Pancreatic islets

Within the islets of Langerhans, beta cells orchestrate synchronized insulin secretion, a pivotal aspect of metabolic homeostasis. Despite the inherent heterogeneity and multimodal activity of individual cells, intercellular coupling acts as a homogenizing force, enabling coordinated responses through the propagation of intercellular waves. Disruptions in this coordination are implicated in irregular insulin secretion, a hallmark of diabetes. Recently, innovative approaches, such as integrating multicellular calcium imaging with network analysis, have emerged for a quantitative assessment of the cellular activity in islets...

Endogenous retroviruses (ERVs) are involved in autoimmune diseases such as type 1 diabetes (T1D). ERV gene products homologous to murine leukemia retroviruses are expressed in the pancreatic islets of NOD mice, a model of T1D. One ERV gene, Gag, with partial or complete open reading frames (ORFs), is detected in the islets, and it contains many sequence variants. An amplicon deep sequencing analysis was established by targeting a conserved region within the Gag gene to compare NOD with T1D-resistant mice or different ages of prediabetic NOD mice...

In recent years, the potential of stem cells (SCs) to differentiate into various types of cells, including β-cells, has led to a significant boost in development. The efficiency of this differentiation process and the functionality of the cells post-transplantation are crucial factors for the success of stem cell therapy in diabetes. Herein, this article reviews the current advances and challenges faced by stem cell differentiation into functional β-cells for diabetes treatment. In vitro, researchers have sought to enhance the differentiation efficiency of functional β-cells by mimicking the normal pancreatic development process, using gene manipulation, pharmacological and culture conditions stimulation, three-dimensional (3D) and organoid culture, or sorting for functional β-cells based on mature islet cell markers...

AIMS/HYPOTHESIS: cGAS (cyclic GMP-AMP synthase) has been implicated in various cellular processes, but its role in β-cell proliferation and diabetes is not fully understood. This study investigates the impact of cGAS on β-cell proliferation, particularly in the context of diabetes. METHODS: Utilizing mouse models, including cGAS and STING (stimulator of interferon genes) knockout mice, we explored the role of cGAS in β-cell function. This involved β-cell-specific cGAS knockout (cGASβKO ) mice, created by breeding cGAS floxed mice with transgenic mice expressing Cre recombinase under the insulin II promoter...

The endocrine pancreas is composed of clusters of cell groups called pancreatic islets. These cells are responsible for the synthesis and secretion of hormones crucial for glycemic homeostasis, such as insulin and glucagon. Therefore, these cells were the targets of many studies. One method to study and/or understand endocrine pancreatic physiology is the isolation of these islets and stimulation of hormone production using different concentrations of glucose, agonists, and/or antagonists of specific secretagogues and mimicking the stimulation of hormonal synthesis and secretion...

BACKGROUND: Islet transplantation is an effective treatment for diabetes or even its complications. Aim of this study is to investigate efficacy of biomaterial treated islet transplantation on treating diabetic nephropathy. METHODS: Male rats were randomly divided into 6 groups; Control, diabetic control, diabetic transplanted with untreated islets, with platelet rich plasma treated islets, with pancreatic islets homogenate treated islets, or with these biomaterials combination treated islets...

The presence of epithelial cells within lymph node parenchyma is typically indicative of a metastatic malignancy. However, there are rare instances in which non-neoplastic epithelial or epithelioid cells may be found within lymph nodes, either due to aberrant embryologic migration, mechanical displacement, or physiological trafficking. These can potentially lead to serious potential diagnostic pitfalls, as when such situations are encountered by surgical pathologists, there is substantial risk of overdiagnosing these as metastatic malignancy...

The purpose of this review was to analyze the scientific literature on exocrine pancreatic insufficiency (EPI) in dogs and cats and our own research on porcine model to compare animal- and microbial-derived enzymes in the treatment of animals with this disease. Clinical signs of EPI occur when more than 85% of the pancreatic parenchyma is non-functional. EPI can be a consequence of various diseases. The insufficient activity or deficiency of pancreatic enzymes leads to impaired digestion and absorption, and consequently, to malnutrition...

ETHNOPHARMACOLOGICAL RELEVANCE: Schisandra sphenanthera (Schisandra sphenanthera Rehd. et Wils.) is the dried mature fruit of Schisandra sphenanthera, a plant in the Magnoliaceae family. It was used in the treatment of diabetes mellitus in the Jade Fluid Decoction and the Xiaoke pills, which were recorded in ancient books. However, its mechanism of action in the treatment of type 2 diabetes mellitus (T2DM) was unclear and needs further study. AIM OF THE STUDY: This research aimed to investigate the chemical composition and lignan content of Schisandra sphenanthera petroleum ether parts (SPEP) and to evaluate the effects of SPEP on sweet taste receptors (STRs) and intestinal flora in rats on a high-fat diet (HFD)...

Cadmium (Cd) is a heavy metal that acts as endocrine disrupting chemical (EDC). Few studies have investigated the effects of Cd exposure on metabolic dysfunctions, such as type 1 and 2 diabetes mellitus (T1DM and T2DM). Thus, we assessed whether subacute Cd exposure at occupational levels causes abnormalities in white adipose tissue (WAT), liver, pancreas, and skeletal muscle. We administered cadmium chloride (CdCl2 ) (100 ppm in drinking water for 30 days) to female rats and evaluated Cd levels in serum and metabolic organs, morphophysiology, inflammation, oxidative stress, fibrosis, and gene expression...

Preclinical and clinical studies suggest that lipid-induced hepatic insulin resistance is a primary defect that predisposes to dysfunction in pancreatic islets, implicating a perturbed liver-pancreas axis underlying the comorbidity of T2DM and MASLD. To investigate this hypothesis, we developed a human biomimetic microphysiological system (MPS) coupling our vascularized liver acinus MPS (vLAMPS) with primary islets on a chip (PANIS) enabling MASLD progression and islet dysfunction to be quantitatively assessed...

OBJECTIVES: Diabetes secondary to chronic pancreatitis (CP) presents clinical challenges due to insulin secretory defects and associated metabolic alterations. Owing to lack of molecular understanding, no pharmacotherapies to treat insulin secretory defects have been approved to date. We aimed to delineate the molecular mechanism of β-cell dysfunction in CP. METHODS: Transcriptomic analysis was conducted to identify endocrine specific receptor expression in mice and human CP on microarray...

N6 -methyladenine (m6 A) and 5-methylcytosine (m5 C) are two common forms of RNA methylation that play an important role in the epigenetics of type 2 diabetes mellitus (T2DM). One type of cell death, ferroptosis, has been implicated in islet β-cell damage in T2DM. Notably, RNA methylation, an upstream regulatory mechanism of mRNAs, can regulate the expression of ferroptosis signaling molecules, thereby affecting cell proliferation and death. Here, we found that the ferroptosis signaling pathway was activated in pancreas of T2DM rats, followed by significant changes in m6 A/m5 C modification regulatory molecules...

Most pancreatic islets are destroyed immediately after intraportal transplantation by an instant blood-mediated inflammatory reaction (IBMIR) generated through activation of coagulation, complement, and proinflammatory pathways. Thus, effective mitigation of IBMIR may be contingent on the combined use of agents targeting these pathways for modulation. CD47 and thrombomodulin (TM) are two molecules with distinct functions in regulating coagulation and proinflammatory responses. We previously reported that the islet surface can be modified with biotin for transient display of novel forms of these two molecules chimeric with streptavidin (SA), that is, thrombomodulin chimeric with SA (SA-TM) and CD47 chimeric with SA (SA-CD47), as single agents with improved engraftment following intraportal transplantation...

Total pancreatectomy with islet autotransplantation (TPIAT) is an established and effective treatment modality for patients diagnosed with intractable chronic pancreatitis (CP) and recurrent acute pancreatitis (RAP). TPIAT primarily aims to manage debilitating pain leading to impaired quality of life among patients with CP or RAP, which can be successfully managed with medical, endoscopic, or surgical interventions. TPIAT is significantly successful in relieving pain associated with CP and improving health-related quality of life outcomes...

OBJECTIVE: The contribution of the mitochondrial electron transfer system to insulin secretion involves more than just energy provision. We identified a small RNA fragment (mt-tRF-LeuTAA ) derived from the cleavage of a mitochondrially-encoded tRNA that is conserved between mice and humans. The role of mitochondrially-encoded tRNA-derived fragments remains unknown. This study aimed to characterize the impact of mt-tRF-LeuTAA , on mitochondrial metabolism and pancreatic islet functions...

Cellular composition and anatomical organization influence normal and aberrant organ functions. Emerging spatial single-cell proteomic assays such as Image Mass Cytometry (IMC) and Co-Detection by Indexing (CODEX) have facilitated the study of cellular composition and organization by enabling high-throughput measurement of cells and their localization directly in intact tissues. However, annotation of cell types and quantification of their relative localization in tissues remain challenging. To address these unmet needs for atlas-scale datasets like Human Pancreas Analysis Program (HPAP), we develop AnnoSpat (Annotator and Spatial Pattern Finder) that uses neural network and point process algorithms to automatically identify cell types and quantify cell-cell proximity relationships...

AIM: To investigate the effects of adenosine kinase (ADK), a key enzyme in determining intracellular adenosine levels, on β cells, and their underlying mechanism. METHODS: Genetic animal models and transgenic immortalized cells were applied to study the effect of ADK on islet beta-cell proliferation and function. The beta-cell mass and response to glucose were measured in vivo using mice with beta-cell-specific ADK overexpression, and in vitro using ADK-overexpressed immortalized beta-cell...

Cancer remains a worldwide cause of morbidity and mortality. Investigational research efforts have included the administration of tumor-derived extracts to healthy animals. Having previously demonstrated that the administration of non-transmissible, human cancer-derived homogenates induced malignant tumors in mice, here, we examined the consequences of administering 50 or 100 µg of protein of crude homogenates from mammary carcinoma, pancreatic adenocarcinoma, and melanoma samples in 6 inoculations per week during 2 months...

Pancreatic islets, particularly insulin-producing β-cells, are central regulators of glucose homeostasis capable of responding to a variety of metabolic stressors. Pregnancy is a unique physiological stressor, necessitating the islets to adapt to the complex interplay of maternal and fetal-placental factors influencing the metabolic milieu. In this review we highlight studies defining gestational adaptation mechanisms within maternal islets and emerging studies revealing islet adaptations during the early postpartum and lactation periods...