To evaluate the protective effects of Ginkgo biloba extract (GBe) which has antioxidant activity against peripheral neuropathy due to diabetes mellitus, slow axonal transport and morphology of sciatic nerve including endoneurial microvessels were examined in 12 rats with diabetes mellitus induced by streptozotocin (STZ, 60mg/kg, b.w., i.p.). Six of the diabetic rats were treated with 0.1% of GBe for 6 weeks from one week after the STZ injection. Serum glucose and lipid peroxide levels in GBe−treated diabetic rats were significantly lower than those in untreated diabetic rats (p<0.01, respectively), though the serum glucose level was higher than that in the control rats. L−[35S] methionine pulse radiolabeling with subsequent gel fluorography demonstrated that mean velocities (Vmean) of actin and β−tubulin, i.e. slow component b(SCb) transport in untreated diabetic rats were significantly lower than those in control rats (p<0.05, respectively); mean diameter of axons in the former rats was significantly smaller than that in the latter (p<0.01). Vmean of actin transport in GBe−treated diabetic rats was significantly faster than that in untreated diabetic rats (p<0.05). Vmean of slow axonal transport was significantly correlated with mean diameter of axons in the three groups of rats combined (p<0.01). On electron microscopy, severe altered endoneurial microvessels decreasing in luminal area together with endothelial cell degeneration or hypertrophy, pericyte debris and basement membrane thickening were observed in untreated diabetic rats; on the other hand these findings were less prominent in the diabetic rats treated with GBe. It is suggested that GBe treatment may protect disturbed slow axonal transport and pathological alterations of peripheral nerve with abnormal endoneurial microvasculature from diabetes mellitus by antioxidant activity.
Rattus norvegicus ; lower case pea ; Streptozocin ; Science of Morphology ; slow axonal transport

Time-dependent translocational changes of Synapsin I (SyI), a synaptic vesicle-associated phosphoprotein and its involvement in the axonal transport were investigated in the regenerating axonal sprouts. A weak SyI immunoreactivity (IR) was found in the axoplasm of normal axons. Rat sciatic nerves were crush-injured by ligating with 1-0 silk thread at the mid-thigh level and released from the ligation 24 h later. At various times after release, immunocytochemistry was performed. SyI was translocated from the proximal to the distal site of ligation and also involved in the sprouting of regenerating axons. The distribution patterns of SyI IR were changed in the crush-injured nerves. SyI immunoreactive thin processes were strongly appeared in the proximal region from 1 h after release. After 3 h, a very strong IR was expressed. The intense SyI immunoreactive thin processes were elongated distally and were changed the distribution pattern by time-lapse. After 12 h, strong immunoreactive processes were extended to the ligation crush site. At 1 day, a very intense IR was expressed. At 2 days, immunoreactive thin processes extended into the distal region over the ligation crush site and strong IR was observed after 3 days. SyI was accumulated in the proximal region at the early phases after release. These results suggest that SyI may be related to the translocation of vesicles to the elongated membranes by a fast axonal transport in the regenerating sprouts.
Animals ; Axonal Transport ; Axons/*physiology/ultrastructure ; Immunohistochemistry ; Male ; Nerve Crush ; Nerve Regeneration/*physiology ; Protein Transport ; Rats ; Rats, Sprague-Dawley ; Sciatic Nerve/physiology ; Synapsins/*metabolism ; Time Factors

OBJECTIVETo study the expression of tau-related protein in spinal cord of Chinese patients with Alzheimer's disease.

METHODSGallays-Braak stain and immunohistochemical study for tau protein (AT8) were carried out in the spinal cord tissue (T2, T8, T10, L2 and S2 segments) of 3 Chinese patients with Alzheimer's disease. Seven age-matched cases without evidence of dementia or neurologic disease were used as controls.

RESULTSNeurofibrillary tangles were identified in the neurons of anterior horn in 2 Alzheimer's disease cases but none was observed in the controls. Tau-positive axons and astroglia were detected in all Alzheimer's disease cases. Tau immunoreactivity in spinal cord of the patients correlated with that in brain tissue.

CONCLUSIONThe expression of tau-related protein is demonstrated in the spinal cord of Alzheimer's disease patients suggesting that axonal transport defect may play a role in the pathogenesis of Alzheimer's disease.

Aged ; Alzheimer Disease ; metabolism ; pathology ; Axonal Transport ; Axons ; metabolism ; pathology ; Humans ; Male ; Neurofibrillary Tangles ; metabolism ; pathology ; Phosphorylation ; Spinal Cord ; metabolism ; pathology ; tau Proteins ; metabolism

Hereditary peripheral neuropathies can be categorized as hereditary motor and sensory neuropathies (HMSN), hereditary motor neuropathies (HMN), and hereditary sensory neuropathies (HSN). HMSN, HMN, and HSN are further subdivided into several subtypes. Here, we review the most recent findings in the molecular diagnosis and therapeutic strategy for hereditary peripheral neuropathies. The products of genes associated with hereditary peripheral neuropathy phenotypes are important for neuronal structure maintenance, axonal transport, nerve signal transduction, and functions related to the cellular integrity. Identifying the molecular basis of hereditary peripheral neuropathy and studying the relevant genes and their functions is important to understand the pathophysiological mechanisms of these neurodegenerative disorders, as well as the processes involved in the normal development and function of the peripheral nervous system. These advances and the better understanding of the pathogenesis of peripheral neuropathies represent a challenge for the diagnoses and managements of hereditary peripheral neuropathy patients in developing future supportive and curative therapies.
Axonal Transport ; Hereditary Sensory and Autonomic Neuropathies ; Hereditary Sensory and Motor Neuropathy ; Humans ; Neurodegenerative Diseases ; Neurons ; Peripheral Nervous System ; Peripheral Nervous System Diseases ; Phenotype ; Signal Transduction ; Wills

PURPOSE: To investigate the replication of HSV within cultured cell and axonal transport of HSV within the axon of the ciliary nerve following the injection of HSV into a cultured ciliary nerve. METHODS: The explant of the ciliary nerve was cultured with a medium containing nerve growth factor for 30 days when the suspension of HSV-1 (Kos strain) was introduced into the culture dish to co-culture with the ciliary nerve. The ciliary nerve was examined with transmission electron microscopy 30 days after culture and 6 days after co-culture with HSV. RESULTS: The ultrastructure of the explant of the ciliary nerve co-cultured with HSV showed that the viral capsid acquired a viral envelope and viral core, and a capsid and inclusion body within the nucleus. The enveloped virus was scattered within the vesicles of the cytoplasm. The virus-like particles were identified at the axonal fibers. CONCLUSIONS: The co-culture of the explant of the ciliary nerve and HSV showed the replicative process of the HSV within the cultured cell. The virus-like particles within the axon showed the evidence axonal transport of the virus under culture conditions.
Axonal Transport* ; Axons ; Capsid ; Cells, Cultured ; Coculture Techniques ; Cytoplasm ; Herpes Simplex* ; Herpesvirus 1, Human ; Inclusion Bodies ; Microscopy, Electron, Transmission ; Nerve Growth Factor ; Simplexvirus*

Alzhelmer's disease (AD) is the most common cause of dementia that arises on a neuropathological background of amyloid plaques containing betaamylold (Abeta) derived from amyloid precursor protein (APP) and tau-rich neurofibrillary tangles. To date, the cause and progression of familial or sporadic AD have not been fully elucidated. About 10% of all cases of AD occur as autosomal dominant inherited forms of early-onset AD, which are caused by mutations in the genes encoding APP, presenilin-1 and presenilin-2. Proteolytic processing of APP by beta-gamma-secretase and caspase generates Abetaand carboxyl-terminal fragments of APP (APP-CTFs), which have been implicated in the pathogenesis of AD. The presenilins function as one of the gamma-secretases. Abetawhich is the main component of the amyloid plaques found, is known to exert neurotoxicity by accumulating free radicals, disturbing calcium homeostasis, evoking inflammatory response and activating signaling pathways. The CTFs have been found in AD patients' brain and reported to exhibit much greater neurotoxicity than Abeta. Furthermore CTFs are known to impair calcium homeostasis and learning and memory, triggering a strong inflammatory reaction through MAPKs- and NF-kappaB-dependent astrocytosis and iNOS induction. Recently, it was reported that CTF translocated into the nucleus and in turn, affected transcription of genes including glycogen synthase kinase-3beta which results in the induction of tau-rich neurofibrillary tangles and subsequently cell death. One of the hallmarks of AD, neurofibrillary tangles (NFT), is formed by insoluble intracellular polymers of hyperphosphorylated tau that is believed to cause apoptosis by disrupting cytoskeletal and axonal transport. This review covers the processing of APP, toxic mechanisms of Abetaand CTFs of APP, presenilin and also tau in relation to the pathogenesis of AD.
Amyloid ; Apoptosis ; Axonal Transport ; Brain ; Calcium ; Cell Death ; Dementia* ; Free Radicals ; Gliosis ; Glycogen Synthase ; Homeostasis ; Learning ; Memory ; Neurofibrillary Tangles ; Plaque, Amyloid ; Polymers ; Presenilin-1 ; Presenilin-2 ; Presenilins

Diabetic neuropathy is an axonal degenerative disease characterized by progressive axonal atrophy and reduced axonal transport. We were interested in the potential neuroprotective effects of nerve growth factor against diabetic neuropathies. To this aim we studied the effect of nerve growth factor on satellite cells, which might play a trophic role toward the related neuron, of the dorsal root ganglion in the streptozotocin-induced diabetic rats by electron in microscope . Diabetes was induced in rats by the streptozotocin. And recombinant human NGF was administrated everyday for 10 consecutive weeks. The results obtained are as follows : 1.In the diabetic induced group, the satellite cells revealed irregular nuclei.The neuron-satellite cell interface was more irregular and plicated than that of control. Large vacuoles and dense bodies were observed and no defects were in the ribosomes and rough endoplasmic reticulum. In the vacuoles, medium electron dense, fiber -like materials were occasionally observed. 2. In the experimental group of diabetic rats treated with NGF for 10 weeks, nucleus was round and the neuron-satellite interface was more regular. Vacuoles and dense bodies were less seen than diabetic rats. In the cytoplasm, many microtubules were observed. In these studies, we considered that streptozotocin induces changes of the satellite cell structure and NGF might improve cellular changes of the satellite cell exposed with streptozotocin.
Animals ; Atrophy ; Axonal Transport ; Axons ; Cytoplasm ; Diabetic Neuropathies ; Endoplasmic Reticulum, Rough ; Ganglia* ; Ganglia, Spinal ; Humans ; Microtubules ; Nerve Growth Factor* ; Neurons ; Neuroprotective Agents ; Rats* ; Ribosomes ; Streptozocin ; Vacuoles

OBJECTIVETo study the changes in microtubule motor protein expression in the spinal cord and sciatic nerve of rats exposed to carbon disulfide, and to investigate the possible molecular mechanism of changes in axonal transport in carbon disulfide-induced peripheral neuropathy.

METHODSHealthy adult male Wistar rats were randomly divided into one control group and three experimental groups (10 rats per group). The rats in experimental groups were intoxicated by gavage of carbon disulfide at a dose of 200, 400, or 600 mg/kg 6 times a week for 6 consecutive weeks, while the rats in control group were given the same volume of corn oil by gavage. Animals were sacrificed after exposure, with nerve tissue separated. The levels of dynein, dynactin, and kinesin in the spinal cord and sciatic nerve were determined by Western blot.

RESULTSThe content of dynein, dynactin, and kinesin in the sciatic nerve decreased significantly under exposure to carbon disulfide. The levels of dynein in the sciatic nerve were reduced by 23.47% and 33.34% at exposure doses of 400 and 600 mg/kg, respectively. The levels of dynactin in the sciatic nerve of the three experimental groups were reduced by 19.91%, 24.23%, and 41.30%, respectively. The level of kinesin was reduced by 25.98%under exposure to 600 mg/kg carbon disulfide. All the differences were statistically significant (P < 0.01). As compared with the control group, the 600 mg/kg group experienced a 28.24% decrease in level of dynactin in the spinal cord (P < 0.01), but no significant change was observed in the level of dynein or kinesin.

CONCLUSIONCarbon disulfide has an impact on microtubule motor protein expression in nerve tissues, which might be involved in the development of carbon disulfide-induced peripheral neuropathy.

Animals ; Axonal Transport ; drug effects ; physiology ; Carbon Disulfide ; toxicity ; Dynactin Complex ; Male ; Microtubule-Associated Proteins ; metabolism ; Nerve Tissue ; metabolism ; Peripheral Nervous System Diseases ; chemically induced ; metabolism ; Rats, Wistar ; Sciatic Nerve ; metabolism ; Spinal Cord ; metabolism

PURPOSE: This study was performed to investigate the ultrastructural changes of the optic nerve after intravitreal injection of herpes simplex virus-1. METHODS: Herpes simplex virus was separated from the culture media after observing the cytopathic effect on cultured vero cells. Viruses were then injected on the optic nerve head of 21 rabbit eyes. Eyes were enucleated at 1, 2, 3, 5, 7, 10, and 14 days after injection of herpes simplex virus and examined under the electron microscope. RESULTS: The intranuclear inclusion body was noted in eyes examined at 2 days after injection. The histopathological changes were perivascular infiltration of inflammatory cells, cytoskeletal degeneration of large diameter of myelinated nerve, demyelination of axonal nerve fiber, and the accumulation of mitochondria within axonal nerve fiber. CONCLUSIONS: These results suggest that optic neuritis may be induced by herpes simplex virus. The accumulation of mitochondria may be related to the interruption of the axonal transport through the axonal nerve fibers of optic nerve.
Axonal Transport ; Axons ; Culture Media ; Demyelinating Diseases ; Herpes Simplex* ; Intranuclear Inclusion Bodies ; Intravitreal Injections ; Mitochondria ; Myelin Sheath ; Nerve Fibers ; Optic Disk ; Optic Nerve ; Optic Neuritis* ; Rabbits* ; Simplexvirus ; Vero Cells

Glaucoma is characterized by loss of retinal ganglion cells (RGCs) and their axons. Retrograde axoplasmic transport blockade and excitotoxicity were proposed to be a major cause of RGC apoptosis. We conducted this study to characterize the episcleral vessel cauterization glaucoma model in the rat with respect to decreased retrograde axoplasmic flow and subsequent apoptotic RGC death. After episcleral vessels were cauterized in Sprague-Dawley rats, Fluorogold was injected into their superior colliculi by stereotactic method. Retrograde axoplasmic flow and TUNEL-stained apoptotic dead cells were observed microscopically. Elevated intraocular pressure was maintained for up to 6 weeks during follow-up. Retrograde axoplasmic flow to the rat retina was significantly decreased. Apoptotic RGC was selectively TUNELstained in the retina, especially at the ganglion cell layers. We concluded that elevated intraocular pressure caused apoptotic RGC death through retrograde axoplasmic flow blockage. Further studies will elucidate the neuroprotection strategies in glaucoma patients.
Animals ; *Apoptosis ; Axonal Transport ; Disease Models, Animal ; In Situ Nick-End Labeling ; *Intraocular Pressure ; Male ; Ocular Hypertension/*complications ; Rats ; Rats, Sprague-Dawley ; Retinal Ganglion Cells/*pathology ; Retrograde Degeneration/etiology ; Sclera/blood supply