OBJECTIVE To study the protective effects of Schwann cell derived neurotrophic factor (SDNF) on motoneurons of spinal anterior horn from spinal root avulsion induced cell death. METHODS Twenty SD rats were made the animal model of C6.7 spinal root avulsion induced motoneuron degeneration, and SDNF was applied at the lesion site of spinal cord once a week. After three weeks, the C6.7 spinal region was dissected out for motoneuron count, morphological analysis and nitric oxide synthase (NOS) enzyme histochemistry. RESULTS 68.6% motoneurons of spinal anterior horn death were occurred after 3 weeks following surgery, the size of survivors was significantly atrophy and NOS positive neurons increased. However, in animals which received SDNF treatment, the death of motoneurons was significantly decreased, the atrophy of surviving motoneurons was prevented, and expression of NOS was inhibited. CONCLUSION SDNF can prevent the death of motoneurons following spinal root avulsion. Nitric oxide may play a role in these injury induced motoneuron death.
Objective To explore the changes of morphology and ventricornual motor neuronsin SD rats’ ventral horn of spinal cord after radiated as the therapy protocol for breast cancer, to discover the rule of radiationinduced injury of brachialplexus, and also if there exits the reversible conversion in neurons. Methods Twenty SD rats were selected. The left side of the rats was used as the radiation side, and the right side as the control side. The RIBPI animal models were established by divideddose of radiation. Using 2 Gy/time and 5 times/week, a total administered dose reached 30 Gy after 3 weeks. The behaviour of the rats was observed after radiation. At 3, 5, 7 and 9 weeks after the last radiation (n=4), the wet weights of biceps brachii muscle, upperlimb circumference and compound action potential were examined; the pathological changes of biceps brachiimuscle, the morphological changes, counts of the motor neurons in ventral horn and axons of bilateral spinal cord were observed by HE staining, argentums staining and toluidine blue staining. Results The rats showed lameness and a “claw hand” 3 weeks after radiation. Compared with control side, thewet weights of biceps brachii muscle and upperlimb circumference were significantly reduced, meanwhile, the compound action potential significantly decreased, and its latent period was also significantly prolonged 3, 5, 7 and 9 weeks (Plt;0.05). The histological observation: Musculocutaneous nerve showed decreased medullated fibers, heterogeneous ditribution and decreased density, thin myelin sheath, damaged nerve structure and collagen hyperplasia; biceps brachii muscle showed degeneration, fiber breakage and inflammatory cell infiltration; The account of motor neurons in ventral horn was significantly decreased in the radiation side with time extending, the sign of cell death, such as, the neurons crimple, and karyolysis were observed(Plt;0.05). Conclusion Large dose of X-ray can inducedbrachial plexus injury, and the lameness, a “claw hand”, biceps brachii muscle atrophy and the compound action potential abnormality. The account of motor neurons in ventral horn was significantly decreased. The motor neurons showed oxonal degeneration and myelinec degeration.
Objective To investigate the distribution of rats’ pelvic muscles motoneurons innervated by artifical somatic-autonomic reflex arc. Methods Thirty-five SD rats were randomly divided into normal group (n=10) and model group (n=25). The rats in the normal group were given no treatment. In the normal group, the artifical somatic-autonomic reflex arc was established. Six months after establishing the model, external urethral sphincter (EUS), ischiocavernosus (IC), bulbocavernosus (BS) and external anal sphincter (EAS) of the rats in normal group(n=10) and of the rats in model group A (n=20) were injected with fluorogold (FG). The reversal neural tracing was done. FG positive neural cells were observedby fluorescent microscope. Malt agglutinator binding horseradish peroxidase (WGA-HRP) was injected into L4 spinal cord of the rats in model group B (n=5) as the anterograde tracer. After being treated with TMB-HRP reaction, the axon endings in the neuromuscular junction in pelvic striated muscles (EUS, IC, BS, EAS) were investigated with light microscopes. Results In normal group, EUS and IC injections resulted in transport of FG to neurons in the dorsolateral nucleus (DL) of the ventral horn of the L5～S1, and BS and EAS in the dorsomedial nucleus (DM) of ventral horn in the L5～S1. In the model group A, EUS, IC, BS andEAS injections resulted in transport of FG to neurons in the left ventral horn in the L4. In model group B, after WGA-HRP was injected into the L4 left ventral horn, HRP positive axon terminals were observed in the EUS, IC, BS and EAS. Conclusion In the normal rats, the pelvic striated muscles motoneurons locate in the ventral horn of L5～S1. In the model rats, the pelvic striated muscles motoneurons innervated by artificial somatic-autonomic reflex arc locate in the ventral horn of the L4. After the artificial somaticautonomic reflex arc is established, the isomerous nerve fiber innervates EUS, IC, BS and EAS.
Objective To research the protective effects of different allogeneic cells injected into denervated muscles on ventricornual motor neuron. Methods Thirty-six adult female SD rats, weighting 120-150 g, were individed into four groups randomly and each group had nine. Left ischiadic nerves of all the SD rats, which were cut down on germfree conditions,were operated by primary suture of epineurium. Different cells were injected into the triceps muscles of calf in each group after operation with once a week for 4 weeks:1 ml Schwann cells (1×106/ml) in group A, 1 ml mixed cells ofSchwann cells and myoblast cells (1∶1,1×106/ml) in group B, 1 ml extract from the mixed cells of Schwann cells, myoblast cells and endotheliocytes (1∶1∶1,1×106/ml)in group C,and 1 ml culture medium without FCS as control group(group D). The observation of enzymohistochemistry and C-Jun expression in the ventricornual motor neuron was made after three months of operation. Results After 3 months of operation, the expressions of C-Jun in groups A, B and C were superiorto that in group D; the number of neuron was more than that of group D. The expressions of C-Jun in the ventricornual motor neuron were as follows: 128.591±0.766 in group A, 116.729±0.778 in group B, 100.071±2.017 in group C and 144.648±2.083 in group D; showing statistically significant difference between groupsA, B, C and D(P＜0.01). Enzymohistochemistry showed the well outlined and wellstacked cell body of neuron in groups A, B and C, and illdefined boundary of cytoplasm and nucleus. There was statistically significant defference in enzyme activity of the ventricornual motor neuron between groups(P＜0.01). Conclusion All of the Schwann cells,mixed cells of Schwann cells with myoblast cells,and the extract from Schwann cells, myoblast cells and endotheliocytes can protect the ventricornual motor neuron. And the protectiveeffect of the extract from Schwann cells, myoblast cells and endotheliocytes is superior to that of Schwann cells and mixed cells.
OBJECTIVE Following the delayed repair of peripheral nerve injury, the cell number of anterior horn of the spinal cord and its ultrastructural changes, motorneuron and its electrophysiological changes were investigated. METHODS In 16 rabbits the common peroneal nerves of both sides being transected one year later were divided into four groups randomly: the degeneration group and regeneration of 1, 3 and 5 months groups. Another 4 rabbits were used for control. All transected common peroneal nerves underwent epineural suture except for the degeneration group the electrophysiological examination was carried out at 1, 3 and 5 months postoperatively. Retrograde labelling of the anterior horn cells was demonstrated and the cells were observed under light and electronmicroscope. RESULTS 1. The number of labelled anterior horn cell in the spinal cord was 45% of the normal population after denervation for one year (P lt; 0.01). The number of labelled cells increased steadily from 48% to 57% and 68% of normal values at 1, 3 and 5 months following delayed nerve repair (P lt; 0.01). 2. The ultrastructure of the anterior horn cells of the recover gradually after repair. 3. With the progress of regeneration the latency become shortened, the conduction velocity was increased, the amplitude of action potential was increased. CONCLUSION Following delayed repair of injury of peripheral nerve, the morphology of anterior horn cells of spinal cord and electrophysiological display all revealed evidence of regeneration, thus the late repair of injury of peripheral nerve was valid.
Objective To investigate the expression and clinical value of long chain non-coding RNA nicotinamide nucleotide hydrogenase antisense RNA1 (LncRNA NNT-AS1), motor neuron and pancreas homeobox protein 1 antisense RNA1 (MNX1-AS1) in lung cancer patients. Methods This study selected 128 patients diagnosed with lung cancer admitted to The Third Medical Center of the General Hospital of the People’s Liberation Army from April 2020 to April 2021 as a cancer group. During the same period, 128 patients with benign pulmonary nodules were regarded as a benign group, and 128 healthy individuals who underwent physical examination were selected as a control group. Quantitative real-time polymerase chain reaction (qRT-PCR) was applied to detect the levels of LncRNA NNT-AS1 and MNX1-AS1 in serum. A three-year follow-up was conducted on all lung cancer patients, with 52 patients in the death group and 76 patients in the survival group. Receiver operator characteristic (ROC) curve was applied to analyze the diagnostic value of serum LncRNA NNT-AS1 and MNX1-AS1 for the occurrence of lung cancer and their predictive value for prognosis. Results Compared with the control group, the serum levels of LncRNA NNT-AS1 and MNX1-AS1 were obviously increased in the benign group and the cancer group (P<0.05). Compared with the benign group, the levels of LncRNA NNT-AS1 and MNX1-AS1 in serum of the cancer patients were obviously increased (P<0.05). The area under ROC curve (AUC) of serum LncRNA NNT-AS1 combined with MNX1-AS1 for the diagnosis of lung cancer was higher than that of LncRNA NNT-AS1 and MNX1-AS1 alone (ZLncRNA NNT-AS1~LncRNA NNT-AS1+MNX1-AS1=2.496, P=0.013; ZMNX1-AS1~LncRNA NNT-AS1+MNX1-AS1=2.831, P=0.007). The levels of LncRNA NNT-AS1 and MNX1-AS1 were related to tumor differentiation, clinical stage, and lymph node metastasis (P<0.05). Compared with the survival group, the serum levels of LncRNA NNT-AS1 and MNX1-AS1 in the death group were obviously increased (P<0.05). The AUC of combined prediction for lung cancer prognosis by serum LncRNA NNT-AS1 and MNX1-AS1 was higher than that predicted by LncRNA NNT-AS1 and MNX1-AS1 alone (ZLncRNA NNT-AS1~LncRNA NNT-AS1+MNX1-AS1=2.539, P=0.011; ZMNX1-AS1~LncRNA NNT-AS1+MNX1-AS1=3.377, P=0.001). Conclusion LncRNA NNT-AS1 and MNX1-AS1 are highly expressed in serum of lung cancer patients, and both have certain value in diagnosis and prognosis evaluation of lung cancer.
Objective To review research progress of the relation between glial cell line-derived neurotropic factor (GDNF) and motoneuron development and motoneuron disease. Methods The recent articles on GDNF and motonerons were extensively reviewed. The molecular structure, the mode of action and the route of administration of GDNF were investigated. Results GDNF plays extensive roles in the development anddisease of motoneuron. GDNF might regulate the development of the motonerons of the spinal cord to some extent and also save the injured motoneurons. Conclusion GDNF has a potential clinical value and inestimable futurein the treatment of motoneuron diseases.
The translation and translation regulation of RNA in eukaryotic cells have a significant impact on cellular gene expression and maintenance of proteomic homeostasis. Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that affects upper and lower motor neurons and leads to muscle weakness and atrophy. More and more studies have found RNA translation abnormalities in ALS. This article provides an overview of RNA translation and regulation in eukaryotic cells under physiological and stress conditions, and explores the relationship between four different ALS-related genes and translation abnormalities, providing new ideas for the treatment of ALS.
Objective To investigate the survival effect and reaction mechanismsof motor neurons after reimplantation of the avulsed root into the spinal cord,and to observe the survival and differentiation in the spinal cord after brachial plexus roots avulsion. Methods Thirty adult Wistar rats were randomly devided into the control group and the experimental group (n=15). Laminectomy of C4-6 was performed via a posterior approach. The ventral and dorsal roots of C5，6 were both avulsed from the spinal cord outside the dura mater and within the vertebral canal.For the experimental group, the ventral root of C6 wasreimplanted into the ventralhorn under microscope. The dorsal root was left. The ventral and dorsal roots of C5 were placed inside the nearby muscles. For the control group, the ventral and dorsal roots of both C5 and C6 were placed inside the nearby muscles. At 2, 4, 6, 8, 12 weeks postoperatively, the C6 spinal cord was stained with HE. The changes of the number and morphology of motor neurons were observed onHEstained sections. The C6 spinal nerve root was stained with silver nitrate, andthe regeneration of nerve fiber was observed. Results All rats were recovered well and their wounds were healed at primary stage. The gross observation showed that the avulsed nerve roots in control group adhered to adjacent muscles, however the one in experimental groups which had been implanted into spinal cord adhered to scar tissues and were not separated from spinal cord. At each time point postoperatively, the HEstained transverse sections showed that the number of motor neurons decreased significantly with soma swollen and atrophied, Nissle bodies decreased or disappeared. The survival rates of motor neurons in the control group were 60.9％±5.8%,42.3％±3.5％,30.6％±6.1％27.5％±7.9％ and 20.4％±6.8％ respectively；in the experimental group,the survival rates were 67.1％±7.4％,56.3％±4.6％,48.7％±8.8％,44.2％±5.5％ and 42.5％±8.3％ respectively. The survival rates of motor neurons in the experimental group was higher than those in the control group at all time points,showing statistically significant difference（Plt;0.01）.At 12 weeks postoperatively, thesilver nitrate stained specimen from the C6 nerve root showed regeneration of the motor neurons in the ventral horn into the reimplanted nerve root through axon in the experimental group,but the degeneration of the nerve fiber appeared and the number of the myelinated nerve fiber decreased in the control group. Conclusion Through reimplantationof the avulsed ventral nerve root into the ventral horn, degeneration of the motor neurons in the ventral horn can be reduced. After reimplantation of avulsed nerve root, there is axonal regrowth of motor neurons into the spinal nerve root and regeneration of the myelinated nerve fiber also appears.