The effect of electroconvulsive therapy on neuroinflammation, behavior and amyloid plaques in the 5xFAD mouse model of Alzheimer's disease.

Microglial cells are affected in Alzheimer's disease (AD) and interact with amyloid-beta (Aß) plaques. Apart from memory loss, depression is common in patients with AD. Electroconvulsive therapy (ECT) is an anti-depressive treatment that may stimulate microglia, induce neuroinflammation and alter the levels of soluble Aß, but the effects of ECT on microglia and Aß aggregation in AD are not known. We investigated the short- and long-term effects of ECT on neuroinflammation and Aß accumulation. 5xFAD mice received either electroconvulsive stimulation (ECS n = 26) or sham treatment (n = 25) for 3 weeks. Microglia and Aß were analyzed in samples collected 24 h, 5 weeks, or 9 weeks after the last treatment. Aß plaques and microglia were quantified using immunohistochemistry. The concentration of soluble Aß and cytokines was quantified using ELISA and levels of Aß aggregates were measured with Western Blot. Microglial phagocytosis of Aß in the hippocampus was evaluated by flow cytometry in Methoxy-X04 injected mice 24 h following the last ECS treatment. Y-maze and Elevated plus maze were performed to study behavior after 5 weeks. We could not detect any significant short- or long-term effects of ECS on Aß pathology or neuroinflammation, but ECS reduced abnormal behavior in the Elevated Plus maze.

Systematic evaluation of skeletal fractures caused by induction of electroconvulsive seizures in rat state a need for attention and refinement of the procedure.

OBJECTIVE: Electroconvulsive therapy (ECT) is one of the most efficient treatments for major depression. Electroconvulsive seizures (ECS), the animal model of ECT, is widely used to study both mechanisms of action and adverse effects of ECT. As the treatment itself serves as an instant anaesthetic and anaesthetic agents may affect memory functions and behaviour, ECS is traditionally administered without muscle relaxation and anaesthesia. A major problem of unmodified ECS, which has only been addressed peripherally in the literature, is that some animals sustain spinal fractures and subsequent hind leg paralysis (paraplegia). This phenomenon leads to a higher degree of suffering and these animals need to be excluded from the studies. To reach sufficient statistical power, the group sizes are therefore often increased and this may lead to a pre-selected study group in risk of skewing the results. Moreover, the study design of the experiments do not comply with the 3R principles, which advocate for both refinement and reduction of animal experiments. The objective of this study is to systematically evaluate injuries caused by ECS. METHODS: We summarise the incidence of spinal fractures from 24 studies conducted during 2009-2015 in six different rat strains and report preliminary findings on scapular fractures following auricular ECS. RESULTS: In total, 12.8% of all tested animals suffered from spinal fractures and we find an increase in spinal fracture incidence over time. Furthermore, X-ray analyses revealed that some animals displayed scapular fractures. CONCLUSION: We discuss consequences of and possible explanations for ECS-induced fractures. Modifications of the method are highly warranted and we furthermore suggest that all animals are thoroughly examined for discrete fractures.