Carotid Body Resection Prevents Short-Term Spatial Memory Decline in Prediabetic Rats Without Changing Insulin Signaling in the Hippocampus and Prefrontal Cortex

Adv Exp Med Biol. 2023:1427:143-152. doi: 10.1007/978-3-031-32371-3_16.

Abstract

Individuals who develop type 2 diabetes (T2D) at an early age are at higher risk of developing neurodegenerative disorders such as Alzheimer's and Parkinson's disease. A shared dysfunctional characteristic between T2D and these neurodegenerative disorders is insulin resistance. Recently, it was shown that prediabetes animals and patients exhibited increased carotid body (CB) activity. Moreover, these organs are deeply involved in the development of metabolic diseases, since upon abolishment of their activity via carotid sinus nerve (CSN) resection, several dysmetabolic features of T2D were reverted. Herein, we investigated if CSN resection may also prevent cognitive impairment associated with brain insulin resistance. We explored a diet-induced prediabetes animal model where Wistar rats are kept in a high fat-high sucrose (HFHSu) diet for 20 weeks. We evaluated CSN resection effects on behavioral parameters and on insulin signaling-related proteins levels, in the prefrontal cortex and the hippocampus. HFHSu animals exhibited impaired short-term memory evaluated by the y-maze test. Remarkably, CSN resection prevented the development of this phenotype. HFHSu diet or CSN resection did not promote significant alterations in insulin signaling-associated proteins levels. Our findings suggest that CBs modulation might have a role in preventing short-term spatial memory deficits associated with peripheral dysmetabolic states.

Keywords: Carotid body; Insulin resistance; Metabolic diseases; Neurodegenerative disorders.

MeSH terms

  • Animals
  • Carotid Body* / physiology
  • Diabetes Mellitus, Type 2* / complications
  • Diabetes Mellitus, Type 2* / metabolism
  • Diabetes Mellitus, Type 2* / surgery
  • Diet, High-Fat / adverse effects
  • Hippocampus / metabolism
  • Insulin / metabolism
  • Insulin Resistance* / physiology
  • Memory Disorders / etiology
  • Memory Disorders / prevention & control
  • Memory, Short-Term
  • Prediabetic State* / metabolism
  • Prediabetic State* / surgery
  • Prefrontal Cortex / metabolism
  • Rats
  • Rats, Wistar

Substances

  • Insulin