Inflammation in the hippocampus (the brain’s memory center) significantly alters motivation and behavior in mice, including foraging behavior, with notable differences between males and females, a recent study reveals.
The hippocampus plays a crucial role in memory formation, learning, and emotional regulation. Neuroinflammation of the hippocampus occurs in a variety of diseases and disorders such as Alzheimer’s, multiple sclerosis, and depression.
People with these diseases often experience common symptoms such as apathy, difficulty with daily activities, and changes in food preferences. These symptoms also tend to be more severe in women than in men.
“While inflammation in the hippocampus is not solely responsible for behavioral changes, it likely triggers broader brain activity that influences behavior,” said study co-author Dr. Laura Bradfield, director of the Brain Laboratory. and Behavior at the University of Technology Sydney (UTS). .
“This research suggests that treatments targeting hippocampal neuroinflammation could help reduce cognitive and behavioral symptoms in these diseases and improve brain health, especially in women,” he said.
The study, “Lipopolysaccharide-induced hippocampal neuroinflammation causes sex-specific alterations in action selection, food approach memories, and neuronal activation,” was published in the journal Brain behavior and immunity.
The researchers induced inflammation by exposing cultures of mouse hippocampal cells in the laboratory to lipopolysaccharide, a bacterial toxin that provokes a strong immune response.
They found that the toxin only activated neurons in the presence of other types of brain cells, such as microglia and astrocytes. This highlights the complex interaction between different cell types during inflammation.
To examine behavior, the researchers injected lipopolysaccharide directly into the hippocampus of mice and observed their activity and foraging behaviors.
They found that neuroinflammation increased levels of movement and activity in both sexes, but had a more pronounced effect on foraging behaviors in women.
Lead author Dr Kiruthika Ganesan, who recently completed her PhD at UTS, said the study underlines the importance of considering sex-specific effects when developing treatments for neurological diseases.
“These findings provide new insights into how neuroinflammation affects brain function, which could pave the way for new therapies that address the behavioral and cognitive symptoms of a variety of diseases,” he said.
“We hope that future research will focus on understanding the mechanisms behind these sex-specific effects, including the influence of hormones such as estrogen and their implications for brain health.”