Acarbose ameliorates spontaneous type‑2 diabetes in db/db mice by inhibiting PDX‑1 methylation

Treatment of type 2 diabetes mellitus with stem cells and antidiabetic drugs: a dualistic and future-focused approach

Type 2 Diabetes Mellitus (T2DM) accounts for more than 90% of total diabetes mellitus cases all over the world. Obesity and lack of balance between energy intake and energy expenditure are closely linked to T2DM. Initial pharmaceutical treatment and lifestyle interventions can at times lead to remission but usually help alleviate it to a certain extent and the condition remains, thus, recurrent with the patient being permanently pharmaco-dependent. Mesenchymal stromal cells (MSCs) are multipotent, self-renewing cells with the ability to secrete a variety of biological factors that can help restore and repair injured tissues. MSC-derived exosomes possess these properties of the original stem cells and are potentially able to confer superior effects due to advanced cell-to-cell signaling and the presence of stem cell-specific miRNAs. On the other hand, the repository of antidiabetic agents is constantly updated with novel T2DM disease-modifying drugs, with higher efficacy and increasingly convenient delivery protocols. Delving deeply, this review details the latest progress and ongoing studies related to the amalgamation of stem cells and antidiabetic drugs, establishing how this harmonized approach can exert superior effects in the management and potential reversal of T2DM.

Oral Semaglutide under Human Protocols and Doses Regulates Food Intake, Body Weight, and Glycemia in Diet-Induced Obese Mice

The first oral form of the glucagon-like peptide-1 receptor agonist, oral semaglutide, has recently been launched and potently controls glycemia and body weight in subjects with type 2 diabetes. This drug carries the absorption enhancer and requires specific protocols of administration. The mechanism of action of oral semaglutide is not fully understood, for which an appropriate experimental model is required. This study explores the metabolic effects of oral semaglutide in mice under human protocols and doses. Oral semaglutide was bolus and once daily injected into high-fat diet-induced obese (DIO) mice under human protocols, followed by monitoring blood glucose, food intake, and body weight. Oral semaglutide 0.23 mg/kg, a comparable human dose (14 mg) in a small volume of water under human protocols rapidly decreased blood glucose and food intake and continuously reduced food intake and weight gain for 3 days in DIO mice. At 0.7 mg/kg (42 mg), this drug was somewhat more potent. Oral semaglutide with human protocols and doses rapidly reduces blood glucose and food intake and continuously suppresses feeding and weight in DIO mice. This study establishes mice as a model suitable for analyzing the mechanism of anti-obesity/diabetes actions of oral semaglutide.

PDX-1: A Promising Therapeutic Target to Reverse Diabetes

The pancreatic duodenum homeobox-1 (PDX-1) is a transcription factor encoded by a Hox-like homeodomain gene that plays a crucial role in pancreatic development, β-cell differentiation, and the maintenance of mature β-cell functions. Research on the relationship between PDX-1 and diabetes has gained much attention because of the increasing prevalence of diabetes melitus (DM). Recent studies have shown that the overexpression of PDX-1 regulates pancreatic development and promotes β-cell differentiation and insulin secretion. It also plays a vital role in cell remodeling, gene editing, and drug development. Conversely, the absence of PDX-1 increases susceptibility to DM. Therefore, in this review, we summarized the role of PDX-1 in pancreatic development and the pathogenesis of DM. A better understanding of PDX-1 will deepen our knowledge of the pathophysiology of DM and provide a scientific basis for exploring PDX-1 as a potential target for treating diabetes.

Geroscience-guided repurposing of FDA-approved drugs to target aging: A proposed process and prioritization

Common chronic diseases represent the greatest driver of rising healthcare costs, as well as declining function, independence, and quality of life. Geroscience-guided approaches seek to delay the onset and progression of multiple chronic conditions by targeting fundamental biological pathways of aging. This approach is more likely to improve overall health and function in old age than treating individual diseases, by addressing aging the largest and mostly ignored risk factor for the leading causes of morbidity in older adults. Nevertheless, challenges in repurposing existing and moving newly discovered interventions from the bench to clinical care have impeded the progress of this potentially transformational paradigm shift. In this article, we propose the creation of a standardized process for evaluating FDA-approved medications for their geroscience potential. Criteria for systematically evaluating the existing literature that spans from animal models to human studies will permit the prioritization of efforts and financial investments for translating geroscience and allow immediate progress on the design of the next Targeting Aging with MEtformin (TAME)-like study involving such candidate gerotherapeutics.

Epigallocatechin-3-gallate alleviates type 2 diabetes mellitus via β-cell function improvement and insulin resistance reduction

OBJECTIVES

Epigallocatechin-3-gallate (EGCG) has a good therapeutic effect on type 2 diabetes mellitus (T2DM). This work was designed to explore EGCG's effectiveness in insulin resistance (IR) and pancreas islet β-cell function in a rat model of T2DM.

MATERIALS AND METHODS

Eight-week-old male Sprague Dawley rats were randomly divided into 6 groups, including the Control (normal diet), Diabetes (high-sucrose high-fat [HSHF] diet combined with tail vein injection of streptozotocin [STZ] for T2DM induction) and Treatment Diabetic rats which were treated with metformin [500 mg/kg/d] or EGCG [25, 50 or 100 mg/kg/d] intragastric administration for 10 weeks. With the exception of control animals, the other groups were fed the HSHF diet. EGCG's effects on IR and insulin secretion were assessed by measuring body weights, and fasting blood glucose (FBG), postprandial blood glucose (PBG) and insulin levels. The morphological and molecular changes of pancreas islet β-cells were examined by hematoxylin-eosin (H&E) staining, transmission electron microscopy (TEM) and immunofluorescence.

RESULTS

Rats fed the HSHF diet combined with STZ treatment had increased body weights and blood glucose amounts, accompanied by IR and impaired β-cell function, induced T2DM, and EGCG dose-dependently restored the above indicators. Additionally, EGCG upregulated the pancreatic transcription factors pancreatic duodenal homeobox protein-1 (PDX-1) and musculoaponeurotic fibrosarcoma oncogene homolog A (MafA).

CONCLUSION

These results suggest that EGCG reduces blood glucose amounts, and improve IR and islet β-cell disorder in T2DM.

Modulating effects of capsaicin on glucose homeostasis and the underlying mechanism

Abnormal glucose homeostasis is linked to a variety of metabolic syndromes, such as insulin resistance, obesity, type-2 diabetes mellitus, hypertension and cardiovascular diseases. Maintenance of normal glucose homeostasis is important for the body to keep normal biological functions. As the major bioactive ingredient in chili peppers responsible for the pungent flavor, capsaicin has been reported to effectively improve glucose homeostasis with low cytotoxicity. In this review, the modulating effects of capsaicin on glucose homeostasis in cell models, animal models and human trials are summarized through both TRPV1 dependent and TRPV1 independent pathways. The relevant molecular mechanisms underlying its regulatory effects are also evaluated. Understanding the effects and mechanisms of capsaicin on glucose metabolism could provide theoretical evidence for its application in the food and pharmaceutical industries.

Development of the Diabetic Kidney Disease Mouse Model Culturing Embryos in α-Minimum Essential Medium In Vitro, and Feeding Barley Diet Attenuated the Pathology

Diabetic kidney disease (DKD) is a critical complication associated with diabetes; however, there are only a few animal models that can be used to explore its pathogenesis. In the present study, we established a mouse model of DKD using a technique based on the Developmental Origins of Health and Disease theory, i.e., by manipulating the embryonic environment, and investigated whether a dietary intervention could ameliorate the model's pathology. Two-cell embryos were cultured in vitro in α-minimum essential medium (MEM; MEM mice) or in standard potassium simplex-optimized medium (KSOM) as controls (KSOM mice) for 48 h, and the embryos were reintroduced into the mothers. The MEM and KSOM mice born were fed a high-fat, high-sugar diet for 58 days after they were 8 weeks old. Subsequently, half of the MEM mice and all KSOM mice were fed a diet containing rice powder (control diet), and the remaining MEM mice were fed a diet containing barley powder (barley diet) for 10 weeks. Glomerulosclerosis and pancreatic exhaustion were observed in MEM mice, but not in control KSOM mice. Renal arteriolar changes, including intimal thickening and increase in the rate of hyalinosis, were more pronounced in MEM mice fed a control diet than in KSOM mice. Immunostaining showed the higher expression of transforming growth factor beta (TGFB) in the proximal/distal renal tubules of MEM mice fed a control diet than in those of KSOM mice. Pathologies, such as glomerulosclerosis, renal arteriolar changes, and higher TGFB expression, were ameliorated by barley diet intake in MEM mice. These findings suggested that the MEM mouse is an effective DKD animal model that shows glomerulosclerosis and renal arteriolar changes, and barley intake can improve these pathologies in MEM mice.

Epigenetic Regulation of PDX-1 in Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is a metabolic disease characterized by hyperglycemia which is caused by insufficient insulin secretion or insulin resistance. Interaction of genetic, epigenetic and environmental factors plays a significant role in the development of T2DM. Several environmental factors including diet and lifestyle, as well as age have been associated with an increased risk for T2DM. It has been demonstrated that these environmental factors may affect global epigenetic status, and alter the expression of susceptible genes, thereby contributing to the pathogenesis of T2DM. In recent years, a growing body of molecular and genetic studies in diabetes have been focused on the ways to restore the numbers or function of β-cells in order to reverse a range of metabolic consequences of insulin deficiency. The pancreatic duodenal homeobox 1 (PDX-1) is a transcriptional factor that is essential for the development and function of islet cells. A number of studies have shown that there is a significant increase in the level of DNA methylation of PDX-1 resulting in reduced activity in T2DM islets. The decrease in PDX-1 activity may be a critical mediator causing dysregulation of pancreatic β cells in T2DM. This article reviews the epigenetic mechanisms of PDX-1 involved in T2DM, focusing on diabetes and DNA methylation, and discusses some potential strategies for the application of PDX-1 in the treatment of diabetes.