Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) caused by demyelination, immune cell infiltration, and axonal damage. Herein, we sought to investigate the influence of physical exercise on mice experimental autoimmune encephalomyelitis (EAE), a reported MS model. Data show that both strength and endurance training protocols consistently prevented clinical signs of EAE and decreased oxidative stress, an effect which was likely due to improving genomic antioxidant defense-nuclear factor erythroid 2-related factor (Nrf2)/antioxidant response elements (ARE) pathway-in the CNS. In addition, physical exercise inhibited the production of pro-inflammatory cytokines interferon (IFN)-γ, interleukin (IL)-17, and IL-1β in the spinal cord of mice with EAE. Of note, spleen cells obtained from strength training group incubated with MOG35-55 showed a significant upregulation of CD25 and IL-10 levels, with a decrease of IL-6, MCP-1, and tumor necrosis factor (TNF)-α production, mainly, during acute and chronic phase of EAE. Moreover, these immunomodulatory effects of exercise were associated with reduced expression of adhesion molecules, especially of platelet and endothelial cell adhesion molecule 1 (PECAM-1). Finally, physical exercise also restored the expression of tight junctions in spinal cord. Together, these results demonstrate that mild/moderate physical exercise, when performed regularly in mice, consistently attenuates the progression and pathological hallmarks of EAE, thereby representing an important non-pharmacological intervention for the improvement of immune-mediated diseases such as MS. Graphical Abstract Schematic diagram illustrating the beneficial effects of physical exercise during experimental model of MS. Physical exercise, especially strength (ST) and endurance (ET) training protocols, inhibits the development and progression of disease, measured by the mean maximal clinical score (1.5 and 1.0, respectively), with inhibition of 30 % and 50 %, respectively, based on the AUC, compared with EAEuntreated group. In addition, ST and ET decreased oxidative stress, possibly, through genomic antioxidant defense, Nrf2-Keap1 signaling pathway, in the CNS. Physical exercise inhibited the production of inflammatory cytokines, such as IFN-γ, IL-17 and IL-1β in the spinal cord after EAE induction, as well as spleen cells obtained from ST group showed a significant upregulation of regulatory T cell markers, such as CD25 and IL-10 levels, and blocked IL-6, MCP-1 and TNF-α production, mainly, during acute and chronic phase of EAE. Finally, these immunomodulatory effects of exercise were associated with inhibition of adhesion molecules and reestablishment of tight junctions expression in spinal cord tissue, thereby limiting BBB permeability and transmigration of autoreactive T cells to the CNS. NO, nitric oxide; GPx, glutathione peroxidase, GSH, glutathione; Nrf2, nuclear factor (erythroid-derived 2)-like 2; CNS, central nervous system; BBB, blood-brain barrier; IFN-g, interferon-gamma; IL-17, interleukin 17; IL-1b, interleukin-1beta.
However on a lighter note, the UK Home office and the European Union now enshrines the 3Rs (Reduction refinement, replacement) of animal use as part of use of animals in research.
Tietz SM, Zwahlen M, Jahromi NH, Baden P, Lazarevic I, Enzmann G, Engelhardt B. Eur J Immunol. 2016. doi: 10.1002/eji.201546272. [Epub ahead of print]
Experimental autoimmune encephalomyelitis (EAE) in rodents is frequently used as an animal model for multiple sclerosis (MS). A potential role of individual genes in MS pathogenesis is regularly investigated by comparing EAE development in gene-targeted mice with that in their wild-type littermates. Clinical disease in EAE models ultimately amounts to motor dysfunction, thus EAE severity is generally scored in correlation to the severity of paralysis. However, there is no international standard scoring system, which research groups would use to measure EAE severity and clinical assessment scales mostly in use reach from 0-3 points to 0-6 points
EAE is one of the problem areas because it is considered “severe” because of what happens to the beasties.
So in this study they look at the common or garden EAE scoring system and ask if they attempt to 3Rs-it and put more elements into this does it improve this?
Our vet asked do the beasties get headaches when they get EAE?…my response was they had never told me that they do).
The scoring used were
In the 5.5 you add a few extra bits like a grid walk a righting test and a hanging test to check front legs and scoring one side or the other. Was if more refined to detect more info…..well the long and the short was no it didn’t and only took more time to do and in the end of the day didn’t really make much of a difference so the 3Rs attempt was pain in the Rs and because more handling was involved their was probably more stress to the animals
But it is not always so frivolous, spending our nights checking the beasties at the behest of the Whim of Home Office or Vet is no fun.
When scoring we use something similar. Many people use 0= normal 1 = limp tail, 2= paresis of hindlimb 3= paralysis of hindlimbs
For this our scoring system has 8 sections 0= normal, 1 = limp tail, 2= impaired righting reflex, 3= hindlimb paresis and 4 = hindlimb paralysis but half steps e.g. 0.5 = partially limp tail, 3.5 = not quite paralysed one limb paralysed. If an animal is moribund it would be removed, which is difficult because SJL tend to lay on their side immobile compared to C57BL/6 mice..However we don’t use SJL mice
Anyway we have an expanded scoring system because it gives more capacity to detect differences between the groups possibly meaning that smaller group sizes could be used = 3Rs
0 = normal 1 = limp tail 2= paralysis of leg
0= mormal 0.5 = paresis of tail, 1= limp tail, 1.5 = paresis of limb
2 = paralysis
0, 1, 1, 1, 1, 1, 2 verses 1, 1, 1, 1, 1, 1, 2 p=0.710 no difference
0, 0.5, 0.5, 0.5, 0.5, 1, 1.5 verses 1, 1, 1, 1, 1, 1, 2 p=0.017 =difference
Based on Mann Whitney U test using Sigma plot
However, you can make it very complicated and have say a 16 point score. There was once a study used to justify a clinical trial when there was clinical score or a difference of 2.5 verses 3.5 P<0.05 but when you realised the scoring system was 0-16 and this meant the drug changed a partially limb tail to almost a partially limp tail and the group sizes had over 100 animals in them, you say “Where is the 3 Rs in that?” and the effect is so marginal to be non- existent…trial failed.
Therefore the “smack you in the eye test” is an useful part of data analysis.
We have added outcomes to the standard scoring tests that give additional information and yes this is 3Rs
However what is interesting is the comments of the referees are on show for this journal and they complained that the scores were around 1 for the score 0-3 score and about 2-3 in the 5.5 saying the disease was mild and so perhaps lacking a quality control element if more severe disease is the norm. The best bit however was the letter from the Editorial Board (cpoied form = copied from:-) their online pdf). It is nice to see that their Engrish is up to scratch.
Wonder if it was written on a phone? (P.S. Yes I missed some corkers)
Have a fun Olympic/Paralympic Games in Rio 2016
Not Interested in Animal Stuff. No problem Don’t read!
Did you know that the UK Government want us to talk about animal work