Meta analysis of olfactory ensheathing cell transplantation promoting functional recovery of motor nerves in rats with complete spinal cord transection

OBJECTIVE： To evaluate the effects of olfactory ensheathing cell transplantation on functional recovery of rats with complete spinal cord transection. DATA SOURCES： A computer-based online search of Medline （1989-2013）, Embase （1989- 2013）, Cochrane library （1989-2013）, Chinese Biomedical Literature Database （1989-2013）, China National Knowledge Infrastructure （1989-2013）, VIP （1989-2013）, Wanfang databases （1989-2013） and Chinese Clinical Trial Register was conducted to collect randomized controlled trial data regarding olfactory ensheathing cell transplantation for the treatment of complete spinal cord transection in rats. SELECTION CRITERIA： Randomized controlled trials investigating olfactory ensheathing cell transplantation and other transplantation methods for promoting neurological functional recov- ery of rats with complete spinal cord transection were included in the analysis. Meta analysis was conducted using RevMan 4.2.2 software. MAIN OUTCOME MEASURES： Basso, Beattie and Bresnahan scores of rats with complete spinal cord transection were evaluated in this study. RESULTS： Six randomized controlled trials with high quality methodology were included. Meta analysis showed that Basso, Beattie and Bresnahan scores were significantly higher in the olfacto- ry ensheathing cell transplantation group compared with the control group （WMD = 3.16, 95% （21 （1.68, 4.65）; P 〈 0.00001）. CONCLUSION： Experimental studies have shown that olfactory ensheathing cell transplantation can promote the functional recovery of motor nerves in rats with complete spinal cord transection.

Stem cell transplantation for treating spinal cord injury A literature comparison between studies of stem cells obtained from various sources

OBJECTIVE： To identify global research trends of stem cell transplantation for treating spinal cord injury using a bibliometric analysis of the Web of Science. DATA RETRIEVAL： We performed a bibliometric analysis of data retrievals for stem cell transplantation for treating spinal cord injury from 2002 to 2011 using the Web of Science. SELECTION CRITERIA： Inclusion criteria： （a） peer-reviewed articles on stem cell transplantation for treating spinal cord injury that were published and indexed in the Web of Science; （b） type of articles： original research articles, reviews, meeting abstracts, proceedings papers, book chapters, editorial material, and news items; and （c） year of publication： 2002-2011. Exclusion criteria： （a） articles that required manual searching or telephone access; （b） documents that were not published in the public domain; and （c） a number of corrected papers from the total number of articles. MAIN OUTCOME MEASURES： （1） Annual publication output; （2） distribution according to country; （3） distribution according to institution; （4） distribution according to journals; （5） distribution according to funding agencies; and （6） top cited articles over the last 10 years. RESULTS： Bone marrow mesenchymal stem cells and embryonic stem cells have been widely used for treating spinal cord injury. In total, 191 studies of bone marrow mesenchymal stem cell transplantation and 236 studies of embryonic stem cell transplantation for treating spinal cord injury appeared in the Web of Science from 2002 to 2011, and almost half of which were derived from American or Japanese authors and institutes. The number of studies of stem cell transplantation for treating spinal cord injury has gradually increased over the past 10 years. Most papers on stem cell transplantation for treating spinal cord injury appeared in journals with a particular focus on stem cell research, such as Stem Cells and Cell Transplantation. Although umbilical cord blood stem cells and adipose-derived stem cells have been studied for treating spinal cord injury, the number of published papers was much smaller, with only 21 and 17 records, respectively, in the Web of Science. CONCLUSION： Based on our analysis of the literature and research trends, we found that stem cells transplantation obtained from various sources have been studied for treating spinal cord injury; however, it is difficult for researchers to reach a consensus on this theme.

A non-opioid pathway for dynorphin-caused spinal cord injury in rats

Intrathecal injection of dynorphin into rats via subarachnoid catheter induces damage to spinal cord tissue and motor function. Injection of the kappa opioid receptor antagonist nor-binaltorphine, or the excitatory amino acid N-methyl-D-aspartate receptor antagonist MK-801 into rats alleviated the pathological changes of dynorphin-caused spinal cord tissue injury and reduced the acid phosphatase activity in the spinal cord. The experimental findings indicate that there are opioid and non-opioid pathways for dynorphin-induced spinal cord injury, and that the non-opioid receptor pathway may be mediated by the excitatory amino acid N-methyl-D-aspartate receptor.

Kappa opioid receptor antagonist and N-methyl-D-aspartate receptor antagonist affect dynorphin-induced spinal cord electrophysiologic impairment

The latencies of motor- and somatosensory-evoked potentials were prolonged to different degrees, and wave amplitude was obviously decreased, after injection of dynorphin into the rat subarachnoid cavity. The wave amplitude and latencies of motor- and somatosensory-evoked potentials were significantly recovered at 7 and 14 days after combined injection of dynorphin and either the kappa opioid receptor antagonist nor-binaltorphimine or the N-methyl-D-aspartate receptor antagonist MK-801. The wave amplitude and latency were similar in rats after combined injection of dynorphin and nor-binaltorphimine or MK-801. These results suggest that intrathecal injection of dynorphin causes damage to spinal cord function. Prevention of N-methyl-D-aspartate receptor or kappa receptor activation lessened the injury to spinal cord function induced by dynorphin.

Chondroitinase ABC improves recovery of long sciatic nerve defects

Sciatic nerves from allogeneic Sprague-Dawley rats were pretreated with chondroitinase ABC and were used to bridge damaged sciatic nerves in Wistar rats. Chondroitin sulfate proteoglycans were removed from the chemically extracted acellular nerves. At 3 months after grafting, the footplate pinch test result was positive in the Wistar rats. Autotorny scores decreased, and increased muscular contraction tension appeared when triceps surae muscles were stimulated. In addition, the recovery rate of wet triceps surae muscle weight increased, and the distal segment of the chondroitinase ABC-treated graft exhibited Schwann cells next to the nerve fibers. These results suggested that chondroitinase ABC pretreatment enhanced repair of long nerve defects via acellular nerve grafting.