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Pancreatic ductal adenocarcinoma (PDAC) is one of the most potent and perilous diseases known, with a median survival rate of 3-5 months due to the combination of only advanced stage diagnosis and ineffective therapeutic options. Metformin (1,1-Dimethylbiguanide hydrochloride), the leading drug used for type 2 diabetes mellitus, emerges as a potential therapy for PDAC and other human cancers. Metformin exerts its anticancer action via a variety of adenosine monophosphate (AMP)-activated protein kinase (AMPK)- dependent and/or AMPK-independent mechanisms. We present data here showing that metformin downregulated pancreatic transcription factor pancreatic duodenal homeobox-1 (PDX-1), suggesting a potential novel mechanism by which metformin exerts its anticancer action. Metformin inhibited PDX-1 expression at both protein and mRNA levels and PDX-1 transactivity as well in PDAC cells. Extracellular signal-regulated kinase (ERK) was identified as a PDX-1-interacting protein by antibody array screening in GFP-PDX-1 stable HEK293 cells. Co-transfection of ERK1 with PDX-1 resulted in an enhanced PDX-1 expression in HEK293 cells in a dose-dependent manner. Immunoprecipitation/Western blotting analysis confirmed the ERK-PDX-1 interaction in PANC-1 cells stimulated by epidermal growth factor (EGF). EGF induced an enhanced PDX-1 expression in PANC-1 cells and this stimulation was inhibited by MEK inhibitor PD0325901. Metformin inhibited EGF-stimulated PDX-1 expression with an accompanied inhibition of ERK kinase activation in PANC- 1 cells. Taken together, our studies show that PDX-1 is a potential novel target for metformin in PDAC cells and that metformin may exert its anticancer action in PDAC by down-regulating PDX-1 via a mechanism involving inhibition of ERK signaling.

Objectives: The effects of glucocorticoid during culture on human islet cells have been controversial. Exendin-4 (EX) enhances the insulin secretion and significantly improves clinical outcomes in islet cell transplantation. In this study, we examined the effects of glucocorticoids and EX on human islet cells during pretransplant culture.

The aim of the study was to determine age- and race-related, and overall incidence rates of insulin-requiring diabetes in adults in the US military.Electronic records for admissions to US military and Tricare hospitals during 1990–2005 and visits to military clinics during 2000–2005 were identified using the Career History Archival Medical and Personnel System at the Naval Health Research Center, San Diego, CA, USA. Population data were obtained from the Defense Manpower Data Center and Defense Medical Epidemiology Database.In men there were 2,918 new cases of insulin-requiring diabetes in 20,427,038 person-years at ages 18–44 years (median age 28 years) for a total age-adjusted incidence rate of 17.5 per 100,000 person-years (95% CI 16.4–18.6). Incidence rates were twice as high in black men as in white men (31.5 vs 14.5 per 100,000, p

Cell-cell and cell-matrix interactions play a critical role in tissue morphogenesis and in homeostasis of adult tissues. The integrin family of adhesion receptors regulates cellular interactions with the extracellular matrix, which provides three-dimensional information for tissue organization. It is currently thought that pancreatic islet cells develop from undifferentiated progenitors residing within the ductal epithelium of the fetal pancreas. This process involves cell budding from the duct, migration into the surrounding mesenchyme, differentiation, and clustering into the highly organized islet of Langerhans. Here we report that alpha(v)beta(3) and alpha(v)beta(5), two integrins known to coordinate epithelial cell adhesion and movement, are expressed in pancreatic ductal cells and clusters of undifferentiated cells emerging from the ductal epithelium. We show that expression and function of alpha(v)beta(3) and alpha(v)beta(5) integrins are developmentally regulated during pancreatic islet ontogeny, and mediate adhesion and migration of putative endocrine progenitor cells both in vitro and in vivo in a model of pancreatic islet development. Moreover, we demonstrate the expression of fibronectin and collagen IV in the basal membrane of pancreatic ducts and of cell clusters budding from the ductal epithelium. Conversely, expression of vitronectin marks a population of epithelial cells adjacent to, or emerging from, pancreatic ducts. Thus, these data provide the first evidence for the contribution of integrins alpha(v)beta(3) and alpha(v)beta(5) and their ligands to morphogenetic events in the human endocrine pancreas.

Omega-3 polyunsaturated fatty acids (PUFA) have demonstrated anti-inflammatory properties, while Omega-6 have pro-inflammatory effects, and the balance between the two is an important aspect of healthy nutrition. Over the last 30 years, however, the Western diet has shifted largely from Omega-3 to Omega-6 consumption. Uncontrolled aberrant and chronic inflammation is a leading component of many common diseases, including arthritis, cardiovascular diseases, neurodegenerative diseases, cancer, obesity, autoimmune diseases, and infective diseases. Eicosanoids derived from Omega-6 participate in the inflammatory process, while Omega-3 PUFA have the opposite effect. Many favorable effects of Omega-3 are believed to result from their anti-inflammatory properties, but eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) also have inhibitory effects on immune cells and reduce proinflammatory cytokine release. All these mechanisms can be beneficial in autoimmunity. No effective preventions or definite cures for autoimmune diseases are yet known because pathophysiology is also unclear. Omega-3 fatty acid supplementation is associated with a significant reduction in disease activity in several autoimmune diseases, like type 1 diabetes (T1D), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and multiple sclerosis (MS). Studies of viral diseases, including COVID-19, show improvement in symptom severity, recovery prognosis, and probability of survival with the use of Omega-3. Finally, the evidence of the beneficial effect of Omega-3 on metabolic diseases associated with aging is persuasive; various studies have demonstrated that their consumption improves lipids, fatty liver disease, obesity, cognitive function, and cardiovascular complications of chronic kidney disease (CKD). Omega-3 PUFA have also been shown to support an anti-inflammatory effect in older age and to have favorable effects on age-related disease's complications, frailty, and mortality. A healthy Omega-6/3 PUFA ratio should be targeted for the modulation of low-grade inflammation, as well as for the prevention of immune dysregulation and complications of uncontrolled inflammation triggered by infections, development, and progression of autoimmune disorders, and the consequences of oxidative stress due to aging. There is still a need for randomized clinical studies to validate current evidence supporting supplementation with correct doses of Omega-3 PUFA in autoimmune and chronic disease prevention. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) is defined as a relapsing and remitting condition characterized by chronic inflammation at different sites in the gastrointestinal tract. Crohn's disease (CD) and ulcerative colitis (UC) represents the two major forms of IBD. Even though IBD pathophysiology is still not fully understood, genetic factors, environmental factors, dysregulation of both innate and adaptive immune responses, alterations in gut microbiota composition, excessive consumption of saturated fats and cumulative antibiotic exposure have all been suggested to play a role in the development of this condition. Amongst the environmental factors, vitamin D deficiency has been suggested to participate in IBD pathophysiology. Indeed, vitamin D exerts several pleiotropic effects beyond its well-established regulation of bone and calcium homeostasis, including anti-infective, anti- inflammatory and immunomodulatory effects as well as maintenance of gastrointestinal barrier integrity and beneficial gut microbiota composition. In this narrative review, we discuss the role of vitamin D deficiency in IBD pathophysiology as well as the potential therapeutic use of vitamin D for the management of IBD. [ABSTRACT FROM AUTHOR]