Astaxanthin offers neuroprotection and reduces neuroinflammation in experimental subarachnoid hemorrhage.

BACKGROUND: Neuroinflammation has been proven to play a crucial role in early brain injury pathogenesis and represents a target for treatment of subarachnoid hemorrhage (SAH). Astaxanthin (ATX), a dietary carotenoid, has been shown to have powerful anti-inflammation property in various models of tissue injury. However, the potential effects of ATX on neuroinflammation in SAH remain uninvestigated. The goal of this study was to investigate the protective effects of ATX on neuroinflammation in a rat prechiasmatic cistern SAH model. METHODS: Rats were randomly distributed into multiple groups undergoing the sham surgery or SAH procedures, and ATX (25 mg/kg or 75 mg/kg) or equal volume of vehicle was given by oral gavage at 30 min after SAH. All rats were sacrificed at 24 h after SAH. Neurologic scores, brain water content, blood-brain barrier permeability, and neuronal cell death were examined. Brain inflammation was evaluated by means of expression changes in myeloperoxidase, cytokines (interleukin-1ß, tumor necrosis factor-α), adhesion molecules (intercellular adhesion molecule-1), and nuclear factor kappa B DNA-binding activity. RESULTS: Our data indicated that post-SAH treatment with high dose of ATX could significantly downregulate the increased nuclear factor kappa B activity and the expression of inflammatory cytokines and intercellular adhesion molecule-1 in both messenger RNA transcription and protein synthesis. Moreover, these beneficial effects lead to the amelioration of the secondary brain injury cascades including cerebral edema, blood-brain barrier disruption, neurological dysfunction, and neuronal degeneration. CONCLUSIONS: These results indicate that ATX treatment is neuroprotective against SAH, possibly through suppression of cerebral inflammation.

Differential numbers of foci of lymphocytes within the brains of Lewis rats exposed to weak complex nocturnal magnetic fields during development of experimental allergic encephalomyelitis.

To discern if specific structures of the rat brain contained more foci of lymphocytes following induction of experimental allergic encephalomyelitis and exposures to weak, amplitude-modulated magnetic fields for 6 min once per hour during the scotophase, the residuals between the observed and predicted values for the numbers of foci for 320 structures were obtained. Compared to the brains of sham-field exposed rats, the brains of rats exposed to 7-Hz 50 nT (0.5 mG) amplitude-modulated fields showed more foci within hippocampal structures and the dorsal central grey of the midbrain while those exposed to 7-Hz 500 nT (5 mG) fields showed greater densities within the hypothalamus and optic chiasm. The brains of rats exposed to either the 50 nT or 500 nT amplitude-modulated 40-Hz fields displayed greater densities of foci within the midbrain structures related to rapid eye movement. Most of the enhancements of infiltrations within the magnetic field-exposed rats occurred in structures within periventricular or periaqueductal regions and were both frequency- and intensity-dependent. The specificity and complexity of the configurations of the residuals of the numbers of infiltrated foci following exposures to the different fields suggest that the brain itself may be a "sensory organ" for the detection of these stimuli.

A method for the generation of monoclonal antibodies against rare cell-surface molecules.

Monoclonal antibodies provide a powerful tool for the identification and analysis of novel cell-surface molecules. We present here a method for antigen preparation and an immunization protocol that facilitates generation of mAb reactive with cell-surface molecules of low abundance and/or low antigenicity. The procedure involves isolation and extensive fractionation of cell-surface and detergent-soluble extracellular-matrix molecules prior to immunization. Cell-surface proteins on intact tissue are biotin-labeled using a reagent that does not penetrate cells. Avidin affinity chromatography is then used to purify these biotinylated molecules. Size-exclusion HPLC is used to separate these surface molecules on the basis of apparent molecular mass. Finally, immunization with antigen coupled to keyhole-limpet hemocyanin is combined with long-term booster immunizations to generate a hyperimmune response resulting in high-affinity IgG. A test application of this approach was aimed at the generation of mAb against cell-surface molecules of approximately 135 kDa in the developing chicken retinotectal system. Immunochemical analyses using antibodies produced by this approach which showed restricted patterns of tissue staining reveal that mAb were generated against all previously identified immunoglobulin superfamily molecules of this size in this system. Furthermore, we produced many additional antibodies that labeled retinotectal tissue in novel staining patterns. In the two cases analyzed in detail, these new patterns reflect the distributions of previously uncharacterized members of the immunoglobulin superfamily. The success of this initial study suggests that this method may represent a broadly applicable approach towards the preparation of extensive libraries of antibodies against cell-surface molecules expressed on cells from numerous sources.

The presence of serotonin-immunoreactive nerve fibers in the optic nerve of the mouse.

Serotonin immunoreactivity was investigated in the optic nerve of the mouse by use of mono- and polyclonal antisera and the indirect peroxidase-antiperoxidase technique. A number of serotonin-immunoreactive nerve fibers with beaded appearance were demonstrated mainly orientated along its longitudinal axis. Since several studies have failed to demonstrate perikarya immunoreactive to serotonin in the mammalian retina, the presence of serotoninergic fibers in the optic nerve further supports a retinopetal innervation.