ISP and PAP4 peptides promote motor functional recovery after peripheral nerve injury

Both intracellular sigma peptide(ISP) and phosphatase and tensin homolog agonist protein(PAP4) promote nerve regeneration and motor functional recovery after spinal cord injury. However, the role of these two small peptides in peripheral nerve injury remains unclear. A rat model of brachial plexus injury was established by crush of the C6 ventral root. The rats were then treated with subcutaneous injection of PAP4(497 μg/d, twice per day) or ISP(11 μg/d, once per day) near the injury site for 21 successive days. After ISP and PAP treatment, the survival of motoneurons was increased, the number of regenerated axons and neuromuscular junctions was increased, muscle atrophy was reduced, the electrical response of the motor units was enhanced and the motor function of the injured upper limbs was greatly improved in rats with brachial plexus injury. These findings suggest that ISP and PAP4 promote the recovery of motor function after peripheral nerve injury in rats. The animal care and experimental procedures were approved by the Laboratory Animal Ethics Committee of Jinan University of China(approval No. 20111008001) in 2011.

Surgical intervention combined with weight-bearing walking training improves neurological recoveries in 320 patients with clinically complete spinal cord injury:a prospective self-controlled study

Although a large number of trials in the SCI field have been conducted,few proven gains have been realized for patients.In the present study,we determined the efficacy of a novel combination treatment involving surgical intervention and long-term weight-bearing walking training in spinal cord injury(SCI)subjects clinically diagnosed as complete or American Spinal Injury Association Impairment Scale(AIS)Class A(AIS-A).A total of 320 clinically complete SCI subjects(271 male and 49 female),aged 16–60 years,received early(≤7 days,n=201)or delayed(8–30 days,n=119)surgical interventions to reduce intraspinal or intramedullary pressure.Fifteen days post-surgery,all subjects received a weight-bearing walking training with the“Kunming Locomotion Training Program(KLTP)”for a duration of 6 months.The neurological deficit and recovery were assessed using the AIS scale and a 10-point Kunming Locomotor Scale(KLS).We found that surgical intervention significantly improved AIS scores measured at 15 days post-surgery as compared to the pre-surgery baseline scores.Significant improvement of AIS scores was detected at 3 and 6 months and the KLS further showed significant improvements between all pair-wise comparisons of time points of 15 days,3 or 6 months indicating continued improvement in walking scores during the 6-month period.In conclusion,combining surgical intervention within 1 month post-injury and weight-bearing locomotor training promoted continued and statistically significant neurological recoveries in subjects with clinically complete SCI,which generally shows little clinical recovery within the first year after injury and most are permanently disabled.This study was approved by the Science and Research Committee of Kunming General Hospital of PLA and Kunming Tongren Hospital,China and registered at ClinicalTrials.gov(Identifier:NCT04034108)on July 26,2019.

Spastin interacts with collapsin response mediator protein 3 to regulate neurite growth and branching

Cytoskeletal microtubule rearrangement and movement are crucial in the repair of spinal cord injury.Spastin plays an important role in the regulation of microtubule severing.Both spastin and collapsin response mediator proteins can regulate neurite growth and branching;however,whether spastin interacts with collapsin response mediator protein 3(CRMP3)during this process remains unclear,as is the mechanism by which CRMP3 participates in the repair of spinal cord injury.In this study,we used a proteomics approach to identify key proteins associated with spinal cord injury repair.We then employed liquid chromatography-mass spectrometry to identify proteins that were able to interact with glutathione S-transferase-spastin.Then,co-immunoprecipitation and staining approaches were used to evaluate potential interactions between spastin and CRMP3.Finally,we co-transfected primary hippocampal neurons with CRMP3 and spastin to evaluate their role in neurite outgrowth.Mass spectrometry identified the role of CRMP3 in the spinal cord injury repair process.Liquid chromatography-mass spectrometry pulldown assays identified three CRMP3 peptides that were able to interact with spastin.CRMP3 and spastin were co-expressed in the spinal cord and were able to interact with one another in vitro and in vivo.Lastly,CRMP3 overexpression was able to enhance the ability of spastin to promote neurite growth and branching.Therefore,our results confirm that spastin and CRMP3 play roles in spinal cord injury repair by regulating neurite growth and branching.These proteins may therefore be novel targets for spinal cord injury repair.The Institutional Animal Care and Use Committee of Jinan University,China approved this study(approval No.IACUS-20181008-03)on October 8,2018.

Parallelized volumetric fluorescence microscopy with a reconfigurable coded incoherent light-sheet array

Parallelized fluorescence imaging has been a long-standing pursuit that can address the unmet need for a comprehensive three-dimensional(3D)visualization of dynamical biological processes with minimal photodamage.However,the available approaches are limited to incomplete parallelization in only two dimensions or sparse sampling in three dimensions.We hereby develop a novel fluorescence imaging approach,called coded light-sheet array microscopy(CLAM),which allows complete parallelized 3D imaging without mechanical scanning.Harnessing the concept of an“infinity mirror”,CLAM generates a light-sheet array with controllable sheet density and degree of coherence.Thus,CLAM circumvents the common complications of multiple coherent light-sheet generation in terms of dedicated wavefront engineering and mechanical dithering/scanning.Moreover,the encoding of multiplexed optical sections in CLAM allows the synchronous capture of all sectioned images within the imaged volume.We demonstrate the utility of CLAM in different imaging scenarios,including a light-scattering medium,an optically cleared tissue,and microparticles in fluidic flow.CLAM can maximize the signal-to-noise ratio and the spatial duty cycle,and also provides a further reduction in photobleaching compared to the major scanning-based 3D imaging systems.The flexible implementation of CLAM regarding both hardware and software ensures compatibility with any light-sheet imaging modality and could thus be instrumental in a multitude of areas in biological research.