Lavrov, I. | bioRxiv Science

bioRxiv2019

Mesenchymal stem cells therapy for spinal cord contusion: a comparative study on small and large animal models

Here, we provided a first comparative study of the therapeutic potential of allogeneic mesenchymal stem cells derived from bone marrow (BM-MSCs), adipose tissue (AD-MSCs), and dental pulp (DP-MSCs) embedded in fibrin matrix in a small (rat) and large (pig) spinal cord injury (SCI) model during sub-acute period of spinal contusion. Results of behavioral, electrophysiological, histological assessment, as well as results of immunohistochemistry and RT-PCR analysis suggest that application of AD-MSCs combined with a fibrin matrix in a subacute period in rats (2 weeks after injury) provides significantly higher post-traumatic regeneration compared to a similar application of BM-MSCs or DP-MSCs. Within the rat model, use of AD-MSCs resulted in a marked change in (1) restoration of locomotor activity and conduction along spinal axons, (2) reduction of post-traumatic cavitation and enhancing tissue retention, and (3) modulation of microglial and astroglial activation. The effect of therapy with an autologous application of AD-MSCs was also confirmed in subacute period after spinal contusion in pigs (6 weeks after injury), however, with only partial replication of the findings observed in rats, i.e. (1) partial restoration of the somatosensory spinal pathways, (2) reduction of post-traumatic cavitation and enhancing tissue retention, and (3) modulation of astroglial activation in dorsal root entry zone. The results of this study suggest that application of AD-MSCs embedded in fibrin matrix at the site of SCI during the subacute period can facilitate regeneration of nervous tissue in rats and pigs. These results, for the first time, provide robust support for the use of AD-MSC to treat subacute SCI.

cell biology↗

bioRxiv2019

Multifactorial motor behavior assessment for real-time evaluation of emerging therapeutics to treat neurologic impairments

Integrating multiple assessment parameters of motor behavior is critical for understanding neural activity dynamics during motor control in both intact and dysfunctional nervous systems. Here, we described a novel approach (termed Multifactorial Behavioral Assessment (MfBA)) to integrate, in real-time, electrophysiological and biomechanical properties of rodent spinal sensorimotor network activity with behavioral aspects of motor task performance. Specifically, the MfBA simultaneously records limb kinematics, multi-directional forces and electrophysiological metrics, such as high-fidelity chronic intramuscular electromyography synchronized in time to spinal stimulation in order to characterize spinal cord functional motor evoked potentials (fMEPs). Additionally, we designed the MfBA to incorporate a body weight support system to allow bipedal and quadrupedal stepping on a treadmill and in an open field environment to assess function in rodent models of neurologic disorders that impact motor activity This novel approach was validated using, a neurologically intact cohort, a cohort with unilateral Parkinsonian motor deficits due to midbrain lesioning, and a cohort with complete hind limb paralysis due to T8 spinal cord transection. In the SCI cohort, lumbosacral epidural electrical stimulation (EES) was applied, with and without administration of the serotonergic agonist Quipazine, to enable hind limb motor functions following paralysis. The results presented herein demonstrate the MfBA is capable of integrating multiple metrics of motor activity in order to characterize relationships between EES inputs that modulate mono- and polysynaptic outputs from spinal circuitry which in turn, can be used to elucidate underlying electrophysiologic mechanisms of motor behavior by synchronizing these datasets to metrics of movement and behavior. These results also demonstrate that proposed MfBA is an effective tool to integrate biomechanical and electrophysiology metrics, synchronized to therapeutic inputs such as EES or pharmacology, during body weight supported treadmill or open field motor activities, to target a high range of variations in motor behavior as a result of neurological deficit at the different levels of CNS.

neuroscience↗