allopurinol and Brain-Diseases

Perinatal hypoxia-ischemia (PHI) is a major cause of morbidity and mortality. A substantial part of PHI-related brain damage occurs upon reperfusion and reoxygenation by the excess production of excitatory amino acids, free (pro)radicals and the release of cytokines, triggering programmed cell death. In this respect, several neuroprotective agents have been investigated in neonatal animal models, providing evidence for their usefulness in PHI. Several agents have been shown to be neuroprotective in neonatal animal hypoxia-ischemia models, but only a few agents have been used in clinical studies on term newborns. Although some general information will be provided with respect to focal hypoxia-ischemia and neuroprotective agents, this paper focuses on the investigated neuroprotective agents for global PHI and reperfusion brain injury in the newborn, categorized by their mode of action. Future experimental and clinical trials with promising neuroprotective agents need to be performed, including long-term follow-up to monitor long-term consequences. Moreover, well-designed combinations of neuroprotective agents with or without other neuroprotective strategies such as brain hypothermia should be given consideration for producing the most promising results in reducing post-hypoxic-ischemic reperfusion injury of the newborn brain.

Topics: Apoptosis; Brain Diseases; Calcium Channel Blockers; Enzyme Inhibitors; Excitatory Amino Acid Antagonists; Free Radical Scavengers; Growth Substances; Humans; Hypoxia-Ischemia, Brain; Infant, Newborn; Inflammation Mediators; Iron Chelating Agents; Neuroprotective Agents; Nitric Oxide; Receptors, N-Methyl-D-Aspartate; Xanthine Oxidase

To investigate the protective effects of allopurinol (ALLO) on white matter damage in premature rats.. An animal model for white matter damage was established by bilateral carotid artery occulation (BCAO). Eighty-four newborn SD rats (1 day old) were used in this study and were divided randomly into three groups [sham surgery (Sham); BCAO group (BCAO); allopurinol-treated group (ALLO)]. Pathological changes were studied 7 days and 14 days after BCAO, respectively. Myelin basic protein (MBP) was detected by immunohistochemistry 7 days and 14 days after BCAO, respectively. MBP-mRNA expression was determined 7 days and 14 days after BCAO respectively by reverse transcription-polymerase chain reaction (RT-PCR) with fluorescent quantitative method.. In BCAO group, mild or severe rarefaction was found in 10 cases in the corpus callosum area, especially at the cingulum. Pathological changes of white matter were found in 4 cases in internal capsule. Subcortex white matter rarefaction was found in 8 cases. The extent of white matter rarefaction in ALLO group was reduced significantly. Enlargement of bilateral ventricles was found in 6 of 8 cases in BCAO group. The average ventricle size in ALLO group (2.44 +/- 0.71)% was reduced significantly as compared with that in BCAO group (3.27 +/- 0.73)% (P < 0.05). Strong MBP positive staining was found in sub-cortex, corpus callosum, hippocampus gyrus, and internal capsule of P14 sham surgery group. In BCAO group the MBP staining extent was reduced. The extent of MBP staining of ALLO group was between the other two groups. The optical density (OD) of MBP positive staining in BCAO group (6.60 +/- 0.68) was found higher than that in sham surgery group (9.40 +/- 0.53), the difference was statistically significant (P < 0.05). Compared with BCAO group, OD value in ALLO group (7.10 +/- 0.18) increased significantly (P < 0.05). RT-PCR data showed that MBP-mRNA copies (log10) in P7 and P14 rats of both BCAO and ALLO groups were lower than that in sham surgery group (P < 0.01); However, MBP-mRNA copies in ALLO group were higher than that in BCAO group (P < 0.05).. BCAO could be used in newborn rats (1 day old) to establish a premature white matter damage (WMD) animal model. Allopurinol may have a potential protective effect on premature SD rat with ischemic WMD.

Topics: Allopurinol; Animals; Animals, Newborn; Brain; Brain Diseases; Disease Models, Animal; Immunohistochemistry; Myelin Basic Protein; Random Allocation; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

Topics: Allopurinol; Brain Diseases; Child; Diagnosis, Differential; Female; Fever; Heat Exhaustion; Humans; Hungary; Male; Shock, Hemorrhagic; Syndrome; Terminology as Topic

We studied the cerebral effects of oxygen-derived free radicals generated from the xanthine oxidase/hypoxanthine/ADP-Fe3+ system. Xanthine oxidase/hypoxanthine/ADP-Fe3+ solution (0.1 ml) was infused into caudate putamen, and brain was frozen rapidly in situ. Brain water and sodium content increased concomitant with decreased potassium content at 24 hours and 48 hours after the infusion. The degree of brain edema and injury depended on the dose of xanthine oxidase. Spongy neuropil and neuronal cytoplasmic vacuoles were seen at 2 hours, with an infiltration by polymorphonuclear leukocytes at 24 hours, followed by lipid-laden macrophages and reactive astrocytes. Leakage of fluorescent dye into neuropil was seen at 2 hours, but not later. These data suggest that oxygen-derived free radicals damage endothelial cells of the blood-brain barrier; the brain injury is characterized by edema and by structural damage of neurons and glia.

Topics: Adenosine Diphosphate; Animals; Blood-Brain Barrier; Brain; Brain Diseases; Brain Edema; Capillary Permeability; Free Radicals; Hypoxanthine; Hypoxanthines; Iron; Male; Oxygen; Rats; Rats, Inbred Strains; Xanthine Oxidase

In an attempt to decrease the activation of 5-FU by normal cells relative to cancer cells, 20 patients with metastatic cancer were given 72 courses of 5-FU and allopurinol (HPP) in a phase I trial. 5-FU was given daily by iv bolus injection for 5 consecutive days every 4 weeks: HPP, 300 mg orally every 8 hours for 6 consecutive days, was started 24 hours before the first injection of 5-FU. HPP appeared to modulate 5-FU toxicity by allowing higher doses (18-21 mg/kg daily for 5 days) to be given. Unexpectedly, neurotoxicity was the dose-limiting toxicity; it was slowly reversible and manifested primarily as encephalopathy, with some patients having cerebellar signs. Gastrointestinal and hematologic toxic effects were mild and infrequent. Because of the high incidence of neurotoxicity and low response rate, this program does not appear to offer any advantages over conventional dose schedules of 5-FU alone.

Topics: Adenocarcinoma; Aged; Allopurinol; Brain Diseases; Drug Administration Schedule; Drug Evaluation; Drug Therapy, Combination; Fluorouracil; Gastrointestinal Diseases; Humans; Male; Middle Aged; Neutropenia

Topics: Adenosine Triphosphate; Allopurinol; Anemia; Brain Diseases; Carbon Isotopes; Child, Preschool; Erythrocytes; Fibroblasts; Humans; Infant; Intellectual Disability; Kidney Diseases; Male; Metabolism, Inborn Errors; Purines; Self Mutilation; Transferases; Uric Acid