Estudo do comportamento depressivo associado ao modelo de lesão por pressão

Abstract

Evaluation of depressive-like behavior associated with a model of pressure injury

Pressure injury (PI) is a localized injury to the underlying skin and/or soft tissues, usually on a prominent bone or related to the use of a medical device or other artifacts and is a major concern in the health services due to its high incidence. These types of injuries are considered as factors that cause suffering. Some studies have suggested their association with the development of depression. Depression is a severe and disabling psychiatric disorder, considered by the World Health Organization as the main cause of disability worldwide. Thus, it is necessary to identify the factors involved in its emergence. In this regard, we aimed to investigate the effects of the animal model of pressure injury on depressive-like behaviors and oxidative parameters on the brain areas of mice. Male Swiss mice (25-30g) were used, which for 4 consecutive days were submitted to the ischemia/reperfusion cycle (I/R), for 24 hours. They had two imams placed on the skin of the dorsal region. On the 5th day the animals were submitted to the following behavioral tests: open field test, elevated plus maze, tail suspension, and sucrose preference. Afterward, the animals were euthanized by decapitation and the prefrontal cortex, hippocampus and striatum were dissected to measure the oxidative parameters. In the open field test, the PI group showed a reduction in the number of crossings compared to the control group, while the number of rearings and groomings did not change. In the elevated plus maze test, the PI group presented a decrease in the number of entries and time spent in the open arm when compared to the control group, in addition, the number of entries and time spent in the closed arm were higher in the PI group when compared to the control group. In the tail suspension test, the PI group showed an increase in immobility time when compared to the control group. In the preference test for sucrose, PI induced an anhedonia-like behavior shown by a reduction of sucrose consumption. Regarding the analysis of the oxidative parameters, the PI caused an increase in the levels of malondialdehyde in all the brain areas studied and a reduction in the levels of glutathione. Taken together, our results showed that PI caused impairment of the locomotor and exploratory activity, induced anxiety-like, depressive-like behavior and altered the oxidative parameters in the brain areas of the animals, suggesting the need for the development of other studies investigating the mechanisms involved in this context and demonstrating the importance of an increased attention to mood disorders in patients with pressure injury.