Molecular and Biochemical Pathways Encompassing Diabetes Mellitus and Dementia

Clinical significance of vascular endothelial growth factor and endothelin-1 in serum levels as novel indicators for predicting the progression of diabetic nephropathy

Objective: Early diagnosis and intervention of diabetic nephropathy (DN) is necessary to optimize therapy in order to delay the progression of diabetes. This research aimed to reveal the change of vascular endothelial growth factor (VEGF) and endothelin-1 (ET-1) in patients with DN, and to assess possible correlations with glycated hemoglobin (HbAlc) values. Methods: The present study was a retrospective, single-center study conducted at a teaching hospital in the northeast China. A total of 120 patients were divided into proteinuria-positive group ( n = 40), the microalbuminuria group ( n = 40), and the high proteinuria group ( n = 40) according to the urinary albumin excretion rate (UAER), and 40 healthy volunteers were selected as the control group. The levels of VEGF, ET-1 and HbA1c were measured in all subjects and principal component analysis (PCA) was performed to classify and reveal correlations between VEGF, ET-1 and HbA1c. Results: Compared to the control group, a significant difference in the increase of HbA1c was detected in group I, II and III. A significant increase in the concentrations of serum VEGF and ET-1 was also observed. HbA1c in DN patients had proven to be positively correlated with VEGF (r = 0.7941; p < 0. 0001) and ET-1 (r = 0.8504; p < 0.0001) respectively. Conclusion: The elevated levels of VEGF and ET-1 in serum have been proposed as being able to supplement the additional information about the progression of DN. These data suggest that the decrease in endothelial function may be related to poor glycemic control.

Obesity control and liver health in breast cancer: Normalized hepatic elasticity after ketogenic diet

Most socially significant diseases, including breast cancer, are undeniably linked to obesity. Recently, a positive relationship between excessive weight and increased risk of breast cancer poor outcomes has been proved. Liver integrity is an essential point during chemotherapy. Consequently, a hepatic safe therapeutic approach for managing obesity in patients with breast cancer should be initiated. Our study aimed to assess the impact of the ketogenic diet on body mass index (BMI) and to evaluate its safety on liver function in female patients with breast cancer. The study comprised 520 women with ductal breast cancer who underwent a 60-day modified ketogenic diet. BMI, prothrombin time (PT), activated partial thromboplastin clotting time (aPTT), aspartate aminotransferase to platelet ratio index (APRI), and ultrasound liver elasticity was evaluated before and after the diet. The results showed a significant decrease in BMI and an improvement in ultrasound liver elasticity in all the participants after completing the diet. Before the KD, the participants' median BMI was 35.0 kg/m2, and after the 60-day diet, the median BMI was reduced to 30.0 kg/m2. No significant liver parameter changes were found after the diet. In conclusion, we can safely promote the keto diet amongst individuals with an increased chance of developing breast cancer for a better disease prevention.

Cognitive dysfunction in diabetes: abnormal glucose metabolic regulation in the brain

Cognitive dysfunction is increasingly recognized as a complication and comorbidity of diabetes, supported by evidence of abnormal brain structure and function. Although few mechanistic metabolic studies have shown clear pathophysiological links between diabetes and cognitive dysfunction, there are several plausible ways in which this connection may occur. Since, brain functions require a constant supply of glucose as an energy source, the brain may be more susceptible to abnormalities in glucose metabolism. Glucose metabolic abnormalities under diabetic conditions may play an important role in cognitive dysfunction by affecting glucose transport and reducing glucose metabolism. These changes, along with oxidative stress, inflammation, mitochondrial dysfunction, and other factors, can affect synaptic transmission, neural plasticity, and ultimately lead to impaired neuronal and cognitive function. Insulin signal triggers intracellular signal transduction that regulates glucose transport and metabolism. Insulin resistance, one hallmark of diabetes, has also been linked with impaired cerebral glucose metabolism in the brain. In this review, we conclude that glucose metabolic abnormalities play a critical role in the pathophysiological alterations underlying diabetic cognitive dysfunction (DCD), which is associated with multiple pathogenic factors such as oxidative stress, mitochondrial dysfunction, inflammation, and others. Brain insulin resistance is highly emphasized and characterized as an important pathogenic mechanism in the DCD.

Exosomes as Promising Nanostructures in Diabetes Mellitus: From Insulin Sensitivity to Ameliorating Diabetic Complications

Diabetes mellitus (DM) is among the chronic metabolic disorders that its incidence rate has shown an increase in developed and wealthy countries due to lifestyle and obesity. The treatment of DM has always been of interest, and significant effort has been made in this field. Exosomes belong to extracellular vesicles with nanosized features (30-150 nm) that are involved in cell-to-cell communication and preserving homeostasis. The function of exosomes is different based on their cargo, and they may contain lipids, proteins, and nucleic acids. The present review focuses on the application of exosomes in the treatment of DM; both glucose and lipid levels are significantly affected by exosomes, and these nanostructures enhance lipid metabolism and decrease its deposition. Furthermore, exosomes promote glucose metabolism and affect the level of glycolytic enzymes and glucose transporters in DM. Type I DM results from the destruction of β cells in the pancreas, and exosomes can be employed to ameliorate apoptosis and endoplasmic reticulum (ER) stress in these cells. The exosomes have dual functions in mediating insulin resistance/sensitivity, and M1 macrophage-derived exosomes inhibit insulin secretion. The exosomes may contain miRNAs, and by transferring among cells, they can regulate various molecular pathways such as AMPK, PI3K/Akt, and β-catenin to affect DM progression. Noteworthy, exosomes are present in different body fluids such as blood circulation, and they can be employed as biomarkers for the diagnosis of diabetic patients. Future studies should focus on engineering exosomes derived from sources such as mesenchymal stem cells to treat DM as a novel strategy.

Enhanced Differentiation Capacity and Transplantation Efficacy of Insulin-Producing Cell Clusters from Human iPSCs Using Permeable Nanofibrous Microwell-Arrayed Membrane for Diabetes Treatment

Although pancreatic islet transplantation is a potentially curative treatment for insulin-dependent diabetes, a shortage of donor sources, low differentiation capacity, and transplantation efficacy are major hurdles to overcome before becoming a standard therapy. Stem cell-derived insulin-producing cells (IPCs) are a potential approach to overcoming these limitations. To improve the differentiation capacity of the IPCs, cell cluster formation is crucial to mimic the 3D structure of the islet. This study developed a biodegradable polycaprolactone (PCL) electrospun nanofibrous (NF) microwell-arrayed membrane permeable to soluble factors. Based on the numerical analysis and experimental diffusion test, the NF microwell could provide sufficient nutrients, unlike an impermeable PDMS (polydimethylsiloxane) microwell. The IPC clusters in the NF microwells showed higher gene expression of insulin and PDX1 and insulin secretion than the PDMS microwells. The IPC clusters in the NF microwell-arrayed membrane could be directly transplanted. Transplanted IPC clusters in the microwells survived well and expressed PDX1 and insulin. Additionally, human c-peptide was identified in the blood plasma at two months after transplantation of the membranes. The NF microwell-arrayed membrane can be a new platform promoting IPC differentiation capacity and realizing an in situ transplantation technique for diabetic patients.