High interindividual variability in dose-dependent reduction in speed of movement after exposing C. elegans to shock waves

Abstract

In blast-related mild traumatic brain injury (br-mTBI) little is known about the connections between initial trauma and expression of individual clinical symptoms. Partly due to limitations of current in vitro and in vivo models of br-mTBI, reliable prediction of individual short- and long-term symptoms based on known blast input has not yet been possible. Here we demonstrate a dose-dependent effect of shock wave exposure on C. elegans using shock waves that share physical characteristics with those hypothesized to induce br-mTBI in humans. Increased exposure to shock waves resulted in decreased mean speed of movement while increasing the proportion of worms rendered paralyzed. Recovery of these two behavioral symptoms was observed during increasing post-traumatic waiting periods. Although effects were observed on a population-wide basis, large interindividual variability was present between organisms exposed to the same highly controlled conditions. Reduction of cavitation by exposing worms to shock waves in polyvinyl alcohol resulted in reduced effect, implicating primary blast effects as damaging components in shock wave induced trauma. Growing worms on NGM agar plates led to the same general results in initial shock wave effect in a standard medium, namely dose-dependence and high interindividual variability, as raising worms in liquid cultures. Taken together, these data indicate that reliable prediction of individual clinical symptoms based on known blast input as well as drawing conclusions on blast input from individual clinical symptoms is not feasible in br-mTBI.

Is Radial Extracorporeal Shock Wave Therapy Combined with a Specific Rehabilitation Program (rESWT + RP) More Effective than Sham-rESWT + RP for Acute Hamstring Muscle Complex Injury Type 3b in Athletes? Study Protocol for a Prospective, Randomized, Double-Blind, Sham-Controlled Single Centre Trial

“…In this regard it should be kept in mind that the majority of clinical trials on rESWT that are listed in the PEDro database [37,38] were performed with the Swiss DolorClast [34]. Furthermore, except of the Power+ handpiece of the Swiss DolorClast, the Evo Blue handpiece was the most powerful handpiece in a comparative study measuring cavitation generated with rESWs [53] (the relevance of cavitation in mediating molecular and cellular mechanisms of ESWT on the musculoskeletal system was discussed in [43,[53][54][55]).…”

Inter-individual variability in the foraging behaviour of traplining bumblebees

“…Inter-individual behavioural variability has been described in a wide range of taxa, from invertebrates (nematodes 4 , cnidarians 5 , molluscs 6 , insects 7, 8 ) to mammals 9 , including humans 10 . The existence of such individualistic behavioural traits may have different adaptive values depending on the ecology of the species 11–13 .…”

Functionality and Robustness of Injured Connectomic Dynamics in C. elegans: Linking Behavioral Deficits to Neural Circuit Damage

“…Recent experimental work which induced mild TBI in C. elegans found that increasing the number of shock waves to which the worm was exposed reduced the worm’s average speed and, in many cases, led to temporary paralysis [45]. The results of our simulations can be compared to these results:…”

“…Recent blast injury studies on C. elegans show that many of the nematodes display temporary paralysis before recovering to crawling behaviors [45]. We would suggest that during the peak of the FAS, the injury levels on many of the nematodes are above μ *, thus leading to a collapse of a limit cycle to a fixed point where no motion is possible, i.e.…”

“…Further computational work could also find neuronal proxies for additional behavioral modes so as to enable a more complete mapping. Recent work on blast injuries of worms [45] could potentially help extend the analysis by providing injured eigenworm mode projections.…”