Clinical expert consensus on the assessment and protection of pancreatic islet β-cell function in type 2 diabetes mellitus

Clinical research progress on β-cell dysfunction in T2DM development in the Chinese population

The prevalence of type-2 diabetes mellitus (T2DM) has increased over 10-fold in the past 40 years in China, which now has the largest T2DM population in the world. Insulin resistance and β-cell dysfunction are the typical features of T2DM. Although both factors play a role, decreased β-cell function and β-cell mass are the predominant factors for progression to T2DM. Considering the differences between Chinese T2DM patients and those of other ethnicities, it is important to characterize β-cell dysfunction in Chinese patients during T2DM progression. Herein, we reviewed the studies on the relationships between β-cell function and T2DM progression in the Chinese population and discussed the differences among individuals of varying ethnicities. Meanwhile, we summarized the risk factors and current treatments of T2DM in Chinese individuals and discussed their impacts on β-cell function with the hope of identifying a better T2DM therapy.

Arterial Spin Labeling (ASL) MRI in Evaluating Pancreatic Blood Perfusion in Subjects With Different Glucose Tolerances

BACKGROUND

The pancreas plays a central role in type 2 diabetes mellitus (T2DM), and its blood flow is usually associated with insulin release demand.

PURPOSE

To noninvasively assess pancreatic blood flow (PBF) changes and modulation in people with different glucose tolerance following a glucose challenge using ASL MRI.

STUDY TYPE

Prospective.

SUBJECTS

Fourteen prediabetes, 22 T2DM, and 40 normal.

FIELD STRENGTH/SEQUENCE

Pseudo-continuous ASL with a turbo gradient spin echo sequence at 3.0 T.

ASSESSMENT

All normal and subjects (diagnosed by oral glucose tolerance test) underwent ASL after fasting for at least 6 hours. The normal and prediabetes groups additionally had ASL scans at 5, 10, 15, 20, and 25 minutes following oral glucose (50 mL, 5%). PBF maps were generated from the ASL data and measured at body and tail. The ability of baseline PBF (BL-PBF) of body, tail (BL-PBFtail), and their average to determine abnormal glucose tolerance and stage was assessed.

STATISTICAL TESTS

ANOVA, Mann-Whitney U test, Kruskal-Wallis H test, paired sample t-test, intra-class correlation coefficient, repeated measures ANOVA, correlation analysis, receiver operating characteristic analysis, and logistic regression analysis. A P value <0.05 was considered significant.

RESULTS

There were significant differences in BL-PBF among the three groups. The prediabetes group exhibited significantly lower PBF than the normal group at all time points; Both groups showed similar changing trends in PBF (peaking at the 15th minute and subsequently declining). The BL-PBFtail had the highest diagnostic performance when evaluating abnormal glucose tolerance or stage (area under the curves = 0.800, 0.584, respectively) and was an independent risk factor for glucose tolerance status.

DATA CONCLUSION

ASL can noninvasively assess changes in PBF among individuals with varying glucose tolerance and in response to glucose challenge, which could be linked to insulin release demand and might help characterize changes in pancreatic endocrine function.

EVIDENCE LEVEL

2 TECHNICAL EFFICACY: Stage 1.

Optimized Spatial Transformer for Segmenting Pancreas Abnormalities

The precise delineation of the pancreas from clinical images poses a substantial obstacle in the realm of medical image analysis and surgical procedures. Challenges arise from the complexities of clinical image analysis and complications in clinical practice related to the pancreas. To tackle these challenges, a novel approach called the Spatial Horned Lizard Attention Approach (SHLAM) has been developed. As a result, a preprocessing function has been developed to examine and eliminate noise barriers from the trained MRI data. Furthermore, an assessment of the current attributes is conducted, followed by the identification of essential elements for forecasting the impacted region. Once the affected region has been identified, the images undergo segmentation. Furthermore, it is crucial to emphasize that the present study assigns 80% of the data for training and 20% for testing purposes. The optimal parameters were assessed based on precision, accuracy, recall, F-measure, error rate, Dice, and Jaccard. The performance improvement has been demonstrated by validating the method on various existing models. The SHLAM method proposed demonstrated an accuracy rate of 99.6%, surpassing that of all alternative methods.

Levels of anti-insulin antibodies in diabetic retinopathy patients: an observational cross-sectional study

Aim: This study evaluated the levels of anti-insulin antibodies (AIAs) and the influence of some antidiabetic medications on AIA in diabetes mellitus (DM) patients with retinopathy. Patient & methods: An observational cross-sectional study. Results: A lower titer of AIA IgG was observed in the diabetic retinopathy (DR) and DM-only study categories compared with the control group [DR = 86 (5-560), DM-only = 50 (5-500), versus control = 200 (7-565); p = 0.017]. Taking nifedipine and metformin were negatively correlated (r = -0.32, p = 0.04) with the levels of AIA IgE in the DR group. Conclusion: A decreased titer of circulating AIAs was observed in the DR study category, suggesting that AIA may not contribute to the pathogenesis of DR.

Factors that determine glucose variability, defined by the coefficient of variation in continuous glucose monitoring values, in a Chinese population with type 2 diabetes

AIMS

To elucidate the clinical determinants of the coefficient of variation (CV) of glucose by analysing the pancreatic β-cell function of subjects with type 2 diabetes mellitus (T2DM).

METHODS

A total of 716 Chinese subjects with T2DM were included. Continuous glucose monitoring (CGM) was used to assess blood glucose, and the CV was calculated. C-peptide concentration at 0, 0.5, 1, 2 and 3 hours (Cp0h, Cp0.5h, Cp1h, Cp2h and Cp3h, respectively) was measured after a standard 100-g steamed bun meal test to assess pancreatic β-cell function. The determinants of glucose variability defined by the CV of CGM values were explored from two perspectives: the CV of qualitative variables and the CV of quantitative variables.

RESULTS

Our data revealed that C-peptide concentration (Cp0h, Cp0.5h, Cp1h, Cp2h, Cp3h), area under the curve for C-peptide concentration at 0.5 and 3 hours (AUC-Cp0.5h and AUC-Cp3h) decreased with increasing CV quartile (P < 0.05). The CV was negatively correlated with homeostatic model assessment of β-cell function index, C-peptide concentration at all timepoints, and AUC-Cp0.5h and AUC-Cp3h (P < 0.001). Quantile regression analysis showed that AUC-Cp0.5h had an overall negative effect on the CV in the 0.05 to 0.95 quartiles, and AUC-Cp3h tended to have a negative effect on the CV in the 0.2 to 0.65 quartiles. After adjusting for confounders, multinomial logistic regression showed that each 1-unit increase in AUC-Cp0.5h was associated with a 31.7% reduction in the risk of unstable glucose homeostasis (CV > 36%; P = 0.036; odds ratio 0.683; 95% confidence interval 0.478-0.976). We also identified the AUC-Cp0.5h (0.735 ng/mL) and AUC-Cp3h (13.355 ng/mL) cut-off values for predicting unstable glucose homeostasis (CV >36%) in T2DM subjects.

CONCLUSION

Our study suggests that impaired pancreatic β-cell function may be a clinical determining factor of CV of glucose in people with T2DM.

Impact of Preparative Isolation of C-Glycosylflavones Derived from Dianthus superbus on In Vitro Glucose Metabolism

Dianthus superbus L. has been extensively studied for its potential medicinal properties in traditional Chinese medicine and is often consumed as a tea by traditional folk. It has the potential to be exploited in the treatment of inflammation, immunological disorders, and diabetic nephropathy. Based on previous studies, this study continued the separation of another subfraction of Dianthus superbus and established reversed-phase/reversed-phase and reversed-phase/hydrophilic (RPLC) two-dimensional (2D) high-performance liquid chromatography (HPLC) modes, quickly separating two C-glycosylflavones, among which 2″-O-rhamnosyllutonarin was a new compound and isomer with 6‴-O-rhamnosyllutonarin. This is the first study to investigate the effects of 2″-O-rhamnosyllutonarin and 6‴-O-rhamnosyllutonarin on cellular glucose metabolism in vitro. First, molecular docking was used to examine the effects of 2″-O-rhamnosyllutonarin and 6″-O-rhamnosyllutonarin on AKT and AMPK; these two compounds exhibited relatively high activity. Following this, based on the HepG2 cell model of insulin resistance, it was proved that both of the 2″-O-rhamnosyllutonarin and 6‴-O-rhamnosyllutonarin demonstrated substantial efficacy in ameliorating insulin resistance and were found to be non-toxic. Simultaneously, it is expected that the methods developed in this study will provide a basis for future studies concerning the separation and pharmacological effects of C-glycosyl flavonoids.

Role of LncRNA MIAT in Diabetic Complications

Long non-coding RNA (LncRNA) refers to a large class of RNAs with over 200 nucleotides that do not have the function of encoding proteins. In recent years, more and more literature has revealed that lncRNA is involved in manipulating genes related to human health and disease, playing outstanding biological functions, which has attracted widespread attention from researchers. The newly discovered long-stranded non-coding RNA myocardial infarction-related transcript (LncRNA MIAT) is abnormally expressed in a variety of diseases, especially in diabetic complications, and has been proven to have a wide range of effects. This review article aimed to summarize the importance of LncRNA MIAT in diabetic complications, such as diabetic cardiomyopathy, diabetic nephropathy, and diabetic retinopathy, and highlight the latest findings on the pathway and mechanism of its participation in regulating diabetic complications, which may aid in finding new intervention targets for the treatment of diabetic complications. LncRNA MIAT competitively binds microRNAs to regulate gene expression as competitive endogenous RNAs. Thus, this review article has reviewed the biological function and pathogenesis of LncRNA MIAT in diabetic complications and described its role in diabetic complications. This paper will help in finding new therapeutic targets and intervention strategies for diabetes complications.

Spore Oil-Functionalized Selenium Nanoparticles Protect Pancreatic Beta Cells from Palmitic Acid-Induced Apoptosis via Inhibition of Oxidative Stress-Mediated Apoptotic Pathways

Oxidative stress damage of pancreatic β-cells is a key link in the pathogenesis of type 2 diabetes mellitus. A long-term increase of free fatty acids induces the increase of reactive oxygen species (ROS) in β-cells, leading to apoptosis and dysfunction of β-cells. Ganoderma lucidum spore oil (GLSO) is a functional food complex with strong antioxidant activity, but its solubility and stability are poor. In the present study, GLSO-functionalized selenium nanoparticles (GLSO@SeNPs) with high stability and uniform particle size were synthesized by a high-pressure homogeneous emulsification method. The aim of this study was to investigate the protective effects of GLSO@SeNPs on INS-1E rat insulinoma β-cells against palmitic-acid (PA)-induced cell death, as well as the underlying mechanisms. Our results showed that GLSO@SeNPs had good stability and biocompatibility, and they significantly inhibited the PA-induced apoptosis of INS-1E pancreatic cells by regulating the activity of related antioxidant enzymes, including thioredoxin reductase (TrxR), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px). Western blot analysis showed that GLSO@SeNPs reversed the PA-induced changes in MAPK pathway protein expression levels. Thus, the present findings provided a new theoretical basis for utilizing GLSO@SeNPs as a treatment for type 2 diabetes.