The purpose of this study is to use a randomized, placebo-controlled study design to rigorously examine the therapeutic potential of intermittent hypoxia (IH) for improving cerebrovascular health in older adults with and without type 2 diabetes mellitus (T2DM).
Gestational Diabetes Mellitus (GDM) currently affects approximately 14% of all pregnancies worldwide. Importantly, the health-related consequences of GDM extend well beyond pregnancy, such that women with a history of GDM have a 40% increased risk of cerebrovascular diseases and a 67% increased risk of dementia, compared to women with a history of uncomplicated pregnancy. Women with a history of GDM have impaired skin microvascular function, compared with women with a history of uncomplicated pregnancy. Therefore, it's likely that GDM results in impaired brain blood vessel function, yet there is little-to-no information regarding the effects of GDM on brain blood vessel health and function after pregnancy.
Therefore, the purpose of the study is to evaluate the effects of GDM on brain blood flow and brain blood vessel function in healthy women with either a history of GDM or uncomplicated pregnancy.
In this study, the investigators will use two different types of ultrasound to non-invasively measure brain blood flow. Brain blood vessel function will be evaluated by examining the brain blood flow responses to increases in carbon dioxide (the increases in carbon dioxide are similar to what is experienced during a breath hold). Additionally, the investigators will compare the brain blood flow results to skin microvascular function to explore potential mechanisms behind possible impairments in brain blood vessel function. Skin microvascular function will be assessed using a minimally invasive technique (intradermal microdialysis for the local delivery of pharmaceutical agents) on dime sized areas of the forearm. Finally, for screening purposes and to further explore potential mechanisms behind any potential impairments in brain blood vessel function, the investigators will perform blood draws to determine the metabolic health of the participants and to analyze for substances that influence blood vessel function.
The goal of this clinical trial is to investigate whether metformin improves vascular function in individuals with prediabetes. The main questions it aims to answer are:
1. Does metformin improve large conduit artery endothelial function in individuals with prediabetes?
2. Does metformin improve microvascular endothelial function in individuals with prediabetes?
Researchers will compare metformin to a placebo to see if metformin improves vascular function in prediabetes.
The trial duration is 12 weeks. Participants will take metformin or a placebo once a day for 2 weeks. After 2 weeks, participants will take metformin or a placebo twice a day for the remaining 10 weeks. There will be a screening visit, two baseline visits, a 4-week safety visit, and two 12-week end-of-study visits. Adherence will be calculated from pill count and adverse events will be quantified via a questionnaire.
Women with a history of gestational diabetes mellitus (GDM) are at a 2-fold greater risk for the development of overt cardiovascular disease (CVD) following the effected pregnancy. While subsequent development of type II diabetes elevates this risk, prior GDM is an independent risk factor for CVD morbidity, particularly, within the first decade postpartum. GDM is associated with impaired endothelial function during pregnancy and decrements in macro- and microvascular function persist postpartum, despite the remission of insulin resistance following delivery. Collectively, while the association between GDM and elevated lifetime CVD risk is clear, and available evidence demonstrates a link between GDM and vascular dysfunction in the decade following pregnancy, the mechanisms mediating this persistent dysfunction remain unexamined.
The purpose of this investigation is to examine the role of endothelin-1, a potent vasoconstrictor, in aberrant microvascular function in otherwise healthy women with a history of GDM and to identify whether this mechanism is influenced by physical activity and sedentary behavior.
The objective of DIAGNODE-3 is to evaluate the efficacy and safety of three intranodal injections of 4 μg of Diamyd also known as retogatein compared to placebo, along with oral Vitamin D supplementation, to preserve endogenous beta cell function and influence glycemic parameters in adolescent and adults recently diagnosed with T1D carrying the HLA DR3-DQ2 haplotype.
This study is being done to find out if metformin is effective at reducing pain by delaying the onset of post-traumatic osteoarthritis (PTOA) after anterior cruciate ligament (ACL) reconstruction. This research study will compare metformin to placebo. The placebo tablet looks exactly like metformin, but contains no metformin. Placebos are used in research studies to see if the results are due to the study drug or due to other reasons.
Metformin is approved by the U.S. Food and Drug Administration (FDA) to treat type II diabetes. Notably, it also has anti-inflammatory effects, suggesting it could benefit people who have an ACL injury and are undergoing ACL reconstruction.
The purpose of this investigation is to examine the mechanisms mediating vascular dysfunction in women who have had gestational diabetes and how metformin may be a valuable treatment tool to improve microvascular function in these women before the onset of disease.