View clinical trials related to Insulin Resistance.
Filter by:Muscle strength helps determine a person's quality of life and functional independence. Patients with rheumatoid arthritis often suffer from muscle weakness and a pre-diabetic condition called insulin resistance. By doing this study, the investigators hope to learn why patients with rheumatoid arthritis (RA) suffer from muscle weakness.
The main objective of this study is to investigate the role of female sex hormones in relation to insulin resistance in a controlled human experimental model of menopause and to explore whether exercise and/or hormone treatment (HT) can compensate for loss of endogenous sex hormone production by maintaining insulin sensitivity and metabolic activity at a level equivalent to what is seen in premenopausal women. Loss of ovarian function is associated with an increased incidence of metabolic disease including metabolic syndrome, type 2 diabetes and cardiovascular disease. This increased disease incidence seems to be related to changes in body composition including decreased skeletal muscle mass and increased visceral fat mass as well as decreased whole body fat oxidation and energy expenditure. Regular physical activity decreases general mortality among other things by increasing fat free mass and insulin sensitivity and hereby prevents metabolic syndrome and cardiovascular disease - conditions seen with an increased incidence after menopause and could therefore be a possible treatment. In the present study the Investigators will assess the role of sex hormones in a model of menopause where healthy women are undergoing planned bilateral oophorectomy due to risk of hereditary ovary cancer. The use of this model makes it possible to control the time point for loss of ovarian function and hereby investigate the timeframe and possible contributing factors in a strictly controlled model. 48 premenopausal women will be included in the study. The study is conducted in women who have already been offered surgical oophorectomy. The first 2 months the study will be an observational cohort study. Hereafter the patients will be allocated to one of four groups (n=12) in a randomized controlled trial, addressing the effects of 6 months of exercise with or without HT. Type of surgery has been decided before inclusion based on medical indications. The women will be offered HT according to national guidelines, but the choice is up to them. Randomization applies only to the training intervention. Firstly the Investigators aim at investigating the role of endogenous female sex hormones and HT in relation to insulin resistance, whole body fat oxidation and -energy expenditure, changes in visceral fat mass and fat free mass after oophorectomy. Secondly, the Investigators wish to study the molecular mechanisms behind the oophorectomy-induced insulin resistance with a focus on insulin signaling in skeletal muscle and fat tissue. Lastly, the investigators aim to explore whether exercise and/or HT can compensate for loss of endogenous female sex hormone production by maintaining IS and metabolic activity, hereby preventing future incidents of metabolic disease in relation to menopause. All in all, this project will contribute with new knowledge concerning the question of how endogenous female sex hormones affect insulin sensitivity and metabolic functioning and how exercise may be used as a disease preventive modality for middle-aged women.
Obesity and metabolic disease result when energy intake consistently exceeds energy expenditure. One appealing new target for treatment is the activation of brown adipose tissue (BAT), an organ recently found to be functional in adult humans. Brown adipocytes selectively express uncoupling protein 1 (UCP1), which renders the inner membrane of mitochondria leaky, thereby diverting chemical energy from ATP generation to heat production. Interest in BAT has been spurred by the recognition that in addition to classical BAT depots, other brown-fat-like cells are present in the subcutaneous white adipose tissue (WAT) in animals and also in humans.These cells have structural and functional properties that resemble brown adipocytes, and they are referred to as beige or 'brite' (brown-in-white) adipocytes. Interestingly, browning of WAT can be induced in animals and humans by physiological stimuli such as cold exposure, which increases adrenergic tone, and by exercise, which selectively drives WAT browning through irisin, an exercise-induced myokine. In addition b-adrenergic drugs and other pharmacological agents,such as prostaglandins, can induce browning of white adipose tissue. More recently, one study showed that treatment of C57BL/6 mice with phosphodiesterase inhibitor sildenafil (12 mg/kg/d) for 7 d caused 4.6-fold increase in uncoupling protein-1 expression and promoted establishment of a brown fat cell-like phenotype ("browning") of WAT in vivo. Therefore, the investigators hypothesized that sildenafil can promote browning of white adipose tissue and improves insulin sensitivity in human adults.
In the present study, the investigators will assess the impact of two different feeding patterns (continuous vs intermittent) on insulin sensitivity and muscle mass following bedrest.
In a previous study by Dr. Calkin, the principal investigator of this study, persons with bipolar disorder and either type II diabetes or insulin resistance were found to experience more severe symptoms of bipolar illness and a lower response to treatment, compared to persons with bipolar disorder who did not have type II diabetes or insulin resistance. To further explore these findings, the investigators have developed this study to see if treating insulin resistance (using metformin, a drug used to improve the body's use of insulin) may also help improve the symptoms of bipolar illness.
To asses the modulating properties of the cleaved pentapeptide product of GLP-1 amide.
The purpose of this study is to learn more about what causes insulin resistance. It has been suggested that proper breakdown of fat into energy (oxidation) in the body is important to allow insulin to keep blood sugar in the normal range. The investigators want to know if having one of the fatty acid oxidation disorders could have an influence on insulin action. Fatty acid oxidation disorders are genetic disorders that inhibit one of the enzymes that converts fat into energy. The investigators will study both normal healthy people and people with a long-chain fatty acid oxidation disorder.
Objective: To show that a 1-2 day reduction of caloric intake can reduce the insulin resistance produced by several days of overnutrition. Approach: Healthy volunteers will be admitted to the Clinical Research Center and undergo a baseline euglycemic-hyperinsulinemic clamp study to assess their insulin resistance. Subjects will then start on an overnutrition program for 4 days consisting of 3 meals and 3 snacks containing ~6,000 Kcal/24hours. A second clamp study will be performed on day 5 to demonstrate the overnutrition induced increase in insulin resistance. Starting on day 5 the subject's caloric intake will be reduced to ~1,000 Kcal for 2 days (day 5 and 6). After that on the morning of day 7, a third hyperinsulinemic-euglycemic clamp will be performed to determine whether the reduced caloric intake did reduce insulin resistance and the volunteer will be discharged from the Clinical Research Center.
The adipose (fat) cells under the skin are where individuals store excess fat. The more excess fat they have, the more "strain" they put on these cells which then get bigger and don't work as well as they should. Having some fat under the skin is important. People who have a genetic defect which results in them having almost no fat under their skin have a very high risk of a condition called insulin resistance (where the body does not respond as well to insulin and blood sugar levels rise). This can lead to diabetes and heart disease despite them not being overweight. Scientists have only recently started to understand the importance of fat in insulin resistance and how people unable to store fat very well can have insulin resistance despite not being obese. The investigators have also recently discovered that small changes in a person's genetic code (their body's instruction manual) may also affect their ability to store fat and would like to explore this in more detail. To do this, they will recruit volunteers from the Exeter 10,000 study who gave permission to contact them about further research. The investigators will collect detailed body size measures and blood samples taken before and after a special drink that is high in fat (similar to a thick milk shake), then compare the results between people with and without the particular genetic changes of interest. Knowing more about these genetic changes and how fat cells work could help to improve understanding about why some people develop diabetes and heart disease despite a relatively normal BMI.
This research would take medical interventions in subjects of insulin resistance without abnormal glucose tolerance, to see if there were different prevalence of abnormal glucose tolerance in different groups.