Constant and intermittent high glucose enhances endothelial cell apoptosis through mitochondrial superoxide overproduction

Glycemic Variability as a Predictor of Graft Failure Following Infrainguinal Bypass for Peripheral Arterial Disease: A Retrospective Cohort Study

BACKGROUND

Glycemic variability (GV), measured as the change in visit-to-visit glycated hemoglobin (HbA1c), increases the risk of multiple adverse outcomes. However, the impact of GV on graft patency following infrainguinal bypass (IIB) is unknown. A retrospective cohort study was undertaken to assess the impact of GV on graft patency.

METHODS

A 3-year single-center retrospective case notes analysis of all people undergoing IIB between 2017 and 2019. Rutherford stage, graft conduit, level of bypass, procedure details, baseline demographics, comorbidities, and GV were assessed. Time to reintervention, ipsilateral amputation, or death was recorded to determine primary patency (PP).

RESULTS

One hundred six IIB outcomes were analyzed: mean (± standard deviation) age 68.0 (9.2) years; 69 (65.1%) male, 37 (33.9%), 75 (70.8%) had diabetes mellitus; and 46 (43.4%) underwent elective procedures. GV > 9.1% was associated with significantly lower median PP than GV < 9.1%, 198 (97-753.5) vs. 713 (166.5-1,044.5) days (P = 0.045). On univariate analysis, GV > 9.1% vs. < 9.1% was significantly associated with PP (hazard ratio [HR] 1.85 [confidence interval {CI} 1.091-3.136], P = 0.022). Bypass level was also a univariate predictor, with below knee bypasses (HR 2.31 [CI 1.164-4.564], P = 0.017), and tibial (HR 2.00 [CI 1.022-3.090], P < 0.043) having lower PP than above knee bypasses. On multivariate adjustment, GV > 9.1% and level of bypass remained independent predictors of PP, HR 1.96 (95% CI: 1.12-3.42, P = 0.018) and HR 2.54 (95% CI: 1.24-5.22, P = 0.011), respectively.

CONCLUSIONS

GV is an independent predictor of PP following infrainguinal bypass, thus optimizing GV should be a therapeutic target.

Topical delivery of insulin using novel organogel formulations: An approach for the management of diabetic wounds

Diabetes mellitus is a growing chronic form of diabetes, with lengthy health implications. It is predicted as poor diabetic wound recovery affects roughly 25% of all diabetes mellitus patients, frequently resulting in lower traumatic injury and severe external factors and emotional expenses. The insulin-resistant condition increases biofilm development, making diabetic wounds harder to treat. Nowadays, medical treatment and management of diabetic wounds, which have a significant amputation rate, a high-frequency rate, and a high death rate, have become a global concern. Topical formulations have played a significant part in diabetic wound management and have been developed to achieve a number of features. Because of its significant biocompatibility, moisture retention, and therapeutic qualities, topical insulin has emerged as an appealing and feasible wound healing process effector. With a greater comprehension of the etiology of diabetic wounds, numerous functionalized topical insulins have been described and shown good outcomes in recent years, which has improved some diabetic injuries. The healing of wounds is a physiological phenomenon that restores skin integrity and heals damaged tissues. Insulin, a powerful wound-healing factor, is also used in several experimental and clinical studies accelerate healing of diverse injuries.

Development of pro-angiogenic skin substitutes for wound healing

Wounds pose significant challenges to public health, primarily due to the loss of the mechanical integrity and barrier function of the skin and impaired angiogenesis, causing physical morbidities and psychological trauma to affect patients. Reconstructing the vasculature of the wound bed is crucial for promoting wound healing, reducing scar formation and enhancing the quality of life for patients. The development of pro-angiogenic skin substitutes has emerged as a promising strategy to facilitate vascularization and expedite the healing process of burn wounds. This review provides an overview of the various types of skin substitutes employed in wound healing, explicitly emphasising those designed to enhance angiogenesis. Synthetic scaffolds, biological matrices and tissue-engineered constructs incorporating stem cells and primary cells, cell-derived extracellular vesicles (EVs), pro-angiogenic growth factors and peptides, as well as gene therapy-based skin substitutes are thoroughly examined. The review summarises the existing challenges, future directions and potential innovations in pro-angiogenic dressing for skin substitutes. It highlights the need for continued research to develop new technologies and combine multiple strategies and factors, and to overcome obstacles and advance the field, ultimately leading to improved outcomes for wound patients.

Comparison of admission glycemic variability and glycosylated hemoglobin in predicting major adverse cardiac events among type 2 diabetes patients with heart failure following acute ST-segment elevation myocardial infarction

Background and Objectives

Hyperglycemia is associated with adverse outcomes in patients with acute myocardial infarction (AMI) as well as in patients with heart failure. However, the significance of admission glycemic variability (GV) in predicting outcomes among diabetes patients with heart failure (HF) following acute ST-segment elevation myocardial infarction (ASTEMI) remains unclear. This study aims to explore the prognostic value of admission GV and admission glycosylated hemoglobin (HbA1c) levels in individuals diagnosed with type 2 diabetes and HF following ASTEMI.

Methods

We measured GV and HbA1c upon admission in 484 consecutive patients diagnosed with type 2 diabetes and HF following ASTEMI. GV, indicated as the mean amplitude of glycemic excursions (MAGE), was assessed utilizing a continuous glucose monitoring system (CGMS). admission MAGE values were categorized as < 3.9 or ≥ 3.9 mmol/L, while HbA1c levels were classified as < 6.5 or ≥ 6.5%. Participants were followed up prospectively for 12 months. The relationship of admission MAGE and HbA1c to the major adverse cardiac event (MACE) of patients with type 2 diabetes and HF following ASTEMI was analyzed.

Results

Among the 484 enrolled patients, the occurrence of MACE differed significantly based on MAGE categories (< 3.9 vs. ≥ 3.9 mmol/L), with rates of 13.6% and 25.3%, respectively (P = 0.001). While MACE rates varied by HbA1c categories (< 6.5 vs. ≥ 6.5%) at 15.7% and 21.8%, respectively (P = 0.086). Patients with higher MAGE levels exhibited a notably elevated risk of cardiac mortality and an increased incidence of HF rehospitalization. The Kaplan-Meier curves analysis demonstrated a significantly lower event-free survival rate in the high MAGE level group compared to the low MAGE level group (log-rank test, P < 0.001), while HbA1c did not exhibit a similar distinction. In multivariate analysis, high MAGE level was significantly associated with incidence of MACE (hazard ratio 3.645, 95% CI 1.287-10.325, P = 0.015), whereas HbA1c did not demonstrate a comparable association (hazard ratio 1.075, 95% CI 0.907-1.274, P = 0.403).

Conclusions

Elevated admission GV emerges as a more significant predictor of 1-year MACE in patients with type 2 diabetes and HF following ASTEMI, surpassing the predictive value of HbA1c.

Correlation between time in range and serum uric acid in Chinese patients with type-2 diabetes: an observational cross-sectional study

BACKGROUND

At present, the relationship between serum uric acid and blood glucose is controversial, and even opposite conclusions have been reached. We aimed to investigate the relationship between time in range and serum uric acid and estimate the influence of serum uric acid on blood glucose fluctuations in Chinese patients with type-2 diabetes mellitus (T2DM).

METHODS

A total of 458 hospitalized patients with T2DM were selected. According to the SUA level, patients were divided into four groups by quartile: Q1 (≤ 254.5 µmol/L), Q2 (254.5-306.0 µmol/L), Q3 (306.0-385.5 µmol/L) and Q4 (> 385.5 µmol/L). The differences in general data, TIR and other clinical indicators between the four groups were assessed. Multifactor regression was used to analyze the relationship between subgroups of SUA and TIR, TBR, TAR, MAGE, SD, ADRR, MODD and M value. Curve fitting was used to analyze the association between TIR and SUA and to identify the inflection point.

RESULTS

TIR showed an overall increasing trend with increasing SUA, while HbA1c, TAR, MAGE, SD, ADRR, MODD and M value showed an overall decreasing trend with increasing SUA. Multivariate regression analysis showed that, compared with Q1, there was no correlation between SUA and TIR, TAR, ADRR, SD, or MODD in all models of Q2. In the Q3 and Q4 groups, SUA was correlated with SD, MODD, and MAGE in all models. In the Q4 group, SUA was correlated with TIR, TAR, ADRR, and the M value in all models. When SUA > 306 µmol/L (Q3 and Q4), TIR and SUA have a curve-like relationship, and the inflection point of the fitted curve was SUA = 460 mmol/L. Before the inflection point, β was 0.1, indicating that when SUA increases by 10 mmol/L, the corresponding TIR increases by 1%. After the inflection point, there was no significant difference in the correlation between TIR and SUA (P > 0.05).

CONCLUSIONS

There is a close relationship between TIR and SUA in T2DM patients, it is speculated that SUA in a certain range had a positive protective effect on blood glucose control.

Short-term glucose variability as a determinant of the healing rate of diabetic foot ulcer: A retrospective study

BACKGROUND

The aim of this study was to describe the clinical characteristics of people with diabetic foot ulcer (DFU) according to glucose variability (GV) and to investigate the relationship between GV and DFU outcome in a population with type 2 diabetes (T2D) and DFU.

METHODS

This is a retrospective study of 300 individuals aged 64.3 years (181 males) treated for DFU in a tertiary-care center with a regular follow-up for 6 months. Laboratory measurements and clinical assessments were collected at baseline. According to the coefficient of variation (CV) cut-off (≥36%), people were divided into two groups (low and high GV).

RESULTS

Compared with low GV group (n = 245), high GV group (n = 55) had significant longer duration of diabetes [low vs high GV, mean ± Standard Deviation (SD), 17.8 ± 11.8 vs 22.4 ± 10.8, P = 0.012], higher levels of glycated haemoglobin [median (IQR), 7.4 (6.6, 8.8) vs 8.2 (7.0, 9.6), P = 0.010] and urinary albumin excretion [25.2 (11.9, 77.0) vs 48.0 (23.2, 106.0), P = 0.031]. Moreover, 10 days self-monitoring of blood glucose-derived glycemic metrics were significantly different between groups. No differences among clinical features were found. The multiple logistic regression analysis identified CV and SD as negative predictors of healing.

CONCLUSIONS

In a population of people with T2D and DFU treated in a tertiary-care center, individuals with high GV had a 3-fold higher risk of healing failure, as compared with those with low GV. CV and SD were related to poor healing within 6 months follow-up.

Associations of variability in blood glucose and systolic blood pressure with mortality in patients with coronary artery disease: A retrospective cohort study from the MIMIC-IV database

AIMS

Variability of metabolic parameters, such as glycemic variability (GV) and systolic blood pressure variability (SBPV), are associated with adverse cardiovascular outcomes. However, whether these parameters have additive effects on mortality in patients with coronary artery disease (CAD) hospitalized in the intensive care unit (ICU) remains unclear.

METHODS

We retrospectively enrolled patients with CAD from the Medical Information Mart for Intensive Care-IV database. The highest tertile of variability was defined as high variability. A variability scoring system was established, which assigned 0 points to tertile 1, 1 point to tertile 2, and 2 points to tertile 3 for GV and SBPV.

RESULTS

Among 4237 patients with CAD, 400 patients died in hospital, and 967 patients died during 1-year follow-up. High GV and high SBPV were associated with an increased risk of mortality. The effects of GV and SBPV on in-hospital mortality were partially mediated by ventricular arrhythmias (18.0 % and 6.6 %, respectively). The risk of mortality gradually increased with the number of high-variability parameters and increasing variability scores.

CONCLUSIONS

GV and SBPV have additive effects on the risk of mortality in patients with CAD hospitalized in the ICU. Ventricular arrhythmias partially mediate the effects of GV and SBPV on in-hospital mortality.

Dietary (poly)phenols as modulators of the biophysical properties in endothelial cell membranes: its impact on nitric oxide bioavailability in hypertension

Hypertension is a major contributor to premature death, owing to the associated increased risk of damage to the heart, brain and kidneys. Although hypertension is manageable by medication and lifestyle changes, the risk increases with age. In an increasingly aged society, the incidence of hypertension is escalating, and is expected to increase the prevalence of (cerebro)vascular events and their associated mortality. Adherence to plant-based diets improves blood pressure and vascular markers in individuals with hypertension. Food flavonoids have an inhibitory effect towards angiotensin-converting enzyme (ACE1) and although this effect is greatly diminished upon metabolization, their microbial metabolites have been found to improve endothelial nitric oxide synthase (eNOS) activity. Considering the transmembrane location of ACE1 and eNOS, the ability of (poly)phenols to interact with membrane lipids modulate the cell membrane's biophysical properties and impact on nitric oxide (· NO) synthesis and bioavailability, remain poorly studied. Herein, we provide an overview of the current knowledge on the lipid remodeling of endothelial membranes with age, its impact on the cell membrane's biophysical properties and · NO permeability across the endothelial barrier. We also discuss the potential of (poly)phenols and other plant-based compounds as key players in hypertension management, and address the caveats and challenges in adopted methodologies.

Association between brain imaging biomarkers and continuous glucose monitoring-derived glycemic control indices in Japanese patients with type 2 diabetes mellitus

INTRODUCTION

Although type 2 diabetes mellitus (T2DM) is associated with alterations in brain structure, the relationship between glycemic control indices and brain imaging markers remains unclear. This study aimed to investigate the association between continuous glucose monitoring (CGM)-derived glycemic control indices and brain imaging biomarkers assessed by MRI.

RESEARCH DESIGN AND METHODS

This cross-sectional study included 150 patients with T2DM. The severity of cerebral white matter lesions (WMLs) was assessed using MRI for deep and subcortical white matter and periventricular hyperintensities. The degree of medial temporal lobe atrophy (MTA) was assessed using voxel-based morphometry. Each participant wore a retrospective CGM for 14 consecutive days, and glycemic control indices, such as time in range (TIR) and glycemia risk index (GRI), were calculated.

RESULTS

The proportion of patients with severe WMLs showed a decreasing trend with increasing TIR (P for trend=0.006). The proportion of patients with severe WMLs showed an increasing trend with worsening GRI (P for trend=0.011). In contrast, no significant association was observed between the degree of MTA and CGM-derived glycemic control indices, including TIR (P for trend=0.325) and GRI (P for trend=0.447).

CONCLUSIONS

The findings of this study indicate that the severity of WMLs is associated with TIR and GRI, which are indices of the quality of glycemic control.

TRIAL REGISTRATION NUMBER

UMIN000032143.

The research progress of crosstalk mechanism of autophagy and apoptosis in diabetic vascular endothelial injury

In recent years, the widespread prevalence of diabetes has become a major killer that threatens the health of people worldwide. Of particular concern is hyperglycemia-induced vascular endothelial injury, which is one of the factors that aggravate diabetic vascular disease. During the process of diabetic vascular endothelial injury, apoptosis is an important pathological manifestation and autophagy is a key regulatory mechanism. Autophagy and apoptosis interact with each other. Hence, the crosstalk mechanism between the two processes is an important means of regulating diabetic vascular endothelial injury. This article reviews the research progress in apoptosis in the context of diabetic vascular endothelial injury and discusses the crosstalk mechanism of autophagy and apoptosis and its role in this injury. The purpose is to guide the prevention and treatment of diabetic vascular endothelial injury in the future.

Effect of hydroalcoholic extract of Trigonella foenum-graecum leaves on wound healing in type 1 diabetic rats

Diabetes describes a group of metabolic disorders characterised by increased blood glucose concentration. People living with diabetes have a higher risk of morbidity and mortality than the general population. In 2015 it was estimated that there were 415 million (uncertainty interval: 340-536 million) people with diabetes aged 20-79 years, and 5.0 million deaths attributable to diabetes. When diabetic patients develop an ulcer, they become at high risk for major complications, including infection and amputation. The pathophysiologic relationship between diabetes and impaired healing is complex. Vascular, neuropathic, immune function, and biochemical abnormalities each contribute to the altered tissue repair. The use of herbal medicine has increased and attracted the attention of many researchers all over the world. In this study, we have evaluated the effect of 500mg/kg hydroalcoholic extract of Trigonella foenum-graecum leaves (TFG-E) on wound healing in diabetic rats using a full-thickness cutaneous incisional wound model. Wounds of treated animals showed better tensiometric indices, accelerated wound contraction, faster re-epithelialisation, improved neovascularisation, better modulation of fibroblasts and macrophage presence in the wound bed and moderate collagen formation.

Serum Cytokines and Growth Factors in Subjects with Type 1 Diabetes: Associations with Time in Ranges and Glucose Variability

The detrimental effect of hyperglycemia and glucose variability (GV) on target organs in diabetes can be implemented through a wide network of regulatory peptides. In this study, we assessed a broad panel of serum cytokines and growth factors in subjects with type 1 diabetes (T1D) and estimated associations between concentrations of these molecules with time in ranges (TIRs) and GV. One hundred and thirty subjects with T1D and twenty-seven individuals with normal glucose tolerance (control) were included. Serum levels of 44 cytokines and growth factors were measured using a multiplex bead array assay. TIRs and GV parameters were derived from continuous glucose monitoring. Subjects with T1D compared to control demonstrated an increase in concentrations of IL-1β, IL-1Ra, IL-2Rα, IL-3, IL-6, IL-7, IL-12 p40, IL-16, IL-17A, LIF, M-CSF, IFN-α2, IFN-γ, MCP-1, MCP-3, and TNF-α. Patients with TIR ≤ 70% had higher levels of IL-1α, IL-1β, IL-6, IL-12 p70, IL-16, LIF, M-CSF, MCP-1, MCP-3, RANTES, TNF-α, TNF-β, and b-NGF, and lower levels of IL-1α, IL-4, IL-10, GM-CSF, and MIF than those with TIR > 70%. Serum IL-1β, IL-10, IL-12 p70, MCP-1, MCP-3, RANTES, SCF, and TNF-α correlated with TIR and time above range. IL-1β, IL-8, IL-10, IL-12 p70, MCP-1, RANTES, MIF, and SDF-1α were related to at least one amplitude-dependent GV metric. In logistic regression models, IL-1β, IL-4, IL-10, IL-12 p70, GM-CSF, HGF, MCP-3, and TNF-α were associated with TIR ≤ 70%, and MIF and PDGF-BB demonstrated associations with coefficient of variation values ≥ 36%. These results provide further insight into the pathophysiological effects of hyperglycemia and GV in people with diabetes.

Pharmacological potentials of lycopene against aging and aging-related disorders: A review

Aging and aging-related chronic disorders are one of the principal causes of death worldwide. The prevalence of these disorders is increasing gradually and globally. Considering this unwavering acceleration of the global burden, seeking alternatives to traditional medication to prevent the risk of aging disorders is needed. Among them, lycopene, a carotenoid, is abundant in many fruits and vegetables, including tomatoes, grapefruits, and watermelons, and it has a unique chemical structure to be a potent antioxidant compound. This nutraceutical also possesses several anti-aging actions, including combating aging biomarkers and ameliorating several chronic disorders. However, no systematic evaluation has yet been carried out that can comprehensively elucidate the effectiveness of lycopene in halting the course of aging and the emergence of chronic diseases linked to aging. This review, therefore, incorporates previous pre-clinical, clinical, and epidemiological studies on lycopene to understand its potency in treating aging disorders and its role as a mimic of caloric restriction. Lycopene-rich foods are found to prevent or attenuate aging disorders in various research. Based on the evidence, this review suggests the clinical application of lycopene to improve human health and alleviate the prevalence of aging and aging disorders.

Pre-stroke glycemic variability estimated by glycated albumin predicts hematoma expansion and poor outcomes in patients with spontaneous intracerebral hemorrhage

Glycemic variability has been shown to be correlated more with oxidative stress than chronic hyperglycemia. We evaluated the impact of pre-stroke glycemic variability measured using glycated albumin (GA) on hematoma expansion and clinical outcomes following spontaneous intracerebral hemorrhage (ICH). We consecutively enrolled 343 patients with ICH for 72 months using a single-center registry database. The primary outcome measure was hematoma expansion. The secondary outcome measures were early neurological deterioration (END), 1-month mortality, and 3-month poor functional outcomes (modified Rankin scale score of 4-6). The patients were divided into two groups based on pre-stroke glycemic variability: a higher GA group (GA ≥ 16.0%) and a lower GA group (GA < 16.0%). During the study period, there were 63 (18.4%) events of hematoma expansion, 61 (17.8%) of END, 45 (13.1%) of 1-month mortality, and 45 (13.1%) of 3-month poor functional outcomes after ICH. The higher GA group (36.4%) had higher rates of hematoma expansion, END, 1-month mortality, and 3-month poor functional outcomes than the lower GA group. Multivariate analysis showed that a higher GA level was significantly associated with increased hematoma expansion (adjusted odds ratio 5.83; 95% confidence interval [CI] 2.58-13.19, p < 0.001). The area under the receiver operating characteristic curve of GA (0.83; 95% CI 0.48-0.65) for predicting hematoma expansion was higher than that of glycated hemoglobin (0.57; 95% CI 0.48-0.65, p for DeLong's pairwise comparison < 0.001). Higher GA levels could be a reliable marker for predicting hematoma expansion and poor outcomes following ICH.

Association of fasting blood glucose variability with all-cause mortality in heart transplant recipients

BACKGROUND

Fasting blood glucose (FBG) variability, an emerging marker of glycemic control, has been shown to be related to the risk of cardiovascular events and all-cause mortality in subjects with or without diabetes. However, whether FBG variability is independently associated with a higher all-cause mortality in heart transplant recipients remains unknown.

METHODS

We performed a retrospective cohort study including 373 adult recipients who survived for at least 1 year after heart transplantation with a functioning graft and measured FBG more than three times within first year after transplantation. Multivariable adjusted Cox regression analyses were performed to assess the association between FBG variability and all-cause mortality.

RESULTS

Patients were categorized into three groups according to the coefficient of variation of FBG level: ≤7.0%, 7.0%-13.5%, and >13.5%. During a median follow-up of 44.4 months (interquartile range [IQR], 22.6-63.3 months), 31 (8.3%) participants died. In univariate analyses, FBG variability was associated with an increased all-cause mortality (hazard ratio [HR]: 3.00, 95% confidence interval [CI]: 1.67, 5.38; p < .001). This association remained materially unchanged in the multivariable model adjusted for components of demographics, cardiovascular history and lifestyle, hospital information, immunosuppressive therapy, and post-transplant renal function (HR: 2.75, 95% CI: 1.43, 5.28; p = .004).

CONCLUSIONS

After heart transplantation, high FBG variability is strongly and independently associated with an increased risk of all-cause mortality. Our findings suggest that FBG variability is a novel risk factor and prognostic marker for heart transplantation recipients in outpatient clinic.

Exendin-4 protects against high glucose-induced mitochondrial dysfunction and oxidative stress in SH-SY5Y neuroblastoma cells through GLP-1 receptor/Epac/Akt signaling

Mitochondrial dysfunction under diabetic condition leads to the development and progression of neurodegenerative complications. Recently, the beneficial effects of glucagon-like peptide-1 (GLP-1) receptor agonists on diabetic neuropathies have been widely recognized. However, molecular mechanisms underlying the neuroprotective effects of GLP-1 receptor agonists against high glucose (HG)-induced neuronal damages is not completely elucidated. Here, we investigated the underlying mechanisms of GLP-1 receptor agonist treatment against oxidative stress, mitochondrial dysfunction, and neuronal damages under HG-conditions mimicking a diabetic hyperglycemic state in SH-SY5Y neuroblastoma cells. We revealed that treatment with exendin-4, a GLP-1 receptor agonist, not only increased the expression of survival markers, phospho-Akt/Akt and Bcl-2, but also decreased the expression of pro-apoptotic marker, Bax, and reduced the levels of reactive oxygen species (ROS) defense markers (catalase, SOD-2, and HO-1) under HG conditions. The expressions of mitochondrial function associated genes, MCU and UCP3, and mitochondrial fission genes, DRP1 and FIS1, were decreased by exendin-4 compared to non-treated levels, while the protein expression levels of mitochondrial homeostasis regulators, Parkin and PINK1, were enhanced. In addition, blockade of Epac and Akt activities was able to antagonize these neuroprotective effects of exendin-4. Collectively, we demonstrated that stimulation of GLP-1 receptor propagates a neuroprotective cascade against the oxidative stresses and mitochondrial dysfunctions as well as augments survival through the Epac/Akt-dependent pathway. Therefore, the revealed mechanisms underlying GLP-1 receptor pathway by preserving mitochondrial homeostasis would be a therapeutic candidate to alleviate neuronal dysfunctions and delay the progression of diabetic neuropathies.

Preoperative carbohydrate load to reduce perioperative glycemic variability and improve surgical outcomes: A scoping review

The detrimental effects of both diabetes mellitus (DM) and hyperglycemia in the perioperative period are well established and have driven extensive efforts to control blood glucose concentration (BGC) in a variety of clinical settings. It is now appreciated that acute BGC spikes, hypoglycemia, and high glycemic variability (GV) lead to more endothelial dysfunction and oxidative stress than uncomplicated, chronically elevated BGC. In the perioperative setting, fasting is the primary approach to reducing the risk for pulmonary aspiration; however, prolonged fasting drives the body into a catabolic state and therefore may increase GV. Elevated GV in the perioperative period is associated with an increased risk for postoperative complications, including morbidity and mortality. These challenges pose a conundrum for the management of patients typically instructed to fast for at least 8 h before surgery. Preliminary evidence suggests that the administration of an oral preoperative carbohydrate load (PCL) to stimulate endogenous insulin production and reduce GV in the perioperative period may attenuate BGC spikes and ultimately decrease postoperative morbidity, without significantly increasing the risk of pulmonary aspiration. The aim of this scoping review is to summarize the available evidence on the impact of PCL on perioperative GV and surgical outcomes, with an emphasis on evidence pertaining to patients with DM. The clinical relevance of GV will be summarized, the relationship between GV and postoperative course will be explored, and the impact of PCL on GV and surgical outcomes will be presented. A total of 13 articles, presented in three sections, were chosen for inclusion. This scoping review concludes that the benefits of a PCL outweigh the risks in most patients, even in those with well controlled type 2 DM. The administration of a PCL might effectively minimize metabolic derangements such as GV and ultimately result in reduced postoperative morbidity and mortality, but this remains to be proven. Future efforts to standardize the content and timing of a PCL are needed. Ultimately, a rigorous data-driven consensus opinion regarding PCL administration that identifies optimal carbohydrate content, volume, and timing of ingestion should be established.

Proteomics and transcriptomics explore the effect of mixture of herbal extract on diabetic wound healing process

BACKGROUND

The annual incidence of diabetic foot ulcers (DFUs) has been reported to vary from 0.2% to 11% in diabetes-specific clinical settings and less than 0.1% to 8% in community- and population-based cohorts. According to the International Diabetes Foundation, approximately 40 million to 60 million people worldwide are affected by DFUs, and a recent meta-analysis indicates a global prevalence of 6.3% among adults with diabetes, or about 33 million individuals. The cost of diabetes care is significant, amounting to $273 billion in direct and $90 billion in indirect expenses annually, in America. Foot complications in diabetes care excess annual expenditures ranging from 50% to 200% above the baseline cost of diabetes-related care. The cost of advanced-stage ulcers can be more than $50,000 per wound episode, and the direct expenses of major amputation are even higher. DFUs can be treated using various methods, including wound dressings, antibiotics, pressure-off loading, skin substitutes, stem cells, debridement, topical oxygen therapy, gene therapy and growth factors. For severe DFUs patients are at risk of amputation if treatment is not timely or appropriate. Amputating limbs not only causes physical pain to patients, but also brings economic burden due to lost productivity, and decreased employment linked to DFUs. Currently, long-term use of local antibiotics in clinical practice is prone to induce drug resistance, while growth factors do not effectively inhibit bacterial growth and control inflammation in wounds. Stem cell and gene therapies are still in the experimental stage. The method of local debridement combined with negative pressure therapy is expensive. Therefore, we urgently need an affordable, non-surgical method to treat diabetic ulcers. Extracts of bark of Bauhinia purpurea, Paeoniae rubrae, Angelica dahurica (Hoffm.) Benth. & Hook.f. ex Franch. & Sav. (Hoffm.) Benth. & Hook.f. ex Franch. & Sav., Acorus calamus L, and Radix Angelicae biseratae have been used as traditional remedies to treat inflammation-related diseases and cutaneous wounds due to their anti-inflammatory properties and their ability to promote vascular renewal. However, there have been few studies on the mixture of these five herbal extracts on diabetic wound healing.

PURPOSE

This study was designed to assess the healing effect of a mixture of five aforementioned herbal extracts on diabetic ulcer wounds in rats, and to reveal the potential mechanisms behind any potential wound healing using transcriptomics and proteomics.

STUDY DESIGN

We designed the experiment to explore the effects of five herbal extracts on diabetic wound healing process through in vivo experiments and to investigate the underlying mechanisms through proteomics and transcriptomics.

METHODS

We used a mixture of five aforementioned herbal extract to treat rat model of diabetic established by intraperitoneal injection of streptozotocin, and a 2 × 2 cm round full-thickness skin defect was created on the back of the rat. Staphylococcus aureus (1 ml of 1.5 × 10⁹ cfu/ml) was evenly applied to the wound. The wound was then observed for 72 h. The infected ulcer model of diabetic rats was considered to be successfully established if the wound was found to be infected with S. aureus. According to different medications, the rats were divided into three groups, namely mixture of herbal extract (MHE), Kangfuxin solution (KFS) and control (Ctrl). The effects of the medicine on wound healing were observed. HE staining and Masson staining were performed to evaluate the histopathological changes and collagen synthesis. IHC staining was used to assess the neovascularization, and M2 macrophage proliferation was determined by immunofluorescence staining. Proteomic and transcriptomic studies were performed to explore potential mechanism of five herbal extracts to promote wound healing. UHPLC-QE-MS was performed to identify the chemical composition of mixture of herbal extract.

RESULTS

The study show that the mixed herbal extract promotes angiogenesis, proliferation of M2 macrophages, and collagen synthesis. Transcriptomics showed that rno-miR-1298, rno-miR-144-5p, and rno-miR-92a-1-5p are vital miRNAs which also play a significant role in role in regulating wound healing. Proteomics results showed that the following proteins were important in wounds treated with MHE: Rack1, LOC100362366, Cops2, Cops6, Eif4e, Eif3c, Rpl12, Srp54, Rpl13 and Lsm7. Autophagy, PI3-Akt and mTOR signaling pathways were enriched after treatment with MHE compared to other groups.

CONCLUSION

Herein, we have shown that MHE containing extracts of bark of Bauhinia purpurea, P. rubrae, A. dahurica (Hoffm.) Benth. & Hook.f. ex Franch. & Sav., A. calamus L, and R. A. biseratae has significant wound healing effects in the diabetic ulcer wound rat model. These results suggest that local application of MHE in diabetic wounds can accelerate the wound healing process. Moreover, in vivo experiments revealed that the diabetic wound healing process was primarily mediated by angiogenesis and M2 macrophage transition. Therefore, this study may provide a promising and non-surgical therapeutic strategy to accelerate diabetic wound healing, thereby decreasing the number of limb amputations in diabetic patients.

Oscillating Glucose Induces the Increase in Inflammatory Stress through Ninjurin-1 Up-Regulation and Stimulation of Transport Proteins in Human Endothelial Cells

Clinical data implicate fluctuations of high levels of plasma glucose in cardiovascular diseases. Endothelial cells (EC) are the first cells of the vessel wall exposed to them. Our aim was to evaluate the effects of oscillating glucose (OG) on EC function and to decipher new molecular mechanisms involved. Cultured human ECs (EA.hy926 line and primary cells) were exposed to OG (5/25 mM alternatively at 3 h), constant HG (25 mM) or physiological concentration (5 mM, NG) for 72 h. Markers of inflammation (Ninj-1, MCP-1, RAGE, TNFR1, NF-kB, and p38 MAPK), oxidative stress (ROS, VPO1, and HO-1), and transendothelial transport proteins (SR-BI, caveolin-1, and VAMP-3) were assessed. Inhibitors of ROS (NAC), NF-kB (Bay 11-7085), and Ninj-1 silencing were used to identify the mechanisms of OG-induced EC dysfunction. The results revealed that OG determined an increased expression of Ninj-1, MCP-1, RAGE, TNFR1, SR-B1, and VAMP-3 andstimulated monocyte adhesion. All of these effects were induced bymechanisms involving ROS production or NF-kB activation. NINJ-1 silencing inhibited the upregulation of caveolin-1 and VAMP-3 induced by OG in EC. In conclusion, OG induces increased inflammatory stress, ROS production, and NF-kB activation and stimulates transendothelial transport. To this end, we propose a novel mechanism linking Ninj-1 up-regulation to increased expression of transendothelial transport proteins.

Roxadustat, a HIF-PHD inhibitor with exploitable potential on diabetes-related complications

Diabetes mellitus (DM) is a group of metabolic diseases caused by absolute or relative deficiency of insulin secretion and characterized by chronic hyperglycemia. Its complications affect almost every tissue of the body, usually leading to blindness, renal failure, amputation, etc. and in the final stage, it mostly develops into cardiac failure, which is the main reason why diabetes mellitus manifests itself as a high clinical lethality. The pathogenesis of diabetes mellitus and its complications involves various pathological processes including excessive production of mitochondrial reactive oxygen species (ROS) and metabolic imbalance. Hypoxia-inducible Factor (HIF) signaling pathway plays an important role in both of the above processes. Roxadustat is an activator of Hypoxia-inducible Factor-1α, which increases the transcriptional activity of Hypoxia-inducible Factor-1α by inhibiting hypoxia-inducible factor prolyl hydroxylase (HIF-PHD). Roxadustat showed regulatory effects on maintaining metabolic stability in the hypoxic state of the body by activating many downstream signaling pathways such as vascular endothelial growth factor (VEGF), glucose transporter protein-1 (GLUT1), lactate dehydrogenase (LDHA), etc. This review summarizes the current research findings of roxadustat on the diseases of cardiomyopathy, nephropathy, retinal damage and impaired wound healing, which also occur at different stages of diabetes and greatly contribute to the damage caused by diabetes to the organism. We attempts to uncover a more comprehensive picture of the therapeutic effects of roxadustat, and inform its expanding research about diabetic complications treatment.

Long-Term Visit-to-Visit Glycemic Variability as a Predictor of Major Adverse Limb and Cardiovascular Events in Patients With Diabetes

Background Peripheral arterial disease (PAD) is a severe complication in patients with type 2 diabetes. Glycemic variability (GV) is associated with increased risks of developing microvascular and macrovascular diseases. However, few studies have focused on the association between GV and PAD. Methods and Results This cohort study used a database maintained by the National Taiwan University Hospital, a tertiary medical center in Taiwan. For each individual, GV parameters were calculated, including fasting glucose coefficient of variability (FGCV) and hemoglobin A1c variability score (HVS). Multivariate Cox regression models were constructed to estimate the relationships between GV parameters and composite scores for major adverse limb events (MALEs) and major adverse cardiovascular events (MACEs). Between 2014 and 2019, a total of 45 436 adult patients with prevalent type 2 diabetes were enrolled for analysis, and GV was assessed during a median follow-up of 64.4 months. The average number of visits and time periods were 13.38 and 157.87 days for the HVS group and 14.27 and 146.59 days for the FGCV group, respectively. The incidence rates for cardiac mortality, PAD, and critical limb ischemia (CLI) were 5.38, 20.11, and 2.41 per 1000 person-years in the FGCV group and 5.35, 20.32, and 2.50 per 1000 person-years in HVS group, respectively. In the Cox regression model with full adjustment, the highest FGCV quartile was associated with significantly increased risks of MALEs (hazard ratio [HR], 1.57 [95% CI, 1.40-1.76]; P<0.001) and MACEs (HR, 1.40 [95% CI, 1.25-1.56]; P<0.001). Similarly, the highest HVS quartile was associated with significantly increased risks of MALEs (HR, 1.44 [95% CI, 1.28-1.62]; P<0.001) and MACEs (HR, 1.28 [95% CI, 1.14-1.43]; P<0.001). The highest FGCV and HVS quartiles were both associated with the development of PAD and CLI (FGCV: PAD [HR, 1.57; P<0.001], CLI [HR, 2.19; P<0.001]; HVS: PAD [HR, 1.44; P<0.001], CLI [HR, 1.67; P=0.003]). The Kaplan-Meier analysis showed significantly higher risks of MALEs and MACEs with increasing GV magnitude (log-rank P<0.001). Conclusions Among individuals with diabetes, increased GV is independently associated with the development of MALEs, including PAD and CLI, and MACEs. The benefit of maintaining stable glycemic levels for improving clinical outcomes warrants further studies.

Effects of microRNAs on angiogenesis in diabetic wounds

Diabetes mellitus is a morbid condition affecting a growing number of the world population, and approximately one third of diabetic patients are afflicted with diabetic foot ulcers (DFU), which are chronic non-healing wounds that frequently progress to require amputation. The treatments currently used for DFU focus on reducing pressure on the wound, staving off infection, and maintaining a moist environment, but the impaired wound healing that occurs in diabetes is a constant obstacle that must be faced. Aberrant angiogenesis is a major contributor to poor wound healing in diabetes and surgical intervention is often necessary to establish peripheral blood flow necessary for healing wounds. Over recent years, microRNAs (miRNAs) have been implicated in the dysregulation of angiogenesis in multiple pathologies including diabetes. This review explores the pathways of angiogenesis that become dysregulated in diabetes, focusing on miRNAs that have been identified and the mechanisms by which they affect angiogenesis.

Elevation of hemoglobin A1c increases the risk of decline in left ventricular systolic function among patients with coronary artery disease

AIMS

The aim of this study was to investigate the association of HbA1c and left ventricular (LV) systolic function among patients with coronary artery disease (CAD).

METHODS

CAD patients from the Cardiorenal ImprovemeNt II (CIN-II, NCT05050877) registry were included in the study. They were separated into four groups based on HbA1c levels (Q1: HbA1c<5.7%; Q2: 5.7% ≤ HbA1c < 6.1%; Q3: 6.1% ≤ HbA1c < 6.9%; Q4: HbA1c ≥ 6.9%). The endpoint was decline in LV systolic function, defined as an absolute decrease in LV ejection fraction (LVEF) ≥10% from baseline to follow-up with 3-12 months. The association of HbA1c and LVEF was assessed by logistics regression models.

RESULTS

CAD patients (n = 3,994) (age 62.9 ± 10.6 years; 22.2% female) were included in the final analysis. A decline in LV systolic function was recorded in 429 (11%) patients during follow-up. After fully adjusting for confounders, HbA1c was significantly associated with the high risk of decline in LV systolic function (OR 1.12 [95%CI 1.05-1.20] P = 0.001). By stratifying HbA1c as four groups, there is a significantly increased risk of decline in LV systolic function when HbA1c ≥6.1% (Q2, Q3 and Q4 vs Q1, with OR 1.22 [0.88-1.68] P = 0.235; OR 1.48 [1.07-2.05] P = 0.019; OR 1.60 [1.160-2.22] P = 0.004, respectively). Meanwhile, patients with decline in LV systolic function had a higher risk of cardiovascular death.

CONCLUSIONS

Elevated HbA1c is a predictor of decline in LV systolic function in CAD patients. Clinicians should be aware of the risk of decline in LV systolic function in CAD patients with elevated HbA1c, and take measures as soon as possible.

In Vitro Modeling of Diabetes Impact on Vascular Endothelium: Are Essentials Engaged to Tune Metabolism?

Angiopathy is a common complication of diabetes mellitus. Vascular endothelium is among the first targets to experience blood-borne metabolic alterations, such as hyperglycemia and hyperlipidemia, the hallmarks of type 2 diabetes. To explore mechanisms of vascular dysfunction and eventual damage brought by these pathologic conditions and to find ways to protect vasculature in diabetic patients, various research approaches are used including in vitro endothelial cell-based models. We present an analysis of the data available from these models that identifies early endothelial cell apoptosis associated with oxidative stress as the major outcome of mimicking hyperglycemia and hyperlipidemia in vitro. However, the fate of endothelial cells observed in these studies does not closely follow it in vivo where massive endothelial damage occurs mainly in the terminal stages of diabetes and in conjunction with comorbidities. We propose that the discrepancy is likely in missing essentials that should be available to cultured endothelial cells to adjust the metabolic state and withstand the immediate apoptosis. We discuss the role of carnitine, creatine, and AMP-activated protein kinase (AMPK) in suiting the endothelial metabolism for long-term function in diabetic type milieu in vitro. Engagement of these essentials is anticipated to expand diabetes research options when using endothelial cell-based models.

Pro-tumorigenic role of type 2 diabetes-induced cellular senescence in colorectal cancer

Colorectal cancer (CRC) is the second leading cause of cancer-related mortality worldwide. The disease still remains incurable and highly lethal in the advanced stage, representing a global health concern. Therefore, it is essential to understand the causes and risk factors leading to its development. Because age-related cellular senescence and type 2 diabetes (T2D) have been recognised as risk factors for CRC development, the recent finding that type 2 diabetic patients present an elevated circulating volume of senescent cells raises the question whether type 2 diabetes facilitates the process of CRC tumorigenesis by inducing premature cell senescence. In this review, we will discuss the mechanisms according to which T2D induces cellular senescence and the role of type 2 diabetes-induced cellular senescence in the pathogenesis and progression of colorectal cancer. Lastly, we will explore the current therapeutic approaches and challenges in targeting senescence.

Biopolymeric composite hydrogel loaded with silver NPs and epigallocatechin gallate (EGCG) effectively manages ROS for rapid wound healing in type II diabetic wounds

Delayed wound healing in patients having type-II diabetes mellitus (T2DM) often results in a high rate of amputation. We report an innovative Guar Gum-based macroporous hydrogel (HG) infused with an antibacterial agent (Ag NPs), and antioxidant, epigallocatechin gallate (EGCG) to address rapid wound healing and interestingly could inhibit the associated pathophysical bone infection in a high-fat-diet-induced T2DM C57BL/6 mice model. The HG-Ag-EGCG elicits scar-free wound healing in subcutaneous wounds and histopathological evidence confirmed HG-Ag-EGCG hydrogel patch elicits better wound healing through enhanced cell proliferation, mature connecting tissue fiber formation, minimum void spaces formation, and better re-epithelialization when compared with a market available hydrogel patch material (Luofucon®). Supportive of the in vivo outcomes, in vitro experiments delineated better-wound closure due to improved management of ROS by the HG-Ag-EGCG. Additionally, a favorable non-toxicity outcome assessed through both in vitro and in vivo conditions confirmed its potential applicability in clinical wound care management.

Blood Glucose Fluctuation in Older Adults with Diabetes Mellitus and End-Stage Renal Disease on Maintenance Hemodialysis: An Observational Study

INTRODUCTION

Patients with diabetes mellitus and end-stage renal disease are at a high risk of developing coronary, cerebrovascular, and peripheral vascular diseases. This study aimed to characterize hypoglycemia and blood glucose fluctuations associated with maintenance hemodialysis in older adult patients with diabetes mellitus and end-stage renal disease using a continuous glucose monitoring system.

METHODS

Seven patients were enrolled in this study, and 13 pairs of continuous glucose monitoring system data were collected. Each pair included data of 1 dialysis-on day and 1 dialysis-off day. Information on basic patient characteristics, including age, diabetes mellitus duration, hemodialysis duration, and proportions of hemoglobin A1c and glycated albumin, were collected. Differences in blood glucose fluctuation were compared between dialysis-on days and dialysis-off days.

RESULTS

The mean blood glucose on dialysis-on days (6.96 ± 2.57 mmol/L) was significantly lower than that on dialysis-off days (7.68 ± 2.31 mmol/L; P < 0.05). In contrast, the following parameters had significantly higher values (all P < 0.05) on dialysis-on days compared to dialysis-off days: large amplitude of glycemic excursion level (5.82 ± 2.86 mmol/L versus 4.21 ± 1.71 mmol/L), large amplitude of glycemic excursion level from 8 a.m. to 2 p.m. (3.6 ± 1.74 mmol/L versus 2.8 ± 1.33 mmol/L), mean amplitude of glycemic excursion level (4.78 ± 1.68 mmol/L versus 3.89 ± 1.67 mmol/L), mean amplitude of glycemic excursion level from 8 a.m. to 2 p.m. (4.01 ± 1.03 mmol/L versus 3.12. ± 0.97 mmol/L), standard deviation of blood glucose (1.55 ± 0.89 mmol/L versus 1.03 ± 0.4 mmol/L), and time below a target glucose range of less than 3.9 mmol/L (8.27% versus 4.25%).

CONCLUSION

Fluctuations in blood glucose levels were larger on dialysis-on days, particularly from the start of hemodialysis to 2 h post-hemodialysis, than on dialysis-off days. Hypoglycemia, as indicated by the time below a target glucose range of less than 3.9 mmol/L, occurred more frequently on dialysis-on days than on dialysis-off days.

Relevance of NLRP3 Inflammasome-Related Pathways in the Pathology of Diabetic Wound Healing and Possible Therapeutic Targets

Wound healing is a major secondary complication in type 2 diabetes, which results in significant disability and mortality, imposing a significant clinical and social burden. Sustained activation of the Nod-like receptor protein (NLRP) inflammasome in wounds is responsible for excessive inflammatory responses and aggravates wound damage. The activation of the NLRP3 inflammasome is regulated by a two-step process: the priming/licensing (signal 1) step involved in transcription and posttranslation and the protein complex assembly (signal 2) step triggered by danger molecules. This review focuses on the advances made in understanding the pathophysiological mechanisms underlying wound healing in the diabetic microenvironment. Simultaneously, this review summarizes the molecular mechanisms of the main regulatory pathways associated with signal 1 and signal 2, which trigger the NLRP3 inflammasome complex assembly in the development of diabetic wounds (DW). Activation of the NLRP3 inflammasome-related pathway, involving the disturbance in Nrf2 and the NF-κB/NLRP3 inflammasome, TLR receptor-mediated activation of the NF-κB/NLRP3 inflammasome, and various stimuli inducing NLRP3 inflammasome assembly play a pivotal role in DW healing. Furthermore, therapeutics targeting the NLRP3 inflammasome-related pathways may promote angiogenesis, reprogram immune cells, and improve DW healing.

The Effect of High and Variable Glucose on the Viability of Endothelial Cells Co-Cultured with Smooth Muscle Cells

Diabetes mellitus causes endothelial dysfunction. The aim of this study was to investigate the effect of normal (5 mmol/L), high (20 mmol/L), and fluctuating (5 and 20 mmol/L changed every day) glucose concentration in the culture medium on the viability of human umbilical vein endothelial cells (HUVECs) co-cultured with human umbilical artery smooth muscle cells (HUASMCs). The cultures were conducted on semi-permeable flat polysulfone (PSU) fibronectin-coated membranes immobilized in self-made inserts. The insert contained either HUVECs on a single membrane or HUASMCs and HUVECs on two membranes close to each other. Cultures were conducted for 7 or 14 days. Apoptosis, mitochondrial potential, and the production of reactive oxygen species and lactate by HUVECs were investigated. The results indicate that fluctuations in glucose concentration have a stronger negative effect on HUVECs viability than constant high glucose concentration. High and fluctuating glucose concentrations slow down cell proliferation compared to the culture carried out in the medium with normal glucose concentration. In conclusion, HUASMCs affect the viability of HUVECs when both types of cells are co-cultured in medium with normal or variable glucose concentration.

High glucose induces apoptosis, glycogen accumulation and suppresses protein synthesis in muscle cells of olive flounder Paralichthys olivaceus

The effect and the mechanism of high glucose on fish muscle cells are not fully understood. In the present study, muscle cells of olive flounder (Paralichthys olivaceus) were treated with high glucose (33 mM) in vitro. Cells were incubated in three kinds of medium containing 5 mM glucose, 5 mM glucose and 28 mM mannitol (as an isotonic contrast) or 33 mM glucose named the Control group, the Mannitol group and the high glucose (HG) group, respectively. Results showed that high glucose increased the ADP:ATP ratio and the reactive oxygen species (ROS) level, decreased mitochondrial membrane potential (MMP), induced the release of cytochrome C (CytC) and cell apoptosis. High glucose also led to cell glycogen accumulation by increasing the glucose uptake ability and affecting the mRNA expressions of glycogen synthase and glycogen phosphorylase. Meanwhile, it activated AMP-activated protein kinase (AMPK), inhibited the activity of mammalian target of rapamycin (mTOR) signalling pathway and the expressions of myogenic regulatory factors (MRF). The expressions of myostatin-1 (mstn-1) and E3 ubiquitin ligases including muscle RING-finger protein 1 (murf-1) and muscle atrophy F-box protein (mafbx) were also increased by the high glucose treatment. No difference was found between the Mannitol group and the Control group. These results demonstrate that high glucose has the effects of inducing apoptosis, increasing glycogen accumulation and inhibiting protein synthesis on muscle cells of olive flounder. The mitochondria-mediated apoptotic signalling pathway, AMPK and mTOR pathways participated in these biological effects.

Intermittent exposure of cultured endothelial cells to physiologically relevant fructose concentrations has a profound impact on nitric oxide production and bioenergetics

Hyperglycaemia is known to induce endothelial dysfunction and changes in metabolic function, which could be implicated in diabetes-induced cardiovascular disease. To date, however, little is known about the impact of physiologically relevant concentrations of fructose on endothelial cells. A novel in vitro model was devised to establish the impact of substitution of a small proportion of glucose with an equal concentration (0.1 mM or 1 mM) of fructose on EA.hy926 endothelial cells during periodic carbohydrate “meals” superimposed on a normoglycaemic (5.5 mM) background. Parallel experiments were conducted using meals consisting of normoglycaemic glucose, intermediate glucose (12.5 mM) or profound hyperglycaemia (25 mM), each delivered for 2 h, with and without substituted fructose over 50 h. Outcome measures included nitrite as a surrogate marker of the mediator of healthy endothelial function, nitric oxide (NO), and a range of bioenergetic parameters using a metabolic analyser. Despite its relatively low proportion of carbohydrate load, intermittent fructose induced a substantial reduction (approximately 90%) in NO generation in cells treated with either concentration of fructose. Cell markers of oxidative stress were not altered by this treatment regimen. However, the cells experienced a marked increase in metabolic activity induced by fructose, irrespective of the glucose concentration delivered simultaneously in the “meals”. Indeed, glucose alone failed to induce any metabolic impact in this model. Key metabolic findings were a 2-fold increase in basal oxygen consumption rate and a similar change in extracellular acidification rate–a marker of glycolysis. Non-metabolic oxygen consumption also increased substantially in cells exposed to fructose. There was no difference between results with 0.1 mM fructose and those with 1 mM fructose. Low, physiologically relevant concentrations of fructose, delivered in a pattern that mimics mealtime consumption, had a profound impact on endothelial function and bioenergetics in an in vitro cell model. The results suggest that endothelial cells are exquisitely sensitive to circulating fructose; the potential ensuing dysfunction could have major implications for development of atherosclerotic disease associated with high fructose consumption.

Impact of Stress Hyperglycemia on No-Reflow Phenomenon in Patients with ST Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

Background:

Stress hyperglycemia is a common finding during acute myocardial infarction and associated with poor prognosis. To reduce the occurrence of no-reflow, prognostic factors must be identified before primary percutaneous coronary intervention (PPCI). Our objective was to investigate the impact of stress hyperglycemia in non-diabetic and diabetic patients on no-reflow phenomenon after PPCI.

Methods:

The study comprised 480 patients with ST elevation myocardial infarction (STEMI) who were managed by PPCI. Patients were classified into two groups according to thrombolysis in myocardial infarction (TIMI) flow grade: Group I (Patients with normal flow, TIMI 3 flow) and Group II (Patients with no-reflow, TIMI 0-2 flow). Patients were analyzed for clinical outcomes including mortality and major adverse cardiac events.

Results:

Incidence of stress hyperglycemia was 14.8% in non-diabetic patients and 22.2% in diabetic patients; the incidence of no-reflow phenomenon was 13.5% and no-reflow was significantly higher in patients with stress hyperglycemia. Multivariate regression analysis identified the independent predictors of no-reflow phenomenon: stress hyperglycemia OR 3.247 (CI95% 1.656–6.368, P = 0.001), Killip class >1 OR 1.893 (CI95% 1.004–3.570, P = 0.049) and cardiogenic shock OR 3.778 (CI95% 1.458–9.790, P = 0.006).

Conclusion:

Stress hyperglycemia was associated with higher incidence of no-reflow phenomenon. The independent predictors of no-reflow were stress hyperglycemia, Killip class >1 and cardiogenic shock.

Glycaemia dynamics in gestational diabetes mellitus

Pregnant women may develop gestational diabetes mellitus (GDM), a disease of pregnancy characterised by maternal and fetal hyperglycaemia with hazardous consequences to the mother, the fetus, and the newborn. Maternal hyperglycaemia in GDM results in fetoplacental endothelial dysfunction. GDM-harmful effects result from chronic and short periods of hyperglycaemia. Thus, it is determinant to keep glycaemia within physiological ranges avoiding short but repetitive periods of hyper or hypoglycaemia. The variation of glycaemia over time is defined as 'glycaemia dynamics'. The latter concept regards with a variety of mechanisms and environmental conditions leading to blood glucose handling. In this review we summarized the different metrics for glycaemia dynamics derived from quantitative, plane distribution, amplitude, score values, variability estimation, and time series analysis. The potential application of the derived metrics from self-monitoring of blood glucose (SMBG) and continuous glucose monitoring (CGM) in the potential alterations of pregnancy outcome in GDM are discussed.

Metabolic Treatment of Wolfram Syndrome

Wolfram Syndrome (WS) is a very rare genetic disorder characterized by several symptoms that occur from childhood to adulthood. Usually, the first clinical sign is non-autoimmune diabetes even if other clinical features (optic subatrophy, neurosensorial deafness, diabetes insipidus) may be present in an early state and may be diagnosed after diabetes’ onset. Prognosis is poor, and the death occurs at the median age of 39 years as a consequence of progressive respiratory impairment, secondary to brain atrophy and neurological failure. The aim of this paper is the description of the metabolic treatment of the WS. We reported the experience of long treatment in patients with this syndrome diagnosed in pediatric age and followed also in adult age. It is known that there is a correlation between metabolic control of diabetes, the onset of other associated symptoms, and the progression of the neurodegenerative alterations. Therefore, a multidisciplinary approach is necessary in order to prevent, treat and carefully monitor all the comorbidities that may occur. An extensive understanding of WS from pathophysiology to novel possible therapy is fundamental and further studies are needed to better manage this devastating disease and to guarantee to patients a better quality of life and a longer life expectancy.

Significance of Glycemic Variability in Diabetes Mellitus

The goal of diabetes treatment is to maintain good glycemic control, prevent the development and progression of diabetic complications, and ensure the same quality of life and life expectancy as healthy people. Hemoglobin A1c (HbA1c) is used as an index of glycemic control, but strict glycemic control using HbA1c as an index may lead to severe hypoglycemia and cardiovascular death. Glycemic variability (GV), such as excessive hyperglycemia and hypoglycemia, is associated with diabetic vascular complications and has been recognized as an important index of glycemic control. Here, we reviewed the definition and evaluated the clinical usefulness of GV, and its relationship with diabetic complications and therapeutic strategies to reduce GV.

Implications of fasting plasma glucose variability on the risk of incident peripheral artery disease in a population without diabetes: a nationwide population-based cohort study

Background

Diabetes have been known as a traditional risk factor of developing peripheral artery disease (PAD). However, the study evaluating the impact of long-term glycemic variability on the risk of developing PAD is limited, especially in a general population without diabetes.

Methods

We included 152,931 individuals without diabetes from the Korean National Health Insurance Service–Health Screening Cohort. Fasting plasma glucose (FPG) variability was measured using coefficient variance (FPG-CV), standard deviation (FPG-SD), and variability independent of the mean (FPG-VIM).

Results

A total of 16,863 (11.0%) incident cases of PAD were identified during a median follow-up of 8.3 years. Kaplan–Meier curves showed a progressively increasing risk of PAD in the higher quartile group of FPG variability than in the lowest quartile group (log rank P < 0.001). Multivariable Cox proportional hazard analysis showed the hazard ratio for PAD prevalence as 1.11 (95% CI 1.07–1.16, P < 0.001) in the highest FPG-CV quartile than in the lowest FPG-CV quartile after adjusting for confounding variables, including mean FPG. Similar degree of association was shown in the FPG-SD and FPG-VIM. In sensitivity analysis, the association between FPG variability and the risk of developing PAD persisted even after the participants were excluded based on previously diagnosed diseases, including stroke, coronary artery disease, congestive heart failure, chronic kidney disease, or current smokers or drinkers. Subgroup analysis demonstrated that the effects of FPG variability on the risk of PAD were more powerful in subgroups of younger age, regular exercisers, and those with higher income.

Conclusions

Increased long-term glycemic variability may have a significant prognostic effect for incident PAD in individuals without diabetes.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01448-1.

The Impact of Hypo- and Hyperglycemia on Cognition and Brain Development in Young Children with Type 1 Diabetes

Human and experimental animal data suggest both hyperglycemia and hypoglycemia can lead to altered brain structure and neurocognitive function in type 1 diabetes (T1D). Young children with T1D are prone to extreme fluctuations in glucose levels. The overlap of these potential dysglycemic insults to the brain during the time of most active brain and cognitive development may cause cellular and structural injuries that appear to persist into adult life. Brain structure and cognition in persons with T1D are influenced by age of onset, exposure to glycemic extremes such as severe hypoglycemic episodes, history of diabetic ketoacidosis, persistent hyperglycemia, and glucose variability. Studies using brain imaging techniques have shown brain changes that appear to be influenced by metabolic abnormalities characteristic of diabetes, changes apparent at diagnosis and persistent throughout adulthood. Some evidence suggests that brain injury might also directly contribute to psychological and mental health outcomes. Neurocognitive deficits manifest across multiple cognitive domains. Moreover, impaired executive function and mental health can affect patients' adherence to treatment. This review summarizes the current data on the impact of glycemic extremes on brain structure and cognitive function in youth with T1D and the use of new diabetes technologies that may reduce these complications.

Antioxidants in Hops: Bioavailability, Health Effects and Perspectives for New Products

Hop plant (Humulus lupulus L.) has been used by humans for ages, presumably first as a herbal remedy, then in the manufacturing of different products, from which beer is the most largely consumed. Female hops cones have different useful chemical compounds, an important class being antioxidants, mainly polyphenols. This narrative review describes the main antioxidants in hops, their bioavailability and biological effects, and the results obtained by now in the primary and secondary prevention of several non-communicable diseases, such as the metabolic syndrome related diseases and oncology. This article presents in vitro and in vivo data in order to better understand what was accomplished in terms of knowledge and practice, and what needs to be clarified by additional studies, mainly regarding xantohumol and its derivates, as well as regarding the bitter acids of hops. The multiple protective effects found by different studies are hindered up to now by the low bioavailability of some of the main antioxidants in hops. However, there are new promising products with important health effects and perspectives of use as food supplements, in a market where consumers increasingly search for products originating directly from plants.

Repeated glucose spikes and insulin resistance synergistically deteriorate endothelial function and bardoxolone methyl ameliorates endothelial dysfunction

Background

Both insulin resistance and postprandial glucose spikes are known for their potential to induce vascular endothelial dysfunction in individuals with metabolic syndrome. However, these factors are inextricable, and therefore, their relative contributions to inducing endothelial dysfunction remain elusive. In this study, we aimed to disentangle the effects of these factors and clarify whether bardoxolone methyl (CDDO-Me), a novel nuclear factor erythroid 2-related factor 2 (Nrf2) activator, protects against glucose spike-induced endothelial dysfunction.

Methods

We induced glucose spikes twice daily for a duration of 1 week to rats fed a standard/control diet (CD) and Western-type diet (WTD). Endothelium-dependent relaxation (EDR) was evaluated using isolated thoracic aortas. Gene expression and dihydroethidium (DHE)-fluorescence studies were carried out; the effect of CDDO-Me on aortic endothelial dysfunction in vivo was also evaluated.

Results

Neither WTD-induced insulin resistance nor pure glucose spikes significantly deteriorated EDR. However, under high-glucose (20 mM) conditions, the EDR of thoracic aortas of WTD-fed rats subjected to glucose spikes was significantly impaired. In this group of rats, we observed significantly enhanced DHE fluorescence as a marker of reactive oxygen species, upregulation of an oxidative stress-related gene (NOX2), and downregulation of an antioxidant gene (SOD2) in the thoracic aortas. As expected, treatment of the thoracic aorta of this group of rats with antioxidant agents significantly improved EDR. We also noted that pretreatment of aortas from the same group with CDDO-Me attenuated endothelial dysfunction, accompanied by a correction of the redox imbalance, as observed in gene expression and DHE fluorescence studies.

Conclusions

For the first time, we showed that insulin resistance and glucose spikes exert a synergistic effect on aortic endothelial dysfunction. Furthermore, our study reveals that CDDO-Me ameliorates endothelial dysfunction caused by glucose spikes in a rat model of metabolic syndrome.

Glucose levels during gestational diabetes pregnancy and the risk of developing postpartum diabetes or prediabetes

BACKGROUND

Blood glucose levels during pregnancy may reflect the severity of insulin secretory defects and/or insulin resistance during gestational diabetes mellitus (GDM) pregnancy. We hypothesized that suboptimal glycemic control in women with GDM could increase the risk of postpartum type 2 diabetes mellitus (T2DM) or prediabetes. Our objective was to evaluate the impact of plasma glucose levels throughout GDM pregnancy on the risk of postpartum T2DM or prediabetes.

METHODS

The medical records of 706 women with GDM who underwent a postpartum 75-g, 2-hour oral glucose tolerance test at our institution between January 2011 and December 2018 were reviewed. These women were classified into 2 groups according to glycemic control during pregnancy: ≤ 1 occasion of either fasting glucose ≥ 95 mg/dL or 2-hour postprandial glucose ≥ 120 mg/dL was defined as optimal glycemic control or else was classified as suboptimal glycemic control. Rates of postpartum T2DM and prediabetes were compared between women with optimal (n = 505) and suboptimal (n = 201) glycemic control.

RESULTS

The rates of postpartum T2DM and prediabetes were significantly higher in the suboptimal glycemic control group than in the optimal glycemic control group: 22.4% vs. 3.0%, P < 0.001 for T2DM and 45.3% vs. 23.5%, P < 0.001 for prediabetes. In a multivariate analysis, suboptimal glucose control during pregnancy was an independent risk factor for developing either postpartum T2DM or prediabetes. The adjusted odds ratios were 8.4 (95% confidence interval, 3.5-20.3) for T2DM and 3.9 (95% confidence interval, 2.5-6.1) for prediabetes.

CONCLUSION

Our findings suggest that blood glucose levels during GDM pregnancy have an impact on the risk of postpartum T2DM and prediabetes.

Perspectives of glycemic variability in diabetic neuropathy: a comprehensive review

Diabetic neuropathy is one of the most prevalent chronic complications of diabetes, and up to half of diabetic patients will develop diabetic neuropathy during their disease course. Notably, emerging evidence suggests that glycemic variability is associated with the pathogenesis of diabetic complications and has emerged as a possible independent risk factor for diabetic neuropathy. In this review, we describe the commonly used metrics for evaluating glycemic variability in clinical practice and summarize the role and related mechanisms of glycemic variability in diabetic neuropathy, including cardiovascular autonomic neuropathy, diabetic peripheral neuropathy and cognitive impairment. In addition, we also address the potential pharmacological and non-pharmacological treatment methods for diabetic neuropathy, aiming to provide ideas for the treatment of diabetic neuropathy.

Zhang et al. describe metrics for evaluating glycaemic variability (GV) in clinical practice and summarize the role and related mechanisms of GV in diabetic neuropathy, including cardiovascular autonomic neuropathy, diabetic peripheral neuropathy and cognitive impairment. They aim to stimulate ideas for the treatment of diabetic neuropathy.

Age moderates the relationships between obesity, glucose variability, and intensive care unit mortality: a retrospective cohort study

BACKGROUND

Although the associations between obesity, glucose variability (GV), and Intensive Care Unit (ICU) mortality have been studied extensively, whether age moderates these associations is not well understood.

MATERIALS AND METHODS

The medical records of 1062 patients, who were admitted into ICU at Sir Run Run Shaw Hospital (Zhejiang, China), were studied. Logistic regression was used to test the associations between obesity, GV, and ICU mortality. Furthermore, the moderation effect of age was tested.

RESULTS

After controlling for covariates, the underweight group had the highest odds of death (OR 2.38, 95% CI 1.43-3.95, p < 0.001) in comparison with the control group (overweight). However, normal weight (OR 1.29, 95% CI 0.88-1.89, p = 0.185) and obese (OR 1.08, 95% CI 0.61-1.90, p = 0.790) groups had similar odds of death, compared to the overweight group. Age significantly moderated the association between obesity and mortality, where being overweight was more advantageous than being normal weight in older adults (B = 0.03, SE = 0.01, OR 1.03, 95% CI 1.001-1.06, p = 0.045). Meanwhile, higher GV predicted greater mortality in adjusted models (OR 1.23, 95% CI 1.06-1.42, p = 0.005). We also found an interaction between age and GV (B = - 0.01, SE = 0.01, OR 0.99, 95% CI 0.98-0.999, p = 0.025), which suggested that the association between GV and mortality becomes weaker with increasing age.

CONCLUSIONS

With increasing age, the association between BMI and mortality becomes stronger and the association between glucose variability and mortality becomes weaker. Future studies should investigate the underlying mechanisms of such phenomenon and the causal relationship between obesity, GV, and ICU mortality.

Diabetic Wound-Healing Science

Diabetes mellitus is an increasingly prevalent chronic metabolic disease characterized by prolonged hyperglycemia that leads to long-term health consequences. It is estimated that impaired healing of diabetic wounds affects approximately 25% of all patients with diabetes mellitus, often resulting in lower limb amputation, with subsequent high economic and psychosocial costs. The hyperglycemic environment promotes the formation of biofilms and makes diabetic wounds difficult to treat. In this review, we present updates regarding recent advances in our understanding of the pathophysiology of diabetic wounds focusing on impaired angiogenesis, neuropathy, sub-optimal chronic inflammatory response, barrier disruption, and subsequent polymicrobial infection, followed by current and future treatment strategies designed to tackle the various pathologies associated with diabetic wounds. Given the alarming increase in the prevalence of diabetes, and subsequently diabetic wounds, it is imperative that future treatment strategies target multiple causes of impaired healing in diabetic wounds.

Variability in Cardiometabolic and Inflammatory Parameters and Cognitive Decline

INTRODUCTION

The relationship between variability in cardiometabolic and inflammatory parameters and cognitive changes is unknown. This study investigates the association of visit-to-visit variability in BMI, mean arterial pressure, total cholesterol, triglycerides, HbA1c, high-sensitivity C-reactive protein, ferritin, and fibrinogen with cognitive decline.

METHODS

This population-based cohort study included 2,260 individuals (mean age=63.0 [SD=7.5] years) free of cognitive diseases who underwent ≥3 clinical measurements from 2004 to 2019. Variability was expressed as variability independent of the mean across visits. Participants were divided on the basis of quartiles of variability score, a scoring system generated to explore the composite effect of parameter variability (range=0-24), where 0 points were assigned for Quartile 1, 1 point was assigned for Quartile 2, 2 points were assigned for Quartile 3, and 3 points were assigned for Quartile 4, each for the variability of 8 parameters measured as variability independent of the mean. Linear mixed models evaluated the longitudinal associations with cognitive decline in memory and verbal fluency. All analyses were conducted in 2020-2021.

RESULTS

Higher BMI, mean arterial pressure, total cholesterol, HbA1c, and ferritin variability were linearly associated with cognitive decline irrespective of their mean values. In addition, participants in the highest quartile of variability score had a significantly worse cognitive decline rate in memory (-0.0224 points/year, 95% CI= -0.0319, -0.0129) and verbal fluency (-0.0088 points/year, 95% CI= -0.0168, -0.0008) than those in the lowest quartile.

CONCLUSIONS

A higher variability in cardiometabolic and inflammatory parameters was significantly associated with cognitive decline. Stabilizing these parameters may serve as a target to preserve cognitive functioning.

Alterations of transcriptome expression, cell cycle, and mitochondrial superoxide reveal foetal endothelial dysfunction in Saudi women with gestational diabetes mellitus

Gestational diabetes mellitus (GDM) affects one in four Saudi women and is associated with high risks of cardiovascular diseases in both the mother and foetus. It is believed that endothelial cells (ECs) dysfunction initiates these diabetic complications. In this study, differences in the transcriptome profiles, cell cycle distribution, and mitochondrial superoxide (MTS) between human umbilical vein endothelial cells (HUVECs) from GDM patients and those from healthy (control) subjects were analysed. Transcriptome profiles were generated using high-density expression microarray. The selected four altered genes were validated using qRT-PCR. MTS and cell cycle were analysed by flow cytometry. A total of 84 altered genes were identified, comprising 52 upregulated and 32 downregulated genes in GDM.HUVECs. Our selection of the four interested altered genes (TGFB2, KITLG, NEK7, and IGFBP5) was based on the functional network analysis, which revealed that these altered genes are belonging to the highest enrichment score associated with cellular function and proliferation; all of which may contribute to ECs dysfunction. The cell cycle revealed an increased percentage of cells in the G2/M phase in GDM.HUVECs, indicating cell cycle arrest. In addition, we found that GDM.HUVECs had increased MTS generation. In conclusion, GDM induces persistent impairment of the biological functions of foetal ECs, as evidenced by analyses of transcriptome profiles, cell cycle, and MTS even after ECs culture in vitro for several passages under normal glucose conditions.

Meal-time glycaemia in adults with type 1 diabetes using multiple daily injections vs insulin pump therapy following carbohydrate-counting education and bolus calculator provision

AIMS

To compare meal-time glycaemia in adults with type 1 diabetes mellitus (T1D) managed with multiple daily injections (MDI) vs. insulin pump therapy (IPT), using self-monitoring blood glucose (SMBG), following diabetes education.

METHODS

Adults with T1D received carbohydrate-counting education and a bolus calculator: MDI (Roche Aviva Expert) and IPT (pump bolus calculator). All then wore 3-weeks of masked-CGM (Enlite, Medtronic). Meal-times were assessed by two approaches: 1) Set time-blocks (breakfast 06:00-10:00hrs; lunch 11:00-15:00hrs; dinner 17:00-21:00hrs) and 2) Bolus-calculator carbohydrate entries signalling meal commencement. Post-meal masked-CGM time-in-range (TIR) 3.9-10.0 mmol/L was the primary outcome.

RESULTS

MDI(n = 61) and IPT (n = 59) participants were equivalent in age, sex, diabetes duration and HbA1c. Median (IQR) education time provided did not differ (MDI: 1.1 h (0.75, 1.5) vs. IPT: 1.1 h (1.0, 2.0); p = 0.86). Overall, daytime (06:00-24:00hrs), lunch and dinner TIR did not differ for MDI vs. IPT participants but was greater for breakfast with IPT in both analyses with a mean difference of 12.8%, (95 CI 4.8, 20.9); p = 0.002 (time-block analysis).

CONCLUSION

After diabetes education, MDI and IPT use were associated with similar day-time glycemia, though IPT users had significantly greater TIR during the breakfast period. With education, meal-time glucose levels are comparable with use of MDI vs. pumps.

Vascular and Myocardial Function in Young People with Type 1 Diabetes Mellitus: Insulin Pump Therapy Versus Multiple Daily Injections Insulin Regimen

INTRODUCTION

Multiple daily injections (MDI) and continuous subcutaneous insulin infusion (CSII) are two modalities of treating type 1 diabetes mellitus (T1DM). The benefits of CSII on long-term metabolic control and outcomes compared to those of MDI are still debated. We investigated both vascular function and myocardial performance in T1DM adolescents on MDI or CSII treatment.

METHODS

One hundred twenty-three T1DM subjects (mean age 14.16±2.55 years), 63 on MDI regimen, 60 on CSII, and 57 controls were enrolled. Anthropometric and biochemical characteristics were evaluated. Ultrasound assessments of carotid intima-media thickness (cIMT), flow-mediated dilatation of brachial artery, anteroposterior diameter of the infrarenal abdominal aorta (APAO), and transthoracic echocardiography were performed.

RESULTS

T1DM subjects on the CSII regimen showed better glycemic control than those on MDI, expressed as glycated haemoglobin (HbA1c). c-IMT and APAO were higher in MDI than CSII patients (0.61±0.11 mm vs. 0.56±0.07 mm, p=0.04; 13.61±3.29 mm vs. 11.65±1.84 mm, p=0.01, respectively). Left and right Tei index and left E/e' ratio were higher in MDI than CSII subjects (0.82±0.40 vs. 0.52±0.19, p=0.002; 0.86±0.41 vs. 0.64±0.1, p=0.02; 5.89±2.0 vs. 4.73±1.59, p=0.02, respectively). Multiple regression analyses showed that glucose level, HbA1c and diabetes onset were significantly related to vascular and echocardiographic parameters in MDI and CSII patients.

CONCLUSIONS

CSII regimen in T1DM adolescents improves glycemic control and seems to ameliorate endothelial function and global myocardial performance as compared to MDI therapy.

Hypoglycemic activity of puerarin through modulation of oxidative stress and mitochondrial function via AMPK

Hyperglycemia is the dominant phenotype of diabetes and the main contributor of diabetic complications. Puerarin is widely used in cardiovascular diseases and diabetic vascular complications. However, little is known about its direct effects on diabetes. The aim of our study is to investigate its antidiabetic effect in vivo and in vitro, and explore the underlying mechanism. We used type I diabetic mice induced by streptozotocin to observe the effects of puerarin on glucose metabolism. In addition, oxidative stress and hepatic mitochondrial respiratory activity were evaluated in type I diabetic mice. In vitro, glucose consumption in HepG2 cells was assayed along with the qPCR detection of glucogenesis genes expression. Moreover, ATP production was examined and phosphorylation of AMPK was determined using Western blot. Finally, the molecular docking was performed to predict the potential interaction of puerarin with AMPK utilizing program LibDock of Discovery Studio 2018 software. The results showed that puerarin improved HepG2 glucose consumption and upregulated the glucogenesis related genes expression. Also, puerarin lowered fasting and fed blood glucose with improvement of glucose tolerance in type I diabetic mice. Further mechanism investigation showed that puerarin suppressed oxidative stress and improved hepatic mitochondrial respiratory function with enhancing ATP production and activating phosphorylation of AMPK. Docking study showed that puerarin interacted with AMPK activate site and enhancing phosphorylation. Taken together, these findings indicated that puerarin exhibited the hypoglycemic effect through attenuating oxidative stress and improving mitochondrial function via AMPK regulation, which may serve as a potential therapeutic option for diabetes treatment.

Glucose Variability: How Does It Work?

A growing body of evidence points to the role of glucose variability (GV) in the development of the microvascular and macrovascular complications of diabetes. In this review, we summarize data on GV-induced biochemical, cellular and molecular events involved in the pathogenesis of diabetic complications. Current data indicate that the deteriorating effect of GV on target organs can be realized through oxidative stress, glycation, chronic low-grade inflammation, endothelial dysfunction, platelet activation, impaired angiogenesis and renal fibrosis. The effects of GV on oxidative stress, inflammation, endothelial dysfunction and hypercoagulability could be aggravated by hypoglycemia, associated with high GV. Oscillating hyperglycemia contributes to beta cell dysfunction, which leads to a further increase in GV and completes the vicious circle. In cells, the GV-induced cytotoxic effect includes mitochondrial dysfunction, endoplasmic reticulum stress and disturbances in autophagic flux, which are accompanied by reduced viability, activation of apoptosis and abnormalities in cell proliferation. These effects are realized through the up- and down-regulation of a large number of genes and the activity of signaling pathways such as PI3K/Akt, NF-κB, MAPK (ERK), JNK and TGF-β/Smad. Epigenetic modifications mediate the postponed effects of glucose fluctuations. The multiple deteriorative effects of GV provide further support for considering it as a therapeutic target in diabetes.