title: The effects of vitamin C on hypothyroidism-associated learning and memory impairment in juvenile rats.
abstract: In this study the effects of Vitamin C (Vit C) on hypothyroidism-associated learning and memory impairment in juvenile rats was investigated. The pregnant rats were kept in separate cages. After delivery, they were randomly divided into six groups and treated: (1) Control; (2) Propylthiouracil (PTU) which 0.005% PTU in their drinking; (3-5) Propylthiouracil- Vit C groups; besides PTU, dams in these groups received 10, 100 and 500 mg/kg Vit C respectively, (6) one group as a positive control; the intact rats received an effective dose, 100 mg/kg Vit. C. After delivery, the pups were continued to receive the experimental treatments in their drinking water up to 56th day of their life. Ten male offspring of each group were randomly selected and tested in the Morris water maze (MWM) and passive avoidance (PA) which were started at 63th day (one week after stopping of the treatments). Brains were then removed for biochemical measurements. PTU increased time latency and traveled distance during 5 days in MWM while, reduced the spent time in target quadrant in MWM and step-trough latency (STL) in PA. PTU decreased thiol content, superoxide dismutase (SOD) and catalase (CAT) activities in the brain while, increased molondialdehyde (MDA). In MWM test, 10, 100 and 500 mg/kg Vit C reduced time latency and traveled distance without affecting the traveling speed during 5 days. All doses of Vit C increased the spent time in target quadrant in probe trail of MWM and also increased STL in PA test. Vit C increased thiol, SOD and CAT in the brain tissues while, reduced MDA. Results of present study confirmed the beneficial effects of Vit C on learning and memory. It also demonstrated that Vit C has protective effects on hypothyroidism-associated learning and memory impairment in juvenile rats which might be elucidated by the antioxidative effects.
authors.affiliation: Neurocognitive Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Farimah
authors.initials: F
authors.lastname: Beheshti
authors.affiliation: Neurocognitive Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Sareh
authors.initials: S
authors.lastname: Karimi
authors.affiliation: Neurogenic Inflammation Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Farzaneh
authors.initials: F
authors.lastname: Vafaee
authors.affiliation: Neurocognitive Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mohammad Naser
authors.initials: MN
authors.lastname: Shafei
authors.affiliation: Pharmacological Research Center of Medicinal Plants, School of Medicine, Mashhad, University of Medical Sciences, Mashhad, Iran.
authors.forename: Hamid Reza
authors.initials: HR
authors.lastname: Sadeghnia
authors.affiliation: Neurocognitive Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Mosa Al Reza
authors.initials: MAR
authors.lastname: Hadjzadeh
authors.affiliation: Neurogenic Inflammation Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. hosseinim@mums.ac.ir.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Hosseini
mesh_terms: D000367:Age Factors; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology / Q000627:therapeutic use*; D001205:Ascorbic Acid / Q000494:pharmacology / Q000627:therapeutic use*; D001245:Association Learning / Q000187:drug effects* / Q000502:physiology; D005260:Female; D007037:Hypothyroidism / Q000188:drug therapy* / Q000378:metabolism; D008297:Male; D008569:Memory Disorders / Q000188:drug therapy* / Q000378:metabolism; D011247:Pregnancy; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D016896:Treatment Outcome
chemical_list: D000975:Antioxidants; D001205:Ascorbic Acid
keywords: Hypothyroidism; Juvenile; Memory; Neonatal; Oxidative stress; Vitamin C