Pathogenesis of type 2 diabetes mellitus

Parboiled Rice and Glycemic Control: Effects on Postprandial Glucose, Insulin Sensitivity, and Incretin Response in Healthy and Type 2 Diabetic Individuals, a Pilot Study

Type 2 diabetes mellitus (T2DM) represents a significant global health burden, especially in populations where rice constitutes a dietary staple. Parboiled rice (PBR), known for its lower glycemic index compared to conventional white rice (WR), may offer benefits in managing postprandial hyperglycemia. Nevertheless, the impact of PBR consumption on insulin sensitivity, β-cell function, and incretin hormone responses remains poorly understood.

METHODS

This randomized crossover pilot study aimed to assess and compare the acute effects of PBR and WR intake on postprandial glucose regulation, insulin sensitivity, β-cell functionality, and glucagon-like peptide-1 (GLP-1) responses in healthy subjects and individuals with T2DM. A total of 20 participants were recruited and evenly allocated into healthy (n = 10) and T2DM (n = 10) groups. Following the ingestion of either PBR or WR, blood samples were collected at fasting and various postprandial intervals to determine glucose, insulin, and GLP-1 levels. Insulin sensitivity and β-cell function were evaluated using HOMA-IR, Matsuda Index (MI), and Disposition Index (DI).

RESULTS

As expected, T2DM participants exhibited significantly elevated fasting glucose and insulin levels compared to healthy controls. Consumption of PBR led to significantly lower postprandial glucose responses in healthy subjects relative to WR. Although a similar trend of reduced glucose levels was observed in T2DM subjects after PBR intake, this reduction did not reach statistical significance. Parallel trends were observed in insulin secretion patterns. Moreover, GLP-1 responses were notably diminished in T2DM individuals compared to healthy participants. Importantly, MI and DI values significantly increased after PBR consumption in healthy individuals compared to those with T2DM, indicating improved insulin sensitivity and β-cell responsiveness.

CONCLUSIONS

These preliminary findings suggest that PBR consumption may confer beneficial effects by lowering postprandial glucose and enhancing insulin sensitivity. Further studies with larger cohorts are warranted to confirm these outcomes and elucidate the physiological mechanisms behind PBR's potential role in dietary management strategies for T2DM.

Corticosteroid Use in Musculoskeletal and Neuraxial Interventions: Effects on Glycemic Control

Effective multidisciplinary pain management involves an in-depth knowledge not only of diagnosis and treatment but of how interventional procedures affect patients across all health domains. One of the most common pharmacological tools utilized in patients suffering from chronic pain disorders is corticosteroids. Corticosteroids are leveraged for their anti-inflammatory properties across a wide range of disorders. This review examines the role of corticosteroids and pain management with a specific focus on their metabolic impact regarding glucose metabolism. Corticosteroids have been shown to increase gluconeogenesis, resulting in reduced insulin sensitivity and an impaired peripheral glucose uptake. These varied responses to corticosteroids are especially concerning given the high prevalence of diabetes mellitus in chronic pain patients. There is well-documented evidence of not only transient hyperglycemia but emerging literature on prolonged glycemic disturbances that may have a greater effect on patients than previously recognized. A review of the available literature reveals variations in hyperglycemia depending on corticosteroid type, dose, and various patient-specific factors. Some research does suggest that lower corticosteroid dosages can provide similar therapeutic benefits and potentially reduce glycemic aberrations. Given the current evidence, clinicians should closely monitor patients' hemoglobin A1C levels when determining the risks and benefits of an interventional procedure and consider alternative pain management strategies when appropriate. Future research should focus on optimizing corticosteroid selection and dosing to balance the safety, particularly in diabetic or prediabetic patient populations.

Validating the antidiabetic potential of Nakima (Tupistra clarkei Hook.f.), a traditional food from eastern Himalayan region, through network pharmacology and in vivo experimentation

OBJECTIVE

To explore and understand the antidiabetic activity of Tupistra clarkei Hook.f. inflorescence, providing a scientific explanation to the ethnomedicinal properties.

METHODS

The constituents of the plant were determined through GC-MS analysis, which were used for target prediction and network pharmacology to understand how the plant regulates hyperglycaemia and other diabetes complications. These properties were validated in vivo along with further assessment of the antioxidant potential of the plant, both in vitro and in vivo.

KEY FINDINGS

The plant showed good phenol-flavonoid content, and antioxidant potential both in vitro and in vivo. GC-MS analysis identified 24 constituents of the plant. In silico analysis showed their ability to target 166 proteins that are associated with pathways in controlling hyperglycaemia and other diabetic consequences, protection of pancreatic tissue, insulin secretion, and insulin resistance. This was reflected in the in vivo experiment where T. clarkei showed ability to reduce FBG, LDL-C, VLDL-C levels, improve the levels of HDL-C, and also facilitate reversal of damage in pancreatic islets.

CONCLUSION

Our study validated the antidiabetic potential Tupistra clarkei inflorescence in the in silico and in vivo assessment, and has proved to have good antioxidant activity and potential against diabetes. However, further clinical trials are essential.

Constitutively active glucagon receptor drives high blood glucose in birds

The maintenance of blood glucose, the body's primary source of energy, is indispensable for overall health and metabolic homeostasis. It is regulated predominantly by the glucagon receptor family which is highly conserved in vertebrates1-4. Compared with other vertebrates, avian blood glucose levels are relatively high5,6, and blood glucose regulatory mechanisms in birds have remained unclear. Here we show that high hepatic expression of the avian glucagon receptor (GCGR) in association with constitutively active Gs signalling is dependent on the interaction of different domains. In vivo experiments showed that expression of constitutively active GCGR in hepatic cells led to correspondingly high blood glucose, rapid hepatic lipid utilization and high metabolic rates via downstream signalling pathway activation in fish, reptiles, birds and mammals. Furthermore, we identified a point mutation proximal to the GCGR gene region in chicken that resulted in reduced GCGR mRNA expression and increased body weight. Overexpressing a natural human GCGR variant (HsGCGR(H339R)) with modest constitutive activity in mice demonstrated that high expression of this variant increased blood glucose concentration and reduced body weight. In sum, we find that high expression and constitutive activity of GCGR may have contributed to the evolution of flight in the ancestors of birds.

Association of serum cortisol with insulin secretion and plasma aldosterone with insulin resistance in untreated type 2 diabetes: a cross-sectional study

BACKGROUND

Insulin secretion and resistance are key pathophysiological factors in type 2 diabetes. However, only 55% of patients achieve long-term blood glucose treatment goals, highlighting the need to clarify the pathophysiology of type 2 diabetes. While cortisol and aldosterone levels have been linked to insulin secretion and resistance in participants without type 2 diabetes, their role in patients with type 2 diabetes remains unclear. In this study, we aimed to investigate the relationships among insulin secretion, insulin resistance, and cortisol or aldosterone levels in patients with untreated type 2 diabetes.

METHODS

We retrospectively reviewed 121 patients with untreated type 2 diabetes mellitus. We analyzed the relationships between various clinical parameters, including adrenal hormones, and insulin secretion (homeostatic model assessment [HOMA2-%B]) or insulin resistance (HOMA2-IR). Multiple regression analysis was performed to identify parameters associated with HOMA2-%B or HOMA2-IR.

RESULTS

Spearman's rank correlation coefficient revealed that body weight (BW); body mass index (BMI); estimated glomerular filtration rate; and serum creatinine, uric acid, total cholesterol, high-density lipoprotein cholesterol (HDL-C), sodium, potassium, chloride, fasting blood glucose (FBG), glycated hemoglobin (HbA1c), serum C-peptide, and cortisol levels were significantly correlated with HOMA2-%B. Similarly, BW, BMI, aspartate transaminase levels, alanine transaminase (ALT) levels, triglyceride levels, HDL-C levels, FBG levels, serum C-peptide levels, renin activity, and plasma aldosterone concentration (PAC) were significantly correlated with HOMA2-IR. Multiple regression analysis revealed BMI, HbA1c levels, and cortisol levels as predictors of HOMA2-%B, whereas ALT levels and the PAC were predictors of HOMA2-IR.

CONCLUSION

Serum cortisol levels are associated with insulin secretion, and the PAC is associated with insulin resistance in patients with untreated type 2 diabetes. These findings suggest that aldosterone blockade may represent a potential therapeutic approach for reducing insulin resistance in patients with type 2 diabetes.

Explore potential immune-related targets of leeches in the treatment of type 2 diabetes based on network pharmacology and machine learning

Introduction

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder that poses a significant global health burden due to its profound effects on systemic physiological homeostasis. Without timely intervention, the disease can progress insidiously, leading to multisystem complications such as cardiovascular, renal, and neuropathic pathologies. Consequently, pharmacological intervention becomes crucial in managing the condition. Leeches have been traditionally used in Chinese medicine for their potential to inhibit the progression of T2DM and its associated complications; however, the specific mechanisms underlying their action and target pathways remain poorly understood. The objective of this study was to predict potential therapeutic targets of leeches in the treatment of T2DM.

Methods

We collected active components and targets associated with leeches from four online databases, while disease-related targets were sourced from the GeneCards and OMIM databases. Following this, we performed Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Gene expression data were obtained from the GSE184050 dataset. Important immune cell types were identified through immunoinfiltration analysis in conjunction with single sample enrichment analysis (ssGSEA). Additionally, weighted co-expression network analysis (WGCNA) was utilized to identify significantly associated genes. Finally, we employed LASSO regression, SVM-RFE, XGBoost, and random forest algorithms to further predict potential targets, followed by validation through molecular docking.

Results

Leeches may influence cellular immunity by modulating immune receptor activity, particularly through the activation of RGS10, CAPS2, and OPA1, thereby impacting the pathology of Type 2 Diabetes Mellitus (T2DM).

Discussion

However, it is important to note that our results lack experimental validation; therefore, further research is warranted to substantiate these findings.

Evaluation of glycemic status and subclinical atherosclerosis in familial hypercholesterolemia subjects with or without LDL receptor mutation

BACKGROUND

Familial hypercholesterolemia (FH) is a genetic condition characterized by elevated LDL-C and increased cardiovascular risk. Beyond LDL-C levels, the impact of genotype on glucose homeostasis has not been well evaluated. We aimed to evaluate the impact of genotype on glycemic status and on atherosclerotic injury in FH subjects.

METHODS

We conducted a cross-sectional study on 322 FH subjects not on lipid-lowering therapy and without history of cardiovascular disease. Biochemical and genetic analyses as well as vascular profile assessment were obtained from all subjects. The study population was divided into two groups according to genotype: LDL receptor (LDLR) group and non-LDLR (NLDLR) group.

RESULTS

The LDLR group exhibited a higher prevalence of low glycemic status (LGS) than the NLDLR group (44.1% vs. 26%, p < 0.01), whereas a high glycemic status (HGS) was more prevalent in the NLDLR group compared with LDLR group (74% vs. 55.9%, p < 0.01). The NLDLR group exhibited a higher prevalence of peripheral atherosclerotic plaques than the LDLR group (93.4% vs. 73%, p < 0.05), while coronary artery calcification (CAC) presence was more prevalent in the LDLR group compared with the NLDLR group (74.7% vs. 48%, p < 0.01). In a secondary analysis the study population was stratified into three groups based on LDLR genotype: NLDLR, LDLR defective, LDLR null groups. The prevalence of LGS progressively increased from the NLDLR to the LDLR null group, while HGS showed an inverse trend (p for trend < 0.05). Peripheral atherosclerotic plaque prevalence decreased from the NLDLR to the LDLR null group (p for trend < 0.05), while CAC prevalence increased progressively in the three groups (p for trend < 0.01). Logistic regression analysis showed that FH groups with an LDLR mutation were inversely associated with HGS (p for both < 0.01) and the LDLR null group exhibited the strongest association.

CONCLUSIONS

FH subjects with NLDLR mutations exhibited a worse glycemic profile, while null LDLR mutations showed the strongest inverse association with HGS. The integrations of genetic, lipid and glucose data could be useful to better identify the metabolic profile and the atherosclerosis distribution in FH subjects.

RESEARCH INSIGHTS

WHAT IS CURRENTLY KNOWN ABOUT THIS TOPIC?: Familial hypercholesterolemia (FH) is characterized by elevated LDL-C levels. LDLR null mutations protected pancreatic β-cells from cholesterol accumulation. NGS has improved FH diagnosis by analysis of all genes implicated in the lipid disorder. WHAT IS THE KEY RESEARCH QUESTION?: What is the impact of FH genotype (monogenic with or without LDLR mutation/polygenic) on glycemic status? WHAT IS NEW?: FH population was characterized by a heterogeneous glycemic profile according to LDLR mutation. LDL-C and plasma glucose could modulate the distribution of subclinical atherosclerosis. HOW MIGHT THIS STUDYINFLUENCE CLINICAL PRACTICE?: Genetic, lipid, glucose data could better identify the metabolic and atherosclerotic profiles in FH.

Nutritional knowledge, insulin resistance, and the risk of orthorexia nervosa: a comparative cross-sectional study among polish women

Background

The global rise in insulin resistance has led to an increased emphasis on dietary modifications as a primary strategy for its management. While such interventions are essential for improving metabolic health, they can also contribute to heightened nutritional knowledge. However, this increased focus on diet may inadvertently lead to the development of disordered eating patterns, including orthorexia nervosa. This study aimed to determine the level of nutritional knowledge regarding proper eating habits among women with insulin resistance and to assess the relationship between this knowledge and the risk of developing orthorexia nervosa.

Methods

The study was using the Computer-Assisted Web Interview method, involving 133 female participants from a primary care clinic in Katowice, Poland. Of these, 101 women had a medically confirmed diagnosis of insulin resistance, and 32 were healthy controls. Data were collected using an online survey, which included a demographic section, a 15-item questionnaire to assess nutritional knowledge, and the ORTO-15 tool to evaluate orthorexia nervosa risk.

Results

Women with insulin resistance had significantly higher Body Mass Index values and demonstrated greater nutritional knowledge than their healthy counterparts. However, 56.44% of women with insulin resistance were at risk of orthorexia nervosa, compared to 15.63% of the control group. Increased dietary knowledge in women with insulin resistance was also associated with a higher risk of developing orthorexic behavior.

Conclusion

The findings indicate that while women with insulin resistance benefit from improved nutritional knowledge in managing their condition, this knowledge may simultaneously increase their risk of developing orthorexia nervosa. Balancing the promotion of healthy eating habits with strategies that prevent the emergence of distorted eating behaviors is crucial. Future interventions should emphasize flexibility, psychological support, and individualized guidance to ensure both metabolic and mental well-being.

Associations of Vegetable and Potato Intakes With Markers of Type 2 Diabetes Risk in the AusDiab Cohort

CONTEXT

The associations of vegetable and potato intakes with type 2 diabetes (T2D) appear to be nuanced, depending on vegetable types and preparation method, respectively.

OBJECTIVE

We investigated the associations of total vegetable, vegetable subgroup, and potato intakes with (1) markers of T2D at baseline and (2) incident T2D cumulative over a 12-year follow-up period in Australian adults.

METHODS

Using data from the Australian Diabetes, Obesity and Lifestyle Study, intakes of vegetables and potatoes were assessed via a food frequency questionnaire at baseline. Associations between vegetable intake and (1) fasting plasma glucose (FPG), 2-hour postload plasma glucose (PLG), updated homeostasis model assessment of β-cell function (HOMA2-%β), HOMA2 of insulin sensitivity (HOMA2-%S), and fasting insulin levels at baseline; and (2) cumulative incident T2D at the end of 12-year follow-up were examined using generalized linear and Cox proportional hazards models, respectively.

RESULTS

In total, 8009 participants were included having median age of 52 years, and vegetable intake of 132 g/day. Higher intake of total vegetable, green leafy, yellow/orange/red, and moderate intakes of cruciferous vegetables was associated with lower PLG. Additionally, higher green leafy vegetable intake was associated with lower HOMA2-%β and serum insulin. Conversely, higher potato fries/chips intakes were associated with higher FPG, HOMA2-%β, serum insulin, and lower HOMA2-%S. Participants with moderate cruciferous vegetables intake had a 25% lower risk of T2D at the end of 12 years of follow-up.

CONCLUSION

A higher intake of vegetables, particularly green leafy vegetables, may improve while consuming potato fries/chips, but not potatoes prepared in a healthy way, may worsen glucose tolerance and insulin sensitivity. Our findings suggest a nuanced relationship between vegetable subgroups and their impact on glucose tolerance.

Individuation of a cut-off value of triglyceride-glucose index for incident diabetes mellitus in patients with essential hypertension

The prevalence of obesity and diabetes, risk factors for atherosclerotic vascular diseases, is increasing worldwide; therefore, it is desirable to early identify them to reduce cardiovascular events. Thus, we investigated whether the triglyceride-glucose index (TyG index), a new marker of insulin resistance, is associated with incident diabetes in patients with newly diagnosed arterial hypertension. We selected 585 patients with newly diagnosed arterial hypertension referred to our tertiary Clinic of Catanzaro University Hospital for the evaluation of their cardiometabolic risk profile. None of the patients had diabetes mellitus at enrollment and took any drug known to affect glucose metabolism. Patients underwent medical history collection, clinical examination and laboratory tests. The TyG index was calculated as the ln [fasting TG (mg/dl) × FPG (mg/dl)/2], as previously suggested. During the follow-up [mean 8.5 years (range 3.1-10.7)], there were 78 new cases of incident diabetes (1.57% patient-year). Patients who developed diabetes mellitus were older and had a higher body mass index (BMI), baseline blood pressure, fasting glucose, insulin, homeostatis model sssessment (HOMA) index, triglyceride, creatinine and hs-CRP mean values, while estimated glomerular filtration rate values were lower. At the Cox regression analysis, covariates significantly associated with incident diabetes were: BMI (HR = 2.842, 95%CI = 2.299-3.514), TyG index (HR = 2.392, 95%CI = 1.745-3.192), age (HR = 1.944, 95%CI = 1.527-2.474), hs-CRP (HR = 1.409, 95%CI = 1.153-1.722), and HOMA (HR = 1.325, 95%CI = 1,079-1.756). The best estimated cut-off value of TyG index in predicting diabetes was 4.71. In addition, we documented a significant relationship between TyG index and HOMA (r = 0.575; p < 0.0001). Present data demonstrate that TyG index, a simple and cost-effective marker of insulin resistance, is useful in predicting incident diabetes in patients with arterial hypertension.

Evolving Characteristics of Type 2 Diabetes Mellitus in East Asia

In East Asians, type 2 diabetes mellitus (T2DM) is primarily characterized by significant defects in insulin secretion and comparatively low insulin resistance. Recently, the prevalence of T2DM has rapidly increased in East Asian countries, including Korea, occurring concurrently with rising obesity rates. This trend has led to an increase in the average body mass index among East Asian T2DM patients, highlighting the influence of insulin resistance in the development of T2DM within this group. Currently, the incidence of T2DM in Korea is declining, which may indicate potential adaptive changes in insulin secretory capacity. This review focuses on the changing epidemiology of T2DM in East Asia, with a particular emphasis on the characteristics of peak functional β-cell mass.

Pancreatic beta cell function and insulin resistance profiles in first-degree relatives of patients with prediabetes and type 2 diabetes

AIMS

To evaluate insulin secretion and insulin resistance profiles in individuals with family history of prediabetes and type 2 diabetes.

METHODS

This was a cross-sectional study to evaluate clinical and metabolic profiles between individuals with type 2 diabetes, prediabetes and their relatives. There were 911 subjects divided into five groups: (i) normoglycemic (NG), (ii) type 2 diabetes, (iii) prediabetes, (iv) first-degree relatives of patients with type 2 diabetes (famT2D), and (v) first-degree relatives of patients with prediabetes (famPD); anthropometrical, biochemical and nutritional evaluation, as well as insulin resistance and pancreatic beta cell function measurement was performed by oral glucose tolerance to compare between groups.

RESULTS

The most prevalent type 2 diabetes risk factors were dyslipidemia (81%), family history of type 2 diabetes (76%), central obesity (73%), male sex (63%), and sedentary lifestyle (60%), and most of them were progressively associated to prediabetes and type 2 diabetes groups. Insulin sensitivity was lower in famT2D groups in comparison to NG group (p < 0.0001). FamPD and famT2D had a 10% lower pancreatic beta cell function (DI) than the NG group (NG group 2.78 ± 1.0, famPD 2.5 ± 0.85, famT2D 2.4 ± 0.75, p˂0.001).

CONCLUSIONS

FamPD and famT2D patients had lower pancreatic beta cell function than NG patients, highlighting that defects in insulin secretion and insulin sensitivity appear long time before the development of hyperglycemia in patients genetically predisposed.

Association of dietary decanoic acid intake with diabetes or prediabetes: an analysis from NHANES 2005-2016

Background

With the increasing prevalence of prediabetes and diabetes, exploring dietary factors associated with prediabetes and diabetes has become a global health research priority. This study aimed to assess the relationship between dietary decanoic acid (DDA) intake and the risk of diabetes and prediabetes.

Methods

Data from the National Health and Nutrition Examination Survey (NHANES) 2005-2016 included 11,477 adult participants. DDA intake was assessed through two 24-h dietary recalls and participants were grouped according to the diagnostic criteria for diabetes and prediabetes. Multivariate regression models were applied to analyze the relationship between DDA intake and diabetes and prediabetes, with subgroup analyses conducted to explore potential interactions.

Results

Dietary decanoic acid intake was significantly negatively associated with the risk of diabetes. In the fully adjusted model, each 1 g/day increase in DDA intake was associated with a 19% reduction in the odds of developing diabetes from prediabetes (OR = 0.81, 95% CI: 0.68-0.96, p = 0.015) and this negative association was more pronounced in individuals with higher education level (P for interaction = 0.006). Compared with the DDA intake ≤0.18 g/day, DDA intake >0.58 g/day is related to reduced risk of progression to diabetes in prediabetic patients. However, the relationship between DDA intake and the risk of prediabetes was not statistically significant in the fully adjusted model (OR = 0.95, 95% CI: 0.84-1.07, p = 0.404).

Conclusion

This study found that higher DDA intake may be associated with lower prevalence of diabetes among prediabetic population, and high education level strengthen this relationship.

One-Hour Postload Glucose Is a More Sensitive Marker of Impaired β-Cell Function Than Two-Hour Postload Glucose

There is evidence that 1-h plasma glucose (PG) concentration during the 75-g oral glucose tolerance test (OGTT) is superior to 2-h PG level in predicting diabetes. We investigated the characteristics of insulin sensitivity and β-cell function behind this observation. After age, sex, and BMI matching, 496 study participants selected from 3,965 individuals without diabetes who were at high risk of type 2 diabetes in a tertiary medical center were categorized into four groups in a 1:1:1:1 ratio based on OGTT results: 1) 1-h PG level <8.6 mmol/L and 2-h PG level <7.8 mmol/L (normal glucose tolerance [NGT]/1h-normal); 2) 1-h PG level ≥8.6 mmol/L and 2-h level <7.8 mmol/L (NGT/1h-high); 3) 1-h PG level <8.6 mmol/L and 2-h level ≥7.8 mmol/L (impaired glucose tolerance [IGT]/1h-normal); and 4) 1 h PG level ≥8.6 mmol/L and 2-h level ≥7.8 mmol/L. Compared with participants with IGT/1h-normal, those with NGT/1h-high had a similar extent of insulin resistance but lower early-phase insulin secretion. Additionally, participants with NGT/1h-high had a lower disposition index at both 0-30 min and 0-120 min than those with IGT/1h-normal. The fitted regression line relating PG to log-transformed disposition index (0-30 min and 0-120 min) was significantly steeper for 1-h than 2-h PG. In conclusion, 1-h PG seemed to be more sensitive to the deterioration in β-cell function than was 2-h PG. The use of 1-h PG may identify individuals at high risk of type 2 diabetes at an earlier stage.

ARTICLE HIGHLIGHTS

Leupaxin promotes hepatic gluconeogenesis and glucose metabolism by coactivation with hepatic nuclear factor 4α

BACKGROUND

As the primary source of glucose during fasting, hepatic gluconeogenesis is rigorously regulated to maintain euglycemia. Abnormal gluconeogenesis in the liver can lead to hyperglycemia, a key diagnostic marker and the primary pathological contributor to type 2 diabetes (T2D) and metabolic disorders. Hepatic nuclear factor-4 (HNF4α) is an important regulator of gluconeogenesis. In this study, we identify leupaxin (LPXN) as a novel coactivator for HNF4α. Although previous studies have shown that LPXN is highly correlated with cancer types such as B-cell differentiation and hepatocellular carcinoma progression, the role of LPXN in gluconeogenesis remains unknown.

METHODS

We initially used protein pull-down assays, mass spectrometry and luciferase assays to identify the coactivator that interacts with HNF4α in gluconeogenesis. We further leveraged cell cultures and mouse models to validate the functional importance of molecular pathway during gluconeogenesis by using adenovirus-mediated overexpression and adeno-associated virus shRNA-mediated knockdown both in vivo and ex vivo, such as in ob/db/DIO mice, HepG2 and primary hepatocytes. Following, we used CUT&Tag and chip qPCR to identify the LPXN-mediated mechanisms underlying the observed abnormal gluconeogenesis. Additionally, we assessed the translational relevance of our findings using human liver tissues from both healthy donors and patients with obesity/type 2 diabetes.

RESULTS

We found that LPXN interacts with HNF4α to participate in gluconeogenesis. Knockdown of LPXN expression in the liver effectively enhanced glucose metabolism, while its overexpression in the liver effectively inhibited it. Mechanistically, LPXN could translocate into the nucleus and was essential for regulating gluconeogenesis by binding to the PEPCK promoter, which controlled the expression of an enzyme involved in gluconeogenesis, mainly through the Gcg-cAMP-PKA pathway. Additionally, LPXN expression was found to be increased in the livers of patients with steatosis and diabetes, supporting a pathological role of LPXN.

CONCLUSIONS

Taken together, our study provides evidence that LPXN plays a critical role in modulating hepatic gluconeogenesis, thereby reinforcing the fact that targeting LPXN may be a potential approach for the treatment of diabetes and metabolic disorders.

Leukotriene B4 is elevated in diabetes and promotes ventricular arrhythmogenesis in guinea pig

Diabetes (DM) patients have an increased risk (~50%) for sudden cardiac death (SCD), mostly as a result of ventricular arrhythmias. The molecular mechanisms involved remain partially defined. The potent proinflammatory lipid mediator leukotriene (LT) B4, is pathologically elevated in DM compared to nondiabetic patients, resulting in increased LTB4 accumulation in heart, leading to an increased risk for life-threatening proarrhythmic signatures. We used electrophysiology, immunofluorescence, and confocal microscopy approaches to evaluate LTB4 cellular effects in guinea pig heart and ventricular myocytes. We have observed that LTB4 is increased in multiple mouse models (C57BL/6 J/Lepob/ob and PANIC-ATTAC) of DM, promotes profound cellular arrhythmogenesis (spontaneous beats and early after depolarizations, EADs), and severely depresses the rapidly activating delayed rectifier K current (hERG1/IKr) density in HEK293 cells and guinea pig ventricular myocytes. We have further found that guinea pigs challenged with LTB4 displayed a significantly prolonged QT interval, and that this can be prevented with LTB4R inhibition, suggesting that preventing such LTB4R effects may be therapeutically beneficial in DM. Our data suggests that a further elucidation of LTB4 vulnerable substrates, and how this leads to ventricular arrhythmias, is likely to lead to continued improvements in management options, and the development of new therapies for prevention of SCD in DM patients.

Polycystic ovary syndrome: Criteria, phenotypes, race and ethnicity

Background

Polycystic ovary syndrome (PCOS) is a complex endocrinopathy, which leads to ovulation dysfunction and infertility, as well as metabolic and mental disorders. Women with PCOS exhibit several characteristic symptoms, with marked heterogeneity across different races and ethnicities.

Methods

In this review, the author outlines the phenotypic disparities of PCOS among various racial and ethnic populations. First, the prevalence of major symptoms in different racial and ethnic groups with PCOS is summarized. Next, the effects of four phenotypes, derived from the Rotterdam criteria for PCOS, on metabolic and reproductive features are recapitulated.

Main Findings

A growing body of evidence suggests that East Asian populations exhibit less hirsutism and adiposity compared with other groups. However, hirsutism is more prevalent in South Asian, Middle Eastern, and Hispanic populations. Hispanic and African American populations have more frequent obesity and insulin resistance. With regard to the association between mental disorders and racial and ethnic differences, limited studies exist; therefore, no conclusions can be drawn.

Conclusion

Race and ethnicity-specific factors related to PCOS must be considered in clinical practice. The diagnostic criteria of PCOS should be specific to race and ethnicity to avoid missing treatment opportunities.

Sirt1-mediated deacetylation of PGC-1α alleviated hepatic steatosis in type 2 diabetes mellitus via improving mitochondrial fatty acid oxidation

Being activated by deacetylation, peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) has become an important regulator of metabolic-related diseases. The activation of Sirtuin 1 (Sirt1) by resveratrol was likely to deacetylate PGC-1α. However, the role of deacetylated PGC-1α in the alleviation of activated Sirt1 on type 2 diabetes mellitus (T2DM)-related fatty liver disease (FLD) remained unexplored. The aim of this study was to investigate the potential impact of Sirt1-mediated deacetylation of PGC-1α on T2DM-associated FLD and its underlying mechanisms. Our findings revealed that, along with the decreased Sirt1, the levels of acetylated PGC-1α were up-regulated in hepatocytes co-stimulated with high glucose (HG) and free fatty acids (FFA). Down-regulated Sirt1 inactivated PGC-1α by inhibiting its deacetylation, while activating Sirt1 improved hepatic injury by reducing lipid droplet accumulation through the deacetylation of PGC-1α. However, the beneficial effects of Sirt1 activation on hepatic steatosis were inhibited by PGC-1α antagonist in vitro. Mechanistically, activating Sirt1 enhanced mitochondrial function by promoting PGC-1α activity, thereby facilitating hepatic fatty acid oxidation (FAO). In conclusion, Sirt1-mediated deacetylation of PGC-1α mitigated hepatic lipotoxicity by enhancing mitochondrial FAO, which contributed to the restoration of mitochondrial function in T2DM. The activation of Sirt1-mediated PGC-1α deacetylation might represent a promising therapeutic approach for T2DM-associated FLD.

Carvacrol is potential molecule for diabetes treatment

Diabetes is an important chronic disease that can lead to various negative consequences and complications. In recent years, several new alternative treatments have been developed to improve diabetes. Carvacrol found in essential oils of numerous plant species and has crucial potential effects on diabetes. The anti-diabetic effects of carvacrol have also been comprehensively studied in diabetic animal and cell models. In addition, carvacrol could improve diabetes through affecting diabetes-related enzymes, insulin resistance, insulin sensitivity, glucose uptake, anti-oxidant, and anti-inflammatory mechanisms. The use of carvacrol alone or in combination with anti-diabetic therapies could show a significant potential effect in the treatment of diabetes. This review contributes an overview of the effect of carvacrol in diabetes and anti-diabetic mechanisms.

Recent Glycemia Is a Major Determinant of β-Cell Function in Type 2 Diabetes Mellitus

BACKGRUOUND

Progressive deterioration of β-cell function is a characteristic of type 2 diabetes mellitus (T2DM). We aimed to investigate the relative contributions of clinical factors to β-cell function in T2DM.

METHODS

In a T2DM cohort of 470 adults (disease duration 0 to 41 years), β-cell function was estimated using insulinogenic index (IGI), disposition index (DI), oral disposition index (DIO), and homeostasis model assessment of β-cell function (HOMA-B) derived from a 75 g oral glucose tolerance test (OGTT). The relative contributions of age, sex, disease duration, body mass index, glycosylated hemoglobin (HbA1c) levels (at the time of the OGTT), area under the curve of HbA1c over time (HbA1c AUC), coefficient of variation in HbA1c (HbA1c CV), and antidiabetic agents use were compared by standardized regression coefficients. Longitudinal analyses of these indices were also performed.

RESULTS

IGI, DI, DIO, and HOMA-B declined over time (P<0.001 for all). Notably, HbA1c was the most significant factor affecting IGI, DI, DIO, and HOMA-B in the multivariable regression analysis. Compared with HbA1c ≥9%, DI was 1.9-, 2.5-, 3.7-, and 5.5-fold higher in HbA1c of 8%-<9%, 7%-<8%, 6%-<7%, and <6%, respectively, after adjusting for confounding factors (P<0.001). Conversely, β-cell function was not affected by the type or duration of antidiabetic agents, HbA1c AUC, or HbA1c CV. The trajectories of the IGI, DI, DIO, and HOMA-B mirrored those of HbA1c.

CONCLUSION

β-Cell function declines over time; however, it is flexible, being largely affected by recent glycemia in T2DM.

Senoinflammation as the underlying mechanism of aging and its modulation by calorie restriction

Senoinflammation is characterized by an unresolved low-grade inflammatory process that affects multiple organs and systemic functions. This review begins with a brief overview of the fundamental concepts and frameworks of senoinflammation. It is widely involved in the aging of various organs and ultimately leads to progressive systemic degeneration. Senoinflammation underlying age-related inflammation, is causally related to metabolic dysregulation and the formation of senescence-associated secretory phenotype (SASP) during aging and age-related diseases. This review discusses the biochemical evidence and molecular biology data supporting the concept of senoinflammation and its regulatory processes, highlighting the anti-aging and anti-inflammatory effects of calorie restriction (CR). Experimental data from CR studies demonstrated effective suppression of various pro-inflammatory cytokines and chemokines, lipid accumulation, and SASP during aging. In conclusion, senoinflammation represents the basic mechanism that creates a microenvironment conducive to aging and age-related diseases. Furthermore, it serves as a potential therapeutic target for mitigating aging and age-related diseases.

MuscleMap: An Open-Source, Community-Supported Consortium for Whole-Body Quantitative MRI of Muscle

Disorders affecting the neurological and musculoskeletal systems represent international health priorities. A significant impediment to progress in trials of new therapies is the absence of responsive, objective, and valid outcome measures sensitive to early disease changes. A key finding in individuals with neuromuscular and musculoskeletal disorders is the compositional changes to muscles, evinced by the expression of fatty infiltrates. Quantification of skeletal muscle composition by MRI has emerged as a sensitive marker for the severity of these disorders; however, little is known about the composition of healthy muscles across the lifespan. Knowledge of what is 'typical' age-related muscle composition is essential to accurately identify and evaluate what is 'atypical'. This innovative project, known as the MuscleMap, will achieve the first important steps towards establishing a world-first, normative reference MRI dataset of skeletal muscle composition with the potential to provide valuable insights into various diseases and disorders, ultimately improving patient care and advancing research in the field.

Protein posttranslational modifications in metabolic diseases: basic concepts and targeted therapies

Metabolism-related diseases, including diabetes mellitus, obesity, hyperlipidemia, and nonalcoholic fatty liver disease, are becoming increasingly prevalent, thereby posing significant threats to human health and longevity. Proteins, as the primary mediators of biological activities, undergo various posttranslational modifications (PTMs), including phosphorylation, ubiquitination, acetylation, methylation, and SUMOylation, among others, which substantially diversify their functions. These modifications are crucial in the physiological and pathological processes associated with metabolic disorders. Despite advancements in the field, there remains a deficiency in contemporary summaries addressing how these modifications influence processes of metabolic disease. This review aims to systematically elucidate the mechanisms through which PTM of proteins impact the progression of metabolic diseases, including diabetes, obesity, hyperlipidemia, and nonalcoholic fatty liver disease. Additionally, the limitations of the current body of research are critically assessed. Leveraging PTMs of proteins provides novel insights and therapeutic targets for the prevention and treatment of metabolic disorders. Numerous drugs designed to target these modifications are currently in preclinical or clinical trials. This review also provides a comprehensive summary. By elucidating the intricate interplay between PTMs and metabolic pathways, this study advances understanding of the molecular mechanisms underlying metabolic dysfunction, thereby facilitating the development of more precise and effective disease management strategies.

Advances in the Insulin-Heart Axis: Current Therapies and Future Directions

The insulin-heart axis plays a pivotal role in the pathophysiology of cardiovascular disease (CVD) in insulin-resistant states, including type 2 diabetes mellitus. Insulin resistance disrupts glucose and lipid metabolism, leading to systemic inflammation, oxidative stress, and atherogenesis, which contribute to heart failure (HF) and other CVDs. This review was conducted by systematically searching PubMed, Scopus, and Web of Science databases for peer-reviewed studies published in the past decade, focusing on therapeutic interventions targeting the insulin-heart axis. Studies were selected based on their relevance to insulin resistance, cardiovascular outcomes, and the efficacy of pharmacologic treatments. Key findings from the review highlight the efficacy of lifestyle modifications, such as dietary changes and physical activity, which remain the cornerstone of managing insulin resistance and improving cardiovascular outcomes. Moreover, pharmacologic interventions, such as metformin, sodium-glucose cotransporter 2 inhibitors, glucagon-like peptide-1 receptor agonists, and dipeptidyl peptidase-4 inhibitors, have shown efficacy in reducing cardiovascular risk by addressing metabolic dysfunction, reducing inflammation, and improving endothelial function. Furthermore, emerging treatments, such as angiotensin receptor-neprilysin inhibitors, and mechanical interventions like ventricular assist devices offer new avenues for managing HF in insulin-resistant patients. The potential of these therapies to improve left ventricular ejection fraction and reverse pathological cardiac remodeling highlights the importance of early intervention. However, challenges remain in optimizing treatment regimens and understanding the long-term cardiovascular effects of these agents. Future research should focus on personalized approaches that integrate lifestyle and pharmacologic therapies to effectively target the insulin-heart axis and mitigate the burden of cardiovascular complications in insulin-resistant populations.

Diabetic Kidney Disease: Contribution of Phenyl Sulfate Derived from Dietary Tyrosine upon Gut Microbiota Catabolism

Deranged gut microbiota can release increased levels of uremic toxins leading to exacerbated kidney injury. In diabetic kidney disease (DKD), phenyl sulfate (PS) derived from tyrosine catabolism by gut microbiota has been demonstrated to be both an early diagnostic marker and a therapeutic target. In this perspective article, we summarize PS generation pathways and recent findings on PS and kidney injury in DKD. Increasing evidence has shown that the underlying mechanisms of PS-induced kidney injury mainly involve oxidative stress, redox imbalance, and mitochondrial dysfunction, which all may be targeted to attenuate PS-induced kidney injury. For future research directions, we think that a deeper understanding of the pathogenic role of PS in kidney injury using a variety of diabetic animal models should be investigated. Moreover, we also suggest beneficial approaches that could be used to mitigate the deleterious effect of PS on the kidney. These approaches include caloric restriction, tyrosine restriction, and administration of ketogenic drugs, ketogenic diets or natural products; all of which should be conducted under obese and diabetic conditions.

Salvianolic acid A attenuates non-alcoholic fatty liver disease by regulating the AMPK-IGFBP1 pathway

Non-alcoholic fatty liver disease (NAFLD) affects approximately a quarter of the population and, to date, there is no approved drug therapy for this condition. Individuals with type 2 diabetes mellitus (T2DM) are at a significantly elevated risk of developing NAFLD, underscoring the urgency of identifying effective NAFLD treatments for T2DM patients. Salvianolic acid A (SAA) is a naturally occurring phenolic acid that is an important component of the water-soluble constituents isolated from the roots of Salvia miltiorrhiza Bunge. SAA has been demonstrated to possess anti-inflammatory and antioxidant stress properties. Nevertheless, its potential in ameliorating diabetes-associated NAFLD has not yet been fully elucidated. In this study, diabetic ApoE-/- mice were employed to establish a NAFLD model via a Western diet. Following this, they were treated with different doses of SAA (10 mg/kg, 20 mg/kg) via gavage. The study demonstrated a marked improvement in liver injury, lipid accumulation, inflammation, and the pro-fibrotic phenotype after the administration of SAA. Additionally, RNA-seq analysis indicated that the primary pathway by which SAA alleviates diabetes-induced NAFLD involves the cascade pathways of lipid metabolism. Furthermore, SAA was found to be effective in the inhibition of lipid accumulation, mitochondrial dysfunction and ferroptosis. A functional enrichment analysis of RNA-seq data revealed that SAA treatment modulates the AMPK pathway and IGFBP-1. Further experimental results demonstrated that SAA is capable of inhibiting lipid accumulation through the activation of the AMPK pathway and IGFBP-1.

Hyperglycemia and cognitive impairments anticipate the onset of an overt type 2 diabetes-like phenotype in TALLYHO/JngJ mice

Type 2 Diabetes mellitus (T2DM) is a metabolic disorder characterized by chronic hyperglycemia, resulting from deficits in insulin secretion, insulin action, or both. Whilst the role of insulin in the peripheral nervous system has been ascertained in countless studies, its role in the central nervous system (CNS) is emerging only recently. Brain insulin has been lately associated with brain disorders like Alzheimer's disease, obsessive compulsive disorder, and attention deficit hyperactivity disorder. Thus, understanding the role of insulin as a common risk factor for mental and somatic comorbidities may disclose novel preventative and therapeutic approaches. We evaluated general metabolism (glucose tolerance, insulin sensitivity, energy expenditure, lipid metabolism, and polydipsia) and cognitive capabilities (attention, cognitive flexibility, and memory), in adolescent, young adult, and adult male and female TALLYHO/JngJ mice (TH, previously reported to constitute a valid experimental model of T2DM due to impaired insulin signaling). Adult TH mice have also been studied for alterations in gut microbiota diversity and composition. While TH mice exhibited profound deficits in cognitive flexibility and altered glucose metabolism, we observed that these alterations emerged either much earlier (males) or independent of (females) a comprehensive constellation of symptoms, isomorphic to an overt T2DM-like phenotype (insulin resistance, polydipsia, higher energy expenditure, and altered lipid metabolism). We also observed significant sex-dependent alterations in gut microbiota alpha diversity and taxonomy in adult TH mice. Deficits in insulin signaling may represent a common risk factor for both T2DM and CNS-related deficits, which may stem from (partly) independent mechanisms.

The application of predictive value of diabetes autoantibody profile combined with clinical data and routine laboratory indexes in the classification of diabetes mellitus

Objective

Currently, distinct use of clinical data, routine laboratory indicators or the detection of diabetic autoantibodies in the diagnosis and management of diabetes mellitus is limited. Hence, this study was aimed to screen the indicators, and to establish and validate a multifactorial logistic regression model nomogram for the non-invasive differential prediction of type 1 diabetes mellitus.

Methods

Clinical data, routine laboratory indicators, and diabetes autoantibody profiles of diabetic patients admitted between September 2018 and December 2022 were retrospectively analyzed. Logistic regression was used to select the independent influencing factors, and a prediction nomogram based on the multiple logistic regression model was constructed using these independent factors. Moreover, the predictive accuracy and clinical application value of the nomogram were evaluated using Receiver Operating Characteristic (ROC) curves, calibration curves, decision curve analysis (DCA), and clinical impact curves (CIC).

Results

A total of 522 diabetic patients were included in this study. These patients were randomized into training and validation sets in a 7:3 ratio. The predictors screened included age, prealbumin (PA), high-density lipoprotein cholesterol (HDL-C), islet cells autoantibodies (ICA), islets antigen 2 autoantibodies (IA-2A), glutamic acid decarboxylase antibody (GADA), and C-peptide levels. Based on these factors, a multivariate model nomogram was constructed, which had an Area Under Curve (AUC) of 0.966 and 0.961 for the training set and validation set, respectively. Subsequently, the calibration curves demonstrated a strong accuracy of the graph; the DCA and CIC results indicated that the graph could be used as a non-invasive valid predictive tool for the differential diagnosis of type 1 diabetes mellitus, clinically.

Conclusion

The established prediction model combining patient's age, PA, HDL-C, ICA, IA-2A, GADA, and C-peptide can assist in differential diagnosis of type 1 diabetes mellitus and type 2 diabetes mellitus and provides a basis for the clinical as well as therapeutic management of the disease.

Effect of circadian clock disruption on type 2 diabetes

Introduction

Type 2 diabetes (T2D) is the predominant form of diabetes mellitus and is among the leading causes of death with an increasing prevalence worldwide. However, the pathological mechanism underlying T2D remains complex and unclear. An increasing number of studies have suggested an association between circadian clock disruption and high T2D prevalence.

Method

This review explores the physiological and genetic evidence underlying T2D symptoms associated with circadian clock disturbances, including insulin secretion and glucose metabolism.

Results and Discussion

Notably, circadian clock disruption reduces insulin secretion and insulin sensitivity and negatively affects glucose homeostasis. The circadian clock regulates the hypothalamic-pituitary-adrenal axis, an important factor that regulates glucose metabolism and influences T2D progression. Therefore, circadian clock regulation is an attractive, novel therapeutic approach for T2D, and various circadian clock stabilizers play therapeutic roles in T2D. Lastly, this review suggests novel therapeutic and preventive approaches using circadian clock regulators for T2D.

Extract of Phyllanthus emblica L. fruit stimulates basal glucose uptake and ameliorates palmitate-induced insulin resistance through AMPK activation in C2C12 myotubes

BACKGROUND

The fruit of Phyllanthus emblica L., a traditional medicine in China and India, is used to treat diabetes mellitus. Its water extract (WEPE) has demonstrated hypoglycemic effects in diabetic rats, but its mechanisms on glucose utilization and insulin resistance in skeletal muscle remain unclear. Therefore, this study aims to investigate the effects and underlying mechanisms of WEPE on glucose utilization and insulin resistance using C2C12 myotubes.

METHODS

Effects of WEPE on glucose uptake, GLUT4 translocation, and AMPK and AKT phosphorylation were investigated in C2C12 myotubes and palmitate-treated myotubes. An AMPK inhibitor and siRNA were used to explore the mechanisms of WEPE. Glucose uptake was determined using a 2-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino)-2-deoxyglucose (2-NBDG) uptake assay, and protein expression and GLUT4 translocation were assessed via western blotting.

RESULTS

In normal myotubes, WEPE significantly stimulated glucose uptake and GLUT4 translocation to the plasma membrane at concentrations of 125 and 250 µg/mL. This was accompanied by an increase in the phosphorylation of AMPK and its downstream targets. However, both compound C and AMPK siRNA blocked the WEPE-induced GLUT4 translocation and glucose uptake. Moreover, pretreatment with STO-609, a calcium/calmodulin-dependent protein kinase kinase β (CaMKKβ) inhibitor, inhibited WEPE-induced AMPK phosphorylation and attenuated the WEPE-stimulated glucose uptake and GLUT4 translocation. In myotubes treated with palmitate, WEPE prevented palmitate-induced insulin resistance by enhancing insulin-mediated glucose uptake and AKT phosphorylation. It also restored the insulin-mediated translocation of GLUT4 from cytoplasm to membrane. However, these effects of WEPE on glucose uptake and GLUT4 translocation were blocked by pretreatment with compound C.

CONCLUSIONS

WEPE significantly stimulated basal glucose uptake though CaMKKβ/AMPK pathway and markedly ameliorated palmitate-induced insulin resistance by activating the AMPK pathway in C2C12 myotubes.

Nutrient quality in dietary therapy for diabetes and diabetic kidney disease

Dietary therapy is crucial for diabetes care with the aim of preventing the onset and progression of diabetes and its complications. The traditional approach to dietary therapy for diabetes has primarily focused on restricting the intake of the three major nutrients and rigorously controlling blood glucose levels. However, advancements in nutritional science have shown that within the three major nutrients - carbohydrates, proteins and lipids - there exist multiple types, each with distinct impacts on type 2 diabetes and its complications, sometimes even showing conflicting effects. In light of this, the present review shifts its focus from the quantity to the quality of the three major nutrients. It aims to provide an overview of how the differences in nutrient quality can influence onset and progression of type 2 diabetes and diabetic kidney disease, highlighting the diverse effects and, at times, contradictory impacts associated with each nutrient type.

IRTKS promotes osteogenic differentiation by inhibiting PTEN phosphorylation

Insulin stimulates osteoblast proliferation and differentiation as an anabolic agent in bone. Insulin Receptor Tyrosine Kinase Substrate (IRTKS) is involved in insulin signaling as an adapter for insulin receptors (IR). Here, we showed that IRTKS levels were significantly decreased in bone marrow mesenchymal stem cells (BMSCs) derived from the bone marrow of patients with osteoporosis. Based on relevant experiments, we observed that IRTKS promoted the proliferation, migration, and osteoblast differentiation of BMSCs and MC3T3-E1 cells. In addition, we identified a Phosphatase and Tensin homolog deleted on chromosome 10 (PTEN) as a potential active substrate of IRTKS. We demonstrated a direct interaction between IRTKS and PTEN using co-immunoprecipitation. Subsequently, we confirmed that the SH3 domain of IRTKS directly binds to the C-terminal tail of PTEN. Further experimental results demonstrated that PTEN attenuated the promoting effects of IRTKS on the proliferation, migration, and osteoblast differentiation of BMSCs and MC3T3-E1 cells. In conclusion, this study suggests that IRTKS contributes to osteogenic differentiation by inhibiting PTEN phosphorylation and provides a potential therapeutic target for osteoporosis patients.

Gonadal dysfunction in women with diabetes mellitus

It is well known that both type 1 and type 2 diabetes mellitus (DM) are related to increased risk for cardiovascular (CV) and chronic kidney disease (CKD). However, besides these prominently presented complications, DM has also been associated with reproductive dysfunctions. It seems that these disorders are met in up to 40% of women with DM and consist of delayed menarche, all types of menstrual disorders, such as amenorrhea, oligomenorrhea, menstrual irregularity, as well as menorrhagia, infertility, characteristics of polycystic ovary syndrome (PCOS) and early (or rarely late) menopause. In type 1 DM (T1DM), insulin treatment, although it has reduced the rates of insulinopenic-induced hypogonadotropic hypogonadism, an entity commonly presented in many women with the disease in the past decades, when it is used in excess it can also promote hyperandrogenism. Regarding type 2 DM (T2DM), insulin resistance (IR) and hyperinsulinemia have mainly been implicated in the pathogenesis of reproductive dysfunctions, as insulin can act as gonadotropin on the theca cells of the ovary and can lead to hyperandrogenism and inhibition of proper ovulation. This review aims to detail the reproductive dysfunctions associated with DM and provide scientific data to enlighten the underlying pathogenetic mechanisms.

Current type 2 diabetes guidelines: Individualized treatment and how to make the most of metformin

Evidence-based guidelines provide the premise for the delivery of quality care to preserve health and prevent disabilities and premature death. The systematic gathering of observational, mechanistic and experimental data contributes to the hierarchy of evidence used to guide clinical practice. In the field of diabetes, metformin was discovered more than 100 years ago, and with 60 years of clinical use, it has stood the test of time regarding its value in the prevention and management of type 2 diabetes. Although some guidelines have challenged the role of metformin as the first-line glucose-lowering drug, it is important to point out that the cardiovascular-renal protective effects of sodium-glucose co-transporter-2 inhibitors and glucagon-like peptide-1 receptor agonists were gathered from patients with type 2 diabetes, the majority of whom were treated with metformin. Most national, regional and international guidelines recommend metformin as a foundation therapy with emphasis on avoidance of therapeutic inertia and early attainment of multiple treatment goals. Moreover, real-world evidence has confirmed the glucose-lowering and cardiovascular-renal benefits of metformin accompanied by an extremely low risk of lactic acidosis. In patients with type 2 diabetes and advanced chronic kidney disease (estimated glomerular filtration rate 15-30 mL/min/1.73m2), metformin discontinuation was associated with an increased risk of cardiovascular-renal events compared with metformin persistence. Meanwhile, it is understood that microbiota, nutrients and metformin can interact through the gut-brain-kidney axis to modulate homeostasis of bioactive molecules, systemic inflammation and energy metabolism. While these biological changes contribute to the multisystem effects of metformin, they may also explain the gastrointestinal side effects and vitamin B12 deficiency associated with metformin intolerance. By understanding the interactions between metformin, foods and microbiota, healthcare professionals are in a better position to optimize the use of metformin and mitigate potential side effects. The United Kingdom Prospective Diabetes Study and the Da Qing Diabetes Prevention Program commenced 40 years ago provided the first evidence that type 2 diabetes is preventable and treatable. To drive real-world impact from this evidence, payors, practitioners and planners need to co-design and implement an integrated, data-driven, metformin-based programme to detect people with undiagnosed diabetes and prediabetes (intermediate hyperglycaemia), notably impaired glucose tolerance, for early intervention. The systematic data collection will create real-world evidence to bring out the best of metformin and make healthcare sustainable, affordable and accessible.

Impact of Diabetes Mellitus on Outcomes in Patients with Left Ventricular Assist Devices

Heart failure (HF) represents a significant health burden in the United States, resulting in substantial mortality and healthcare costs. Through the array of treatment options available, including lifestyle modifications, medications, and implantable devices, HF management has evolved. Left ventricular assist devices (LVADs) have emerged as a crucial intervention, particularly in patients with advanced HF. However, the prevalence of comorbidities such as diabetes mellitus (DM) complicates treatment outcomes. By elucidating the impact of DM on LVAD outcomes, this review aims to inform clinical practice and enhance patient care strategies for individuals undergoing LVAD therapy. Patients with DM have higher rates of hypertension, dyslipidemia, peripheral vascular disease, and renal dysfunction, posing challenges to LVAD management. The macro/microvascular changes that occur in DM can lead to cardiomyopathy and HF. Glycemic control post LVAD implantation is a critical factor affecting patient outcomes. The recent literature has shown significant decreases in hemoglobin A1c following LVAD implantation, representing a possible bidirectional relationship between DM and LVADs; however, the clinical significance of this decrease is unclear. Furthermore, while some studies show increased short- and long-term mortality in patients with DM after LVAD implantation, there still is no literature consensus regarding either mortality or major adverse outcomes in DM patients.

Palmitic acid induces β-cell ferroptosis by activating ceramide signaling pathway

Individuals with type 2 diabetes mellitus frequently display heightened levels of palmitic acid (PA) in their serum, which may lead to β-cell damage. The involvement of ferroptosis, a form of oxidative cell death in lipotoxic β-cell injury remains uncertain. Here, we have shown that PA induces intracellular lipid peroxidation, increases intracellular Fe2+ content and decreases intracellular glutathione peroxidase 4 (GPX4) expression. Furthermore, PA causes distinct changes in pancreatic islets and INS-1 cells, such as mitochondrial atrophy and increased membrane density. Furthermore, the presence of the ferroptosis inhibitor has a significant mitigating effect on PA-induced β-cell damage. Mechanistically, PA increased ceramide content and c-Jun N-terminal kinase (JNK) phosphorylation. The ceramide synthase inhibitor effectively attenuated PA-induced β-cell damage and GPX4/Fe2+ abnormalities, while inhibiting JNK phosphorylation. Additionally, the JNK inhibitor SP600125 improved PA-induced cell damage. In conclusion, by promoting ceramide synthesis, PA inhibited GPX4 expression and increased intracellular Fe2+ to induce β-cell ferroptosis. Moreover, JNK may be a downstream mechanism of ceramide-triggered lipotoxic ferroptosis in β-cells.

Oral antidiabetic therapy versus early insulinization on glycemic control in newly diagnosed type 2 diabetes patients: a retrospective matched cohort study

Our study aims to compare the efficacy of oral antidiabetic therapy to early insulinization on glycemic control among newly diagnosed type 2 diabetes patients in real-world clinical practice. A retrospective cohort study conducted at a medical center in Taiwan analyzed 1256 eligible patients from January 2007 to December 2017. Propensity score matching resulted in well-balanced groups of 94 patients each in the oral antidiabetic drug (OAD) and early insulinization cohorts. Glycemic outcomes were assessed in both groups. Patients exclusively using OAD showed consistently lower glycated hemoglobin (HbA1c) levels at 3, 12, 24, and 36 months compared to insulin users. At later periods, 77.7% of OAD users achieved glycemic control versus 64.9% of insulin users, with a marginally significant difference. Subgroup analyses suggested a trend favoring well-controlled diabetes in the OAD group, though not statistically significant. Our study finds oral antidiabetic therapy is not inferior to early insulinization for glycemic control in newly diagnosed type 2 diabetes patients, irrespective of initial HbA1c levels. This supports oral therapy as a rational treatment option, even in cases with elevated HbA1c at diagnosis.

Insulin reduces endoplasmic reticulum stress-induced apoptosis by decreasing mitochondrial hyperpolarization and caspase-12 in INS-1 pancreatic β-cells

Pancreatic β-cell mass is a critical determinant of insulin secretion. Severe endoplasmic reticulum (ER) stress causes β-cell apoptosis; however, the mechanisms of progression and suppression are not yet fully understood. Here, we report that the autocrine/paracrine function of insulin reduces ER stress-induced β-cell apoptosis. Insulin reduced the ER-stress inducer tunicamycin- and thapsigargin-induced cell viability loss due to apoptosis in INS-1 β-cells. Moreover, the effect of insulin was greater than that of insulin-like growth factor-1 at physiologically relevant concentrations. Insulin did not attenuate the ER stress-induced increase in unfolded protein response genes. ER stress did not induce cytochrome c release from mitochondria. Mitochondrial hyperpolarization was induced by ER stress and prevented by insulin. The protonophore/mitochondrial oxidative phosphorylation uncoupler, but not the antioxidants N-acetylcysteine and α-tocopherol, exhibited potential cytoprotection during ER stress. Both procaspase-12 and cleaved caspase-12 levels increased under ER stress. The caspase-12 inhibitor Z-ATAD-FMK decreased ER stress-induced apoptosis. Caspase-12 overexpression reduced cell viability, which was diminished in the presence of insulin. Insulin decreased caspase-12 levels at the post-translational stages. These results demonstrate that insulin protects against ER stress-induced β-cell apoptosis in this cell line. Furthermore, mitochondrial hyperpolarization and increased caspase-12 levels are involved in ER stress-induced and insulin-suppressed β-cell apoptosis.

Global Trends and Frontier in Research on Pancreatic Alpha Cells: A Bibliometric Analysis from 2013 to 2023

PURPOSE

Over the past 20 years, much of the research on diabetes has focused on pancreatic beta cells. In the last 10 years, interest in the important role of pancreatic alpha cells in the pathogenesis of diabetes, which had previously received little attention, has grown. We aimed to summarize and visualize the hotspot and development trends of pancreatic alpha cells through bibliometric analysis and to provide research direction and future ideas for the treatment of diabetes and other islet-related diseases.

METHODS

We used two scientometric software packages (CiteSpace 6.1.R6 and VOSviewer1.6.18) to visualize the information and connection of countries, institutions, authors, and keywords in this field.

RESULTS

A total of 532 publications, published in 752 institutions in 46 countries and regions, were included in this analysis. The United States showed the highest output, accounting for 39.3% of the total number of published papers. The most active institution was Vanderbilt University, and the authors with highest productivity came from Ulster University. In recent years, research hotspots have concentrated on transdifferentiation, gene expression, and GLP-1 regulatory function. Visualization analysis shows that research hotspots mainly focus on clinical diseases as well as physiological and pathological mechanisms and related biochemical indicators.

CONCLUSIONS

This study provides a review and summary of the literature on pancreatic alpha cells through bibliometric and visual methods and shows research hotspot and development trends, which can guide future directions for research.

Protective effect of alizarin on vascular endothelial dysfunction via inhibiting the type 2 diabetes-induced synthesis of THBS1 and activating the AMPK signaling pathway

BACKGROUND

In this study, we investigated the protective effects of alizarin (AZ) on endothelial dysfunction (ED). AZ has inhibition of the type 2 diabetes mellitus (T2DM)-induced synthesis of thrombospondin 1 (THBS1). Adenosine 5'-monophosphate- activated protein kinase (AMPK), particularly AMPKα2 isoform, plays a critical role in maintaining cardiac homeostasis.

PURPOSE

The aim of this study was to investigate the ameliorative effect of AZ on vascular injury caused by T2DM and to reveal the potential mechanism of AZ in high glucose (HG)-stimulated human umbilical vein endothelial cells (HUVECs) and diabetic model rats.

STUDY DESIGN

HUVECs, rats and AMPK-/- transgenic mice were used to investigate the mitigating effects of AZ on vascular endothelial dysfunction caused by T2DM and its in vitro and in vivo molecular mechanisms.

METHODS

In type 2 diabetes mellitus rats and HUVECs, the inhibitory effect of alizarin on THBS1 synthesis was verified by immunohistochemistry (IHC), immunofluorescence (IF) and Western blot (WB) so that increase endothelial nitric oxide synthase (eNOS) content in vitro and in vivo. In addition, we verified protein interactions with immunoprecipitation (IP). To probe the mechanism, we also performed AMPKα2 transfection. AMPK's pivotal role in AZ-mediated prevention against T2DM-induced vascular endothelial dysfunction was tested using AMPKα2-/- mice.

RESULTS

We first demonstrated that THBS1 and AMPK are targets of AZ. In T2DM, THBS1 was robustly induced by high glucose and inhibited by AZ. Furthermore, AZ activates the AMPK signaling pathway, and recoupled eNOS in stressed endothelial cells which plays a protective role in vascular endothelial dysfunction.

CONCLUSIONS

The main finding of this study is that AZ can play a role in different pathways of vascular injury due to T2DM. Mechanistically, alizarin inhibits the increase in THBS1 protein synthesis after high glucose induction and activates AMPKα2, which increases NO release from eNOS, which is essential in the prevention of vascular endothelial dysfunction caused by T2DM.

Effects of Garlic on Glucose Parameters and Lipid Profile: A Systematic Review and Meta-Analysis on Randomized Controlled Trials

(1) Background: The effect of garlic on glucose and lipid metabolism in humans remains controversial. The aim of this study was to investigate the effects of garlic on blood lipid levels and glucose levels in humans through a systematic review and meta-analysis. (2) Methods: We extensively searched four databases, including PubMed, Web of Science, Embase, and the Cochrane Library, up to February 2024. To assess the collective impact of garlic and its supplements on fasting blood glucose (FBG), glycosylated hemoglobin (HbA1c), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG), an analysis was conducted using a random effects model. Subgroup analyses were performed when I2 < 50%. (3) Result: We found that the garlic intervention was effective in controlling FBG (mean difference = -7.01; 95% CI: -8.53, -5.49, p < 0.001), HbA1c (mean deviation = -0.66; 95% CI: -0.76, -0.55, p < 0.001, I2 = 62.9%), TC (mean difference = -14.17; 95% CI: -19.31, -9.03, p < 0.001), and LDL-C (mean difference = -8.20; 95% CI: -15.58, -0.81, p = 0.03); moreover, it also increased the level of HDL-C in humans (mean difference = 2.06; 95% CI: 1.54, 2.59; p < 0.001). Nonetheless, the intervention involving garlic did not yield a substantial impact on triglyceride (TG) levels. (4) Conclusion: The intervention of garlic is beneficial to control blood glucose and blood lipids in humans.

Insulin resistance, coronary artery lesion complexity and adverse cardiovascular outcomes in patients with acute coronary syndrome

BACKGROUND

Insulin resistance (IR) is linked to both the complexity of coronary artery lesions and the prognosis of acute coronary syndrome (ACS). However, the precise extent of this correlation and its impact on adverse cardiovascular outcomes in ACS patients remain unclear. Therefore, this study aims to investigate the intricate relationship between IR, coronary artery lesion complexity, and the prognosis of ACS through a cohort design analysis.

METHOD

A total of 986 patients with ACS who underwent percutaneous coronary intervention (PCI) were included in this analysis. IR was assessed using the triglyceride-glucose (TyG) index, while coronary artery lesion complexity was evaluated using the SYNTAX score. Pearson's correlation coefficients were utilized to analyze the correlations between variables. The association of the TyG index and SYNTAX score with major adverse cardiovascular events (MACEs) in ACS was investigated using the Kaplan-Meier method, restricted cubic splines (RCS), and adjusted Cox regression. Additionally, a novel 2-stage regression method for survival data was employed in mediation analysis to explore the mediating impact of the SYNTAX score on the association between the TyG index and adverse cardiovascular outcomes, including MACEs and unplanned revascularization.

RESULTS

During a median follow-up of 30.72 months, 167 cases of MACEs were documented, including 66 all-cause deaths (6.69%), 26 nonfatal myocardial infarctions (MIs) (2.64%), and 99 unplanned revascularizations (10.04%). The incidence of MACEs, all-cause death, and unplanned revascularization increased with elevated TyG index and SYNTAX score. Both the TyG index (non-linear, P = 0.119) and SYNTAX score (non-linear, P = 0.004) displayed a positive dose-response relationship with MACEs, as illustrated by the RCS curve. Following adjustment for multiple factors, both the TyG index and SYNTAX score emerged as significant predictors of MACEs across the total population and various subgroups. Mediation analysis indicated that the SYNTAX score mediated 25.03%, 18.00%, 14.93%, and 11.53% of the correlation between the TyG index and MACEs in different adjusted models, respectively. Similar mediating effects were observed when endpoint was defined as unplanned revascularization.

CONCLUSION

Elevated baseline TyG index and SYNTAX score were associated with a higher risk of MACEs in ACS. Furthermore, the SYNTAX score partially mediated the relationship between the TyG index and adverse cardiovascular outcomes.

Counterregulatory hormone and symptom responses to hypoglycaemia in people with type 1 diabetes, insulin-treated type 2 diabetes or without diabetes: the Hypo-RESOLVE hypoglycaemic clamp study

AIM

The sympathetic nervous and hormonal counterregulatory responses to hypoglycaemia differ between people with type 1 and type 2 diabetes and may change along the course of diabetes, but have not been directly compared. We aimed to compare counterregulatory hormone and symptom responses to hypoglycaemia between people with type 1 diabetes, insulin-treated type 2 diabetes and controls without diabetes, using a standardised hyperinsulinaemic-hypoglycaemic clamp.

MATERIALS

We included 47 people with type 1 diabetes, 15 with insulin-treated type 2 diabetes, and 32 controls without diabetes. Controls were matched according to age and sex to the people with type 1 diabetes or with type 2 diabetes. All participants underwent a hyperinsulinaemic-euglycaemic-(5.2 ± 0.4 mmol/L)-hypoglycaemic-(2.8 ± 0.13 mmol/L)-clamp.

RESULTS

The glucagon response was lower in people with type 1 diabetes (9.4 ± 0.8 pmol/L, 8.0 [7.0-10.0]) compared to type 2 diabetes (23.7 ± 3.7 pmol/L, 18.0 [12.0-28.0], p < 0.001) and controls (30.6 ± 4.7, 25.5 [17.8-35.8] pmol/L, p < 0.001). The adrenaline response was lower in type 1 diabetes (1.7 ± 0.2, 1.6 [1.3-5.2] nmol/L) compared to type 2 diabetes (3.4 ± 0.7, 2.6 [1.3-5.2] nmol/L, p = 0.001) and controls (2.7 ± 0.4, 2.8 [1.4-3.9] nmol/L, p = 0.012). Growth hormone was lower in people with type 2 diabetes than in type 1 diabetes, at baseline (3.4 ± 1.6 vs 7.7 ± 1.3 mU/L, p = 0.042) and during hypoglycaemia (24.7 ± 7.1 vs 62.4 ± 5.8 mU/L, p = 0.001). People with 1 diabetes had lower overall symptom responses than people with type 2 diabetes (45.3 ± 2.7 vs 58.7 ± 6.4, p = 0.018), driven by a lower neuroglycopenic score (27.4 ± 1.8 vs 36.7 ± 4.2, p = 0.012).

CONCLUSION

Acute counterregulatory hormone and symptom responses to experimental hypoglycaemia are lower in people with type 1 diabetes than in those with long-standing insulin-treated type 2 diabetes and controls.

Chemerin Levels in Individuals with Type 2 Diabetes and a Normal Weight versus Individuals with Type 2 Diabetes and Obesity: An Observational, Cross-Sectional Study

Chemerin acts as both a chemotactic agent and an adipokine that undergoes proteolytic cleavage, converting inactive precursors into their active forms before being subsequently inactivated. Elevated chemerin levels are linked to obesity and type 2 diabetes mellitus (T2D). This study aimed to elucidate the effects of T2D and obesity on chemerin levels by comparing plasma samples from individuals with a normal weight and T2D (BMI < 25; NWD group n = 22) with those from individuals who are overweight or obese and have T2D (BMI ≥ 25; OWD group n = 39). The total chemerin levels were similar in the NWD and OWD groups, suggesting that T2D may equalize the chemerin levels irrespective of obesity status. The cleavage of chemerin has been previously linked to myocardial infarction and stroke in NWD, with potential implications for inflammation and mortality. OWD plasma exhibited lower levels of cleaved chemerin than the NWD group, suggesting less inflammation in the OWD group. Here, we showed that the interaction between obesity and T2D leads to an equalization in the total chemerin levels. The cleaved chemerin levels and the associated inflammatory state, however, differ significantly, underscoring the complex relationship between chemerin, T2D, and obesity.

Molecular effects of Vitamin-D and PUFAs metabolism in skeletal muscle combating Type-II diabetes mellitus

Multiple post-receptor intracellular alterations such as impaired glucose transfer, glucose phosphorylation, decreased glucose oxidation, and glycogen production contribute to insulin resistance (IR) in skeletal muscle, manifested by diminished insulin-stimulated glucose uptake. Type-2 diabetes mellites (T2DM) has caused by IR, which is also seen in obese patients and those with metabolic syndrome. The Vitamin-D receptor (VDR) and poly unsaturated fatty acids (PUFAs) roles in skeletal muscle growth, shapes, and function for combating type-2 diabetes have been clarified throughout this research. VDR and PUFAs appears to show a variety of effects on skeletal muscle, in addition it shows a promising role on bone and mineral homeostasis. Individuals having T2DM are reported to suffer from severe muscular weakness and alterations in shape of the muscle. Several studies have investigated the effect on VDR on muscular strength and mass, which leads to Vitamin-D deficiency (VDD) in individuals, in which most commonly seen in elderly. VDR has been shown to affect skeletal cellular proliferation, intracellular calcium handling, as well as genomic activity in a variety of different ways such as muscle metabolism, insulin sensitivity, which is the major characteristic pathogenesis for IR in combating T2DM. The identified VDR gene polymorphisms are ApaI, TaqI, FokI, and BsmI that are associated with T2DM. This review collates informations on the mechanisms by which VDR activation takes place in skeletal muscles. Despite the significant breakthroughs made in recent decades, various studies show that IR affects VDR and PUFAs metabolism in skeletal muscle. Therefore, this review collates the data to show the role of VDR and PUFAs in the skeletal muscles to combat T2DM.

Skeletal muscle myostatin mRNA expression is upregulated in aged human adults with excess adiposity but is not associated with insulin resistance and ageing

Myostatin negatively regulates skeletal muscle growth and appears upregulated in human obesity and associated with insulin resistance. However, observations are confounded by ageing, and the mechanisms responsible are unknown. The aim of this study was to delineate between the effects of excess adiposity, insulin resistance and ageing on myostatin mRNA expression in human skeletal muscle and to investigate causative factors using in vitro models. An in vivo cross-sectional analysis of human skeletal muscle was undertaken to isolate effects of excess adiposity and ageing per se on myostatin expression. In vitro studies employed human primary myotubes to investigate the potential involvement of cross-talk between subcutaneous adipose tissue (SAT) and skeletal muscle, and lipid-induced insulin resistance. Skeletal muscle myostatin mRNA expression was greater in aged adults with excess adiposity than age-matched adults with normal adiposity (2.0-fold higher; P < 0.05) and occurred concurrently with altered expression of genes involved in the maintenance of muscle mass but did not differ between younger and aged adults with normal adiposity. Neither chronic exposure to obese SAT secretome nor acute elevation of fatty acid availability (which induced insulin resistance) replicated the obesity-mediated upregulation of myostatin mRNA expression in vitro. In conclusion, skeletal muscle myostatin mRNA expression is uniquely upregulated in aged adults with excess adiposity and insulin resistance but not by ageing alone. This does not appear to be mediated by the SAT secretome or by lipid-induced insulin resistance. Thus, factors intrinsic to skeletal muscle may be responsible for the obesity-mediated upregulation of myostatin, and future work to establish causality is required.

Modelling remission from overweight type 2 diabetes reveals how altering advice may counter relapse

The development or remission of diet-induced overweight type 2 diabetes involves many biological changes which occur over very different timescales. Remission, defined by HbA1c<6.5%, or fasting plasma glucose concentration G<126 mg/dl, may be achieved rapidly by following weight loss guidelines. However, remission is often short-term, followed by relapse. Mathematical modelling provides a way of investigating a typical situation, in which patients are advised to lose weight and then maintain fat mass, a slow variable. Remission followed by relapse, in a modelling sense, is equivalent to changing from a remission trajectory with steady state G<126 mg/dl, to a relapse trajectory with steady state G≥126 mg/dl. Modelling predicts that a trajectory which maintains weight will be a relapse trajectory, if the fat mass chosen is too high, the threshold being dependent on the lipid to carbohydrate ratio of the diet. Modelling takes into account the effects of hepatic and pancreatic lipid on hepatic insulin sensitivity and β-cell function, respectively. This study leads to the suggestion that type 2 diabetes remission guidelines be given in terms of model parameters, not variables; that is, the patient should adhere to a given nutrition and exercise plan, rather than achieve a certain subset of variable values. The model predicts that calorie restriction, not weight loss, initiates remission from type 2 diabetes; and that advice of the form 'adhere to the diet and exercise plan' rather than 'achieve a certain weight loss' may help counter relapse.

A systematic review of the association of Type I diabetes with sensorineural hearing loss

OBJECTIVES

Type 1 diabetes (T1D) has been associated with several comorbidities such as ocular, renal, and cardiovascular complications. However, the effect of T1D on the auditory system and sensorineural hearing loss (SNHL) is still not clear. The aim of this study was to conduct a systematic review to evaluate whether T1D is associated with hearing impairment.

METHODS

The databases PubMed, Science Direct, Scopus, and EMBASE were searched in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. Three reviewers independently screened, selected, and extracted data. The Joanna Briggs Institute (JBI) Critical Appraisal Tools for Analytical cross-sectional and case-control studies were used to perform quality assessment and risk of bias analysis on eligible studies.

RESULTS

After screening a total of 463 studies, 11 eligible original articles were included in the review to analyze the effects of T1D on the auditory system. The included studies comprised cross-sectional and case-control investigations. A total of 5,792 patients were evaluated across the 11 articles included. The majority of the studies showed that T1D was associated with hearing impairment compared to controls, including differences in PTAs and OAEs, increased mean hearing thresholds, altered acoustic reflex thresholds, and problems with the medial olivocochlear (MOC) reflex inhibitory effect. Significant risk factors included older age, increased disease duration, and higher HbA1C levels.

CONCLUSIONS

This systematic review suggests that there is a correlation between T1D and impairment on the auditory system. A multidisciplinary collaboration between endocrinologists, otolaryngologists, and audiologists will lead to early detection of hearing impairment in people with T1D resulting in early intervention and better clinical outcomes in pursuit of improving the quality of life of affected individuals.

REGISTRATION

This systematic review is registered in PROSPERO (CRD42023438576).

Environmental exposure to lead and cadmium are associated with triglyceride glucose index

The triglyceride glucose (TyG) index was suggested as a novel reliable surrogate marker for insulin resistance and related cardiovascular-metabolic diseases. We aimed to evaluate the association between the TyG index and environmental exposure to lead (Pb), mercury (Hg), and cadmium (Cd). A total of 9645 adults who enrolled in the Korea National Health and Nutrition Examination Survey in 2005, 2008-2013, and 2016 were included. Fasting plasma glucose and triglyceride levels were used to calculate the TyG index. Multivariate logistic regression model was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). We noted an increasing trend in the TyG index with increment of blood Pb and Cd concentrations. Participants in the highest quartile of blood Pb and Cd concentrations had higher TyG index values than those in the lowest quartile, with ORs (95% CIs) of 1.32 (1.07-1.63) and 1.29 (1.04-1.59) for Pb and Cd, respectively. Strong associations between blood Pb and Cd concentrations and the TyG index were found in men. Blood Hg concentrations did not show a significant association with the TyG index. Our study suggests that public health strategies for cardiovascular-metabolic disorder prevention should be directed toward individuals exposed to priority heavy metals.