Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive lethal malignancy, characterized by late diagnosis, aggressive growth, and therapy resistance, leading to a poor overall prognosis. Emerging evidence shows that the peripheral nerve is an important non-tumor component in the tumor microenvironment that regulates tumor growth and immune escape. The crosstalk between the neuronal system and PDAC has become a hot research topic that may provide novel mechanisms underlying tumor progression and further uncover promising therapeutic targets. In this review, we highlight the mechanisms of perineural invasion and the role of various types of tumor innervation in the progression of PDAC, summarize the potential signaling pathways modulating the neuronal-cancer interaction, and discuss the current and future therapeutic possibilities for this condition.
Humans ; Carcinoma, Pancreatic Ductal/pathology* ; Pancreatic Neoplasms/therapy* ; Signal Transduction ; Peripheral Nerves/metabolism* ; Tumor Microenvironment

OBJECTIVETo study the ability of aqueous extract of Hericium erinaceus mushroom in the treatment of nerve injury following peroneal nerve crush in Sprague-Dawley rats.

METHODSAqueous extract of Hericium erinaceus was given by daily oral administration following peroneal nerve crush injury in Sprague-Dawley rats. The expression of protein kinase B (Akt) and mitogen-activated protein kinase (MAPK) signaling pathways; and c-Jun and c-Fos genes were studied in dorsal root ganglia (DRG) whereas the activity of protein synthesis was assessed in peroneal nerves by immunohistochemical method.

RESULTSPeripheral nerve injury leads to changes at the axonal site of injury and remotely located DRG containing cell bodies of sensory afferent neurons. Immunofluorescence studies showed that DRG neurons ipsilateral to the crush injury in rats of treated groups expressed higher immunoreactivities for Akt, MAPK, c-Jun and c-Fos as compared with negative control group (P <0.05). The intensity of nuclear ribonucleoprotein in the distal segments of crushed nerves of treated groups was significantly higher than in the negative control group (P <0.05).

CONCLUSIONH. erinaceus is capable of promoting peripheral nerve regeneration after injury. Potential signaling pathways include Akt, MAPK, c-Jun, and c-Fos, and protein synthesis have been shown to be involved in its action.

Agaricales ; chemistry ; Animals ; Axons ; pathology ; Female ; Ganglia, Spinal ; metabolism ; Glucans ; analysis ; MAP Kinase Signaling System ; Nerve Crush ; Nerve Regeneration ; physiology ; Peripheral Nerves ; enzymology ; physiology ; Peroneal Nerve ; physiology ; Protein Biosynthesis ; Proto-Oncogene Proteins c-akt ; metabolism ; Proto-Oncogene Proteins c-fos ; genetics ; metabolism ; Proto-Oncogene Proteins c-jun ; genetics ; metabolism ; Rats, Sprague-Dawley

OBJECTIVETo investigate whether cannabinoid receptor 1 (CB1R) is involved in nerve growth in endometriosis-associated ectopic cyst.

METHODSThe effect of CB1R agonist and antagonist on the expression of pan-neuronal marker protein gene product (PGP) 9.5 in ectopic cyst was examined by immunofluorescence and Western blot in endometriosis model of 18 rats.

RESULTSImmunofluorescence revealed that PGP 9.5 was expressed in the nerve fibers and was mainly distributed in the cyst hilum. Western blot revealed that the protein density of either PGP 9.5 (2 week: 0.38 ± 0.05; 4 week: 0.63 ± 0.03; 8 week: 0.80 ± 0.07, P < 0.01) or CB1R (2 week: 0.48 ± 0.04; 4 week: 0.68 ± 0.01; 8 week: 0.80 ± 0.03, P < 0.01) in the ectopic cyst increased with cyst size. In addition, compared to control group (0.75 ± 0.01), PGP 9.5 expression in the ectopic cyst was promoted by CB1R agonist ACPA (0.81 ± 0.01, P < 0.05), and inhibited by CB1R antagonist AM251 (0.67 ± 0.03, P < 0.01).

CONCLUSIONSCB1R was involved in the nerve growth of ectopic cyst associated with endometriosis.

Animals ; Blotting, Western ; Cysts ; metabolism ; Disease Models, Animal ; Endometriosis ; metabolism ; Female ; Peripheral Nerves ; growth & development ; metabolism ; Piperidines ; pharmacology ; Pyrazoles ; pharmacology ; Rats ; Receptor, Cannabinoid, CB1 ; antagonists & inhibitors ; physiology ; Ubiquitin Thiolesterase ; metabolism

BACKGROUND/AIMS: Vitis vinifera grape seed extract (VVE) contains oligomeric proanthocyanidins that show antioxidant and free radical-scavenging activities. We evaluated VVE for its neuroprotective effect in prediabetic mice induce by a high-fat diet (HD). METHODS: Mice were divided into four groups according to VVE dose: those fed a normal diet (ND; n = 10), HD (n = 10), HD with 100 mg/kg VVE (n = 10), and HD with 250 mg/kg VVE (n = 10). After 12 weeks, immunohistochemical analyses were carried out using a polyclonal antibody against antiprotein gene product 9.5 (protein-gene-product, 9.5), and intraepidermal innervation was subsequently quantified as nerve fiber abundance per unit length of epidermis (intraepidermal nerve fiber, IENF/mm). RESULTS: Daily administration of VVE at doses of 100 or 250 mg/kg for 12 weeks protected HD mice from nerve fiber loss compared to untreated mice, as follows (IENF/mm): controls (40.95 +/- 5.40), HD (28.70 +/- 6.37), HD with 100 mg/kg (41.14 +/- 1.12), and HD with 250 mg/kg (48.98 +/- 7.01; p < 0.05, HD with VVE vs. HD). CONCLUSIONS: This study provides scientific support for the therapeutic potential of VVE in peripheral neuropathy in an HD mouse model. Our results suggest that VVE could play a role in the management of peripheral neuropathy, similar to other antioxidants known to be beneficial for diabetic peripheral neuropathy.
Animals ; Antioxidants/*pharmacology ; Biological Markers/blood ; Blood Glucose/drug effects/metabolism ; Body Weight/drug effects ; Diabetic Neuropathies/blood/etiology/pathology/*prevention & control ; *Diet, High-Fat ; Disease Models, Animal ; Dose-Response Relationship, Drug ; Epidermis/*innervation ; Grape Seed Extract/*pharmacology ; Lipids/blood ; Male ; Mice ; Mice, Inbred C57BL ; Neuroprotective Agents/*pharmacology ; Peripheral Nerves/*drug effects/pathology ; Phytotherapy ; Plants, Medicinal ; Prediabetic State/blood/*drug therapy/etiology ; Time Factors ; *Vitis

OBJECTIVETo study the role of CYP2E1 in the protective effects and mechanism of garlic oil (GO) on the peripheral nerve injuries induced by n-hexane.

METHODSFifty male Wistar rats were randomly divided into five groups (n = 10): the control, the GO (80 mg/kg) control, the n-hexane (2000 mg/kg) model, the low dose GO (40 mg/kg) plus n-hexane, and the high dose GO (80 mg/kg) plus n-hexane groups. All rats were treated by intragastric administration 6 times a week for 10 weeks. The gait scores were determined every two weeks for monitoring the peripheral neurotrosis. All rats were sacrificed in 10 weeks, the activities and expression levels of hepatic CYP2E1 and 2, 5-HD in serum were examined.

RESULTSAs compared with control group, the content and activity of hepatic CYP2E1 in GO control group reduced by 83.1% and 48.3% respectively (P < 0.01), the content and activity of hepatic CYP2E1 in model group increased by 112.5% and 72.2% respectively (P < 0.01). As compared with model group, the contents of hepatic CYP2E1 in low dose and high dose GO groups reduced by 32.9% and 39.1% respectively, the activities of hepatic CYP2E1 in low dose and high dose GO groups reduced by 27.4% and 44.5% respectively (P < 0.01); the contents of serum 2,5-HD in low dose and high dose GO groups reduced by 47.7% and 78.7% respectively (P < 0.01). The gait scores in model, low dose and high dose GO groups were significantly lower than that in control group, but the gait scores in low dose and high dose GO groups were significantly lower than that in model group (P < 0.05).

CONCLUSIONGarlic oil can effectively reduce the peripheral neurotrosis induced by n-hexane due to the decreased content and activity of hepatic CYP2E1, resulting in the reduced formation of 2, 5-HD from n-hexane.

Animals ; Cytochrome P-450 CYP2E1 ; metabolism ; Garlic ; Hexanes ; toxicity ; Liver ; drug effects ; enzymology ; Male ; Peripheral Nerves ; drug effects ; pathology ; Plant Oils ; pharmacology ; Rats ; Rats, Wistar

The aim of this study was to investigate the effect of platelet-rich plasma (PRP) on cavernous nerve (CN) regeneration and functional status in a nerve-crush rat model. Twenty-four Sprague-Dawley male rats were randomly divided into three equal groups: eight had a sham operation, eight underwent bilateral nerve crushing with no further intervention and eight underwent bilateral nerve crushing with an immediate application of PRP on the site of injury. Erectile function was assessed by CN electrostimulation at 3 months and nerve regeneration was assessed by toluidine blue staining of CN and nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase staining of penile tissue. Three months after surgery, in the group that underwent bilateral nerve crushing with no further intervention, the functional evaluation showed a lower mean maximal intracavernous pressure (ICP) and maximal ICP per mean arterial pressure (MAP) with CN stimulation than those in the sham group. In the group with an immediate application of PRP, the mean maximal ICP and maximal ICP/MAP were significantly higher than those in the injured control group. Histologically, the group with the application of PRP had more myelinated axons of CNs and more NADPH-diaphorase-positive nerve fibres than the injured control group but fewer than the sham group. These results show that the application of PRP to the site of CN-crush injury facilitates nerve regeneration and recovery of erectile function. Our research indicates that clinical application of PRP has potential repairing effect on CN and peripheral nerves.
Animals ; Disease Models, Animal ; Electric Stimulation ; Erectile Dysfunction ; pathology ; physiopathology ; therapy ; Male ; NADPH Dehydrogenase ; metabolism ; Nerve Regeneration ; physiology ; Penile Erection ; physiology ; Penis ; innervation ; Peripheral Nerve Injuries ; Peripheral Nerves ; metabolism ; pathology ; Platelet Transfusion ; Platelet-Rich Plasma ; Radiculopathy ; etiology ; pathology ; physiopathology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo evaluate the different effect on the expression of Calcitonin gene related peptide (CGRP)and neuropeptide Y (NPY) between tissue engineered bone with vascular bundle graft in vivo and that with sensory nerve tract graft in vivo.

METHODThirty-six healthy New Zealand rabbits were divided into 3 groups randomly and equally: vascular bundle group (A), sensory nerve tract group (B), tissue-engineering group (C). Group A segmental bone defect of 1.5 cm long was made at the right femur in each animal. After plate fixation, the defects were implanted respectively with the engineered bone prepared in the above-mentioned 3 methods. At 3, 6 and 12 months post-operatively, the distribution of CGRP and NPY in the new bone were detected by immunohistochemistry and analyzed semi-quantitatively by image analysis software.

RESULTSCGRP and NPY immuno-histochemical results indicated their contents increased significantly in all 3 groups as time passed (P = 0.000). Compared with group B, the contents of CGRP and NPY in group A significantly increased at 3 months (P = 0.000), but there was no statistic difference between them at 6 or 12 months (P > 0.05). The expression of CGRP and NPY in both group A and B were significantly more than that in group C at 3, 6 or 12 months (P = 0.000).

CONCLUSIONImplantation of vascular bundle into tissue-engineered bone can significantly improve the CGRP and NPY contents at early 3 months comparing with Implantation of sensory tract into tissue-engineered bone, but the changes are not significant at 6 or 12 months post-operatively.

Animals ; Blood Vessels ; transplantation ; Bone Substitutes ; Calcitonin Gene-Related Peptide ; metabolism ; Disease Models, Animal ; Femur ; injuries ; Male ; Neuropeptide Y ; metabolism ; Peripheral Nerves ; transplantation ; Rabbits ; Random Allocation ; Tissue Engineering

OBJECTIVETo investigate the association of nerve growth factor (NGF) expression with perineural invasion and pain in pancreatic cancer.

METHODSNGF expression was detected by Northern blotting and immunohistochemistry in 28 pancreatic cancer and 20 normal pancreatic tissue samples. Correlation analysis of the results with the extent of perineural invasion, pain and histopathologic characteristics of the tumor was performed.

RESULTSNorthern blot analysis revealed that NGF levels in pancreatic cancer tissues increased by 3.1 folds in comparison with normal pancreas tissue (P<0.05), and immunohistochemistry detected the presence of obvious NGF expression in the cytoplasm of pancreatic cancer cells. Tumors with high NGF expression were associated with more frequent perineural invasion (P<0.01), and increased NGF expression was related to more intense pain (P<0.01).

CONCLUSIONIncreased NGF expression may contribute to perineural invasion and pain in pancreatic cancer.

Adult ; Aged ; Blotting, Northern ; Carcinoma, Pancreatic Ductal ; genetics ; metabolism ; pathology ; Female ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Neoplasm Invasiveness ; Nerve Growth Factor ; biosynthesis ; genetics ; Neuralgia ; genetics ; metabolism ; pathology ; Pancreatic Neoplasms ; genetics ; metabolism ; pathology ; Peripheral Nerves ; metabolism ; pathology ; RNA, Messenger ; biosynthesis ; genetics

Diseases of the peripheral nervous system are the most prevalent in patients with end-stage renal disease (ESRD). Although increased blood levels of lead in ESRD have been reported, the role of lead remains to be elucidated. The purpose of this study was to determine the connection of blood lead concentration with peripheral nerve conduction velocity. One hundred ninety-eight healthy subjects (control group) and 68 patients with ESRD undergoing hemodialysis (ESRD group) were enrolled. Nerve conduction was measured within two hours after hemodialysis. Orthodromic sensory nerve action potentials and compound muscle action potentials were recorded on the median, ulnar, and radial nerves. Hemoglobin-corrected blood lead was significantly higher in ESRD patients than in controls (9.1+/-2.8 microgram/dL vs. 5.9+/-2.3 microgram/dL, p<0.001). 32.4% of 68 ESRD patients with diabetes mellitus were significantly related to poorer motor and sensory nerve conduction velocity (p<0.001). However, blood lead was not a significant predictor of the nerve conduction velocity (p>0.05). Our result suggested that even though the blood lead levels were high in ESRD, they were not associated with the decline of peripheral nerve function. Diabetes mellitus is a primary independent risk of neuropathy in ESRD patients.
Peripheral Nervous System Diseases/blood/etiology/physiopathology ; Peripheral Nerves/physiopathology ; Neural Conduction/*physiology ; Middle Aged ; Male ; Lead/*blood/metabolism ; Kidney Failure, Chronic/*blood/complications/*physiopathology ; Humans ; Female ; Diabetic Neuropathies/blood/physiopathology ; Case-Control Studies ; Bone and Bones/metabolism ; Body Burden ; Adult

OBJECTIVETo explore the pathogenesis of the damage to peripheral nerves induced by Campylobacter jejuni exotoxin (CJT).

METHODS(1) Animal models: (1) The CJT was extracted from PEN 19-CJ and injected perineurally and intravenously to Wistar rats. (2) The sera and the supernatants of peripheral blood mononuclear cells (PBMCs), taken from the rats immunized with the CJT, were injected perineurally at sciatic nerves of experimental rats and intravenously, respectively. (2) Histopathologic study of sciatic nerves: the animals were sacrificed and their sciatic nerves were examined for tease fibers, transverse section with toluidine blues staining and electron microscopy. (3) Immunohistochemistry: sections of sciatic nerves of either normal rats or human which were incubated with CJT and the sciatic nerves with pathological changes induced by CJT were obtained for observation of the binding capability of CJT with peripheral nerves by SABC and FITC-immunofluorescence methods, and nucleic acid hybridization techniques for detection of TNF-alpha mRNA expression in pathological sciatic nerves samples.

RESULTS(1) Remarkable peripheral neuropathies with axon degeneration and/or demyelination were found in the nerves induced by both CJT injection perineurally and intravenously. The axon degeneration was more obvious. Pathological changes were identified in 76.8% (2,763/3,600) of teasing fibers after perineural injection, but only 9.6% (230/2,400) of fibers were damaged in control group (P < 0.01). The peak severity of fiber damage was found on the 3rd day after CJT intravenous injection with the incidence of abnormal fibers was 19.5% (390/2,000), and abnormalities of 15.5% (310/2000) on the 14th day. However, no abnormal changes were demonstrated in control group (P < 0.01). So was in the groups injected with anti-CJT sera and the supernatants of PBMCs compared with control (P > 0.05). (2) Binding of CJT to the nerve was found dominant in the sciatic nerves taken from normal rats or human either incubated with CJT or in the pathological sciatic nerves induced by CJT to various degrees. The binding of CJT to all these nerves was determined. (3) After intravenous injection with CJT, no histopathologic change could be found in the other viscera of the rats, with the exception of remarkable pathological change in peripheral nerves.

CONCLUSIONS(1) CJT could remarkably damage the peripheral nerves in rats. Specific pathogenicity of CJT to peripheral nerves was well shown, because no histopathologic abnormalities could be found in the other viscera, such as brain, liver and kidney etc. although there was remarkable pathological change along the peripheral nerve in the animals. (2) No immunological pathogenicity of CJT could be demonstrated in the nerves of rats after immunization with CJT.

Animals ; Antibodies, Anti-Idiotypic ; blood ; Bacterial Toxins ; immunology ; toxicity ; Campylobacter jejuni ; immunology ; Exotoxins ; immunology ; toxicity ; Gene Expression ; drug effects ; Peripheral Nerves ; drug effects ; metabolism ; pathology ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Wistar ; Sciatic Nerve ; drug effects ; metabolism ; pathology ; Tumor Necrosis Factor-alpha ; genetics