Search Results (186)

Background: Senescence, a state of permanent cell cycle arrest, is a complex cellular phenomenon closely affiliated with age-related diseases and pathological fibrosis. Cellular senescence is now recognized as a significant contributor to organ fibrosis, largely driven by transforming growth factor beta (TGF-β) signaling, such as in metabolic dysfunction-associated steatohepatitis (MASH), idiopathic pulmonary fibrosis (IPF), chronic kidney disease (CKD), and myocardial fibrosis, which can lead to heart failure, cystic fibrosis, and fibrosis in pancreatic tumors, to name a few. MASH is a progressive inflammatory and fibrotic liver condition that has reached pandemic proportions, now considered the largest non-viral contributor to the need for liver transplantation. Methods: We previously studied Oxy210, an anti-fibrotic and anti-inflammatory, orally bioavailable, oxysterol-based drug candidate for MASH, using APOE*3-Leiden.CETP mice, a humanized hyperlipidemic mouse model that closely recapitulates the hallmarks of human MASH. In this model, treatment of mice with Oxy210 for 16 weeks caused significant amelioration of the disease, evidenced by reduced hepatic inflammation, lipid deposition, and fibrosis, atherosclerosis and adipose tissue inflammation. Results: Here we demonstrate increased hepatic expression of senescence-associated genes and senescence-associated secretory phenotype (SASP), correlated with the expression of pro-fibrotic and pro-inflammatorygenes in these mice during the development of MASH that are significantly inhibited by Oxy210. Using the HepG2 human hepatocyte cell line, we demonstrate the induced expression of senescent-associated genes and SASP by TGF-β and inhibition by Oxy210. Conclusions: These findings further support the potential therapeutic effects of Oxy210 mediated in part through inhibition of senescence-driven hepatic fibrosis and inflammation in MASH and perhaps in other senescence-associated fibrotic diseases. Full article

(1) Background: Epidemiological studies link ozone (O₃) exposure to diabetes risk, but mechanisms and early biomarkers remain unclear. (2) Methods: Female mice exposed to 0.5/1.0 ppm O₃ were assessed for glucose tolerance and HOMA (homeostasis model assessment) index. Genes related to impaired glucose tolerance and insulin resistance were screened through the Comparative Toxicogenomics Database (CTD), and verified using quantitative real-time PCR. In addition, liver histopathological observations and the determination of basic biochemical indicators were conducted, and targeted metabolomics analysis was performed on the liver to verify glycogen levels and gene expression. In vitro validation was conducted with HepG2 and Min6 cell lines. (3) Results: Fasting blood glucose and insulin resistance were elevated following O₃ exposure. Given that the liver plays a critical role in glucose metabolism, we further investigated hepatocyte apoptosis and alterations in glycogen metabolism, including reduced glycogen levels and genetic dysregulation. Metabolomics analysis revealed abnormalities in fructose metabolism and glycogen synthesis in the livers of the O₃-exposed group. In vitro studies demonstrated that oxidative stress enhances both liver cell apoptosis and insulin resistance in pancreatic islet β cells. (4) Conclusions: O₃ triggers prediabetes symptoms via hepatic metabolic dysfunction and hepatocyte apoptosis. The identified metabolites and genes offer potential as early biomarkers and therapeutic targets. Full article

Background: Uric acid has been proposed as a diabetogenic factor while its effect on pancreatic β cell function remains elusive. This study aimed to explore the impact of uric acid levels on β cell function and delineate its underlying molecular mechanisms. Methods: Both in vivo hyperuricemia diet-induced mouse models and in vitro pancreatic β cell models were utilized. Results: A progressive decrease in glucose-stimulated insulin secretion and increase in β cell apoptosis were observed in the hyperuricemia diet-induced mouse model, and these could be effectively restored by urate-lowering therapy. The dose- and time-dependent direct effects of uric acid on β cell apoptosis and insulin secretion were further confirmed in both INS-1E cells and primary isolated islets. Mechanistically, the primary role of expression of the endoplasmic reticulum stress marker C/EBP homologous protein (CHOP) was detected by RNA sequencing, and the inflammatory factor NLRP3 and pro-apoptotic genes were significantly upregulated by uric acid treatment. Conclusions: Together, our findings indicate a direct crosstalk between uric acid and β cells via CHOP/NLRP3 pathway, providing a new understanding of the diabetogenic effect of uric acid. Full article

Emerging evidence highlights the profound and lasting impact of severe illnesses such as COVID-19, particularly among individuals with underlying comorbidities. Patients with pre-existing conditions like diabetes mellitus (DM) are disproportionately affected, facing heightened risks of both disease exacerbation and the onset of new complications. Notably, the convergence of advanced age and DM has been consistently associated with poor COVID-19 outcomes. However, the long-term metabolic consequences of SARS-CoV-2 infection, especially its role in disrupting glucose homeostasis and potentially triggering or worsening DM, remain incompletely understood. This review synthesizes current clinical and experimental findings to clarify the bidirectional relationship between COVID-19 and diabetes. We critically examine literature reporting deterioration of glycemic control, onset of hyperglycemia in previously non-diabetic individuals, and worsening of metabolic parameters in diabetic patients after infection. Furthermore, we explore proposed mechanistic pathways, including pancreatic β-cell dysfunction, systemic inflammation, and immune-mediated damage, that may underpin the development or progression of DM in the post-COVID setting. Collectively, this work underscores the urgent need for continued research and clinical vigilance in managing metabolic health in COVID-19 survivors. Full article

Type 2 diabetes mellitus (T2DM) is a common metabolic disorder characterized by insulin resistance and pancreatic β-cell dysfunction. Emerging evidence indicates that gut microbiota dysbiosis may contribute to the development of T2DM. Individuals with T2DM exhibit notable changes in gut microbiota composition, including shifts in the balance between Firmicutes and Bacteroidetes, a reduction in butyrate-producing bacteria, and an increase in opportunistic pathogens. Gut microbiota-derived metabolites—such as short-chain fatty acids, bile acids, and amino acids—have been implicated in the pathogenesis of T2DM, highlighting the critical role of host-microbe interactions. In this overview, we discuss the gut microbiota dysbiosis associated with T2DM and explore the molecular links between microbiota-derived metabolites and the pathogenesis of diseases. Additionally, we explore potential therapeutic strategies, including probiotics and dietary interventions, to modulate the gut microbiota and its metabolites, providing insights for future clinical research and the development of novel treatments for T2DM. Full article

Background/Objectives: Intrauterine growth restriction (IUGR) is associated with enhanced inflammatory activity, poor skeletal muscle glucose metabolism, and pancreatic β cell dysfunction that persist in offspring. We hypothesized that targeting heightened inflammation in IUGR-born neonatal lambs by supplementing anti-inflammatory ω-3 polyunsaturated fatty acids (ω-3 PUFAs) would improve metabolic outcomes. Methods: Maternal heat stress was used to produce IUGR lambs, which received daily oral boluses of ω-3 PUFA Ca²⁺ salts or placebo for 30 days. Results: Greater circulating TNFα and semitendinosus IL6R in IUGR lambs were fully resolved by ω-3 PUFA, and impaired glucose-stimulated insulin secretion, muscle glucose oxidation, and hypertension were partially rescued. Impaired glucose oxidation by IUGR muscle coincided with a greater glycogen content that was completely reversed by ω-3 PUFA and greater lactate production that was partially reversed. Ex vivo O₂ consumption was increased in IUGR muscle, indicating compensatory lipid oxidation. This too was alleviated by ω-3 PUFA. Conversely, ω-3 PUFA had little effect on IUGR-induced changes in lipid flux and hematology parameters, did not resolve greater muscle TNFR1, and further reduced muscle β2-adrenoceptor content. Conclusions: These findings show that targeting elevated inflammatory activity in IUGR-born lambs in the early neonatal period improved metabolic outcomes, particularly muscle glucose metabolism and β cell function. Full article

Neutrophils are increasingly recognized as key contributors to the pathogenesis of Type 1 Diabetes (T1D), yet their precise mechanistic role in disease onset and progression remains incompletely understood. While these innate immune cells reside in pancreatic tissue and support tissue homeostasis under physiological conditions, they can also drive tissue damage by triggering innate immune responses and modulating inflammation. Within the inflammatory milieu, neutrophils establish complex, bidirectional interactions with various immune cells, including macrophages, dendritic cells, natural killer cells, and lymphocytes. Once activated, they may enhance the innate immune response through direct or indirect crosstalk with immune cells, antigen presentation, and β-cell destruction or dysfunction. These mechanisms underscore the multifaceted and dynamic role of neutrophils in T1D, shaped by their intricate immunological interactions. Further research into the diverse functional capabilities of neutrophils is crucial for uncovering novel aspects of their involvement in T1D, potentially revealing new therapeutic targets to modulate disease progression. Full article

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy, often associated with new-onset diabetes. The relationship between PDAC and diabetes, particularly type 3c diabetes, remains poorly understood. This study investigates whether PDAC-associated diabetes represents a distinct subtype by integrating transcriptomic and histological analyses. Whole-tumour RNA sequencing data from The Cancer Genome Atlas (TCGA) were analysed to compare gene expression profiles between PDAC patients with and without diabetes. Cell-type Identification By Estimating Relative Subsets Of RNA Transcripts (CIBERSORT) deconvolution was employed to assess immune cell populations. Histopathological evaluations of pancreatic tissues were conducted to assess fibrosis and islet morphology. Histological analysis revealed perivascular fibrosis and islet basement membrane thickening in both PDAC cohorts. Transcriptomic data indicated significant downregulation of islet hormone genes insulin (INS) and glucagon (GCG) but not somatostatin (SST) in PDAC-associated diabetes, consistent with a type 3c diabetes phenotype. Contrary to previous reports, no distinct immunogenic signature was identified in PDAC with diabetes, as key immune checkpoint genes (Programmed Cell Death Protein 1 (PDCD1), Cytotoxic T-Lymphocyte Associated Protein 4 (CTLA4), Programmed Death-Ligand 1(PD-L1)) were not differentially expressed. The findings suggest that PDAC-associated diabetes arises through neoplastic alterations in islet physiology rather than immune-mediated mechanisms. The observed reductions in endocrine markers reinforce the concept of PDAC-driven β-cell dysfunction as a potential early indicator of malignancy. Given the poor response of PDAC to PD-L1 checkpoint inhibitors, further research is needed to elucidate alternative therapeutic strategies targeting tumour–islet interactions. Full article

GABA (γ-Aminobutyric Acid), a well-established inhibitory neurotransmitter in the central nervous system, has garnered considerable interest for its potential role in diabetes management, particularly due to its presence in pancreatic islets. This review aims to explore the therapeutic role of GABA in diabetes management and its potential mechanisms for antidiabetic effects. Relevant studies were searched across databases such as PubMed and ScienceDirect, applying strict eligibility criteria focused on GABA administration methods and diabetic models. The collective results showed that the administration of GABA in diabetic models resulted in remarkable enhancements in glucose and insulin homeostasis, favorable modifications in lipid profiles, and amelioration of dysfunctions across neural, hepatic, renal, and cardiac systems. The findings from the literature demonstrated that GABAergic signaling within pancreatic tissues can significantly contribute to the stimulation of β cell proliferation through the facilitation of a sustained trans-differentiation process, wherein glucagon-secreting α cells are converted into insulin-secreting β-like cells. In addition, activated GABAergic signaling can trigger the initiation of the PI3K/AKT signaling pathway within pancreatic tissues, leading to improved insulin signaling and maintained glucose homeostasis. GABAergic signaling can further function within hepatic tissues, promoting inhibitory effects on the expression of genes related to gluconeogenesis and lipogenesis. Moreover, GABA may enhance gut microbiota diversity by attenuating gut inflammation, attributable to its anti-inflammatory and immunomodulatory properties. Furthermore, the neuroprotective effects of GABA play a significant role in ameliorating neural disorders associated with diabetes by facilitating a substantial reduction in neuronal apoptosis. In conclusion, GABA emerges as a promising candidate for an antidiabetic agent; however, further research is highly encouraged to develop a rigorously designed framework that comprehensively identifies and optimizes the appropriate dosages and intervention methods for effectively managing and combating diabetes. Full article

Pancreatic β-cells rely on a delicate balance between the endoplasmic reticulum (ER) and mitochondria to maintain sufficient insulin stores for the regulation of whole animal glucose homeostasis. The ER supports proinsulin maturation through oxidative protein folding, while mitochondria supply the energy and redox buffering that maintain ER proteostasis. In the development of Type 2 diabetes (T2D), the progressive decline of β-cell function is closely linked to disruptions in ER-mitochondrial communication. Mitochondrial dysfunction is a well-established driver of β-cell failure, whereas the downstream consequences for ER redox homeostasis have only recently emerged. This interdependence of ER-mitochondrial functions suggests that an imbalance is both a cause and consequence of metabolic dysfunction. In this review, we discuss the regulatory mechanisms of ER redox control and requirements for mitochondrial function. In addition, we describe how ER redox imbalances may trigger mitochondrial dysfunction in a vicious feed forward cycle that accelerates β-cell dysfunction and T2D onset. Full article

Gestational diabetes mellitus (GDM) is characterized by an inadequate pancreatic β-cell response to pregnancy-induced insulin resistance, resulting in hyperglycemia. The pathophysiology involves reduced incretin hormone secretion and signaling, specifically decreased glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), impairing insulinotropic effects. Pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), impair insulin receptor substrate-1 (IRS-1) phosphorylation, disrupting insulin-mediated glucose uptake. β-cell dysfunction in GDM is associated with decreased pancreatic duodenal homeobox 1 (PDX1) expression, increased endoplasmic reticulum stress markers (CHOP, GRP78), and mitochondrial dysfunction leading to impaired ATP production and reduced glucose-stimulated insulin secretion. Excessive gestational weight gain exacerbates insulin resistance through hyperleptinemia, which downregulates insulin receptor expression via JAK/STAT signaling. Additionally, hypoadiponectinemia decreases AMP-activated protein kinase (AMPK) activation in skeletal muscle, impairing GLUT4 translocation. Placental hormones such as human placental lactogen (hPL) induce lipolysis, increasing circulating free fatty acids which activate protein kinase C, inhibiting insulin signaling. Placental 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) overactivity elevates cortisol levels, which activate glucocorticoid receptors to further reduce insulin sensitivity. GDM diagnostic thresholds (≥92 mg/dL fasting, ≥153 mg/dL post-load) are lower than type 2 diabetes to prevent fetal hyperinsulinemia and macrosomia. Management strategies focus on lifestyle modifications, including dietary carbohydrate restriction and exercise. Pharmacological interventions, such as insulin or metformin, aim to restore AMPK signaling and reduce hepatic glucose output. Emerging therapies, such as glucagon-like peptide-1 receptor (GLP-1R) agonists, show potential in improving glycemic control and reducing inflammation. A mechanistic understanding of GDM pathophysiology is essential for developing targeted therapeutic strategies to prevent both adverse pregnancy outcomes and the progression to overt diabetes in affected women. Full article

Diabetes mellitus (DM) is a chronic metabolic disorder and one of the most significant global health burdens worldwide. Key pathophysiological mechanisms underlying its onset and associated complications include hyperglycemia-related stresses, such as oxidative stress and endoplasmic reticulum stress (ER stress). Long non-coding RNAs (lncRNAs), defined as RNA transcripts longer than 200 nucleotides and lacking protein-coding capacity, play crucial roles in various biological processes and have emerged as crucial regulators in the pathogenesis of diabetes. This review provides a comprehensive overview of lncRNA biogenesis and its functional roles, emphasizing recent findings that link stress-related lncRNAs to diabetic pathology and complications. Also, we discuss how lncRNAs influence diabetes and its complications by modulating pathways involved in cell death, proliferation, inflammation, and fibrosis, which contribute to pancreatic β cell dysfunction, insulin resistance, diabetic nephropathy, and retinopathy. By analyzing current research, we aim to enhance understanding of lncRNA involvement in diabetes while identifying potential therapeutic targets and guiding future research directions to elucidate the complex mechanisms underlying this pervasive condition. Full article

Gracilaria species, a widely distributed genus of red macroalgae, have gathered significant attention for their diverse medical applications attributable to their bioactive sulphated polysaccharides (SPs). This review examines the global narrative of various Gracilaria SP applications in terms of their therapeutic potential and mechanistic insights into the use of these SPs against a range of medical conditions, including cancer, inflammation, neurodegenerative disorders, diabetes, and immune dysfunctions. SPs extracted from G. lemaneiformis and G. fisheri have demonstrated potent anti-tumour activities by inducing apoptosis through various mechanisms, including the upregulation of CD8⁺ T cells and IL-2, inhibition of EGFR/MAPK/ERK signalling pathways, and activation of the Fas/FasL pathway. Selenium nanoparticles (SeNPs) conjugated with SPs further enhanced the targeted delivery and efficacy of these SPs against glioblastoma by the downregulation of ROS followed by the activation of p53, MAPK, and AKT pathways. The anti-inflammatory properties of SPs are evidenced by key suppressive inflammatory markers like NO, TNF-α, IL-1β, and IL-6 in mutant rodent models. SPs from G. cornea and G. birdiae effectively reduce neutrophil migration and vascular permeability, offering potential treatments for acute inflammation and conditions such as colitis by modulating pathways involving COX-2 and NF-κB. Neuroprotective effects by SPs (from G. cornea and G. gracili) studied in 6-OHDA-induced rats, which mitigate oxidative stress and enhance neuronal cell viability, facilitate the management of neurodegenerative diseases like Parkinson’s and Alzheimer’s. Regarding the hypoglycaemic effect, SPs from G. lemaneiformis exhibit a glucose-modulating response by improving insulin regulation, inhibiting α-amylase activity, repairing pancreatic β-cells, and modulating lipid metabolism. Moreover, immunomodulatory activities of Gracilaria-derived SPs include the stimulation of macrophages, T-cell proliferation, and cytokine production, underscoring their potential as functional food and immunotherapeutic agents. Recently, Gracilaria-derived SPs have been found to modulate gut microbiota, promote SCFA production, and enhance gut microbials, suggesting their potential as prebiotic agents (G. rubra and G. lemaneiformis). This review highlights the multifaceted medical applications of Gracilaria sulphated polysaccharides, providing detailed mechanistic insights and suggesting avenues for future clinical translation and therapeutic innovations. Full article

High-density lipoprotein (HDL) exhibits multiple metabolic protective functions, such as facilitating cellular cholesterol efflux, antioxidant, anti-inflammatory, anti-apoptotic and anti-thrombotic properties, showing antidiabetic and renoprotective potential. Diabetic kidney disease (DKD) is considered to be associated with high-density lipoprotein cholesterol (HDL-C). The hyperglycemic environment, non-enzymatic glycosylation, carbamylation, oxidative stress and systemic inflammation can cause changes in the quantity and quality of HDL, resulting in reduced HDL levels and abnormal function. Dysfunctional HDL can also have a negative impact on pancreatic β cells and kidney cells, leading to the progression of DKD. Based on these findings, new HDL-related DKD risk predictors have gradually been proposed. Interventions aiming to improve HDL levels and function, such as infusion of recombinant HDL (rHDL) or lipid-poor apolipoprotein A-I (apoA-I), can significantly improve glycemic control and also show renal protective effects. However, recent studies have revealed a U-shaped relationship between HDL-C levels and DKD, and the loss of protective properties of high levels of HDL may be related to changes in composition and the deposition of dysfunctional particles that exacerbate damage. Further research is needed to fully elucidate the complex role of HDL in DKD. Given the important role of HDL in metabolic health, developing HDL-based therapies that augment HDL function, rather than simply increasing its level, is a critical step in managing the development and progression of DKD. Full article

Consuming a “modern” Western diet and overnutrition may increase insulin secretion. Additionally, nutrition-mediated hyperinsulinemia is a major driver of ectopic fat deposition. The global prevalence of metabolic syndrome is high and growing. Within this context, people with congenital lipodystrophy often experience a severe form of metabolic syndrome. Evidence is increasingly supporting that subtle partial lipodystrophy plays an important role in the development of metabolic syndrome in the general population. In individuals in the general population with subtle partial lipodystrophy, as well as in those with congenital lipodystrophy, the subcutaneous adipose tissues are unable to accommodate surplus energy intake. In both conditions, (excess) fat is directed toward the liver, pancreas, and muscles, where it is deposited as ectopic fat, as this fat can no longer be stored in the “safe” subcutaneous fat depots. Ectopic fat depositions cause insulin resistance in the liver and muscles, as well as β-cell dysfunction in the pancreas. Support of a direct pathological role of ectopic fat deposition in this condition is further provided by the rapid normalization of hepatic insulin sensitivity and improvement in pancreatic β-cell function after marked reductions in ectopic fat depositions. Thus, ectopic fat deposition in the liver, pancreas, and muscles may play a causal role in the pathogenesis of metabolic syndrome even in the general population. As such, the prevention of ectopic fat deposition may reduce the risk of metabolic syndrome and mitigate its effects. Full article