Dados do Trabalho

Título

The behavior of the animal model of iron deficiency for restless legs syndrome: Is the development period crucial for the model?

Introdução

Experiments with iron-deficient rodents provide us with a valuable model for Restless Legs Syndrome (RLS), and the analysis of motor behavior is essential to assess symptoms, as it implies a manifestation of a desire to move. From 21 (weaning) to 35 days of life is a crucial period for the development of the animal, with high plasticity and easily influenced by environmental factors, such as feeding. Interventions at this moment, which is considered a critical window, can result in positive or negative changes. Therefore, the iron-restricted diet initiated during this period could worsen RLS symptoms.

Objetivo

The aim of the present study is to investigate the behavior of the iron-restricted animal model, with the iron-restricted diet initiated at different times, to refine the experimental model of SPI.

Métodos

The male Wistar rats (n=20) were allocated into a control group (CTRL), iron restriction group starting at 21 days of life (REST21) and iron restriction group starting at 35 days of life (REST35). The animals underwent behavioral assessments by the Open Field Test, Novel Object Recognition Test and Pain Threshold Test at 12 and 18 weeks of age. In addition, the animals' weight, food consumption, hematocrit and glucose were analyzed throughout the experiment.

Resultados

The iron-restricted groups had low hematocrit determinations throughout the experiment and increased fasting glucose at the 12th and 18th week of life (p<0.05), and no difference in pain was found. The animals that received an iron-restricted diet (REST21 and REST35) presented a statistically significant increase in locomotor activity at the 12th week of life compared to the control. However, the REST21 group presented more homogeneous results of symptoms characteristic of RLS. In the recognition memory test, the CTRL animals performed positively for memory, while the REST21 and REST35 animals showed impaired recognition memory in the test at 18 weeks of life.

Conclusões

The results suggest that both iron restriction models demonstrated behavioral changes in locomotion consistent with RLS, however iron restriction at an earlier stage of development may lead to more expressive results of syndrome symptoms. In addition, memory impairment may be consequences of long-term sleep disturbances caused by RLS. The next steps involve analyzing sleep and physiological changes for the complete analysis of both models.

Financial support/acknowledgment: FAPESP 2020/13074-6.

Palavras -chave

Restless legs syndrome, iron-deficient, behavior