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Jung Jae Park, Hong Joo Moon, Jin Hyun Park, Taek Hyun Kwon, Youn-Kwan Park and Joo Han Kim

OBJECT

To determine the role played by mitogen-activated protein kinase (MAPK) signaling in the interactions between macrophages and intervertebral disc (IVD) cells, it was hypothesized that MAPK inhibition would modulate the production of the proinflammatory cytokines associated with inflammatory reaction in IVD cells.

METHODS

Human annulus fibrosus (AF) and nucleus pulposus (NP) cells were cocultured with phorbol myristate acetate-stimulated macrophage-like THP-1 cells, with and without SB202190 (a p38-α and -β inhibitor), SP600125 (a c-Jun N-terminal kinase [JNK] inhibitor), and PD98059 (an extracellular signal-regulated kinase [ERK] 1/2 inhibitor). The cytokines in conditioned media from cocultured and macrophage-exposed (nemotic) cells were assayed using enzyme-linked immunosorbent assays (ELISAs).

RESULTS

Interleukin (IL)-6 and IL-8 were secreted in greater quantities by the cocultured cells compared with naive IVD cells and macrophages (MΦ) cultured alone. The tumor necrosis factor (TNF)- α and IL-6 levels produced by the NP cells cocultured with MΦs (NP-MΦ) were significantly lower than those produced by AF cells cocultured with MΦs (AF-MΦ). SB202190 dose-dependently suppressed IL-6 secretion by AF-MΦ and NP-MΦ cocultures, and 10 μM SB202190 significantly decreased IL-6 and IL-8 production in nemotic AF and NP pellets. SP600125 at 10 μM significantly suppressed the production of TNF α IL-6. and IL-8 in AF-MΦ and NP-MΦ cocultures and significantly suppressed IL-1β production in the NP-MΦ coculture. Administration of 10 μM PD98059 significantly decreased IL-6 levels in the AF-MΦ coculture, and decreased the levels of TNF α and IL-8 in both the AF-MΦ and NP-MΦ cocultures.

CONCLUSIONS

The present study shows that inhibitors of p38 MAPK effectively controlled IL-6 production during inflammatory reactions and that JNK and ERK1/2 inhibitors successfully suppressed the production of major proinflammatory cytokines during interactions between macrophages and IVD cells. Therefore, selective blockade of these signals may serve as a therapeutic approach to symptomatic IVD degeneration.

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Bum-Joon Kim, Junseok W. Hur, Jong Soo Park, Joo Han Kim, Taek-Hyun Kwon, Youn-Kwan Park and Hong Joo Moon

OBJECT

An in vitro study was performed to understand the potential roles of matrix metalloproteinase (MMP)-2 and MMP-9 in the elastin degradation of human ligamentum flavum (LF) cells via treatment with tumor necrosis factor-α (TNFα) and interleukin-1β (IL-1β). Previous studies have identified a decreased elastin to collagen ratio in hypertrophic LF. Among the extracellular matrix remodeling endopeptidases, MMP-2 and MMP-9 are known to have elastolytic activity. The hypothesis that activated LF cells exposed to inflammation would secrete MMP-2 and MMP-9, thereby resulting in elastin degradation, was examined.

METHODS

To examine MMP-2 and MMP-9 expression in human LF, cells were isolated and cultured from LF tissues that were obtained during lumbar disc surgery. Isolated LF cells were equally divided into 3 flasks and subcultured. Upon cellular confluency, the LF cells were treated with TNFα, IL-1β, or none (as a control) and incubated for 48 hours. The conditioned media were collected and assayed for MMP-2 and MMP-9 using gelatin zymography and Western blot analysis. The electrophoresis bands were compared on densitometric scans using ImageJ software.

RESULTS

The conditioned media from the isolated human LF cells naturally expressed 72-kD and 92-kD gelatinolytic activities on gelatin zymography. The IL-1β-treated LF cells presented sustained increases in the proenzyme/zymogen forms of MMP−2 and −9 (proMMP-2 and proMMP-9), and activeMMP-9 expression (p = 0.001, 0.022, and 0.036, respectively); the TNFα-treated LF cells showed the most elevated proMMP9 secretion (p = 0.006), as determined by Western blot analyses. ActiveMMP-2 expression was not observed on zymography or the Western blot analysis.

CONCLUSIONS

TNFα and IL-1β promote proMMP-2 and proMMP-9 secretion. IL-1β appears to activate proMMP-9 in human LF cells. Based on these findings, selective MMP-9 blockers or antiinflammatory drugs could be potential treatment options for LF hypertrophy.

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Seung Ah Choi, Sangjoon Chong, Pil Ae Kwak, Youn Joo Moon, Anshika Jangra, Ji Hoon Phi, Ji Yeoun Lee, Sung-Hye Park and Seung-Ki Kim

OBJECTIVE

Endothelial colony-forming cells (ECFCs) isolated from pediatric patients with moyamoya disease (MMD) have demonstrated decreased numbers and defective functioning in in vitro experiments. However, the function of ECFCs has not been evaluated using in vivo animal models. In this study, the authors compared normal and MMD ECFCs using a chronic cerebral hypoperfusion (CCH) rat model.

METHODS

A CCH rat model was made via ligation of the bilateral common carotid arteries (2-vessel occlusion [2-VO]). The rats were divided into three experimental groups: vehicle-treated (n = 8), normal ECFC-treated (n = 8), and MMD ECFC-treated (n = 8). ECFCs were injected into the cisterna magna. A laser Doppler flowmeter was used to evaluate cerebral blood flow, and a radial arm maze test was used to examine cognitive function. Neuropathological examinations of the hippocampus and agranular cortex were performed using hematoxylin and eosin and Luxol fast blue staining in addition to immunofluorescence with CD31, von Willebrand factor, NeuN, myelin basic protein, glial fibrillary acidic protein, and cleaved caspase-3 antibodies.

RESULTS

The normal ECFC-treated group exhibited improvement in the restoration of cerebral perfusion and in behavior compared with the vehicle-treated and MMD ECFC-treated groups at the 12-week follow-up after the 2-VO surgery. The normal ECFC-treated group showed a greater amount of neovasculogenesis and neurogenesis, with less apoptosis, than the other groups.

CONCLUSIONS

These results support the impaired functional recovery of MMD ECFCs compared with normal ECFCs in a CCH rat model. This in vivo study suggests the functional role of ECFCs in the pathogenesis of MMD.

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Hyun-Seung Kang, Youn-Joo Moon, Young-Yim Kim, Woong-Yang Park, Ae Kyung Park, Kyu-Chang Wang, Jeong Eun Kim, Ji Hoon Phi, Ji Yeoun Lee and Seung-Ki Kim

Object

Moyamoya disease (MMD) is a cerebrovascular occlusive disease affecting bilateral internal carotid termini. Smooth-muscle cells are one of the major cell types involved in this disease process. The characteristics of circulating smooth-muscle progenitor cells (SPCs) in MMD are poorly understood. The authors purified SPCs from the peripheral blood of patients with MMD and sought to identify differentially expressed genes (DEGs) in SPCs from these patients.

Methods

The authors cultured and isolated SPCs from the peripheral blood of patients with MMD (n = 25) and healthy control volunteers (n = 22). After confirmation of the cellular phenotype, RNA was extracted from the cells and DEGs were identified using a commercially available gene chip. Real-time quantitative reverse transcription polymerase chain reaction was performed to confirm the putative pathogenetic DEGs.

Results

The SPC-type outgrowth cells in patients with MMD invariably showed a hill-and-valley appearance under microscopic examination, and demonstrated high α–smooth muscle actin, myosin heavy chain, and calponin expression (96.5% ± 2.1%, 42.8% ± 18.6%, and 87.1% ± 8.2%, respectively), and minimal CD31 expression (less than 1%) on fluorescence-activated cell sorter analysis. The SPCs in the MMD group tended to make more irregularly arranged and thickened tubules on the tube formation assay. In the SPCs from patients with MMD, 286 genes (124 upregulated and 162 downregulated) were differentially expressed; they were related to cell adhesion, cell migration, immune response, and vascular development.

Conclusions

With adequate culture conditions, SPCs could be established from the peripheral blood of patients with MMD. These cells showed specific DEGs compared with healthy control volunteers. This study provides a novel experimental cell model for further research of MMD.

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Seung Ah Choi, Sangjoon Chong, Pil Ae Kwak, Youn Joo Moon, Anshika Jangra, Ji Hoon Phi, Ji Yeoun Lee, Sung-Hye Park and Seung-Ki Kim

OBJECTIVE

Endothelial colony-forming cells (ECFCs) isolated from pediatric patients with moyamoya disease (MMD) have demonstrated decreased numbers and defective functioning in in vitro experiments. However, the function of ECFCs has not been evaluated using in vivo animal models. In this study, the authors compared normal and MMD ECFCs using a chronic cerebral hypoperfusion (CCH) rat model.

METHODS

A CCH rat model was made via ligation of the bilateral common carotid arteries (2-vessel occlusion [2-VO]). The rats were divided into three experimental groups: vehicle-treated (n = 8), normal ECFC-treated (n = 8), and MMD ECFC-treated (n = 8). ECFCs were injected into the cisterna magna. A laser Doppler flowmeter was used to evaluate cerebral blood flow, and a radial arm maze test was used to examine cognitive function. Neuropathological examinations of the hippocampus and agranular cortex were performed using hematoxylin and eosin and Luxol fast blue staining in addition to immunofluorescence with CD31, von Willebrand factor, NeuN, myelin basic protein, glial fibrillary acidic protein, and cleaved caspase-3 antibodies.

RESULTS

The normal ECFC-treated group exhibited improvement in the restoration of cerebral perfusion and in behavior compared with the vehicle-treated and MMD ECFC-treated groups at the 12-week follow-up after the 2-VO surgery. The normal ECFC-treated group showed a greater amount of neovasculogenesis and neurogenesis, with less apoptosis, than the other groups.

CONCLUSIONS

These results support the impaired functional recovery of MMD ECFCs compared with normal ECFCs in a CCH rat model. This in vivo study suggests the functional role of ECFCs in the pathogenesis of MMD.

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Hong Joo Moon, Bong-Kyung Shin, Joo Han Kim, Jong-Hyun Kim, Taek-Hyun Kwon, Hung-Seob Chung and Youn-Kwan Park

Intramedullary teratomas, particularly adult cervicothoracic lesions, are extremely rare. Up to now only 6 cases of intramedullary cervical teratomas have been reported in adults, and all of these were histologically mature. The authors present the case of a 35-year-old man with progressive myelopathic symptoms who was admitted through an outpatient clinic and was surgically treated. The characteristics, diagnosis, epidemiology, and treatment of cervical intramedullary teratomas in adults are also reviewed. Postoperative MR imaging showed that the tumor had been near totally removed, and severely adherent tissue remained ventrocranially with tiny focal enhancement on follow-up MR imaging. Pathological examinations revealed immature teratoma without any malignant component. Adjuvant therapy was not performed. Although no change in neurological findings and symptoms was apparent postoperatively, lesion regrowth was demonstrated on MR imaging 4 months after surgery. At 8 months postoperatively, myelopathic symptoms had developed and a huge intramedullary tumor recurred according to MR imaging. This case is the seventh reported instance of intramedullary cervical teratoma in an adult, and the first case report of the immature type with malignant features.

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Ji Hoon Phi, Jung Won Choi, Moon-Woo Seong, Tackeun Kim, Youn Joo Moon, Joongyub Lee, Eun Jung Koh, Seul Ki Ryu, Tae Hee Kang, Jae Seung Bang, Chang Wan Oh, Sung Sup Park, Ji Yeoun Lee, Kyu-Chang Wang and Seung-Ki Kim

OBJECTIVE

In a minority of patients with neurofibromatosis Type 1 (NF-1), cerebral vasculopathy reminiscent of moyamoya disease develops. This phenomenon is called moyamoya syndrome (MMS), but there are no known risk factors for the prediction of MMS in NF-1 patients. Polymorphism of the RNF213 gene has exhibited strong associations with familial and sporadic moyamoya disease and other cerebral vasculopathies. The aim of this study is to find whether the RNF213 c.14576G>A variant is associated with MMS development in the NF-1 population or not.

METHODS

The MMS group included 16 NF-1 patients with documented MMS. The control group consisted of 97 NF-1 patients without MMS. Genomic DNA samples were obtained from the saliva or blood of both groups, and the presence of the RNF213 c.14576G>A variant was assessed by Sanger sequencing.

RESULTS

In the MMS group, 3 patients had the RNF213 c.14576G>A variant (18.7%), whereas no patients with this genetic variation were observed in the control group (0%). There was a meaningful association between the RNF213 c.14576G>A variant and MMS development (p = 0.0024). The crude odds ratio was calculated as 50.57 (95% CI 1.57–1624.41). All 3 patients with MMS and the c.14576G>A variant were diagnosed with MMS at an early age and had bilateral involvement.

CONCLUSIONS

The RNF213 c.14576G>A variant is more common in NF-1 patients who develop MMS than in NF-1 patients without MMS. This variant might be a susceptibility gene for the NF-1–moyamoya connection.

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Jung Won Choi, Sung Min Son, Inhee Mook-Jung, Youn Joo Moon, Ji Yeoun Lee, Kyu-Chang Wang, Hyun-Seung Kang, Ji Hoon Phi, Seung Ah Choi, Sangjoon Chong, Jayoung Byun and Seung-Ki Kim

The authors performed morphological and functional studies of the mitochondria in particular blood cells, i.e., endothelial colony-forming cells (ECFCs), from patients with moyamoya disease. The results indicated that the mitochondria of these ECFCs exhibit morphological and functional abnormalities, which may present new insights into the pathogenesis of moyamoya disease.