Giuseppe Daniele1, Claudia Lunghi2, Angela Dardano1, Paola Binda3, Giovanni Ceccarini1, Ferruccio Santini1, Laura Giusti1, Annamaria Ciccarone4, Rosario Bellini5, Carlo Moretto5, Maria Concetta Morrone3, Stefano Del Prato6. 1. Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy. 2. Laboratoire des Systèmes Perceptifs, Département d'études Cognitives, École Normale Supérieure, PSL University, CNRS, Paris, France. 3. Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy. 4. Section of Diabetes and Metabolic Diseases, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy. 5. Section Bariatric Surgery, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy. 6. Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy. stefano.delprato@unipi.it.
Abstract
BACKGROUND/ OBJECTIVES: Obesity leads to changes in synaptic plasticity. We aimed at investigating the impact of bariatric surgery (RYGB) on visual neural plasticity (NP) and its relationship with the main gut peptides, leptin, and brain-derived neurotrophic factor (BDNF). SUBJECTS/ METHODS: NP was assessed testing binocular rivalry before and after 2 h of monocular deprivation (index of visual brain plasticity) in 15 subjects with obesity (age 42.3 ± 9.8 years; BMI 46.1 ± 4.9 kg/m2) before and after RYGB. Gut peptides, leptin, and BDNF were obtained at baseline and 6 months after surgery in 13 subjects. RESULTS: A significant reduction in BMI (p < 0.001 vs. baseline) and a significant increase of disposition index (DI, p = 0.02 vs baseline) were observed after RYGB. Total and active GLP-1 release in response to glucose ingestion significantly increased after RYGB, while no changes occurred in VIP, GIP, and BDNF levels. Fasting leptin concentration was lower after RYGB (p = 0.001 vs. baseline). Following RYGB, NP was progressively restored (p < 0.002). NP was correlated with DI and fasting glucose at baseline (r = 0.75, p = 0.01; r = -0.7, p = 0.02; respectively), but not with BMI. A positive correlation between post-pre-RYGB changes in AUCactive GLP-1 and NP was observed (r = 0.70, p < 0.01). Leptin was inversely correlated with NP 6 months after surgery (r = -0.63, p = 0.02). No correlation was observed between GIP, VIP, BDNF, and NP. CONCLUSIONS: Visual plasticity is altered in subjects with obesity, and it can be restored after RYGB. The improvement may be mediated by amelioration of insulin sensitivity, increased GLP-1 levels, and reduced leptin levels.
BACKGROUND/ OBJECTIVES: Obesity leads to changes in synaptic plasticity. We aimed at investigating the impact of bariatric surgery (RYGB) on visual neural plasticity (NP) and its relationship with the main gut peptides, leptin, and brain-derived neurotrophic factor (BDNF). SUBJECTS/ METHODS: NP was assessed testing binocular rivalry before and after 2 h of monocular deprivation (index of visual brain plasticity) in 15 subjects with obesity (age 42.3 ± 9.8 years; BMI 46.1 ± 4.9 kg/m2) before and after RYGB. Gut peptides, leptin, and BDNF were obtained at baseline and 6 months after surgery in 13 subjects. RESULTS: A significant reduction in BMI (p < 0.001 vs. baseline) and a significant increase of disposition index (DI, p = 0.02 vs baseline) were observed after RYGB. Total and active GLP-1 release in response to glucose ingestion significantly increased after RYGB, while no changes occurred in VIP, GIP, and BDNF levels. Fasting leptin concentration was lower after RYGB (p = 0.001 vs. baseline). Following RYGB, NP was progressively restored (p < 0.002). NP was correlated with DI and fasting glucose at baseline (r = 0.75, p = 0.01; r = -0.7, p = 0.02; respectively), but not with BMI. A positive correlation between post-pre-RYGB changes in AUCactive GLP-1 and NP was observed (r = 0.70, p < 0.01). Leptin was inversely correlated with NP 6 months after surgery (r = -0.63, p = 0.02). No correlation was observed between GIP, VIP, BDNF, and NP. CONCLUSIONS: Visual plasticity is altered in subjects with obesity, and it can be restored after RYGB. The improvement may be mediated by amelioration of insulin sensitivity, increased GLP-1 levels, and reduced leptin levels.