Recovery from the damage of cranial radiation modulated by memantine, an NMDA receptor antagonist, combined with hyperbaric oxygen therapy.

BACKGROUND: Radiotherapy is an important treatment option for central nervous system malignancies. However, cranial radiation induces hippocampal dysfunction and white matter injury; this leads to cognitive dysfunction, and results in a reduced quality of life in patients. Excitatory glutamate signaling through N-methyl-d-aspartate receptors (NMDARs) plays a central role both in hippocampal neurogenesis and in the myelination of oligodendrocytes in the cerebrum. METHODS: We provide a method for quantifying neurogenesis in human subjects in live brain during cancer therapy. Neuroimaging using originally created behavioral tasks was employed to examine human hippocampal memory pathway in patients with brain disorders. RESULTS: Treatment with memantine, a non-competitive NMDAR antagonist, reversed impairment in hippocampal pattern separation networks as detected by functional magnetic resonance imaging. Hyperbaric preconditioning of the patients just before radiotherapy with memantine mostly reversed white matter injury as detected by whole brain analysis with Tract-Based Spatial Statics. Neuromodulation combined with the administration of hyperbaric oxygen therapy and memantine during radiotherapy facilitated the restoration of hippocampal function and white matter integrity, and improved higher cognitive function in patients receiving cranial radiation. CONCLUSIONS: The method described herein, for diagnosis of hippocampal dysfunction, and therapeutic intervention can be utilized to restore some of the cognitive decline experienced by patients who have received cranial radiation. The underlying mechanism of restoration is the production of new neurons, which enhances functionality in pattern separation networks in the hippocampi, resulting in an increase in cognitive score, and restoration of microstructural integrity of white matter tracts revealed by Tract-Based Spatial Statics Analysis.

Effect of caffeine contained in a cup of coffee on microvascular function in healthy subjects.

Recent epidemiological studies have demonstrated that coffee drinking is associated with reduced mortality of cardiovascular disease. However, its precise mechanisms remain to be clarified. In this study, we examined whether single ingestion of caffeine contained in a cup of coffee improves microvascular function in healthy subjects. A double-blind, placebo-controlled, crossover study was performed in 27 healthy volunteers. A cup of either caffeinated or decaffeinated coffee was drunk by the subjects, and reactive hyperemia of finger blood flow was assessed by laser Doppler flowmetry. In an interval of more than 2 days, the same experimental protocol was repeated with another coffee in a crossover manner. Caffeinated coffee intake slightly but significantly elevated blood pressure and decreased finger blood flow as compared with decaffeinated coffee intake. There was no significant difference in heart rate between caffeinated and decaffeinated coffee intake. Importantly, caffeinated coffee intake significantly enhanced post-occlusive reactive hyperemia of finger blood flow, an index of microvascular endothelial function, compared with decaffeinated coffee intake. These results provide the first evidence that caffeine contained in a cup of coffee enhances microvascular function in healthy individuals.

Long-term treatment with san'o-shashin-to, a kampo medicine, markedly ameliorates cardiac ischemia-reperfusion injury in ovariectomized rats via the redox-dependent mechanism.

BACKGROUND: Hormone replacement therapy has failed to reduce ischemic cardiovascular events in climacteric women. To explore alternative therapy, we examined whether san'o-shashin-to (TJ-113), a kampo medicine, ameliorates cardiac ischemia-reperfusion (IR) injury in a climacteric rat model. METHODS AND RESULTS: Cardiac function and infarct size after IR were significantly exacerbated in ovariectomized rats as compared with sham-operated rats, whereas long-term treatment with a clinical dosage of TJ-113 for 4 weeks markedly improved these functional and morphological changes. Myocardial inducible nitric oxide synthase (iNOS) expression and peroxynitrite levels were significantly higher in ovariectomized rats compared with sham-operated rats, and long-term TJ-113 treatment significantly reduced these oxidative changes. Furthermore, myocardial manganese superoxide dismutase (Mn-SOD) activity was significantly lower in ovariectomized than in sham-operated rats, and long-term TJ-113 treatment significantly restored antioxidant activity. Importantly, those beneficial actions of TJ-113 were significantly inhibited by the estrogen receptor antagonist, fulvestrant, and the phytoestrogen, emodin, a TJ-113 ingredient, mimicked the actions of TJ-113, suggesting involvement of emodin in the effects of TJ-113. CONCLUSIONS: These results provide the first evidence that long-term treatment with a clinical dosage of TJ-113 markedly ameliorates cardiac IR injury in ovariectomized rats via inhibition of iNOS expression, suppression of peroxynitrite formation, and restoration of Mn-SOD activity. TJ-113 may be a novel therapeutic option in the treatment of ischemic heart disease in climacteric women.

Phase II trial of radiotherapy after hyperbaric oxygenation with multiagent chemotherapy (procarbazine, nimustine, and vincristine) for high-grade gliomas: long-term results.

PURPOSE: To analyze the long-term results of a Phase II trial of radiotherapy given immediately after hyperbaric oxygenation (HBO) with multiagent chemotherapy in adults with high-grade gliomas. METHODS AND MATERIALS: Patients with histologically confirmed high-grade gliomas were administered radiotherapy in daily 2 Gy fractions for 5 consecutive days per week up to a total dose of 60 Gy. Each fraction was administered immediately after HBO, with the time interval from completion of decompression to start of irradiation being less than 15 minutes. Chemotherapy consisting of procarbazine, nimustine, and vincristine and was administered during and after radiotherapy. RESULTS: A total of 57 patients (39 patients with glioblastoma and 18 patients with Grade 3 gliomas) were enrolled from 2000 to 2006, and the median follow-up of 12 surviving patients was 62.0 months (range, 43.2-119.1 months). All 57 patients were able to complete a total radiotherapy dose of 60 Gy immediately after HBO with one course of concurrent chemotherapy. The median overall survival times in all 57 patients, 39 patients with glioblastoma and 18 patients with Grade 3 gliomas, were 20.2 months, 17.2 months, and 113.4 months, respectively. On multivariate analysis, histologic grade alone was a significant prognostic factor for overall survival (p < 0.001). During treatments, no patients had neutropenic fever or intracranial hemorrhage, and no serious nonhematologic or late toxicities were seen in any of the 57 patients. CONCLUSIONS: Radiotherapy delivered immediately after HBO with multiagent chemotherapy was safe, with virtually no late toxicities, and seemed to be effective in patients with high-grade gliomas.