Growth hormone receptor antagonism with pegvisomant in insulin resistant non-diabetic men: A phase II pilot study.

Growth hormone (GH) is known to affect insulin and glucose metabolism.  Blocking its effects in acromegalic patients improves diabetes and glucose metabolism. We aimed to determine the effect of pegvisomant, a GH receptor antagonist, on insulin resistance, endogenous glucose production (EGP) and lipolysis in insulin resistant non-diabetic men.

Subchronic sleep restriction causes tissue-specific insulin resistance.

Context: Short sleep duration is associated with an increased risk of type 2 diabetes. Subchronic sleep restriction (SR) causes insulin resistance, but the mechanisms and roles of specific tissues are unclear.

Objective: The purpose of this article was to determine whether subchronic SR altered (1) hepatic insulin sensitivity, (2) peripheral insulin sensitivity, and (3) substrate utilization.

Changes in post-prandial glucose and pancreatic hormones, and steady-state insulin and free fatty acids after gastric bypass surgery.

Background: Changes in the multiple mechanisms that regulate glucose metabolism after gastric bypass (RYGB) are still being unveiled. The objective of this study was to compare the changes of glucose and pancreatic hormones [C-peptide, glucagon, and pancreatic polypeptide (PP)] during a meal tolerance test (MTT) and steady-state insulin and free fatty acid (FFA) concentrations during euglycemic-hyperinsulinemic clamp 14 days and 6 months after RYGB in morbidly obese nondiabetic patients.

Methods: Two groups were studied at baseline and at 14 days: the RYGB followed by caloric restriction group (RYGB, n = 12) and the equivalent caloric restriction alone group (Diet, n = 10), to control for energy intake and weight loss.

Cutis Verticis Gyrata in Men Affected by HIV-Related Lipodystrophy.

We report the occurrence of cutis verticis gyrata (CVG), a disfiguring dermatological condition, in four patients with HIV-related lipodystrophy (HIVLD). These four patients had abnormal metabolic and hormonal lab values which we compare with metabolic and hormonal perturbations cited in previous HIVLD cohorts. In addition, we describe the sole use of poly-L-lactic acid as a potential treatment for decreasing the appearance of CVG-associated ridges.

Severe hypercalcemic hyperparathyroidism developing in a patient with hyperaldosteronism and renal resistance to parathyroid hormone.

We evaluated an African American woman referred in 1986 at age 33 years because of renal potassium and calcium wasting and chronic hip pain. She presented normotensive, hypokalemic, hypocalcemic, normophosphatemic, and hypercalciuric. Marked hyperparathyroidism was evident.

Assessing the Association between Leptin and Bone Mineral Density in HIV-Infected Men.

HIV-infected individuals are at risk for decreased bone mineral density (BMD). The known risk factors for bone loss do not fully explain the increased risk in this population. There is emerging evidence that leptin, a hormone secreted by adipocytes, plays an important role in bone metabolism.

Sarcopenia with limited mobility: an international consensus.

A consensus conference convened by the Society of Sarcopenia, Cachexia and Wasting Disorders has concluded that "Sarcopenia, ie, reduced muscle mass, with limited mobility" should be considered an important clinical entity and that most older persons should be screened for this condition. "Sarcopenia with limited mobility" is defined as a person with muscle loss whose walking speed is equal to or less than 1 m/s or who walks less than 400 m during a 6-minute walk, and who has a lean appendicular mass corrected for height squared of 2 standard deviations or more below the mean of healthy persons between 20 and 30 years of age of the same ethnic group. The limitation in mobility should not clearly be a result of otherwise defined specific diseases of muscle, peripheral vascular disease with intermittent claudication, central and peripheral nervous system disorders, or cachexia.

Insulin resistance in non-obese subjects is associated with activation of the JNK pathway and impaired insulin signaling in skeletal muscle.

Background: The pathogenesis of insulin resistance in the absence of obesity is unknown. In obesity, multiple stress kinases have been identified that impair the insulin signaling pathway via serine phosphorylation of key second messenger proteins. These stress kinases are activated through various mechanisms related to lipid oversupply locally in insulin target tissues and in various adipose depots.

Enhanced uridine bioavailability following administration of a triacetyluridine-rich nutritional supplement.

Background: Uridine is a therapy for hereditary orotic aciduria and is being investigated in other disorders caused by mitochondrial dysfunction, including toxicities resulting from treatment with nucleoside reverse transcriptase inhibitors in HIV. Historically, the use of uridine as a therapeutic agent has been limited by poor bioavailability. A food supplement containing nucleosides, NucleomaxX®, has been reported to raise plasma uridine to supraphysiologic levels.

Effects of insulin-like growth factor (IGF)-I/IGF-binding protein-3 treatment on glucose metabolism and fat distribution in human immunodeficiency virus-infected patients with abdominal obesity and insulin resistance.

Context: HIV-infected patients on antiretroviral therapy are at increased risk for excess visceral adiposity and insulin resistance. Treatment with GH decreases visceral adiposity but worsens glucose metabolism. IGF-I, which mediates many of the effects of GH, improves insulin sensitivity in HIV-negative individuals.

Boosting dose ritonavir does not alter peripheral insulin sensitivity in healthy HIV-seronegative volunteers.

Background: Some HIV protease inhibitors (PIs), including full-dose ritonavir (800 mg) and ritonavir-boosted lopinavir, acutely induce insulin resistance in the absence of HIV infection and changes in body composition. Boosting dose ritonavir (100-200 mg) is the most commonly prescribed PI, yet its effects on glucose metabolism have not been described in the absence of another PI.

Methods: In this randomized, double-blind, cross-over study, a single dose of ritonavir 200 mg or placebo was given to healthy HIV-seronegative volunteers before assessment of insulin sensitivity by euglycemic hyperinsulinemic clamp.

A genome-wide association study of carotid atherosclerosis in HIV-infected men.

Background: The role of host genetics in the development of subclinical atherosclerosis in the context of HIV-infected persons who are being treated with highly active antiretroviral therapy (HAART) is not well understood.

Methods: The present genome-wide association study (GWAS) is based on 177 HIV-positive Caucasian males receiving HAART who participated in the Fat Redistribution and Metabolic Change in HIV Infection (FRAM) Study. Common and internal carotid intima-media thicknesses (cIMT) measured by B-mode ultrasound were used as a subclinical measure of atherosclerosis.

The protease inhibitor combination lopinavir/ritonavir does not decrease insulin secretion in healthy, HIV-seronegative volunteers.

Background: HIV protease inhibitors have been shown to worsen glucose and lipid metabolism. Recent studies have suggested that protease inhibitors can impair insulin secretion in HIV-infected patients. We studied the effects of the protease inhibitor combination lopinavir and ritonavir on insulin secretion, insulin sensitivity, and lipid metabolism in HIV-negative persons.

Improvement in peripheral glucose uptake after gastric bypass surgery is observed only after substantial weight loss has occurred and correlates with the magnitude of weight lost.

Introduction: Altered gut and pancreatic hormone secretion may bolster resolution of insulin resistance after Roux-en-Y gastric bypass (RYGB), but the independent effects of weight loss and hormonal secretion on peripheral glucose disposal are unknown.

Methods: Two groups of nondiabetic morbidly obese patients were studied: RYGB followed by standardized caloric restriction (RYGB, n = 12) or caloric restriction alone (diet, n = 10). Metabolic evaluations (euglycemic-hyperinsulinemic clamp, meal tolerance test) were done at baseline and 14 days (both groups) and 6 months after RYGB.

Can the use of creatine supplementation attenuate muscle loss in cachexia and wasting?

Purpose Of Review: Weight loss and low BMI due to an underlying illness have been associated with increased mortality, reduced functional capacity, and diminished quality of life. There is a need for well tolerated, long-term approaches to maintain body weight in patients with cachexia or wasting. The purpose of this review is to highlight the scientific and clinical evidence derived from the recent literature investigating the rationale for and potential medical use of creatine supplementation in patients with cachexia or wasting.

The acute effects of HIV protease inhibitors on insulin suppression of glucose production in healthy HIV-negative men.

Background: The effects of different HIV protease inhibitors (PIs) on peripheral insulin resistance have been described, but less is known about their effects on insulin suppression of endogenous glucose production (EGP).

Methods: We tested the acute effects of 3 PIs, indinavir, ritonavir, and amprenavir, on EGP quantified by stable isotope techniques during the hyperinsulinemic, euglycemic clamp in 3 similar placebo-controlled protocols.

Results: EGP was higher with indinavir in the hyperinsulinemic state than with placebo (4.

Creatine fails to augment the benefits from resistance training in patients with HIV infection: a randomized, double-blind, placebo-controlled study.

Background: Progressive resistance exercise training (PRT) improves physical functioning in patients with HIV infection. Creatine supplementation can augment the benefits derived from training in athletes and improve muscle function in patients with muscle wasting. The objective of this study was to determine whether creatine supplementation augments the effects of PRT on muscle strength, energetics, and body composition in HIV-infected patients.

The effects of recombinant human leptin on visceral fat, dyslipidemia, and insulin resistance in patients with human immunodeficiency virus-associated lipoatrophy and hypoleptinemia.

Context: Leptin deficiency is associated with dyslipidemia and insulin resistance in animals and humans with lipoatrophy; leptin replacement ameliorates these abnormalities.

Objective: The objective of the study was to evaluate the effects of leptin therapy in lipoatrophic HIV-infected patients with dyslipidemia and hypoleptinemia.

Design: This was a 6-month, open-label, proof-of-principle pilot study.

Effects of ritonavir and amprenavir on insulin sensitivity in healthy volunteers.

Background: Some HIV protease inhibitors (PIs) have been shown to induce insulin resistance in vitro but the degree to which specific PIs affect insulin sensitivity in humans is less well understood.

Methods: In two separate double-blind, randomized, cross-over studies, we assessed the effects of a single dose of ritonavir (800 mg) and amprenavir (1200 mg) on insulin sensitivity (euglycemic hyperglycemic clamp) in healthy normal volunteers.

Results: Ritonavir decreased insulin sensitivity (-15%; P = 0.

Technical evaluation of in vivo abdominal fat and IMCL quantification using MRI and MRSI at 3 T.

Objectives: The objectives of this study were to develop protocols that measure abdominal fat and calf muscle lipids with magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS), respectively, at 3 T and to examine the correlation between these parameters and insulin sensitivity.

Materials And Methods: Ten nondiabetic subjects [five insulin-sensitive (IS) subjects and five insulin-resistant (IR) subjects] were scanned at 3 T. Visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were segmented semiautomatically from abdominal imaging.

Testosterone supplementation of megestrol therapy does not enhance lean tissue accrual in men with human immunodeficiency virus-associated weight loss: a randomized, double-blind, placebo-controlled, multicenter trial.

Context: Reduced energy intake is a primary factor in HIV-associated wasting. Megestrol acetate (MA) stimulates appetite and weight gain. However, much of the weight gained is fat, possibly as a result of MA-induced hypogonadism.