A5033907096- Birth, Development, and Health
- Pancreatic function and diabetes
- Gestational Diabetes Research and Management
- Adipose Tissue and Metabolism
- Growth Hormone and Insulin-like Growth Factors
- Pregnancy and preeclampsia studies
- Diabetes and associated disorders
- Ovarian function and disorders
- Regulation of Appetite and Obesity
- Diabetes Management and Research
- Diabetes Treatment and Management
- Adipokines, Inflammation, and Metabolic Diseases
- Reproductive Biology and Fertility
- Child and Adolescent Health
- Diet and metabolism studies
- Hyperglycemia and glycemic control in critically ill and hospitalized patients
- Epigenetics and DNA Methylation
- Innovations in Medical Education
- Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities
- Adrenal and Paraganglionic Tumors
- Sexual Differentiation and Disorders
- Biochemical Analysis and Sensing Techniques
- Diet, Metabolism, and Disease
- Thyroid Disorders and Treatments
- Ovarian cancer diagnosis and treatment
Columbia University Irving Medical Center
2019-2023
Columbia University
2016-2023
University of Rochester
2023
Albert Einstein College of Medicine
2005-2017
Northwell Health
2013-2016
Cohen Children's Medical Center
2012-2016
Hofstra University
2013-2016
Royal College of Physicians
2016
Children's Hospital at Montefiore
2001-2013
The Bronx Defenders
2013
We directly examined whether visceral fat (VF) modulates hepatic insulin action by randomizing moderately obese (body wt approximately 400 g) Sprague-Dawley rats to either surgical removal of epididymal and perinephric pads (VF-; n = 9) or a sham operation (VF+; 11). Three weeks later, total VF was fourfold increased (8.5 +/- 1.2 vs. 2.1 0.3 g, P < 0.001) in the VF+ compared with VF- group, but whole-body mass (determined using 3H2O) not significantly different. The rates infusion...
Intraabdominal adiposity and insulin resistance are risk factors for diabetes mellitus, dyslipidemia, arteriosclerosis, mortality. Leptin, a fat-derived protein encoded by the ob gene, has been postulated to be sensor of energy storage in adipose tissue capable mediating feedback signal sites involved regulation homeostasis. Here, we provide evidence specific effects leptin on fat distribution vivo action. Leptin (LEP) or vehicle (CON) was administered osmotic minipumps 8 d pair-fed adult...
Long term administration of leptin decreases caloric intake and fat mass improves glucose tolerance. Here we examine whether acutely regulates peripheral hepatic insulin action. Recombinant mouse (0.3 mg/kg·h, Leptin +) or vehicle (Leptin −) were administered for 6 h to 4-month-old rats (n = 20), (3 milliunits/kg·min) clamp studies performed. During physiologic hyperinsulinemia (plasma ∼65 microunits/ml), the rates whole body uptake, glycolysis, glycogen synthesis 2-deoxyglucose uptake in...
Glucagon is a critical regulator of glucose homeostasis; however, mechanisms regulating glucagon action and α-cell function number are incompletely understood. To elucidate the role hepatic receptor (Gcgr) in action, we generated mice with hepatocyte-specific deletion receptor. Gcgr(Hep)(-/-) exhibited reductions fasting blood improvements insulin sensitivity tolerance compared wild-type controls, similar magnitude to changes observed Gcgr(-/-) mice. Despite preservation islet Gcgr...
Intrauterine growth retardation (IUGR) has been linked to the development of type 2 diabetes in adulthood. We developed an IUGR model rats whereby at age 3–6 months animals develop a that is associated with insulin resistance. Hyperinsulinemic-euglycemic clamp studies were performed 8 weeks, before onset obesity and diabetes. Basal hepatic glucose production (HGP) was significantly higher than control (14.6 ± 0.4 vs. 12.3 0.3 mg · kg−1 min−1; P < 0.05). Insulin suppression HGP blunted...
Although glucagon (GLU) plays a pivotal role in glucose homeostasis, its the regulation of fetal growth and maturation is poorly understood. These issues were examined line mice with global deletion GLU receptor (Gcgr−/−), which are characterized by lower blood levels α- δ-cell hyperplasia adults. Ablation Gcgr was deleterious to survival; it delayed β-cell differentiation perturbed proportion β- α-cells embryonic islets. In adults, mutation inhibited progression maturity, affected...
Altered fetal environments, such as a high-fat milieu, induce metabolic abnormalities in offspring. Different postnatal environments reveal the predisposition for adult diseases that occur during period. This study investigates ability of maternal diet (HFD) to program responses HFD reexposure offspring after consuming normal chow 23 weeks weaning. Wild-type CD1 females were fed (H) or control (C) pregnancy and lactation. At 26 age, either reexposed (H-C-H) newly exposed (C-C-H) 19 weeks....
Glucagon secretion dysregulation in diabetes fosters hyperglycemia. Recent studies report that mice lacking glucagon receptor ( Gcgr -/- ) do not develop following streptozotocin (STZ)-mediated ablation of insulin-producing β-cells. Here, we show prevention STZ-treated animals requires remnant insulin action originating from spared residual β-cells: these indeed became hyperglycemic after blockade. Accordingly, developed hyperglycemia induction a more complete, diphtheria toxin (DT)-induced...
The purpose of this study was to determine whether the fasting glucose/insulin ratio is a useful screening test for insulin resistance in prepubertal girls with premature adrenarche. compared sensitivity index calculated from frequently sampled iv glucose tolerance tolbutamide using minimal model computer program. Thirty-three (22 Caribbean Hispanic and 11 African American; mean age, 6.8 yr; bone 8 yr) were studied. All underwent 60-min ACTH stimulation test. also IGF-binding protein-1...
<i>Objective:</i> We report the presentation and 5-year follow-up of 89 African-American (AA) Caribbean-Hispanic (CH) youths with type 2 diabetes mellitus (T2DM) followed at Montefiore Medical Center, Bronx, N.Y., USA, from 1990 to 2000. <i>Methods:</i> The medical records patients T2DM diagnosed between 2000 were reviewed. <i>Results:</i> Over a 10-year period, number pediatric less than 18 years age Center increased tenfold. At presentation, mean was 14...
Recent reports indicate that girls with premature adrenarche are at risk of developing functional ovarian hyperandrogenism and polycystic syndrome (PCOS). As insulin insulin-like growth factors (IGFs) have been implicated in the pathogenesis PCOS, we hypothesize they may also a role adrenarche. Thirty-five prepubertal (23 Caribbean Hispanics 12 Black African-Americans) underwent 60-min ACTH LH-releasing hormone test. Insulin sensitivity (SI) was assessed using frequently sampled iv glucose...
IGF-I is recognized as an insulin sensitizer at the liver and muscle, while recent evidence suggests that IGF-binding protein (IGFBP)-3 acts antagonist. As there a paucity of receptors in IGF-IGFBP system central nervous emerging physiologically relevant, we examined whether effects IGFBP-3 on action are mediated through mechanisms. Intracerebroventricular (ICV) infusion during clamp (3 mU · kg−1 min−1) resulted significant improvement hepatic (50%, P &lt; 0.05). In contrast, ICV...
In addition to its primary role in regulating glucose production from the liver, glucagon has many other actions, reflected by wide tissue distribution of receptor (Gcgr). To investigate regulation insulin secretion and whole body homeostasis vivo, we generated mice overexpressing Gcgr specifically on pancreatic beta-cells (RIP-Gcgr). vivo vitro response was increased 1.7- 3.9-fold RIP-Gcgr compared with controls. Consistent observed increase release glucose, excursion resulting both a...
Intrauterine growth retardation (IUGR) has been linked to the development of Type 2 diabetes in adulthood. We have developed an IUGR model rat whereby animals develop later life. Previous studies demonstrate that administration long-acting glucagon-like-peptide-1 agonist, Exendin-4, during neonatal period prevents rats. exhibit hepatic insulin resistance early life (prior onset hyperglycemia), characterized by blunted suppression glucose production (HGP) response insulin. Basal HGP is also...
Exposure to a high-fat (HF) diet in utero is associated with increased incidence of cardiovascular disease, diabetes, and metabolic syndrome later life. However, the molecular basis this enhanced susceptibility for disease poorly understood. Gene expression microarray genome-wide DNA methylation analyses mouse liver revealed that exposure maternal HF milieu activated genes immune response, inflammation, hepatic dysfunction. analysis 3360 differentially methylated loci, most which (76%) were...
While the incidence of diabetes increases with age, a decrease in beta-cell function independent age-related insulin resistance has not been conclusively determined. We studied secretion (by hyperglycemic clamp) 3-, 9-, and 20-month-old chronically catheterized, awake, Sprague Dawley (SD) rats (n = 78). Insulin action was modulated group old by caloric restriction (CR) or surgical removal visceral fat (VF-). During first 2 h clamp (11 mmol/l glucose), (S(i hyper clamp)) demonstrated...