Naokado Ikeda

Bone Marrow Stromal Cells That Enhanced Fibroblast Growth Factor-2 Secretion by Herpes Simplex Virus Vector Improve Neurological Outcome After Transient Focal Cerebral Ischemia in Rats

Background and Purpose— Fibroblast growth factor-2 (FGF-2) administration and bone marrow stromal cell (MSC) transplantation could improve neurological deficits after occlusive cerebrovascular disease. In the present study, we examined the effects of neurological improvement after transient middle cerebral artery occlusion (MCAO) in rats by a novel therapeutic strategy with FGF-2 gene–transferred MSCs by the herpes simplex virus type 1 (HSV-1) vector. Methods— Adult Wistar rats were anesthetized. Nonmodified MSCs, FGF-2–modified MSCs with HSV-1 1764/-4/pR19/ssIL2-FGF-2, or PBS was administered intracerebrally 24 hours after transient right MCAO. All animals underwent behavioral tests for 21 days, and the infarction volume with 2-3-5-triphenylterazolium was detected 3 days and 14 days after the MCAO. Three days and 7 days after the MCAO, the FGF-2 production in the ipsilateral hemisphere of the MCAO was measured with ELISA. Seven and 14 days after the MCAO, immunohistochemical staining for FGF-2 was applied. Results— The stroke animals receiving FGF-2–modified MSCs demonstrated significant functional recovery compared with the other groups. Fourteen days after the MCAO, there was a significant reduction in infarction volume only in FGF-2–modified MSC-treated group. FGF-2 production in the FGF-2–modified MSC-treated brain was significantly higher compared with the other groups at 3 and 7 days after MCAO. Administrated FGF-2–modified MSCs strongly expressed the FGF-2 protein, which was proven by ELISA. Conclusions— Our data suggest that the FGF-2 gene–modified MSCs with the HSV-1 vector can contribute to remarkable functional recovery after stroke compared with MSCs transplantation alone.

VASCULAR ENDOTHELIAL GROWTH FACTOR GENE-TRANSFERRED BONE MARROW STROMAL CELLS ENGINEERED WITH A HERPES SIMPLEX VIRUS TYPE 1 VECTOR CAN IMPROVE NEUROLOGICAL DEFICITS AND REDUCE INFARCTION VOLUME IN RAT BRAIN ISCHEMIA

OBJECTIVESeveral reports recently suggested that vascular endothelial growth factor (VEGF) may have a therapeutic benefit against experimental cerebral infarction animal models. In addition, bone marrow stromal cells (BMSCs) are known to have therapeutic potency in improving neurological deficits after occlusive cerebrovascular diseases. In the present study, we evaluated the hypothesis that intracerebral transplantation of VEGF gene-transferred BMSCs could provide a greater therapeutic effect than intracerebral transplantation of native (non-gene-transformed) BMSCs by using a transient middle cerebral artery occlusion (MCAO) rat model. METHODSAdult Wistar rats (Japan SLC, Inc., Hamamatsu, Japan) were anesthetized. VEGF gene-transferred BMSCs engineered with a replication-deficient herpes simplex virus type 1 1764/4-/pR19-hVEGF165 vector, native BMSCs, or phosphate-buffered saline were administered intracerebrally 24 hours after transient MCAO. All animals underwent behavioral testing for 28 days, and the infarction volume was determined 14 days after MCAO. The brain water contents in the ipsilateral and contralateral hemispheres of the MCAO were measured 2 and 7 days after the MCAO. Fourteen days after MCAO, immunohistochemical staining for VEGF was performed. RESULTSThe group receiving VEGF-modified BMSCs demonstrated significant functional recovery compared with those receiving native BMSCs. Fourteen days after the MCAO, there was a significantly lower infarct volume without aggravating cerebral edema in the group treated with VEGF gene-modified BMSCs compared with the control groups. The transplanted VEGF gene-modified BMSCs strongly expressed VEGF protein for at least 14 days. CONCLUSIONOur data suggest that the intracerebral transplantation of VEGF gene-transferred BMSCs may provide a more potent autologous cell transplantation therapy for stroke than the transplantation of native BMSCs alone.

Enhanced expression of coproporphyrinogen oxidase in malignant brain tumors: CPOX expression and 5-ALA–induced fluorescence

In photodynamic diagnosis, 5-aminolevulinic acid (5-ALA) is widely used for the fluorescence-guided resection of malignant brain tumors, where 5-ALA is converted to protoporphyrin IX, which exhibits strong fluorescence. Little is known, however, about the detailed molecular mechanisms underlying 5-ALA-induced fluorescence. To resolve this issue, we analyzed transcriptome profiles for the genes encoding enzymes, transporters, and a transcription factor involved in the porphyrin-biosynthesis pathway. By quantitative real-time (qRT)-PCR, we measured the mRNA levels of those genes in a total of 20 tumor samples that had been surgically resected from brain tumor patients at the Department of Neurosurgery of Osaka Medical College from 2008 to 2009. We selected 10 tumor samples with no 5-ALA-induced fluorescence, among which 2 were glioblastomas and 8 were metastatic brain tumors. Another 10 tumor samples were selected with strong fluorescence, among which 7 were glioblastomas and 3 were metastatic brain tumors. The qRT-PCR analysis study of these latter 10 samples revealed predominantly high levels of the mRNA of the coproporphyrinogen oxidase (CPOX) gene. The high mRNA level of CPOX expression was significantly well correlated with the phenotype of strong 5-ALA-induced fluorescence (P = .0003). These findings were further confirmed by immunohistochemical studies with a CPOX-specific antibody. It is concluded that induction of CPOX gene expression is one of the key molecular mechanisms underlying the 5-ALA-induced fluorescence of malignant brain tumors. The induction mechanism for the CPOX gene in brain tumors remains to be elucidated.

Computed Tomography Imaging of Transferrin Targeting Liposomes Encapsulating Both Boron and Iodine Contrast Agents by Convection-Enhanced Delivery to F98 Rat Glioma for Boron Neutron Capture Therapy

BACKGROUND:To achieve potent tumor-selective antitumor efficacy by boron neutron capture therapy (BNCT), it is important to have a significant differential uptake of 10B between tumor cells and normal cells. This should enable BNCT to reduce damage to normal tissues compared with other radiation therapies. OBJECTIVE:To augment the therapeutic efficacy of BNCT, we used transferrin-conjugated polyethylene glycol (PEG) (TF-PEG) liposome encapsulating sodium borocaptate and Iomeprol, an iodine contrast agent, with intratumoral convection-enhanced delivery (CED) in a rat glioma tumor model. METHODS:The in vitro 10B concentration of F98 rat glioma cells was determined by inductively coupled plasma atomic emission spectrometry after incubation with either TF-PEG or PEG liposomes. For in vivo biodistribution studies, 10B concentrations within blood, normal brain tissue, and intracerebrally transplanted F98 cells were measured with inductively coupled plasma-atomic emission spectrometry after CED of the compounds, and computed tomography was performed at selected time intervals. RESULTS:10B concentrations of F98 cultured glioma cells in vitro 6 hours after exposure to PEG and TF-PEG liposome were 16.1 and 51.9 ng10B/106 cells, respectively. 10B concentrations in F98 glioma tissue 24 hours after CED were 22.5 and 82.2 μg/g, by PEG and TF-PEG liposome, respectively, with lower 10B concentrations in blood and normal brain. Iomeprol provided vivid and stable enhanced computed tomography imaging of the transplanted tumor even 72 hours after CED by TF-PEG liposome. Conversely, tissue enhancement had already washed out at 24 hours after CED of the PEG liposomes. CONCLUSION:The combination of TF-PEG liposome encapsulating sodium borocaptate and Iomeprol and intratumoral CED enables not only a precise and potent targeting of boron delivery to the tumor tissue, but also the ability to follow the trace of boron delivery administered intratumorally by real-time computed tomography.

Transporter-Mediated Drug Interaction Strategy for 5-Aminolevulinic Acid (ALA)-Based Photodynamic Diagnosis of Malignant Brain Tumor: Molecular Design of ABCG2 Inhibitors

Photodynamic diagnosis (PDD) is a practical tool currently used in surgical operation of aggressive brain tumors, such as glioblastoma. PDD is achieved by a photon-induced physicochemical reaction which is induced by excitation of protoporphyrin IX (PpIX) exposed to light. Fluorescence-guided gross-total resection has recently been developed in PDD, where 5-aminolevulinic acid (ALA) or its ester is administered as the precursor of PpIX. ALA induces the accumulation of PpIX, a natural photo-sensitizer, in cancer cells. Recent studies provide evidence that adenosine triphosphate (ATP)-binding cassette (ABC) transporter ABCG2 plays a pivotal role in regulating the cellular accumulation of porphyrins in cancer cells and thereby affects the efficacy of PDD. Protein kinase inhibitors are suggested to potentially enhance the PDD efficacy by blocking ABCG2-mediated porphyrin efflux from cancer cells. It is of great interest to develop potent ABCG2-inhibitors that can be applied to PDD for brain tumor therapy. This review article addresses a pivotal role of human ABC transporter ABCG2 in PDD as well as a new approach of quantitative structure-activity relationship (QSAR) analysis to design potent ABCG2-inhibitors.

Reversible Hypopituitarism with Pituitary Tuberculoma

A 50-year-old woman presented with a headache and nausea. A sellar and suprasellar mass was detected on MRI; the tumor was heterogeneously enhanced with gadolinium, and the pituitary stalk was slightly thickened. Laboratory tests revealed severe growth hormone, luteinizing hormone, follicle-stimulating hormone and thyroid-stimulating hormone deficiencies. A pathological examination of the tumor showed scattered granulomas with central necrosis and Langhans giant cells. Tuberculin skin and QuantiFERON TB-Gold tests (QFT-2G) were positive. Accordingly, we diagnosed the patient with pituitary tuberculoma presenting with pituitary dysfunction. Following treatment with antituberculous drugs, the pituitary hormone function normalized and the pituitary tuberculoma disappeared.

Posterior atlantoaxial fusion as treatment option for extracranial vertebral artery dissecting aneurysm: a case report and literature review

Symptomatic extracranial vertebral artery (VA) dissection may need surgery. We describe such a case successfully treated with atlantoaxial fusion based on its rare dynamic angiographic findings. A 27-year-old woman suffered from repeated brainstem and cerebellar infarctions from a left extracranial VA dissecting aneurysm. Dynamic angiography showed the dissecting aneurysm of the V3 segment in the neutral head position, and deflation of the aneurysm during rightward head rotation. She underwent posterior atlantoaxial fusion, and the lesion was repaired with no subsequent ischemia. Posterior atlantoaxial fusion can be an option for some extracranial VA dissections with preserving its anterograde blood flow.

Assessment of safety of 5-aminolevulinic acid–mediated photodynamic therapy in rat brain

BACKGROUND Oral 5-aminolevulinic acid (ALA) induces biosynthesis/accumulation of the natural photo-sensitizer protoporphyrin IX (PpIX) in cancer cells. ALA is used widely in photodynamic diagnosis (PDD) and therapy (PDT) during malignant glioma surgery, but few studies have examined the effects of photodynamics plus ALA on normal brain tissue in vivo. We investigated the effects of ALA-mediated PDD and PDT on normal brain tissue. METHODS We established a rat model in which the brain surface was irradiated through the skull by light-emitting diode (635 nm) after ALA administration. Using this model, we investigated the effects of various amounts of light irradiation with various ALA doses on brain tissue. RESULTS Neurological symptoms developed with administration of ALA at 240 or 120 mg/kg accompanied by irradiation at 100 or 400 J/cm2, respectively. Dye leakage occurred due to disruption of the blood-brain barrier (BBB) at 90 mg/kg and 100 J/cm2, respectively. Thickness of the cortex increased significantly at 240 mg/kg and 400 J/cm2, respectively. The number of neurons appeared to decrease at 200 mg/kg plus 400 J/cm2, respectively, and there was an increase in the number of cells that were positive for terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling (TUNEL) staining. CONCLUSIONS ALA-mediated PDT is safe at doses of 90 mg/kg or less followed by light irradiation of 100 J/cm2 in rat brains. At doses above this threshold, ALA-PDT led to irreversible BBB and brain damage in rats.

Fluoroscopic-Guided Paramedian Approach for Lumbar Catheter Placement in Cerebrospinal Fluid Shunting: Assessment of Safety and Accuracy

Abstract BACKGROUND Spinal catheter insertion in lumboperitoneal (LP) shunt surgery for idiopathic normal pressure hydrocephalus (iNPH) is frequently associated with technical difficulties especially in patients with obesity and elderly patients with vertebral deformities. OBJECTIVE To elucidate the accuracy and safety of image-guided spinal catheter placement using a paramedian approach (PMA). METHODS We retrospectively analyzed 39 consecutive iNPH patients treated by LP shunting with spinal catheter insertion via the PMA. The success rate of catheter placement and the number of changes in puncture location were evaluated. Accuracy of catheter insertion was assessed by measuring both vertical and horizontal deviations in the point of catheter dural penetration from the center of the interlaminar space. RESULTS The success rate of catheter placement was 100% (39/39). The difficulty rate for catheter insertion, measured by the number of changes in puncture location, was 2.6% (1/39). No bloody punctures or surgical infections were observed. Accuracy of catheter insertion, measured as the degree of deviation, was 0.5 ± 1.9 mm horizontally and 0.0 ± 2.4 mm vertically. The rates of minor complications, including caudal catheter insertion, transient low-pressure headache, and root pain, were 5.1% (2/39), 10.4% (4/39), and 0% (0/43), respectively. Subdural hematoma requiring surgical intervention occurred in 1 case (2.6%). During the mean follow-up period of 36 mo, spinal catheter rupture at the level of the spinous processes was not observed. CONCLUSION Fluoroscopic-guided spinal catheter placement via the PMA was safe, accurate, and reliable, even for use in geriatric and obese patients.

Limit of intraoperative near-infrared spectroscopy monitoring during endovascular thrombectomy in acute ischemic stroke

Endovascular thrombectomy is recommended for a persistent ischemic penumbra if recanalization cannot be achieved by the intravenous (IV) administration of recombinant tissue-plasminogen activator (rt-PA) alone. Although endovascular thrombectomy is a powerful treatment for major cerebral artery occlusion, the monitoring of recanalization and reperfusion during acute ischemic stroke presents a therapeutic challenge, and a previous study reported the usefulness of near-infrared spectroscopy (NIRS) for intraoperative monitoring during emergency endovascular thrombectomy for acute large ischemic stroke. Here we present our experience with a relevant case series. We applied NIRS monitoring during endovascular thrombectomy in two patients with large ischemic stroke following carotid artery occlusion and one patient with a non-large ischemic stroke caused by a distal middle cerebral artery (MCA) occlusion. In the patients with large ischemic stroke, complete recanalization of the internal carotid artery was achieved, and NIRS revealed a very good regional oxygen saturation (rSO2) response. By contrast, in the patient with non-large ischemic stroke, the rSO2 did not change, despite complete recanalization of the distal MCA. Our findings suggest the limited usefulness of intraoperative NIRS monitoring during emergency endovascular thrombectomy for non-large acute ischemic stroke caused by a distal MCA occlusion. However, intraoperative NIRS monitoring could be used practically to detect recanalization of the major artery during thrombectomy and early IV rt-PA administration in cases involving major artery occlusion.