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The immune modulator Linomide prevents neuronal death in injured peripheral nerves of the mouse

Neuronal death after injury or disease could result from imbalanced cytokine expression. Linomide (LS-2616, quinoline-3-carboxamide), a synthetic immunomodulator with effects on cytokine production, suppresses autoimmune diseases of the nervous system. Here adult mice were pre-treated with 200 mg/kg/day of Linomide for 9 days, after which the sciatic nerves were crushed. After another 10 days of L

Regenerating peripheral nerves release a diffusable protein kinase

Using [γ32P]ATP and 1-dimensional electrophoresis this report shows that a protein kinase is released in the culture medium from adult frog sciatic nerves during regeneration in vitro. The kinase, which phosphorylated serine and to some extent threonine residues, was released from non-neuronal cells. It showed an increased activity during the 3rd to 6th day after injury, coinciding with the injury

Protein kinase C inhibition has only a transient growth arresting effect on in vitro regenerating mouse sensory neurons

Adult mice sensory ganglia were cultured in an extracellular matrix gel. Analyses of extending axons were made 48 h (long-term) or immediately (short-term) after addition of protein kinase inhibitors. Long- and short-term growth was insensitive to protein kinase A/G inhibition by HA-1004. Long-term protein kinase C inhibition by chelerythrine affected only certain, long axons. In the short-term vi

Axonal outgrowth from adult mouse nodose ganglia In vitro is stimulated by neurotrophin-4 in a Trk receptor and mitogen-activated protein kinase-dependent way

The actions of neurotrophic factors on sensory neurons of the adult nodose ganglion were studied in vitro. The ganglia were explanted in an extracellular matrix-based gel that permitted observation of the growing axons. Neurotrophin-4 (NT-4) was a very efficient stimulator of outgrowth of axons from the nodose ganglion and had almost doubled the outgrowth length when this was analyzed after 2 days

Mitogen activated protein (MAP) kinase activity is increased in adult mouse superior cervical ganglia during culturing

We have used adult mouse superior cervical ganglia (SCG) to study the role of mitogen activated protein (MAP) kinase activity during axonal outgrowth in vitro. An initial peak in activity within the first hours of culture was followed by a substantially higher activity after 1 to 2 days, a time when axons were actively growing. The latter peak is probably a result of both higher levels of protein

Neurones and glial cells of the mouse sciatic nerve undergo apoptosis after injury in Vivo and in Vitro

Analogous to the death of developing neurones deprived of trophic factors, nerve injury in adult life could lead to nerve cell death by apoptosis. Here the occurrence of apoptotic mouse sciatic sensory neurones after injury was investigated by nick-labelling DNA breaks. A small proportion of the neurones reliably became apoptotic after injury in vivo. The response was strongly amplified when the n

Increased cyclic AMP in in vitro regenerating frog sciatic nerves inhibits Schwann cell proliferation bur has no effect on axonal outgrowth

In the present study the role of cAMP for axonal outgrowth and Schwann cell proliferation was studying using the cultured frog sciatic nerve. An intrinsic rise in nerve injury, both in vitro and in vivo. Treatment with 0.1‐1.0μM forskolin, an activator of the cAMP‐generating enzyme adenylyl cyclase, increased the cAMP content up to 13‐fold, but was yet without effect on axonal outgrowth during an

Retrograde axonal transport of locally synthesized proteins, e.g., actin and heat shock protein 70, in regenerating adult frog sciatic sensory axons

The local synthesis and subsequent retrograde axonal transport of [35S]methionine‐labelled proteins was studied in the in vitro regenerating adult frog sciatic sensory axons. By the use of a three compartment culture system, proteins in the outgrowth region were selectively labelled. After 2 days in culture a rise in TCA‐insoluble radioactivity was detected in the dorsal root ganglia, which could

Okadaic Acid and Cultured Frog Sciatic Nerves : Potent Inhibition of Axonal Regeneration in Spite of Unaffected Schwann Cell Proliferation and Ganglionic Protein Synthesis

Abstract: Okadaic acid (OA) is a frequently used phosphatase inhibitor that by inhibiting dephosphorylation increases the net phosphorylation level in various systems. In the present study OA was used to assess the role of balanced phosphorylation‐dephosphorylation reactions for successful regeneration of peripheral nerves. To achieve this, the effects of OA on phosphorylation levels, neurite outg

Increased levels of mitogen activated protein kinase (MAP-K) detected in the injured adult mouse sciatic nerve

Adult mouse sciatic nerves (SNs) with attached dorsal root ganglia (DRG) were analysed for the presence of mitogen activated protein kinase (MAP-K) during normal and regenerative conditions. By immunohistochemistry, MAP-k was found to be present in the normal nerve at low levels in both Schwann cells and DRG nerve cell bodies, with a profoundly increased expression during regeneration. In axonal o

Long-term adverse effects after curative radiotherapy and radical prostatectomy : population-based nationwide register study

Objective: The aim of this study was to assess the risk of serious adverse effects after radiotherapy (RT) with curative intention and radical prostatectomy (RP). Materials and methods: Men who were diagnosed with prostate cancer between 1997 and 2012 and underwent curative treatment were selected from the Prostate Cancer data Base Sweden. For each included man, five prostate cancer-free controls,

Upregulation of cytosolic phospholipase A2 correlates with apoptosis in mouse superior cervical and dorsal root ganglia neurons

The involvement of cytosolic phospholipase A2 (cPLA2) in apoptosis of adult mouse superior cervical and dorsal root ganglia neurons has been investigated by the use of immunohistochemistry for cPLA2 and DNA nick-end labeling for apoptotic cells, respectively, cPLA2 immunoreactivity was strongly upregulated in neurons of both preparations during in vitro culturing. By double labeling it was unequiv

Calmodulin and In Vitro Regenerating Frog Sciatic Nerves : Release and Extracellular Effects

Although calmodulin (CaM) is commonly considered to be an intracellular protein, it has been suggested lately that it is released and exerts functions extracellularly. In the present investigation this was studied in in vitro regenerating adult frog (Rana temporaria) sciatic nerves. Using a multi‐compartment incubation chamber, the non‐neuronal cells in the outgrowth region of such nerves were rad

Mitogen activated protein kinase inhibition by PD98059 blocks nerve growth factor stimulated axonal outgrowth from adult mouse dorsal root ganglia in vitro

Nerve growth factor stimulated axonal outgrowth from explanted mouse dorsal root ganglia is dependent on mitogen activated protein kinase. PD98059 ([2-(2'amino-3'-methoxyphenyl)-oxanaphthalen-4-one]) blocks mitogen activated protein kinase by inhibiting its immediate upstream activator, mitogen activated protein kinase kinase (also known as MEK). Here we used PD98059 to study the role of mitogen a

Regenerating Peripheral Axons Transport and Release Low‐Molecular‐Mass Materials In Vitro

Abstract: The release of radiolabeled material from regenerating frog sciatic nerves was studied using a multicom‐ partment chamber, in which the ganglia and the outgrowth region, respectively, were separated from the rest of the nerve. The nerves were incubated with radioactive amino acids in the ganglionic compartment, and the material transported to and released at the outgrowth region was coll

Phospholipase A2 activity is required for regeneration of sensory axons in cultured adult sciatic nerves

The adult frog dorsal root ganglia (DRGs) and their sciatic nerves (ScN) survive in organ culture for several days. About 3 days after a local test crush, the sensory axons start to regenerate into the distal nerve stump at a rate of approximately 0.6-0.9 mm/day. The axonal outgrowth is inhibited in a non-toxic way by low concentrations of three different phospholipase A2 (PLA2) inhibitors: 4-brom

Axonal outgrowth and neuronal apoptosis in cultured adult mouse dorsal root ganglion preparations : Effects of neurotrophins, of inhibition of neurotrophin actions and of prior axotomy

Dorsal root ganglia (L4 and L5) with attached spinal roots and nerve stumps were isolated from young adult mice and cultured in a layer of extracellular matrix material (matrigel). Within one day, a large number of axons grew out from the cut ends of the nerve and the dorsal root. The average outgrowth length was more than doubled by nerve growth factor, which also strongly increased the number of

Moderate elevation of extracellular potassium transiently inhibits regeneration of sensory axons in cultured adult sciatic nerves

The adult frog dorsal root ganglia (DRG) together with the sciatic nerve (ScN) has previously been shown to survive in organ culture for several days. If a local test crush is made at the beginning of culturing, there is an initial delay of about 3 days before the sensory axons start to grow into the distal nerve stump at a rate of about 0.6-0.9 mm/day. The present results showed that axonal growt

Early regeneration in vitro of adult mouse sciatic axons is dependent on local protein synthesis but may not involve neurotrophins

The sensory axons of the adult mouse sciatic nerve were shown to regenerate after a local test crush lesion in vitro in a serum-free medium. The average outgrowth distance of the leading axons after culturing for 3 days was 2.8 ± 0.1 mm, which was shorter than in vivo (3.8 ± 0.2 mm). With the use of a compartmentalised culture system we could show that regeneration was partially dependent on local

Protein kinase C and mouse sciatic nerve regeneration

We have studied the role of protein kinase C (PKC) in peripheral nerve regeneration by using the cultured adult mouse sciatic nerve, which displays regrowth of sensory axons under serum-free conditions. By the use of immunohistochemistry we show that one of the isoforms of PKC, PKCβ, is present in the nerve cell bodies of normal nerves and is upregulated after injury. In spite of this, the specifi