants with T2DM even without the requirement of dose titration. Visepegenatide would provide an optimal treatment approach with its high benefit and low-risk balance.

Funding

PegBio Co., Ltd.

Reference Standards for C-Peptide in Korean Population: A Korean Endocrine Hormone Reference Standard Data Center Study

BACKGRUOUND

The Korean Endocrine Hormone Reference Standard Data Center (KEHRS DC) has created reference standards (RSs) for endocrine hormones since 2020. This study is the first of its kind, wherein the KEHRS DC established RSs for serum Cpeptide levels in a healthy Korean population.

METHODS

Healthy Korean adults were recruited from May 2021 to September 2023. After excluding participants according to our criteria, serum samples were collected; each participant could then choose between fasting glucose only or fasting glucose plus an oral glucose tolerance test (OGTT). If their sample showed high glucose (≥100 mg/dL) or hemoglobin A1c (HbA1c) (≥5.70%), their C-peptide levels were excluded from analyzing the RSs.

RESULTS

A total of 1,532 participants were recruited; however, only the data of 1,050 participants were analyzed after excluding those whose samples showed hyperglycemia or high HbA1c. Post-30-minute OGTT data from 342 subjects and post-120-minute OGTT data from 351 subjects were used. The means±2 standard deviations and expanded uncertainties of fasting, post-30-minute and 120-minute OGTT C-peptide levels were 1.26±0.82 and 0.34-3.18, 4.74±3.57 and 1.14-8.33, and 4.85±3.58 and 1.25-8.34 ng/mL, respectively. Serum C-peptide levels correlated with obesity, serum glucose levels, and HbA1c levels.

CONCLUSION

The RSs for serum C-peptide levels established in this study are expected to be useful in both clinical and related fields.

Expert Opinion on Current Trends in the Use of Insulin in the Management of People with Type 2 Diabetes from the South-Eastern European Region and Israel

Despite the availability of various antihyperglycaemic therapies and comprehensive guidelines, glycaemic control in diabetes management has not improved significantly during the last decade in the real-world clinical setting. Treatment inertia arising from a complex interplay among patient-, clinician- and healthcare-system-related factors is the prime reason for this suboptimal glycaemic control. Also, the key factor leading to inadequate glycaemic levels remains limited communication between healthcare professionals (HCPs) and people with type 2 diabetes (PwT2D). Early insulin administration has several advantages including reduced glucotoxicity, high efficacy and preserved β-cell mass/function, leading to lowering the risk of diabetes complications. The current publication is based on consensus of experts from the South-Eastern European region and Israel who reviewed the existing evidence and guidelines for the treatment of PwT2D. Herein, the experts emphasised the timely use of insulin, preferably second-generation basal insulin (BI) analogues and intensification using basal-plus therapy, as the most-potent glucose-lowering treatment choice in the real-world clinical setting. Despite an increase in the use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs), the experts urged timely insulin initiation for inadequate glycaemic control in PwT2D. Furthermore, the combination of BI and GLP-1 RA addressing both fasting plasma glucose and post-prandial excursions as a free- or fixed-ratio combination was identified to reduce treatment complexity and burden. To minimise discontinuation and improve adherence, the experts reiterated quality, regular interactions and discussions between HCPs and PwT2D/carers for their involvement in the diabetes management decision-making process. Clinicians and HCPs should consider the opinions of the experts in accordance with the most recent recommendations for diabetes management.

Impartial feature selection using multi-agent reinforcement learning for adverse glycemic event prediction

We developed an attention model to predict future adverse glycemic events 30 min in advance based on the observation of past glycemic values over a 35 min period. The proposed model effectively encodes insulin administration and meal intake time using Time2Vec (T2V) for glucose prediction. The proposed impartial feature selection algorithm is designed to distribute rewards proportionally according to agent contributions. Agent contributions are calculated by a step-by-step negation of updated agents. Thus, the proposed feature selection algorithm optimizes features from electronic medical records to improve performance. For evaluation, we collected continuous glucose monitoring data from 102 patients with type 2 diabetes admitted to Cheonan Hospital, Soonchunhyang University. Using our proposed model, we achieved F1-scores of 89.0%, 60.6%, and 89.8% for normoglycemia, hypoglycemia, and hyperglycemia, respectively.

Utility of Fasting C-Peptide for the Diagnostic Differentiation of Patients with Type 1, Type 2 Diabetes, MODY, and LADA

BACKGROUND

The prevalence of obesity has increased in patients with type 1 diabetes (T1D) and latent autoimmune diabetes of the adult (LADA), limiting the use of clinical features such as the body mass index for its differentiation with type 2 diabetes (T2D). Additionally, some patients with maturity-onset diabetes of the young (MODY) or LADA are misdiagnosed as having T2D. The evaluation of autoantibodies and genetic testing are not fully available. We aimed to evaluate the utility of a widely available and less expensive diagnostic tool such as C-peptide to differentiate between T1D, T2D, MODY, and LADA.

METHODS

Our study included 38 patients with T1D, 49 with T2D, 13 with MODY, and 61 with LADA. We recorded anthropometric measurements, biochemical profiles, and antidiabetic treatment and determined C-peptide, anti-GAD65, and anti-IA2 antibodies.

RESULTS

C-peptide concentration differed significantly among populations (T1D: 0.2 ng/mL; T2D: 2.4 ng/mL; MODY: 1.14 ng/mL; LADA: 1.87 ng/mL). Through a ROC curve, we observed that the C-peptide cut-off point of 0.95 ng/mL allows differentiation between T1D and T2D (sensitivity 82%, specificity 77%); 0.82 ng/mL between T1D and LADA (sensitivity 82%, specificity 77%); and 1.65 ng/mL between T2D and MODY (sensitivity 72%, specificity 72%).

CONCLUSIONS

C-peptide is useful for the diagnostic differentiation of patients with type 1, type 2 diabetes, MODY, and LADA.

Functional Analysis of a Novel HNF4A Variant Identified in a Patient With MODY1

Context

HNF4A-maturity-onset diabetes of the young (MODY1) is a relatively rare subtype of monogenic diabetes caused by loss of function of the HNF4A gene, which encodes the transcription factor HNF4α. HNF4α is known to form heterodimers, and the various combinations of isoforms that make up these heterodimers have been reported to result in a diversity of targeted genes. However, the function of individual HNF4α variant isoforms and the heterodimers comprising both wild-type (WT) and variant HNF4α have not yet been assessed.

Objective

In this study, we analyzed the functional consequence of the HNF4A D248Y variant in vitro.

Methods

We investigated the case of a 12-year-old Japanese girl who developed diabetes at age 11 years. Genetic sequencing detected a novel heterozygous missense HNF4A variant (c.742G > T, p.Asp248Tyr; referred as "D248Y") in the patient and her relatives who presented with diabetes.

Results

Although the WT HNF4α isoforms (HNF4α2, HNF4α3, HNF4α8, HNF4α9) enhanced the INS gene promoter activity in HepG2 cells, the promoter activity of D248Y was consistently low across all isoforms. The presence of D248Y in homodimers and heterodimers, comprising either HNF4α8 or HNF4α3 or a combination of both isoforms, also reduced the INS promoter activity in Panc-1 cells.

Conclusion

We report the clinical course of a patient with HNF4A-MODY and the functional analysis of novel HNF4A variants, with a focus on the isoforms and heterodimers they form. Our results serve to improve the understanding of the dominant-negative effects of pathogenic HNF4A variants.

Novel thiazolidin-4-one benzenesulfonamide hybrids as PPARγ agonists: Design, synthesis and in vivo anti-diabetic evaluation

In the current study, two series of novel thiazolidin-4-one benzenesulfonamide arylidene hybrids 9a-l and 10a-f were designed, synthesized and tested in vitro for their PPARɣ agonistic activity. The phenethyl thiazolidin-4-one sulphonamide 9l showed the highest PPARɣ activation % by 41.7%. Whereas, the 3-methoxy- and 4-methyl-4-benzyloxy thiazolidin-4-one sulphonamides 9i, and 9k revealed moderate PPARɣ activation % of 31.7, and 32.8%, respectively, in addition, the 3-methoxy-3-benzyloxy thiazolidin-4-one sulphonamide 10d showed PPARɣ activation % of 33.7% compared to pioglitazone. Compounds 9b, 9i, 9k, 9l, and 10d revealed higher selectivity to PPARɣ over the PPARδ, and PPARα isoforms. An immunohistochemical study was performed in HepG-2 cells to confirm the PPARɣ protein expression for the most active compounds. Compounds 9i, 9k, and 10d showed higher PPARɣ expression than that of pioglitazone. Pharmacological studies were also performed to determine the anti-diabetic activity in rats at a dose of 36 mg/kg, and it was revealed that compounds 9i and 10d improved insulin secretion as well as anti-diabetic effects. The 3-methoxy-4-benzyloxy thiazolidin-4-one sulphonamide 9i showed a better anti-diabetic activity than pioglitazone. Moreover, it showed a rise in blood insulin by 4-folds and C-peptide levels by 48.8%, as well as improved insulin sensitivity. Moreover, compound 9i improved diabetic complications as evidenced by decreasing liver serum enzymes, restoration of total protein and kidney functions. Besides, it combated oxidative stress status and exerted anti-hyperlipidemic effect. Compound 9i showed a superior activity by normalizing some parameters and amelioration of pancreatic, hepatic, and renal histopathological alterations caused by STZ-induction of diabetes. Molecular docking studies, molecular dynamic simulations, and protein ligand interaction analysis were also performed for the newly synthesized compounds to investigate their predicted binding pattern and energies in PPARɣ binding site.

Computational peptide discovery with a genetic programming approach

The development of peptides for therapeutic targets or biomarkers for disease diagnosis is a challenging task in protein engineering. Current approaches are tedious, often time-consuming and require complex laboratory data due to the vast search spaces that need to be considered. In silico methods can accelerate research and substantially reduce costs. Evolutionary algorithms are a promising approach for exploring large search spaces and can facilitate the discovery of new peptides. This study presents the development and use of a new variant of the genetic-programming-based POET algorithm, called POETRegex , where individuals are represented by a list of regular expressions. This algorithm was trained on a small curated dataset and employed to generate new peptides improving the sensitivity of peptides in magnetic resonance imaging with chemical exchange saturation transfer (CEST). The resulting model achieves a performance gain of 20% over the initial POET models and is able to predict a candidate peptide with a 58% performance increase compared to the gold-standard peptide. By combining the power of genetic programming with the flexibility of regular expressions, new peptide targets were identified that improve the sensitivity of detection by CEST. This approach provides a promising research direction for the efficient identification of peptides with therapeutic or diagnostic potential.

Future clinical prospects of C-peptide testing in the early diagnosis of gestational diabetes

Gestational diabetes is typically diagnosed in the late second or third trimester of pregnancy. It is one of the most common metabolic disorders among expectant mothers, with potential serious short- and long-term complications for both maternal and offspring health. C-peptide is secreted from pancreatic beta-cells into circulation in equimolar amounts with insulin. It is a useful biomarker to estimate the beta-cell function because it undergoes negligible hepatic clearance and consequently it has a longer half-life compared to insulin. Pregnancy induces increased insulin resistance due to physiological changes in hormonal and metabolic homeostasis. Inadequate compensation by islet beta-cells results in hyperglycemia. The standard oral glucose tolerance test at 24-28 wk of gestation sets the diagnosis. Accumulated evidence from prospective studies indicates a link between early pregnancy C-peptide levels and the risk of subsequent gestational diabetes. Elevated C-peptide levels and surrogate glycemic indices at the beginning of pregnancy could prompt appropriate strategies for secondary prevention.

Fasted C-Peptide Distribution and Associated Clinical Factors in Adults With Longstanding Type 1 Diabetes: Analysis of the Canadian Study of Longevity in Type 1 Diabetes

OBJECTIVE

Although insulin production is reportedly retained in many people with longstanding type 1 diabetes (T1D), the magnitude and relevance of connecting peptide (C-peptide) production are uncertain. In this study, we aimed to define fasted C-peptide distributions and associated clinical factors.

METHODS

In a cross-sectional analysis of the Canadian Study of Longevity, fasted serum and urinary C-peptide was measured in 74 patients with longstanding T1D (duration ≥50 years) and 75 age- and sex-matched controls. Extensive phenotyping for complications was performed and patient-reported variables were included. C-peptide distributions were analyzed, and multivariable logistic regression was used to assess the variable association in participants with T1D.

RESULTS

The 74 participants with T1D had a mean age of 66±8 years, a disease duration of 54 (interquartile range 52 to 58) years, and a glycated hemoglobin (A1C) of 7.4%±0.8% (56.8±9.15 mmol/mol). The 75 controls had a mean age of 65±8 years and an A1C of 5.7%±0.4% (38.4±4.05 mmol/mol). Participants with T1D had lower fasted serum C-peptide than controls (0.013±0.022 vs 1.595±1.099 nmol/L, p<0.001). Of the participants with T1D, C-peptide was detectable in 30 of 73 (41%) serum samples, 32 of 74 (43%) urine samples, and 48 of 74 (65%) for either serum or urine. The variables independently associated with detectable serum or urinary C-peptide were lower total daily insulin requirement (odds ratio 2.351 [for 1 lower unit/kg], p=0.013) and lower hypoglycemia worry score (odds ratio 1.059 [for 1 point lower on the worry subscore of the Hypoglycemia Fear Survey], p=0.030).

CONCLUSIONS

Although detectable C-peptide in longstanding diabetes was common, the magnitude of concentration was extremely low when compared with age- and sex-matched controls. Despite minimal detectability, its presence is validated by lower insulin requirements and strongly associated with lower hypoglycemia worry.

C-peptide Level in Patients With Uncontrolled Type 2 Diabetes Mellitus on Oral Anti-diabetic Drugs

BACKGROUND

In the development and progression of type 2 diabetes mellitus, β-cell dysfunction occurs after insulin resistance. Despite poor glycaemic control, there is a practice of increasing the dose of oral anti-diabetics or adding more drugs to the regimen due to the common perception that low endogenous insulin secretion is related to type 1 diabetes mellitus only and patient's poor compliance to injectables. Keeping this perspective in mind, this study was conducted to assess the prevalence of beta cell dysfunction by low serum C-peptide levels and its correlation with poor glycaemic control.

MATERIALS AND METHODS

A total of 134 patients with type 2 diabetes mellitus for more than 10 years on oral anti-diabetic drugs fulfilling our eligibility criteria were enrolled in our study. Blood samples for fasting blood sugar and fasting C-peptide level were taken before breakfast and uptake of anti-diabetic drugs. Correlation analysis was performed to evaluate the relationship between fasting C-peptide and glycaemic control with respect to glycated haemoglobin (HbA1c).

RESULTS

Of the patients, 19.40% had insufficient beta cell reserve serum levels (C-peptide < 0.5 ng/ml), of which most of the patients (14/26 = 53.85%) had poor glycaemic control (HbA1c < 8.0%). Overall, there was a significant correlation between poor glycaemic control with respect to HbA1c and low serum C-peptide levels (p < 0.05). We found a significant association of beta cell dysfunction (low fasting C-peptide level) with the use of insulin secretagogue. The proportion of patients with C-peptide levels less than 0.5 ng/ml was lower in patients using sodium-glucose cotransporter-2 (SGLT-2) inhibitors as compared to insulin secretagogue.

CONCLUSION

SGLT-2 inhibitors should be preferred over other anti-diabetic drugs as an add-on to existing metformin therapy. Insulin requirement must be assessed in patients who have long-term type 2 diabetes mellitus.

Glycated haemoglobin, HOMA2-B, C-peptide to glucose ratio and type 2 diabetes clusters as predictors for therapy failure in individuals with type 2 diabetes without insulin therapy: A registry analysis

AIM

Some people with type 2 diabetes mellitus (T2D) and declining β-cell function do require insulin over time. Various laboratory parameters, indices of glucose metabolism or phenotypes of T2D (clusters) have been suggested, which might predict future therapy failure (TF), indicating the need for insulin therapy initiation. This analysis evaluated glycated haemoglobin (HbA1c), homeostatic model assessment (HOMA)2-B, C-peptide to glucose ratio (CGR) and diabetes clusters as predictive parameters for the occurrence of glycaemic TF in individuals diagnosed with T2D without previous insulin therapy.

MATERIALS AND METHODS

In total, 159 individuals with T2D [41% female, median age 50 (IQR: 53-69) years, diabetes duration 9 (5-15) years], without insulin therapy were prospectively evaluated for the occurrence of a composite primary endpoint, including HbA1c increasing or remaining >8.0% (64 mmol/mol) 3 months after baseline on non-insulin glucose-lowering agents, insulin initiation or hospital admissions because of acute hyperglycaemic events. Diabetes clusters were formed according to previously described characteristics. Only severe autoimmune diabetes clusters were excluded because of a small amount of glutamate decarboxylase antibody-positive participants. The other clusters were distributed as mild age-related diabetes 33%; severe insulin-deficient diabetes 31%; mild obesity-related diabetes 20%; and severe insulin-resistant diabetes 15%.

RESULTS

During a median observation of 57 months, higher tertiles of HbA1c at baseline, HOMA2-B, as well as a lower CGR were significantly predictive for the occurrence of the primary endpoint. The probability of meeting the primary endpoint was the highest for mild obesity-related diabetes [hazard ratio 3.28 (95% confidence interval 1.75-6.2)], followed by severe insulin-deficient diabetes [hazard ratio 2.03 (95% confidence interval 1.1-3.7)], mild age-related diabetes and the lowest for severe insulin-resistant diabetes. The best performance to predict TF with an area under the curve (AUC) of 0.77 was HbA1c at baseline, followed by HOMA2-B (AUC 0.69) and CGR (AUC 0.64).

CONCLUSION

HbA1c, indices of insulin secretion capacity (HOMA2-B and CGR) and T2D clusters might be applicable tools to guide practitioners in the decision of whether insulin is required in people already diagnosed with T2D. These findings need to be validated in prospective studies.

Approaches to Measuring Beta Cell Reserve and Defining Partial Clinical Remission in Paediatric Type 1 Diabetes

CONTEXT

Type 1 diabetes (T1D) results from the autoimmune T-cell mediated destruction of pancreatic beta cells leading to insufficient insulin secretion. At the time of diagnosis of T1D, there is residual beta cell function that declines over the subsequent months to years. Recent interventions have been approved to preserve beta cell function in evolving T1D.

OBJECTIVE

The aim of this review is to summarise the approaches used to assess residual beta cell function in evolving T1D, and to highlight potential future directions.

METHODS

Studies including subjects aged 0 to 18 years were included in this review. The following search terms were used; "(type 1 diabetes) and (partial remission)" and "(type 1 diabetes) and (honeymoon)". References of included studies were reviewed to determine if additional relevant studies were eligible.

RESULTS

There are numerous approaches to quantifying beta cell reserve in evolving T1D. These include c-peptide measurement after a mixed meal or glucagon stimuli, fasting c-peptide, the urinary c-peptide/creatinine ratio, insulin dose-adjusted haemoglobin A1c, and other clinical models to estimate beta cell function. Other biomarkers may have a role, including the proinsulin/c-peptide ratio, cytokines, and microRNA. Studies using thresholds to determine if residual beta cell function is present often differ in values used to define remission.

CONCLUSIONS

As interventions are approved to preserve beta cell function, it will become increasingly necessary to quantify residual beta cell function in research and clinical contexts. In this report, we have highlighted the strengths and limitations of the current approaches.

A Placebo-Controlled, Double-Blind Clinical Investigation to Evaluate the Efficacy of a Patented Trigonella foenum-graecum Seed Extract "Fenfuro®" in Type 2 Diabetics

BACKGROUND

Trigonella foenum-graecum (Fenugreek) is an extensively researched phytotherapeutic for the management of Type 2 diabetes without any associated side effects. The major anti-diabetic bioactive constituents present in the plant are furostanolic saponins, which are more abundantly available in the seed of the plant. However, the bioavailability of these components depends on the method of extraction and hence formulation of the phytotherapeutic constitutes a critical step for its success.

OBJECTIVE

The present study reports the efficacy of a novel, patented fenugreek seed extract, Fenfuro®, containing significant amount of furostanolic saponins, in an open-labelled, two-armed, single centric study on a group of 204 patients with Type 2 diabetes mellitus over a period of twelve consecutive weeks.

RESULTS

Administration of Fenfuro® in the dosage of 500 mg twice daily along with metformin and/or sulfonylurea-based prescribed antidiabetic drug resulted in a reduction of post-prandial glucose by more than 33% along with significant reduction in fasting glucose, both of which were greater than what resulted for the patient group receiving only Metformin and/or Sulfonylurea therapy. Fenfuro® also resulted in reduction in mean baseline HOMA index from 4.27 to 3.765, indicating restoration of insulin sensitivity which was also supported by a significant decrease in serum insulin levels by >10% as well as slight reduction in the levels of C-peptide. However, in the case of the Metformin and/or Sulfonylurea group, insulin levels were found to increase by more than 14%, which clearly indicated that drug-induced suppression of glucose levels instead of restoration of glucose homeostasis. Administration of the formulation was also found to be free from any adverse side effects as there were no changes in hematological profile, liver function and renal function.

CONCLUSION

The study demonstrated the promising potential of this novel phytotherapeutic, Fenfuro®, in long-term holistic management of type-2 diabetes.

High-Fat Diets in Animal Models of Alzheimer's Disease: How Can Eating Too Much Fat Increase Alzheimer's Disease Risk?

High dietary intake of saturated fatty acids is a suspected risk factor for neurodegenerative diseases, including Alzheimer's disease (AD). To decipher the causal link behind these associations, high-fat diets (HFD) have been repeatedly investigated in animal models. Preclinical studies allow full control over dietary composition, avoiding ethical concerns in clinical trials. The goal of the present article is to provide a narrative review of reports on HFD in animal models of AD. Eligibility criteria included mouse models of AD fed a HFD defined as > 35% of fat/weight and western diets containing > 1% cholesterol or > 15% sugar. MEDLINE and Embase databases were searched from 1946 to August 2022, and 32 preclinical studies were included in the review. HFD-induced obesity and metabolic disturbances such as insulin resistance and glucose intolerance have been replicated in most studies, but with methodological variability. Most studies have found an aggravating effect of HFD on brain Aβ pathology, whereas tau pathology has been much less studied, and results are more equivocal. While most reports show HFD-induced impairment on cognitive behavior, confounding factors may blur their interpretation. In summary, despite conflicting results, exposing rodents to diets highly enriched in saturated fat induces not only metabolic defects, but also cognitive impairment often accompanied by aggravated neuropathological markers, most notably Aβ burden. Although there are important variations between methods, particularly the lack of diet characterization, these studies collectively suggest that excessive intake of saturated fat should be avoided in order to lower the incidence of AD.

Less common forms of diabetes in young population

Types diabetes other than type 1 are generally considered rare in children and adolescents. The incidence of type 2 diabetes has increased dramatically over the past decade in some ethnic groups. The increased incidence of this type of diabetes mellitus has corresponded tem-porally to unprecedented increases in body weight and obesity prevalence in adolescents in various ethnic populations. Early treatment of insulin resistance is important to prevent the development of diabetes. In therapy, lifestyle modification is essential for weight loss, and if this is not enough, pharmacotherapy is required. Maturity-onset diabetes of the young (MODY), another type of insulin-dependent diabetes, is characterised by early onset and autosomal dominant inheritance. MODY is mainly caused by β-cell defects, resulting in insufficient insulin secretion for a given blood glucose level. Unlike non-insulin-dependent diabetes in youth (NIDDM-Y), there is no significant increase in insulin resistance. The purpose of this article is to characterise and present types of diabetes other than type 1 found in the young population.

Identification of eight genomic protective alleles for mitochondrial diabetes by Kinship-graph convolutional network

AIMS

Nearly 85% of maternally inherited diabetes and deafness (MIDD) are caused by the m.3243A>G mutation in the mitochondrial DNA. However, the clinical phenotypes of MIDD may also be influenced by the nuclear genome, this study aimed to investigate nuclear genome variants that influence clinical phenotypes associated with m.3243A>G mutation in MIDD based on whole-genome sequencing of the patients belonging to pedigrees.

MATERIALS AND METHODS

We analyzed a whole-genome sequencing (WGS) dataset from blood samples of 38 MIDD patients with the m.3243A > G mutation belonging to 10 pedigrees, by developing a Kinship-graph convolutional network approach, called Ki-GCN, integrated with the conventional genome-wide association study (GWAS) methods.

RESULTS

We identified eight protective alleles in the nuclear genome that have protective effects against the onset of MIDD, related deafness, and also type 2 diabetes. Based on these eight protective alleles, we constructed an effective logistic regression model to predict the early or late onset of MIDD patients.

CONCLUSIONS

There are protective alleles in the nuclear genome that are associated with the onset-age of MIDD patients and might also provide protective effects on the deafness derived from MIDD patients.

Unveiling Diabetes: Categories, Genetics, Diagnostics, Treatments, and Future Horizons

Diabetes mellitus is a global epidemic affecting millions of individuals worldwide. This comprehensive review aims to provide a thorough understanding of the categorization, disease identity, genetic architecture, diagnosis, and treatment of diabetes. The categorization of diabetes is discussed, with a focus on type 1 and type 2 diabetes, as well as the lesser-known types, type 3 and type 4 diabetes. The geographical variation, age, gender, and ethnic differences in the prevalence of type 1 and type 2 diabetes are explored. The impact of disease identity on disease management and the role of autoimmunity in diabetes are examined. The genetic architecture of diabetes, including the interplay between genotype and phenotype, is discussed to enhance our understanding of the underlying mechanisms. The importance of insulin injection sites and the insulin signalling pathway in diabetes management are highlighted. The diagnostic techniques for diabetes are reviewed, along with advancements for improved differentiation between types. Treatment and management approaches, including medications used in diabetes management are presented. Finally, future perspectives are discussed, emphasizing the need for further research and interventions to address the global burden of diabetes. This review serves as a valuable resource for healthcare professionals, researchers, and policymakers, providing insights to develop targeted strategies for the prevention, diagnosis, and management of this complex disease.

Type 2 Diabetes Mellitus in a Young Female Later Diagnosed as​​​​ Pancreatogenic Diabetes: The Dilemma in Classifying Diabetes Mellitus

Diabetes mellitus type 3c (DM3c) is a diabetes caused by pancreatic pathology. It occurs due to the destruction of the endocrine islet cells. Diabetes diagnosed at the age of 20-30 years share a common dilemma in segregating between the type of diabetes the patient has, as its management varies depending on the type of diabetes the patient is harboring. However, insulin remains the treatment of choice in later decades as the pancreatic reserves of beta cells exhaust, although it takes decades to happen. We report a case of a woman who was diagnosed with diabetes mellitus at the age of 26, was on oral hypoglycemic agents (OHA), and was shifted to insulin therapy as she became non-responsive to OHA in a short span of six years, which was alarming. The patient presented to us with the chief complaints of recurrent abdominal pain that aggravated on taking meals and was associated with multiple episodes of vomiting for two months. Blood gas analysis on admission had no evidence of metabolic acidosis, urine ketones were negative, and a random blood sugar test (RBS:202) excluded the possibility of diabetic ketoacidosis. Serum amylase and serum lipase were within normal limits. Contrast-enhanced computed tomography (CECT) of the abdomen was suggestive of the atrophic pancreas with the non-dilated main pancreatic duct. Magnetic resonance cholangiopancreatography (MRCP) was done to rule out the congenital anomalies of the pancreas responsible for chronic pancreatitis, which showed no structural abnormalities. During our clinical workup, we postulated that the diabetes she was diagnosed with at the age of 26 was DM3c, i.e., pancreatogenic diabetes. The rapid shift of patients from OHA to subcutaneous insulin in a short span must be alarming to the physician managing diabetes and needs extensive workup to look upon the etiology of the same.

Exploring aryl hydrocarbon receptor (AhR) as a target for Bisphenol-A (BPA)-induced pancreatic islet toxicity and impaired glucose homeostasis: Protective efficacy of ethanol extract of Centella asiatica

The estrogenic impact of Bisphenol-A (BPA), a widely recognized endocrine disruptor, causes disruption of pancreatic β-cell function through estrogen receptors (ERs). While BPA's binding affinity for ERs is significantly lower than that of its natural counterpart, estrogen, recent observations of BPA's affinity for aryl hydrocarbon receptor (AhR) in specific cellular contexts have sparked a specific question: does AhR play a role in BPA's toxicological effects within the endocrine pancreas? To explore this question, we investigated BPA's (10 and 100 μg/ kg body weight/day for 21 days) potential to activate AhR within pancreatic islets and assessed the protective role of ethanol extract of Centella asiatica (CA) (200 and 400 mg/kg body weight/day for 21 days) against BPA-mediated toxicity in mouse model. Our results indicate that BPA effectively triggers the activation of AhR and modulates its target genes within pancreatic islets. In contrast, CA activates AhR but directs downstream pathways differentially and activates Nrf2. Additionally, CA was observed to counteract the disruption caused by BPA in glucose homeostasis and insulin sensitivity. Furthermore, BPA-induced oxidative stress and exaggerated production of proinflammatory cytokines were effectively counteracted by CA supplementation. In summary, our study suggests that CA influenced AhR signaling to mitigate the disrupted pancreatic endocrine function in BPA exposed mice. By shedding light on how BPA interacts with AhR, our research provides valuable insights into the mechanisms involved in the diabetogenic actions of BPA.

Oral glucose sensing in cephalic phase insulin release

Oral stimulation with foods or food components elicits cephalic phase insulin release (CPIR), which limits postprandial hyperglycemia. Despite its physiological importance, the specific gustatory mechanisms that elicit CPIR have not been clearly defined. While most studies point to glucose and glucose-containing saccharides (e.g., sucrose, maltodextrins) as being the most consistent elicitors, it is not apparent whether this is due to the detection of glucose per se, or to the perceived taste cues associated with these stimuli (e.g., sweetness, starchiness). This study investigated potential sensory mechanisms involved with eliciting CPIR in humans, focusing on the role of oral glucose detection and associated taste. Four stimulus conditions possessing different carbohydrate and taste profiles were designed: 1) glucose alone; 2) glucose mixed with lactisole, a sweet taste inhibitor; 3) maltodextrin, which is digested to starchy- and sweet-tasting products during oral processing; and 4) maltodextrin mixed with lactisole and acarbose, an oral digestion inhibitor. Healthy adults (N = 22) attended four sessions where blood samples were drawn before and after oral stimulation with one of the target stimuli. Plasma c-peptide, insulin, and glucose concentrations were then analyzed. Whereas glucose alone elicited CPIR (one-sample t-test, p < 0.05), it did not stimulate the response in the presence of lactisole. Likewise, maltodextrin alone stimulated CPIR (p < 0.05), but maltodextrin with lactisole and acarbose did not. Together, these findings indicate that glucose is an effective CPIR stimulus, but that an associated taste sensation also serves as an important cue for triggering this response in humans.

Comparison of customized vacuum sealing drainage and vacuum sealing drainage in the treatment of diabetic foot ulcers: a retrospective analysis

BACKGROUND

The prevalence of diabetic foot ulcers, a common, more serious chronic diabetes-related complication, is increasing. Vacuum sealing drainage (VSD) constitutes an effective adjunctive treatment for diabetic foot ulcers. Factors, such as poor glycemic control, ischemia, and infection prolong wound healing time, and VSD products are expensive and unaffordable for many patients.

OBJECTIVE

To compare the use of customized VSD and customized VSD in the treatment of diabetic foot ulcer.

METHOD

This retrospective study included 83 patients with diabetic foot ulcers in customized VSD (n = 44) and VSD (n = 39) groups. Baseline data, efficacy after 14 days, total treatment efficiency, final outcome (28 days after treatment, healing rate), average treatment cost, and hospitalization (days) of the two groups were compared. Factors affecting wound healing were analyzed.

RESULTS

No significant intergroup differences in the baseline data were detected (VSD vs. customized VAD, p > 0.05). Treatment efficacy was higher in the customized VSD group than in the VSD group after 14 days (p < 0.05), although total treatment efficiency in both groups reached 100%. The final outcome in the customized VSD group was better (vs. VSD group, p < 0.05), and the wound healing rate was higher than in the VSD group (66.7% vs. 33.3%). The mean treatment cost and hospital days were greater in the VSD group (vs. customized VSD group; p < 0.05). Factors affecting wound healing include age, Wagner classification, HDL-C, and fasting C-peptide. Younger age, low Wagner classification grade, low HDL-C level, and high fasting C-peptide contribute to higher healing rate, CONCLUSION: Efficacy and final outcome of customized VSD were better than that of VSD; the customized VSD device is simple and convenient to operate, and enables cost-effective treatment.

Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus

BACKGROUND

Numerous laboratory tests are used in the diagnosis and management of diabetes mellitus. The quality of the scientific evidence supporting the use of these assays varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for laboratory analysis in screening, diagnosis, or monitoring of diabetes. The overall quality of the evidence and the strength of the recommendations were evaluated. The draft consensus recommendations were evaluated by invited reviewers and presented for public comment. Suggestions were incorporated as deemed appropriate by the authors (see Acknowledgments). The guidelines were reviewed by the Evidence Based Laboratory Medicine Committee and the Board of Directors of the American Association for Clinical Chemistry and by the Professional Practice Committee of the American Diabetes Association.

CONTENT

Diabetes can be diagnosed by demonstrating increased concentrations of glucose in venous plasma or increased hemoglobin A1c (HbA1c) in the blood. Glycemic control is monitored by the people with diabetes measuring their own blood glucose with meters and/or with continuous interstitial glucose monitoring (CGM) devices and also by laboratory analysis of HbA1c. The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of ketones, autoantibodies, urine albumin, insulin, proinsulin, and C-peptide are addressed.

SUMMARY

The guidelines provide specific recommendations based on published data or derived from expert consensus. Several analytes are found to have minimal clinical value at the present time, and measurement of them is not recommended.

PAX4 loss of function increases diabetes risk by altering human pancreatic endocrine cell development

The coding variant (p.Arg192His) in the transcription factor PAX4 is associated with an altered risk for type 2 diabetes (T2D) in East Asian populations. In mice, Pax4 is essential for beta cell formation but its role on human beta cell development and/or function is unknown. Participants carrying the PAX4 p.His192 allele exhibited decreased pancreatic beta cell function compared to homozygotes for the p.192Arg allele in a cross-sectional study in which we carried out an intravenous glucose tolerance test and an oral glucose tolerance test. In a pedigree of a patient with young onset diabetes, several members carry a newly identified p.Tyr186X allele. In the human beta cell model, EndoC-βH1, PAX4 knockdown led to impaired insulin secretion, reduced total insulin content, and altered hormone gene expression. Deletion of PAX4 in human induced pluripotent stem cell (hiPSC)-derived islet-like cells resulted in derepression of alpha cell gene expression. In vitro differentiation of hiPSCs carrying PAX4 p.His192 and p.X186 risk alleles exhibited increased polyhormonal endocrine cell formation and reduced insulin content that can be reversed with gene correction. Together, we demonstrate the role of PAX4 in human endocrine cell development, beta cell function, and its contribution to T2D-risk.

Loss of ATP-sensitive channel expression and function decreases opioid sensitivity in a mouse model of type 2 diabetes

During diabetes, β-cell dysfunction due to loss of potassium channels sensitive to ATP, known as KATP channels occurs progressively over time contributing to hyperglycemia. KATP channels are additionally present in the central and peripheral nervous systems and are downstream targets of opioid receptor signaling. The aim of this study is to investigate if KATP channel expression or activity in the nervous system changes in diabetic mice and if morphine antinociception changes in mice fed a high fat diet (HFD) for 16 weeks compared to controls. Mechanical thresholds were also monitored before and after administration of glyburide or nateglinide, KATP channel antagonists, for four weeks. HFD mice have decreased antinociception to systemic morphine, which is exacerbated after systemic treatment with glyburide or nateglinide. HFD mice also have lower rotarod scores, decreased mobility in an open field test, and lower burrowing behavior compared to their control diet counterparts, which is unaffected by KATP channel antagonist delivery. Expression of KATP channel subunits, Kcnj11 (Kir6.2) and Abcc8 (SUR1), were decreased in the peripheral and central nervous system in HFD mice, which is significantly correlated with baseline paw withdrawal thresholds. Upregulation of SUR1 through an adenovirus delivered intrathecally increased morphine antinociception in HFD mice, whereas Kir6.2 upregulation improved morphine antinociception only marginally. Perspective: This article presents the potential link between KATP channel function and neuropathy during diabetes. There is a need for increased knowledge in how diabetes affects structural and molecular changes in the nervous system to lead to the progression of chronic pain and sensory issues.

A retrospective comparison between intensive and nonintensive insulin regimens in type 2 diabetes mellitus

BACKGROUND

This study compared the outcomes between intensive and nonintensive insulin regimens and assessed the predictive factors for failing to achieve the glycated hemoglobin (A1C) goals in type-2-diabetes-mellitus (T2DM) patients requiring insulin therapy.

METHODS

A single-center, retrospective assessment of the medical records of 125 T2DM patients undergoing intensive (46 patients) and nonintensive insulin therapy (79 patients) were conducted.

RESULTS

No significant differences were found when the intensive and nonintensive insulin therapy groups were compared in terms of the percentage decreases of glucose and A1C levels. The mean A1C levels of the nonintensive and intensive groups declined from 11.15% and 11.30% to 7.97% and 8.06%, respectively.

CONCLUSIONS

Both intensive and nonintensive insulin therapies improved the baseline glycemic parameters but being overweight or obese and/or being reluctant to dietary recommendations led to treatment failures regardless of the insulin regimen.

Computational Peptide Discovery with a Genetic Programming Approach

Background

The development of peptides for therapeutic targets or biomarkers for disease diagnosis is a challenging task in protein engineering. Current approaches are tedious, often time-consuming and require complex laboratory data due to the vast search space. In silico methods can accelerate research and substantially reduce costs. Evolutionary algorithms are a promising approach for exploring large search spaces and facilitating the discovery of new peptides.

Results

This study presents the development and use of a variant of the initial POET algorithm, called P O E T R e g e x , which is based on genetic programming, where individuals are represented by a list of regular expressions. The program was trained on a small curated dataset and employed to predict new peptides that can improve the problem of sensitivity in detecting peptides through magnetic resonance imaging using chemical exchange saturation transfer (CEST). The resulting model achieves a performance gain of 20% over the initial POET variant and is able to predict a candidate peptide with a 58% performance increase compared to the gold-standard peptide.

Conclusions

By combining the power of genetic programming with the flexibility of regular expressions, new potential peptide targets were identified to improve the sensitivity of detection by CEST. This approach provides a promising research direction for the efficient identification of peptides with therapeutic or diagnostic potential.

Optimized LC-MS/MS Method for the Detection of ppCCK(21-44): A Surrogate to Monitor Human Cholecystokinin Secretion

The hormone cholecystokinin (CCK) is secreted postprandially from duodenal enteroendocrine cells and circulates in the low picomolar range. Detection of this digestion and appetite-regulating hormone currently relies on the use of immunoassays, many of which suffer from insufficient sensitivity in the physiological range and cross-reactivity problems with gastrin, which circulates at higher plasma concentrations. As an alternative to existing techniques, a liquid chromatography and mass spectrometry-based method was developed to measure CCK-derived peptides in cell culture supernatants. The method was initially applied to organoid studies and was capable of detecting both CCK8 and an N-terminal peptide fragment (prepro) ppCCK(21-44) in supernatants following stimulation. Extraction optimization was performed using statistical modeling software, enabling a quantitative LC-MS/MS method for ppCCK(21-44) capable of detecting this peptide in the low pM range in human plasma and secretion buffer solutions. Plasma samples from healthy individuals receiving a standardized meal (Ensure) after an overnight fast were analyzed; however, the method only had sensitivity to detect ppCCK(21-44). Secretion studies employing human intestinal organoids and meal studies in healthy volunteers confirmed that ppCCK(21-44) is a suitable surrogate analyte for measuring the release of CCK in vitro and in vivo.

Intrapancreatic autologous stem cell therapy for type 1 diabetes - an experimental study

Introduction

Type 1 diabetes, also known as juvenile diabetes or insulin-dependent diabetes, is a chronic autoimmune condition in which the pancreas makes little or no insulin leading to resultant hyperglycemia. The incidence of type 1 diabetes in India is 0.26 per 1000 children.

Materials and methods

The author treated 25 patients with type 1 diabetes with autologous intrapancreatic stem cell therapy in the last 5 years. A group of 26 patients of type 1 diabetes with conventional treatment of insulin injections was put as a control group in the same period.

Results

The results of the therapy group were substantially superior to the control group, which came statistically highly significant. The variable compared were weight gain, the daily requirement of insulin and its drop after therapy, the rise of C-peptide levels and drop in anti-glutamic acid decarboxylase antibody, drop in HbA1c levels, and drop in fasting and postprandial blood sugar.

Discussion

When stem cells are given intravenously, the majority are engulfed by the lungs and only a small fraction is delivered to the pancreas. When injected into the pancreas, through its arterial blood supply, due to the larger size and irregular shape of stem cells, they are retained in tissue spaces and do not escape from the venous side, thus achieving far higher concentration in the pancreas compared to the intravenous route.

Conclusions

Intrapancreatic stem cell therapy for type 1 diabetes is safe, affordable, and effective. It has the potential to become a viable treatment option for type 1 diabetes patients.

Exploration of suitable external quality assessment materials for serum C-peptide measurement

OBJECTIVES

To find suitable external quality assessment (EQA) materials for serum C-peptide, we evaluated the commutability of five types of processed materials.

METHODS

Seventy-four individual serum samples and 12 processed samples including three EQA samples currently in use, frozen human serum pools (FHSP), and three other kinds of processed samples were prepared by dissolving WHO International Standard Reagent for C-peptide (WHO ISR 13/146) in three different matrixes: 0.05 % bovine serum albumin, fetal bovine serum and human serum pools. Samples were analyzed using the isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) method and six widely used immunoassays. The commutabilities of processed materials were assessed according to the difference in bias approach recommended by the IFCC. And the short- and long-term stability of FHSP samples at different temperatures were also evaluated.

RESULTS

Out of the five kinds of processed materials, FHSP samples were commutable on most assays. In contrast, the EQA materials currently in use were only commutable on a few immunoassays. Additionally, processed materials derived from WHO ISR 13/146 were found to be un-commutable on over half of immunoassays. The FHSP samples could be stably stored at 4 and -20 °C for at least 16 days, and at -80 °C for at least 1 year, but at room temperature only for 12 h.

CONCLUSIONS

With clarified commutability and stability information, the human serum pool samples along with the developed ID-LC-MS/MS method could be used in the EQA program to promote the comparability among laboratories for C-peptide measurement in China.

Normative range of various serum hormonal parameters among Indian women of reproductive age: ICMR-PCOS task force study outcome

Background

The hormonal profile varies considerably with age, gender, ethnicity, diet or physiological state of an individual. Limited population-specific studies have studied the variations in hormonal parameters among apparently healthy women. We aimed to analyse the biological reference interval for various hormonal parameters in the reproductive-aged healthy Indian women.

Methods

Out of 3877 participants that were clinically evaluated, 1441 subjects were subjected to laboratory investigations. All participants underwent a detailed clinical, biochemical and hormonal profiling. The hormone analysis was carried out at a single centre using a uniform methodology. Among the participants evaluated for biochemical and hormonal parameters, subjects that presented any abnormal profile or had incomplete investigations (n = 593) were excluded for further analysis.

Findings

The mean age (±SD) of the subjects retained in the final analysis (n = 848) was 29.9 (±6.3) years. In the present study, the biological reference interval (2.5th-97.5th centile) observed were: serum T4: μg/dL (5.23-12.31), TSH: μg/mL (0.52-4.16) and serum prolactin: ng/mL (5.13-37.35), LH: mIU/mL (2.75-20.68), FSH: mIU/mL 2.59-15.12), serum total testosterone: ng/mL (0.06-0.68), fasting insulin: mIU/mL (1.92-39.72), morning cortisol: μg/dL (4.71-19.64), DHEAS:μg/dL (50.61-342.6) and SHBG: nmol/L (21.37-117.54). Unlike T4, TSH, LH, and E2, the biological reference interval for prolactin, FSH, testosterone, C-peptide insulin and DHEAS varied when the subjects were stratified by age (p < 0.05). The comparative analysis showed marginal differences in the normative ranges for the hormones analysed among different populations.

Interpretation

Our first large composite data on hormonal measures will benefit future endeavours to define biological reference intervals in reproductive-aged Indian women.

Funding

The study was financially supported by the grant-in-aid from ICMR vide file No:5/7/13337/2015-RBMH.

Predictors of T2DM Remission after Bariatric Surgery in Patients with a BMI < 35 kg/m2: a Meta-Analysis

PURPOSE

Although a few studies have reported the predictors of postoperative diabetes remission in patients with body mass index (BMI) < 35 kg/m2, the conclusions are still inconsistent. This meta-analysis aimed to evaluate the preoperative clinical factors of type 2 diabetes mellitus (T2DM) remission after bariatric surgery.

MATERIALS AND METHODS

The PubMed, Embase, and Cochrane Library databases were systematically searched until April 2022. The Newcastle-Ottawa Scale was used for quality assessment. Statistical heterogeneity was assessed with the I2 statistic, followed by subgroup and sensitivity analyses.

RESULTS

16 studies involving 932 patients were selected. T2DM remission was negatively correlated with age, duration, insulin use, fasting plasma glucose, fasting insulin, and glycosylated hemoglobin levels. While BMI, body weight, waist circumference, and C-peptide levels were positive predictors of T2DM remission in patients with a BMI < 35 kg/m2. However, there was no significant association between gender, oral hypoglycemic agent, homeostasis model assessment, high-density lipoprotein, low-density lipoprotein, total cholesterol, triglycerides, systolic blood pressure, diastolic blood pressure, and remission rate.

CONCLUSION

Patients with younger age, short diabetes duration, more obesity, better glucose control, and better β cell function were more likely to achieve T2DM remission in patients with a BMI < 35 kg/m2 after bariatric surgery.

Effect of a 12-Week Polyphenol Rutin Intervention on Markers of Pancreatic β-Cell Function and Gut Microbiota in Adults with Overweight without Diabetes

Supplementation with prebiotic polyphenol rutin is a potential dietary therapy for type 2 diabetes prevention in adults with obesity, based on previous glycaemic improvement in transgenic mouse models. Gut microbiota are hypothesised to underpin these effects. We investigated the effect of rutin supplementation on pancreatic β-cell function measured as C-peptide/glucose ratio, and 16S rRNA gene-based gut microbiota profiles, in a cohort of individuals with overweight plus normoglycaemia or prediabetes. Eighty-seven participants were enrolled, aged 18-65 years with BMI of 23-35 kg/m2. This was a 12-week double-blind randomised controlled trial (RCT), with 3 treatments comprising (i) placebo control, (ii) 500 mg/day encapsulated rutin, and (iii) 500 mg/day rutin-supplemented yoghurt. A 2-h oral glucose tolerance test (OGTT) was performed at baseline and at the end of the trial, with faecal samples also collected. Compliance with treatment was high (~90%), but rutin in both capsule and dietary format did not alter pancreatic β-cell response to OGTT over 12 weeks. Gut bacterial community composition also did not significantly change, with Firmicutes dominating irrespective of treatment. Fasting plasma glucose negatively correlated with the abundance of the butyrate producer Roseburia inulinivorans, known for its anti-inflammatory capacity. This is the first RCT to investigate postprandial pancreatic β-cell function in response to rutin supplementation.

Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus

BACKGROUND

Numerous laboratory tests are used in the diagnosis and management of diabetes mellitus. The quality of the scientific evidence supporting the use of these assays varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for laboratory analysis in screening, diagnosis, or monitoring of diabetes. The overall quality of the evidence and the strength of the recommendations were evaluated. The draft consensus recommendations were evaluated by invited reviewers and presented for public comment. Suggestions were incorporated as deemed appropriate by the authors (see Acknowledgments). The guidelines were reviewed by the Evidence Based Laboratory Medicine Committee and the Board of Directors of the American Association of Clinical Chemistry and by the Professional Practice Committee of the American Diabetes Association.

CONTENT

Diabetes can be diagnosed by demonstrating increased concentrations of glucose in venous plasma or increased hemoglobin A1c (Hb A1c) in the blood. Glycemic control is monitored by the people with diabetes measuring their own blood glucose with meters and/or with continuous interstitial glucose monitoring (CGM) devices and also by laboratory analysis of Hb A1c. The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of ketones, autoantibodies, urine albumin, insulin, proinsulin, and C-peptide are addressed.

SUMMARY

The guidelines provide specific recommendations based on published data or derived from expert consensus. Several analytes are found to have minimal clinical value at the present time, and measurement of them is not recommended.

A Cross-sectional Study to Assess Beta-Cell Function in Individuals with Recently Diagnosed Young-Onset Type 2 Diabetes Mellitus and Its' Complications

Objective

The primary objective was to assess beta-cell function of recently-diagnosed young-onset type 2 diabetes mellitus (T2DM) individuals using basal and stimulated C-peptide levels. The secondary objective was to examine the association between C-peptide with metabolic factors and diabetes complications.

Methodology

A cross-sectional study was conducted for young-onset T2DM individuals aged 18-35 years with a disease duration of not more than 5 years. Plasma C-peptide was measured before and after intravenous glucagon injection. Demographic data, medical history and complications were obtained from medical records and clinical assessment. Continuous data were expressed as median and interquartile range (IQR). Categorical variables were described as frequency or percentage. Multivariable linear regression analysis was used to determine factors associated with C-peptide levels.

Results

113 participants with young-onset T2DM with a median (IQR) age of 29.0 (9.5) years and 24 (36) months were included in this study. The median (IQR) basal and stimulated C-peptide was 619 (655) pmol/L and 1231 (1024) pmol/L. Adequate beta-cell function was present in 78-86% of the participants based on the basal and stimulated C-peptide levels. We found hypertension, obesity and diabetic kidney disease (DKD) to be independently associated with higher C-peptide levels. In contrast, females, smokers, those on insulin therapy and with longer duration of disease had lower C-peptide levels.

Conclusion

Most recently diagnosed young-onset T2DM have adequate beta-cell function. Elevated C-peptide levels associated with obesity, hypertension and diabetic kidney disease suggest insulin resistance as the key driving factor for complications.

An Accurate Isotope Dilution Liquid Chromatography-Tandem Mass Spectrometry Method for Serum C-Peptide and Its Use in Harmonization in China

Background

Serum C-peptide results from various routine methods used in China are highly variable, warranting well-performing methods to serve as an accuracy base to improve the harmonization of C-peptide measurements in China. We developed an accurate isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) method for serum C-peptide measurement and explored its use in harmonization.

Methods

After protein precipitation with Z_nSO₄ solution, C-peptide was extracted from serum samples by anion-exchange solid-phase extraction and quantified by ID-LC-MS/MS in positive ion mode. The precision and analytical recovery of the ID-LC-MS/MS method were assessed. Seventy-six serum samples were analyzed using the ID-LC-MS/MS method and six routine immunoassays. Ordinary linear regression (OLR) and Bland-Altman (BA) analyses were conducted to evaluate the relationship between the ID-LC-MS/MS method and routine immunoassays. Five serum pool samples assigned using the ID-LC-MS/MS method were used to recalibrate the routine assays. OLR and BA analyses were re-conducted after recalibration.

Results

The within-run, between-run, and total precision for the ID-LC-MS/MS method at four concentrations were 1.0%-2.1%, 0.6%-1.2%, and 1.3%-2.2%, respectively. The analytical recoveries for the ID-LC-MS/MS method at three concentrations were 100.3%-100.7%, 100.4%-101.0%, and 99.6%-100.7%. The developed method and the immunoassays were strongly correlated, with all R² >0.98. The comparability among the immunoassays was substantially improved after recalibration.

Conclusions

The performance of the ID-LC-MS/MS method was carefully validated, and this method can be used to improve the harmonization of serum C-peptide measurements in China.

Metabolic Syndrome Screening and Nutritional Status of Patients with Psoriasis: A Scoping Review

Background: Patients with plaque psoriasis have an increased risk of metabolic syndrome. However, no studies have assessed the nutritional status or screening methods of this population. Aims: This review aimed to identify and summarise metabolic syndrome screening criteria and the tools/methods used in nutrition assessment in patients with plaque psoriasis. Data synthesis: PubMed, Web of Science, Ovid and Scopus were searched from inception to March 2023, following the Arkensey and O'Malley framework, to identify articles that report nutritional assessment methods/tools and metabolic screening criteria. Twenty-one studies were identified. Overall, these studies used four different screening criteria to define metabolic syndrome. Patients with psoriasis had a high prevalence of metabolic syndrome and had a poor nutritional status compared to controls. However, only anthropometric measures such as weight, height and waist circumference were employed to determine the nutritional status. Only two studies assessed the vitamin D status. Conclusions: Patients with psoriasis have a poor nutritional status, and they are at risk of nutrient deficiencies. However, these health aspects are not routinely assessed and may increase the risk of malnutrition among these patients. Therefore, additional assessments, such as body composition and dietary assessment, are needed to determine the nutritional status to provide a suitable intervention.

Association of C-peptide level with bone mineral density in type 2 diabetes mellitus

This study revealed that there was no significant linear relationship between fasting C-peptide (FCP) level and bone mineral density (BMD) or fracture risk in type 2 diabetes mellitus (T2DM) patients. However, in the FCP ≤ 1.14 ng/ml group, FCP is positively correlated with whole body (WB), lumbar spine (LS), and femoral neck (FN) BMD and negatively correlated with fracture risk.

PURPOSE

To explore the relationship between C-peptide and BMD and fracture risk in T2DM patients.

METHODS

530 T2DM patients were enrolled and divided into three groups by FCP tertiles, and the clinical data were collected. BMD was measured by dual-energy X-ray absorptiometry (DXA). The 10-year probability of major osteoporotic fractures (MOFs) and hip fractures (HFs) was evaluated by adjusted fracture risk assessment tool (FRAX).

RESULTS

In the FCP ≤ 1.14 ng/ml group, FCP level was positively correlated with WB, LS, and FN BMD, while FCP was negatively correlated with fracture risk and osteoporotic fracture history. However, FCP was not correlated with BMD and fracture risk and osteoporotic fracture history in the 1.14 < FCP ≤ 1.73 ng/ml and FCP > 1.73 ng/ml groups. The study has shown that FCP was an independent factor influencing BMD and fracture risk in the FCP ≤ 1.14 ng/ml group.

CONCLUSIONS

There is no significant linear relationship between FCP level and BMD or fracture risk in T2DM patients. In the FCP ≤ 1.14 ng/ml group, FCP is positively correlated with WB, LS, and FN BMD and negatively correlated with fracture risk, and FCP is an independent influencing factor of BMD and fracture risk. The findings suggest that FCP may predict the risk of osteoporosis or fracture in some T2DM patients, which has a certain clinical value.

The influence of 17β-estradiol plus norethisterone acetate treatment on markers of glucose and insulin metabolism in women: a systematic review and meta-analysis of randomized controlled trials

Objective

Despite the fact that some evidence suggests that the administration of 17β-estradiol plus norethisterone acetate influences glucose and insulin metabolism in women, these findings are still contradictory. Thus, we aimed to examine the impact of the co-administration of 17β-estradiol and norethisterone acetate on glycated haemoglobin (HbA1c), fasting glucose, insulin and C-peptide concentrations in females by means of a systematic review and meta-analysis of randomized controlled trials (RCTs).

Methods

We searched four databases (PubMed/MEDLINE, Scopus, Embase, and Web of Science) using specific keywords and word combinations. The random-effects model (DerSimonian and Laird model) was employed to compute the weighted mean difference (WMD) and 95% confidence intervals (CIs) for the variations from baseline of HbA1c, fasting glucose, insulin, and C-peptide concentrations.

Results

In total, 14 RCTs were entered into the quantitative synthesis. The combined administration of 17β-estradiol and norethisterone acetate decreased HbA1c (WMD: -0.65%, 95% CI: -1.15 to -0.15; P=0.011), fasting glucose (WMD: -11.05 mg/dL, 95% CI: -16.6 to -5.5; P<0.001) and insulin (WMD: -1.35 mIU/L, 95% CI: -2.20 to -0.50; P=0.001) levels. C-peptide concentrations' declined only in females diagnosed with overweight/obesity or diabetes.

Conclusion

Evidence to date points out that the administration of 17β-estradiol and norethisterone acetate has a positive impact on glucose metabolism in women by reducing fasting glucose, HbA1c, and insulin values. Future studies need to confirm the potential benefits of this drug combination in the prevention and/or management of cardiometabolic disorders.

Bariatric surgery in a patient with cystic fibrosis and diabetes: A case report

Cystic fibrosis (CF) is incurable and chronic, causing severe multisystemic damage and long-term complications. The most prominent extrapulmonary long-term complication is CF-related diabetes, which is the most reported form of diabetes in individuals with cystic fibrosis. Here we present the first case of an individual with cystic fibrosis who developed type 2 diabetes due to obesity rather than CF-related diabetes. The type 2 diabetes went into remission due to extreme weight loss after gastric bypass surgery. To our knowledge, this case is also the first report describing the effect of bariatric surgery in a patient with CF. This case demonstrates that patients with CF may present with type 2 diabetes instead of CF-related diabetes. Differential diagnosis of these two types of diabetes is essential for optimal treatment and quality of life.