72 Clinical Trials for Various Conditions
Fasting hyperglycemia contributes disproportionately to nonenzymatic glycosylation and the microvascular complications of type 2 diabetes. However, little is known about the regulation of glucose concentrations in the fasting state relative to what is known about the postprandial state. The proposed experiment is part of a series of experiments designed to establish how glucagon and insulin interact with their receptors to control fasting glucose in health and in prediabetes.
This is a randomized, parallel group, double-blind Phase 2 study with a 52-week blinded extension evaluating the safety and efficacy of 3 dose levels of frexalimab in comparison with placebo in participants with newly diagnosed T1D on insulin treatment. Study details include: Screening period: at least 3 weeks and up to 5 weeks Double-blind treatment period (104 weeks): * Main treatment period: 52 weeks * Blinded extension: 52 weeks Safety follow-up: up to 26 weeks The treatment duration will be up to 104 weeks, the total study duration will be up to 135 weeks.
The goal of this study is to understand how exogenous kisspeptin affects metabolism by evaluating responses to an hyperglycemic clamp
The goal of this study is to understand how exogenous kisspeptin affects metabolism by evaluating responses to an oral glucose tolerance test
This study utilizes infusions of kisspeptin in healthy women to isolate the impact of kisspeptin on beta-cell responsivity assessed by the mixed meal tolerance test.
The GLP-1 receptor (GLP1R) gene is found on the beta cells of the pancreas. Its role is in the control of blood sugar level by enhancing insulin secretion from the pancreas after eating a meal. The purpose of this research study is to evaluate the role of GLP1R in the response to elevated glucagon concentrations.
The purpose of this research is to study the effects of 1,25(OH)2 D3 (a prescription form of active Vitamin D) on muscle strength and insulin secretion by the pancreas and glucose utilization by skeletal muscle.
Researchers are trying to determine how changes in fasting glucose and free fatty acids (products released from fat) affect insulin secretion.
The hypothesis for this study is that pancreas lipid will be more closely associated with first-phase beta-cell response in African-Americans than in European-Americans, both at baseline and in response to treatment. The investigators will determine whether race influences the association of pancreas lipid with beta-cell function.The proposed research builds upon the investigators preliminary observations in non-diabetic adults that reduction in dietary glycemic load, in the absence of weight loss, selectively reduces visceral adipose tissue and ectopic lipid, and is associated with improvements in insulin sensitivity and beta-cell function. No study has attempted to test the hypothesis that selective reduction in pancreatic lipid with a simple change in diet composition, in the absence of energy restriction, will lead to the recovery of beta-cell function in patients with early Type 2 Diabetes (T2D). The investigators hypothesize that participants following a Low Glycemic Diet will show a greater decrease in pancreas lipid. Specifically, the investigators will be the first to demonstrate that a weight-maintaining low-glycemic diet improves glucose tolerance by increasing first-phase insulin secretion. Results may be particularly relevant to African-Americans who are at greater risk for T2D.
AIM2: The purpose of Aim-2 of this study is to determine the role of basal GLP-1 action on the beta-cell response to insulin resistance. Healthy subjects will have fasting GLP-1 action determined with GLP-1r blockade before and after induction of experimental insulin resistance. The investigators hypothesize that fasting GLP-1 action will increase to compensate for experimental insulin resistance. AIM3: The purpose of Aim-3 of this study is to determine the role of basal GLP-1 action on fasting glucose regulation in lean, obese, pre-diabetic and type 2 diabetic (T2DM) subjects. A cross sectional study of age-matched subjects across the spectrum of glucose tolerance will be used to test the hypothesis that fasting GLP-1 action increases as beta-cell function declines.
This is a clinical study of a drug named dopamine and how it affects our bodies ability to make and secrete insulin. Insulin is a hormone made in the pancreas that helps our body regulate sugar levels. We think that this drug decreases the amount of insulin our body makes and causes our sugar levels to be high. When you are critically ill there can be many adverse effects if you have sugar levels that are too high.
The purpose of this study is to assess changes from baseline in insulin sensitivity, hepatic fat content and beta cell function after approximately 24-25 weeks of treatment with canagliflozin compared to placebo in participants with type 2 diabetes mellitus (T2DM) with inadequate glycemic (blood sugar) control on metformin monotherapy or on combination therapy with metformin and a dipeptidyl peptidase-4 (DPP-4) inhibitor.
Glucose-dependent insulinotropic polypeptide (GIP) is a hormone produced in the intestine. It is released immediately after meal ingestion and increases insulin release. This, in turn, helps reduce blood glucose levels. This circuit does not work properly in humans with type 2 diabetes mellitus (T2DM). We have previously shown that a peptide called xenin-25 can amplify the effects of GIP on insulin secretion in humans. However, xenin-25 no longer does this when humans develop T2DM. Thus, it is important to understand how xenin-25 works in humans without T2DM so we know why it does not work in humans with T2DM. Acetylcholine is molecule produced by specific types of nerves. The effects of acetylcholine can be blocked by a drug called atropine. We have previously shown in mice that atropine prevents the ability of xenin-25 to increase the effects of GIP on insulin release. The purpose of this clinical trial is to determine if atropine also blocks the effects of xenin-25 in humans without T2DM. If it does, then impaired acetylcholine signaling may be one of the reasons humans develop T2DM and it could be possible to develop drugs that bypass this defect and increase insulin release in humans with T2DM.
Glucose-dependent Insulinotropic Polypeptide (GIP) and xenin-25 are peptide hormones produced/released from your intestines and help regulate blood sugar levels after you eat. We have previously performed studies in humans that measured the effects of xenin-25 and GIP (alone and together) on blood sugar levels. One study was conducted with an intravenous infusion of glucose but without ingestion of a meal. In this study, xenin-25 increased the effects of GIP on insulin secretion- but only in humans without type 2 diabetes mellitus (T2DM). A second study was conducted in conjunction with ingestion of a meal. In this study, xenin-25 reduced blood glucose levels by delaying gastric emptying and this effect was similar in humans with and without T2DM. A variety of studies that we have performed suggest that xenin-25 works by activating nerves. A specific nerve called the vagus nerve plays an important role in regulating insulin secretion. This study will determine if the vagus nerve (which was disrupted if you had a vagotomy) is needed for the effects of xenin-25 on insulin secretion and/or gastric emptying.
The purpose of this study is to explore the mechanisms of metabolic control in monogenic diabetes patients treated with sulfonylurea medications.
The optimal insulin therapy in T2DM is controversial and its impact on nonalcoholic fatty liver disease (NAFLD) has not been systematically studied before, and in particular, never when using the new insulin formulations detemir (Levemir®) or aspart (Novolog®). This study is to determine the effect on hepatic steatosis and insulin secretion/action of lowering the fasting plasma glucose (FPG) to target with once daily basal insulin detemir alone or combining insulin detemir with premeal insulin aspart in patients with uncontrolled type 2 diabetes mellitus (T2DM). In the first 3 months the investigators will optimize metabolic control in all patients with intensive basal (bedtime) detemir insulin aiming at a normal fasting plasma glucose. After this treatment period, patients will be randomized in the second 3 months in a 2:1 ratio to insulin detemir or detemir plus aspart. The investigators propose that insulin will improve day-long glycemic control and A1c, reduce hepatic steatosis (NAFLD) (primary endpoint) and insulin secretion/sensitivity being well tolerated while causing minimal weight gain and hypoglycemia (secondary endpoints). The study will allow to assess if there is an additional benefit of adding pre-meal rapid-acting insulin aspart to basal insulin to these endpoints.
RYGB (roux-en-y gastric bypass) has been reported to reverse type 2 diabetes (T2DM) immediately after surgery before any significant weight loss. In addition, a growing number of patients have been recognized with life-threatening hyperinsulinemic hypoglycemia several years following their surgery. While the mechanisms by which RYGB improves glucose metabolism or alters islet cell function in patients after RYGB are not understood, recent studies suggest that increased secretion of GI hormones, primarily glucagon-like peptide 1 (GLP-1), as well as alteration in neural activity may contribute to enhanced insulin secretion in general, and to a greater extent in patients with hypoglycemia. The proposed research is designed to address the role of RYGB on insulin secretion by evaluating the contribution of stimulatory factors (neural and GI hormone) on islet cell function and the islet cell responsiveness to the physiologic stimulatory factors, in RYGB patients with and without hypoglycemia and non-operated controls.
The purpose of this study is to evaluate the effect of zinc supplementation on insulin secretion by genotype of SLC30A8.
An intestinal hormone called Glucose-dependent Insulinotropic Polypeptide (GIP) is released into the blood immediately after ingestion of a meal and plays an important role in regulating blood sugar levels. However, GIP is not active in persons with type 2 diabetes mellitus (T2DM) which is also known as adult onset or non-insulin-dependent diabetes. This study is being conducted to determine whether a hormone called xenin-25 can restore the activity of GIP in persons with T2DM.
The purpose of the study is to assess the relationship between vitamin D status and insulin- glucose dynamics in obese Adolescents. The study is intended to assess the difference in the insulin sensitivity before and after correction of vitamin D deficiency.
Sub-clinical vitamin D deficiency is a commonly unrecognized disorder in obese adolescents. The investigators hypothesize vitamin D deficiency will be highly prevalent in obese adolescents and those who are vitamin D deficient will be more insulin resistant.
The purpose of this study is to examine changes in sugar metabolism that may occur in subjects who have previously had part of their pancreas removed due to a benign lesion.
The purpose of this study is to evaluate the effects of dapagliflozin on insulin sensitivity
The objective of this project is to understand defects in insulin secretion that contribute to abnormal glucose metabolism in patients with diabetes. In particular the effects of signals released from the intestine to stimulate insulin secretion will be tested. Patients with type 2 diabetes will have insulin secretion in response to glucose and intestinal factors before and after insulin treatment to lower their blood glucose. It is expected that the results of this work will provide valuable information for treating diabetic people.
This is a pilot study to examine the prevalence of metabolic risk factors (impaired insulin release and impaired insulin sensitivity) for type 2 diabetes mellitus in children and adults from a population that is at high risk for this disease. We hypothesize that at least one of these pre-diabetic traits will be evident in a large proportion of relatives of known type 2 diabetic children as compared to a control group of subjects without a family history of type 2 diabetes. By isolating these traits, it will be possible to determine the relative contributions of genes and environment to each trait and to identify those at risk for subsequent development of type 2 diabetes by virtue of having one trait. Ultimately, those individuals at risk, especially those with impaired insulin release, would hopefully benefit from intervention to prevent the weight gain that will 'unmask' their underlying pancreatic dysfunction and thus prevent or retard the development of type 2 diabetes.
This grant is to study patients that have received a kidney transplant AND an Islet Cell transplant and to discover how the transplant is functioning. We will seek to have several patients who have had a kidney transplant but do NOT have either type of diabetes. These patients will serve as the "control group" since they will also be on immunosuppressive medications but are not affected by abnormal blood sugars. This will allow investigators to develop an understanding of how these immunosuppressive medications affect glucose metabolism (blood sugar levels) and insulin utilization (how the body uses insulin).
Glucagon is a 30 amino acid peptide hormone that is produced exclusively in alpha-cells of the pancreatic islets. Glucagon binds to a G-protein coupled receptor and activates intracellular signaling by increasing the synthesis of cyclic AMP by adenylate cyclase. The glucagon receptor is most prominently expressed by hepatocytes and the cardinal action of glucagon is to stimulate hepatic glucose output by increasing glycogenolysis and gluconeogenesis. A deep body of literature supports physiologic actions of glucagon to maintain fasting blood glucose and counter-regulate hypoglycemia, and the current view of glucose metabolism is that insulin and glucagon have opposing and mutually balancing effects on glycemia. However, it has long been appreciated that glucagon actually stimulates insulin secretion and islet β-cells express the glucagon receptor and respond to its activation by increasing cAMP. The most potent stimulus for glucagon release is hypoglycemia and both low glucose per sé, as well as sympathetic nervous system activity are potent activators of the alpha-cell. However, glucagon is also stimulated by elevations of circulating amino acids, including after protein containing meals; this setting is one in which the release of glucagon during a period of elevated glycemia could contribute to postprandial insulin secretion. In fact, we have demonstrated that normal mice injected with glucagon while fasting (BG 75 mg/dl) have a prompt rise in blood glucose, whereas mice given glucagon while feeding (BG 150 mg/dl) increase insulin output 3 fold and have a decrease in glycemia. Moreover, in studies with isolated mouse and human islets we have demonstrated that glucagon stimulates insulin release by activating both the glucagon and GLP-1 receptors. This counter-intuitive observation has been reported by several other groups as well as ours. In the studies proposed herein we wish to extend our novel observations to humans. The possibility that glucagon acts in the fed state to promote insulin secretion and glucose disposal would change current views of physiology in both healthy and diabetic persons. Moreover, since one of the more promising area of drug development is the creation of peptides that activate multiple receptors (GLP-1 + glucagon, GLP-1 + GIP + glucagon) the results of our studies have potential implications for therapeutics as well.
This project is designed to advance understanding of the incretin effect in health and disease. This system of gut-islet linkage is essential for normal glucose tolerance, impaired in T2DM, and amenable to therapeutic intervention. However, there are important gaps in understanding incretin function that limit application of this system; this project will address several of these. A secondary, but critical aspect of this research is focus on inter-individual variation in the physiology of the incretin system. This is a novel direction for research in this field and is critical to advancing the concept of individualized medical care in diabetes by establishing whether there is a physiologic basis for predicting the existence of responders and non-responders to incretin therapies. Currently, we have described only Aim 1 from this grant in this protocol registration. While Aim 2 and 3 are described in the grant, Aim 1 will be conducted first and the results from this Aim and / or the publication of other results in the field may affect the approach to Aims 2 and 3.
Canakinumab is a fully human anti-interleukin-1β (anti-IL-1β) monoclonal antibody (IgG-1 class). Canakinumab is designed to bind to human IL-1β and to functionally neutralize the bioactivity of this pro-inflammatory cytokine. The study is a two-arm, multicenter, randomized, double-masked, placebo-controlled clinical trial. 66 subjects will be randomly assigned to receive either monthly subcutaneous injections of 2.0 mg/kg Canakinumab, or placebo for 12 months. All groups will receive standard intensive diabetes treatment with insulin and dietary management. Participants randomly assigned to Canakinumab treatment or placebo will receive a total of 12 injections over one year. All subjects will be followed for 1 year of treatment plus 1- 3 years of additional follow-up until study end. Enrollment is expected to occur over two years.
Fasting hyperglycemia contributes disproportionately to nonenzymatic glycosylation and the microvascular complications of type 2 diabetes. However, little is known about the regulation of glucose concentrations in the fasting state relative to what is known about the postprandial state. The proposed experiment is part of a series of experiments designed to establish how glucagon and insulin interact with their receptors to control fasting glucose in health and in prediabetes.