Genetic and clinical analysis of a novel GLB1 gene variant in a Chinese patient with GM1-gangliosidosis / 中华医学遗传学杂志

OBJECTIVE@#To explore the genotype-phenotype correlation of a case with GM1-gangliosidosis caused by compound heterogenic variants in GLB1.@*METHODS@#Genomic DNA was extracted from peripheral blood samples from the patient and her parents. Trio-based whole-exome sequencing (WES) was performed for the family and suspected mutation was verified by Sanger sequencing.@*RESULTS@#The proband, a 2-year-3-month old Chinese girl, presented with psychomotor deterioration, absent speech, intellectual disabilities and behavior problem. Trio-based WES has identified compound heterozygosity for 2 variants in the GLB1 gene: NM_000404.2:c.1343A>T, p.Asp448Val and c.1064A>C, p.Gln355Pro (GRCh37/hg19),which was inherited from the mother and father, respectively. Homozygous or compound heterozygous pathogenic variants in GLB1, encoding β-galactosidase, are responsible for GM1-gangliosidosis,an autosomal recessive lysosomal storage disorder characterized by variable degrees of neurodegeneration and skeletal abnormalities. The p.Asp448Val variant has been classified as pathogenic for GM1 gangliosidosis in medical literatures for the reason that functional studies demonstrated that expression of the p.Asp448Val variant in COS-1 cells resulted in no detectable β-galactosidase activity compared to wild type GLB1. The p.Gln355Pro variant has not been reported in literatures or database. The variant is highly conserved residue (PM1), and was not found in either the Genome Aggregation Database or the 1000 Genomes Project (PM2) and was predicted to have a deleterious effect on the gene product by multiple in silico prediction tools (PP3). Next, the β-galactosidase activity of the patient's peripheral blood leukocytes was determined by fluorescent method. The result was 0.0 nmol/mg. It showed that the p.Gln355Pro variant also resulted in loss of β-galactosidase activity, thus the variant was classified into clinical pathogenic variant.@*CONCLUSION@#Our study expands the mutational spectrum of the GLB1 gene and provides genetic counseling for the family.

Effects of ganglioside G(M1) and erythropoietin on spinal cord lesions in rats: functional and histological evaluations

OBJECTIVE: To evaluate the functional and histological effects of ganglioside G(M1) and erythropoietin after experimental spinal cord contusion injury. METHODS: Fifty male Wistar rats underwent experimental spinal cord lesioning using an NYU-Impactor device and were randomly divided into the following groups, which received treatment intraperitoneally. The G(M1) group received ganglioside G(M1) (30 mg/kg); the erythropoietin group received erythropoietin (1000 IU/kg); the combined group received both drugs; and the saline group received saline (0.9%) as a control. A fifth group was the laminectomy group, in which the animals were subjected to laminectomy alone, without spinal lesioning or treatment. The animals were evaluated according to the Basso, Beattie and Bresnahan (BBB) scale, motor evoked potential recordings and, after euthanasia, histological analysis of spinal cord tissue. RESULTS: The erythropoietin group had higher BBB scores than the G(M1) group. The combined group had the highest BBB scores, and the saline group had the lowest BBB scores. No significant difference in latency was observed between the three groups that underwent spinal cord lesioning and intervention. However, the combined group showed a significantly higher signal amplitude than the other treatment groups or the saline group (p<0.01). Histological tissue analysis showed no significant difference between the groups. Axonal index was significantly enhanced in the combined group than any other intervention (p<0.01). CONCLUSION: G(M1) and erythropoietin exert therapeutic effects on axonal regeneration and electrophysiological and motor functions in rats subjected to experimental spinal cord lesioning and administering these two substances in combination potentiates their effects.

The effect of monosialoganglyoside (GM-1) administration in spinal cord injury / Efeito da administração do monosialogangliosídeo (GM-1) no trauma raquimedular

Objetivo: Avaliar o efeito do uso de monosialogangliosídeo (GM-1) nospacientes vítimas de trauma raquimedular atendidos em nosso serviço que não foram tratados com metilprednisolona. Métodos: Trinta pacientes vítimas de trauma raquimedular agudo foram divididos randomicamente em dois grupos. No Grupo 1, os pacientes receberam200 mg de GM-1 no atendimento inicial e a partir daí receberam 100mg endovenoso por dia durante 30 dias e o Grupo 2 (controle) recebeu soro fisiológico. Os pacientes foram avaliados periodicamente(com 6 semanas, 6 meses, um ano e 2 anos), utilizando-se a padronização de avaliação neurológica da American Spinal Injuty Association/International Spinal Cord Society. Resultados: A análise estatística comparativa dos índices motores, sensitivo para dor e sensitivo paratato de acordo com a padronização da ASIA/ISCOS mostrou que nas avaliações com 6 semanas, 6 meses e 2 anos os pacientes do Grupo GM-1 apresentaram índices superiores em relação ao grupo controle em relação a sensibilidade para dor e tato, não havendo diferença estatisticamente significativa em relação ao índice motor. Conclusão: A avaliação funcional demonstrou melhora nos índices sensitivos dos pacientes tratados com GM1 após lesão medularpós-traumática em relação aos pacientes que receberam placebo.Nível de Evidência IV, Estudo Prospectivo de Série de Casos.

Objective: To evaluate the effect of monosialoganglioside (GM-1)in spinal cord trauma patients seen in our service who have notbeen treated with methylprednisolone. Methods: Thirty patientswith acute spinal cord trauma were randomly divided into twogroups. In Group 1, patients received 200 mg GM-1 in the initialassessment and thereafter received 100 mg intravenous per dayfor 30 days and Group 2 (control) received saline. Patients wereevaluated periodically (at 6 weeks, 6 months, one year and twoyears), using a standardized neurological assessment of theAmerican Spinal Injury Association / International Spinal CordSociety. Results: The comparative statistical analysis of motorindices, sensitive indices for pain and touch according to thestandardization of ASIA / ISCOS showed that the assessmentsat 6 weeks, 6 months and 2 years, GM-Group 1 patients hadhigher rates than the control group regarding sensitivity to painand touch, with no statistically significant difference from themotor index. Conclusion: The functional assessment showedimprovement in the sensitive indices of patients treated withGM1 after post-traumatic spinal cord injury compared to patientswho received placebo. Level of Evidence IV, Prospective CaseStudies Series.

The role of pharmacotherapy in modifying the neurological status of patients with spinal and spinal cord injuries / O papel da farmacoterapia na modificação do estado neurológico de traumatizados vértebro-medulares

The aim here was to conduct a review of the literature on pharmacological therapies for modifying the neurological status of patients with spinal cord injuries. The PubMed database was searched for articles with the terms "spinal cord injury AND methylprednisolone/GM1/apoptosis inhibitor/calpain inhibitor/naloxone/tempol/tirilazad", in Portuguese or in English, published over the last five years. Older studies were included because of their historical importance. The pharmacological groups were divided according to their capacity to interfere with the physiopathological mechanisms of secondary injuries. Use of methylprednisolone needs to be carefully weighed up: other anti-inflammatory agents have shown benefits in humans or in animals. GM1 does not seem to have greater efficacy than methylprednisolone, but longer-term studies are needed. Many inhibitors of apoptosis have shown benefits inin vitro studies or in animals. Naloxone has not shown benefits. Tempol inhibits the main consequences of oxidation at the level of the spinal cord and other antioxidant drugs seem to have an effect superior to that of methylprednisolone. There is an urgent need to find new treatments that improve the neurological status of patients with spinal cord injuries. The benefits from treatment with methylprednisolone have been questioned, with concerns regarding its safety. Other drugs have been studied, and some of these may provide promising alternatives. Additional studies are needed in order to reach conclusions regarding the benefits of these agents in clinical practice.

O objetivo deste trabalho foi fazer uma revisão da literatura sobre a terapia farmacológica para a modificação do estado neurológico de traumatizados vértebro-medulares. Foi feita uma na base de dados Pubmed por artigos com os termos "spinal cord injury AND methylprednisolone/GM1/apoptosis inhibitor/calpain inhibitor/naloxone/tempol/tirilazad", em português ou em inglês, publicados nos últimos cinco anos. Trabalhos mais antigos foram incluídos pela sua importância histórica. Os grupos farmacológicos foram divididos em função da sua capacidade para interferir nos mecanismos fisiopatológicos da lesão secundária. O uso de metilprednisolona deve ser cuidadosamente ponderado. Outros anti-inflamatórios mostraram benefícios em humanos ou em animais. O GM1 não aparenta ter maior eficácia do que a MP, mas estudos em mais longo prazo são necessários. Muitos inibidores da apoptose têm mostrado benefício em estudos in vitro ou em animais. A naloxona não deu mostras de benefício. O tempol inibe as principais consequências da oxidação no nível da medula e outros fármacos antioxidantes aparentam ter um efeito superior ao da metilprednisolona. É urgente encontrar novos tratamentos que melhorem o estado neurológico dos traumatizados vértebro-medulares. Os benefícios do tratamento com metilprednisolona têm sido questionados, há preocupações em relação à sua segurança. Outros fármacos têm sido estudados, podem alguns deles ser opções promissoras. Estudos adicionais são necessários para tirar conclusões sobre o benefício desses agentes na prática clínica.

Monossialogangliosídeo transdérmico com laser no tratamento de lesão medular espinal de ratos / Transdermal monosialoganglioside with laser in the treatment of spinal cord lesion in rats

Objetivos: Avaliar os efeitos de monossialogangliosídeos (GM1) administrados com laser por via transdérmica na recuperação da lesão da medula espinal de ratos. Métodos: Quarenta ratos Wistar machos foram submetidos a contusão da medula espinal usando NYU Impactor. No Grupo 1, os ratos receberam 0,2 ml de solução salina diária por via intraperitoneal; no Grupo 2, GM1 foi administrada intraperitonealmente em concentração de 30 mg/kg por dia; no Grupo 3, os ratos foram tratados diariamente com o laser a baixa temperatura sobre a pele, e no Grupo 4, a sessão de laser diária também continha GM1. Todos os grupos foram tratados durante 42 dias. Os animais foram avaliados pela escala funcional de Basso, Baettie e Bresnahan (BBB) nos dias 7, 14, 21, 28, 35 e 42 após a lesão, e por histopatologia e potencial motor evocado 42 dias depois da lesão. Resultados: Os animais do Grupo 4 apresentaram escores BBB mais elevados em comparação com os outros grupos. Não houve diferenças entre os grupos ou nas comparações ao longo do tempo. A avaliação histológica não mostrou diferenças, e tampouco foram encontradas diferenças significativas no potencial evocado. Conclusão: A GM1 associada ao uso de laser a baixa temperatura não mostra resultados superiores no tratamento de lesões da medula espinal de ratos. Nível de Evidência I, Experimental, Estudo Controlado de Animais.

Objectives: To evaluate the effects of monosialoganglioside (gm1) administered transdermally with laser in the recovery of spinal cord injury in rats. methods: forty male wistar rats underwent spinal cord contusion using the nyu impactor. in group 1, the rats received 0,2 ml of saline intraperitoneally daily; in group 2, GM1 was administered intraperitoneally at a concentration of 30 mg/kg per day; in group 3, rats were treated daily with laser at low temperature on the skin, and in group 4, the daily laser session also contained gm1. all the groups were treated for 42 days. the animals were evaluated by the Basso, Baettie and Bresnahan (BBB) functional scale on days 7, 14, 21, 28, 35 and 42 after the injury, and by histopathology and motor evoked potential after 42 days of injury. Results: the animals in group 4 had higher BBB scores compared with the other groups. there were no differences between the groups, or in the comparisons over time. Histological evaluation showed no differences, and no differences were found in the motor evoked potential tests either. conclusion: gm1 associated with the use of low-temperature laser shows no superior functional, neurological or histological results in the treatment of spinal cord lesions in rats. Evidence Level I, Experimental, Controlled, Animal Study.

GM1 improves neurofascin155 association with lipid rafts and prevents rat brain myelin injury after hypoxia-ischemia

White matter injury characterized by damage to myelin is an important process in hypoxic-ischemic brain damage (HIBD). Because the oligodendrocyte-specific isoform of neurofascin, neurofascin 155 (NF155), and its association with lipid rafts are essential for the establishment and stabilization of the paranodal junction, which is required for tight interaction between myelin and axons, we analyzed the effect of monosialotetrahexosyl ganglioside (GM1) on NF155 expression and its association with lipid rafts after HIBD in Sprague-Dawley rats, weighing 12-15 g, on day 7 post-partum (P7; N = 20 per group). HIBD was induced on P7 and the rats were divided into two groups: one group received an intraperitoneal injection of 50 mg/kg GM1 three times and the other group an injection of saline. There was also a group of 20 sham-operated rats. After sacrifice, the brains of the rats were removed on P30 and studied by immunochemistry, SDS-PAGE, Western blot analysis, and electron microscopy. Staining showed that the saline group had definite rarefaction and fragmentation of brain myelin sheaths, whereas the GM1 group had no obvious structural changes. The GM1 group had 1.9-2.9-fold more GM1 in lipid rafts than the saline group (fraction 3-6; all P < 0.05) and 0.5-2.4-fold higher expression of NF155 in lipid rafts (fraction 3-5; all P < 0.05). Injection of GM1 increased the content of GM1 in lipid rafts as well as NF155 expression and its lipid raft association in HIBD rat brains. GM1 may repair the structure of lipid rafts, promote the association of NF155 (or other important proteins) with lipid rafts, stabilize the structure of paranodes, and eventually prevent myelin sheath damage, suggesting a novel mechanism for its neuroprotective properties.

Modulation of ROS production in human leukocytes by ganglioside micelles

Recent studies have reported that exogenous gangliosides, the sialic acid-containing glycosphingolipids, are able to modulate many cellular functions. We examined the effect of micelles of mono- and trisialoganglioside GM1 and GT1b on the production of reactive oxygen species by stimulated human polymorphonuclear neutrophils using different spectroscopic methods. The results indicated that exogenous gangliosides did not influence extracellular superoxide anion (O2.-) generation by polymorphonuclear neutrophils activated by receptor-dependent formyl-methionyl-leucyl-phenylalanine. However, when neutrophils were stimulated by receptor-bypassing phorbol 12-myristate 13-acetate (PMA), gangliosides above their critical micellar concentrations prolonged the lag time preceding the production in a concentration-dependent way, without affecting total extracellular O2.- generation detected by superoxide dismutase-inhibitable cytochrome c reduction. The effect of ganglioside GT1b (100 µM) on the increase in lag time was shown to be significant by means of both superoxide dismutase-inhibitable cytochrome c reduction assay and electron paramagnetic resonance spectroscopy (P < 0.0001 and P < 0.005, respectively). The observed phenomena can be attributed to the ability of ganglioside micelles attached to the cell surface to slow down PMA uptake, thus increasing the diffusion barrier and consequently delaying membrane events responsible for PMA-stimulated O2.- production.

Ganglioside GM1 (porcine) ameliorates paclitaxel-induced neuropathy in rats.

BACKGROUND: Paclitaxel, an anti-neoplastic agent effective against several solid tumors, has several side effects including peripheral neuropathy. So far, there are no effective treatments for this complication. Monosialic acid ganglioside (GM1) has been shown to protect neurons against injuries and degeneration. However, its efficacy in the treatment of paclitaxel-induced neuropathy has not been verified. OBJECTIVE: To evaluate the effect of porcine GM1 on neurophysiological abnormalities in rats receiving paclitaxel. MATERIAL AND METHOD: Fifty-four Wistar rats were divided into control, vehicle for paclitaxel (Cremophor EL), paclitaxel, and paclitaxel + GM1 groups. Paclitaxel 16 mg/kg/week for five consecutive weeks was given intraperitoneally. Treatment with 30 mg/kg 5 days per week of GM1 was started 3 days prior to the first dose and continued until 3 days after the last dose of paclitaxel. Tail and hind paw thermal thresholds including tail motor nerve conduction velocity (MNCV) were measured prior to and after the start of treatments. Histopathology of the sciatic nerve was also examined. RESULTS: Paclitaxel alone induced thermal hypoalgesia and reduced tail MNCV Less severe abnormalities were also found with the vehicle. GM1 appeared to prevent the development of hypoalgesia and ameliorated the decreased MNCV without any evidence of Guillain-Barre Syndrome. Mild endoneurial edema and axonal degeneration in the sciatic nerve sections were seen in paclitaxel treated rats. Microtubule accumulation and activated Schwann cell were also presented in the paclitaxel treated groups. CONCLUSION: These data suggest that porcine GM1 may be useful in the prevention and treatment of paclitaxel-induced neuropathy. However the adverse effect of Cremophor EL should be of concern.

Estudo dos efeitos do monossialogangliosídio (GM1) e da câmara de oxigenoterapia hiperbárica na lesão medular aguda em ratos / Experimental study with GM1 ganglioside and hyperbaric oxygenation in spinal cord injury in rats

O objetivo deste trabalho foi avaliar os efeitos do monossialogangliosídio (GM1), da câmara de oxigenoterapia hiperbárica e de ambos no tratamento da lesão medular experimental em ratos. Trinta e dois ratos Wistar com lesão medular foram divididos em 4 grupos: um grupo recebeu o monossialogangliosídio (GM1), um segundo foi submetido à oxigenoterapia hiperbárica, um terceiro recebeu os dois tratamentos e um quarto não recebeu tratamento (controle). Não houve diferença significativa entre os grupos na análise histológica, em todas as variáveis (necrose, hemorragia, hiperemia e degeneração cística, p>0,06). Também não houve nenhuma diferença na comparação entre os lados direito e esquerdo nos testes funcionais (p>0,06 para todos). Não foram encontradas diferenças nos testes motores, na comparação entre os grupos após 2, 7 21 e 28 dias de lesão medular. Mas, na avaliação após 14 dias, o Grupo 3, o qual recebeu a terapia combinada, mostrou um escore BBB significantemente maior que os outros grupos (p=0,015). Na avaliação de 28 dias, houve uma tendência dos Grupos 1 (GM1) e 3 (terapia combinada) apresentarem um escore BBB maior que o do Grupo 4 (controle), embora sem significância estatística (p=0,057). Concluiu-se que, quanto aos índices motores, a utilização do GM-1 tem efeito benéfico, embora sem diferença estatisticamente significante e que o efeito benéfico do GM-1 é antecipado através da utilização concomitante da oxigênio terapia hiperbárica.

The objectives were to evaluate the effect of GM1 ganglioside, hyperbaric oxygen, and both in combination, in the treatment of experimental spinal cord lesions in rats. Thirty-two Wistar rats with spinal cord lesions were divided into four groups: one group received GM1 ganglioside, one was submitted to hyperbaric oxygen therapy, the third received both treatments, and the fourth received no treatment (control). There were no significant differences between the groups in the histological analysis, for any of the variables (necrosis, hemorrhage, hyperemia, cystic degeneration, p > 0.06). Neither were there any significant differences in the comparison of left and right sides in the functional tests (p > 0.06 for all). No significant differences were found in the locomotor ratings, in the comparison of groups at 2 days, 7 days, 21 days and 28 days after the surgical procedure. However, in the evaluation on day 14, Group 3, which received the combined therapy, showed a significantly higher BBB score than the other groups (p = 0.015). In the evaluation on day 28, there was a trend to Group 1 (GM1) and 3 (combined therapy) showed a higher BBB score than the group 4 (control), but with no significance (p=0,057). In conclusion, the is a benefit in the use of GM1 ganglioside, but with no significance and the therapeutic effect of GM1 in locomotor evaluation of rats submitted to spinal cord lesion is anticipated by hyperbaric oxygen therapy.

Effects of ganglioside 1 and nerve growth factor on the proliferation of neural stem cells in vitro / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the effects of ganglioside 1 (GM1) and nerve growth factor (NGF) on neural stem cells (NSCs) proliferation in vitro.</p><p><b>METHODS</b>NSCs were isolated and cultured in vitro. NSCs were cultured in the medium containing epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) or without the two agents. Different concentrations of GM1 and NGF were added into the two different medium. MTT and cell ball counting methods were used to ascertain the proliferation of NSCs. Immunohistochemical technology was used to observe the effect of GM1 and NGF on the proliferation of NSCs.</p><p><b>RESULTS</b>High concentrations of GM1 (100 ng/L and 200 ng/L) promoted significantly the proliferation of NSCs in the medium containing EGF and bFGF (p<0.05). In the differentiation medium containing serum but no EGF and bFGF, NSCs proliferation increased with increasing concentration of GM1; the proportion of neurons and gliacytes increased with increasing concentration of NGF.</p><p><b>CONCLUSIONS</b>High concentration of GM1 can promote NSCs proliferation and NGF can promote NSCs differentiation.</p>

Effects of methylprednisolone and ganglioside GM-1 on a spinal lesion: a functional analysis

OBJECTIVES: The pharmacological effects of methylprednisolone (MP) and ganglioside GM-1 on spinal injuries have been thoroughly investigated, but only a few studies have evaluated the interaction between these two drugs. METHODS: Twenty-four Wistar rats were subjected to contusive injury of the spinal cord produced by the NYU system. These animals were divided into four groups: group I was injected with MP; group II was injected with GM-1; group III was injected with MP together with GM-1; and group control received physiological serum. The animals were evaluated with regard to their recovery of locomotive function by means of the BBB test on the second, seventh and fourteenth days after receiving the contusive injury to the spinal cord. They were sacrificed on the fourteenth day. RESULTS: This study demonstrated that the MP and GM-1 groups presented functional results that were better than those of the control group, although the enhanced recovery of group II (GM-1) relative to the control group was not statistically significant (p>0.05). The most notable recovery of locomotive function was observed in the group that received MP alone (p<0.05). The group that received MP together with GM-1 presented results that were better than those of the control group (p<0.05). CONCLUSION: Administration of methylprednisolone alone or with GM-1 was shown to be effective for recovery of locomotive function. Combined administration of these drugs resulted in better outcomes than administration of methylprednisolone alone.

Role of lipid raft in assembly of human herpesvirus 6 / 病毒学报

To explore the role of lipid raft in assembly of human herpesvirus 6, the HHV-6 GS strain was applied to infect the HSB2 cells and then the lipid raft composition was extracted from the cells with non-ionic detergent Triton-X 100. The relationship between the HHV-6 envelope glycoprotein and lipid raft was analyzed by Western Blot. Immunofluorescence double-staining was used to study the colocalization of the HHV-6 glycoprotein B(gB) with GPI anchored protein CD59 and ganglioside GM respectively. HHV-6 envelope glycoprotein B, H, L, Q1 and Q2 (gB, gH, gL, gQ1 and gQ2) were all existed in the lipid raft. Moreover, CD59 and HHV-6 envelope glycoprotein B showed the same localization through the confocal microscope. We concluded the lipid raft provided the platform for HHV-6 assembly. This is the first report concerning to the role of lipid raft in assembly of human Herpesvirus 6.

Comparative study on the role of parent Campylobacter jejuni and galE mutant in inducing experimental peripheral nerve damage / 中华儿科杂志

<p><b>OBJECTIVE</b>A comparative study on the role of Campylobacter jejuni (CJ) HB9313 and galE mutant in inducing experimental sciatic nerve damage was conducted in guinea pigs in order to explore whether CJ lipo-oligosaccharide (LOS) is critical component associated with peripheral nerve lesions and find experimental evidence for the presumption of molecular mimicry on the pathogenesis of Guillain-Barre syndromes (GBS) with CJ antecedent infection.</p><p><b>METHODS</b>A total of 32 guinea pigs were randomly divided into four groups: parental strain group (n = 10), galE mutant group (n = 10), control group (n = 6) and PBS group (n = 6), and immunized with the whole cell antigens of CJ HB9313 with Freund's adjuvant (FA), the whole cell antigens of galE mutant (without ganglioside-like structure) with FA, PBS with FA, and PBS alone, respectively. Enzyme-linked immunosorbent assay (ELISA) was employed to detect anti-LOS and anti-ganglioside GM1 antibodies in sera of these animals, and comparative morphologic studies of pathologic changes were carried out on the sciatic nerves, including examination of teasing fibers, examination of semithin sections made from epon-embedded tissue blocks under light microscope and transmission electron microscope.</p><p><b>RESULTS</b>ELISA results indicated that after immunization, the levels of anti-LOS IgG antibody were significantly elevated in animals from parental strain group and galE mutant group as compared with those before immunization (P < 0.01). No statistically significant difference was found between the two groups. However, the mean optical densities (ODs) of IgG antibody against GM1 at 14 and 28 day after immunization, in parental strain group, were 0.661 +/- 0.290 and 0.984 +/- 0.025, respectively, significantly higher than those of galE mutant group, which were 0.193 +/- 0.078 and 0.180 +/- 0.063 (P < 0.01). The results of morphologic examination on sciatic nerves showed that for teased-fiber study, incidence of pathologic abnormalities of teased fibers from animals of galE mutant group was 4.9% (98/2000), significantly lower than that from parental strain group, which was 16% (320/2000), characterized by predominantly axonal degeneration. The difference between them was highly significant statistically (P < 0.01). Examination of semithin sections of sciatic nerves also revealed that obvious pathological changes occurred in the animals from parental strain group, while only minimal abnormalities could be seen from galE mutant group, there was a significant differences between them (P < 0.01). In parental strains group, the predominant pathologicanl change was axonal degeneration with considerable variation in severity. These morphologic changes were confirmed by electron microscopy.</p><p><b>CONCLUSION</b>Compared with parental strain, galE mutant without ganglioside-like structure no longer could induce anti-GM1 antibodies, nor induce obvious immune damage of peripheral nerves in experimental guinea pigs. The results of this study provide a strong support to the hypothesis of molecular mimicry as a pathogenesis in patients with GBS following CJ antecedent infection.</p>

Immunopathological evidence of terminal residues containing sialic acid in Campylobacter jejuni lipopolysaccharide as the critical antigen to induce peripheral neuropathy / 中华儿科杂志

<p><b>OBJECTIVE</b>To explore the important role of the terminal residues containing sialic acid (SA) in Campylobacter jejuni (CJ) lipopolysaccharide (LPS) as the critical antigen to induce nerve damage, and also to identify immunopathological evidence for the hypothesis of molecular mimicry and cross-immunity between CJ LPS and gangliosides.</p><p><b>METHODS</b>A mutant of Pen O:19 CJ with neuB1 gene inactivated and LPS outer core terminal residues losing SA was to be constructed. PCR and RT-PCR were used to confirm the mutant. Capability of CJ LPS binding to cholera toxin B subunit (CTB) was tested. Guinea pigs were systematically immunized with LPS of the wild and the mutant strains, respectively. Titers of anti-LPS and anti-ganglioside GM(1) IgG antibodies in sera of immunized guinea pigs were detected by ELISA. Pathological study for sciatic nerves of both Guinea pigs either immunized systematically or perineural injection with their immunized serum was finished.</p><p><b>RESULTS</b>(1) The mutant of CJ O:19 strain with inactivated neuB1 gene was successfully constructed and lost transcriptional activity of neuB1 gene in the mutant strain was confirmed by PCR and RT-PCR. SA was well demonstrated by both acidic ninhydrin reaction and periodate-resorcinol reaction in the LPS of wild strain but not in the mutant LPS; (2) Compared with the titers before immunization, the titers of anti-GM(1) IgG antibody increased in sera of guinea pigs immunized with LPS of the wild strain. However there were no detectable anti-GM(1) IgG antibody in sera of the animals immunized with mutant LPS and PBS. (3) The incidence of pathological fibers of sciatic nerves in wild CJ LPS group (17.3%) was significantly higher than the mutant CJ LPS group (chi(2) = 125, P < 0.01); the difference between the mutant CJ LPS group and control group was not statistically significant (chi(2) = 1.633, P > 0.05). (4) After perineural injection with immunized serum, the incidence of pathological fibers of sciatic nerves in wild strain group (67.8%) was also significantly higher than the incidence of mutant group (P < 0.01).</p><p><b>CONCLUSION</b>A mutant of CJ O:19 strain neuB1 gene inactivated and SA component of terminal structure of LPS lost was successfully constructed. And it no longer expressed SA component which is the normal terminal structure of LPS in wild strain. The capability of the wild strain to induce increased titers of anti-GM(1) antibody and immune-mediated nerve damage was simultaneously lost for the mutant strain. It could be a strong immunopathologic evidence to identify the molecular mimicry hypothesis between CJ LPS and ganglioside epitope in nerve on the pathogenesis of CJ related GBS. The terminal residues containing SA should be as the basic GM1-like structure in CJ LPS.</p>

Cloning of CTB-PROIN fusion gene and its expression in Escherichia coli / 生物工程学报

A fusion gene CTB-PROIN, in which Proinsulin gene was fused to the 3' end of CTB gene by a hinge peptide 'GPGP', was constructed and cloned into pET-30a(+) to obtain a prokaryotic expression vector pETCPI. Subsequently the recombinant plasmid pETCPI was transformed into E. coli stain BL21 (DE3). After induced by IPTG, the expression product was analyzed by sodium dodecyl sulphate-polyacrylamide gel (15%) electrophoresis (SDS-PAGE), and its result indicated that the recombinant protein CTB-PROIN was expressed and accumulated as inclusion bodies. The recombinant CTB-PROIN protein accumulated to the level of 25% of total bacterial proteins. After inclusion bodies was denaturalized and refolded in vitro, significant assembly of monomers had occurred, and the recombinant protein represented assembled pentamers. The results of western blotting analysis also demonstrated that the fusion protein could be recognized by the anti-CT and anti-insulin antibody, respectively. In addition, the result of the CTB-PROIN-GM1 binding assay, that the protein could bind to monosialoganglioside specifically, showed it possesed biological activity in vitro. These results provided the possibility of developing a cheaper and more efficient oral vaccine for type I diabetes using such constructs.

GM1 stabilizes expression of NMDA receptor subunit 1 in the ischemic hemisphere of MCAo/reperfusion rat / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

<p><b>OBJECTIVE</b>To determine the protective effect of monosialoganglionside (GM1) and evaluate the influence of GM1 on expression of N-methyl-D-aspartate receptor subunit 1 (NMDAR1) in Sprague-Dawley (SD) rats with focal cerebral ischemia-reperfusion (I/R).</p><p><b>METHODS</b>Left middle cerebral artery (MCA) was occluded by an intraluminal suture for 1 h and the brain was reperfused for 72 h in SD rats when infarct volume was measured, GM1 (10 mg/kg) was given ip (intraperitoneally) at 5 min (group A), 1 h (group B) and 2 h (group C) after MCA occlusion (MCAo). Expression of NMDAR1 was detected by Western blot at various time after reperfusion (4 h, 6 h, 24 h, 48 h and 72 h) in ischemic hemispheres of the rats with or without GM1 administered.</p><p><b>RESULTS</b>(1) Adjusted relative infarct volumes of groups A and B were significantly smaller than that of group C and the control group (P<0.01 and P<0.05, respectively). (2) Expression level of NMDAR1 was temporally high at 6 h after reperfusion, and dipped below the normal level at 72 h after reperfusion. GM1 at 5 min after MCAo significantly suppressed the expression of NMDAR1 at 6 h after reperfusion (P<0.05 vs the control). At 72 h after reperfusion, the NMDAR1 expression level of rats treated with GM1 administered (at 5 min or 2 h after MCAo) was significantly higher than that of the control (P<0.05).</p><p><b>CONCLUSION</b>GM1 can time-dependently reduce infarct volume in rats with focal cerebral I/R partly through stabilizing the expression of NMDAR1.</p>

The effects of GM1 and bFGF synergistically inducing adult rat bone marrow stromal cells to form neural progenitor cells and their differentiation / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the effects of GM1 on inducing adult rat bone marrow stromal cells (MSCs) to form neural progenitor cells and their differentiation.</p><p><b>METHODS</b>Purified MSCs were induced by different components of basic fibroblast growth factor (bFGF) alone, GM1 alone or combination of bFGF with GM1. After 3 days' incubation, fibronectin and collagen I were detected with immunocytochemistry, and nestin was detected with immunofluorescence. Neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP) and galactose cerebroside (GalC) were detected with immunocytochemistry after 7 days' incubation.</p><p><b>RESULTS</b>After induction with bFGF alone or combination of bFGF and GM1, some MSCs exhibited the phenotypes of neural progenitor cells, and then neurons and astrocytes. In these two groups, the positive cells for fibronectin and collagen I decreased markedly after 3 days' induction. At the same time, the positive cells for nestin increased markedly. After 7 days' induction, NSE and GFAP-positive cells increased significantly. Furthermore, the addition of bFGF and GM1 caused the maximal variation. However, addition of GM1 alone had no inductive effects.</p><p><b>CONCLUSIONS</b>Combination of bFGF with GM1 may synergistically promote the transformation of MSCs and differentiation into neurons and astrocyte-like cells. The results suggest a promising route for the application of MSCs.</p>

Titulação de anticorpos anti-gangliosídeos no soro de pacientes com lesão medular crônica e precedendo tratamento com gangliosídeo Gm1 / Titration of serum anti-ganglioside antibodies in patients with chronic medular injury previos to treatment with GM1 ganglioside

Soro de 150 pacientes com lesão medular completa com 6 a 12 meses de duração foi analisado para titulação de anticorpos anti-gangliosídeos pelo método ELISA (IgG monosialo GM1, IgM monosialo GM1, IgG asialo GM1, IgM asialo GM1, IgG disialo GD1b e IgM disialo GD1B). Somente 4 pacientes apresentaram títulos elevados de anticorpos contra asialo GM1 (IgM). Os demais apresentaram níveis de anticorpos abaixo dos valores de referência e foram todos tratados com GM1 na dose de 100 mg por dia i.m. Todos os pacientes foram acompanhados clinicamente durante e após o tratamento com GM1. Não foram observados efeitos adversos importante com a medicação. O tratamento de pacientes lesados medulares crônicos com o gangliosídeo GM1 mostrou-se seguro, nos pontos sem positividade sorológica para anticorpos anti-GM1.

Study on protective effect of monosialoganglioside (GM1) on injury induced by oxygen glucose deprivation/reperfusion in rat hippocampal slices / 中国应用生理学杂志

<p><b>AIM</b>To investigate the protective effect of monosialoganglioside (GM1) on injury induced by oxygen glucose deprivation/reperfusion (OGD/Rep) in rat hippocampal slices.</p><p><b>METHODS</b>The protective effects of GM1 on hippocampal slices after OGD/Rep were observed by detecting the light transmittance (LT) changes of rat hippocampal slices and 2, 3, 5-triphenyltetrazolium chloride (TTC) staining of rat hippocampal slices.</p><p><b>RESULTS</b>(1) In four groups treated with 0 (control), 0.1, 1.0, 10 micromol/L GM1, the peak of light transmittance (LT) in the slices treated with 1.0 micromol/L GM1 was significantly lower than that of the control and the group treated with 0.10 micromol/L GM1 (P < 0.01, ANOVA), while the peak of LT in the slices treated with 10.0 micromol/L GM1 was significantly lower than that of the other groups (P < 0.01, ANOVA). The time to reach the peak of LT in four groups was significantly different from each other (P < 0.05, Kruskal-Wallis test). The time to reach the peak of LT in the group treated with 1 micromol/L GM1 was the significantly longer than that in the control (P < 0.01, Mann-Whitney U test). (2) There was characteristic dose-response relationship between GM1 and TTC staining of rat hippocampal slices. In the five groups, treated with 0 (control), 0.01, 0.1, 1.0, 10 micromol/L GM1 respectively, TTC staining in the group treated with 1 micromol/L GM1 was the deepest (P < 0.05 vs. control, 0.01 and 0.1 micromol/L GM1 group, ANOVA), and the next was in the group treated with 10 micromol/L GM1 (P < 0.05 vs. control and 0.01 micromol/L GM1 group, ANOVA).</p><p><b>CONCLUSION</b>GM1 could protect injury induced by OGD/Rep in rat hippocampal slices effectively in vitro.</p>