Radiologic evidence that hypothalamic gliosis is improved after bariatric surgery in obese women with type 2 diabetes

Abstract

Background/Objectives-Hypothalamic neurons play a major role in the control of body mass. Obese subjects present radiologic signs of gliosis in the hypothalamus, which may reflect the damage or loss of neurons involved in whole-body energy homeostasis. It is currently unknown if hypothalamic gliosis (1) differs between obese nondiabetic (ND) and obese diabetic subjects (T2D) or (2) is modified by extensive body mass reduction via Roux-n-Y gastric bypass (RYGB). Subjects/Methods-Fifty-five subjects (all female) including lean controls (CT; n = 13), ND (n = 28), and T2D (n = 14) completed at least one study visit. Subjects underwent anthropometrics and a multi-echo MRI sequence to measure mean bilateral T2 relaxation time in the mediobasal hypothalamus (MBH) and two reference regions (amygdala and putamen). The obese groups underwent RYGB and were re-evaluated 9 months later. Analyses were by linear mixed models. Results-Analyses of T2 relaxation time at baseline showed a group by region interaction only in the MBH (P < 0.0001). T2D had longer T2 relaxation times compared to either CT or ND groups. To examine the effects of RYGB on hypothalamic gliosis a three-way (group by region by time) mixed effects model adjusted for age was executed. Group by region (P < 0.0001) and region Licio A. Velloso,

Investigating obesity‐associated brain inflammation using quantitative water content mapping

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Animal Models of Metabolic Disorders in the Study of Neurodegenerative Diseases: An Overview

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Strategies to Understand the Weight‐Reduced State: Genetics and Brain Imaging

“…Using quantitative structural neuroimaging techniques, several studies have found radiologic evidence of gliosis of the MBH in association with obesity in adults (103,113,114) and children (115). Moreover, longer MBH T2 relaxation times correlate with greater visceral adiposity (115,116) and insulin resistance independent of obesity (113) and were observed in women with obesity with type 2 diabetes mellitus relative to women with obesity who were nondiabetic (102).…”